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The work is aimed at the occurrence of secondary malignities (duplicities) after the treatment for primary carcinoma of testes. The target of the work was to determine the number of secondary tumours, their effects on total survival and furthermore to compare relative risks of the origination of secondary tumours depending on particular treatment modalities.
The group comprises 313 patients with carcinoma of testes, who were subjected to surgery in 1968 - 1998 with subsequent treatment by irradiation, chemotherapy or with the use of both modalities. Statistical methods included the assessment of relative risks (RR), Fisher test or c2-test, log-rank test and survival analyses according to Kaplan-Meier.
Total of 22 secondary tumours, i.e. 7%, were found. The relative risk of the origination of duplicity in this group was low, 1.044. The median time up to the origination of secondary tumour was of 143 months. The median symptomless survival and total survival decreased from 271 months to 187.3 and 199.8 months, respectively.
Two hundred and thirteen patients experienced radiotherapy, which was associated with enhanced risk of the origination of secondary tumours (RR = 8.38). In contrast, in 100 patients subjected to chemotherapy, there was a low risk (RR = 0.38).
Patients with carcinoma of testes have mostly a long-term prognosis and thus, it is necessary to take into account secondary malignities and to include them into making decisions about the treatment and further dispensarization.

In the course of recent years, the occurrence of a new subtype of the influenza A virus (H5N1), so called bird influenza, resulted in fear. First reports on the virus came from Italy, from the beginning of the last century. The virus was first isolated in South Africa in 1961. It first infected humans in Hong Kong in 1997. From the middle of 2003 it caused the largest and most severe infections of the poultry, and in December 2003, infections in people, who were in contact with sick birds, were recorded. Since then, the disease was demonstrated by laboratory diagnosis in over 100 patients in four Asian countries (Indonesia, Cambodia, Thailand and Vietnam) and more than half the patients died. Most cases occurred in children and young adults, who were healthy before this infection. Birds are hosts of this virus. The infection propagates most rapidly in domestic birds. The disease also occurs in free-living, migrating birds. The virus cannot be easily transferred to humans. The transfer from man to man is also not easy. If H5N1 were mutated into a form as infectious as human influenza, there would be a danger of pandemic. The propagation of the bird influenza leads countries throughout the world to the development of plans for suppressing possible pandemic. The disease development can be positively affected by two drugs from the group of neuraminidase inhibitors. The first drug is oseltamivir (Tamiflu), which is available on our market, the second drug being zanamivir (Relenza), which is not available there. Particularly vaccination is of prior importance in the influenza prevention.

Nursing, similarly as many other areas of the human knowledge and activity, led in its historical genesis to a scientific form, which is mainly characterized by the subject of investigation, scientific method, language, method of acquiring data and their implementation. Thus, nursing belongs to scientific disciplines, which is considered as a real and humanitarian science (from the standpoint of its subject) and applied science (from the standpoint of its target). The subject of the examination is man as whole, which means that all the partial results of the research are in their understanding and interpretation considered as whole, i. e. holistically. The whole method is also adjusted for this purpose, which should be appropriate just for an individual as a bio-psychosocial human being with his/her unique mental dimension. Development of the research and scientific basis of nursing became an unavoidable assumption for providing the nursing care.
Nursing is not only an extraordinarily demanding occupation. It is also a stimulating and pleasurable role, in which mastering of special works is combined with willingness to help the people and to bring them benefits from this work. Interconnection between special knowledge and practical skill with deep altruism manifested by kind taking care of man is a typical feature of contemporary nursing. In the present hectic times, characterized by modern sophisticated techniques, nursing extends and enhances quality of the nursing process. Nursing is combined with medicine; it is a science but also simultaneously an art. Good nurse is a God gift; she fulfils multiple functions and roles.
Scientific work is a motor of the activity of both medicine and nursing. The final criterion of the truth is practice. Science drives the practice forward and practice grants an invention for the scientific work. The theory and practice enrich each other. It is necessary to emphasize that theory is blind without practice and practice is deaf without theory. Ethics is conditio sine qua non in the nursing activity and thus also in the scientific work.

One of the aims solved by the authors of the grant task called VEGA No. 1/2484/05: Problems of death and dying of man. Theoretical points of departure and practical consequences, analysis of problems of hope. In the effort to interconnect theoretical points of departure with the praxis, the authors have decided to address validation of nursing diagnosis called Hopelessness. Categorization of nursing diagnoses together with their diagnostic characteristics, their clinical applicability and reflexion of socio-cultural differences are basic preconditions of applicability of the terminology in international context. The use of the NANDA taxonomy provokes discussions among teachers, nurses, but also students. Most frequently, the critics concerns just the terminology of diagnoses and broad demarcation of their diagnostic characteristics, which are problematic from the point of view of their objectification.
The authors of the study have used the modified Fehring Diagnostic Content Validity Model. They designed a measuring tool to assess the significance of diagnostic characteristics of the Hopelessness diagnosis. The measuring tool contained 37 diagnostic characteristics. On the base of answers of experts (teachers and nurses) who assessed the diagnostic characteristics from NANDA International and the characteristics created from Nowotny Hope Scale, the authors of the study determined subsequently the defining diagnostic characteristics of Hopelessness, which they present in the text.
In the scope of the study, they ascertained also the rate of dependence among individual defining characteristics through calculation of a simple linear correlation (Pearson correlation coefficient) and determined also the level of critical statistic significance of this correlation.
The conclusions following from the study, as well as results of other authors (Fadden, Fehring, Sato, Wake) advert to current need of unification of results of multi-ethnical validation studies, including their subsequent clinical validation.

The article concerns certain theoretical concepts of the stigma and psycho-social nature of the stigmatization process, and emotional impact of the stigma in its relationship to the identification, anticipation, understanding and solving this problem is shown. The article offers a brief review of the development of the concept of stigma. This concept is neither static nor precisely delimited, but the contents of the concept as well as its delimitation are affected by social changes. The author elucidates the importance of the work by E. Goffman - Stigma: Notes on the management of spoiled identity, where the stigma definition may be understood as a starting point for further sociological research work. The importance of the work by E. Jones et al. - Social stigma, the psychology of market relationships, for the investigation of the effect of the stigmatization on the mental condition of the person involved is explained. The emotional impact of these induced feelings is considered as a consequence of social expectations. The result is a development of the mental strategy aimed at social aspects of the stigma. These aspects are categorized into six dimensions: possibility of concealment, course, destructivity, esthetical features, origin and risk. In the conclusion of the article, the stigma is considered in its relationship to the concept of the patient role. The importance of the role of health personnel in the stigmatization process is mentioned, and there is a brief treatise on the process of the "medicinalization" in the contemporary society. The reaction on this condition is an increase of the confidence of patients in individual activities, self-help, accepting responsibility for their health condition, but also addressing alternative services. This results in attempts for compilation of codes of "rights of patients".

The present contribution deals with the problem of the food ingestion. Mental anorexia and bulimia present in their manifestations limit points of the eating behaviour, from the life threatening intake of the food to excess eating with subsequent cleansing or starvation. Due to unsuitable eating habits and use of dangerous methods of controlling the body mass and physical discontent, also generalized to other areas of the personal life, obese people suffer from the same mental and somatic problems as those with bulimia and anorexia. However, the clinical pattern and social problems in these two categories of disorders of the food ingestion are considerably different. There are also different patterns in the constitution, anamnesis, but also in the personality structure and thus, the health consequences are also quite different. The reason for the growing number of disorders of the food ingestion is considered by most authors as the varying culture, which uncritically celebrates the slenderness and one-sided self-control. The trendy industry, films, journals and TV propagate opinions that the skinny slenderness is the most important aspect of the physical attractiveness. Roots of every fear and thus also of the fear of the fatness are present in the everyday life and in the world surrounding people. There is so-called multi-factorial concept, which is becoming a generally accepted standard for the description, interpretation and therapy of disorders of the food ingestion in recent years. The problem of the control of the body mass, obesity and disorders of the food ingestion has many levels pervading and conditioning each other. The multi-factorial concept includes social-cultural and family effects, chronic problems and adverse events and, last but not least, also biological factors.

The main target of the present research was to establish the situation in the experience, use and spectrum, including intensity and availability, concerning illegal drugs used by students at the University of South Bohemia, also with taking into account associations with the load in the course of the study. Partial target 1 was aimed at questions whether university students come with their own former experience with illegal drugs. Partial target 2 of the research was to ascertain, whether users of drugs come from sites of residence with enhanced concentration of inhabitants. The total number of respondents was obtained based on random choice from the pool of students residing at student hostels of the University of South Bohemia. The random choice was provided by addressing students in student hostels, in every other room, at a randomly chosen hostel and randomly chosen floor. Data were always accumulated on one day to prevent possible duplicity of respondents. The research was implemented by a quantitative form with the use of a technique of questionnaires on 208 respondents. The questionnaire comprised total of 26 questions. The respondents answered the questions anonymously, with differentiation depending on the age, gender, use of drug, concentration of inhabitants and size of the population at the site of residence and their own relationship to drugs, including their availability, motivation factors and determination of the situation of using drugs before and after their admission to the University. The respondents also had a possibility to present one or more answers, provided that the possibility of multiple answers was also specified with each particular question.

Regional planning in the Czech Republic solves continuously and complexly the function use of the region, sets the principles of its organization and coordinates building and other activities influencing the territory development from material and time point of view. It creates conditions to ensure permanent harmony of all natural, civilization and cultural values in the region, particularly with regard to care for environment and protection of its principal components like soil, water and atmosphere.
In current legislation of the Czech Republic, the Ministry for local development, Ministry of defense, the region or the community are bound to perform regional planning and technical documentation, regional plans of large regional complexes or communities.
The author of the article addresses the use of regional plan and geographical information system of community in crisis management (planning). He focuses on current legislation in regional planning and on legislation valid from January 1st, 2007, concentrated particularly on the community and on proposals for solution of requirements of civil protection of community regional plan, delimitation of lands of buildings beneficial to the public and proposals for solution of requirements of civil protection in regulation plan of the community. It is the so called clause of civil protection that has its particularities and is focused on protection of population. Last but not least, the article points out the use of the regional plan of the community in geographic information system of the Písek town and introduction of new data over the scope of current legislation.

By smoking tobacco we mean inhalation of the smoke from burning dried tobacco leaves. This practice was common in many original inhabitants of America and it was brought into the rest of the world by sailors, who participated in first voyages of Europeans to the American continent. The most common form of smoking tobacco is smoking cigarettes. The tobacco smoke contains nicotine, which is a substance temporarily stimulating the alertness and memory, but it simultaneously induces a strong physical and mental dependence. Medical research demonstrated that smoking considerably participates in many health problems, particularly lung cancer, emphysema and cardiovascular diseases. Thus, a number of countries try to restrict sales of tobacco products and by restricting their advertisements and by prohibiting smoking at public places, they try to diminish effects of the smoke on non-smokers. Nicotine is a primary addictive substance in smoking tobacco. In this short review, we consider the dependence on nicotine and genetics of smokers with respect to cytochrome P450 (CYP2A6). In humans, nicotine is inactivated by its biotransformation to cotinine and CYP2A6 makes about 90% of this conversion. However, not all the people believe that genetic variations in CYP2A6 may play their important role in smoking. We summarize certain more recent findings about effects of the CYP2A6 genetic polymorphism, pharmacokinetics of nicotine, behaviour of smokers and concepts concerning possible ways of affecting different effects in the course of particular smoking stages by genes. Application of these findings to new and original methods of stopping smoking is discussed. Persons with slow metabolic conversion of nicotine and those with prevalent symptoms of depression are at enhanced risk of the dependence on nicotine.

Alcohol is the most extensively used drug and alcoholism presents the most important source of social, economical and health problems in many countries. The target of the present work was to accumulate data about the situation in the Czech Republic and particularly in the South-Bohemian Region. Alcoholism is a chronic, very frequently progressive disease, which can be even fatal. The alcoholism is typically caused by a physical dependence on the drug alcohol, but there is also a participation of genetic, psychological and social factors. Alcohol is a factor which brings a contribution to almost half mortalities in traffic accidents and which leads to many health problems. The scope of the article is aimed at the history of alcohol and its consumption, at mechanisms of biological effects of alcohol and origination of dependence and at health consequences of the alcohol consumption. Problems of relationships of man to alcohol are furthermore discussed in the article, and terms teetotaller (abstainer from alcoholic drinks), consumer, drunkard and person dependent on alcohol are explained, thus elucidating the point from which man becomes an alcoholic. A further part of the article is focused on alcohol in transportation and its contribution to the statistics of traffic accidents and on problems of drinking alcohol in pregnancy with explaining its danger for the developing foetus and elucidating the origination of foetal alcoholic syndrome. The data accumulated indicate that in the Czech Republic, 3/4 women drink alcoholic drinks before pregnancy, provided that one third of them continue drinking in the first three months of their gravidity. It is necessary to realize that drinking alcohol in pregnancy, particularly in the period when the woman yet does not know her pregnancy, presents a great risk for the foetus. This fact offers a big opportunity for improving information in young women. The article is also aimed at relationships between alcohol and criminality, since alcohol is a considerable criminogenic factor in offences against decency, but also in other types of delinquency and particularly in violent criminal offences. Alcohol takes part in traffic accidents to a great extent, particularly in the most severe accidents associated with fatal or severe injuries. Information presented in this review was taken from Czech special monographs focused on alcoholism, most recent international information from journals and statistical data of the Police of the Czech Republic.

The present work is aimed at summarizing knowledge and providing integral outline of problems of the hair analysis. It is particularly focused on its use in practice. It also offers the reader with an integral review of methods of carrying out tests of hair samples for the presence of certain substances. Last, but not least, it serves as a summarization of knowledge necessary for the hair analysis. The first part of the work deals with problems of the choice of the type of biological material for the analysis, particularly with the importance of the hair tissue and further alternative materials. The second part is aimed at the description of the mechanism of the incorporation of substances into the hair matrix. After these "theoretical" treatises, there is a description and discussion of methods of the hair analysis. Methods of the hair analysis are very interesting and even specialists cannot achieve agreement about a standard procedure. Thus, a general pattern has been established, according to which the analyses can be performed. General recommendations for methodical procedures are being issued by the society of hair testing. In accordance with these recommendations, particular methodical directions and procedures provided for given types of analyses are arranged. The last part offers an integral outline of the use of the hair analysis. In the literature, there are many conflicting and controversial facts. Not all the authors agree that the hair as an alternative biological material can have the same importance as for example the blood or urine, but when evaluating a wide spectrum of the use of the hair analysis, we can find that the hair is actually a very important type of samples. The determination of chemical substances or their metabolites in the hair tissue currently becomes a modern tool not only in forensic toxicology, but also in other branches of toxicology, such as e.g. "Human performance toxicology". In the Czech Republic, the use of the hair analysis is currently considered in association with investigation of traffic violations. Thus, it is obvious that requirements for knowledge of this problem increase not only among toxicologists, but also among specialists dealing e.g. with forensic practice.

For the detection of the toxic pollution over real time, so called biological early warning systems (BEWS) were developed. They are devices using living organisms as detectors of toxic pollution and comprising several parts: A water delivery system, an experimental chamber, an electronic or mechanical sensor (camera), from which the data measured are transmitted to an analyzer and alarm system, which will announce the toxicity found. The pollution monitoring is essentially continuous or it is performed repeatedly at very short intervals, time necessary for the detection is reduced to a minimum period, and the pollution detection is non-specific. For purposes of living biological detectors, fish, clams, water fleas and algae are most frequently used. The BEWS instruments were stepwise developed. Immobility or possibly death of the organism tested was first followed and latter applications were aimed at following changes in the behaviour and in physiologic parameters. BEWS are widely used for the on line monitoring of the toxic pollution. They are employed for monitoring the water quality and detection of accidents or deliberate pollution of rivers, following of water quality discharged from production enterprises, factories, waste water treatment plants and for monitoring the health non-harmfulness of water in water supply systems. The target of the work is to present basic data about problems of the BEWS and to make the reader familiar with the principle of the BEWS, with their possibilities and restrictions, with their use, principle of their function and with organisms used for their operation.

Cardiovascular diseases occur ever more frequently in younger age groups and thus, it is necessary to consider their prevention. One of risk factors leading to the origination of cardiovascular disease is high blood pressure, i. e. hypertension. Its occurrence in the population is increasing, the prevalence in childhood being between 1 and 10%. The blood pressure measurement is a simple, cheap method, which is effective if it is used appropriately. The purpose of the study was monitoring of individuals with blood pressure values in the region "High Normal". Total of 1 269 children at their age of 13 to 15 years participated in the study. In these children, the blood pressure was measured by the classical mercury tonometer and thereafter, in a sample of 95 children, it was determined based on ambulatory 24-hour monitoring. Results obtained from the measurement indicate that blood pressure values measured in children with the mercury tonometer in regions between the 90th and 95th percentiles, or possibly above the 95th percentile, should be verified with the help of ambulatory 24-hour monitoring at least three times every other month.

Ivabradine is a novel heart-rate-lowering drug that acts specifically on the sinoatrial node by selectively inhibiting the If current, which is the current prevalently responsible for the slow diastolic depolarization of pacemaker cells. Unlike many rate-lowering agents, ivabradine reduces heart rate in a dose-dependent manner both at rest and during exercise without producing any negative inotropic or vasoconstrictor effect. The bradycardic effect of ivabradine is proportional to the resting heart rate, such that the effect tends to plateau. Because ivabradine also binds to hyperpolarization, voltage-gated channels which carry the Ih current in the eye, transient, dose-dependent changes of the electroretinogram resulting in mild to moderate visual side effects may occur in approximately 15% of patients exposed to ivabradine. Ivabradine does not cross the cerebrovascular brain barrier and therefore, has no effect on the Ih current in central nervous system neurons.1 The safety of ivabradine was assessed in a development program that enrolled over 3,500 patients and 800 healthy volunteers in 36 countries from Europe, North and South America, Africa, Asia and Australia, 1,200 of whom being exposed to ivabradine for over 1 year. Ivabradine was associated with a good safety profile during its clinical development and its safety will be furthermore assessed by postmarketing surveillance and during on-going clinical trials. Ivabradine is the first selective and specific If inhibitor, which received marketing authorization in 27 European countries for the symptomatic treatment of chronic stable angina pectoris in patients with normal sinus rhythm who have a contraindication or intolerance of beta-blockers.

Influenza is a disease resulting in high morbidity and economical losses in all the labour spheres in the Czech Republic. In expert circles, it is a matter of general opinion that the vaccination with inactivated commercially available vaccines still before the influenza period is one of the most important anti-epidemic provisions against this infection. The vaccination in risk groups can considerably reduce the negative impact of possible influenza epidemic or pandemic not only on this group, but on the population as whole. Cases of death actually occur not only due to influenza but mainly due to its complications, the most important of them being secondary bacterial pneumonia or decompensation of pre-existing disease (cardiac, pulmonary, etc.). Most fatal cases due to influenza occur in elderly people, but all the age groups of the population are involved by this disease in the course of the influenza epidemics. The vaccination against influenza in the Czech Republic is focused on persons who belong to risk groups as specified in Regulation of Ministry of Health No. 439/2000 "On vaccination against infectious diseases". For the persons specified, the vaccination is free of charge. From July 1, Regulation of the Ministry of Health of the Czech Republic No. 225/2005 came in effect, according to which health insurance companies will cover vaccination against influenza for the following groups of persons: Inpatients over 65 years of age, inpatients after the splenectomy and transplantation of haemopoietic cells, inpatients who suffer from severe chronic and pharmacologically treated disease of the heart and blood vessels, airways or kidneys and inpatients with diabetes, as far as they are not vaccinated against influenza within the scope of regular or special vaccination in accordance with Regulation of the Ministry of Health No. 439/2000 Sb. "On vaccination against infectious diseases" in wording of latter regulations.

Elderly people form a great majority of clients of most clinical disciplines. They are a very vulnerable group, and in old age, there are frequent situations, which can present negative impacts on the human dignity. Of several concepts of the dignity, that one is most suitable for supporting professions, which is based on the awareness of being a part of the humankind. It is of importance that dignity must not be misinterpreted as a value and its survival. The dignity is a starting point for taking care of a "non-perspective" patient and an important part of taking care of elderly people with making them possible to survive their own dignity. In this way, the quality of taking care will be improved without further increasing of costs as well as the attitude of the personal taking care of elderly people to their jobs. The target of the existing EU project "Dignity and elderly citizens of Europe" is to explain factors that affect respecting of the dignity of elderly people and survival of their own dignity.

The publicity of the life of people with handicap in media is shown to be a very controversial phenomenon. On the one hand, it is of benefit, since it makes the majority society familiarized with the situation of handicapped individuals and induces a certain social reaction. On the other hand, media can suggest a general concept of nearly smooth and professionally provided condition in taking care of handicapped people.
Thus, there is an actual danger of a general lowering of the empathy and also sensitivity to abnormal situations - i. e. not only to the health involvement, but also to the violence and breaking of moral rules. In the human society, there is a natural need of the diversity fascinating the humans; its denial means a denial of the personal identity of each individual.
In this ambivalent attitude of the society to handicapped people, just the media could be considerably helpful - not by bringing enormous body of data on the life of handicapped people, but by mediating invitations for direct meeting of handicapped people with people without involvements.

Many osteoarthritis animal models have been studied, attempting to model these findings after those of humans. an animal model that could develop naturally occurring osteoarthritis in a manner similar to humans would be of great benefit for future research.
Studies with cynomologous macaques have shown that these animals develop naturally occurring osteoarthritis similar to that in humans. The goal of the current project was to examine the basic biomechanical characteristics of normal cynomologous macaque distal femoral articular cartilage as well as to develop a proper biomechanical testing protocol.
Testing was performed with the EnduraTEC machine. Using a 0.5mm radius non-permeable cylindrical indenter, instantaneous linear ramp compressions were applied to the cartilage specimens at a rate of 10 mm/sec to a depth of 0.15 mm. The thickness of the articular cartilage specimen was determined by using the needle probe. A load deformation curve was obtained and analyzed to determine the thickness.
Using a linear elastic model, we assumed that compression was instantaneous. Young's Modulus [N/mm2 = MPa] was calculated by plotting stress (load/cross-sectional area) vs. strain (displacement/thickness) and calculating the equation of the line. Stiffness [N/mm] was obtained by plotting load vs. displacement. Both were reached calculating the best-fit line form the speed compression ramp.
Only one previous published experiment attempted to characterize the biomechanical properties of normal cynomologous macaque monkey articular cartilage. Our study attempted to use a more simplified approach to calculate Young's modulus and stiffness. By assuming that the compression was instantaneous and using an impermeable indenter we were able to calculate what we feel are important biomechanical properties of articular cartilage.

The monitoring of drug levels has not only academic significance, but it also enables pharmacotherapy rationalization and protects the patient in case of high dose therapy often in the field of toxic doses that damage vital organs (kidney, heart, hematoporesis, mucous membranes etc.).
Therapeutic Drug Monitoring (TDM) is one of the means to increase safety and efficiency of pharmacotherapy, enabling dose adaptation to the individual patient. It is based on the possibility of fixing the drug concentration in biological liquids, most often in plasma or in urine, but also in saliva etc. TDM is a part of monitoring of treatment of chronically and critically ill patients. It is substantiated in patients with different pharmakinetics of drugs - older patients, newborns, children etc.
The monitoring of drug levels during therapy, or therapeutic drug monitoring, is complex analytic activity that, unlike simple drug analytics in biologic material (intoxication etc.), studies also other factors that are important with regard to dynamics of organism during illness and therapy.
The aim of monitoring of drug levels during pharmacotherapy is:
* analysis of drugs with narrow therapeutic range;
* application at drugs with well defined relation between drug concentration and effect (either therapeutic or toxic);
* analysis of drugs with great interindividual or intraindividual differences in pharmaceutical distribution or its clearance;
* to define the right regime and program of medication dosage for individual patients, i.e. individualization of pharmacotherapy;
* to reach optimally efficient drug concentration for therapy result;
* to forestall origin of toxic manifestations, e.g. gentamycine, digoxine, cyclosporine etc.;
* to follow continuously the changes during certain pharmacotherapy and to adapt it to current patient's condition and needs;
* to follow patient's compliance during the introduced therapy.

Situations can be encountered in the human life, in which a person pretends to be on the fringe of the society. He/she feels his/her elimination from the society to variable extent. Thus, the social rehabilitation is simultaneously a possibility of the consideration of the approach to re-integration of an individual into the society.

DDT is an organic chlorinated insecticide, formerly intensively used throughout the world in agriculture and in the control of insects transmitting malaria and typhus. In 1972, the use of DDT was prohibited in the USA and similarly also in some other countries. In many developing countries, DDT is ever being used in the control of mosquitoes transmitting malaria. DDT is considered as a persisting organic pollutant that shows its long-term presence in the environment and in animals that can be propagated to long distances. DDT is considered as probably carcinogenic substance by the World Health Organization. Due to its stability and ability to be accumulated in lipids, it was found in human typhus, and there is currently no organism throughout the planet that would not contain DDT. In spite of existing convincing experimental demonstrations of the carcinogenicity of DDT and of its main metabolites DDE and DDD, epidemiological studies are not demonstrable, with a prevalence of negative results. Further studies will be necessary concerning possible contributions of DDT to enhancing the risk of different types of cancer diseases and its possible negative effects on the endocrine system.