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PubMed1983

Cutaneous malignant melanoma: current views on pathogenesis, diagnosis, and surgical management.

Reliable cancer statistics reveal an unexplained increase in the incidence and rate of death from melanoma. Increased exposure to ultraviolet light does not seem to be a factor. Hormones may affect the incidence but do not influence survival. The recognition of the biologic evolution of different types of melanomas and the prognostic value of microstaging has had a major impact on the surgical management of cutaneous melanomas. Currently adequate excision is the only available curative treatment for melanoma and is most effective if performed on an early lesion. The extent of the excision should depend on the level of invasion and the bulk and location of the lesion. When clinically involved, dissection of the regional lymph nodes should be performed. The value of prophylactic node dissection of clinically uninvolved regional lymph nodes is unknown. Because of the low probability of regional lymph node involvement in thin lesions (less than 0.75 mm), prophylactic node dissection is not warranted. In contrast, there is a much higher incidence of spread to the regional lymph nodes reported in melanomas found to be thicker than 0.75 mm by microstaging. Prophylactic node dissection is probably worthwhile for these patients. Improved prospective randomized studies are needed to evaluate and determine the effectiveness of the various treatments that are being recommended.

Humans↗
PubMed1983

[The doctrine of immunity in the light of Robert Koch's concepts].

Robert Koch's epochal discovery of the tubercle bacilli provided the first complete evidence for the specific nature of the causative agents of the most important human infectious disease. It was on this basis that Koch developed his ideas about the doctrine of immunity. The high specificity of "Koch's basic experiment" became the cornerstone of the specific early recognition and prophylaxis of tuberculosis and provided a pattern of specific immune diagnostics in general. Basing on the antitoxin experiments of Behring and Ehrlich against diphtheria and tetanus, Koch presumed humoral immune mechanisms to exist also for tuberculosis. These investigations were abandoned after long-lasting efforts. The concept of Robert Koch and his school about the specific humoral immunity of infectious diseases was dominating immunological research for half a century until the elucidation of the cellular nature of the tuberculin reaction became a general asset of modern immunology. Only thereafter this discipline gave full swing from the immunochemical to the immunobiological approach. Robert Koch's merits as a physician and as an investigator reside in his strictly causal-analytical way of thinking and working which was adopted also in the search for the causes of cancer. In studying the immunological virus-host relationship one arrives from the "whence" of the disease at the "why" of its pathological form. This may be conceived of as a conceptual model for problems concerning the biological evolution and differentiation in modern pathology.

Allergy and Immunology↗
PubMedDate not supplied

[Pragmatic diagnostic value of hepatobiliary echography in 193 consecutive jaundiced patients referred to an endoscopic retrograde cholangiography center].

The aim of this retrospective work was to study the reliability of hepatobiliary sonography (SG) in a population of 193 icteric patients referred to our endoscopic retrograde cholangiography pancreatography (ERCP) unit between January 1980 and January 1983. One hundred and eight patients were female (ages varying from 9 to 90 years, average: 61 years) and 85 were male (ages varying from 9 to 91 years, average: 55 years). This study's objective was purely pragmatic. The initial SG report served as a basis for assessment of the diagnostic value of ultrasound examination. According to the sonographic patterns observed (biliary dilatation or not), jaundice was classified as intra- or extrahepatic. The sonographic results were then compared to the definitive diagnosis as determined from clinical, biological and pathological data. In the case of an obstacle, the final diagnosis was confirmed by either ERCP or laparotomy. When ERCP showed no obstruction, the final diagnosis was based on either percutaneous hepatic biopsy or clinical and biological evolution and in two cases, an autopsy findings. In this population and considering the pragmatic context of the study, the effectiveness of SG in classifying jaundice as extra- or intrahepatic was 76 p. 100 (70-82), the sensitivity was 75 p. 100 (67-83), specificity, 81 p. 100 (72-89), positive predictive value, 87 p. 100 (81-93) and the negative predictive value, 66 p. 100 (56-76). Sixty-seven p. 100 of the 30 false negative diagnoses in 120 cases of obstructive jaundice corresponded to misdiagnosis of cholelithiasis. SG was able to suggest the etiology of jaundice in 94 cases; this was correct in 58 cases (61 p. 100).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1978

Some aspects of monogenean existence.

This paper deals with some ecology and evolution problems of monogeneans--gill parasites of fishes, such as congeneric simultaneous doublets, spatial distribution of species on the gills, interspecific restrictions of biotopes etc. The author proves competitive character of site selection in monogeneans. The role of hermaphroditism in the evolution and biology of monogeneans, and morphological adaptations (mainly androgynous) directed to increasing of mating chance are discussed. The author concentrates on analyzing the cases of monoxenous distribution and speciation and also on examining the concept of symxenity and alloxenity. He attaches great importance to ecological and evolutionary investigations of Monogenoidea.

Animals↗
PubMed1980

Blood polymorphism frequencies in the Tofinu, the "Water Men" of Southern Benin.

Informations on the genetic constitution (AcP, EsD, PGM1, AK, 6-PGD, Hb, Hp, Cp and Gc blood systems) of the Tofinu, a lacustrine population living in the pile-work of the Guinean coast (Southern Benin), are reported. The Tofinu gene frequencies are much as would be expected from the geographical position of this country. The AcP, Hp and Hb beta gene frequencies are compared with those of the other ethnic groups of Southern Benin as the Goun, Fon, Djedje, and Nago, using the contingency chi-square test of homogeneity. On the average, the five groups do not show any significant differences. Thus it results that there seems to be a common genetic origin and that the cultural-linguistic differentiation followed the evolutive biological process for the populations of this country.

Benin↗