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931.
Involvement of the mononuclear phagocyte system in the mechanism of resistance to Corynebacterium kutscheri was studied in C57B1/6 and Swiss Lynch mice. A major difference between the two mouse strains was that the phagocytic cells of the livers of C57B1/6 mice destroyed the bacteria with much greater efficiency. There was no evidence of serum factors which might have led to this greater bacterial killing observed in the C57B1/6 mice, and in vivo phagocytosis of C. kutscheri was identical in both mouse strains. Resistance to C. kutscheri could be transferred with spleen and/or bone marrow cells from resistant (Swiss Lynch X C57B1/6) F1 mice to 650-rad irradiated susceptible Swiss Lynch mice. Nonspecific and acquired mechanisms of resistance to C. kutscheri are discussed.  相似文献   
932.
A "problem solving case" method of teaching practical pathology is described, illustrated and compared with more traditional teaching methods. This method offers many advantages-the most important being that it shows the effect of pathological lesions in an actual patient, thus emphasizing the relevance of pathology to clinical medicine. Other advantages are that self-assessmetn is encouraged; guidance is given on the depth of knowledge expected from a student; student response is favourable; no elaborate or expensive equipment is required; the method is economic in the use of staff time, and it is very flexible in use in terms both of time and place.  相似文献   
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The authors studied antibodies to the nervous tissue in the blood (pair serum with an interval of 10 days) and in the CSF in 155 patients with epidemic parotitis and signs of neurotoxicosis, parotit meningitis and meningoencephalitis. Depending upon the intensivity of antibody elaboration 3 groups were distinguished. The first group (40 cases), with a high content of antibodies to the nervous tissue, was characterized by a prevalence of encephalitic forms (in 30 of the 40 cases). In the second group (32 cases) with a less antibody content there was a prevalence of meningitis, while meningoencephalitis was seen only in 3 cases. The third group (83 cases) with a low concentration or absence of antibodies was characterized by a mild course of the disease. This group included as well patients with neurotoxicosis. These data may indicate involvement of allergic mechanisms of a retarded type in the pathogenesis of remote lesions of the nervous system in epidemic parotitis.  相似文献   
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Specific types of alopecia can be readily identified by history and physical examination with a high degree of accuracy in 97% of cases. Although some confirmatory laboratory studies may be required, two elements of the medical history and four elements of the physical examination can lead a dermatologist knowledgeable in the common scalp diseases to a rapid diagnosis. The key elements of history are age and duration of alopecia. The key elements of the examination are scalp status, pattern of loss, pull test results, and the integrity of the follicular units.  相似文献   
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