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A cytomorphometric analysis of superficial vaginal cells inwomen in three groups of different types of hormonal concentrationwas made. There were 15 women in each group. Group I was studiedduring a natural cycle, group II under oral contraceptive therapyand group III during an in-vitro fertilization (IVF) stimulationprotocol. Morphometric parameters were measured on an imageanalyser. The area, perimeter and several form factors weremeasured separately for nuclei and cytoplasm. The nucleus:cytoplasmicratio was also determined. The cytoplasmic area was significantlyreduced in group II and was associated with a statisticallysignificant reduction of the nuclear area. The nucleus:cytoplasmicratio appeared significantly increased in group II and reducedin group III. Low oestradiol impregnation obtained with an oralminidosed contraceptive interfered with vaginal cell maturation.High oestradiol concentrations obtained during IVF protocolsinduced marked nuclear pycnosis but did not induce supra-physiologicalcell enlargement. Maximal cell size is genetically regulatedaccording to Driesch's law of volume invariance and hormonalover-stimulation has no effect on cell size. The nucleus:cytoplasmicratio appears to be a powerful parameter reflecting the oppositeeffects of hormones on cell compartments.  相似文献   
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Group B beta-hemolytic streptococci were isolated from the throats of 49 of 1,110 patients who had pharyngitis. Compared with patients whose throat cultures were negative for beta-hemolytic streptococci, those harboring group B were more likely to have enlarged tonsils (P less than 0.001), exudate (P less than 0.02), and tender enlarged anterior cervical lymph nodes (P less than 0.01). Group B should not necessarily be dismissed as a nonpathogen when identified in the pharynx of patients with exudative pharyngitis; laboratories which report beta-hemolytic streptococcal isolates from the pharynx only as group A or non-group A should be encouraged to perform definitive group identification of all beta-hemolytic isolates to further evaluate the role of other streptococcal groups as the causative agents for pharyngitis.  相似文献   
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Summary The rigorous neo-Kraepelinean research criteria of the St. Louis/ Iowa and Taylor groups were applied to case record data of 116 first admissions of Schneider-negative schizophrenics—that is, those without first-rank symptoms (FRSs)—hospitalized in a strongly Schneider-oriented German University Psychiatric Clinic from 1962 to 1971. This sample had a total of 45.7% (53 cases) of psychiatric illness diagnosable by research methods. Indeed, only 31% (36 cases) of Schneider-negative schizophrenics turned out to have research-positive Kraepelin-oriented schizophrenia; and of these, 21 fulfilled both sets of research criteria for schizophrenia. It is important that 14.6% (17 cases) of Schneider-negative schizophrenia consisted of research-diagnosable affective disorder, with mania making up 5.2% and depression 9.4% of this figure. The findings suggest that a sample of Schneider-oriented schizophrenia without FRSs as routinely diagnosed in Germany does not seem to represent a clear-cut homogeneous and uncontaminated group of schizophrenics.  相似文献   
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Summary Recent studies have identified a group of patients with cytochrome oxidase (COX) deficiency presenting in infancy associated with a deficiency of mtDNA in muscle or other affected tissue (Moraes et al 1991). We used a novel approach to compare the level of mitochondrial (mtDNA) compared to nuclear DNA in skeletal muscle from a group of patients and controls, based on dot blots that were hybridized with a mtDNA probe labelled with35S[dCTP] and a reference nuclear DNA probe labelled with [32P]dCTP.The ratio of mtDNA to nuclear DNA varied in samples from different muscles of the same individual. Secondly, fetal muscle had very low levels of mtDNA compared to nuclear DNA, and data from older controls (cross-sectional rather than sequential) suggest that this increases rapidly over the first 3 months after birth and thereafter more slowly. Four patients with COX deficiency had levels of mtDNA that were below the age-specific range defined by normal quadriceps muscle. The clinical features of two of these patients were similar to earlier case reports of mtDNA depletion. In three patients the clinical course was relatively benign compared to cases that have previously been described.Levels of mtDNA in skeletal muscle from some patients with other forms of muscle disease were also found to be low, suggesting that mtDNA depletion, possibly related to depletion of mitochondria, may be a relatively non-specific response of muscle to various pathological processes. However, there does appear to be a distinctive group of young patients with reduced cytochrome oxidase activity in muscle, in whom marked mtDNA depletion reflects the primary defect.  相似文献   
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Respiratory chain deficiencies have long been regarded as neuromuscular diseases. In fact, oxidative phosphorylation, i.e., ATP synthesis by the respiratory chain not only occurs in the neuromuscular system, indeed, a number of nonneuromuscular organs and tissues are dependent upon mitochondrial energy supply. For this reason, a respiratory chain deficiency can theoretically give rise to any symptom, in any organ or tissue, at any age with any mode of inheritance, due to the twofold genetic origin of respiratory enzymes (nuclear DNA and mitochondrial DNA).  相似文献   
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