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91.
Small cell tumors of the ovary are uncommon but represent an important group to recognize in the differential diagnosis of primary and metastatic ovarian neoplasms. In some cases the correct diagnosis cannot be confidently made on the basis of clinical setting, routine light microscopy, and immunohistochemistry, and electron microscopy may be supportive or definitive in establishing cell type. The cell type is often important in choosing optimal therapy and in predicting prognosis. The authors performed electron microscopy on a moderate number of ovarian small cell tumors and here describe and illustrate the diagnostic features of representative examples of various types. The ultrastructural features of the metastatic tumors, such as embryonal rhabdomyosarcoma, neuroblastoma, and melanoma, are identical to those of their respective primary tumors, are well known, and usually pose no problem in diagnosis. On the other hand, the ultrastructural features of some primary ovarian small cell tumors may present a more difficult differential diagnosis, because they have features that are subtle and/or in common. Exemplary of tumors in this category are diffuse adult granulosa cell tumor, endometrial stromal sarcoma, and small cell carcinomas of the hypercalcemic and pulmonary (oat cell) types. Distinguishing among them may be difficult but is possible, and electron microscopy may be a valuable supplement to the diagnostic information obtained from the clinical presentation, light microscopy, immunohistochemistry and, in some tumors, cytometric analysis of these neoplasms.  相似文献   
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One hundred consecutive patients (81 male and 19 female) with unstable angina pectoris undergoing coronary angiography were divided according to Braunwald's clinical classification. Seventeen (17%) patients had new onset angina (class I), 68 (68%) sub-acute angina (class II) and 15 (15%) had acute rest angina (class III). Twenty-seven (27%) patients had secondary unstable angina pectoris (class A), 49 (49%) primary unstable angina (class B) and 24 (24%) had post-infarction unstable angina (class C). ST-T wave changes on ECG were present in 54 (54%) while absent in 46 (46%) patients. On coronary angiography, 26 (26%) patients had single vessel disease, 30 (30%) double vessel disease and 39 (39%) patients had triple vessel disease. Five (5%) patients were found to have normal coronaries. Classification of patients according to Braunwald's clinical classification showed single vessel disease to be higher in class I as compared to class II (47% vs 22%; p = 0.04) and classes III (47% vs 20%; p<0.01). Single vessel disease was found to be higher in class C as compared to class B (41.7% vs 16.4; p = 0.01). Double vessel disease was higher in class B as compared to class A (40.8% vs 18.5%, p = 0.04). Triple vessel disease incidence was not found to be significantly different among different clinical classes. Morphology of coronary artery lesions was classified according to Ambrose's classification. Out of the total of 248 lesions in the whole study group, there were 68 (27.42%) concentric lesions, 55 (22.18%) eccentric type I lesions, 23 (9.27%) eccentric type II lesions, 42 (16.94%) multiple irregularity lesions and 60 (24.19%) totally occluded lesions. Concentric lesions were found to be higher in class C as compared to class B (40% vs 19.8%; p = 0.014). Statistically significant difference was not present in the distribution of other morphological type of lesions among different clinical classes. In the whole study group, intra-luminal thrombus was found to be present in 17 (17%) of patients. Distribution of intra-luminal thrombus according to Braunwald's classification showed that none of the patients in class I had intra-luminal thrombus, while 13 (19.1%) patients in class II and 4(26.7%) in class III had intra-luminal thrombus. The difference in the occurrence of intra-luminal thrombus between class I and class II (p = 0.004) and class I and class III (p = 0 .03 was found to be significant. Thus, majority of patients undergoing coronary angiography had primary sub-acute rest angina. Single vessel disease was higher in new onset angina. Patients with unstable angina pectoris and ST-T changes on ECG had higher number of lesions per patient and higher eccentric type I lesions. Intra-luminal thrombus was more frequently encountered with acute rest angina. However, the distribution of different morphological type of lesions on coronary angiography did not differ significantly in different clinical classes of unstable angina pectoris divided according to Braunwald's classification.  相似文献   
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A trajectory defined by three time-ordered events was offered as a useful adjunct to building a development theory about antisocial behaviors. A sequence was defined with significant linkages between antisocial childhood behavior and early arrest and between early arrest and chronic offending. The majority of chronic offenders traveled through all three events in the sequence. Each event in the sequence shared a common process of disrupted family process plus frequent family transitions and marked social disadvantage. The findings support the hypothesis that the process that leads to antisocial behaviors at grade four may also maintain the entire sequence. The level of disrupted process at initiation and a time-based measure of involvement with deviant peers predicted which individuals moved forward in the sequence and which did not. The findings are consistent with the idea that the majority of chronic offending juveniles follow a trajectory that can be explained by a single theory.  相似文献   
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The role of epithelial and stromal progesterone (P) receptors (PR) in the regulation of uterine epithelial DNA synthesis by P was investigated by analyzing the four types of tissue recombinants prepared with uterine stroma (S) and epithelium (E) from wild-type (wt) and PR knockout (PRKO) mice: wt-S + wt-E, PRKO-S + PRKO-E, wt-S + PRKO-E, and PRKO-S + wt-E. 17-Beta estradiol (E2) stimulated DNA synthesis in all four types of tissue recombinants. On the other hand, P inhibited E2-induced DNA synthesis only in tissue recombinants prepared with wild-type (PR-positive) stroma (wt-S + wt-E or wt-S + PRKO-E) but not knockout (PR-negative) stroma (PRKO-S + wt-E or PRKO-S + PRKO-E). These results clearly demonstrate that the inhibitory effect of P on uterine epithelial DNA synthesis is mediated by stromal PR. Epithelial PR is neither necessary nor sufficient for P inhibition of E2-induced epithelial DNA synthesis.  相似文献   
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In light of recent studies showing that prostate-specific antigen (PSA) complexes with certain blood proteins, we studied the effects of acute-phase reactants and alpha 2-macroglobulin (A2MG) on serum concentrations of PSA. Serum samples were obtained from 419 men admitted to an acute-care facility. Various acute-phase reactants-including C-reactive protein, alpha 1-acid glycoprotein, alpha 1-antitrypsin, and alpha 1-antichymotrypsin-and A2MG were measured with a Beckman Array analyzer in parallel with determinations of PSA concentrations by two methods, the Hybritech Tandem RIA and the Abbott PSA IMx. Evaluation by Spearman rank correlation revealed a significant negative correlation of A2MG with PSA values (P < 0.01) and (as expected) a positive correlation of age with PSA values (P < 0.001). The former correlation suggests the possibility that patients with high serum concentrations of A2MG may give falsely decreased results for PSA concentrations in serum.  相似文献   
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