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Atypical spermatogonia are relatively frequent in the vicinity of testicular teratomas or seminomas. These voluminous cells are seminoma-like, showing broad and clear cytoplasm borders, big nuclei and peculiarly enlarged nucleoli. Atypical spermatogonia usually line the tubules and displace the remaining Sertoli cells towards the middle of the tubules. Recently, such atypical spermatogonia have been described in testicular biopsies performed for fertility disturbances. Two patients showing atypical spermatogonia developed, years later, malignant testicular tumors. Therefore, were checked all of our histological specimens from testicular biopsies over the period 1950-1976 for atypical spermatogonia. They originated from 1935 adult patients in whom biopsy had been performed, in general bilaterally, for fertility disturbances. In fact, atypical spermatogonia were found in the specimens of 9 patients, that is, 0.55%. Five of these patients developed malignant testicular tumours within periods ranging from months to six years, viz. three seminomas, one teratoma and one combined tumor, i.e. a teratoma and seminoma. The remaining four patients with atypical spermatogonia have shown no sign of tumor to date. As the results of our investigation show, atypical spermatogonia in testicular biopsies should not be taken lightly. We therefore strongly advise checks at short intervals on such patients in view of the high risk of their developing malignant testicular tumors.  相似文献   
243.
AIMS AND BACKGROUND: Ifosfamide is an active alkylating agent in the treatment of breast cancer, as a first-line therapy and in advanced disease. Since the combination of etoposide with an alkylating agent produces a synergistic and tolerable activity in various malignancies, in the present study, ifosfamide and etoposide were administered to patients with advanced breast cancer to evaluate the response characteristics and the toxicity profile. STUDY DESIGN: The combination of ifosfamide, mesna and etoposide was prospectively administered to 41 previously treated patients with stage IV breast carcinoma. The treatment schedule consisted of ifosfamide, 1500 mg/m2, infused over 24 hrs with 1500 mg/m2 mesna on days 1 to 5 and 120 mg/m2 etoposide, infused over 1 hr on days 1 to 3, to be repeated every 4th week. RESULTS: After a median follow-up of 10 months, an objective response rate of 23% (overall 2.5% complete remission and 20.5% partial remission) and a median response duration of 5.3 months were obtained in 39 assessable patients. The non-responder group consisted of 28.3% stable disease and 48.7% progressive disease. The prior status of chemotherapy was the only significant prognostic factor with an impact on the response rate. The overall toxicity was generally mild, with grade 3 myelotoxicity encountered in 25.7% of patients. CONCLUSIONS: The tolerable side effect profile of the ifosfamide and etoposide combination might be advantageous as regards the quality of life. To improve the rate and/or the duration of response and to clarify the precise role of the ifosfamide-etoposide combination in previously treated advanced breast cancer, further trials are warranted.  相似文献   
244.
In previous studies, depression has been associated with both marital status and marital distress. Unfortunately, given the cross-sectional design of most of this research, the temporal nature of these associations is unclear. The authors examined the marital functioning of young adults as a function of whether they received psychiatric diagnoses of major depressive disorder or nonaffective psychiatric disorder during adolescence. Depression during adolescence was found to predict higher rates of marriage among younger women and subsequent marital dissatisfaction. This pattern of results appears to be specific to depression: The presence during adolescence of a nonaffective psychiatric disorder was unrelated to subsequent marital functioning. These findings highlight the potentially adverse consequences of depression in adolescence and underscore the importance of prevention and early treatment efforts.  相似文献   
245.
Thrombomodulin (TM) is a thrombin receptor on the endothelial cell surface, effective as an anticoagulant by changing procoagulant thrombin to an anticoagulant one. As rabbit TM with glycosaminoglycan (GAG) has a more potent anticoagulant activity than that without GAG, we expressed recombinant GAG-modified urinary thrombomodulin (GAG-UTM) in C-127 cells. The effect of an additional GAG chain on anticoagulant activity was investigated in comparison with unmodified recombinant UTM (r-UTM). In vitro, the activity of cleavage of fibrinogen by thrombin or prothrombinase activity was more potently depressed by GAG-UTM than by r-UTM, and the generation of activated protein C by TM-thrombin complex was accelerated by GAG modification. The acceleration of antithrombin III-dependent anticoagulant activity was shown only by GAG-UTM. Parameters like thrombin time, prothrombin time and activated partial thromboplastin time in human plasma were prolonged by GAG-UTM more than by r-UTM. In vivo, the effect of GAG-UTM and r-UTM in endotoxin-induced disseminated intravascular coagulation (DIC) rats was investigated using hematological parameters. GAG-UTM and r-UTM significantly reduced the decrease in fibrinogen and platelet number induced by endotoxin at the dosage of 0.1 and 1.0 mg/kg/h, respectively, suggesting that the antithrombotic effect of GAG-UTM in endotoxin-induced DIC rats was 10-fold as potent as that of r-UTM. GAG-UTM reduced the prolongation of the bleeding time induced by endotoxin, while r-UTM accelerated it. These results suggest that the addition of a GAG chain may increase availability as an anticoagulant.  相似文献   
246.
Base-boronated nucleoside and phosphate-boronated nucleotides were potent hypolipidemic agents in rodents, lowering both serum cholesterol and triglyceride levels. Rat VLDL and LDL cholesterol levels were generally reduced and HDL cholesterol levels were significantly elevated after 14 days dosing at 8 mg/kg/day. Tissue cholesterol, triglyceride and phospholipid levels were reduced by selected derivatives. Increased fecal excretion of lipids did not appear to be a mechanism by which these derivatives lowered serum lipids in rodents. Rather, the agents suppressed appetite and reduced the activities of rate-limiting enzymes for de novo lipid synthesis, specifically cytoplasmic acetyl CoA synthetase, squalene synthetase, and phosphatidylate phosphohydrolase with IC50 values of approximately 10(-5) m.  相似文献   
247.
Human papillomaviruses are a common human pathogen responsible for diseases varying in severity from warts to cervical cancer. This article examines the functions of the viral gene products and how they interact with cellular factors to replicate themselves and cause disease.  相似文献   
248.
Sepsis is reported to induce an increase in the rate of apoptosis (Ao), in immature lymphoid cells residing in hematopoietic tissues such as the thymus and bone marrow. Alternatively, secondary lymphoid tissue, such as the spleen exhibit little innate (unstimulated) Ao. However, it is unknown whether or not polymicrobial sepsis has any effects on the frequency of Ao in mucosal lymphoid tissue and what, if any, are the functional consequences of such a change. To assess this, Peyer's patch cells were harvested from C3H/HeN (endotoxin-sensitive) mice killed 12 or 24 hours after the onset of polymicrobial sepsis (cecal ligation and puncture [CLP]). The results indicate that the percentage of cells that were Ao+ as determined by flow cytometry were markedly increased at 24 hours, but not at 12 hours post-CLP. This correlates well with evidence of increased DNA fragmentation as well as histological changes observed both at a light and transmission electron microscopic level of the Peyer's patch Ao. Phenotypically, these changes were restricted to the B220+ (B-cell) population that also exhibited a marked increase of Fas/Apo-1 antigen expression. The functional consequence of this increased apoptosis appears to be associated with the endogenous stimulation (activation) of IgA production by mucosal B lymphocytes and increased nuclear c-Rel expression. Furthermore, we found that Peyer's patch lymphocytes isolated from C3H/HeJ-Faslgld (endotoxin-tolerant/Fas ligand- [FasL] deficient) as opposed to C3H/HeJ (endotoxin-tolerant) inbred mice did not exhibit increased Ao after CLP. These findings indicate that increased B-cell Ao appears to be a FasL-Fas antigen-mediated process, but is not due to endotoxin sensitivity. In conclusion, we speculate that the increased Fas-associated apoptosis detected in mucosal B cells (as opposed to splenic or bone marrow B cells) may be due to increased luminal antigens other than endotoxin, released due to gut barrier integrity breakdown during sepsis.  相似文献   
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Gaseous insufflation of oxygen via the venous vascular system is thought to be an useful tool for preventing anoxic tissue injury during extended time periods of ischemic preservation and for allowing for an improved recovery of organ function after transplantation. The present study aimed at the application of a noninvasive technique for monitoring effectiveness and homogeneity of gaseous areation by using an epiillumination microscopic technique for assessment of tissue nicotinamide adenine dinucleotide (NADH) fluorescence. Rat livers were flushed with and stored in University of Wisconsin solution at 4 degrees C for 48 h (n = 20). In half of the experiments (n = 10) gaseous oxygen was applied subsequent to organ harvest. Using ultraviolet-excitation high-resolution microscopy and computer-assisted image analysis liver surfaces were scanned for NADH intensity and spatial heterogeneity at 1, 24, and 48 h preservation time. Livers simply stored without aeration served as controls (n = 10). NADH intensity data were compared with corresponding data of tissue adenosine triphosphate (ATP) concentrations determined enzymatically. NADH fluorescence already differed at 1 h preservation between the two groups with significantly lower values in the aerobically stored livers. NADH fluorescence further decreased between 1 and 24 h preservation and remained low until 48 h, whereas in the anaerobically stored livers NADH fluorescence was found to be constantly high over the entire observation period. Aerobic storage resulted in rather homogeneous tissue oxygenation with an intrahepatic variation of NADH fluorescence <20%. In parallel, oxygen persufflation appropriately restored tissue ATP content within 1 to 24 h of preservation, while the simply stored livers exhibited pronounced depletion of ATP. We demonstrate for the first time that by means of retrograde gaseous oxygenation, ischemic livers can be readily and effectively oxygenated. Our study further indicates that the noninvasive microscopic analysis of tissue NADH fluorescence may be an useful tool for estimating efficiency of strategies in organ preservation.  相似文献   
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