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The karotypic patterns of 15 retinoblastomas were examined. Five tumors were found to have two distinct stem lines and, therefore, the chromosomal patterns of 20 tumor cell lines are reported. Three nonrandom chromosomal changes, namely, a loss of a chromosome #13, the presence of an i(6p), or a trisomy of 1q were observed. The potential importance of these chromosomal changes in tumor development is discussed, particularly the loss of a chromosome #13 or the gain of an i(6p). At least one of the three chromosomal changes was found in 75% of the tumor lines analyzed.  相似文献   
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Recent findings challenge the belief that most cases of impotence are psychogenic. Research indicates that nocturnal penile tumescence (NPT) can be viewed as a biologic marker for physiologic erectile capacity. Thus, the test can help to distinguish between physicogenic and psychogenic impotence. To determine proximal causes of erectile failure, other evaluations are easily performed during NPT monitoring.  相似文献   
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R Yassa  V Nair  G Schwartz 《Psychosomatics》1984,25(2):135-138
Over 300 patients were assessed for the presence of tardive dyskinesia in relation to the primary psychiatric diagnosis. Patients with organic mental syndrome or bipolar disorder showed a significantly (P < .01) higher prevalence of tardive dyskinesia (41% and 42%, respectively) than did those with schizophrenia (24.5%). This difference was not related to age or duration of neuroleptic treatment. Based on these findings, the physician should remain aware of the greater possibility of tardive dyskinesia in patients with organic mental syndrome or bipolar disorder and periodically review dosage and indications for neuroleptic treatment.  相似文献   
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DRw6 has been difficult to define serologically. In the present experiments we have developed T cell lines in order to characterize the components of a DRw6 haplotype. This was accomplished by priming T cells with allogeneic mononuclear cells mismatched for DRw6, Dw6, and MT2. Subsequently, three sublines with distinct reactivity patterns were derived by limiting dilution. The specificities detected by these sublines included: (a) a specificity found on a subset of cells positive for DRw6 which was inhibited by monoclonal antibodies against DS(DC), the human homologue of the murine IA-encoded molecules, (b) another DRw6-associated specificity blocked by an MT2-like antibody, and (c) an MT2-like specificity blocked by monoclonal antibodies reactive with a different MT2-associated determinant. These results show that more than one IE-like, as well as the DS/DC (IA-like) molecules, carry distinctive antigenic epitopes that can be recognized by allogeneic T cells. Primed T cell lines may be useful for a better definition of certain haplotypes which are at present difficult to characterize with serological reagents alone.  相似文献   
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Vascular access through subcutaneous prosthetic arteriovenous fistulas was studied in eighteen dogs. Dacron velour and woven Dacron grafts (6 mm diameter) were constructed across the lower abdomen between the common femoral artery and the opposite common femoral vein. In heparinized animals 197 percutaneous punctures were made with a "14 guage hemodialysis cannula at weekly intervals. Over a period of one and a half years there was no instance of infection. One of the fourteen Dacron velous and all four woven Dacron fistulas thrombosed. These data suggested the feasibility of achieving repetitive blood access through Dacron velour vascular prostheses. Nineteen Dacron velour fistula bypasses between the brachial artery and median basilic vein were performed in fifteen selected patients for a total dialysis period of ninety-six months. Failed standard subcutaneous fistulas or absence of suitable vessels in the upper extremity were indications for the primary procedure. Of three looped forearm fistulas, two thrombosed at twenty-two and two months. Complications among sixteen straight bypasses in the arm included two graft infections and one cannula tract infection. There were no instances of thrombosis in this group. The advantages of single needle dialysis in these high risk patients have been emphasized. Eleven grafts are presently functioning two to nine months postoperatively. Our preliminary results suggest that a Dacron velour fistula merits consideration as an alternative for vascular access in maintenance hemodialysis.  相似文献   
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目的 探讨化合物N - 2 2 11对大鼠局灶性脑缺血再灌注损伤的保护作用。方法 应用大脑中动脉阻塞再灌模型(MCAO),观察并对比脑缺血大鼠给药组和模型组的指标。结果 化合物N - 2 2 11灌胃给药能使脑缺血大鼠的神经行为明显改善,脑梗死面积显著降低;该药还能提高组织清除羟自由基的能力,高、中、低三个剂量组与缺血模型组相比均有显著性差异。结论 化合物N - 2 2 11具有脑保护作用,其作用机制可能与抗氧自由基作用有关。  相似文献   
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