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991.
图形视觉诱发电位(P—VEP)是眼接受图形的刺激时,视路及大脑皮质枕区所产生的一系列电位变化。在视交叉后病变的诊断,病情估计及预后推测中有比较肯定的价值。 本文对17例视交叉后损害的病人进行分析。发现视交叉后病变以视皮质损害为主,表现为视物模糊,视力下降,视野改变。P—VEP检查的异常率与病变部位大小及病变性质有关。同时检查半视野刺激有助于提高阳性率。  相似文献   
992.
Microtubules were purified by using two cycles of assembly and disassembly processes on fresh brain homogenates from 30 guinea pigs. The yield was about 60 mg. The effect of tetrandrine on tubulin was determined by spectrophotometric analysis and electron microscopy. In addition, we used the indirect immunofluorescent method including tubulin antibody to locate the presence of microtubules in 3T3 cells by fluorescence microscopy. The effects of colchicine and P204 were studied for comparison at the same time. The results showed that colchicine can effectively depolymerize microtubules, while tetrandrine showed aggregation, and in a different manner. The shape and structure of microtubules were definitely destroyed by colchicine, but were not affected by P204 which protected against the destructive effect of tetrandrine. This result indicated the safety of using a combination of P204 and tetrandrine in the treatment of silicosis.  相似文献   
993.
Total hepatic protein synthesis was measured in vivo with a flooding-dose technique, and the production of total secreted proteins, albumin, complement component C3, and seromucoid fraction was measured in perfused livers of septic rats that received one of three different solutions infused intravenously; Group 1 received 16.4% dextrose; Group 2 received Aminosyn (25% BCAA) in 10.6% dextrose, and Group 3 received Freamine HBC (45% BCAA) in 10.6% dextrose. All solutions were isocaloric, and the amino acid solutions were isonitrogenous. The solutions were administered for 18 or 48 hours after the induction of sepsis. There were no significant differences in mortality rates in the three treatment groups. The negative nitrogen balance seen in the dextrose-infused animals was reversed to the same degree by the two different amino acid solutions. There were no significant differences in hepatic protein synthesis rates in vivo between the three groups of rats. Synthesis rates of secreted proteins in perfused liver were similar in the different treatment groups in the 18-hour experiments, whereas in the 48-hour experiments, synthesis rates of total secreted proteins, C3, and the serumucoid fraction were higher in Group 1 than in Groups 2 and 3. The results suggest that administration of an amino acid solution improves nitrogen balance in sepsis, but that this effect is not caused by stimulated hepatic protein synthesis. The nitrogen-sparing effect during sepsis of a branched chain amino acid (BCAA)-enriched solution does not seem to be superior to that of a balanced amino acid solution.  相似文献   
994.
纸板加压垫法治疗第五跖骨基底骨折113例临床分析   总被引:1,自引:0,他引:1  
本文报告我院应用纸板加压垫法治疗第五跖骨基底骨折113例,优良率达92.9%。本组无不愈合病例,对治疗要点和骨折分类进行了讨论,提出二类三度分型方法。用于指导治疗和估计预后,作者认为本病治疗不当可留有不同程度后遗症,应当重视其治疗。  相似文献   
995.
996.
Abstract  We previously demonstrated that cytomegalovirus (CMV) infection enhanced perivascular inflammation in rat aortic allografts. In this study, we investigated the relationship between the CMV infection load and the magnitude of perivasculitis (chronic rejection) in aortic transplants. Rats received or-thotopic abdominal aortic grafts, different degrees of total body irradiation (TBI) for immunosuppres-sion and CMV inoculation. The spleens of the rats receiving 5 Gy of TBI contained more infectious virus and viral antigens than those of rats receiving 3 Gy of TBI or no TBI. Although the number of inflammatory cells infiltrating the perivascular area was decreased after TBI, CMV infection resulted in increased perivasculitis in rats that received 5 Gy of TBI as compared to non-infected animals. This virus-induced effect was characterized predominantly by an increased T-cell infiltration, including CD4 and CD8 T-cells. It is concluded that an enhanced systemic CMV infection during severe immunosuppressive therapy can accelerate the development of chronic rejection, which seems to be mediated mainly by T-cells.  相似文献   
997.
C_3基因在BXSB小鼠主要脏器中的表达   总被引:1,自引:1,他引:0  
用同位素标记cDNA探针的分子杂交方法检测了BXSB小鼠肝、肾、脾、胸腺各脏器中补体C_3mRNA的表达情况,结果表明3~4月龄雄性BXSB小鼠肝、肾、脾各脏器C_3mRNA的表达量较正常对照鼠显著增加。C_3基因的过度表达可能参与BXSB小鼠SLE多脏器非感染性炎症的发生,同时提示该鼠存在M系统的大量扩增及活化。  相似文献   
998.
陈文祥  李健斋 《营养学报》1993,15(3):284-288
本文分析了我国5个地区4个民族共113名成年男性血清胆固醇酯脂肪酸组成及血脂水平。不同地区和民族人血清胆固醇酯脂肪酸组成的基本特点一致。但也有一定差异,这些差异与膳食性质有关。文中讨论了血清胆固醇酯脂肪酸组成与饮食脂肪的质和量及血脂水平的关系,并比较了我国与欧美国家人血清胆固醇酯脂肪酸组成。  相似文献   
999.
With Streptococcus pneumoniae, moxifloxacin was 4- and 10-fold more effective than levofloxacin at restricting selection of resistant mutants and at killing resistant mutants, respectively. The selection frequency for first-step topoisomerase mutants was 1,000 times lower for moxifloxacin than for levofloxacin; this difference was lost when second-step mutants were selected.  相似文献   
1000.
We wished to evaluate the efficacy and safety of a low and an intermediate daily dose of interferon-alpha2b (IFN-alpha2b) with didanosine in patients with acquired immunodeficiency syndrome (AIDS)-associated Kaposi's sarcoma (KS). HIV-seropositive subjects with biopsy-confirmed cutaneous KS were randomized to receive either a low (1 million IU) or an intermediate (10 million IU) dose of IFN-alpha2b once daily with twice daily doses of didanosine. Treatment assignment was stratified by CD4 count. Response, toxicity, changes in CD4 counts, and survival were evaluated. Sixty-eight eligible subjects were accrued, 35 to low-dose and 33 to intermediate-dose IFN-alpha2b. The response rate was 40% in the low-dose group (95% CI, 24-58) and 55% in the intermediate-dose group (95% CI, 36-72) (p = 0.338). The median response duration was approximately 110 weeks in both groups. Intermediate-dose IFN induced grade 3/4 neutropenia more often (21% vs. 3%, p = 0.048) and grade 3/4 toxicity faster (p = 0.0231) and necessitated treatment discontinuation earlier for drug-related toxicities (p = 0.0416) than low-dose IFN. There were no significant differences in survival between the treatment groups. Baseline CD4 count was the only significant factor predicting response. Once-daily low-dose and intermediate-dose IFN-alpha2b induced similar response rates, which were achieved without optimal antiretroviral therapy. The slightly higher response rate in the intermediate-dose group was offset by its significantly poorer tolerance. These findings justify the use of lower, well-tolerated IFN doses for treatment of KS with currently used antiretroviral regimens.  相似文献   
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