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31.
高奉浔 《中国人民解放军军医大学学报》1989,(1)
Eight cases of mesenchymal chondrosarcoma either of skeletal(5 cases) or extrasketetalorigin (3 cases) are reported. According to histopathological and diagnostic criteria,mesenchymal chondrosarcoma were classified into two types cartilage isiand cell type andundifierentiated small cell type It is believed that the application of this classification in the study ofmesenchymal chondrosarcoma is helptul the estimation of its malignancy and choice of treatmentas well al in the prediction of its prognosis. Mesenchymal chondrosarcoma is a highly malignant neoplasm with poor prognosis. None ofthe patients in this series survived more than five years after they were diagnosed. The diffentialdiagnosis of malignant lymphoma, chondrosarcoma, hemangiopericytosarcoma, etc. was discussed.My data support the assumption that mesenchymal chondrosarcoma originates from the secondarymesenchyme rather than the primary mesenchyme. 相似文献
32.
对人胎儿前庭器超微结构的研究,国内外报道甚少。本文对18至36周人胎儿颞骨10具进行了扫描电镜和透射电镜的观察,并对应用Surface preparation法制做人胎儿前庭器标本的方法进行了探讨。本文观察所见:豚鼠平衡斑的生理状态与人胎儿很近似,体面积比人胎儿平衡斑小,感觉毛长,细胞排列更整齐。28周以后的胎儿因前庭周围骨质变硬,制做标本时可以分别取出两囊斑和壶腹嵴。 相似文献
33.
全国细菌药敏试验的室间质量评价 总被引:1,自引:0,他引:1
目的:了解全国大中型医院细菌药敏试验(AST)状况,提高检测水平和质量。方法:定期向全国各参加评价实验室发放冻干标本,要求在规定时间内报告可疑感染的病原菌及其药敏结果,对回报结果给予数据统计、分析和评价。结果:2000年全国489个细菌室对常见耐药菌的检测正确率分别为:超广谱β-内酰胺酶63%(ESBLs);苯唑西林敏感金黄色葡萄球菌(MSSA)74%;苯唑西林耐药凝固酶阴性葡萄球菌(MRSCoN)48%;对青霉素不敏感肺炎链球菌7%;氨基糖苷类高水平耐药肠球菌95%;产β-内酰胺酶流感嗜血杆菌正确率35%。结论:通过细菌药敏试验的室间质量评价反映出我国的细菌耐药性检测水平急待提高。 相似文献
34.
对32例出血性梗塞研究分析,发现常出现于脑栓塞及大面积脑血栓病人。以治疗中病情突然加重或持久症状不改善为特征,动态CT检查对本病的诊断及治疗有重要意义。 相似文献
35.
Exposure of cultured cerebellar granule cells to glutamate results in a concentration-dependent (EC50 = 22.7 +/- 0.4 microM) and delayed (24-72 hr) neurotoxicity, which is blocked by the specific N-methyl-D-aspartate (NMDA) receptor antagonists 2-amino-5-phosphovalerate and MK-801 but is unaffected by the non-NMDA receptor antagonists 6-cyano-7-nitroquinoxaline-2,3-dione and 6,7-dinitroquinoxaline-2,3-dione. Although glutamate toxicity in these cells is mediated by the NMDA subtype of glutamate receptor, pretreatment of cerebellar granule cells with subtoxic concentrations of NMDA markedly antagonizes the neurotoxic actions of glutamate, with an IC50 of 55 +/- 4 microM. The neuroprotective effect of NMDA requires a preincubation time of approximately 120 min to be fully manifested and does not require the presence of NMDA during glutamate exposure. These data demonstrate that NMDA receptors mediate both neurotoxicity and neuroprotection in cerebellar granule cells. Among four glutamate receptor agonists tested (NMDA, quisqualate, ibotenate, and kainate), only NMDA was able to provide a robust neuroprotection against glutamate toxicity. Quisqualate was neither neurotoxic nor neuroprotective, whereas ibotenate, which was nontoxic by itself, induced a small degree of neuroprotection. In contrast, kainate, which was neurotoxic to cerebellar granule cells, also provided considerable neuroprotection against glutamate toxicity. Because preincubation of cerebellar granule cells with NMDA fails to alter NMDA receptor-mediated phosphoinositide hydrolysis or the specific binding of [3H]MK-801 to NMDA receptors, it appears that the neuroprotective effects of NMDA are not due to NMDA receptor desensitization. 相似文献
36.
TuberculosisandSchistosomiasisarethemajorcontagiousdiseaseswhicharethemostdangeroustothepeople’shealth Inordertogetridofthem ,wemustlookforamoreusefulvaccine Bythetech niquesofmolecularbiology ,2 6 0 0 0DaGlutathionStransferase (GST) genewasclonedintotheE coli MycobacteriumtransferringandexpressionvectorpBCG 2 0 0 0totransformittoMycobacteriumsmeg matismc2 15 5 (MS)andBCGseparatelyinordertoconstructrMS Sj2 6GSTvaccineandrBCG Sj2 6GSTvaccine Inthisstudy ,theBALB/cmicewereimmu niz… 相似文献
37.
国产达美康治疗Ⅱ型糖尿病的临床观察 总被引:1,自引:0,他引:1
本文应用国产达美康对71例NIDDM患者进行了临床观察,同时以优降糖做对照。结果显示:达美康降糖效果与优降糖相当,降血脂方面优于优降糖,并可降低全血粘度,而对照组无此变化,提示达美康在降低血粘度、改善微循环、防治糖尿病性微血管病变上有它独特的作用。结果表明达美康是治疗NIDDM安全而有效的口服降糖药。 相似文献
38.
肢体不同延长速度对局部血流量的影响 总被引:1,自引:1,他引:0
本文报告20只兔胫骨以不同速度延长时用末梢微循环测定系统动态连续监测局部血流量变化的结果,发现一次延长>1 mm时,局部肌肉血流量开始急骤下降,恢复延长前血流量所需的时间>8 h。作者认为肢体的血管、肌肉等组织对1 mm/次/d延长速度有相当大的生物适应性。延长速度>1 mm/次/d易造成局部血流量大幅度减少。延长肢肌肉萎缩、肌力减弱可能与血流量减少有关。 相似文献
39.
应用非同位素标记PCR-SSCP技术对34例大肠癌组织p53基因第五外显子突变进行了检测。结果:50%(11/22)结肠癌,8.3%(1/12)直肠癌存在p53基因突变,低分化腺癌高于高、中分化腺癌(P<0.05),DukesB、C期高于DukesA期(P<0.05),p53基因第五外显子突变在已发生淋巴转移的大肠癌组织中呈现较强的趋势。提示:检测结肠癌原发灶p53基因第五外显子突变,对指导结肠癌的诊断、治疗及预后判断具有一定意义 相似文献
40.
Ocular injuries from accidental laser exposure 总被引:3,自引:0,他引:3
This report presents 29 cases of ocular injury (31 eyes) caused by accidental laser exposure. Twenty-eight eyes were injured during laser adjustment and alignment. Nineteen eyes were damaged by Q-switched lasers at a wavelength of 1064 nm. Macula damage occurred in 25 eyes. During the early phase after injury, there were different degrees of retinal coagulation, edema or hemorrhage in exposed spots and there occurred immediate reduction of visual acuity. Effusion of blood and exudate was absorbed in most injured eyes under treatment lasting several weeks; meanwhile, gray-white scars appeared. Macular holes appeared in seven cases a week after injury, thus extending the course of the injury. Nine cases (10 eyes) were followed-up for 4-10 y, during which time the condition of eight cases (nine eyes) remained stable. The causes of the laser accidents and the relationship between the damage effects and exposure doses were analyzed. 相似文献