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11.
Summary One hundred twenty-seven children with osteogenesis imperfecta (O.I.) were studied during the first 10 years of life. According to Sillence, 40 patients were assigned to type I, 39 to type III, and 48 to type IV O.I. Centiles for height, weight, and the annual number of fractures could be established for the different types of O.I. The development of the skeletal changes could be documented for the different forms of the disease. At birth, the skeletal changes were significantly more severe in type III than in type IV patients. During the first 10 years of life the number of fractures, extent of skeletal deformities, and growth retardation did not differ between types III and IV. Only fracture nonunion, dentinogenesis imperfecta, and congenital cardiac malformations were more frequent in type III than in type IV. Papillary calcifications of the kidney and kidney stones were diagnosed in 4 type III and 2 type IV patients. Hemihypertrophy of the body developed, in 2 type I patients. Although types III and IV patients suffered from severe short stature, serum insulin-like growth factor (IGF) I was in the normal range.  相似文献   
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衡阳市城区市售甲鱼中检测霍乱弧菌的采样调查   总被引:7,自引:3,他引:4  
目的了解衡阳市城区市售甲鱼中有无霍乱弧菌的感染。方法共采样55份,其中甲鱼肛门涂抹样36份,甲鱼表面粘液涂抹样19份。采用霍乱弧菌食物中毒的国家标准的检验方法进行检测。结果衡阳市市售甲鱼55份样本中有1份检测出O139血清型霍乱弧菌的感染。结论需采取相应的预防措施以防止霍乱弧菌引起的疫情。  相似文献   
14.
氧化亚氮联合利多卡因行无痛人工流产术280例临床分析   总被引:1,自引:0,他引:1  
目的: 探讨吸入 50%氧化亚氮 (N2O) 与 50%氧气 (O2 ) 的混合气体联合宫颈注射 2%利多卡因进行无痛人工流产术 (人流术) 的有效性和安全性。方法: 将人流术 580例分为A、B两组。其中A组 280例吸入 50%氧化亚氮 (N2O)与 50%氧气的混合气体联合宫颈注射 2%利多卡因进行无痛人流术, 称为联合组; B组 300例, 不用任何药物, 为对照组, 分析比较两组手术中镇痛效果, 宫口松弛情况, 手术出血量, 人流综合反应。结果: 联合组镇痛完全, 有效率达 97 5%。宫口完全松弛率 97 9%。两组比较有显著性差异 (P<0 05)。结论: 吸入氧化亚氮联合宫颈注射利多卡因进行无痛人流术, 镇痛效果确定, 人流时受术者意识处于朦胧状态, 安静, 无痛苦, 不良反应少, 苏醒快等。  相似文献   
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The objective of this study was to investigate the effect of arsenic trioxide (As(2)O(3)) on topoisomerase II levels using western blotting method on MDAH 2774 ovarian carcinoma cell culture. Experimental designs were established to determine the cytotoxic effects of As(2)O(3) on MDAH 2774 cells and the IC50 (fatal dose for the 50% of cells) value. Cytotoxicity experiments were carried out using various concentrations of As(2)O(3). The 2,3-bis[2-methyloxy-4-nitro-5-sulfophenyl]-2H-tetrazolium-5-carboxanilide (XTT) and trypan blue dye-exclusion tests were used to evaluate cytotoxicity. Topoisomerase II expressions were investigated using western blotting method with various concentrations of As(2)O(3). Densitometric analysis of topoisomerase 2 bands was carried out using Quantity One 1-D analysis software (Bio-Rad USA, Life Science Research, Hercules, CA). IC50 value of As(2)O(3) was found to be 5 x 10(-6) M for MDAH 2774 cells. When the bands were evaluated, it was observed that there was a decrease in topoisomerase II levels in MDAH 2774 cells with increasing concentrations of As(2)O(3). It was also observed by the densitometric analysis that topoisomerase II expression ratios of MDAH 2774 cells were decreased by approximately 50% at this concentration. Topoisomerase II levels were significantly decreased with the increasing concentrations of As(2)O(3). Inhibition of topoisomerase II enzyme was one of the antiproliferative influence mechanisms of As(2)O(3).  相似文献   
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A bacteriophage lytic for Escherichia coli O157:H7 was isolated from bovine manure. Following in-vivo selection, the phage acquired the capacity to persist in the circulatory system of mice for at least 38 days. When mice were infected experimentally with E. coli O157:H7 (10(7) CFU/mouse), simultaneous injection of the mice with phage (10(8) PFU/mouse) cleared E. coli O157:H7 from the mice within 48 h.  相似文献   
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四氧化三铁微粒与碘化油混悬液栓塞兔肾动脉的实验研究   总被引:1,自引:0,他引:1  
目的 探讨四氧化三铁(Fe3O4)微粒与碘化油(Lp)混悬液(suspension from magnetic microspheres with lipi odol, S Fe3O4 Lp)对兔肾动脉的栓塞和导向作用机制。方法 测定工业工艺制备粒径为 50~250μm 5 种规格的 Fe3O4微粒在Lp中的沉降时间、速度;实验组用粒径250μm的S Fe3O4 Lp对右肾动脉栓塞,对照组用Lp栓塞。两组于术后不同时间比较栓塞效果、观察血生化和病理学改变。结果 五种粒度的Fe3O4 微粒能在一定时间范围内悬浮于Lp中;栓塞效果实验组优于对照组;实验组栓塞部位Fe3O4 微粒与Lp存留存在明显正相关关系(P<0.005,r=0.76)。结论 粒径为250μm的S Fe3O4 Lp对兔肾动脉栓塞效果好,无明显毒副反应;栓塞过程中Fe3O4 微粒与Lp具有同步、同向性,是S Fe3O4 Lp发挥导向性栓塞的基础。  相似文献   
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Evidence from both experimental carcinogenesis and studies in human cirrhotic liver suggest that defective repair of the promutagenic DNA base lesion, O 6-methylguanine, is a factor in the multistep process of hepatocellular carcinogenesis. Ubiquitous environmental alkylating agents such as N-nitroso compounds can produce O 6-methylguanine in cellular DNA. Unrepaired, O 6-methylguanine can lead to the formation of G ? A transition mutations, a known mechanism of human oncogene activation and tumour suppressor gene inactivation. Combined treatment of rodents with an agent producing O 6-methylguanine in DNA, and an agent promoting cell proliferation, leads to development of hepatic nodules and hepatocellular carcinoma (HCC), cell division, hence DNA replication, being required for the propagation of tumorigenic mutation(s) in hepatocyte DNA. The paramount importance of O 6-methylguanine in hepatocellular carcinogenesis is indicated by the observation that transgenic mice engineered to have increased hepatic levels of repair enzyme O 6-methylguanine-DNA methyltransferase (MGMT) are significantly less prone to hepatocellular carcinogenesis following alkylating agent treatment. Cirrhosis is a universal risk factor for development of human HCC, and a condition that is characterized by increased hepatocyte proliferation as a result of tissue regeneration. Levels of the human repairing enzyme for O 6-methylguanine were found to be significantly lower in cirrhotic liver than in normal tissue. In accord with findings from animal models, this suggested a mechanism in which persistence of O 6-methylguanine due to defective DNA repair by MGMT, together with increased hepatocyte proliferation, might lead to specific gene mutation(s) and hepatocellular carcinogenesis. Screening for the presence and persistence of O 6-methylguanine in human DNA presently involves formidable technical difficulty. Indications are that such limitations might be overcome by the use of an ultrasensitive method such as immuno-polymerase chain reaction (PCR). This approach should allow parallel measurement of DNA adduct and repair enzyme in routine liver biopsy samples. It might also enable investigation of O 6-methylguanine in human genes specifically associated with hepatocellular carcinogenesis. Given the wide variation in human MGMT levels observed between individuals, tissues, and cells, this technology should be adapted to permit the ultrasensitive localisation and measurement of adducts and repairing enzyme in liver biopsy tissue sections. Ability to ultrasensitively measure O 6-methylguanine, and its repair enzyme, should prove valuable in the risk assessment of cirrhotic patients for developing hepatocellular carcinoma. Received for publication on July 6, 1998; accepted on Aug. 12, 1998  相似文献   
19.
刺五加制剂对老年人恒定负荷下运动耐力的影响   总被引:7,自引:0,他引:7  
以13名50~57岁志愿者为试验对象,研究了刺五加制剂对人体运动能力的影响。结果表明服用刺五加制剂后,在450kg.m/min(75W)持速恒定功率负荷运动时呼吸商由0.96下降至0.88,使运动时脂肪供能增加27.2%;心率下降8.7%,每博摄氧量增加16.18%。结果均提示刺五加制剂能提高人体摄氧能力,节省肌糖元,从而发挥抗疲劳作用  相似文献   
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