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51.
Retrorenal colon: implications for percutaneous diskectomy 总被引:1,自引:0,他引:1
It has been recommended that computed tomography (CT) with the patient prone be performed in every patient undergoing percutaneous diskectomy; this would enable detection of a retrorenal location of the colon, which could interfere with the percutaneous procedure. In this evaluation of 346 prone CT studies, only one patient (0.29%) was found to have retrorenal or retropsoas bowel that would have been perforated at diskectomy. Because of this extremely low prevalence, the performance of prone CT in every patient undergoing percutaneous lumbar diskectomy is not believed to be necessary. 相似文献
52.
法莫替丁冲剂在健康人中的生物利用度及药动学研究 总被引:1,自引:0,他引:1
本实验采用反相高效液相色谱法,比较了10名健康志愿者单剂量口服法莫替丁冲剂及等剂量片剂的生物利用度。结果表明:二种剂型的Tmax,Cmax,AUC均无显著性差异(P〉0.05)。冲剂相对于与片剂的相对生物利用度F=101.90。 相似文献
53.
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
54.
阔筋膜皮瓣移植修复手前臂巨大创面 总被引:4,自引:0,他引:4
报道采用吻合血管的阔筋膜皮瓣移植,修复手、前臂巨大创面11例,均获成功,其优点:①阔筋膜长而坚韧,内面光滑,覆盖关节、骨、肌腱粘连轻,尤其利于肌腱滑动,是修复手、前臂的最佳皮瓣。②皮肤与肌腱同时缺损时,利用阔筋膜修复肌腰,一期完成肌腱及皮肤的修复。③股外侧皮神经长而粗,分支多,适合手部感觉修复。④供区隐蔽,皮下组织簿,血运丰富,供皮及阔筋膜面积大。 相似文献
55.
慢性乙型肝炎表面抗原携带者前S1基因的高度异质性 总被引:1,自引:0,他引:1
应用半巢式聚合酶链式反应(PCR)从一例慢性HBsAg携带者血清中扩增出HBV前S1基因,将其克隆于噬菌体M13mp19中进行序列分析。结果发现:与同源性最好的HBVadr野生林相比,所测的10个克隆均有替代和插入突变,9个克隆有缺失突变,10个克隆的核苷酸变异率为5.0%-17.0%,氨基酸的变异率为13.0-60.0%;10个克隆之间的核苷酸变异率为2.3%-24.3%,氨基酸的变异率为14. 相似文献
56.
采用毛细管流交仪测定了PBT/PC共混物的表观粘度、剪切应力,观察了不同共混物组成和不同温度下共混物的流变行为,并借助扫描电镜对共混物和微观形态结构进行分析。结果表明:PBT/PC熔体共混物的流变行为接近假塑性流体.温度对共混物的流变行为影响很大,共混物的熔体粘度在PBT/PC为90/10和60/40时呈双极值.共混物为两相结构,PC含量为4-50%时呈两互锁结构。 相似文献
57.
Teresa S. Priebe Edward N. Atkinson Bih-Fang Pan J. Arly Nelson 《Cancer chemotherapy and pharmacology》1992,29(6):485-489
Summary PANC02 is a ductal adenocarcinoma of the pancreas that is resistant to every known class of clinically active antitumor agent. To study the mechanism(s) underlying the intrinsic drug resistance of this tumor, a mammary adenocarcinoma (CA-755) that also grows in C57/BL mice and is known to be drugsensitive was used for comparison. PANC02 resistance and CA-755 sensitivity to several antitumor agents and to X-ray therapy was confirmed in mice, and PANC02 also demonstrated relative resistance in tissue culture. Relative to Chinese hamster ovary (CHO) and CA-755 cells, PANC02 did not appear to show a higher rate of mutation to drug resistance in culture as based on the 6-thioguanine resistance marker. Although P-glycoprotein characteristic of the multidrug resistance (MDR) phenomenon could be demonstrated at the mRNA level using a sensitive RNAse protection assay, the level of expression found was several orders of magnitude lower than that observed in phenotypic MDR cell lines. Furthermore, quinidine failed to increase the sensitivity of PANC02 cells to Adriamycin under conditions that clearly potentiated the toxicity of the drug to a CHO cell line exhibiting classic MDR traits. The heterogeneity in the distribution of drugs was inferred as being significantly greater in PANC02 versus CA-755 cells in vivo as based on measurements of within-animal, within-tumor variance in the distribution of the marker compounds inulin and antipyrine. Although it may not be the only mechanism involved, this greater intratumor heterogeneity in drug distribution could theoretically play a major role in the intrinsic drug resistance of PANC02 in vivo.Supported by grant CH-458 from the American Cancer Society, by grant CA-28034 from the National Cancer Institute, and in part by Cancer Center Core Support grant, NIH-NCI-CA-16672. Animals were maintained in facilities approved by the American Association for Accreditation of Laboratory Animal Care and in accordance with current United States Department of Agriculture, Department of Health and Human Services, and National Institutes of Health regulations and standards 相似文献
58.
Sera from 130 first trimester pregnant women were tested for their serum antibody level against a naturally occurring serum antigen purified from non-pregnancy sera. IgG and IgM antibody level was measured using enzyme linked immunosorbant assay. Results indicate that patients with multiple abortion (n=26) have significantly (p=0.0029) lower level of IgG antibody and significantly (p=0.0001) higher level of IgM antibodies; against the serum antigen as compared to the patients with successful pregnancies with no history of miscarriage (n=63). Western blot analysis identified the scrum antigen recognized by the IgM antibody as a 24 kDa molecular mass component. These IgG and IgM antibodies may play an important role in the outcome of pregnancy. 相似文献
59.
60.
探讨荧光原位杂交法(FISH)对母血中胎儿有核红细胞(NRBC)进行无创性产前诊断的可行性。20例孕龄15-20周的孕妇外周血经不连续密度梯度离心、制片、显微镜下识别并共计数NRBC及定位,然后行Y染色体的FISH检测。结果发现10例孕男性胎儿的孕妇外周血细胞涂片中每例均有阳性杂交信号出现;阳性率为60%(24/40)。10例孕女性胎儿的孕妇外周血细胞涂片中1例出现阳性杂交信号;阴性率为95%(38/40),假阳性率仅为5%(2/40)。结果提示FISH法对于用母血中分离到的胎儿细胞进行染色体异常的无创性产前遗传学检查具有重要意义。 相似文献