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21.
kDNA sequence homology of Leishmania donovani isolates from three types of kala-azar foci in China were analyzed by using dot and Southern hybridization with biotin- and 32P-labelled probes. The results revealed kDNA sequence heterogeneity among Leishmania donovani isolates from the three kala-azar foci: sequence homology between isolates of hill and desert foci was higher than that between hill and plain foci isolates. The kDNA hybridization technique was also found to be specific and sensitive for direct identification of Leishmania in animal tissues. In a preliminary survey, kDNA hybridization of cutaneous tissue blots of 71 dogs from endemic regions showed a positive rate of 40.8%, and the rate of double positive cases (touch blot hybridization and bone marrow smear) reached 91.3%. The direct identification of Leishmania in tissues by kDNA hybridization seems to be a useful and convenient method for epidemiological study and clinical diagnosis, especially for species/strain characterization.  相似文献   
22.
从加强医疗病房的重危患餐巾选取因呼吸衰竭而给予呼吸机支持的患者40例,随机分为A组20例进行肠外营养(parenteral nutrition,PN)治疗,B组20例未行PN治疗。对通气/换气功能各指标进行分析,结果两组患者的呼吸频率、pH、PaO_2、PaCO_2及HCO_3~-无明显差异;A组氧分压与吸入气氧浓度比值轻度降低,而肺泡-动脉氧压差及肺内分流明显升高。提示PN中的脂肪乳和高糖可能是导致呼吸功能改变的重要因素。  相似文献   
23.
目的观察深圳宝安3~7岁健康幼儿血清糖、离子、非蛋白含氮类化合物表达水平。方法采用OLRPUSAU-640全自动生化仪及OLRPUS诊断试剂、东欧生物诊断试荆,检测316例体检健康幼儿血清中Ca^++、Mg^++、P^+++、GLU、BUN、Cr、UA的含量。结果①.1组与4组及2组与3、4组Ca^++组间方差分析,差异有统计学意义,P〈0.05。②.1组与2、3、4组Cr组间方差分析,差异有统计学意义P〈0.05。而Mg^++、P^+++、GLU、BUN、UA组间方差分析差异无统计学意义,P〉0.05。结论笔者证实了3~4岁健康幼儿与6~7岁健康幼儿及4~5岁健康幼儿与5~7岁健康幼儿血清Ca^++表达水平有差异。也证实了3~4岁健康幼儿与4~7健康幼儿Cr含量存在差异。由此可见,3~7岁健康幼儿建立自己的参考值是必要的。  相似文献   
24.
组织多肽特异性抗原在乳腺癌中的临床研究   总被引:16,自引:1,他引:15  
OBJECTIVE: To investigate the expression of serum tissue polypeptide-specific antigen (TPS) in breast cancer patients and its clinical value in such cases. METHODS: Altogether 160 subjects (90 patients with breast cancer, 40 with benign breast lesions, and 30 healthy subjects) were enrolled in this study. The serum TPS and CA153 levels were measured by ELISA in all the subjects. RESULTS: The levels and positivity rate of serum TPS and CA153 in breast cancer group were significantly higher than those in the normal subjects group and benign lesion group (P<0.01), and became even higher as the malignancy progressed. High serum TPS level was detected in the cancer patients in stage I. Serum TPS level was the most sensitive to bone metastasis of the malignancy, but its highest levels occurred in cases of lymphoid node metastasis (P<0.05). In patients who responded favorably to the treatment, serum TPS and CA153 levels were significantly reduced (P<0.05), but the reduction in TPS levels tended to be more obvious (P<0.05). CONCLUSION: Serum TPS can be used as a very useful and sensitive tumor marker in the diagnosis of breast cancer, especially in case of bone metastasis, and may be of great value in clinical decision-making and assessment of therapeutic effect.  相似文献   
25.
目的观察耳廓复合游离组织瓣连续法修复鼻翼缺损的疗效,以探讨鼻翼缺损的有效修复手段。方法耳廓复合游离组织瓣2次连续法修复鼻翼缺损7例,移植物面积0.5cm×0.7cm~0.8cm×1.2cm。结果7例耳廓复合游离组织瓣移植后全部成活。术后随访6~18个月,移植物无明显回缩,鼻外形满意。结论耳廓复合游离组织瓣连续移植修复鼻翼缺损,适合较严重鼻翼缺损,手术成功率高,术后鼻外形满意,双侧分次取材,耳廓外形双侧对称无畸形。  相似文献   
26.
Block-copoly(oxypropylene/oxyethylene/oxypropylene)s, with central-block lengths of 39 and 75 oxyethylene units and end-block lengths in the range 1 to 13 oxypropylene units, were investigated in their solid states by small-angle X-ray diffraction and low-frequency Raman spectroscopy, supplemented by differential scanning calorimetry. Low-frequency Raman transitions were assigned to longitudinal modes (LAM) of either unfolded or once-folded chains. The solid state comprised stacked monolayer lamellae in which the chains were usually tilted with respect to the lamellar end plane.  相似文献   
27.
本实验选用具有生育力成年雄性猕猴7只,在直视下行双侧HFMC输精管内注射,每侧剂量分别为30mg1只,60mg和100mg各3只;于注射后2.5年和3.5年分别处死动物,取睾丸组织进行光镜和电镜观察.结果发现:猕猴注射HFMC2.5年后,睾丸光镜大部分曲细精管生精上皮结构完整,排列整齐。仅见局部少数管腔生精上皮层数减少,上皮细胞轻度水样变性等病理改变。电镜下曲细精管内除支持细胞内脂褐素增多,轻度基底膜增厚和精母细胞内质网扩张外,各级生精细胞,支持细胞及细胞间连接复合体等超微结构未见明显异常。注射HFMC3.5年后猕猴的光镜、电镜结果与注射后2.5年结果相似,但局部改变较2.5年组轻。上述结果表明:猕猴输精管内注射一定剂量HFMC节育不会引起睾丸组织的严重病理改变。但是,由于注射HFMC后,HFMC释放H+及其对输精管的暂时阻塞,改变了精子生存的内环境,使睾丸出现局部轻度病理改变,随着HFMC逐渐溶解排出,睾丸功能相继恢复正常,配对产仔。为HFMC应用提供了安全性依据。  相似文献   
28.
为探讨细胞外间质主要成分透明质酸(HA)与层粘连蛋白(LN)在缺血性股骨头坏死(INFH)中的生理病理过程及临床价值,采用放射免疫分析法对45例不同病因的INFH患者进行了血清HA与LN的定量分析,并与30例正常人对照。结果显示,INFH患者血清HA含量极显著地高于对照组(t=3-29;P<0-01)。尤以激素性INFN增高最为显著(t=3-62;P<0-01)。INFH患者LN含量亦明显高于对照组(t=2-84;P<0-01)。同时,HA与LN含量增高与病程发展密切相关。故定量检测HA与LN可作为INFH早期诊断及判断预后的良好指标  相似文献   
29.
Prostate cancer is one of the leading causes of cancer-related deaths for men in the United States. Like other malignancies, prostate cancer is underscored by a variety of aberrant genetic alterations during its development. Although loss of heterozygosity or allelic loss is frequently identified among prostate cancers, few genes have been identified thus far as critical to the development of invasive prostate cancers. In this report, we used the recently developed technology, the "differential subtraction chain," to perform a genome-wide search for sequences that are deleted in an aggressive prostate cancer. Among the deleted sequences, we found that one sequence was deleted in >50% of prostate cancers we tested. We mapped this sequence to chromosome 4q25 by screening the Genebridge 4 hamster radiation panel with primers specific to this probe, and subsequently identify a 54-kb minimal common deletion region that contains the sequence encoding myopodin. Sequence analysis indicates that myopodin shares significant homology with synaptopodin, a protein closely associated with podocyte and neuron differentiation. Further study shows that frequent complete or partial deletions of the myopodin gene occurred among invasive prostate cancer cases (25 of 31 cases, or 80%). Statistical analysis indicates that deletion of myopodin is highly correlated with the invasiveness of prostate cancers, and thus may hold promise as an important prognostic marker for prostate cancers.  相似文献   
30.
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