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101.
Conventionally a confidence interval (CI) for the standardized mortality ratio is set using the conservative CI for a Poisson expectation, μ. Employing the mid-P argument we present alternative CIs that are shorter than the conventional ones. The mid-P intervals do not guarantee the nominal confidence level, but the true coverage probability is only lower than the nominal level for a few short ranges of μ. The implications for mid-P confidence intervals of various proposed definitions of two-sided tests for discrete data are discussed.  相似文献   
102.
The technique of Enzyme linked immuno-electrophoresis (ELIEP) was established to detect the specific antibody against tubercle bacilli. The results of 730 cases showed that the sensitivity of this method is 97.33%, and the specificity, 97.5%. Thus this method is more sensitive than the ELISA methods which had bean published. The manipulation of ELIEP is simple, convenient, and fast, reagent stable. This method may be used in diagnosis of tuberculosis with reliability and efficiency.  相似文献   
103.
采用平阳霉素作为诱变剂,对28例喉癌患者和23例正常人做外周血淋巴细胞染色体对诱变剂敏感性研究,结果显示喉癌患者的染色体总畸变率、每细胞染色单体断裂率(b/c值)和细胞畸变率分别为1.98%±0.05%,0.57%±0.35%和42.8%±12%。正常人则分别为0.94%±0.04%,0.28%±0.12%和27%±12%。经统计学处理,喉癌患者组与正常人组的差异有高度显著性。并结合实验结果探讨了染色体对致突变剂的敏感性与患喉癌风险的关系。  相似文献   
104.
Immunoscintigraphy with radiolabelled monoclonal antibodies is widely used to detect solid tumours, but only a few trials have been carried out concerning the specific in vivo localization of an inflammatory process. The purpose of this study was to investigate the detectability of tuberculous foci utilizing this method with radiolabelled bacillus Calmette-Guérin (BCG)-specific F(ab')2 in rabbits. All of the tuberculous lesions (n = 8) were clearly visualized on serial scintigraphy for up to 48 h after injection of the antibody. Immunohistochemical and Ziel-Neelson staining of the tuberculous lesions confirmed the presence of the tuberculous antigens and bacilli. It failed to demonstrate any sustained retention of the BCG-specific antibody fragment in the control group with syphilitic orchitis (n = 2). Therefore, the specific in vivo localization of tuberculosis is feasible by immunoscintigraphy.  相似文献   
105.
The sensitivity of alpha-naphthyl acetate esterase (ANAE) activity of human, bovine, canine, and murine leukocytes to low (42 micrograms/ml incubation mixture) and high (1.5 mg/ml incubation mixture) concentrations of sodium fluoride (NaF) was compared. The ANAE activity of bovine and canine monocytes was only slightly inhibited by the low concentration of NaF, whereas that of murine peritoneal macrophages was moderately inhibited and that of human monocytes was completely inhibited. Human and canine monocytic ANAE was completely inhibited by the high concentration of NaF, whereas the ANAE activity in 1% of bovine monocytes and murine peritoneal macrophages was not inhibited. The ANAE activity of human and murine lymphocytes in nonenriched venous blood samples showed no or negligible NaF sensitivity to the low concentration of NaF, whereas bovine lymphocytic ANAE showed slight and canine lymphocytic ANAE moderate NaF sensitivity. The ANAE of murine T-lymphoma L5178Y cells was resistant to the low concentration of NaF, but the ANAE of both murine T-lymphoma L5178Y cells and murine lymphocytes was completely inhibited by the high concentration of NaF. Human, bovine, and canine lymphocytic ANAE showed marked NaF sensitivity toward the high concentration of NaF, showing 73%, 86%, and 93% inhibition, respectively. The neutrophils in murine venous blood and ascites were positive for ANAE activity, which was only slightly inhibited by the low concentration of NaF but completely inhibited by the high concentration. Results of this investigation demonstrate that the ANAE of leukocytes of various species show remarkable differences in its sensitivity to low and high concentrations of NaF, indicating that appropriate concentrations of NaF are required for distinguishing the ANAE of lymphocytes and monocytes of different species.  相似文献   
106.
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   
107.
目的:观察体外循环(CPB)对10例瓣膜置换术病人全血细胞胰岛素受体和红细胞ATP含量的影响。方法:利用放射配体结合试验,测定全血细胞胰岛素受体密度和亲和力;用高效液相色谱法测定红细胞ATP含量,同时监测血糖和胰岛素浓度。结果:转流30分钟,血细胞高亲和胰岛素受体(R1)密度明显增加(P<0.01),亲和力(K1)明显降低(P<0.01),低亲和胰岛素受体(R2)密度也明显增加(P<0.01),但亲和力(K2)变化不大(P>0.05);停机30分钟,上述变化有所恢复,但未到转流前的水平。转流30分钟红细胞ATP含量明显降低(P<0.01),并持续到停机后30分钟,同时伴随血糖明显升高(P<0.01),胰岛素/血糖比值明显降低(P<0.01)。结论:CPB可致血细胞胰岛素受体密度增加而亲和力下降,以及红细胞ATP含量下降。  相似文献   
108.
Adenophora polysaccharides (AP), is an active principle extracted from the root of Adenophorae Potaninii Korsh originated in Gansu Province and isolated with boiling water(1). AP is isolated and purified from the crude drug by DEAE-cellulose and Sephadex G-200 column, with a white powder and mean molecular weight of 8.3 × 104 , and [α]D20of AP is 68(1). AP is only composed of glucose judging from the analysis of it with patina chromatography (PC) and gas chromatography-mass spectrometer (GC-MS) methods.The methylation analysis showed that AP is composed of (1→6) linked glucose residues. The measure of nuclear magnetic resonance imaging (NMR) 1H NMR and 14C NMR techniques further proved that AP is α(l→6) linked by Dglucose. The structure of AP is as follows: -[→6]α-D-Glu(1-)n→ (2).  相似文献   
109.
杨元  肖翠英  张思仲  张思孝  黄明孔  林立 《四川医学》2004,25(11):1166-1168
目的 探讨Y染色体无精症因子C区(azoospermia factor C,AZFe)无精症缺失基因(deleted-in-azoospermia,DAZ)家族基因拷贝缺失与中国男性原发不育之间的关系。方法 运用多重PCR与PCR-RFLP检测技术,对210例已生育男性、216例原发无精症与189例严重少精症患者Y染色体AzFc区域DAZ基因家族的基因拷贝数进行分析。结果 在所有已生育男性中未检出DAZ基因拷贝的完全或部分缺失,而在原发无精症与严重少精症患者中DAZ基因拷贝完全缺失率分别为8.8%和12.2%,DAZ1/DAZ2共缺失率分别为8.3%和5.3%。结论 在中国男性原发无精症与严重少精症患者中存在较高频率的DAZ基因拷贝缺失现象,提示Y染色体AZFc区域DAZ基因家族基因拷贝的完全与部分缺失是中国男性原发不育的遗传高风险因子。  相似文献   
110.
Primary megaureter presents a spectrum of findings ranging from mild, clinically unimportant, stable ureterectasis to severe, progressive obstructive hydroureteronephrosis. We report a patient with a double uterus and ipsilateral renal dystrophy. A previous imaging study had revealed a double uterus and obstructed left hemivagina, into which a single vaginal ectopic ureter inserted. On follow-up intravenous urography 8 years later, the left kidney was non-functioning, and there was segmental dilation of the distal right ureter. Transvaginal sonography with real-time scanning and Doppler were useful in exploring the morphological and functional status of this dilated distal ureter.  相似文献   
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