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81.
Cuprous chloride and copper powder (in acid media) initiate the aqueous polymerization of certain vinyl monomers such as methyl methacrylate, ethyl methacrylate, methacrylic acid and styrene but it fails in case of acrylonitrile, methyl acrylate, and acrylic acid under identical conditions. Catalyst exponent of this initiator (in acid aqueous media) with respect to methyl methacrylate is 0.38. Quantitative determination of end-groups by dye techniques of the polymers obtained shows that about 2 hydroxyl end-groups per chain are present under acidic conditions in presence of slight traces of oxygen but in rigorous absence of oxygen, very little OH end-groups are found incorporated. The mechanism of initiation under different experimental condition is discussed.  相似文献   
82.
Considerable genetic evidence exit for ANCA-associated vasculitis and pathogenesis. HLA A and B alleles identified serologically from 84 ANCA-positive patients were compared with 101 controls. Further subtyping were done in the 27 "pauci-immune" vasculitis patients using the polymerase chain reaction based PCR-SSOP technique and compared with controls (67). The results revealed that HLA A1 (OR=4.00; p value 2.72E-05), B17 (OR=3.38; p value 0.0008) and HLA B40 (OR=2.74; p value 0.001) were significantly increased among ANCA-positive patients when compared with the controls. Further, the molecular subtypes A*0101 (OR=5.04; p value 0.0005), B*5801 (OR=4.47; p value 0.0002) and haplotype A*0101-B*5801 (OR=4.47; p value 0.0001) were significantly increased among the autoimmune patients. The study revealed that HLA A1, B17 and B40 alleles are associated in production of antineutrophil autoantibodies and A*0101-B*5801 haplotype is significantly associated with autoimmune diseases and they may be invariably involved in disease pathogenesis in India.  相似文献   
83.
The monoclonal antibody RAP-5 generated against a synthetic peptide corresponding to amino acid positions 10-17 of the ras p21 protein was used in an immunohistochemical study of the expression of ras in normal, benign, and malignant breast epithelium in man. The staining intensity and intracellular distribution of RAP-5 was similar in the three epithelial populations and extended to other tissue elements including myoepithelial cells, smooth muscle, myelin, capillary endothelium, and stromal fibroblasts, as well as sebaceous glands and sweat glands overlying the breast. These results suggest that RAP-5 recognises a normal cellular component, the expression of which is not more enhanced in hyperplastic or neoplastic conditions. The detection of mutant forms of p21 exclusively expressed in malignant tumours requires that alternative reagents be developed.  相似文献   
84.
The scenario of cholera that existed previously changed in 1992 and 1993 with the emergence of toxigenic Vibrio cholerae O139 in India. The genesis of the new serogroup formed the impetus to search for O139 phages in and around the country. A total of five newly isolated phages lytic to V. cholerae O139 strains were used for the development of this phage typing scheme. These phages differed from each other and also differed from the existing O1 phages in their lytic patterns, morphologies, restriction endonuclease digestion profiles, and immunological criteria. With this scheme, 500 V. cholerae O139 strains were evaluated for their phage types, and almost all strains were found to be typeable. The strains clustered into 10 different phage types, of which type 1 (38.2%) was the dominant type, followed by type 2 (22.4%) and type 3 (18%). Additionally, a comparative study of phage types in 1993 and 1994 versus those from 1996 to 1998 for O139 strains showed a higher percentage of phage type 1 (40.5%), followed by type 3 (18.8%) during the period between 1993 and 1994, whereas phage type 2 (32. 1%) was the next major type during the period from 1996 to 1998. This scheme comprising five newly isolated phages would be another useful tool in the study of the epidemiology of cholera caused by V. cholerae O139.  相似文献   
85.
Details of a simple radioaerosol generator and delivery system are presented. Aerosol streams of 99mTc-DTPA solution of different distributions were produced. The most useful distribution had an activity median aerodynamic diameter (AMAD) of 0.9 m with a geometric standard deviation of 1.5. This distribution also had more than 96% of aerosol particles with aerodynamic diameter <2 m. The system has been used for patient lung ventilation studies. The aerosol breathing-in period to achieve a satisfactory count rate was 1.8±0.38 min. The radioaerosol images were excellent and comparable to those obtained with 81mKr gas.  相似文献   
86.
Journal of Public Health - Depression is a major morbidity and the most common mental disorder among the medical students in medical schools globally. Undergraduate students suffer stress more due...  相似文献   
87.
人体子宫内膜血管内皮生长因子的研究   总被引:1,自引:0,他引:1  
目的 :对人体子宫内膜增殖期 (n =3)、分泌期 (n =6 )和增生过长 (n =6 )标本 ,进行VEGF的免疫定位和半定量测定 ,了解雌激素对子宫内膜VEGF的影响。方法 :研究组用免疫组织化学方法 ,对照组用无关的免疫球蛋白代替第一及第二抗体 ,用辅助视频图像分析系统进行计算。结果 :增殖期VEGF在腺体 (P <0 .0 0 1)和间质 (P <0 .0 1)的浓度 ,明显高于分泌期和子宫内膜增生过长 ,总的看来 ,腺体的VEGF高于间质。结论 :雌激素提高子宫内膜的VEGF的含量 ,并与增殖晚期新的血管形成和血管通透性增加有关。此外 ,子宫内膜增生过长的腺体VEGF并不升高 ,提示人体子宫内膜的腺体生长和血管生成调节是不同的。  相似文献   
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OBJECTIVE AND DESIGN: Asthma is an inflammatory disease of the airways and the current focus in managing asthma is the control of inflammation. In this study, we attempted to investigate the anti-asthmatic potential of a plant derived natural compound, luteolin. MATERIAL: We used a murine model of airway hyperreactivity, which mimicked some of the characteristic features of asthma. Male BALB/c mice (8-9 weeks) were used for this study. TREATMENT: Mice (n = 6) were sensitized by intraperitoneal (i. p.) injection of 10 mg of ovalbumin (OVA) on days 0, 7 and 14 followed by aerosol inhalation (5% OVA) treatments daily beginning from day 19 to day 23. To study its preventive effect, luteolin (0.1, 1.0, and 10 mg/kg body weight; daily) was administered orally during the entire period (0 to 23 day) of sensitization. To study its curative effect, mice were first sensitized and then luteolin (1.0 mg/kg body weight daily) was given orally from day 26 to 32. The airway hyperreactivity, immunoglobulin E (IgE) in the sera, and cytokines (IFN-gamma, IL-4 and IL-5) in the bronchoalveolar lavage fluid (BALF) were measured. RESULTS: Both during sensitization and after sensitization, luteolin, at a dose of 0.1 mg/kg body weight, significantly modulated OVA-induced airway bronchoconstriction and bronchial hyperreactivity (p < 0.05). Luteolin also reduced OVA-specific IgE levels in the sera, increased interferon gamma (IFN-gamma) levels and decreased the interleukin-4 (IL-4) and interleukin-5 (IL-5) levels in the BALF. CONCLUSION: Our study showed that luteolin treatment during and after sensitization significantly attenuated the asthmatic features in experimental mice. Therefore, luteolin could be used either as a lead molecule to identify an effective antiasthma therapy or as a means to identify novel anti-asthma targets.  相似文献   
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