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In vitro IgE secretion by atopic and normal peripheral-blood lymphocytes was examined in culture with pokeweed mitogen or Staphylococcus aureus strain Cowan-I (StaCw) or without mitogen. IgE secreted in culture supernatants was measured with double antibody radioimmunoassay. Enumeration of IgE-secreting cells was made by a protein-A plaque assay. IgE was detected in increasing quantities in supernatants of cultured lymphocytes without mitogen up to the 12th day. IgE-plaque-forming cells were formed by the lymphocytes in large numbers on days 4–7 in cultures with mitogen. These results suggest that not only mitogen-independent but also mitogen-dependent subpopulations may exist in the IgE-secreting cells.  相似文献   
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Objective To study the constituents in the whole plant of Boschniakia rossica. Methods The constituents were separated and purified with chromatographic methods. Their structures were elucidated by spectroscopic methods (1D, 2D NMR, UV, IR, and HRESI-TOF-MS) and chemical analyses. Results One new phenylpropanol glycoside (1) and its five known analogues were obtained from B. rossica. They were identified as trans-p-coumaryl- (2′-O-β-D-glucopyranosyl)-β-D-glucopyranoside (1), salidroside I (2), rossicasin A (3), trans-p-coumaryl alcohol 1-O-β-glucopyranosyl(1→4)-α-rhamnopyranosyl(1→3)-β-glucopyranoside (4), salidroside (5), and acetoside (6). Conclusion Among the known compounds, compound 2 is firstly isolated from the plants in genus Boschniakia C. A. Mey. ex Bongard. Meanwhile, the 13C-NMR data of 9 and 4′ positions in compound 4 are corrected.  相似文献   
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Lack of linkage between atopy and locus 11q13   总被引:4,自引:0,他引:4  
Atopy as defined in terms of IgE responsiveness was reported to be controlled by a single gene in British families, and this concept was further supported by a significant linkage between atopy and restriction fragment length polymorphism (RFLP) detected by a DNA probe specific to chromosome 11q13. To confirm this observation in a Japanese population, segregation and linkage analyses were done in four large families. Although segregation patterns of atopy were in agreement with the pattern of autosomal dominant inheritance, there was no significant linkage between atopy and locus 11q13. Alterations in the definitions of atopy did not affect the results. These findings suggested the presence of heterogeneity in genetic elements of atopy, even though atopy may be determined mainly by a single dominant gene.  相似文献   
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目的 研究电离辐射诱发人骨肉瘤肿瘤细胞DNA双链断裂与辐射损伤修复效应,观察辐射损伤、损伤修复效应敏感性之间的关系。方法 选用强制均匀电场电泳,分别测定经不同的剂量X射线照射和相同剂量照射后培养不同时间,人骨肉瘤Rho0和143.B肿瘤细胞株DNA双链断裂。结果 (1)X射线诱发人骨肉瘤瘤细胞的DNA双链辐射剂量呈线性正比关系;(2)培养后的人骨肉瘤肿瘤细胞对射诱发的DNA双链断裂具有一定修复能力  相似文献   
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Objectives: To assess the efficacy, safety, and tolerability of fesoterodine 4 and 8 mg once daily (QD) compared with placebo in Asian subjects with overactive bladder (OAB) after 12 weeks of treatment. Methods: This phase II, dose‐finding study consisted of a 2‐week placebo run‐in period followed by a 12‐week, randomized, double‐blind, placebo‐controlled, treatment period. Eligible subjects were aged ≥20 years with ≥8 micturitions per 24 h and ≥1 urgency urinary incontinence (UUI) episodes per 24 h reported in a 3‐day diary. The subjects were randomized to receive placebo, fesoterodine 4 mg, or fesoterodine 8 mg QD for 12 weeks. Results: Of 1232 subjects who entered the placebo run‐in period, 951 received double‐blind treatment. The mean number of UUI episodes per 24 h at baseline was 2.2 among the three treatment groups. The two fesoterodine groups showed statistically significant decreases from baseline in the mean number of UUI episodes per 24 h at week 12 (primary endpoint) compared with placebo. Most all‐causality adverse events (e.g. dry mouth and constipation) were mild or moderate. The percentage of subjects with severe adverse events was low and similar among the treatment groups (placebo, 1.3%; fesoterodine 4 mg, 1.9%; fesoterodine 8 mg, 1.0%). Conclusion: Fesoterodine 4 and 8 mg QD were significantly better than placebo in improving OAB symptoms. Overall, the two fesoterodine dosing regimens were well tolerated. These results suggest that fesoterodine 4 and 8 mg QD are effective and well‐tolerated treatments for OAB in Asian subjects.  相似文献   
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