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61.
62.
Immunologic studies were performed on 5 patients with pigeon breeders' disease. Intradermal injection of pigeon serum produced an immediate wheal-and-flare reaction within 15 minutes and a secondary Arthus-type reaction within 4 to 8 hours. Immunofluorescent studies of the secondary reaction site showed IgG, C3, and C4 in 2 patients. Patients' sera produced multiple precipitin bands with pigeon serum when reacted by double diffusion in gel. IgG antibody isolated from each of the patients' serum formed precipitating immune complexes that fixed large amounts of complement (C4) when added to fresh human serum. Peripheral blood lymphocytes from 4 of the 5 patients produced macrophage migration inhibitory factor (MIF) when challenged with dilute pigeon serum. These studies are the first to show complement fixing antibodies and macrophage MIF production by lymphocytes from patients with hypersensitivity lung disease and suggest that both humoral and cellular immunity may be important in the pathogenesis of these disorders.  相似文献   
63.
Malignancy in patients with constitutional chromosome abnormality is of interest not only because it permits insights into the relationship between chromosome abnormality and cancer, but also because it provides opportunities to address such questions as the clonality and evolution of tumors. We report Ph1-positive chronic myelogenous leukemia (CML) in a 50-year-old mosaic (45,X/46,XX) Turner syndrome patient whose leukemia was restricted to the monosomic cell line. Our extensive cytogenetic studies of this patient demonstrated that non-leukemic normal cells persisted in the marrow and were able to proliferate during a period of temporary suppression of the leukemic clone following aggressive treatment.  相似文献   
64.
We previously demonstrated the activity of the R fragment in the long terminal repeat of human T-cell leukemia virus type I for elevation of the level of gene expression. In this study, the fragment was deleted with BAL31 nuclease to determine its functional domain. Series of the shortened R fragments were linked to the simian virus 40 promoter unit, which regulated expression of a reporter gene. Examination with the R fragments deleted from the 5 and 3 ends showed that borders of the functional domain were mapped within nucleotide positions 458 to 473 for the 5 end and nucleotide positions 559 to 594 for the 3 end, respectively. Thus we conclude that a 136-base-pair fragment corresponding to the second half of the R region was sufficient to allow elevation of the level of gene expression.  相似文献   
65.
采用半固体一步单层琼脂培养法和单克隆荧光抗体技术分别观察重症肝炎外周血TL-CFU和mIL-2R,发现重症肝炎患者TL-CFU(104.4±32.6)及mIL-2R(35.6±8.6)较正常人明显降低。在培养体系中加胎肝细胞质液后,无论在重症肝炎组还是在正常组均不能明显地提高TL-CFU,说明胎肝细胞质液不含具生物佐的促TL-CFU因子。但对mIL-2R表达的影响,在重症肝炎组病人,只有在PHA存在条件下才能促进mIL-2R的表达,说明胎肝细胞质波含有某种(些)物质能协同PHA促进重症肝炎患者外周血淋巴细胞mIL-2R表达。  相似文献   
66.
Chemically induced mutants of an I-Ak,d expressing antigen-presenting B-cell--B-lymphoma hybridoma have recently been generated by immunoselection in vitro and were found to possess alterations in some of their serologically and functionally defined I-Ak region dependent functions. In order to identify at the structural level the origin of the differences in serological and functional properties of these mutants, I-Ak molecules from several of these mutant hybridomas were compared biochemically to wild-type I-Ak polypeptides by two-dimensional gel electrophoresis and high-pressure liquid chromatographic tryptic peptide analyses. Two-dimensional gel electrophoresis indicated that no major structural alterations, resulting in changes in mol. wt or charge, had occurred in the Ak alpha or Ak beta polypeptides from the mutant cells. Likewise, Ak alpha peptide maps of the mutants were indistinguishable from the normal Ak alpha peptide maps. However, two of the three mutants studied did exhibit one additional peptide in their Ak beta peptide maps. These results suggest that the major deficiencies in T-cell-activating functions of these mutants are a result of a limited alteration in the Ak beta polypeptide primary structure.  相似文献   
67.
目的:研究普乐可复(FK506)对难治性肾病综合征患者血清IL-2、sIL-2R的影响及其临床意义。方法:应用酶联免疫吸附法检测难治性肾病综合征患者经普乐可复治疗前后血清IL-2、sIL-2R水平变化,并监测患者24小时尿蛋白、血浆白蛋白、血脂的变化。结果:难治性肾病综合征患者经普乐可复治疗前血清IL-2、sIL-2R水平均显著高于正常对照组(P<0.05)。治疗后血清IL-2、sIL-2R水平较治疗前明显下降(P<0.05)。治疗前24小时尿蛋白水平显著高于正常对照组(P<0.01),血浆白蛋白显著低于正常对照组(P<0.01),血脂水平显著高于正常对照组(P<0.01);与治疗前比较,治疗后24小时尿蛋白水平显著下降(P<0.05),血浆白蛋白水平显著升高(P<0.01),血脂水平显著下降(P<0.05)。治疗后组与正常组比较,除IL-2外,余各项指标均无显著性差异(P>0.05)。结论:在难治性肾病综合征患者体内存在IL-2、sIL-2R的异常,普乐可复对其有明确的抑制作用,从而调节T细胞活性,有效降低24小时尿蛋白,提高血浆白蛋白含量,降血脂,缓解难治性肾病综合征的病情。  相似文献   
68.
Summary: Blends of high molecular weight poly(R‐3‐hydroxybutyrate) (PHB) ( = 352 000 g · mol?1), comprising of either low molecular weight poly(R‐3‐hydroxybutyrate) (D‐PHB) ( = 3 900 g · mol?1) or poly[(R‐3‐hydroxybutyrate)‐co‐(R‐3‐hydroxyvalerate)] (PHBV) ( = 238 000 g · mol?1) with 12 mol‐% hydroxyvalerate (HV) content as a second constituent, were investigated along with the thermal properties and morphologies. After isothermal crystallization, a lowering of the melting temperature of PHB can be observed with increasing content of the second component in the blends. This behavior points towards miscibility of the constituents both in the liquid and the solid state. Crystallization kinetics was studied under isothermal and non‐isothermal conditions. The overall kinetics of isothermal crystallization was analyzed in terms of the Avrami equation. Only one crystallization peak is observed in all cases for the PHB/D‐PHB and PHB/PHBV blends under the conditions studied. This demonstrates co‐crystallization of the constituents. The addition of D‐PHB or PHBV to PHB reduces the rate of crystallization of the blends compared to that of neat PHB. The corresponding activation energies of crystallization also decrease with an increasing concentration of the second constituent. Non‐isothermal crystallization, carried out with different cooling rates held constant, is discussed in terms of a quasi‐isothermal approach. The corresponding rate constants as functions of reciprocal undercooling show Arrhenius‐like behavior in a certain range of temperatures. At sufficiently high undercooling, the rate constants of crystallization for the isothermal process exceed those reflecting non‐isothermal conditions, whereas in the limit of low undercoolings, the rate constants become similar. Ring‐banded morphologies are observed when PHB is in excess. When the respective second component is the major component, fibrous textures of the spherulites develop.

Polarized micrograph of PHB/PHBV 90/10.  相似文献   

69.
The present study was designed to investigate the relationship between intra-and inter-individual differences in arousal level and performance on both critical flicker fusion frequency and figural reversal tasks. Forty male undergraduate Ss were used. Electrical skin conductance was used as the indicant of arousal level. For the intra-individual comparisons white noise was used to increase the Ss’arousal levels. Significant inverted U-shaped relationships were found between both flicker fusion thresholds and rates of figural reversal and skin conductance between individuals. A significant curvilinear relationship was found between rates of figural reversal and level of conductance within individuals. No significant curvilinear relationship was found between flicker fusion thresholds and level of conductance within individuals.  相似文献   
70.
白细胞介素-8研究进展   总被引:14,自引:0,他引:14  
白细胞介素-8(IL-8)在趋化性细胞因子家族中属于C-X-C亚家族,IL-8是一个多种细胞来源的趋化性细胞因子,而且不同类型的细胞对不同的诱导剂的反应也不相同,因为由不同的实验室从不同的来源得到该因子,所以对于IL-8的许多不同的描述术语,对于IL-8的生理生化特性,目前已基本清楚,对于IL-8基因表达的调节,现认为主要是在转录水平的调控,并且发现其基因5′-侧翼区的AP-1,NF-кB及NF-IL-6结合位点是调节IL-8启动子功能的主要顺式作用元件,IL-8基因的表达需要这些元件之间高度的协同以达到有效的转录,IL-8受体则是一个由59KDa和67KDa亚单位组成的二聚体糖蛋白,存在于多种类型的细胞上,甚至包括一些不表达IL-8的细胞,IL-8的生物学活性并不表现出种族的特异性,IL-8可激活中性粒细胞,对T-淋巴细胞有趋化性并能刺激嗜碱性粒细胞,内皮细胞IL-8基因的表达除了受化学因子的调节外还受力学因素的影响,流体切应力诱导内皮细胞表达IL-8,可能在急性炎症和动脉粥样硬化的发生,发展过程中具有重要作用。  相似文献   
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