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31.
Polyclonal antibodies directed against human recombinant basic fibroblast growth factor were used in immunohistochemical studies to localize this growth factor in normal and wounded rat skeletal muscles. According to the intensity of the stain, three main classes of fibers could be identified: the strongly, moderately, and weakly stained fibers. Basic fibroblast growth factor immunoreactivity was found mainly in the extracellular matrix, primarily in the endomysium, which includes the heparin-containing basal lamina, and also in the capillary basal membrane of both normal and wounded muscles; however, the signal intensity was much stronger in normal muscles. The distribution of basic fibroblast growth factor in wounded muscles became markedly heterogeneous and sparse. After 4 hours of ischemia, about 40% of skeletal muscle fibers lost their basic fibroblast growth factor immuno-reactivity. Muscles which underwent 4 hours of ischemia and 24 hours of reperfusion had only a diminished basic fibroblast growth factor immunoreactivity. The pathologic results supported the concept of destroyed cell connection and fiber necrosis in ischemic and reperfused muscles. Potential mechanisms involved in this reduced concentration of basic fibroblast growth factor in wounded muscles may include oxygen free radical activation, a generalized effect of the inflammatory response, and reduced secretion of endogenous basic fibroblast growth factor. These results are only partially compatible with the established mitogenic role of this growth factor and suggest that a reduction of endogenous fibroblast growth factor may partly contribute to a delay in wound healing.  相似文献   
32.
Soluble lens crystallins from 6-10-week-old, galactose-fed, male Sprague-Dawley rats were analyzed by two-dimensional polyacrylamide gel electrophoresis at each of the five Sippel stages of cataractogenesis. Electrophoretograms were compared with similarly analyzed crystallins from comparably aged, chow-fed controls. Polypeptides were assigned to crystallin families and subfamilies on the basis of chromatographic fractionations with Sephadex G-200, superfine. Staining intensities of polypeptides from control lenses remained essentially unchanged throughout the experimental period, while those of the polypeptides from cataractous lenses showed non-uniform changes. Staining of the genomic gamma-crystallins increases up to at least stage 3; by stage 4, staining of gamma-chains, with perhaps those of gamma 5 and gamma 6 excepted, diminishes and in the total cataract, staining of all chains is further reduced. With possibly the addition of one chain, the total number of postsynthetically modified gamma-crystallins in cataractous lenses does not exceed that in the comparably aged normal lens. The genomic alpha- and beta-crystallin polypeptides are sustained close to normal levels up to stages 3 or 2, respectively, after which their gradually falling levels are accompanied by the generation of new species or elevated levels of existing post-translational species. An exception to this behavior is the rapid and total loss of beta B1a, a genomic subunit implicated in the aggregation of beta H-crystallins. Charge heterogeneity and variable pI displayed by beta B1a and other highly cationic beta- and gamma-crystallin polypeptides can be induced during isoelectric focusing and may be due to thiol group oxidation.  相似文献   
33.
本文采用中和试验、沉降反应和解离试验对135例已知血型人精液中ABH血型物质的分泌强度进行了检验,并将其分为强、中、弱三型。这对区别个人血型物质含量及性犯罪的法医学鉴定均有重要意义。并证明了AB型人精液中A、B血型物质含量不均等现象,并且绝大多数人B型物质高于A型物质。  相似文献   
34.
分析了1984~1993年期间47例经治的急性视神经炎患者。治疗应用地塞米松10mg、青霉素480万u静脉点滴7天,随后减量。结果治愈35例(74.47%),好转6例(12.76%),无效2例(4.26%),转院及自动出院各2例。47例中11例治疗效果不好者行筛窦开放术后,视力逐渐恢复正常,显示筛窦开放术有其临床实用价值。  相似文献   
35.
目的寻求一种简单有效的内眦赘皮矫治方法.方法采用改良V-W成形,即赘皮皮肤的V-W推进改形,加上新内眦点与鼻根外侧的筋膜或骨膜固定、松解皮下粘连、修整错构的眼轮匝肌等,全面治疗内眦赘皮.大部分病例与重睑术同期进行.结果1999年至今矫治明显的内眦赘皮67例,术后效果满意.术后1个月有5例出现内眦部切口增生发红,3-4月逐渐软化消退.所有病例随访1个月到1年,均获得满意疗效.结论改良V-W成形手术切口设计简单明了,术后内眦形态良好,不易复发,瘢痕不显,是矫正内眦赘皮较理想的方法.  相似文献   
36.
白细胞介素-4和γ-干扰素基因联合治疗胶质瘤   总被引:1,自引:1,他引:0  
目的 探讨逆转录病毒载体介导的白细胞介素(IL)-4和γ-干扰素(IFN)基因联合治疗胶质瘤的作用。方法构建携带IL-4或IFN-γ基因的逆转录病毒载体,将其导入逆转录病毒包装细胞;将携带IL-4和IFN-γ基因的逆转录病毒包装细胞分别或联合注射到脑内荷瘤大鼠的肿瘤组织中,观察其治疗作用。结果成功获得携带治疗基因的逆转录病毒包装细胞PA317IFN-γ和PA317IL-4,所产病毒滴度分别为2x10^6cfu/ml和2.5x10^6cfu/ml。包装细胞瘤内注射能够诱导大鼠产生抗肿瘤免疫反应,杀伤肿瘤细胞,联合应用具有协同治疗作用。结论携带IL-4或IFN-γ基因的逆转录病毒包装细胞瘤内注射是一种有效的胶质瘤基因治疗方法,两者联合应用具有协同治疗作用。  相似文献   
37.
38.
采用大剂量甲基强的松龙治疗脱髓鞘脑病患者15例。在治疗过程中,积极预防应激性溃疡,加强呼吸道及人工冬眠护理。经5次治疗,14例症状明显改善。  相似文献   
39.
Fu SL  Ma ZW  Yin L  Iannotti C  Lu PH  Xu XM 《Neuroscience》2005,135(3):851-862
To determine whether neural precursor cells have region-specific growth properties, we compared the proliferation, mitogenicity, and differentiation of these cells isolated from the embryonic day 16 rat forebrain and spinal cord. Neural precursor cells isolated from both regions were cultured in growth medium supplemented with epidermal growth factor, basic fibroblast growth factor, or epidermal growth factor+basic fibroblast growth factor. Under all three conditions, both neural precursor cell populations proliferated for multiple passages. While spinal cord-derived neural precursor cells proliferated moderately faster in epidermal growth factor-enriched growth medium, brain-derived cells proliferated much faster in basic fibroblast growth factor-enriched growth medium. When exposed to both epidermal growth factor and basic fibroblast growth factor, the two neural precursor cell populations expanded and proliferated more rapidly than when exposed to a single factor, with brain-derived neural precursor cells expanding significantly faster than spinal cord-derived ones (P<0.0001). Differentiation studies showed that both neural precursor cell populations were multi-potent giving rise to neurons, astrocytes, and oligodendrocytes. However, neuronal differentiation from brain-derived neural precursor cells was greater than spinal cord-derived ones (11.95+/-5.00% vs 1.92+/-1.13%; passage 2). Further, the two neural precursor cell populations differentiated into a similar percentage of oligodendrocytes (brain: 8.66+/-5.85%; spinal cord: 7.69+/-3.91%; passage 2). Immunofluorescence and Western blot studies showed that neural precursor cells derived from both regions expressed receptors for basic fibroblast growth factor and epidermal growth factor. However, brain-derived neural precursor cells expressed higher levels of the two receptors than spinal cord-derived ones in growth medium containing epidermal growth factor+basic fibroblast growth factor. Thus, our results showed that neural precursor cells isolated from the two regions of the CNS have distinct properties and growth requirements. Identifying phenotypic differences between these neural precursor cell populations and their growth requirements should provide new insights into the development of cell therapies for region-specific neurological degenerative diseases.  相似文献   
40.
On December 31, 2001, 2486 patients with terminal renal failure received dialysis treatment in Croatia. Only one third of the patients are registered on the national waiting list for cadaveric kidney transplant. In most of the others, transplantation is impossible because of comorbidity. This is mainly due to the steadily growing age of the dialytic population and therefore a higher incidence of cardiovascular disease and diabetes. Still, evaluation of the potential recipients of cadaveric kidney transplant, registered on the waiting list, often reveals contraindications for transplantation. The aim of this study was to determine the incidence and type of contraindications in transplant candidates, found during immediate preoperative evaluation. Analysis of these data should help in determining how contraindications can be early detected and prevented. Before registering onto the national waiting list transplant candidates need to be thoroughly investigated including detailed history, physical examination, routine diagnostic procedures and additional examinations, if needed, to exclude or evaluate the possibly existing contraindications for transplantation. During the period from January 1997 until June 2002, 145 potential recipients from the national waiting list were referred to the Rijeka University Hospital Center and evaluated for kidney transplantation. Eighty-eight patients underwent transplantation. Preoperative evaluation revealed contraindications for transplantation in 52 (35.9%) candidates. Twenty-two (15.2%) patients had a positive cross-match with donor lymphocytes, 6 (4.1%) patients refused transplantation, and in 24 (16.6%) patients serious comorbidity was the reason for not being accepted for transplantation and for their withdrawal from the national waiting list. Comorbidity was mainly due to cardiovascular disease (12 patients--8.3%) and infection (8 patients--5.5%). These data show a high incidence of contraindications found during the immediate preoperative evaluation of potential kidney recipients. It was the case in more than one third of patients. During the evaluation of potential candidates for kidney transplantation special attention should be addressed to the presence of cardiovascular morbidity and infection. Peripheral vascular occlusive disease, cardiac status and/or cerebrovascular disease should be evaluated. Measures used to treat or reduce the development of complications include an optimal control of blood pressure, serum phosphate, hyperparathyroidism, dyslipidemia, and renal anemia. The sites of infection must be treated and eradicated, because immunosuppressive treatment is a threat to the transplant recipient's life. The second most common cause of refusal of potential candidates was a positive cross-match with donor lymphocytes. Sensitization to human leukocyte antigens can be prevented by the avoiding of blood transfusions and use of erythopoietin in treating renal anemia. To minimize the morbidity and mortality, the potential kidney recipients should undergo rigorous selection and thorough evaluation before including them into the waiting list for kidney transplantation. Afterwards, regular examinations are obligatory to reveal contraindications, proceed to medical interventions and treat concomitant diseases in time, which can influence the patient's survival. In case that contraindications for transplantation arise, the patient must be temporarily or definitely removed from the waiting list.  相似文献   
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