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101.
经承学  谢湘芝 《广西医学》2002,24(2):153-155
目的:应用原位PCR技术检测B细胞系恶性淋巴瘤。方法:采用免疫球蛋白重链(IgH)基因第三互补决定区(CDR-Ⅲ)的引物,dig-11-dUTP标记物,应用直接原位PCR技术检测Ⅲ-Ⅳ级恶性淋巴瘤的间期淋巴细胞,结果:在初诊的15例恶性淋巴瘤患中,12例检测到IgH基因重排;4例临床表现呈现淋巴瘤性白血病患,治疗后骨髓完全缓解,2例间期细胞原位PCR仍显示有IgH基因重排,6个月复发,结论:间期细胞原位PCR技术能敏感、准确地检测Ⅲ级以上的恶性淋巴瘤,并帮助预测复发,为一有效的基因诊断方法。  相似文献   
102.
Although there are effective antibacterial agents against plague, newer antibacterial agents have been developed which show more potent activity against other bacterial organisms, but have not been tested againstYersinia pestis. A strain ofYersinia pestis was selected (no. 22; National Institute of Infectious Diseases, Tokyo, Japan) that caused a systemic infection in mice.Y. pestis no. 22 was intraperitoneally inoculated into DDY-strain mice, and 13 oral or 6 injectable antibacterial drugs given to the infected mice at varying doses 1 and 24 hours after infection. Levofloxacin, sparfloxacin and ofloxacin were the most effective oral agents against the infection, and prulifloxacin and pazufloxacin were also effective but to a lesser extent. Also, gentamicin and arbekacin were the most potent injectable antibacterial agents againstY. pestis. These results suggest that there are several new drugs, both oral and injectable, which exert excellent in vivo antibacterial activity against a mouse infection model and may be useful for the clinical treatment of plague.  相似文献   
103.
Basic fibroblast growth factor (bFGF) has been shown to be involved in epiretinal membrane formation in proliferative vitreoretinal disorders. However, up to now, little knowledge exists, as to the actual cellular source of this potent mitogen.We examined 20 epiretinal membranes from patients with proliferative diabetic retinopathy (PDR) (n = 12) and proliferative vitreoretinopathy (PVR) (n = 8) for the presence of bFGF peptide, fibroblast growth factor receptor-1 (FGFR-1) and bFGF messenger ribonucleic acid (mRNA).Using a specific antibody, we detected bFGF peptide in most (8/10) examined PDR membranes and in all (8/8) PVR membranes. Moreover, we found positive staining for the corresponding receptor.Local production of bFGF in epiretinal membranes was confirmed by nonisotopic in situ hybridisation for bFGF mRNA in some (4/7) examined PDR membranes and some (3/4) examined PVR membranes. All membranes which contained bFGF mRNA were also positive for bFGF peptide.In conclusion, bFGF is produced and stored in epiretinal membranes. Together with the corresponding receptor, bFGF may play a role in the auto- and paracrine control of the proliferative processes at the vitroretinal interface.Abbreviations aFGF acidic fibroblast growth factor - bFGF basic fibroblast growth factor - FGFR-1 fibroblast growth factor receptor-1 - mRNA messenger ribonucleic acid  相似文献   
104.
105.
While adult mice receiving picrotoxin (PTX) alone responded with clonic and tonic-clonic seizures, this response was greatly suppressed for mice simultaneously injected with 2,3-butanedione monoxime (BDM). For example, 60% and 10% of the mice convulsed when injected (i.p.) with 3.0 mg/kg PTX alone or PTX plus 205 mg/kg of BDM, respectively. In contrast, a non-oxime analogue of BDM, 2,3-butanedione (BTD), did not have this anticonvulsant effect. In order to explore the basis for the anticonvulsant effect of BDM, we recorded GABA-activated currents (IGABA) of frontal cortical as well as ventromedial hypothalamic neurons before, during and after exposure to this oxime. BDM had a biphasic effect on concentrations (100 μM-40 mM) decreased and lower concentrations (0.01 μM–0.001 μM) potentiatedIGABA; these effects of BDM reversed upon washout of the oxime. In contrast, BTD had no effect onIGABA. Finally, when 0.001 μM BDM, 10–30 μM PTX and GABA were co-applied the inhibitory effect of the toxin onIGABA was markedly suppressed. These data suggest that the anticonvulsant effect of oximes involves facilitation of the inhibitory action of GABA.  相似文献   
106.
豚鼠耳蜗微血管内皮细胞体外通透性的研究   总被引:1,自引:0,他引:1  
目的 研究豚鼠耳蜗微血管内皮细胞的体外通透性特征。方法 在成功建立豚鼠耳蜗微血管内皮细胞体外通透性模型的基础上 ,研究该体外模型跨细胞电阻及对12 5I 牛血清白蛋白的通透性。结果 ①耳蜗微血管内皮细胞在培养增殖过程中其跨细胞电阻呈动态变化过程 ,以 5× 10 4/cm2 的细胞密度接种时 ,7d左右电阻到达峰值 ,其跨细胞电阻峰值大小为 (118 9± 18 5 )Ω/cm2 ;②体外模型中加入12 5I 牛血清白蛋白后 ,其通透性呈上升期抛物线型曲线 ,90min内几乎呈直线。结论 跨细胞电阻及对12 5I 牛血清白蛋白变化曲线能反映体外耳蜗微血管内皮细胞的通透性特征  相似文献   
107.
With the advent of genomics, combinatorial paradigms and high-throughput screen (HTS)-based pharmacological testing, the number of compounds flowing through the discovery pipeline is likely to escalate. At the same time, with increased knowledge of the human drug-metabolizing enzymes and the availability of in vitro absorption-metabolism (AM) models, Preclinical Drug Metabolism is poised to meet the challenges of HTS. In order to be successful, however, a rational HTS strategy (vs. serendipitous HTS) has to be employed. Such a strategy is based on automation, validation and integration of in vitroAM models and database management (AVID). A generalized strategy for rational (AVID-based) HTS in Preclinical Drug Metabolism is described briefly.  相似文献   
108.
目的 研究透明质酸钠玻璃体腔内充填对严重开放性眼球损伤预后的影响。方法 在严重开放性眼球损伤一期手术缝合后玻璃体腔内充填透明质酸钠至眼压Tn。结果 用透明质酸钠在玻璃体腔内充填,眼球萎缩的发生率(6.67%)明显低于用BSS液充填的发生率(70.58%)。结论 透明质酸钠玻璃体腔内充填在严重开放性眼球损伤治疗中的应用对眼球外形维持和视功能恢复有重要作用。  相似文献   
109.
We examined changes in the expression of glial fibrillary acidic protein (GFAP) mRNA during Wallerian degeneration in the corticospinal system of the adult Golden hamster following axotomy. GFAP is the product of a type III intermediate filament (IF) gene that is expressed specifically in mature astrocytes. A well-studied component of a complex response termed reactive astrogliosis that occurs after various types of CNS injury is the increased production of astrocytic processes filled with GFAP-containing IFs. While increased expression of GFAP during reactive astrogliosis has been well established at the protein level, little is known about whether or not changes in GFAP mRNA levels occur after CNS injury. In the present study we used in situ hybridization methods to examine this issue. A 35S-labeled mouse GFAP cDNA probe was used for in situ hybridizations of sections of the brain stem obtained 2, 7, and 14 days after unilateral transections of the corticospinal tract in the caudal medulla. Film as well as emulsion autoradiography showed a dramatic increase in GFAP mRNA labeling associated with the degenerating corticospinal tract. GFAP mRNA levels were already dramatically increased in the injured corticospinal tract by 2 days post axotomy and remained elevated at 14 days. Interestingly, in addition to the robust increase in GFAP mRNA levels specifically associated with the degenerating tract, a diffuse increase in GFAP mRNA labeling was observed throughout the grey matter of the brain stem at 2 days post-axotomy, but not after this time. Immunoblotting and immunocytochemical experiments verified that the increased GFAP mRNA levels in the degenerating corticospinal system were accompanied by an increased expression of the protein. These results demonstrate that an increase in GFAP mRNA levels occurs during Wallerian degeneration in the CNS and suggest that increased expression of the GFAP gene is a major contributor to CNS scarring that results after direct traumatic injury.  相似文献   
110.
为比较正常人和尿石症患者尿液中凝血酶原片段1(UPTF1)在含量及其与草酸钙晶体的结合能力,以探讨UPTF1含量或功能异常与草酸结石形成的关系,用ELISA法检测正常人和尿石症患者24h尿液、用过饱和结晶法制备的晶体表面结合物质和结石基质中UPTF1的含量。结果发现尿石症患者尿液中能与草酸钙结合的UPTF1的浓度及其在24h尿中含量显著低于正常人组;UPTF1普遍存在于含钙结石中。结果表明:尿石症患者尿液中抑制结石形成的UPTF1明显减少可能是结石形成的重要原因。  相似文献   
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