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排序方式: 共有538条查询结果,搜索用时 8 毫秒
531.
Congenital closed spinal anomalies are associated with distortion of the spinal cord, the spinal nerve roots or both, and can result in neurological abnormalities of the lower limbs and neuropathic bladder dysfunction. This study reports clinical and videourodynamic findings in a group of 51 patients with closed spina bifida. The mean age at presentation to a specialist neurological clinic was 3.3 years. Twenty five patients presented with urinary tract disturbance and 12 presented with neurological problems. Thirty three had normal neurological examination or only minor objective signs, 21 had normal renal tract ultrasonography but only two patients had normal videourodynamics, with 31 having two or more abnormalities during this assessment. Neither clinical neurological assessment nor the history of voiding behaviour are reliable indicators of bladder dysfunction and subsequent risk of renal damage. Therefore, all patients with a known or suspected diagnosis of closed spina bifida should have videourodynamic assessment. 相似文献
532.
目的:克隆人T-bet基因,构建其真核表达载体pEGFP-C1-T-bet。方法:实验于2005-07/2006-07在北京大学深圳医院中心实验室完成。①根据Genebank的人T-bet基因的全长cDNA序列,设计合成一对附加BglⅡ和SalⅠ两个限制性内切酶酶切位点的特异性引物。②分离人外周血单个核细胞,提取RNA,用反转录-聚合酶链反应方法将T-bet的编码序列cDNA扩增,装入pMD18-T载体并送去测序。③BglⅡ SalⅠ双酶切质粒pMD18-T-bet,经琼脂糖电泳切胶回收T-bet片段,将T-bet插入载体pEGFP-C1构建成重组真核表达载体pEGFP-C1-T-bet。④用双酶切和聚合酶链反应对插入片段进行分析和验证。结果:①反转录-聚合酶链反应产物经琼脂糖电泳结果显示在预期位置有相对分子质量为1608bp的特异性扩增带。②测序结果证实,T-bet的编码序列和Genbank中T-bet mRNA序列相同。③双酶切和聚合酶链反应结果证实插入片段序列正确。结论:实验成功扩增出人T-bet基因,构建了基因重组真核表达载体pEGFP-C1-T-bet,为探索T-bet基因对免疫细胞的调节作用和肿瘤基因治疗奠定了基础。 相似文献
533.
Purpose: To review issues related to the use of augmentative systems with young children and present a case study of one child and family's experience with the System for Augmenting Language (SAL). Method: The case involved a preschool child with severe developmental delays who had little functional speech. Acquisition and use of graphic symbols on a speech-output communication device was studied in home and clinical settings. Language and communication behaviours of the child and his communication partners were observed and language assessment measures were collected. Results: Child engagement state varied across the two settings with a stable profile seen in the therapy setting and a clear increase at home. Child communicative attempts increased following the introduction of the augmented system. Parents reported successful use of the SAL. Conclusion: SAL is a viable communication intervention approach for young children. 相似文献
534.
AIM: To study endothelial function in different variants of acute renal failure (ARF) at various stages of the disease. MATERIAL AND METHODS: The study of 36 patients with severe ARF at the stages of oliguria and recovery of diuresis included a clinico-laboratory analysis of characteristics of ARF of various etiology and follow-up of plasmic concentrations of endothelin-1, thromboxan A2 and prostacyclin in different ARF variants at different ARF stages. RESULTS: The oliguric phase of severe ARF ran with significant elevation of the level of vasoconstrictive endothelial hormones (endothelin-1 and thromboxan A2 and a fall of a vasodilator prostacyclin. Recovery of diuresis normalized the above parameters. CONCLUSION: Mechanisms of ARF development involve endothelial dysfunction manifesting with alteration of vasoactive hormones synthesis with a dominant rise of a vasoconstrictive hormones concentration. 相似文献
535.
Complement-mediated lysis by anti-CD20 mAb correlates with segregation into lipid rafts 总被引:8,自引:5,他引:8
Cragg MS Morgan SM Chan HT Morgan BP Filatov AV Johnson PW French RR Glennie MJ 《Blood》2003,101(3):1045-1052
Despite the clinical success of anti-CD20 monoclonal antibody (mAb) in the treatment of lymphoma, there remains considerable uncertainty about its mechanism of action. Here we show that the ability of mAbs to translocate CD20 into low-density, detergent-insoluble membrane rafts appears to control how effectively they mediate complement lysis of lymphoma cells. In vitro studies using a panel of anti-B-cell mAbs revealed that the anti-CD20 mAbs, with one exception (B1), are unusually effective at recruiting human complement. Differences in complement recruitment could not be explained by the level of mAb binding or isotype but did correlate with the redistribution of CD20 in the cell membrane following mAb ligation. Membrane fractionation confirmed that B1, unlike 1F5 and rituximab, was unable to translocate CD20 into lipid rafts. In addition, we were able to drive B1 and a range of other anti-B-cell mAbs into a detergent-insoluble fraction of the cell by hyper-cross-linking with an F(ab')(2) anti-Ig Ab, a treatment that also conferred the ability to activate lytic complement. Thus, we have shown that an important mAb effector function appears to be controlled by movement of the target molecule into membrane rafts, either because a raft location favors complement activation by mAbs or because rafts are more sensitive to complement penetration. 相似文献
536.
目的:介绍脐血干细胞和胎盘间充质干细胞的研究进展,以及干细胞在妇产科中的应用前景。资料来源:应用计算机检索Medline1996-01/2006-12与脐血干细胞和胎盘间充质干细胞、以及干细胞在妇产科中的应用相关的文章,检索词为“human cord blood,mesenchy malstem cell,placenta,gene therapy in the uterus”,限定文献语种为“English”;同时检索万方数据库2000-01/2006-12相关文章,检索词为“脐血,间充质干细胞,胎盘,宫内治疗,卵巢癌,子宫癌”,限定文献语种为中文。资料选择:共检索到相关文献500余条,进一步查找全文,优先选择与临床应用靠近的文章,无论观察对象是人还是动物均纳入,筛除干细胞的提取、分化或培养等基础类研究,明显重复和综述文献也排除,最后纳入31条文献进行综述。资料提炼:31条文献中论述脐血干细胞和胎盘间充质干细胞的特点及应用文章有26篇,关于宫内移植干细胞治疗的文章有2篇,其他为研究干细胞在妇产科中应用的文章。资料综合:①大量实验证明脐血是骨髓、外周血后的第3种非常有潜力的造血干细胞资源。目前应用脐血移植治疗的疾病有急(慢)性白血病、恶性淋巴瘤、多发性骨髓瘤、再生障碍性贫血、严重免疫缺陷症等,而且已经有一定疗效。②胎盘作为胚胎发育中维系母体和胎儿氧气及营养物质交换的重要暂时性器官,无论从解剖结构还是在发育行为上,都包含了较为幼稚的胚胎及趋于成熟的成体干细胞成分,而且胎盘不会涉及伦理道德问题,目前已成为寻找人类间充质干细胞新来源及提高临床应用效果的研究热点。③干细胞宫内移植为先天性疾病治疗开辟了一条新途径。另外干细胞在器官再造、男性不育治疗和保存生育能力等生殖医学领域的研究也取得了重大进展,在妇科肿瘤方面,如以化疗保护为目标的基因治疗已逐步应用于临床。结论:脐血和胎盘取材方便、安全,还能避免免疫排斥和伦理问题,已成为人类间充质干细胞新来源。干细胞在宫内治疗、生殖疾病和妇科肿瘤方面也有广泛的临床应用前景。 相似文献
537.
Seferian KR Tamm NN Semenov AG Mukharyamova KS Tolstaya AA Koshkina EV Kara AN Krasnoselsky MI Apple FS Esakova TV Filatov VL Katrukha AG 《Clinical chemistry》2007,53(5):866-873
BACKGROUND: Peptides derived from brain natriuretic peptide (BNP) precursor (proBNP), BNP, and the N-terminal fragment of proBNP (NT-proBNP) are used as biomarkers of heart failure. It remains unclear which forms of these peptides circulate in blood and which forms are measured by assays for these natriuretic peptides. METHODS: To design assays for immunodetection of proBNP, NT-proBNP, and BNP, we used a panel of BNP- and NT-proBNP-specific monoclonal antibodies (MAbs). All MAbs were tested in 2-site combinations in time-resolved fluoroimmunoassays with recombinant or synthetic antigens and plasma from heart failure (HF) patients. ProBNP and related molecules were assayed in HF plasma samples and plasma extracts by means of gel filtration fast protein liquid chromatography (FPLC) before and after protein fractionation on Sep-Pak C18 cartridges. RESULTS: The limits of detection for BNP, proBNP, and NT-proBNP assays were 0.4, 3, and 10 ng/L, respectively. Gel filtration-FPLC studies revealed 1 peak of NT-proBNP (approximately 25 kDa), 1 peak of proBNP (approximately 37 kDa), and 2 peaks of BNP immunoreactivity, a major peak (approximately 37 kDa) for proBNP, and a minor peak (approximately 4 kDa) for BNP. In patient plasma, the molar concentration of NT-proBNP was almost 10 times that of proBNP. The mean proBNP:BNP ratio in patient plasma was 6.3, ranging from 1.8 to 10.8. CONCLUSIONS: ProBNP is the major BNP-immunoreactive form in human blood. The proBNP:BNP ratio in plasma samples is dependent on the methods used for sample handling and for the measurement of the peptides. 相似文献
538.