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排序方式: 共有682条查询结果,搜索用时 31 毫秒
1.
不同时期的典型何杰金氏病18例,用抗PC_(10)、L_(26)、UCHL-1抗体作SP免疫组化染色。结果显示:无一例阴性病例。PC_(10)阳性的HRS细胞百分率与传统分类比较有相关性。L_(26)和UCHL_1阳性细胞的百分率分别为11.3%~21.5%和38.2%~49.5%。表明不存在单一的B或T细胞免疫表达。提示HRS细胞与背景中淋巴细胞之间其细胞来源有内在联系。 相似文献
2.
ThedynamicdistributionofnitricoxidesynthaseinthesmallintestineofmicewithintestinalradiationsicknessWeiLichun(魏丽春);GuoYao(郭鹞)(... 相似文献
3.
作者曾经体外实验证明,均聚寡脱氧胞嘧啶核苷酸片段(dC14)有抗病毒活性,现继续研究其在体内的作用。不给dC14的对照组小鼠,接种腹水瘤细胞后:100%发病和死亡,潜伏期为6d,存活期11d;给每只小鼠dC14 1.3~3.2 mg,发病率和死亡率降低至20%,疾病潜伏期和存活期推迟。在未经dC14处理的种瘤细胞和淋巴组织与经处理的淋巴组织中,多聚酶链反应(PCR)法都检测到病毒核酸,而正常小鼠中则无此种病毒核酸顺序。研究结果提示,dC14对小鼠SRS腹水瘤的发病和生长有抑制作用。此种抑制作用可能是通过抑制病毒基因的表达来实现的。 相似文献
4.
Lichun Zhong Eugenia Chu Jane Chu Teh-Ching Chu 《Journal of ocular pharmacology and therapeutics》2003,19(5):425-436
It has been demonstrated that natriuretic peptides lower intraocular pressure, however, the underlying cellular mechanism(s) mediating this response remain(s) to be determined. The purpose of this study was to investigate the effects of C-type natriuretic peptide (CNP) on pH(i), cGMP/cAMP and expression of atrial natriuretic peptide receptor (NPR-A), brain natriuretic peptide receptor (NPR-B) and C-type natriuretic peptide receptor (NPR-C), in HTM cells. At concentrations of 10(-7) M, CNP caused an acidification of pH(i). In addition, CNP caused a dose-dependent increase in cGMP formation and inhibition of forskolin-stimulated cAMP accumulation. These changes were not significantly altered in the absence of 10(-3) M isobutylmethylxanthine (IBMX). Treatment with the NPR-A antagonist, anantin, produced no influence on basal cGMP/cAMP levels, the CNP-stimulated cGMP accumulation and CNP-induced inhibition of forskolin-stimulated cAMP accumulation. However, CNP-induced reduction of forskolin-stimulated cAMP accumulation was inhibited by pretreatment with pertussis toxin (PTX). Furthermore, NPRB receptors were predominantly expressed and pretreatment with CNP (10(-7) M, 24hr) enhanced all NPR mRNAs expression which was not altered by higher concentrations or longer incubation. Results demonstrate that NPR-A, NPR-B and NPR-C receptors' expression can be up-regulated by CNP treatment. CNP activates NPR-B receptors preferentially to increase cGMP accumulation and acts through the PTX-sensitive cAMP-signaling pathway leading to a decrease in pH(i). 相似文献
5.
介绍了“四川联大Ⅰ型”(以下简称:SUUⅠ)管外流式(ELF)中空纤维膜式氧合器的研制、设计、外形制做及离心封端等过程,重点介绍了中空纤维膜材料选择,膜肺离心封端的原理、材料、设备及方法,并对聚氨酯胶进行离心封端的具体步聚作了较详细的叙述。作者根据自身在国外与国内的研制经验,认为离心封端的关键在于:(1)中空纤维膜材料的质量及成束质量;(2)聚氨酯封端胶材料固化特性的掌握及料量计算;(3)反应温度控制;(4)气体排除;(5)转速的控制;(6)纤维束的安装;(7)脱模和切头的时间掌握等方面。作者用外购的材料和自己设计制造的离心封端机成功地制造了我国第一个管外流式(ELF)中空纤维成人氧合器。SUUⅠ膜式氧合器的设计是作者在国外建立的交叉流式膜肺O2、CO2传递模型的具体应用。 相似文献
6.
7.
Qihan Li Lichun Wang Chenghong Dong Yanchun Che Li Jiang Longding Liu Hongling Zhao Yun Liao Yi Sheng Shaozhong Dong Shaohui Ma 《Journal of clinical virology》2005,34(2):133-139
The pathological mechanism of SARS-CoV infection was investigated. The gene for the SARS-CoV non-structural protein 10, which is located in the open reading frame of pp1a/pp1ab gene, was synthesized and used to screen for the specific cellular gene coding for the protein interacting with this nsp10 protein in a human embryo lung cDNA library using a yeast trap method. The results indicated that apart from the two subunits of cellular RNA polymerase complex, BTF3 and ATF5, this nsp10 protein was also able to interact specifically with the NADH 4L subunit and cytochrome oxidase II. Further study revealed that the activity of the NADH-cytochrome was altered and the inner mitochondrial membrane was depolarized in the transfected human embryo lung fibroblast by the nsp10 protein gene. The cytopathic effect of the Coronavirus 229E strain appeared more extensive in these cells than in the control cells. 相似文献
8.
Ko JM Yau WL Chan PL Lung HL Yang L Lo PH Tang JC Srivastava G Stanbridge EJ Lung ML 《Genes, chromosomes & cancer》2005,43(3):284-293
Despite the abundant evidence of high allelic loss of chromosome arm 14q in human cancers, tumor-suppressor genes mapped to this chromosome have yet to be identified. To narrow the search for candidate genes, we performed monochromosome transfer of chromosome 14 into an esophageal carcinoma cell line, SLMT-1 S1. Statistically significant suppression of the tumorigenic potential of microcell hybrids containing the transferred chromosome 14 provided functional evidence that tumor-suppressive regions of chromosome 14 are essential for esophageal cancer. Tumor segregants emerging in nude mice during the tumorigenicity assay were analyzed by detailed PCR-microsatellite typing to identify critical nonrandomly eliminated regions (CRs). A 680-kb CR mapped to 14q32.13 and an approximately 2.2-Mb CR mapped to 14q32.33 were delineated. Dual-color BAC FISH analysis of microcell hybrids and tumor segregants verified the selective loss of the 14q32.13 region. In contrast, similar transfers of an intact chromosome 11 into SLMT-1 S1 did not significantly suppress tumor formation. These functional complementation studies showing the correlation of tumorigenic potential with critical regions of chromosome 14 validated the importance of the 14q32 region in tumor suppression in esophageal cancer. The present study also paved the path for further identification of novel tumor-suppressor genes that are relevant to the molecular pathogenesis of esophageal cancer. 相似文献
9.
目的 :研究人体在高空吸纯氧及缺氧状态下对血清心肌酶及心率的影响。方法 :将实验者分为吸纯氧组和缺氧组及对照组 ,前两组在 5km高空吸纯氧或不吸氧 ,对照组不升空 ,分别测定血清天冬氨酸氨基转移酶 (AST)、乳酸脱氢酶(LDH)、肌酸激酶 (CK)、α 羟丁酸脱氢酶 (α HBCH)和心率变化。结果 :在 5km高空 ,缺氧时CK增高明显 (P <0 .0 5) ,血清心肌酶活性随吸纯氧时间延长有逐渐增高的趋势 ;吸纯氧时血清心肌酶活性随时间延长有逐渐增高的趋势 ,缺氧时心率随缺氧时间延长而逐渐加快。结论 :长时间吸纯氧或缺氧都将对机体产生损害 相似文献
10.
深圳市一孩先天性残疾家庭的二孩同类病研究 总被引:1,自引:0,他引:1
本文对深圳市1990~1997年因独生子女先天残疾通过病残儿鉴定再生育二孩的家庭进行调查,并以同期通过鉴定的后天性残疾家庭为内对照,以农村地区一孩先天残疾未经病残儿鉴定生育二孩的家庭为外对照,了解其二孩先天残疾再发情况,尤其是同类病的再发情况,拟对独生子女病残儿医学鉴定和二胎生育指标的审批工作效果进行评价,为优生工作提供依据。研究结果表明,鉴定组一孩先天残疾家庭二孩先天残疾的患病率为5.81%,与广州市1986~1991年情况类似(5.9%),高于外省(辽宁1990~1992年为1.35%)。鉴定组二胎同类病发生率为2.8%,非鉴定组为4.55%,两组比较虽无统计学差异,但病种上却有不同,鉴定组为再发风险低的血友病、先天性共转性内斜视、脑萎缩,而非鉴定组为再发风险高的先天聋哑、进行性肌萎缩。提示病残儿鉴定工作颇有成效,避免了相当一部分遗传病家庭再次生育残疾儿,但某些环节有待进一步完善;对农村一胎先天残疾家庭生育二胎也必须纳入管理范围。 相似文献