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991.
Deficient expression of enhanced reactivation of parvovirus H-1 in ataxia telangiectasia cells irradiated with X-rays or u.v. light 总被引:1,自引:0,他引:1
Cells of patients with ataxia telangiectasia (AT), an inheriteddisease characterized by a high propensity to cancer, are hypersensitiveto ionizing radiation. We investigated whether the hyper-radiosensitivityof AT cells correlated with a defect in their constitutive and/orconditional ability to rescue a damaged exogenous virus. Forthat purpose, parvovirus H-1, a single-stranded DNA virus whoseintranuclear replication mostly relies on host cell functions,was used as a probe. The survival of u.v.-or -irradiated H-1was measured in X-, u.v.- or mock-irradiated human cells ofnormal (NB-E) or AT (AT5BIVA) origin. -irradiated H-1 survivedto similar extents in untreated normal and AT cell lines. BothX- and u.v.-irradiatlon induced normal cells to achieve an enhancedreactivation (ER) of -- or u.v.-damaged H-1. In contrast, neitherdose-effect curves nor time course revealed significant levelsof ER expression after X- or u.v.-irradiation in AT5BIVA cells.Our results suggest that the impairment of ER of damaged parvovirusesmay constitute a marker of the AT cell phenotype and be relatedto the radiosensitivity of AT cells. 相似文献
992.
Radiologic and manometric correlation in "nutcracker esophagus" 总被引:1,自引:0,他引:1
D J Ott J E Richter W C Wu Y M Chen D W Gelfand D O Castell 《AJR. American journal of roentgenology》1986,147(4):692-695
"Nutcracker esophagus" is a newly described esophageal motor disorder seen in some patients with chest pain and/or dysphagia and characterized manometrically by normal primary peristalsis with distal contractions of high amplitude. The radiographic and manometric examinations in 20 patients with nutcracker esophagus were correlated. Normal primary peristalsis was observed radiographically in 16 patients, and a nonspecific motor disorder was diagnosed in the remaining four patients. Mild-to-severe nonspecific tertiary activity was seen in about half of the patients, esophageal wall thickness was normal. It is concluded that nutcracker esophagus is primarily a manometric diagnosis made in the appropriate clinical setting, and that the radiographic findings are normal or nonspecific. 相似文献
993.
本文报道一例用病理组织学、免疫组织化学和免疫电镜综合确诊的多克隆性IBL样T细胞性淋巴瘤。讨论了这三种病理研究手段综合应用在本例诊断中的意义。指出免疫电镜在确定阳性反应细胞的细微形态上较光镜有明显优越性。 相似文献
994.
癌光啉对动物移植瘤的光化学诊治作用 总被引:11,自引:0,他引:11
本文报道了肿瘤光化学诊治新药癌光啉(PsD-007)对三种动物移植瘤(S_(180)肉瘤、Lewis肺癌、U_(14)宫颈癌)的实验性光化学诊治效果,初步探讨了辐照光能量和药物剂量与肿瘤实验性诊治效果的关系。作者采用“透镜光阑”法改善辐射光斑内功率密度分布的不均匀性。提供了一种能比较客观地评价药物对动物移植瘤的光动力学治疗效价的模型体系。 相似文献
995.
A history of the discovery of cholera pathogen] (Chi) 总被引:1,自引:0,他引:1
Chen W 《Zhonghua yi shi za zhi (Beijing, China : 1980)》1984,14(2):104-106
996.
VALUE AND LIMITATIONS OF SINUS NODE FUNCTION TE.ST
BY ATRIAL PACING IN SICK SINUS SYNDROME DIAGNOSIS
Sun Rui-long孙瑞龙 Chen Xin陈新 Wang Fang-zhengHu Sheng-jun胡绳俊 Tian Rui-guo田瑞国and Qi Lian-xiaClinical Electrophysiology Laborato''ry Institute of Cardiovascular Diseases Chinese Academy of Medical Sciences Beijing 《中华医学杂志(英文版)》1984,97(2):142-146
In order to evaluate the significance of the
sinus node function test by transvenous atrial
pacing in the diagno,sis of sick sinus syndrome
(SSS), sinus node recovery time (SRT), co]rrected
sinus node recovery time (CSRT) and total atrio-
sinus and sino-atrial conduction time (SACT)
are observed in 69 patients including non-SSS
group 39 cases and SSS group 30 cases.
According to our data, we suggest criteria
for sinus node dysfunction as follows. SRT>1,400
ms and/or A-V junctional esca.pe before sinus
recovery and;or secondary pause, CSRT>560 ms.
total SACT>300 ms. With l item abnormal, the
false positive rat.e in the non-SSS group is 7.7c7。
and the false negative rate in the S.SS group 3.30i"
with 2 items abnormal, the false positive rate in
the non-SSS group Oi and the false negative
rate in the SSS grOiup 6.7'70.
Atropine test results are compared with that
of atrial pacing, 95.8To and 84.2% are compatible
with each other in these 2 groups. In order to
cut the use of invasive technic to the minimum,
we propose performing the atropine test first.
Only in those with unexplainable test results
should the trial pacing test. be resorted to.. 相似文献
997.
Quality of Life Research - This study aims to provide new knowledge on the relative importance of key life domains amongst older adults, and how the Coronavirus pandemic has influenced their life... 相似文献
998.
Quality of Life Research - To evaluate and compare the test–retest reliability of discrete choice experiments with duration (DCETTO) and time trade-off (TTO) in the Chinese SF-6Dv2 valuation... 相似文献
999.
Health Care Analysis - Pharmaceutical sales representatives (PSRs) are one of the most frequently used drug information sources for physicians in both the United States and China. During... 相似文献
1000.
目的:采用超高效液相色谱-线性离子阱-静电场轨道阱高分辨质谱法(UPLC-LTQ-Orbitrap-MS)快速鉴定痛泻要方水煎液中的化学成分。方法:色谱条件为ACQUITY UPLC BEH C18色谱柱(2.1 mm×100 mm,1.7μm),流动相0.1%甲酸水溶液(A)-乙腈(B)梯度洗脱(0~4 min,5%~15%B;4~10 min,15%~25%B;10~15 min,25%~60%B;15~20 min,60%~90%B;20~25 min,90%~100%B;25~27 min,100%B;27~30 min,100%~5%B;30~32 min,5%B),流速0.3 m L·min-1,进样量3μL,柱温35℃。质谱条件为电喷雾离子源(ESI),扫描范围m/z 100~1 250,正、负离子模式下分别采集MS、MS/MS数据。结合对照品、数据库和文献信息,运用Trace Finder 4.1和Xcalibur 2.1软件对痛泻要方水煎液进行化学成分鉴定。结果:在正、负离子模式下,从痛泻要方水煎液中共鉴定出90个化合物,主... 相似文献