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91.
经左颈静脉肝内门腔静脉支架分流术(附12例报告) 总被引:4,自引:0,他引:4
为解决肝硬变门脉高压患者在经颈静脉肝内门腔静脉支架分流术中右颈静脉窄或闭的难题,我们做了经左颈静脉途径完成肝内门腔分流术的尝试。自1993年7月至1995年8月,共178例TIPSS操作中发现12例右颈静脉狭窄或闭塞。其方法为经左颈内静脉穿刺、插管入路。 相似文献
92.
93.
Tissue distribution metabolism and excretion of 2,2′,4,4′, 5-pentachlorodiphenyl ether in the rat 总被引:1,自引:0,他引:1
E. Komsta I. Chu D. C. Villeneuve F. M. Benoit D. Murdoch 《Archives of toxicology》1988,62(4):258-262
The tissue distribution, metabolism and excretion of 14C-2,2,4,4,5-pentachlorodiphenyl ether (PCDE) were studied in the rat. Radioactivity was distributed in all tissues examined, with the highest concentrations being found in the fat followed by the skin, liver, kidney and muscle. Most of the radioactivity found in the tissues was due to unchanged PCDE. Decay of PCDE in the blood was fitted to a four-compartment pharmacokinetic model, and the last compartment had a half-life of 5.8 days. A total of 55% and 1.3% of an orally administered dose was excreted in feces and urine, respectively, in 7 days. More than 64% of the fecal radioactivity was due to unchanged PCDE, while hydroxylated PCDE accounted for 23%. 相似文献
94.
二氧化硅活化巨噬细胞中早期生长反应因子-1及其信号转导通路的研究 总被引:3,自引:0,他引:3
目的 探讨早期生长反应因子(Egr-1)及其信号转导在矽肺发生发展中的作用。方法用细胞免疫荧光、原位杂交方法检测二氧化硅(SiO2)刺激后Egr-1的表达定位,用报道质粒及EMSA检测其活性改变;用激酶活性分析法检测si0:刺激巨噬细胞后ERK1/2活性改变,进一步用激酶抑制剂初步探讨SiO2活化Egr-1的信号转导通路。结果SiO2刺激RAW264.7细胞短时间Egr-1核蛋白表达及转录因子明显增加;且在处理后30~60min,Egr-1核蛋白结合活性明显升高(为未处理组的20倍);在刺激后15min ERK1/2活性开始升高,30min达高峰(活性为对照组的29倍)而后渐降至基础水平;进一步用激酶阻断发现,Egr-1 mRNA及蛋白表达均减少。结论SiO2能激活巨噬细胞中Egr-1,且此过程可能由ERK1/2、p38介导,提示SiO2-ERK1/2、p38-Egr-1通路可能在矽肺发生发展过程中起重要作用。 相似文献
95.
A two decade survey of respiratory adenovirus in Taiwan: the reemergence of adenovirus types 7 and 4 总被引:3,自引:0,他引:3
Lin KH Lin YC Chen HL Ke GM Chiang CJ Hwang KP Chu PY Lin JH Liu DP Chen HY 《Journal of medical virology》2004,73(2):274-279
From November 1999 to December 2001, three outbreaks of adenovirus (Ad) respiratory infection occurred in southern Taiwan. To determine the circulating serotypes and molecular epidemiology, a total of 524 virus strains were randomly selected from 1,064 strains isolated from 1981 to 2001, and were studied using restriction fragment length polymorphism (RFLP) and polymerase chain reaction (PCR)-RFLP. The major subgenus found was subgenus B (45%), followed by subgenus E (29%) and subgenus C (25%). Ad3 and Ad7 were the major types found during the 1st outbreak, which occurred from November 1999 to March 2000, while Ad4 was found mainly during the 2nd and 3rd outbreaks in October 2000 and September 2001, respectively. Both Ad7 and Ad4 were reemerged serotypes, whereas Ad3 was consistently isolated during the survey, although it declined drastically from 36 to 2% in 2001. Genotype analysis in this study showed that the only strain of Ad7 found in 1983 was Ad7a, but all randomly selected strains of Ad7 isolated during 1999-2000 were Ad7b. The clinical features of 217 patients were analyzed during the 1999-2000 outbreaks. About 79% of the total cases were less than 7 years old. The ratio of male to female was 2:1. Severe infections, such as pneumonia and acute bronchitis, accounted for nearly half of the cases (43%). These results show the reemergence and changing of serotypes, the clinical association of respiratory adenovirus infections, and the molecular epidemiology of Ad7 genotypes in Taiwan during the past two decades. 相似文献
96.
97.
Chu PH Yeh HI Jung SM Chien LY Cheng NF Wu HH Chu JJ Hsueh C Lee YS 《Virchows Archiv : an international journal of pathology》2004,444(4):383-386
Cardiac hamartomas are very rare and are demarcated masses of enlarged, hypertrophied, mature myocytes and collagen tissue. Cardiac hamartomas are generally circumscribed in the right ventricle or atrium, but not reported in the crista terminalis (CRT). The CRT is crucial in electrophysiology, is related to arrhythmogenesis, and is targeted by radiofrequency catheter procedures. Previous works only described the benign natures of prominent CRT using non-invasive methods. This study describes an unusual cardiac hamartoma originating from the CRT and extending toward the tricuspid valve. Microscopically, this hamartoma comprised dense collagen and adipose tissue, mixed with hypertrophy, but with disarrayed cardiomyocytes. An irregular gap junction, connexin43, was demonstrated in this cardiac hamartoma. 相似文献
98.
Yu-Sheng Chang Pao-Hsien Chu Shih-Ming Jung Kun-Eng Lim Jaw-Ji Chu Chuen Hsueh Ying-Shiung Lee 《Cardiovascular pathology》2005,14(2):104-106
Cardiac papillary fibroelastoma (CPF) is the second most common benign neoplasm of the heart. This study describes the case of an 81-year-old man who was admitted to the hospital for severe vertigo and in whom a tumor at the right ventricular outflow tract (RVOT) was identified incidentally during echocardiography. The CPF was excised smoothly following the confirmation of its position by computed tomography. The comprehensive pathologic findings of CPF were reviewed. Detailed immunohistochemical analyses of CD34 and factor VIII-related antigen were performed on the covering endocardial cells. The unique chondroid metaplasia of fibrous tissue in this CPF has never been reported. This work is the first to present an unusual CPF at the RVOT with reactive process of fibrous connective tissue. 相似文献
99.
Determination of optimal cryoprotectants and procedures for their addition and removal from human spermatozoa 总被引:9,自引:7,他引:9
The objective was to test the hypothesis that the optimal cryoprotective
agent for cryopreservation of human spermatozoa would be a solute for which
cells have the highest plasma membrane permeability, resulting in the least
amount of volume excursion during its addition and removal. To test this
hypothesis, theoretical simulations were performed using membrane
permeability coefficients to predict optimal procedures for the addition
and removal of a cryoprotectant. Simulations were performed using data from
four different cryoprotectants: (i) glycerol, (ii) dimethyl sulphoxide,
(iii) propylene glycol and (iv) ethylene glycol. Thermodynamic formulations
were applied to determine approaches for the addition and removal of 1 M
and 2 M final concentrations of cryoprotectant, allowing the spermatozoa to
maintain a cell volume within their osmotic tolerance limits. Based on
these data, ethylene glycol was predicted to be optimal for minimizing
volume excursions among the solutes evaluated. These predictions were then
experimentally tested using glycerol as the control cryoprotectant and
ethylene glycol as the experimental cryoprotectant. The results indicate
that there was a higher (P < 0.05) recovery of motile spermatozoa after
cryopreservation when using 1 M ethylene glycol than with 1 M glycerol,
supporting the hypothesis that use of the cryoprotectant for which the cell
has the highest permeability will result in higher cell survival.
相似文献
100.
Yongchuan Chai Yu Wang Hua Qian Bo Yang Chao Wu Jiusheng Chu Tao Yang 《American journal of medical genetics. Part A》2019,179(2):243-248
Waardenburg syndrome (WS) is a genetic disorder characterized by hearing loss and pigmentary abnormalities with variable penetrance. Though heterozygous mutations in MITF are a major cause for Waardenburg syndrome type 2 (WS2), homozygous mutations in this gene and the associated phenotype have been rarely characterized. In this study, we identified a novel p.R223H mutation in MITF in a Chinese Han family with variable WS features. Both parents carried a heterozygous p.R223H mutation. They had normal hearing, and premature greying of the hair is their only pigmentary abnormality. In contrast, their two children both carried a homozygous p.R223H mutation and had classic WS features including profound hearing loss, heterochromia irides and marked pigmentary abnormalities in hair and skin. Interestingly, the two affected children also have persistent chronic constipation since the neonatal period, symptoms suggestive of Waardenburg syndrome type 4 (WS4). Our study revealed a likely association between homozygous mutations in MITF and WS4, which implies a dosage effect for the underlying pathogenesis mechanism. 相似文献