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991.
背景与目的:感染丙型肝炎病毒(HCV)的肝移植受体在肝移植术后很快进展为复发性肝炎,其中一些患在术后2年内即进展为肝纤维化。该项研究目的是识别影响肝脏疾病进展的分子机制,并寻求早期肝纤维化可能的基因标志物。方法:作对13例(11例感染和2例非感染)肝移植受体,分别在其移植术后1年之内的0、3个月、6个月和12个月对其肝活检标本进行连续性基因表达分析。将所得数据与临床观察结果进行比较,并与从55例非移植的丙型肝炎感染和非感染的肝脏活检标本获得的基因表达数据库进行比较。结果:识别出一些特殊的基因表达模式。第1种模式是移植受体所特有的,而与其是否存在感染无关,其相应的基因编码应激反应蛋白和涉及凝血的血蛋白,在移植术后移植物的恢复中有差异性表达;第2种模式为HCV感染所特有的,包括编码干扰素介导的抗病毒反应和免疫系统(抗原递呈,细胞毒反应)基因编码元件上调,而这些上调表达在进展为早期纤维化的患体内缺失或被抑制,从而提示患疾病的进展可能是由于肝脏对感染的反应受损所致;最后一种基因表达模式,是4例感染了HCV并进展为早期肝纤维化的患第12个月的肝活检标本所特有的。 相似文献
992.
993.
重庆市区主要交通干道苯并(a)芘污染状况及其危害分析 总被引:1,自引:0,他引:1
目的 了解重庆市区交通干道苯并(a)芘质量污染状况,分析其对人群健康的危害.方法 测定重庆市区主要交通干道空气中苯并(a)芘质量浓度、总悬浮颗粒、PM10、PM2.5和PM1浓度,分析各污染物之间的关系.结果 除隧道外,重庆市主要交通干道苯并(a)芘浓度最高为0.570 7μg/m3,TSP为1.516 7mg/m3,PM10为0.857 5 mg/m3,均超过国家环境卫生标准.结论 表明重庆市区大气中苯并芘[B(a)P]污染已极为严重,有必要对其引起的人群健康效应进行深入研究. 相似文献
994.
超声引导经皮微波消融治疗早期原发性肝癌的远期疗效 总被引:41,自引:1,他引:41
目的评价经皮微波消融治疗早期肝细胞肝癌患者的远期疗效。方法自1994年5月至2004年6月,216例直径≤5.0 cm的原发肝细胞肝癌患者共275个结节进行了经皮微波消融治疗(男性193例,女性23例;平均年龄54.68岁),所有病例均在我院诊治并签署知情同意书同意接受微波治疗。分析了肿瘤完全坏死率、远期生存率、复发率及并发症。结果本组平均随访期为40个月±24个月(6~127个月)。随访中159例(73.61%)存活,57例(26.39%)死亡。微波消融后95.64%(263/275)的肿瘤呈完全灭活,患者1、2、3、4和5年的累计生存率分别为94.87%、88.81%、80.44%、74.97%和68.63%。微波消融后1、2、3、4和5年的累计复发率分别为20.01%、32.04%、39.57%、44.97%和52.90%,3例发生较严重的并发症,包括针道种植1例,胆瘘2例,1例于治疗后一周死于肺部感染。结论超声引导经皮微波消融早期肝细胞肝癌在大部分病例可达到肿瘤完全坏死且并发症发生率较低,具有满意的远期临床疗效。 相似文献
995.
Perceived parental behaviour, self-esteem and happiness 总被引:4,自引:0,他引:4
Background: This study set out to determine to what extent recalled parental rearing styles (authoritarian, authoritativeness, permissiveness),
personality (extraversion, neuroticism, psychoticism, lie), and self-esteem predicted self-rated happiness in a normal, non-clinical,
population of young people in their late teens and early 20s. Methods: Each participant completed a few questionnaires: the Eysenck Personality Questionnaire (revised), the Rosenberg Self-Esteem
Scale, the Parental Authority Questionnaire and the Oxford Happiness Inventory. It was predicted that sex, extraversion, neuroticism,
self-esteem and both maternal and paternal authoritativeness would be significant predictors of happiness. Results: Regressional and path analysis showed self-esteem to be the most dominant and powerful predictor of happiness. The effect
of sex on happiness was moderated by neuroticism, which related to self-esteem, which directly influenced happiness. Stability,
extraversion and maternal authoritativeness were significant predictors of self-esteem accounting for one-third of the variance.
Conclusion: The results are considered in terms of the distinct literature on the relation between personality and happiness and on
the relation between parental styles and self-esteem. Self-esteem was both a direct and a moderator variable for young people's
self-reported happiness. Extraversion had both direct and indirect predictive power of happiness, whereas neuroticism predicted
happiness mediating through self-esteem. Maternal authoritativeness was the only direct predictor of happiness when paternal
and maternal rearing styles were examined together, suggesting that a reasonable discipline exercised by mothers towards their
children was particularly beneficial in enhancing the off-springs' self-esteem.
Accepted: 22 June 2000 相似文献
996.
Purpose: To investigate the relationships between the axonal sprouting and target neurotization by central neurons after nerve heterocon-nection. Methods: Unilateral (right) vagal-hypoglossal nerve anastomosis (VHA) was performed in adult cats. Following 3-315 days postoperation (dpo), quantitative analyses and ultrastructural changes in the proximal portion of the vagal-hypoglossal heteroconnected nerve as well as the time course of neuronal regeneration were studied. Along with this, horseradish peroxidase (HRP) retrograde tracing technique was used to label the neurons of dorsal motor vagal nucleus (DMV) and nucleus ambiguus (NA) to ascertain if target neurotization was established. Results: The contralateral (left) intact vagus nerve proximal to the level of ansa cervicalis showed an average of 33 +/- 1 myelinated and 74 +/- 4 unmyelinated axons in 727 &mgr;m(2) sectional area of the nerve. In the heteroconnected nerve at the corresponding level just proximal to the anastomosis site, there was a marked increase in the number of small axons sprouting from the unmyelinated nerve fibers between 18 and 25 dpo. The number of these axonal sprouts appeared to decline at 32 dpo but its increase of 131 % was sustained until the late regeneration stage at 315 dpo when compared with the contralateral nerve serving as a control. The mean number of myelinated axons per area unit (727 &mgr;m(2)) was reduced to 18 at 3 dpo but was immediately restored to the normal range at 7 dpo. The retrograde labelling of neurons in both the DMV and NA was first detected at 22 dpo and was progressively increased peaking by about 67 dpo. Conclusions: We conclude that compared with the unmyelinated axons, the myelinated axons may acquire a superior interaction with the new target. Furthermore, the postoperative neurotization of tongue muscles may initiate and facilitate the retraction of the redundant axonal sprouts. 相似文献
997.
998.
Intravenous amiodarone for prevention of atrial fibrillation after coronary artery bypass grafting 总被引:6,自引:0,他引:6
Lee SH Chang CM Lu MJ Lee RJ Cheng JJ Hung CR Chen SA 《The Annals of thoracic surgery》2000,70(1):157-161
BACKGROUND: Atrial fibrillation occurs in 10% to 40% of patients who undergo coronary artery bypass grafting. This prospective study assesses the safety and efficacy of low-dose intravenous amiodarone in the prevention of atrial fibrillation after coronary artery bypass grafting. METHODS: One hundred forty patients were randomly divided into two groups: an amiodarone group (n = 74) receiving intravenous amiadarone in a loading dose of 150 mg and maintenance dose of 0.4 mg x kg(-1) x h(-1) for 3 days before and 5 days after operation and a control group (n = 76) receiving matching infusions of 5% glucose solution. RESULTS: Atrial fibrillation occurred in 9 (12%) of the amiodarone group patients and in 26 (34%) of the control group patients during hospitalization (p < 0.01). The maximum ventricular rate during atrial fibrillation was significantly slower in the amiodarone group (107 +/- 21) than in the control group (138 +/- 24 beats per minute, p < 0.01). The duration of atrial fibrillation in the amiodarone group (1.1 +/- 1.2 hours) was significantly shorter than that in the control group (3.2 +/- 1.3 hours, p = 0.01). The two groups had no significant differences in incidence of major morbidity (8 of 74 versus 8 of 76 in amiodarone and control groups, respectively) or mortality (4 of 74 versus 5 of 76). However, the control group had significantly longer intensive care unit stays (132 +/- 24 versus 111 +/- 19 hours, p < 0.01). CONCLUSIONS: Perioperative low-dose intravenous amiodarone significantly reduces the incidence, ventricular rate, and duration of atrial fibrillation after coronary artery bypass grafting. Furthermore, low-dose intravenous amiodarone is well tolerated and does not increase the risk of intraoperative or postoperative complications. 相似文献
999.
1000.
Khan SS Siegel RJ DeRobertis MA Blanche CE Kass RM Cheng W Fontana GP Trento A 《The Annals of thoracic surgery》2000,69(2):531-535
BACKGROUND: The purpose of this study was to determine whether significant regression of left ventricular hypertrophy is seen after implantation of small sizes (19 to 23 mm) of the Carpentier-Edwards (CE) pericardial valve, a stented pericardial valve. METHODS: Echocardiograms and electrocardiograms (ECGs) were performed at least 1 year after surgery (mean 18 months) in patients with 19-, 21-, and 23-mm CE pericardial aortic valves and compared with preoperative echocardiograms and ECGs. RESULTS: A total of 41 patients, mean age 79 +/- 9 years (range 46 to 93 years), were studied, including 7 19-mm, 22 21-mm, and 12 23-mm patients. The mean postoperative gradient was 22 +/- 7 mm Hg for 19-mm valves, 18 +/- 5 mm Hg for 21-mm valves, and 16 +/- 4 mm Hg for 23-mm valves. The postoperative valve areas were 1.1 +/- 0.3 cm2 for the 19-mm, 1.3 +/- 0.3 cm2 for the 21-mm, and 1.5 +/- 0.4 cm2 for the 23-mm valves. Left ventricular end diastolic diameter, end systolic diameter, septal thickness, and posterior wall thickness all decreased significantly (p <0.05) postoperatively. The proportion of patients with significant left ventricular hypertrophy on ECG decreased from 63% to 47% (p = 0.001). Left ventricular mass decreased significantly by echocardiography from 265 g preoperatively to 208 g postoperatively (p = 0.004). Left ventricular mass decreased for each valve size, and the greatest absolute reduction in mass occurred in the 19-mm valve recipients. CONCLUSIONS: Implantation of the 19-, 21-, and 23-mm CE pericardial valves results in significant reductions in left ventricular mass. These findings suggest that stented pericardial valves can be used in the small aortic root without the need for aortic root enlargement procedures. 相似文献