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991.
Nosocomial postoperative endophthalmitis: a 14-year review   总被引:1,自引:0,他引:1  
Background The objective of this study was to evaluate the incidence, predisposing surgery, management and final visual outcome of postoperative endophthalmitis over a 14-year period at one institute.Methods This retrospective study reviewed all intraocular operations performed between 1 January 1991 and 31 August 2004 at Chang Gung Memorial Hospital, Kaohsiung Medical Center, to determine the incidence of nosocomial postoperative endophthalmitis and the characteristics of patients who developed this condition.Results The overall incidence of postoperative endophthalmitis after intraocular surgery was 0.19% (56 out of 30,219). Postoperative endophthalmitis developed in 56 eyes in 56 patients during the study period. The condition developed after cataract surgery in 46 eyes, after penetrating keratoplasty in 6 eyes, after filtering surgery in 2 eyes, after secondary intraocular lens implant in 1 eye, and after vitrectomy in 1 eye. Postoperative endophthalmitis was culture-positive in 31 cases (55%). The most frequent organism isolated was coagulase-negative Staphylococcus. Factors associated with better visual acuity outcomes included low virulence of isolated pathogen, initial visual acuity of counting fingers or better, and history of cataract surgery compared with other intraocular surgery.Conclusion The overall incidence of endophthalmitis after intraocular surgery was 0.19%. The results of this 14-year review from a local medical center may serve as a source of comparison for other centers and future studies.No proprietary interests  相似文献   
992.
二至丸由女贞子、墨旱莲两味药材组成,具有补益肝肾、滋阴止血的功效,在妇科疾病、肾病、肝病等领域均有广泛的临床应用基础。现代药理研究发现二至丸在保肝补肾、改善骨质疏松、围绝经期综合征、免疫调节、抗衰老、改善神经系统疾病等方面具有广泛的药理活性,并对二至丸保护肝脏、抗骨质疏松、抗衰老的作用机制与潜在通路开展了研究。对二至丸的药理作用研究进展进行综述,为进一步利用现代药理学手段阐明二至丸治疗肝肾阴虚证的机制、挖掘中药经典方“多成分、多靶点、多通路”的作用特点以及指导二至丸临床应用提供参考。  相似文献   
993.
目的 探讨急性胆管炎腹腔镜胆总管探查后一期缝合与T管引流两种手术方式的特点,评估其可行性与安全性.方法 回顾性分析首都医科大学宣武医院普外科2012年1月-2014年12月100例急性胆管炎患者行腹腔镜胆囊切除+胆总管探查术患者的临床资料,其中54例(54%)患者行一期缝合,46例(46%)患者行T管引流.结果 100例患者均成功行手术治疗,手术时间缝合组显著短于T管组(96.72 minvs123.00 min,P=0.001),术中出血量缝合组与T管组相比显著减少(27.13 mlvs38.48 ml,P=0.009).缝合组术后胃肠功能恢复时间(1.57 dvs2.33 d,P=0.003)与术后住院时间(6.19 dvs9.20d,P=0.000)均显著短于T管组.两组术后腹腔总引流量(309.22mlvs212.46ml,P=0.070),引流时间(3.96 dvs4.02 d,P=0.875),术后胆漏发病率(9.3% vs0,P=0.060),出血率(5.1%vs2.2%,P=0.622)差异均无统计学意义.结论 急性胆管炎腹腔镜胆总管探查后一期缝合严格掌握适应证后,与T管引流相比,同样安全有效.  相似文献   
994.
Interactions between monocytes/macrophages and endothelial cells play an important role in the pathogenesis of atherosclerosis, and the adherence of monocytes to the arterial endothelium is one of the early events in atherogenesis. In the present study, peritoneal macrophages harvested from green fluorescent protein (GFP) transgenic mice were used to analyze how Chlamydia pneumoniae infection affects the adherence of GFP-macrophages to mouse endothelial cells in vitro and to the aorta from normolipidemic and hyperlipidemic mice ex vivo. In vitro studies showed that C. pneumoniae-infected GFP-macrophages adhered better than uninfected macrophages to endothelial cells and GFP-macrophages adhered better to infected than uninfected endothelial cells. The ex vivo studies showed that C. pneumoniae-infected macrophages adhered better than uninfected macrophages to aortas from both normolipidemic and hyperlipidemic C57BL/6J mice and apolipoprotein E (ApoE)-deficient mice. In contrast, adherence of C. pneumoniae-infected macrophages to the aortas of intercellular adhesion molecule 1 (ICAM-1) knockout mice was not enhanced, suggesting that ICAM-1 is crucial for activation of the adherence of C. pneumoniae-infected macrophages to the endothelium. In conclusion, the present study defined a homing mechanism by which C. pneumoniae promotes the adherence of mononuclear phagocytes to the endothelium at the site of atherosclerotic lesion formation to promote the progression of atherosclerosis.  相似文献   
995.
Information about the effects of angiotensin II receptor blocker (ARB) therapy on the hemodynamic and cardiac structure in patients with chronic aortic regurgitation (CAR) and isolated systolic hypertension (ISH) is limited. This study planned to test the hypothesis that l -arginine could further enhance the beneficial effect of an ARB, losartan, and provide a favorable effect on the natural history of CAR and ISH. Sixty patients with CAR and ISH were enrolled in a randomized, double-blind trial comparing hemodynamic and ultrasonic change in two treatment arms: losartan +  l -arginine and losartan-only treated groups. Serial echocardiographic and hemodynamic studies were evaluated before and after treatment. Both groups had a significant reduction in systolic blood pressure (SBP) and diastolic blood pressure (DBP), left ventricular end-diastolic volume index (LVEDVI), LV end-systolic volume index (LVESVI), LV mass index (LVMI), and LV mean wall stress after 6- and 12-month treatment ( p <0.01 in all comparisons). Both groups had a significant increase in LV ejection fraction and exercise duration after 6- and 12-month treatment ( p  < 0.01 in all comparisons). Using multivariate linear regression analysis, only losartan +  l -arginine therapy achieved a significantly lower LVESVI (38.89 ± 0.23 mL/m 2 ), LVEDVI (102.3 ± 0.3 mL/m 2 ), LVMI (107.6 ± 0.3 g/m 2 ), SBP (123.5 ± 1.0 mm Hg), and greater exercise duration (7.38 ± 0.02 minutes) than those of the losartan-only treated groups ( p <0.01 in all comparisons). These findings suggest that early co-administrative strategy provides a beneficial approach to favorably influence the natural history of CAR.  相似文献   
996.

Genetic predispositions and environmental influences both play an important role in adolescent externalizing behavior; however, they are not always independent. To elucidate gene–environment interplay, we examined the interrelationships between externalizing polygenic risk scores, parental knowledge, and peer substance use in impacting adolescent externalizing behavior across two time-points in a high-risk longitudinal sample of 1,200 adolescents (764 European and 436 African ancestry; Mage = 12.99) from the Collaborative Study on the Genetics of Alcoholism. Results from multivariate path analysis indicated that externalizing polygenic scores were directly associated with adolescent externalizing behavior but also indirectly via peer substance use, in the European ancestry sample. No significant polygenic association nor indirect effects of genetic risk were observed in the African ancestry group, likely due to more limited power. Our findings underscore the importance of gene–environment interplay and suggest peer substance use may be a mechanism through which genetic risk influences adolescent externalizing behavior.

  相似文献   
997.
1. Tanshinone IIA is the main active diterpene quinone in the herbal medicine Salvia miltiorrhiza. In untreated mouse liver microsomes, tanshinone IIA selectively inhibited 7-ethoxyresorufin O -deethylation (EROD) and 7-methoxyresorufin O -demethylation (MROD) activities without affecting the oxidation of benzo(a)pyrene, tolbutamide, N -nitrosodimethylamine and nifedipine. Tanshinone IIA was a competitive inhibitor of MROD activity with a K i of 7.2 ± 0.7 nM. 2. In 3-methylcholanthrene-treated mouse liver microsomes, tanshinone IIA and two minor tanshinones, tanshinone I and cryptotanshinone, inhibited liver microsomal MROD activity without affecting EROD and benzo(a)pyrene hydroxylation activities at the concentrations up to 1 µ M. Tanshinone IIA induced a type I binding spectrum with a spectral dissociation constant K?s of 2.3 ± 0.8 µ M without cooperativity. 3. In human liver microsomes, tanshinone IIA decreased EROD and MROD activities without affecting the oxidation of benzo(a)pyrene, tolbutamide, chlorzoxazone and nifedipine. 4. In Escherichia coli membranes expressing bicistronic human CYP1A enzymes, tanshinone IIA inhibited EROD activity of CYP1A1 with an IC 50 48 times higher than that for CYP1A2. Tanshinone I and cryptotanshinone had the same IC 50 ratio (1A1/1A2) of 4. 5. The results indicate that tanshinone represents a new group of CYP1A inhibitors, and tanshinone IIA had the highest selectivity in inhibition of CYP1A2.  相似文献   
998.
OBJECTIVE--To compare Doppler, echocardiographic, and clinical variables in female and male patients with mitral stenosis. DESIGN--Observational study in consecutive patients with mitral stenosis of cross sectional and Doppler echocardiographic and clinical variables and a retrospective search for a history of systemic embolism. SETTING--A medical centre with 3000 beds, serving both urban and rural populations. PATIENTS--500 consecutive patients with an echocardiographic mitral valve area of 2 cm2 or less. 331 (66.2%) were female and 169 (33.8%) male (mean (SD) ages of 49 (13) and 48 (14) respectively). MAIN OUTCOME MEASURES--Mitral valve areas by echocardiographic planimetry and Doppler pressure half-time method, peak early diastolic mitral velocity and pressure gradient, echocardiographic score of mitral valve, left atrial end systolic diameter, frequency of left atrial thrombus and smoky echoes as well as various valve lesions detected with Doppler and echocardiography, cardiac rhythm, symptomatic functional class of heart failure, and history of systemic embolism. RESULTS--The prevalence of significant tricuspid (22% v 9%, P < 0.001) and pulmonary regurgitation (5% v 1%, P = 0.018) was higher in the female patients than in the male patients. Female patients also had a higher peak regurgitant velocity (3.2 (0.7) v 2.9 (0.7) m/s, P = 0.007) and pressure gradient (41 (21) v 36 (19) mm Hg, P = 0.010) across the tricuspid valve. However, the male patients had a higher echocardiographic score (9.7 (2.4) v 7.0 (2.3), P < 0.001) and a smaller Doppler-derived mitral valve area (0.9 (0.4) v 1.0 (0.4) cm2, P = 0.027). There were no differences between the female and the male patients in mitral valve area measured by planimetry, peak early diastolic mitral velocity and pressure gradient, and left atrial end systolic diameter or in the prevalence of atrial fibrillation, left atrial thrombus, left atrial smoky echoes, significant aortic stenosis, aortic regurgitation, or heart failure of New York Heart Association class III or IV. CONCLUSIONS--Female patients not only had a higher prevalence of mitral stenosis but also had a higher prevalence of associated tricuspid and pulmonary regurgitation along with a higher velocity and gradient of tricuspid regurgitation. The echocardiographic score was higher in male patients, however. These findings suggest that the pathophysiology of mitral stenosis is different in the two sexes and that gender should be taken into account when therapeutic strategies are formulated.  相似文献   
999.

Background and objectives

Fluid overload is a common characteristic associated with renal progression in CKD. Additionally, fluid overload is an independent predictor of all-cause or cardiovascular mortality in patients on dialysis, but its influence on patients not on dialysis is uncertain. The aim of the study was to assess the relationship between the severity of fluid status and clinical outcomes in an advanced CKD cohort.

Design, setting, participants, & measurements

In total, 478 predialysis patients with stages 4 and 5 CKD in the integrated CKD care program were enrolled from January of 2011 to December of 2011 and followed-up until August of 2013. The clinical outcomes included cardiovascular morbidity and all-cause mortality. The relative hydration status (overhydration/extracellular water) was used as the presentation of the severity of fluid status and measured using a body composition monitor. Overhydration/extracellular water >7% was defined as fluid overload.

Results

Over a median follow-up period of 23.2 (12.6–26.4) months, 66 (13.8%) patients reached all-cause mortality or cardiovascular morbidity. The adjusted hazard ratio of the combined outcome of all-cause mortality or cardiovascular morbidity for every 1% higher overhydration/extracellular water was 1.08 (95% confidence interval, 1.04 to 1.12; P<0.001). The adjusted overhydration/extracellular water for the combined outcome of all-cause mortality or cardiovascular morbidity in participants with overhydration/extracellular water ≥7% compared with those with overhydration/extracellular water <7% was 1.93 (95% confidence interval, 1.01 to 3.69; P=0.04). In subgroup analysis, higher overhydration/extracellular water was consistently associated with increased risk for the combined outcome independent of diabetes, cardiovascular disease, and serum albumin. There was no significant interaction between all subgroups.

Conclusions

These findings suggest that fluid overload is an independent risk factor of the combined outcome of all-cause mortality or cardiovascular morbidity in patients with advanced CKD.  相似文献   
1000.
目的 由于磁场会改变次级电子运动轨迹,继而影响剂量场分布,磁共振加速器(MR-Linac) X线束剂量学特性与常规加速器有差别。本项目旨在测量和分析1.5T MR-Linac的X线束剂量学特性。方法 中国医学科学院肿瘤医院于2019年5月安装1台瑞典医科达公司Unity型1.5T MR-Linac,使用磁场兼容工具对其进行测量,测量项目包括表面剂量、最大剂量点深度、射线质、离轴比曲线(OAR)中心位置、对称性、半影宽度、不同机架角度的输出量变化。结果 不同射野面积的平均表面剂量为40.48%,平均最大剂量点深度为1.25cm。10cm×10cm射野面积下,x轴方向的OAR中心位置往x2侧偏移1.47mm,对称性为101.33%,两侧半影宽度分别为6.86mm和7.14mm;y轴方向的OAR中心位置偏移0.3mm,对称性为100.85%,两侧半影宽度分别为5.92mm和5.95mm。不同机架角度下输出量最大偏差达1.50%。结论 与常规加速器不同,MR-Linac不同射野面积表面剂量数值趋于一致,最大剂量点深度上升。x轴方向的OAR中心位置往x2侧偏移,造成对称性变差和半影不对称。不同机架角度下的输出量变化明显,需要修正。  相似文献   
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