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1.
目的 观察不同剂量蛇床子素对OPG基因敲除小鼠和去卵巢骨质疏松大鼠的影响。方法 选择3种不同剂量的蛇床子素作用于OPG基因敲除小鼠和去卵巢骨质疏松大鼠,以双能X骨密度仪检测动物全身骨密度的变化;将动物腰椎做硬组织切片,并进行骨形态计量学分析其骨小梁的变化。结果 对于OPG基因敲除小鼠,蛇床子素能提高其全身BMD,以中剂量(10mg/(kg?d))组提高最为明显,低剂量(5mg/(kg?d))次之,而高剂量(15mg/(kg?d))组效果最差。蛇床子素能提高OPG基因敲除小鼠腰椎骨小梁体积分数,增加骨小梁数目,增加骨小梁厚度,降低骨小梁分离度,其中以5mg/(kg?d)组作用最明显,其次为10mg/(kg?d)组,而15mg/(kg?d)组则效果最差;对于去卵巢骨质疏松大鼠,不同剂量的蛇床子素均能显著提高大鼠全身BMD,其中以中剂量(100mg/(kg?d))组为最佳。蛇床子素能显著提高大鼠腰椎骨小梁体积分数,以100mg/(kg?d)组最明显。显著增加大鼠腰椎骨小梁数目,以75mg/(kg?d)组最明显。蛇床子素100mg/(kg?d)组能增加大鼠腰椎骨小梁厚度。不同剂量的蛇床子素均能显著降低大鼠腰椎骨小梁分离度,其中以75mg/(kg?d)组和100mg/(kg?d)组最明显。结论 蛇床子素能促进骨形成,抑制骨吸收,从而起到抗骨质疏松的作用,其疗效与给药剂量密切相关。  相似文献   
2.

Background

Surgeon's performance is tracked using patient outcomes databases. We compared data on patients undergoing laparoscopic cholecystectomy from 2 large databases with significant institutional overlap to see if either patient characteristics or outcomes were similar enough to accurately compare performance.

Methods

Data from 2009 to 2011 were collected from University HealthSystem Consortium (UHC) and National Surgical Quality Improvement Program (NSQIP). UHC and NSQIP collect data from over 200 and 400 medical centers, respectively, with an overlap of 70. Patient demographics, pre-existing medical conditions, operative details, and outcomes were compared.

Results

Fifty-six thousand one hundred ninety-seven UHC patients and 56,197 NSQIP patients met criteria. Groups were matched by age, sex, and pre-existing comorbidities. Outcomes for NSQIP and UHC differed, including mortality (.20% NSQIP vs .12% UHC; P < .0001), morbidity (2.0% vs 1.5%; P < .0001), wound infection (.07% vs .33%; P < .0001), pneumonia (.38% vs .75%; P < .0001), urinary tract infections (.62% vs .01%; P < .0001), and length of hospital stay (1.8 ± 7.5 vs 3.8 ± 3.7 days; P = .0004), respectively.

Conclusions

Surgical outcomes are significantly different between databases and resulting performance data may be significantly biased. A single unified national database may be required to correct this problem.  相似文献   
3.
Quantitative assessment of fetal heart function has been difficult. Increasingly, tissue Doppler imaging (TDI) is used to measure fetal cardiac function noninvasively. There are two principal techniques, spectral pulsed wave (PW) TDI and color TDI (CTDI). Published reference values for fetal myocardial velocities are based on spectral PW TDI only. However, previous phantom, adult, and animal studies have shown that PW TDI velocities are systematically higher than CTDI velocities. There are no fetal studies so far. We hypothesized that myocardial velocities derived by PW TDI and CTDI are significantly different in the fetus. This prospective observational study included 91 fetuses (gestational age 28.6 ± 6.6 weeks; range 19–40 weeks) seen for routine prenatal ultrasound. From apical 4‐chamber views, tricuspid ring (right ventricle), lateral and septal mitral ring were sampled by PW TDI and CTDI. Bland–Altman analysis was used for comparisons. PW and CTDI S′ velocities correlated strongly in all three cardiac segments (r = 0.6 to 0.9; P < 0.01). There was a systematic bias toward higher velocities with PW TDI versus CTDI (bias 0.96 cm/s; 95% CI 1.08–0.85 cm/s). However, the strength of the correlation and bias varied depending on the region of the fetal heart sampled. PW TDI and CTDI velocity measurements are feasible in the fetus and correlate well. However, PW TDI velocities are higher than CTDI velocities with significant regional variation. This precludes a mathematical conversion of PW to CTDI in vivo. As PW TDI and color TDI vary, different reference values for fetal CTDI velocities were generated.  相似文献   
4.
目的观测犬心心腔主要结构,为心脏比较解剖学积累一定的资料。方法10%甲醛固定犬心45例,一周后解剖并观测二尖瓣复合体、三尖瓣复合体、肺动脉瓣环、主动脉瓣环、肺静脉、前后腔静脉、冠状窦和卵圆窝,统计学处理后与人的心脏进行比较分析。结果①犬心左心室呈圆锥形,分为左心室流入道及左心室流出道,其流入道主要结构为二尖瓣复合体。二尖瓣环周径为49.16±10.00mm,腱索总数为16.72±2.76条。左心室流出道主要结构为主动脉瓣、主动脉窦、主动脉口。主动脉瓣环周径为34.55±8.00mm;②犬心右心室主要结构有三尖瓣复合体、肺动脉瓣、假腱索、隔缘肉柱等。三尖瓣环周径为71.03±14.02mm,肺动脉瓣环周径为35.97±8.17mm;③犬心左右心房的主要结构有前后腔静脉、肺静脉、冠状窦和卵圆窝。前腔、后腔静脉口径分别为43.91±10.17mm、37.67±10.54mm。肺静脉平均为29.44±12.71mm。冠状窦口径平均为14.12±4.00mm。其中冠状窦口呈圆形的占89.7%,唇形的占10.3%。卵圆窝发现率为100%。结论犬心的主要结构与人类相似,但大小及假腱索、腱索总数有一定差异。  相似文献   
5.
目的:比较桡骨远端(斜)T形接骨板内固定和外固定架两种方法治疗桡骨远端不稳定性骨折的效果.方法:对2006年6月~2010年12月间的不稳定型骨折68例进行分析,其中45例分别使用接骨板内固定(26例)和外固定架治疗(19例)比较不同固定方法之间Gartland和Werley功能评分优艮率.结果:随访6~28个月,平均...  相似文献   
6.
Background: Poor arithmetic performance is among the most sensitive outcomes associated with prenatal alcohol exposure and is also common in individuals with attention‐deficit hyperactivity disorder (ADHD). We hypothesized that prenatal alcohol exposure would be associated with deficits in the most fundamental aspects of number processing, representation of quantity and distance, whereas ADHD would be associated with deficits in calculation, the form of number processing most dependent on attention and memory. Methods: Two hundred and sixty‐two inner‐city, African American adolescents, who had been evaluated prospectively for prenatal alcohol exposure and ADHD, were assessed on a number‐processing test comprised of 7 subtests. Results: More heavily alcohol‐exposed adolescents were 4 times more likely to meet diagnostic criteria for ADHD than those whose mothers abstained from alcohol use during pregnancy. Two dimensions of number processing were identified in a factor analysis—magnitude comparison and calculation. As hypothesized, prenatal alcohol exposure was more strongly related to the former and ADHD to the latter. Moreover, the relation of prenatal alcohol to calculation was fully mediated by magnitude comparison, whereas the relation of ADHD to calculation was mediated by IQ but not by magnitude comparison. Conclusion: These data confirm findings from previous studies identifying arithmetic as a particularly sensitive developmental endpoint for prenatal alcohol exposure. Whereas difficulties with arithmetic in ADHD are mediated by domain‐general deficits in overall cognitive ability, fetal alcohol‐related arithmetic difficulties are mediated primarily by a specific deficit in the core quantity system involving the ability to mentally represent and manipulate number. These data suggest that different interventions are likely to be effective for remediating arithmetic problems in children with prenatal alcohol exposure than in non‐exposed children with ADHD.  相似文献   
7.
ObjectiveTo assess whether survival differences exist between patients undergoing immediate open repair vs surveillance with selective repair for 4.0- to 5.4-cm abdominal aortic aneurysms (AAAs) and whether these differences vary by diameter, within sexes, or overall.Patients and MethodsThe study cohort included 2226 patients randomized to immediate repair or surveillance for the UK Small Aneurysm Trial (September 1, 1991, through July 31, 1998; follow-up, 2.6-6.9 years) or the Aneurysm Detection and Management trial (August 1, 1992, through July 31, 2000; follow-up, 3.5-8.0 years). Survival differences were assessed with proportional hazard models, adjusted for a comprehensive array of clinical and nonclinical risk factors. Interaction between treatment and AAA size was added to the model to assess whether the effect of immediate open repair vs surveillance varied by AAA size.ResultsThe adjusted analysis revealed no statistically significant survival difference between immediate open repair and surveillance patients (hazard ratio [HR], 0.99; 95% CI, 0.83-1.18; mean follow-up time, 1921 days for both study groups). This lack of treatment effect persisted when men (HR, 1.01; 95% CI, 0.84-1.21) and women (HR, 0.96; 95% CI, 0.49-1.86) were examined separately and did not vary by AAA size (P=.39 for the entire cohort and P=.24 for women).ConclusionImmediate open repair offered no significant survival benefit, even in patients with the largest AAAs and highest risk of rupture. Because recent trials failed to find a survival benefit of immediate endovascular repair over surveillance for small asymptomatic AAAs, our findings suggest that the gray area of first-line management for these patients should be resolved in favor of surveillance.  相似文献   
8.
东梅 《天津护理》2009,17(1):44-45
目的:探讨应用微机网络对护理工作的影响。方法:分别记录应用微机网络前后工作量基本相同的各30天的部分处理护理工作的时间,进行比较分析。结果:应用微机网络后部分处理护理工作时间明显缩短,与应用微机网络前相比,差异有显著性(P〈0.001)。结论:微机网络的应用大大节约了护理资源,提高了护士工作效率和护理工作质量。  相似文献   
9.
目的 比较阴性法CT胰胆管造影(nCTCP)与磁共振胰胆管造影(MRCP)在胆系梗阻疾病的诊断作用.方法 55例经临床确诊的胆系梗阻病例予以回顾性分析,其中12例作过胆囊切除术.采用多层螺旋CT平扫、增强双期扫描.以门脉期数据经重组分别获得2D多平面重组像及厚块最小强度投影(MinIP)nCTCP像.2D磁共振(MR)成像采用T1WI、T2WI扫描序列;MRCP采用2D厚块SSFSE序列,以最大强度投影(MIP)显示胰胆管结构.应用5°评分法评价2种方法对胆管显示能力及胆囊、胆囊管和胰管显示率;对照临床诊断结果,就2种方法判别梗阻部位和性质作出比较.结果 nCTCP对胆管显示能力平均为4.46°(2°~5°),胆囊、胆囊管和胰管显示率分别为97.7%(42/43)、62.8%(27/43)及87.3%(48/55),MRCP相应为4.52°(2°~5°)、86.0%(37/43)、60.5%(26/43)和92.7%(51/55),两组间差异均无统计学意义(P值均>0.05).2种方法同时发现14例肝内胆管变异、3例胆囊管残留;MRCP另见4例胰管变异,nCTCP为3例.定位准确度2种方法均为100%(55/55).nCTCP定性准确度为87.3%(48/55),MRCP为83.6%(46/55);结合2D像,二者分别为94.5%(52/55)、94.5%(52/55).结论 nCTCP、MRCP对胆系梗阻性疾病的诊断具有相近的效果,nCTCP可以作为MRCP检查的一种有效补充技术.2种方法结合2D像,不仅有助于提高定性诊断准确度,而且能提供临床更充分的参考信息.  相似文献   
10.
This article is one of a two part series examining the people and environment associated with patient handling. The approach used was that of an occupational injury investigation of a job class, which incorporates defining in the task, environment, tools, and worker health status. Hence, the objective of this portion of the research was to develop a method and use it to compare the physical and mental health of Alabama nurses with known normative populations to determine a baseline of overall health. For this purpose, the validated SF-36© survey was used to collect data on Alabama nurses who had been registered in the state for at least one year. The potential participant pool included 1000 nurses randomly selected from more than 49,000 registered. Physical mailers with a pre-paid return envelope and a follow-up reminder post-card were used. A return rate of 10% was expected based on nursing literature. One hundred and one surveys were returned with 87 being complete. Results confirmed that nursing in the US is a female dominated profession with the survey matching both the Alabama and US national average of 92%. Comparisons of the sample data to general populations yielded significant differences in 3 of the 8 outcome measures: social functioning; physical functioning; bodily pain. In each of these measures, Alabama nurses had a reduced health status compared to at least one comparative population. Additionally, data related to body mass index (BMI) for Alabama nurses were stratified by gender and age. Results indicated 28% had a “healthy” BMI with 37% and 35% of the nurses being “overweight” or “obese”, respectively. Consequently, results suggest Alabama nurses have a reduced health status compared to normative populations and show similar but not identical BMI trends to the general populations for the state of Alabama and the US, which warrants concerns about potential declines in health status among caregivers.

Significance to healthcare

Nurses constitute the largest proportion of the healthcare industry’s workforce. Understanding the perceptions of health status of this employee group is essential to gain further information about possible influences of health on nurses’ ability to continue to perform their jobs.  相似文献   
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