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101.
Checking catecholamine stability in whole blood, plasma, and platelets, we found that specimens stored at room temperature or frozen for periods ranging from 1.5 h to three weeks show no significant difference in measured catecholamine concentration. The implications of these findings are discussed. 相似文献
102.
Medical schools put little emphasis upon education on public health, even though public health has played an important role in this century. One way to harness its benefit in order to improve global health in the 21st century is to globally share lectures on public health through the Internet. We have developed the Supercourse comprising of web-based learning modules on epidemiology in a standardized format with the size of each web page less than 10 kilobytes. A cross-sectional observational study was conducted to investigate the association of the perception of the access speed to Web-based lectures by teachers with their perception of lecture quality. There were 223 teachers who rated the lectures: 72% were from North America or Western Europe, 40% had taught epidemiology, and 14% reported that the speed of access was slow. Odds ratio of above-average rating among those who reported that the speed of access was fast relative to those who reported that the speed of access was slow was 4.25 (2.03-8.91; P = 0.001). The odds ratios were similar and significant after taking into account several other factors, including the variation of rating across lectures, region, and experiences in teaching epidemiology. The results indicate that the perception of the quality of Web-based lectures is related to the speed of access to a web page. The speed of access may be as important, if not more important, as the content itself. This suggests that, to share educational materials on the Web globally for teachers, one must consider not only the content, but also how people at local sites gain access to the Internet. 相似文献
103.
A systems approach was employed to improve results of the single-contrast barium enema examination for detection of colonic polyps. Improvements were made in each of the following areas: radiographic-fluoroscopic equipment, fluoroscopic-television images, screen-film combinations, barium suspensions, examination techniques, imaging sequences, and quality controls. Radiologic-endoscopic correlation was undertaken for 137 colonic polyps seen endoscopically in 91 patients. The average age of the patients was 69 years. The sensitivity of the single-contrast examination for detection of all polyps was 80%. Polyps 5-9 mm in size were detected with 66% sensitivity, while 94% of polyps 10 mm or larger were detected. The results indicate that the sensitivity of a suitably performed single-contrast barium enema examination may approach that of the double-contrast study for the detection of colonic polyps, even in an elderly and infirm patient population. 相似文献
104.
To test the feasibility of teleradiology for use with excretory urograms obtained in the emergency department in cases for suspected renal colic, radiographs from 43 patients were digitized, transmitted via standard phone lines, and viewed on a video monitor 2 miles distant. Diagnostic interpretations of the video image and the original radiograph were reviewed for degree of concordance. The video and film images of the 27 examinations showing obstruction were interpreted with 100% correlation. Agreement as to the site of obstruction was present in 93% of cases. Only two-thirds of renal and ureteral calculi seen on the radiographs were discerned on the video images, however. Teleradiology proved as useful for ongoing monitoring and modification of these examinations as for initial interpretation. 相似文献
105.
So then, another year, but the same old desires revived indeed.Rather than take a Latin text as a point of departure for thiseditorial, as has been my past habit [1], I have chosen to considerthe Rubaiyat of Omar Khayyam, here in its most famous Englishtranslation, that of Edward Fitzgerald. The 11th century Persian scholar, Omar Khayyam, who we todayremember mostly as the poet author of the quatrains, was during 相似文献
106.
107.
Accuracy of dual-energy radiographic absorptiometry of the lumbar spine: cadaver study 总被引:1,自引:0,他引:1
Dual-energy radiographic absorptiometry (DRA) was used to measure the bone mineral content and area density of lumbar vertebrae (L2-L3) in 11 cadavers. These data were subsequently compared with measured ash content and density. Excellent correlation was obtained between bone mineral content measured with DRA and ash weight (r = .963, P less than .0001). The accuracy error in determining mineral content in lumbar vertebrae with DRA was about 9%. In addition, strong correlation was observed between bone mineral density measured with DRA and ash density (r = .881, P less than .0001). 相似文献
108.
目的:观察蜂胶乔松素对脂多糖诱导人脐静脉内皮细胞的影响,探讨其对人脐静脉内皮细胞可能的保护作用。方法:实验于2006-03/10在泰山医学院生命科学研究所(省重点实验室)完成。①实验材料:取出生1h内新生儿脐带,患者知情同意。②实验分组及方法:培养人脐静脉内皮细胞,建立脂多糖损伤模型(以10mg/L的脂多糖培养液培养细胞12h),实验分为空白对照组(加等量D-Hank’s液)、脂多糖组(10mg/L)、乔松素组(加10mg/L脂多糖预孵育12h后,按50,100,200mg/L分别加入乔松素),各组设8个复孔,共同孵育24h。③实验评估:光镜下观察细胞形态,MTT法观察乔松素对人脐静脉内皮细胞活性的影响,ELISA方法检测培养上清中血管假血友病因子的含量,TUNEL检测细胞凋亡率。结果:①细胞形态:空白对照组细胞紧密贴壁,呈铺路石状生长。脂多糖组可见多数细胞呈圆形;乔松素组见上述细胞较脂多糖组明显减少。②乔松素对人脐静脉内皮细胞活性、凋亡及血管假血友病因子含量的影响:与对照组比较,脂多糖组能明显诱导人脐静脉内皮细胞的凋亡(P<0.01),不同浓度乔松素组可改善内皮细胞形态,组织活性明显升高(P<0.05),同时抑制内皮细胞血管假血友病因子的释放(P<0.05),使脂多糖诱导的人脐静脉内皮细胞凋亡细胞数明显减少(P<0.05)。结论:乔松素能增强人脐静脉内皮细胞活性,抑制脂多糖诱导人脐静脉内皮细胞的凋亡,从而发挥可能的内皮细胞保护功能。 相似文献
109.
Betteridge DJ 《International journal of clinical practice》1999,53(4):243-250
An international multicentre double-blind randomised trial compared the efficacy and safety of cerivastatin (0.025, 0.05, 0.1 and 0.2 mg once daily) with placebo and simvastatin (20 mg) over a period of 12 weeks, with study extensions to 52 and 100 weeks. The primary efficacy parameter was the percentage change in low density lipoprotein cholesterol (LDL-C). This was reduced from the baseline by 12.5% (0.025 mg) to 30.6% (0.2 mg) compared with falls of 2.0% on placebo and 40.3% on simvastatin. All four cerivastatin doses and simvastatin (20 mg) produced significantly greater falls than placebo (p < 0.0001) and the decrease in LDL-C was dose-dependent for cerivastatin. Simvastatin produced significantly greater falls than any cerivastatin dose or placebo (p < 0.0001). The effect was maintained at 1 year but somewhat attenuated at 100 weeks. Significant falls were also seen in serum total cholesterol and triglycerides. High density lipoprotein cholesterol (HDL-C) levels were significantly increased by cerivastatin (0.1 and 0.2 mg) and simvastatin (20 mg) at 12 weeks and increased further by 100 weeks. Mean fasting apolipoprotein A1 and lipoprotein A1 were increased and apolipoprotein B decreased by cerivastatin and simvastatin therapy. All doses of cerivastatin produced significant falls in the total cholesterol/HDL-C ratio at 12 weeks (0.5-1.6) compared with a fall of 2.1 for simvastatin (20 mg). Cerivastatin was well tolerated. Elevations in creatine phosphokinase, aspartate aminotransferase and alanine aminotransferase were mostly minor and transitory. Vital signs, electrocardiogram determinations, urinalysis and ophthalmic assessment showed similar results for both drugs. Cerivastatin, at doses of 0.1 mg and 0.2 mg daily, is considered to be of therapeutic value in the treatment of patients with primary hypercholesterolaemia, with 0.2 mg cerivastatin achieving reductions of LDL-C and total cholesterol similar to those achieved in the WOSCOP and CARE studies. 相似文献
110.
Non-invasive trigeminal evoked potentials: normative aging data 总被引:1,自引:0,他引:1
J Polich DJ Dalessio M Aung M DeYarman 《Cephalalgia : an international journal of headache》1995,15(2):147-151
A mild electric shock applied to the lower lip was used to elicit reliable evoked potentials from the trigeminal nerve in 50 normal adults who ranged in age from 20 to 69 years. The waveforms were morphologically similar to those observed with invasive procedures. No substantial effects for subject age, side of stimulation, or recording electrode were obtained for any of the individual trigeminal evoked potential amplitudes or latencies. Female subjects tended to have somewhat larger amplitudes and shorter latencies than male subjects. The results suggest that non-invasive procedures produce reliable evoked potential measures of trigeminal nerve function for patients of all ages. 相似文献