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排序方式: 共有734条查询结果,搜索用时 31 毫秒
1.
CM Reid M. Nelson P. Beckinsale P. Ryan LMH Wing LJ Beilin MA Brown GLR Jennings CI Johnston J. Marley JJ McNeil TO Morgan J. Shaw ID Steven MJ West 《Clinical and experimental pharmacology & physiology》1997,24(5):370-373
1. The present study aimed to determine the feasibility of conducting a 5 year cardiovascular outcome trial of the treatment of 6000 elderly hypertensive patients in Australian general practices. 2. General practitioners (GPs) were invited to participate by mail and personal follow-up. Patient records were reviewed to identify subjects for a blood pressure (BP) screening programme. Blood pressure was measured on three occasions and eligible subjects were included if the average BP was 160 mmHg systolic or 90 mmHg diastolic if systolic BP was 140 mmHg. 3. Seven hundred and forty-one GPs were approached and 89 were enrolled in the study (12% of mail invites and 75% of those receiving a personal contact). In 16 practices where screening was completed, 82 000 records were reviewed to identify 4% patients eligible for screening. Twenty-two per cent of eligible subjects attended screening. Of 1938 subjects screened, 180 (9%) had BP 5=160/90 mmHg. Forty-seven percent of subjects (n = 916) were receiving antihypertensive therapy and 184 (20%) were withdrawn from therapy. One hundred and sixteen (63%) of these subjects had BP return to study entry levels within 6 weeks. Fifty-seven newly diagnosed and 81 previously treated subjects were randomized (7% of the screened population). 4. Based on the high participation rate of GPs, the response rate of patients to attend a BP screening programme and the 7% randomization to screening ratio for entry into the study, the ANBP2 pilot study has demonstrated that it is feasible to recruit subjects from Australian general practices to a cardiovascular outcome trial. 相似文献
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The effect of calcium supplement use on iron stores was examined in a randomized controlled study in free-living, healthy, premenopausal women. Of 109 women who completed the study, 52 were in the control group and 57 took two tablets containing 250 mg Ca as the carbonate with each of two meals daily for 12 wk. In all subjects at baseline, plasma ferritin concentrations were positively correlated with heme-iron intake (r = 0.21, P = 0.04), serum iron concentration (r = 0.19, P = 0.04), transferrin saturation (r = 0.31, P = 0.001), and hemoglobin concentration (r = 0.22, P = 0.02), and negatively correlated with total iron-binding capacity (TIBC, r = -0.42, P < 0.001). No significant differences in absolute or percent changes in plasma ferritin concentrations, serum iron concentrations, TIBC, transferrin saturation, hemoglobin concentrations, or hematocrit were observed between the treatment and control groups. Thus, over a 12-wk period, use of 1000 mg Ca as the carbonate daily with meals does not appear to be detrimental to iron stores in healthy, free-living, premenopausal women. 相似文献
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To establish a reference range, we measured intact parathyrin (parathyroid hormone, PTH) in 245 healthy postmenopausal women, ages 42-75 years, with use of the Allegro Intact PTH Kit from Nichols Institute Diagnostics. We also assayed serum from a subset of 120 of the women with kits specific for mid-molecule PTH. The mean intact PTH concentration for the 245 women was 32 ng/L (95% confidence interval 14-60 ng/L). Intact PTH values in these subjects were not normally distributed, although calcium concentrations in the same samples were. There was positive, but not significant (r = 0.12, P = 0.06), correlation between intact PTH and age, and a significant negative correlation between serum calcium and intact PTH that was not observed between calcium and mid-molecule PTH. The improved sensitivity of the intact PTH assay makes it useful in studies of calcium homeostasis in the normal population. 相似文献
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BACKGROUND: The recent introduction of urea sensors for dialysis monitoring
has made possible new approaches to urea kinetic modelling. In this study
we show how the equilibrated postdialysis urea concentration (Ceq) and Kt/V
corrected for double-pool urea kinetics (Kt/Vdp) can be accurately
determined using an on-line sensor providing a continuous measure of blood
water urea. A modification of the Smye constant volume double-pool theory
led to the following equations for Ceq and Kt/Vdp [formula: see text] where
Cpre is the blood concentration measured at the start of dialysis, t is the
length of the dialysis session (in min) and S(ex) is the constant slope of
the blood urea logarithm concentration decline following development of the
intercompartmental urea concentration gradient in the first 30-60 min of
dialysis. METHODS: These equations were tested in 11 patients undergoing
165-240 min of paired filtration dialysis with continuous monitoring of
blood urea concentration. Cpre was determined as the plateau concentration
during a preliminary period of 15-20 min of slow isolated ultrafiltration.
S(ex) was accurately determined from linear regression applied to the urea
sensor data from the 80-min point to the end of dialysis. RESULTS: Ceq and
Kt/Vdp determined from the above equations compared closely to values
determined from 25-40 min of urea rebound monitoring with the urea sensor:
10.6 +/- 3.0 versus 10.8 +/- 2.7 mmol/l (mean +/- SD) for Ceq and 1.21 +/-
0.24 versus 1.18 +/- 0.20 for Kt/Vdp, compared to single-pool values of
Kt/V = 1.34 +/- 0.23. CONCLUSION: This technique may be readily programmed
into on-line urea monitors to provide current and extrapolated values of
Ceq and Kt/Vdp from about the first hour of dialysis.
相似文献
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Zhao P Qin ZL Ke JS Lu Y Liu M Pan W Zhao LJ Cao J Qi ZT 《第二军医大学学报》2005,26(10):1167-1167
SARS-CoV isa newly identified coronavirus that causes severe acute respiratory syndrome (SARS). Currently, there is no effective method available for prophylaxis and treatment of SARS-CoVinfections. In the present study, the influence of small interfering RNA (siRNA) on SARS-CoV nucleocapsid (N) protein expression was detected in cultured cells and mouse muscles. Four siRNA expression cassettes driven by mouse U6 promoter targeting SARS-CoV N gene were prepared, and their inhibitory effects on expression of N and enhanced green fluorescence protein (EGFP) fusion protein were observed. 相似文献
10.
溴莫尼定对视网膜缺血性损伤神经保护作用的实验研究 总被引:1,自引:1,他引:0
目的:探讨溴莫尼定(brimonidine)对视网膜缺血性损伤神经的保护作用。方法:新西兰大耳白兔32只,随机分为正常对照组、生理盐水治疗组、噻吗心安(timolol)治疗组、brimonidine治疗组,每组8只。后3组为损伤治疗组,通过生理盐水前房高压灌注的方法,制成视网膜缺血动物模型,在视网膜缺血前lh其结膜囊内分剐给予生理盐水、0.5%timolol眼液或0.2%brimonidine眼液局部治疗。在灌注后7d,观察图形视网膜电图(P-ERG)b波振幅变化,并进行组织形态学观察和视网膜神经节细胞(RGC)计数分析。结果:灌注后7d,3个损伤治疗组相对b波振幅恢复率为:7%、11%和64%,RGC标准丢失率为:43%、38%和12%,brimori-die治疗组视网膜组织形态结构接近正常对照组,而生理盐水治疗组和timolol治疗组视网膜内层组织结构损伤明显。结论:Brimonidine局部治疗对缺血诱导的视网膜结构和功能的损害有明显的神经保护作用。 相似文献