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排序方式: 共有1563条查询结果,搜索用时 15 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 Forty-seven percent of subjects (n = 916) were receiving antihypertensive therapy and 184 (20%) were withdrawn from therapy.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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D G Ray R Subramanyan T Titus J Tharakan J Joy C G Venkitachalam K G Balakrishnan 《International journal of cardiology》1992,36(3):273-281
Balloon angioplasty was performed in 46 patients (age 2-40 yr) with discrete native coarctation of aorta. Patients with associated patent ductus arteriosus, aberrant subclavian artery and aneurysms were excluded. The peak systolic gradient across the coarcted segment decreased from 52.1 +/- 18.5 mmHg to 18.6 +/- 14.8 mmHg (p less than 0.001), and the diameter of the coarcted segment increased from 3.6 +/- 1.7 mm/m2 to 9.1 +/- 3.2 mm/m2 (p less than 0.001). Follow-up haemodynamic and angiographic studies performed in 21 patients at 13.1 +/- 6.9 months after angioplasty, showed good results in 15 patients. Four patients undergoing haemodynamic study and 4 other patients undergoing noninvasive evaluation were graded as having bad results at follow-up. In 5 of these patients the poor results were due to primary failure of angioplasty in relieving the gradient, and three developed re-coarctation after initial fall in the trans-coarctation gradient. Four risk factors were identified on univariate analysis, which were associated with significantly larger residual gradients at follow-up: (1) size of isthmus/size of coarcted segment ratio less than 3.0; (2) size of post-coarctation descending aorta/size of isthmus ratio greater than 1.75; (3) size of coarcted segment after angioplasty/size of coarcted segment before angioplasty ratio less than 2.0; and (4) size of balloon/size of coarcted segment ratio less than 3.0. The presence of one or more risk factors was associated with bad late results. On multivariate analysis the ratio of balloon size/coarcted segment size was found to be the sole independent predictor of the late outcome (p less than 0.02).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Benefits of glucose and oxygen in multidose cold cardioplegia. 总被引:3,自引:0,他引:3
N E Doherty J F Turocy G A Geffin D D O'Keefe J S Titus W M Daggett 《The Journal of thoracic and cardiovascular surgery》1992,103(2):219-229
We tested the effects of glucose and oxygen in cardioplegic solutions on myocardial protection in the isolated perfused working rat heart. Recovery from 2 hours' hypothermic (8 degrees C) cardioplegic arrest was examined in 93 hearts. Cardioplegic solution, which was delivered every 15 minutes, was supplemented with glucose 28 mmol/L as a substrate or sucrose 28 mmol/L as a nonmetabolizable osmotic control; it was equilibrated with either 98% oxygen or 98% nitrogen, both with 2% carbon dioxide. Four combinations of hyperkalemic cardioplegic solution were studied: nitrogen-sucrose, nitrogen-glucose, oxygen-sucrose, and oxygen-glucose. During hypothermic arrest, oxygenation of cardioplegic solution greatly reduced myocardial lactate production and prevented ischemic contracture as indicated by coronary vascular resistance. Glucose increased lactate production modestly but significantly only when the cardioplegic solution was nitrogenated. Although end-arrest myocardial adenosine triphosphate and creatine phosphate were greatly increased by oxygenation of cardioplegic solution (p less than 0.005), we could not detect improved preservation of these high-energy phosphates by glucose. Averaged over reperfusion, percent recovery of cardiac output for the nitrogen-sucrose, nitrogen-glucose, oxygen-sucrose, and oxygen-glucose solutions was 32.3% +/- 6.1%, 45.9% +/- 4.6%, 44.5% +/- 4.6%, and 62.2% +/- 4.5%, respectively. Oxygenation of the glucose solution or addition of glucose to the oxygenated solution significantly improved recovery of cardiac output. The benefits of glucose and oxygen were additive, so that the oxygen-glucose cardioplegic solution provided the best functional recovery. We conclude that the addition of glucose to the fully oxygenated multidose cold cardioplegic solution improves functional recovery without increasing lactate production during arrest. 相似文献
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According to current research findings, women are more likely than men to suffer from depression, eating disorders, and multiple personality disorder. The authors review recent advances in the understanding of female psychology, family systems theory, and psychoanalytic theory to show how women's unique developmental challenges and complex social conditions interact to determine the form and expression of these disorders. After discussing contributing factors, the authors suggest appropriate approaches to diagnosis and treatment. They conclude that therapists of both genders must appreciate the complex causes of these disorders to be most helpful to their female patients. 相似文献
7.
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