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Brachial artery hemodynamic response to acute converting enzyme inhibition by enalaprilat in essential hypertension 总被引:1,自引:0,他引:1
To assess the vascular involvement of renin-angiotensin system inhibition in human hypertension, acute effects of intravenous enalaprilat on brachial artery diameter, blood flow, and blood velocity were investigated in hypertensive patients by pulsed Doppler technique and compared with effects of saline vehicle. Compared with saline vehicle, enalaprilat reduced blood pressure (P less than 0.001) and increased brachial arterial diameter (P less than 0.01) and brachial blood flow (P less than 0.01). Enalaprilat effect on arterial pulse pressure was dependent on preinjection pulse pressure (r = -0.76; P less than 0.001), but its effect on mean blood pressure was not dependent on preinjection mean blood pressure. On the other hand, enalaprilat effect on arterial blood flow was negatively correlated with preinjection blood pressure (r = -0.64; P less than 0.02). The findings point to different responses of large and small arteries to intravenous enalaprilat. 相似文献
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Association of Hypoalbuminemia on the First Postoperative Day and Complications Following Esophagectomy 总被引:1,自引:0,他引:1
Aoife M. Ryan Aine Hearty Ruth S. Prichard Aileen Cunningham Suzanne P. Rowley John V. Reynolds 《Journal of gastrointestinal surgery》2007,11(10):1355-1360
Objective Changes in serum albumin may reflect systemic immunoinflammation and hypermetabolism in response to insults such as trauma
and sepsis. Esophagectomy is associated with a major metabolic stress, and the aim of this study was to determine if the absolute
albumin level on the first postoperative day was of value in predicting in-hospital complications.
Methods A retrospective study of 200 patients undergoing esophagectomy for malignant disease at St. James Hospital between 1999 and
2005 was performed. Patients who had pre and postoperative (days 1, 3, and 7) serum albumin levels measured were included
in the study. Patients were subdivided into three postoperative albumin categories <20 g/l, 20–25 g/l, >25 g/l. Logistic regression
analysis was performed to calculate the odds of morbidity and mortality according to the day 1 albumin level.
Results Patients with an albumin of less than 20 g/l on the first postoperative day were twice as likely to develop postoperative
complications than those with an albumin of greater than 20 g/l (54 vs 28% respectively, p < 0.011). Correspondingly, these patients also had a significantly higher rate of Adult Respiratory Distress Syndrome (22
vs 5%, p < 0.001), respiratory failure (27 vs 8%, p < 0.01) and in-hospital mortality (27 vs 6% (p < 0.001). On multivariate logistic regression analysis, day 1 albumin level was independently related to postoperative complications
(odds ratios, 0.89: 95%; confidence intervals, 0.83–0.96; p < 0.005). In addition, albumin <20 g/l on the first postoperative day was associated with the need for further surgery and
a return to ICU.
Conclusion Serum albumin concentration on the first postoperative day is a better predictor of surgical outcome than many other preoperative
risk factors. It is a low cost test that may be used as a prognostic tool to detect the risk of adverse surgical outcomes. 相似文献
5.
Kurt H. Chau George J. Dawson Khalif M. Bile Lars O. Magnius Maria H. Sjogren Isa K. Mushahwar 《Journal of medical virology》1993,40(4):334-338
A newly developed assay for IgA class antibody to hepatitis E virus (IgA anti-HEV) was used to study 145 serum samples collected during an outbreak of an enterically transmitted hepatitis that occurred in 3 villages in the lower Shebeli region of Southern Somalia between January, 1988 and November, 1989. A total of 52.4% of the afflicted patients were found positive for IgA anti-HEV, and 73.1% of these were also positive for IgM. Both antibodies disappeared during the convalescence period. Similar results were also seen in serum obtained from sporadic cases of acute waterborne hepatitis in Pakistan. © 1993 Wiley-Liss, Inc. 相似文献
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Evidence that [3H]-alpha,beta-methylene ATP may label an endothelial-derived cell line 5'-nucleotidase with high affinity. 总被引:1,自引:1,他引:0 下载免费PDF全文
A. D. Michel N. M. Chau T. P. Fan E. E. Frost P. P. Humphrey 《British journal of pharmacology》1995,115(5):767-774
1. In membranes prepared from a permanent cell line of endothelial origin (WEC cells), [3H]-alpha, beta-methylene ATP ([3H]-alpha, beta-meATP) labelled high (pKd = 9.5; Bmax = 3.75 pmol mg-1 protein) and low (pKd = 7.2; Bmax = 23.3 pmol mg-1 protein) affinity binding sites. The high affinity [3H]-alpha, beta-meATP binding sites in the WEC cell membranes could be selectively labelled with a low concentration of the radioligand (1 nM). In competition studies performed at a radioligand concentration of 1 nM, 88.6% of the sites possessed high affinity (pIC50 = 8.26) for alpha, beta-meATP. 2. The high affinity [3H]-alpha, beta-meATP binding sites appeared heterogeneous since in competition studies a number of nucleotide analogues (alpha, beta-meADP, ATP, ADP, AMP, GTP, GppNHp, GMP) and adenosine identified two populations of the sites labelled by 1 nM [3H]-alpha, beta-meATP. The proportion of sites with high affinity for these compounds was found to vary between 42 and 69%. 3. Approximately 60-69% of the binding sites labelled with 1 nM [3H]-alpha, beta-meATP possessed high affinity for alpha, beta-meADP (pIC50 = 8.87), AMP (pIC50 = 7.12), GMP (pIC50 = 7.34), UTP (pIC50 = 6.12), GTP (pIC50 = 7.59), GppNHp (pIC50 = 7.35) and adenosine (pIC50 = 5.45).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
7.
Thuy T. Chau Thomas Walter Alan Katz Barry M. Weichman 《Drug development research》1993,28(4):488-495
Pemedolac Na, 1-ethyl-1,3,4,9-tetrahydro-4-(phenylmethyl)-pyrano [3,4-b] indole-1-acetic acid sodium salt, exhibited equipotent analgesic effects after oral, iv, and im administration, suggesting that it is well absorbed. In mouse writhing models, the ED50 values ranged from 0.3 mg (0.81 μmol)/kg (vs. acetylcholine) to 4.3 mg (11.6 μmol)/kg (vs. paraphenylbenzoquinone [PBQ]). In the rat Randall-Selitto model, the ED50 o the compound was approximately 0.001 mg (2.7 nmol)/kg, with a flat dose response curve. The peak effects lasted for 7–9 h, 10–18 h, and 5 h following oral, im, and iv injections, respectively. Intracerebroventricular (i.c.v.) injections of pemedolac Na inhibited the PBQ-induced writing in mice with an ED50 of 43.5 μg (0.12 μmol)/mouse, and this effect was not antagonized by naloxone. It was inactive in the hot plate and tail flick tests, demonstrating that pemedolac Na does not act via an opiate mechanism. These results indicate that pemedolac Na is a viable parenteral and oral analgesic, typified by high analgesic potency, a rapid onset and long duration of action, and an extremely wide safety index. © Wiley-Liss, Inc. 相似文献
8.
Paired kidney analysis of tacrolimus and cyclosporine microemulsion-based therapy in Chinese cadaveric renal transplant recipients 总被引:5,自引:0,他引:5
Chi Yuen Cheung Kim Ming Wong Hoi Wong Chan Yan Lun Liu Yiu Han Chan Ho Sing Wong Wai Leung Chak Koon Shing Choi Ka Foon Chau Chun Sang Li 《Transplant international》2006,19(8):657-666
Few studies used paired kidneys for comparison between tacrolimus and cyclosporine in renal transplantation. Most of the published data used whole blood trough levels for drug monitoring. However, the use of limited sampling strategy and abbreviated formula to estimate the 12-h area under concentration-time curve (AUC(0-12)) allowed better prediction of drug exposure. Sixty-six first cadaveric renal transplant recipients receiving paired kidneys were randomized to receive either tacrolimus-based (n = 33) or cyclosporine microemulsion (Neoral)-based therapies (n = 33). Abbreviated AUC(0-12) was used for drug monitoring and dose titration. Mean follow-up duration was 2.8 +/- 2 years. The patient and graft survival were comparable. Fewer incidence of acute rejection was observed in tacrolimus group (15% vs. 27.3%) though the difference was not significant (P = 0.23). The absolute value and the rate of decline of creatinine clearance were both significantly better in tacrolimus-treated patients. Prevalence of hypertension, post-transplant diabetes mellitus, infection, and malignancy were similar in both groups. Prevalence of hypercholesterolemia (11/33 vs. 4/33) and gum hypertrophy (6/33 vs. 1/33) was more common in cyclosporine-treated patients (P = 0.04 in both parameters). This was the first prospective, randomized study with paired kidney analysis showing the renal function was significantly better in tacrolimus-treated patients than in cyclosporine-treated patients. 相似文献
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Frank P MacMaster Aileen Russell Yousha Mirza Matcheri S Keshavan S Preeya Banerjee Rashmi Bhandari Courtney Boyd Michelle Lynch Michelle Rose Jennifer Ivey Gregory J Moore David R Rosenberg 《Neuropsychopharmacology》2006,59(3):252-257
BACKGROUND: Abnormalities in the limbic-hypothalamic-pituitary-adrenal (LHPA) axis have been implicated in the pathogenesis of obsessive-compulsive disorder (OCD). To our knowledge, however, no prior study has measured pituitary gland volume in OCD. METHODS: Volumetric magnetic resonance imaging studies were conducted in 31 psychotropic drug-na?ve children (10 boys, 21 girls) aged 8-17 years and 31 case-matched healthy comparison subjects. RESULTS: Pituitary volume was significantly smaller in patients with OCD as compared with healthy control subjects (11% smaller). Smaller pituitary volume in patients with OCD was associated with increased compulsive but not obsessive symptom severity. Boys with OCD had smaller pituitary gland volumes compared with control boys (20% smaller). No significant differences in pituitary volume were observed between girls with OCD and control girls. Boys with OCD had significantly smaller pituitary volumes than girls with OCD (31% smaller), whereas control boys also had smaller pituitary gland volumes compared with control girls (21% smaller). CONCLUSIONS: These findings provide new evidence of reduced pituitary volume in pediatric OCD that seems to be more prominent in male patients. The observed alterations in pituitary volume are consistent with neuroendocrine studies that have reported abnormalities in the LHPA axis in OCD. 相似文献