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The effect of the combined ETA/ETB endothelin receptor antagonist bosentan on blood pressure, vascular hypertrophy, and pathologic renal changes was investigated in a model of malignant hypertension, severe vascular hypertrophy, and enhanced vascular expression of endothelin-1, the deoxycorticosterone acetate (DOCA), and salt-treated spontaneously hypertensive rat (SHR). DOCA-salt treated SHR received 100 mg bosentan per kilogram weight per day mixed with their food. Systolic blood pressure of untreated DOCA-salt SHR rose to 241 +/- 1.5 mm Hg, whereas that of bosentan-treated rats rose to 221 +/- 5.1 mm Hg (P < .01). Cardiac and conduit artery mass were not affected by treatment. Small arteries from the coronary, renal, and mesenteric circulations showed a smaller media width and cross-sectional area of the media in rats treated with bosentan than in untreated rats. The kidneys showed the presence of fibrinoid necrosis in a high percentage of afferent arterioles and glomeruli of untreated DOCA-SHR. Some kidneys of treated rats exhibited less severe vascular hypertrophy and lesser extent of vascular or glomerular fibrinoid necrosis, but the renal injury score of bosentan-treated DOCA-SHR was only at the limit of significance from that of untreated rats (P = .06). These results suggest a role for endothelin-1 in blood pressure elevation and the severe vascular hypertrophy of small arteries of the coronary, renal, and mesenteric vasculature, but not of the heart or larger conduit vessels in the malignant hypertension that SHR develop after treatment with DOCA and salt. Although some bosentan-treated rats showed fewer renal lesions, a significant effect on renal pathology could not be unambiguously demonstrated. Further studies will be necessary to determine whether endothelin antagonists may indeed offer some degree of renal protection and have therapeutic potential in severe or malignant hypertension. 相似文献
954.
M. EL ABBOUDI S. PANDIAN G. TREPANIER R.E. SIMARD B. H. LEE 《Journal of food science》1991,56(4):948-949
The aim of this study was to establish adequate conditions for heat-shocking cells of lactobacilli, to sufficiently suppress lactic acid production without damaging the proteolytic enzyme system important for cheese maturation. Three temperatures, 65, 67 and 70°C were tested, for 22 sec. The best combination for maximum retardation of lactic acid production and minimum damage to the proteolytic system was obtained by treating cells at 67°C for 22 sec. Following such treatment, lactic acid production was retarded by 24 hr, while the proteolytic enzyme system remained scarcely unchanged. 相似文献
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The treatment utility of the Sociotropy/Autonomy Scale was evaluated by matching or mismatching subjects to either individual or group cognitive therapy according to their dominant personality dimension. Both groups of subjects obtained statistically significant, but equivalent, reductions in depression. Consistent with Beck's (1983) interactional model, tests of clinical significance indicated a higher proportion of matched subjects who displayed marked improvement at follow-up. Implications for cognitive therapy and further research on the assessment of personality dimensions relevant to depression are discussed. 相似文献
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EL Clemens 《Canadian Metallurgical Quarterly》1995,20(4):254-261
Since the advent of diagnosis-related groups (DRGs), advocacy groups have claimed that although hospital discharge planners perceive the discharge planning process as helpful, elderly patients and their families do not. This article explores how the discharge planning process was perceived by 40 discharge planners and 40 family caregivers. Planners greatly overrated caregiver influence and the amount adequacy of information shared about posthospital health care, choice of discharge to home or nursing home, and time to decide. Caregivers perceived that nursing homes were forced on patients by social workers and physicians. DRGs, physicians, and hospital administrators appeared to pressure social workers to coerce mentally competent patients into nursing homes. Excessive concern by hospital staff about patient safety after discharge may override patients' rights to autonomy and self-determination, violating the NASW Code of Ethics. Implications for practice, policy, and future research are discussed. 相似文献
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