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991.
992.
The effects of propranolol and digoxin on the acute vascular responses to frusemide in normal man. 总被引:4,自引:4,他引:0 下载免费PDF全文
G D Johnston P C O''Connor D P Nicholls W J Leahey M B Finch 《British journal of clinical pharmacology》1985,19(4):417-421
To examine the importance of acute frusemide-induced renin release in the production of the acute peripheral venous and arterial responses to frusemide in man, the effects of two drugs, previously described as inhibitors of acute frusemide-induced renin release, propranolol and digoxin, were examined. Propranolol abolished the acute increases in venous capacitance and blood pressure and attenuated the increases in forearm vascular resistance produced by frusemide. The acute increases in plasma renin activity and plasma aldosterone concentrations were also abolished. Pre-treatment with digoxin had no effect on the acute peripheral vascular responses to frusemide and failed to inhibit the acute increases in plasma renin activity and plasma aldosterone produced by frusemide. The study provides further evidence of a relationship between acute frusemide-induced renin release and the acute peripheral vascular effects of frusemide in man. 相似文献
993.
994.
Loflin TG; Simeone JF; Mueller PR; Saini S; Stark DD; Butch RJ; Brady TJ; Ferrucci JT Jr 《Radiology》1985,157(2):457-459
Fifty-three samples of gallbladder bile were obtained at the time of cholecystectomy from patients with the clinical diagnosis of acute or chronic cholecystitis. Five bile samples from patients with clinically normal gallbladders also were obtained. Proton magnetic resonance (MR) relaxation times, protein content, and water content were determined for the bile samples, and the data were grouped according to pathologic diagnosis, which disclosed 11 cases of acute cholecystitis, 41 cases of chronic cholecystitis, and six normal gallbladders. There was no significant difference in the mean T1 and T2 values between the groups with acute and chronic cholecystitis. Patients with chronic cholecystitis were found to have more concentrated bile than those with acute cholecystitis. Protein content varied widely within both groups of patients. We conclude that T1 and T2 relaxation times do not reliably differentiate acute from chronic cholecystitis. 相似文献
995.
Cerebellopontine angle-petromastoid mass lesions: comparative study of diagnosis with MR imaging and CT 总被引:1,自引:0,他引:1
Capabilities of computed tomography (CT) and magnetic resonance (MR) imaging in the diagnosis of cerebellopontine angle-petromastoid (CPA-PM) lesions were compared in 75 patients. CT and MR demonstrated 95.8% and 98.7% of the lesions, respectively. MR was often more helpful for characterization of neuromas, epidermoid cysts, exophytic gliomas, and vascular lesions, while CT was usually more informative for meningiomas, metastases, and tympanomastoid cholesteatomas. A specific diagnosis could be made with MR for most types of lesions through use of relaxation parameters and characteristic morphologic changes. Size, shape, location, and contour of the lesions, however, were generally more helpful for differential diagnosis than relaxation times. With the exception of metastatic lesions, cholesteatomas, and some meningiomas, MR was usually more helpful than CT in defining the full extent of the lesions and their relationships to contiguous structures. MR, because of its high accuracy in lesion detection, characterization, and localization, is a suitable primary diagnostic modality for evaluating patients with suspected CPA-PM lesions. 相似文献
996.
997.
We report a retrospective study of 60 eyes from 46 patients all with primary open-angle glaucoma who had a trabeculectomy to one or both eyes. A minimum five-year follow-up was available. The percentage pressure reductions at the one and five years postoperatively is shown. In a subgroup of 50 eyes which had Goldman fields documented at least six-monthly for a minimum of five years postoperatively there was a continuation of glaucomatous field loss in 18% of eyes despite postoperative pressures in the normal range. The five-year percentage pressure reduction and the minimum percentage pressure reductions were statistically significant in a comparison between the field loss and no field loss groups. However, in the individual case there seemed no way of predicting which eyes would develop postoperative field loss, and regular postoperative perimetric assessment was found to be essential whatever the pressure measurements recorded. 相似文献
998.
999.
Mueller PR; Ferrucci JT Jr; Simeone JF; Butch RJ; Wittenberg J; White M; Brown AS 《Radiology》1985,155(3):615-618
Twelve abscesses and fluid collections in the lesser peritoneal sac were drained percutaneously using an access route across the intervening liver. This rather unusual access was chosen when other approaches were contraindicated because of surrounding colon, stomach, or spleen. All collections were drained successfully, and no specific complications such as hemorrhage, bile leak, or liver abscess occurred. Placement of an abscess drainage catheter should be done through the peripheral portion of the liver if possible. The technique offers a new, safe approach to percutaneous drainage of hitherto inaccessible collections. 相似文献
1000.
丁基苯酞对局部脑缺血大鼠神经元迟发性损伤及细胞内钙的影响 总被引:21,自引:2,他引:19
观察了丁基苯酞(NBP)对局部脑缺血迟发性脑梗塞和神经功能缺损的影响。结果表明,大鼠大脑中动脉阻断(MCAO)后2h分别poNBP80,160和240mg·kg-1,均能明显降低脑梗塞面积,抑制率分别为49.0%,69.5%及85.1%,并明显改善神经功能缺失。在MCAO前1h予防给NBP(160mg·kg-1po),也可明显缩小脑梗塞面积和改善神经功能缺失;在MCAO前连续口服7d,NBP剂量为80mg·kg-1·d-1,对上述指标均有改善作用。NBP对高K+引起大鼠脑突触体内Ca2+含量升高无影响。以上结果提示NBP对迟发性神经元损伤有保护作用。 相似文献