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排序方式: 共有1492条查询结果,搜索用时 0 毫秒
1.
Coronary artery bypass grafts: visualization with MR imaging 总被引:1,自引:0,他引:1
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D. Chemla P. Démolis M. Thyrault D. Annane Y. Lecarpentier and JF Giudicelli 《Fundamental & clinical pharmacology》1996,10(4):393-399
Summary— The influence of local resistance and cardiac performance on peripheral blood acceleration was investigated in 14 healthy male volunteers. Steady and pulsatile flow was studied in the brachial and in the common carotid arteries, ie, two territories that exhibit marked differences in resistive characteristics. Instantaneous blood velocity (V), mean blood velocity (Vm ) and artery diameter (D) were evaluated at rest by an ultrasonic range-gated pulsed Doppler flowmeter using a double transducer probe, thus allowing the calculation of mean blood flow (Q). Mean local resistance (R) was obtained by dividing the mean arterial pressure by Q. The peak value of the local acceleration of the blood was obtained by computer-assisted calculation of the first derivative of instantaneous blood velocity (Gmax = +dV/dtmax ). Peak aortic blood acceleration (GAo) was simultaneously measured from the suprasternal notch using a pulsed Doppler velocity meter. In the brachial and the common carotid arteries, Gmax was of a similar magnitude (551 ±30 and 555 ± 44 cm/s2 , respectively) despite major differences in the respective D, Vm , Q and R values. In neither artery was there a relationship between Gmax and either resting Q or R. At the brachial artery level, Gmax was positively related to GAo ( r = 0.79, P = 0.0008). At the common carotid artery level, there was a weak, although non significant relationship between Gmax and GAo ( P = 0.08). Our results indicate that the local acceleration of peripheral blood flow in the brachial artery is related rather to upstream central impulse than to downstream hemodynamics, and suggest some regional differences in the hemodynamic determinants of the local acceleration of peripheral blood flow. 相似文献
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M N Levine J Hirsh M Gent A G Turpie J Leclerc P J Powers R M Jay J Neemeh 《Annals of internal medicine》1991,114(7):545-551
OBJECTIVE: To determine the relative efficacy and safety of low molecular weight (LMW) heparin (Enoxaparin) compared with standard calcium heparin for the prevention of postoperative deep vein thrombosis in patients undergoing elective hip surgery. DESIGN: A double-blind, randomized, controlled trial. PATIENTS: Six hundred sixty-five consecutive patients undergoing hip replacement at five participating hospitals. INTERVENTIONS: Patients received either fixed-dose LMW heparin, 30 mg subcutaneously twice daily, or fixed-dose standard calcium heparin, 7500 units subcutaneously twice daily; both regimens were started 12 to 24 hours after surgery and continued for 14 days or until discharge if sooner. MEASUREMENTS: All patients had postoperative I-125-fibrinogen leg scanning and impedance plethysmography. If results of one or both tests were positive, then venography was done. Otherwise, venography was done between day 10 and day 14, or sooner if the patient was ready for discharge. RESULTS: Evaluable venograms were obtained in 258 of the 333 patients randomly assigned to receive LMW heparin and in 263 of the 332 patients assigned to receive calcium heparin. For patients with evaluable venograms, thrombosis was detected in 50 patients (19.4%) who received LMW heparin compared with 61 patients (23.2%) who received standard heparin (difference, -3.8%; 95% CI, -11.1% to 3.6%) (P greater than 0.2). Proximal deep vein thrombosis was detected in 5.4% of the patients receiving LMW heparin and in 6.5% of the patients receiving standard heparin (difference, -1.1%; CI, - 5.2% to 3.3%) (P greater than 0.2). For the entire group of 665 patients, venous thrombosis occurred in 17.1% given LMW heparin and in 19.0% given standard heparin. Hemorrhagic complications occurred in 31 patients (9.3%) given standard heparin and in 17 patients (5.1%) given LMW heparin (difference, 4.2%; CI, 0.3% to 8.2%) (P = 0.035). The relative risk reduction was 45%. The rate of major bleeding in the standard heparin group was 5.7% compared with 3.3% in the LMW heparin group (difference, 2.4%; CI, -1.0% to 5.4%) (P = 0.13). The relative risk reduction was 42%. CONCLUSION: Low molecular weight heparin is significantly less hemorrhagic than standard unfractionated heparin; the difference in the rate of deep vein thrombosis, although not statistically significant (P greater than 0.2), favors the use of LMW heparin. 相似文献
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Between 1981-88, 223 surgical interventions were performed in cases of pathologic breast secretion after exclusion of extra-mammary aetiology. The milk duct was identified by pre-operative chromogalactography, followed by a selective excision of the ductal-lobular unit. In 36 cases (16.1%), however, neither spontaneous nor provocable secretion remained after diagnostic galactography, so that a segment resection was required. In all tissue specimens, the cause of the pathologic secretion was found histologically; most often, it was fibrocystic disease or solitary intraductal papilloma (21.5% each). In 32.3% of the specimens, findings with a prospective significance (papillomatosis, carcinoma in situ or invasive carcinoma) were discovered and further operative treatment was initiated. The colour of the discharge allowed no prediction of the histological findings. In 28.6% (8/28) of the carcinomas, secretion was bilateral. In 46.4% of the specimens containing carcinoma, papillomatosis was also detected; vice versa, papillomatosis was associated with carcinoma in 22.8%. The recurrence rate of 1.6% indicates the efficiency of this method in removing the pathology. The diagnostic value of galactography for the prediction of findings with a prospective significance was considerably reduced by a rate of 37.5% false-negatives; therefore, we have decided to omit diagnostic galactography in our patients. Now, provided extra-mammary causes of the nipple discharge have been excluded and mammography has been inconspicuous, a selective excision of the ductal-lobular unit is performed after preoperative chromogalactography. 相似文献
7.
Pernes JM; Vitoux JF; Brenoit P; Raynaud A; Parola JL; Roth JP; Angel CY; Fiessinger JN; Roncato M; Gaux JC 《Radiology》1986,158(2):481-485
Thirty-five patients hospitalized for recent angiographically documented arterial occlusion in the legs (27 femoropopliteal arteries and eight grafts) benefited from local fibrinolytic therapy delivered at the site of the occlusion with a 4- or 5-F catheter. This therapy combined a continuous urokinase (UK) infusion of 1,000 U/kg/hour and a lysyl plasminogen (LYS-PLG) infusion of 15 microkatals every 30 minutes. Angiographically confirmed lysis was obtained in 85% of the cases. Only 3% of the patients had major and 6% had minor groin hematomas. Only two patients had concentrations of fibrinogen as low as 100 mg/dl. Intravascular infusion of UK-LYS-PLG is as effective as streptokinase. Its excellent tolerance makes it a good alternative in the treatment of acute ischemia in the lower limbs. 相似文献
8.
Between the years 1968-1988 30 patients with primary carcinoma of the fallopian tube were treated in the Department of Obstetrics and Gynecology of the University of Kiel. In 27 cases the initial treatment consisted of total abdominal hysterectomy and bilateral salpingo-oophorectomy. In 3 cases where the patients had undergone surgical treatment in another hospital a second operation for completion was performed. 2 patients received no further treatment after surgery. Postoperative radiotherapy was given to 20 patients and a combined treatment with radiation and polychemotherapy was implemented in 5 cases. Postoperative treatment in 3 patients was poly-chemotherapy alone. The 5-year-survival rate taking all tumor stages and modes of therapy employed into consideration was 36.7%. In analysing the survival rate for small numbers as directly related to postoperative treatment a 5-year-survival rate for radiotherapy of 35% (7/20) and for radiation therapy plus poly-chemotherapy of 40% (2/5) was found. After operative treatment followed by poly-chemotherapy alone one of three patients survived after 5 years. 相似文献
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Intestinal obstruction proximal to a transition zone without an interposed physical barrier usually indicates Hirschsprung disease. The authors report one case of focal small bowel muscular thinning just distal to a transition zone that produced clinical and radiographic findings that simulated long-segment Hirschsprung disease in a 2-day-old infant. 相似文献