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991.
992.
Fourteen participating centers registered 33 patients on a Southwest Oncology Group Study of adults with acute non-lymphocytic leukemia (ANLL). Induction consisted of cytosine arabinoside 70 mg/m2 days 1-7 by continuous intravenous (i.v.) infusion, VP-16 50 mg/m2 i.v. over 1 hour days 1-3, and daunomycin 30 mg/m2 i.v. bolus days 1-3. Twenty-five patients (median age 69 years) were evaluable for response. Eleven (44%) achieved a remission marrow but only 8 fulfilled both blood and marrow criteria for complete remission. Of the 11 patients with a remission marrow, there were no patients over 70 years of age. Major coexisting disease data were evaluated. Only 5 patients had no major coexisting disease and 4 of those 5 achieved a remission marrow. The study illustrates and underscores the following problems of remission induction in the elderly: (a) increased susceptibility to the stress of the induction period, with 6 patients (24%) dying before treatment day sixteen; (b) disease resistance to antileukemic therapy with persistent ANLL in 6 patients (24%), despite two induction courses; and (c) hematopoietic stem cell sensitivity in the elderly with marrow regeneration failure documented in 2 patients (8%) following induction. Acute nonlymphocytic leukemia in the elderly has a poor prognosis, and novel therapeutic approaches are warranted.  相似文献   
993.
An increase in sympathetic nervous system (SNS) activity in the obese has been described by some but not all investigators. It is possible that an increase in SNS tone may play a role in the predisposition to atherosclerotic cardiovascular disease noted in the obese. The effect of dietary weight loss or exercise training on resting SNS activity in moderately obese subjects has not been extensively studied and the results of previous studies are conflicting. Therefore, we prospectively evaluated resting SNS activity in healthy moderately obese subjects randomized to either a three month dietary weight loss (n = 13) or endurance exercise training (n = 18). All subjects were weight stabilized on a constant composition diet for 10 days prior to study both before and after the interventions. Although both groups lost weight, weight loss was greater in the diet group (-13.6 +/- 6.7 vs -2.3 +/- 3.4 kg, P less than 0.001). The composition of weight loss was also different with 32 percent of total weight loss as fat free mass (FFM) in the dieters compared to no significant change in FFM in the exercisers. The caloric requirement for weight stabilization declined after the diet but increased following exercise training (-247 vs + 202 kcal/day, P less than 0.001). No significant changes in blood pressure occurred in either group, and neither group had a significant change in resting plasma norepinephrine concentration. Plasma epinephrine concentrations were also unchanged. However, SNS activity as reflected by arterialized plasma NE kinetics revealed that NE appearance rate declined by 17 percent after dietary weight loss (P less than 0.01), but was not significantly changed after exercise training. These results suggest that dietary weight loss is more effective than exercise training in reducing overall resting SNS activity in normotensive subjects. Since exercise training is known to reduce the SNS response to a given submaximal workload, a combination of diet plus exercise might be the most effective way to reduce overall SNS activity and its possible role in the premature atherosclerosis associated with obesity.  相似文献   
994.
This is a report by an ad hoc committee to the Joint Council of the Society for Vascular Surgery and the International Society for Cardiovascular Surgery (North American Chapter) concerning guidelines that hospitals may use or modify when judging individual applicants for hospital and operating room privileges in vascular surgery. The committee recognizes that the completion of training and obtaining a board certificate is testimony to the qualification but not necessarily the competence of an individual to practice vascular surgery. This report identifies three categories of applicant for privileges in vascular surgery; the surgeon who just completed training, the surgeon who completed training after 1984, and the surgeon who completed training before 1984. In addition, the committee recognizes the importance of periodic vascular surgery privileges renewal for established surgeons. Several pathways are defined for use by hospital privilege committees to evaluate the competence of an individual to be granted privileges in general vascular surgery. The ad hoc committee also has outlined a program for evaluation of established surgeons for renewing privileges in vascular surgery using a mechanism of case outcome audit. Finally, a review mechanism, potential corrective actions, and an appeals mechanism are also suggested. This report represents optimal criteria that may require modification by individual hospitals to meet local community needs and standards. It is the hope of the ad hoc committee that this report will help hospitals and practicing physicians improve the quality of care and treatment outcome in patients with vascular disease.  相似文献   
995.
Some patients with severely ischemic lower limbs continued to have severe ischemic changes in the foot after revascularization procedures and appropriate four leg compartment fasciotomies. Rather than abandon efforts at limb salvage, we performed adjunctive fasciotomies of the ankle and foot in 11 of these patients. These included five cases of acute traumatic superficial femoral or popliteal artery occlusions (three penetrating injuries; two blunt injuries) requiring primary repair or interposition vein graft; three cases of penetrating injury to all infrapopliteal arteries requiring tibiotibial vein bypasses; two cases of iatrogenic thrombosis of the common femoral artery requiring thrombectomy and patch angioplasty; and one case of a traumatically amputated leg requiring replantation. All bypasses remained patent after the distal fasciotomies. Limb salvage and good functional results were achieved in 10 of the 11 patients from 4 to 28 months postoperatively. One patient required a below-knee amputation because of bleeding from an infected graft. Thus fasciotomy of the ankle and foot should be considered during acute revascularizations when a distal bypass occludes without obvious reasons, or when the foot remains ischemic or shows signs of compartment syndrome unrelieved by standard leg fasciotomy.  相似文献   
996.
997.
998.
Limb-salvage was the indication for 90% of 206 attempted PTAs in 175 patients between 1976 and 1982. Life-table patency rates at 4 years for the angiographically successful iliac PTA and femoropopliteal PTA were 78% and 50%, respectively. PTA of eight iliac, seven femoropopliteal, nine tibial, and two subclavian arteries and one autogenous saphenous vein graft (ASV) were unsuccessful. Of these, 17 subsequently underwent successful bypass grafts and five required below-knee amputations. Ten iliac, 37 femoropopliteal, four tibial, and two ASV graft PTAs failed. Of 20 repeat attempts at PTA, only two have achieved long-term patency. Appropriate surgery allowed limb salvage in 23 of 36 early failures (less than 3 months) and 12 of 14 late failures (greater than 3 months), and usually consisted of the same operation that would have been performed had PTA not been attempted. Fifty-two complications were classified according to the method of treatment. Fourteen warranted surgery, but in 10 this was successfully achieved by the same operation that would have been required had PTA not been performed.  相似文献   
999.
Blask  AR; Sanders  RC; Gearhart  JP 《Radiology》1991,179(1):79-83
The sonograms of five neonates with an obstructed urogenital sinus and four with an obstructed cloaca were retrospectively reviewed to determine the sonographic features and the role of pre- and postnatal sonography in the diagnosis and management of hydrocolpos. On pre- and/or postnatal sonograms, the obstructed genital tract was visualized in seven neonates as a large cystic pelvic-abdominal mass, which was the markedly distended urine-filled vagina. One neonate had multiple cystic masses, which resulted from an obstructed duplex genital tract. In one of the neonates with an obstructed cloaca, the anomaly was not diagnosed. The bladder was compressed by the distended vagina and was not visualized in five patients. A vaginal fluid-debris level in six patients was a key finding that distinguished the vagina from the bladder. Obstruction of the urinary tract was an associated feature. An obstructed uterovaginal anomaly with renal dysplasia and oligohydramnios on prenatal sonograms indicates a poor prognosis. Sonography contributes to the diagnosis of an obstructed genital tract and helps define the internal genital anatomy.  相似文献   
1000.
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