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41.
The ureteral access set was used 43 times during an 18-month period between 1984 and 1985. Stones lodged throughout the ureter and in the renal pelvis were extracted with a success rate of 51 per cent. Of the upper tract strictures 92 per cent were dilated successfully. Filling defects were diagnosed in 88 per cent of the cases. Foreign bodies were retrieved, Double-J stents were placed and biopsies were successful in each case. Ureteral perforation in 28 per cent of the cases was caused by the dilator in 8 of 12 (19 per cent over-all). The technique and short-term results are discussed. Long-term followup data are not yet available.  相似文献   
42.
Resection of a Wilms' tumor that extends into the vena cava or right atrium results in excellent survival when combined with adjuvant therapy. Preoperative identification of the presence of intravascular tumor thrombus and the level of vascular involvement is essential. It facilitates safe surgical resection, with cardiopulmonary bypass immediately available for retrohepatic and atrial tumors. Six patients with intracaval or intracardiac tumor thrombus were treated over a 5-year period with no perioperative deaths. Preoperative chemotherapy was useful in two patients with extensive tumors and pulmonary metastases. Our results using an integrated management plan suggest that an aggressive surgical approach is justified for this extensive variant of Wilms' tumor.  相似文献   
43.
Recognition of thalidomide defects.   总被引:4,自引:0,他引:4       下载免费PDF全文
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44.
A 12-year-old girl is described who developed rectal bleeding 5 months after being diagnosed as having a Coombs-positive hemolytic anemia. Colonoscopy showed that the rectal bleeding was due to ulcerative proctitis. This is the first case report of Coombs-positive hemolytic anemia preceding the onset of ulcerative proctitis in a child.  相似文献   
45.
46.
Weight at baseline and posttreatment was measured for 1096 participants in a smoking relapse prevention trial: 42.1% maintained their weight, 42.5% gained more than 1 kg and 15.4% lost more than 1 kg during the eight-week treatment program. Abstainers (n = 383) gained more than four times the weight gained by relapsers (n = 713) (Abstainers: 1.6 kg, Relapsers: 0.4 kg, p less than .0001). In order to examine the anorexic properties of nicotine gum. Abstainers were classified into nicotine gum user and non-user categories. Users gained significantly less weight than non-users although the difference was small (Users: 1.1 kg, Non-users: 1.8 kg, p less than .004). A dose-response relationship was observed between number of cigarettes smoked per day at baseline and weight gain. Higher cigarette consumption was associated with increased weight gain in both gum user (p less than .004), and non-user groups (p less than .02). There was no significant difference in weight gain between Abstainers who later relapsed at 6 months and those who maintained abstinence (p less than .29). Although the impact of nicotine gum on weight gain was small, this apparent property of the substance may be useful in encouraging cessation among smokers who perceive weight gain as a potential stumbling block to success.  相似文献   
47.
Nocturnal nasogastric feeding (NGF) supplementation is an effective means of supplying calories to children with chronic diseases which may impair caloric and nutritional intake. Herein, we describe our experience with 18 patients who were taught NGF. They were divided into two groups: one group was instructed in the hospital which is the typical situation, whereas the second group was instructed at home. No complications were associated with NGF taught either at home or in the hospital. Our experience, therefore, indicates that nocturnal NGF can be successfully taught at home.  相似文献   
48.
The development of selective irreversible ligands has proven to be an invaluable technique for the isolation, purification and characterization of many receptor proteins. An isothiocyanato-derivative of the muscarinic antagonist aprophen was synthesized and evaluated as a potential irreversible ligand for muscarinic receptors. This compound (aprophit) displaced [3H]N-methylscopolamine binding from rat cerebral cortex with a Ki of 3.1 x 10(-7) M. The inhibition was concentration-dependent and could not be reversed by extensive washing. Aprophit inhibited the acetylcholine-stimulated release of catecholamines from isolated, perfused guinea pig adrenal glands in a concentration-dependent manner. This inhibition was not reversed by perfusing the tissue with Locke's solution and was not due to a non-selective acylation by the isothiocyanate function. The data suggest that aprophit is selectively acylating muscarinic receptor proteins and thus may be useful in their further characterization.  相似文献   
49.
Skeletal effects of calcitonin in ovariectomized rats   总被引:3,自引:0,他引:3  
Although calcitonin (CT) has been shown to be effective for the prevention of bone loss in early postmenopausal women, the skeletal effects of the hormone specifically during the early stages of estrogen deficiency have not been characterized histomorphometrically to date. The current study involves use of the ovariectomized (OVX) rat as an animal model for early postmenopausal bone loss to perform such a histomorphometric analysis. One group of OVX rats was injected sc with salmon CT on alternate days for a 6-week period. Additional groups of OVX and sham-operated control rats were treated with vehicle alone. In comparison to control rats, the proximal tibia of vehicle-treated OVX rats were characterized by a 3-fold decrease in cancellous bone volume and significant increases in osteoblast surface (+200%), osteoclast surface (+143%), mineralizing surface (+111%), mineral apposition rate (+36%), bone formation rate (+181%), and longitudinal bone growth (+38%). In contrast, treatment of OVX rats with CT normalized tibial cancellous bone volume and significantly decreased all of the above cellular- and fluorochrome-based indices of bone turnover to near control levels. The results indicate that CT treatment depresses bone turnover and prevents the development of osteopenia in OVX rats. These findings are consistent with the bone protective effect of CT in early postmenopausal women and further support the OVX rat as an animal model for the preclinical evaluation of prophylactic treatments for postmenopausal bone loss.  相似文献   
50.
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