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排序方式: 共有9491条查询结果,搜索用时 15 毫秒
61.
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
62.
S Berezin M S Medow J Bernarducci L J Newman 《JPEN. Journal of parenteral and enteral nutrition》1988,12(4):392-393
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
63.
A H Newman J Covington M Oleshansky B W Jackson B A Weissman H Leader P K Chiang 《Biochemical pharmacology》1990,40(6):1357-1364
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
64.
Skeletal effects of calcitonin in ovariectomized rats 总被引:3,自引:0,他引:3
T J Wronski C F Yen K W Burton R C Mehta P S Newman E E Soltis P P DeLuca 《Endocrinology》1991,129(4):2246-2250
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
65.
Arthrograms of the temporomandibular joint were obtained in 20 symptomatic joints that had previous reconstructive arthroplasty with disk repositioning because of internal derangements. Preoperative arthrograms were available for comparison in 18 joints. Symptoms resulting in a postoperative arthrogram included pain, limited ability to open the mouth, and clicking of the joints. Postoperative arthrographic findings included limited anterior translation of the condyle (90%), irregularity in outline of the intraarticular contrast agent (60%), a conical configuration of the posterior recess (25%), decreased size of the joint (28%), anterior displacement of the meniscus (25%), and perforated meniscus (15%). Many of these findings may have resulted from fibrosis and scarring, which may be a response to intraarticular bleeding. The mechanism by which the fibrosis causes the postsurgical arthrographic features is discussed. 相似文献
66.
67.
68.
R B Rothman V Bykov A Reid B R De Costa A H Newman A E Jacobson K C Rice 《Neuropeptides》1988,12(3):181-187
Norbinaltorphimine (nor-BNI) is a bifunctional reagent developed as a selective antagonist of the kappa opioid receptor. In this paper we examined the in vitro selectivity of nor-BNI, 6-desoxy-6 beta-fluoronaltrexone (cycloFOXY), and the enantiomer of cycloFOXY, among opioid receptor subtypes. Nor BNI exhibited the highest affinity for kappa binding sites labeled by 3H-U69593 (Ki = 1.8nM), and was 27- to 29-fold less potent at mu and delta binding sites. In contrast, cycloFOXY had the highest affinity for mu binding sites (Ki = 2.62 nM), and bound to kappa and delta binding sites with Ki's of 9.3 nM and 89 nM, respectively. The enantiomer of cycloFOXY, did not inhibit binding even at concentrations greater than 10 microM, validating in part the use of 18F-labeled (+)-cycloFOXY to estimate "non-specific binding" in positron emission tomography. Additionally, we report that (S,S)-U50 488 and (R.R)-U50 488 bind to kappa binding sites labeled by 3H-U69 593 with Ki's of 0.89 nM and 299 nM, respectively. 相似文献
69.
"What is growth anyway? Can one talk about positive growth in childhood, neutral growth in maturity, and negative growth in old age?" Our goal is to help promote normal positive growth in infants and children. To achieve this, we must be cognizant of the morphologic changes of both normal and abnormal bone formation as they are reflected in the radiographic image of the skeleton. The knowledge of the various causes and the pathophysiologic mechanisms of the disturbances of bone growth and development allows us to recognize the early radiographic manifestations. Endocrine and metabolic disorders affect the whole skeleton, but the early changes are best seen in the distal ends of the femurs, where growth rate is most rapid. In skeletal infections and in some vascular injuries two-or three-phase bone scintigraphy supercedes radiography early in the course of the disease. MRI has proved to be very helpful in the early detection of avascular bone necrosis, osteomyelitis, and tumor. Some benign bone tumors and many bone dysplasias have distinct and diagnostic radiographic findings that may preclude further studies. In constitutional diseases of bone, including chromosomal aberrations, skeletal surveys of the patient and all family members together with biochemical and cytogenetic studies are essential for both diagnosis and genetic counseling. Our role is to perform the least invasive and most informative diagnostic imaging modalities that corroborate the biochemical and histologic findings to establish the definitive diagnosis. Unrecognized, misdiagnosed, or improperly treated disturbance of bone growth can result in permanent deformity usually associated with disability. 相似文献
70.
Use of the "blast path" may be helpful in patients where positioning for ESWL treatments is difficult. Good pressures are maintained along the blast path and an alternate fracture mechanism may be in effect. The rate of fragmentation, assessed using model material, decreases with distance beyond F2. 相似文献