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711.
Shortly after leptin was first discovered, it was hailed as the key to understanding obesity. However, it didn’t take long for investigators to realize that the hormone was more than a feedback signal to inhibit further food intake. Since those early days, leptin has been well characterized in rodents. It exerts an influence in many physiologic processes, including food intake, thermoregulation, fertility, thyroid function, adrenal function, sympathetic nerve activation, renal function, blood vessel tone, and blood pressure. No longer a satiety hormone, it is being looked at from many different perspectives. One such perspective is its influence on the cardiovascular system. This review highlights some of the work in this area.  相似文献   
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713.

Background

Falls are the leading cause of fatal and nonfatal unintentional injury among older adults in the United States. Multifaceted falls prevention programs, which have been reported to reduce the risk for falls among older adults, usually include a medication review and modification component. Based on a literature search, no randomized trials that have examined the effectiveness of this component have been published.

Objective

The aim of this article was to report on a retrospective process evaluation of data from a randomized, controlled trial conducted to examine the effectiveness of a medication review intervention, delivered through community pharmacies, on the rate of falls among community-dwelling older adults.

Methods

Patients were recruited through 32 pharmacies in North Carolina. Participants were community-dwelling older adults at high risk for falls based on age (≥65 years), number of concurrent medications (≥4), and medication classes (emphasis on CNS-active agents). The process evaluation measured the recruitment of patients into the study, the process through which the intervention was delivered, the extent to which patients implemented the recommendations for intervention, and the acceptance of pharmacists' recommendations by prescribing physicians.

Results

Of the 7793 patients contacted for study participation, 981 (12.6%) responded to the initial inquiry. A total of 801 (81.7%) participated in an eligibility interview, of whom 342 (42.7%) were eligible. Baseline data collection was completed in 186 of eligible patients (54.4%), who were randomly assigned to the intervention group (n = 93) or the control group (n = 93). Pharmacists delivered a medication review to 73 of the patients (78.5%) in the intervention group, with 41 recommendations for changes in medication, of which 10 (24.4%) were implemented. Of the 31 prescribing physicians contacted with pharmacists' recommendations, 14 (45.2%) responded, and 10 (32.3%) authorized the changes.

Conclusions

Based on the findings from the present study, coordination of care between community pharmacists and prescribers needs to be improved for the realization of potential beneficial effects of medication management on falls prevention.  相似文献   
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715.
OBJECTIVE: This study examined whether informal caregiver psychologic distress decreases the likelihood of influenza vaccination for community-dwelling elderly with dementia. A secondary aim was to determine whether psychologic distress mediates the relationship between other predisposing, enabling, and medical need variables and vaccination. METHODS: Data were drawn from the 1998 National Longitudinal Caregiver Survey. The final sample consisted of 1406 community-dwelling male veterans with dementia and their coresiding female informal caregivers. Presence of caregiver psychologic distress was measured using the Boston Short Form of the Center for Epidemiologic Studies Depression Scale. Vaccination was identified by examining Veteran Administration Outpatient Data Files for visits indicating influenza vaccine administration during the 1998 influenza vaccine season (September 1 to December 31). Multivariate path analysis with observed variables was used to estimate direct and indirect probit path coefficients between independent variables, caregiver psychologic distress, and veteran vaccination. RESULTS: As hypothesized, caregiver distress was significantly associated with a decreased likelihood of care-recipient vaccination (unstandardized coefficient [b] = -0.023, P < 0.01). Adjusted for other variables, the predicted probability of vaccination was 37.7% for care-recipients with nondistressed caregivers compared with 29.4% for care-recipients with distressed caregivers. Furthermore, a number of factors significantly influenced vaccination via their influence on psychologic distress. CONCLUSION: We conclude that caregiver psychologic distress may interfere with access to influenza vaccination in persons with dementia. Access to vaccination may be improved directly by detecting and treating emotional health problems in caregivers and indirectly by addressing precursors to caregiver distress.  相似文献   
716.
p16基因在消化系肿瘤的研究进展   总被引:1,自引:7,他引:1  
p16基因又称多重肿瘤抑制基因1(MTS1)、细胞周期素依赖激酶4的抑制物(cyclindependentkinase4inhibitor,CDK4I)或CDKN2,是新近发现的一个重要抑癌基因,与许多肿瘤的发生、发展关系密切.与p53基因相比,它具有突变率高、分子量小,易于标定的特点,因而很快成为肿瘤分子生物学、分子遗传学等学科的研究热点.目前,人们已从基础及临床诊治等多个角度对p16基因进行了研究.本文旨在综述p16基因与消化系肿瘤发生、发展的关系及p16基因治疗情况.1 p16基因的作用及…  相似文献   
717.
Depletion of endoplasmic reticulum Ca2+ stores leads to the entry of extracellular Ca2+ into the cytoplasm, a process termed capacitative or store-operated Ca2+ entry. Partially purified extracts were prepared from the human Jurkat T lymphocyte cell line and yeast in which Ca2+ stores were depleted by chemical and genetic means, respectively. After microinjection into Xenopus laevis oocytes, the extracts elicited a wave of increased cytoplasmic free Ca2+ ([Ca2+]i) that spread from the point of injection across the oocyte. Extracts from cells with replete organellar Ca2+ stores were inactive. The increases depended on extracellular Ca2+, were unaffected by the inositol 1,4,5-trisphosphate (IP3) inhibitor heparin or an anti-IP3 receptor antibody and were unchanged when the endoplasmic reticulum was segregated to the hemisphere opposite the injection site by centrifugation. Confocal microscopy revealed that [Ca2+]i increases were most pronounced at the periphery of the oocyte. The patterns of [Ca2+]i increases were replicated by computer simulations based on a diffusible messenger of about 700 Da that directly activates Ca2+ influx. In addition, ICRAC, a Ca2+ release-activated Ca2+ current monitored in Jurkat cells by whole-cell patch clamp recordings, was more rapidly activated when active extracts were included in the patch pipette than by the inclusion of a Ca2+ chelator or IP3. These data support the existence in yeast and mammalian cells depleted of Ca2+ stores of a functionally conserved diffusible calcium influx factor that directly activates Ca2+ influx.  相似文献   
718.
Loken  MR; Civin  CI; Bigbee  WL; Langlois  RG; Jensen  RH 《Blood》1987,70(6):1959-1961
The expression of two epitopes on glycophorin A (GPA) during erythroid development was examined on normal human bone marrow using quantitative flow cytometry. The highly correlated binding of two monoclonal antibodies, one sensitive and the other insensitive to glycosylation, indicated that the two epitopes were coordinately expressed during erythroid development. Both antigens reached a maximum expression during the early normoblast stage and were maintained at a constant amount per cell throughout further maturation to erythrocytes. These data suggest that glycosylation of GPA, as detected by antibodies recognizing blood group (M) and (N) antigens, does not increase during erythroid maturation.  相似文献   
719.
Background: The effective treatment for hepatocellular carcinoma(HCC) depends on early diagnosis. Previously, the abnormal expression of Wnt3a as the key signaling molecule in the Wnt/β-catenin pathway was found in HCC cells and could be released into the circulation. In this study, we used rat model of hepatocarcinogenesis to dynamically investigate the alteration of oncogenic Wnt3a and to explore its early monitor value for HCC. Methods: Sprague-Dawley rats(SD) were fed with diet 2-fluorenylac...  相似文献   
720.
Coronary artery aneurysms are the most serious complication of Kawasaki disease, and periodic screening examinations are necessary. Two-dimensional (2D) echocardiography represents the standard screening method; however, visualization of the distal coronary arteries is often limited. This report describes the complementary role of ultrafast computed tomography (CT) with 2D echocardiography in the evaluation of coronary artery aneurysms resulting from Kawasaki disease (mucocutaneous lymph node syndrome). Six pediatric patients with coronary aneurysms were examined with 2D echocardiography and ultrafast CT. Ten of 11 lesions were detected with ultrafast CT. The one missed coronary artery aneurysm was one of two contiguous aneurysms. Because of intersection thickness these two discrete aneurysms were interpreted as a solitary aneurysm. Ultrafast CT allowed detection of one aneurysm not initially visualized with echocardiography. In conclusion, ultrafast CT was found to be an effective complementary procedure with 2D echocardiography for noninvasively evaluating coronary artery aneurysms occurring as sequelae of Kawasaki disease.  相似文献   
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