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41.
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A number of vitamin D3 metabolites inhibit benzodiazepine- and dimethyl sulfoxide-induced differentiation of Friend erythroleukemia cells. The inhibition is dose dependent and occurs at nM concentrations. The order of potency of these compounds is 1,25-dihydroxycholecalciferol greater than 1,25,26-trihydroxycholecalciferol greater than 1,24R,25-trihydroxycholecalciferol greater than 1 alpha-hydroxycholecalciferol greater than 24R,25-dihydroxycholecalciferol greater than 25S,26-dihydroxycholecalciferol. The inhibition is maximal when the vitamin D3 analogs are added together with the inducer, and becomes progressively decreased with delayed addition. These results suggest that the vitamin D3 metabolites may play a regulatory role in erythropoiesis.  相似文献   
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If proven effective, vaginal microbicides and diaphragms will likely be part of a larger HIV prevention model that includes condoms and other prevention strategies. It is, therefore, important to understand how introducing new prevention methods may affect overall patterns of sexual risk behavior. Data presented were collected as part of a safety and feasibility study of ACIDFORM gel with a diaphragm among 120 women in South Africa. Interviews were administered at enrollment and months 1, 3, 5, and 6 of the trial. Focus groups were conducted at trial exit. Frequency of sex increased significantly after enrollment. This increase appears to be owing to perceived protection from HIV and greater sexual pleasure afforded by the gel. Male condom use was high overall but increased significantly from enrollment. Data suggest this is because of increased partner involvement, increased negotiating power afforded by study participation, and provision of free condoms perceived to be of high quality.  相似文献   
45.
Obsessive-compulsive disorder is increasingly recognized in patients of different age groups. Serotonergic agents, such as clomipramine, have been recently found to be useful in the management of this condition. However, unexpected side effects, such as dysphoria, aggressiveness, and paranoid ideation, may occur with therapeutic doses of this compound, as evidenced in the cases of two male adolescents presented here. Possible pathogenetic factors, involving serotonin and serotonin-receptor abnormalities are discussed. Management of these side effects is based on adequate dose reduction and monitorization.  相似文献   
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The following article is an attempt to encapsulate an historical overview of spirituality in nursing. Despite a plethora of information relative to spirituality in nursing, the decision was to do an eclectic overview that was not reflective of any one spiritual/religious group. The authors at times found this goal difficult when writing about the Pre-Christian and Christian eras. Most of the major religions have their own perspective on the concept of spirituality, and historical personalities recorded maybe reflective of that particular religion. Another factor that impacted on the writing of this article was the concept that spirituality was not always linked specifically to religion. Spirituality was an experiential component of the wonders of nature and life, a domain that the authors took into account but did not expound upon. Finally the authors realized that spirituality has almost always been an aspect of African-American life and certainly of those in nursing. To this end the authors realize that there is a need for more research in this area.  相似文献   
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Young children's ability to participate in conversation has been of particular interest in the study of pragmatic aspects of language. In this study, topics of conversation were investigated by videotaping 10 dyads of 4-year-old children during play. Ten-minute samples were analyzed according to a number of topic-dependent measures. Results revealed that all dyads evidenced some lengthy topics (13-91 utterances). Longer topics were characterized by three text-level functions. Enacting Scenarios, Describing, and Problem Solving. Nevertheless, three fourths of all dialogues were considered relatively short. Generally, partners contributed equally to dialogue, but in some dyads, 1 child dominated initiation. Findings of the study suggest that 4-year-olds are capable of extended participation in dialogue, at least part of the time. Naturalistic play settings may elicit samples of conversation that are representative of preschoolers' ability.  相似文献   
50.
Cardiovascular intervention for high-risk families: the Heart Smart Program   总被引:2,自引:0,他引:2  
The Heart Smart Family Health Promotion Program is a multidisciplinary, school-based program for cardiovascular risk reduction among high-risk children and their families. As a program that includes young adults at high risk, it is adaptable to a clinical practice. Nineteen fourth and fifth graders were selected as probands for elevated risk factors after a general screening to identify families for an intervention program. Twenty-three parents participated in a 12-week program focused on eating, exercise, and smoking behavior changes enhanced by behavicral support strategies. Weekly sessions were held in the auditorium/cafeteria of the elementary school and consisted of orientation and presentations, cardiovascular (CV) screening with medical feedback, activities, self-monitoring, counseling, and contingency contracting. Information gathered before and after the program included medical history, CV health knowledge and relevant behavior, blood pressure, serum lipid and lipoprotein values, anthropometric measurements, and urine electrolyte excretion. Both children and parents showed positive changes in eating habits and physical activity and significant changes in knowledge and blood pressure levels, while the children halted their weight gain. We believe this multidisciplinary, behavior-oriented, school-based program can be an effective cardiovascular risk intervention adaptable for a clinical office practice.  相似文献   
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