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There has been an upsurge of academic interest in using focus groups (FGs) as a main or stand-alone qualitative method. In this article, the authors introduce a recently developed ancillary method to FGs called interviewing the moderator. The method is employed immediately after an FG and consists of a one-on-one interview with the FG moderator by another member of the research team. The authors argue, with reference to a specific study, that interviewing the moderator adds a new and valuable dimension to group interviews used in research. They describe how this method came about and provide a concrete example of its use in a recently completed research project. They discuss several advantages of the interview, among them that it provides information about group interaction and participant behavior, and furnishes additional data on what is discussed when the tape recorder is turned off.  相似文献   
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**This is a prospective Norwegian study of a group of adolescents with an experience of parental divorce or separation (n=413) and a comparison group without this experience (n=1758). Mean age at T1 was 14.4 years and mean age at T2 was 18.4 years. Parental divorce was prospectively associated with a relative change in anxiety and depression, subjective well-being, self-esteem, and school problems. Considering boys separately, parental divorce was prospectively associated only with school problems. Among the girls, divorce was prospectively associated with all variables. The effect of divorce on relative change was partially mediated by paternal absence.  相似文献   
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OBJECTIVE: To evaluate the role of target temperature (28 degrees or 34 degrees C) in cardiac surgery on regional oxygenation during hypothermia and rewarming and systemic inflammatory response. DESIGN: Prospective, controlled, and randomized clinical study. SETTING: University hospital. PARTICIPANTS: Elderly patients (mean age 70 +/- 2 years) with acquired heart disease with an anticipated bypass time exceeding 120 minutes (n = 30). INTERVENTIONS: The patients were cooled to either 28 degrees C (n = 15) or 34 degrees C (n = 15). At hypothermia, bypass blood flow was reduced twice from full flow (2.4 L/min/m(2) body surface area [BSA]) to 2.0 L/min/m(2). MEASUREMENTS AND MAIN RESULTS: Hepatic and jugular venous oxygen tension and saturation were higher at 28 degrees C than at 34 degrees C. In comparison with the preoperative values, at 28 degrees C hepatic venous values were higher; whereas at 34 degrees C, they were lower. The reduction of pump blood flow during hypothermia, from 2.4 to 2.0 L/min/m(2)was accompanied by reductions of central, jugular, and hepatic oxygenation at both target temperatures. During rewarming, central and regional venous oxygenation decreased irrespective of the preceding temperature. The decrease was most pronounced in hepatic venous blood, with the lowest individual values <10%. Serum concentrations of C3a and IL-6 increased during hypothermia and increased further during rewarming irrespective of the preceding temperature. CONCLUSION: During cardiopulmonary bypass, hypothermia at 28 degrees C increases regional and central venous oxygenation better than at 34 degrees C. In contrast, venous oxygenation decreases during rewarming irrespective of the preceding temperature. No significant difference in the systemic inflammatory response associated with target temperature was detected.  相似文献   
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Infant feeding recommendations for HIV-positive mothers differ from recommendations to mothers of unknown HIV-status. The aim of this study was to compare feeding practices, including breastfeeding, between infants and young children of HIV-positive mothers and infants of mothers in the general population of Uganda.  相似文献   
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63 evaluable patients with myelodysplastic syndromes (MDS) and 15 with acute myelogenous leukemia (AML) were randomized between low-dose ara-C (arm A) and low dose ara-C in combination with 13-cis-retinoic acid (13-CRA) and 1 alpha-hydroxy-vitamin D3 (1 alpha D3) (arm B). 69 patients were evaluable and 18 (26.1%) responded to therapy. The addition of 13-CRA and 1 alpha D3 had no positive influence on survival of the patients, remission rates or duration of remissions. 12/27 patients in arm A and 6/29 patients in arm B progressed from MDS to AML during the course of the study (p = 0.0527). Arm B gave significantly more side-effects than arm A (p = 0.005). Therapeutic effects of 13-CRA and 1 alpha D3 on MDS is not supported by this study. However, an inhibiting effect on AML development in some MDS subgroups cannot be excluded.  相似文献   
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Physicochemical properties of lipid nanoparticles (LN), such as size, size distribution and surface charge, have a major influence both, on in vitro stability and delivery of the incorporated drug in vivo. With the purpose of understanding how these properties are influenced by variations of LN composition (e.g. lipid and surfactant type and concentration) 2(2) factorial designs with centre point were applied for several types of lipids and surfactants in the present study. Tested factors and levels were the type and concentration of lipid (cetyl palmitate, Dynasan 114 and Witepsol E85) at the concentrations of 5%, 10% and 15%, in combination with type and concentration of surfactant (polysorbate 20, 40, 60 and 80 and poloxamer 188 and 407) at concentrations of 0.8%, 1.2% and 2.0%. Responses measured within the design space were the mean size and polydispersity index (photon correlation spectroscopy), content of microparticles (optical single particle sizing), macroscopic appearance, pH and zeta potential on the day of production, 1 and 2 years after production. Multivariate evaluation and modelling were performed starting with a principal component analysis (PCA) and followed by partial least square regression analysis (PLS) to assess both qualitative and quantitative influence of the investigated factors in the LN. Our study showed that both, lipid and surfactant concentration and the type of surfactant are crucial parameters for the particle size of the LN prepared by high pressure homogenisation (HPH). For LN stability during 2 years both, lipid and surfactant types and concentrations were identified as the most relevant parameters. Among the surfactants most suitable for producing LN with small sizes were the polysorbates and the lipid yielding best storage stability was cetyl palmitate. Furthermore, the models allowed the prediction of the mean size of LN that could be achieved with a certain lipid/surfactant combination and concentration. The obtained results are considered useful for future design of stable LN formulations without the need of extensive empirical testing of formulation parameters within the given HPH technology.  相似文献   
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OBJECTIVE: To examine physician-assessed medical signs and patient-reported medical symptoms as correlates of 3 quality of life (QOL) outcomes in patients with systemic sclerosis (SSc): disability, pain, and psychosocial adjustment. METHODS: One hundred fourteen patients with SSc underwent a comprehensive clinical examination including determination of skin thickening [Modified Rodnan Skin Score (MRSS)]. Patients reported current symptoms and completed standardized questionnaires assessing disability and pain (Health Assessment Questionnaire) and psychosocial adjustment (Psychosocial Adjustment to Illness Scale). Regression analysis was used to examine physician-determined and patient-reported correlates of the 3 outcomes. RESULTS: MRSS was a significant correlate of all outcomes, although it explained only a small amount of the variance in psychosocial adjustment. Patient-reported postprandial bloating was the strongest correlate of psychosocial adjustment, explaining more than twice as much variance as MRSS. After accounting for MRSS, patient-reported dependent edema significantly correlated with all outcomes. For disability, significant correlates were physician-determined joint tenderness and number of tender points, and patient-reported joint pain on motion, joint contracture, extremity ulcers other than digital, and dyspnea. Patient-reported joint tenderness was significantly associated with pain. Regression analysis supported a model in which disability and pain mediated the relationship between MRSS and psychosocial adjustment. CONCLUSION: Skin score is strongly associated with disability and pain, but only weakly associated with psychosocial adjustment. Dependent edema has negative implications across quality-of-life outcomes. Disability and pain mediate the relationship between disease severity and psychosocial adjustment to disease. Assessment (including self-report of patient symptoms) of specific medical signs and symptoms may indicate SSc patients experiencing diminished QOL.  相似文献   
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