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21.
In this study, we examined the effect of theory of planned behavior (TPB) constructs on the intention to quit water pipe smoking by using an observational, survey-based, cross-sectional study design with a convenient sample of Arab American adults in Houston, Texas. Multivariate logistic regression models were used to determine predictors of intention to quit water pipe smoking in the next year. A total of 340 participants completed the survey. Behavioral evaluation, normative beliefs, and motivation to comply were significant predictors of an intention to quit water pipe smoking adjusting for age, gender, income, marital status, and education. Interventions and strategies that include these constructs will assist water pipe smokers in quitting.  相似文献   
22.
Despite the availability of the female condoms and theoretically based interventions to promote its use, studies have indicated a low level of acceptability of their use among women in most populations. We aimed to determine female condom use prevalence and the potential markers among African-American women. In an intervention trial to test the efficacy of the Information-Motivation-Behavioral Skills model in increasing condom use, we utilized the baseline data of 280 subjects and examined the potential predictors of female condom use. Chi square statistic and unconditional logistic regression were used to test for group independence among users and non-users of the female condom and to assess the potential markers of female condom use respectively. After adjustment for relevant covariates associated independently with female condom use, the significant potential markers for female condom use were age, multiple sexual relationships, knowledge of female condom, and educational status. Women having multiple sexual relationships compared with a monogamous relationship were five times more likely to use the female condom, while women with high school education were three times more likely to use the female condom; prevalence odds ratio, POR=5.32, 95% CI=1.79-15.83 and POR=3.01, 95% CI=1.01-8.93. Women who were not knowledgeable of the female condom, compared to those who were, were 81% less likely to use the female condom, POR=0.19, 95% CI=0.08-0.45. Among African-American women in this sample, knowledge of female condom use, age, educational status, and multiple sexual relationships were significant markers of female condom use. This study is therefore suggestive of the need to educate African-American women on female condom use, given the obstacles in male condom negotiation, especially among the socio-economically challenged.  相似文献   
23.
Background: IL-4 is a cytokine that induces differentiation of naive helper T cells into Th2 cells. Once activated by IL-4, Th2 cells subsequently produce additional IL-4. Objective: To examine the effect of IL-4 on IL-17 production and its effect in Collagen-Induced Arthritis (CIA) mice. Method: In this study, a chicken collagen-II-induced experimental arthritis (CIA) model was used in DBA/1 mice to investigate the relationship between IL-4 and IL-17 as well as other inflammatory factors. On the 38th day after the mice were induced with CIA, the expression of IL-17 and IL-4 as well as IFN-γ and IL-13 in sera of the mice was measured by QRT-PCR and ELISA. Result: The result of QRT-PCR analysis of IL-17 and IL-4 mRNA levels in the spleen showed that IL-17 is increased significantly at the onset of CIA in the spleen (p<0.01). Meanwhile, IL-17 is generally reduced at the peak of CIA but IL-4 is increased significantly at this peak in the spleen when the weight of the animal was taken into consideration (p<0.05). Conclusion: IL-4 can be involved in the production of IL-17 at especially the peak of CIA. These results imply that the inhibition of IL-17 may decrease the expression of IL-1β and IL-6 production which will result in the aggravation of arthritis.  相似文献   
24.
Uniformed services personnel are at an increased risk of HIV infection. We examined the HIV/AIDS knowledge and sexual risk behaviors among female military personnel to determine the correlates of HIV risk behaviors in this population. The study used a cross-sectional design to examine HIV/AIDS knowledge and sexual risk behaviors in a sample of 346 females drawn from two military cantonments in Southwestern Nigeria. Data was collected between 2006 and 2008. Using bivariate analysis and multivariate logistic regression, HIV/AIDS knowledge and sexual behaviors were described in relation to socio-demographic characteristics of the participants. Multivariate logistic regression analysis revealed that level of education and knowing someone infected with HIV/AIDS were significant (P < 0.05) predictors of HIV knowledge in this sample. HIV prevention self-efficacy was significantly (P < 0.05) predicted by annual income and race/ethnicity. Condom use attitudes were also significantly (P < 0.05) associated with number of children, annual income, and number of sexual partners. Data indicates the importance of incorporating these predictor variables into intervention designs.  相似文献   
25.
ObjectiveTo investigate the antimalarial activity of ethanol extract of Aspilia africana (A. africana) leaf.MethodsThe ethanol extract of A. africana leaf (100–400 mg/kg) was screened for blood schizonticidal effect against chloroquine-sensitive Plasmodium berghei (P. berghei) in mice both in early and established models of antimalarial studies.ResultsThe leaf extract exhibited significant (P<0.05) antiplasmodial activity in 4-day early infection and in established infection tests with a considerable mean survival time comparable to that of standard drug, chloroquine (10 mg/kg).ConclusionsThe findings show that ethanol extract of A. africana leaf possesses potent antiplasmodial activity which justify the use in ethnomedicine and can be developed in malaria therapy.  相似文献   
26.
In 1986, the Centers for Disease Control (CDC) implemented the Model Performance Evaluation Program (MPEP) to evaluate the performance of laboratories that test for antibody directed against human immunodeficiency virus type 1 (HIV-1). The impetus for developing this program came from the recognition of a need to assess the quality of existing and changing laboratory technology and to ensure that the quality of testing was sufficient to meet medical and public health needs. To develop the program, CDC chose HIV-1 antibody testing as the first specific application for assessing the quality of laboratory performance because (a) of the importance of accurate and reproducible test results for acquired immunodeficiency syndrome (AIDS) surveillance, prevention, and treatment programs; (b) HIV-1 testing technology is new to many laboratories; and (c) HIV-1 testing practices and applications continue to evolve. Unlike proficiency testing programs, the MPEP is not limited to assessing quality in the analytical step, alone. It will also assess quality in the preanalytical and postanalytical steps of the testing process, that is, from the time a test is requested until the clinician who ordered the test takes an action based on the test result. The participating laboratories furnish the information needed for the performance evaluation program by (a) completing questionnaires designed to describe HIV-1 testing laboratories and their testing practices, (b) analyzing specially prepared sample panels for HIV-1 antibody reactivity, and (c) reporting results to CDC.  相似文献   
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28.
Ferriprotoporphyrin IX (FP) dissolved in 0.025N NaoH in concentrations of 0.01 - 0.04 microM/ul platelet suspension competitively inhibited platelet aggregation induced by a low concentration of collagen. 14C-serotonin release was also inhibited. Higher concentrations of collagen overcame the aggregation inhibition. A similar pattern of results was obtained with thrombin-, and arachidonic acid-induced aggregation and release. With ristocetin, there was little inhibition of aggregation although serotonin release was inhibited. ADP-induced aggregation was partially inhibited except at FP concentrations of 0.91 microM/mul. FP caused only platelet shape change and serotonin release of up to 8.1%. These changes were not associated with significant platelet lysis and could also not be attributed to pH or temperature changes. There was no inhibition of collagen-induced aggregation in PRP, but FP precipitates aggregated washed platelets and caused serotonin release. These results show that FP in solution inhibited platelet aggregation induced by the different agents studied. It did not interfere with platelet agglutination induced by ristocetin. The mechanism(s) of aggregation inhibition remains to be clarified.  相似文献   
29.
The normal range of factor VIII coagulant activity (derived from log potency ratio) in some sections of the Nigerian population has been established at 0.65--5.55 iu/ml with a geometric mean of 1.90 iu/ml. This was determined against an acceptable standard (MRC Human 68/413 with activity o.66 iu/ml). The distribution of the potency ratio was log normal. The level was not affected by age or an abnormal haemoglobin (Hb A + S or A + C). The mean activity in females was significantly higher than the mean value in male subjects. With the use of a stable standard, our results show that the conclusions of some previous studies in respect of some of the parameters such as population distribution but which did not use a recognized standard, were valid. Within the age limits of our subjects, age did not affect the population level of factor VIII coagulant activity.  相似文献   
30.
Chloroquine, its N-dealkylated metabolites, and chloroquine N-oxides were detected in the urine of pregnant women who were receiving chloroquine medication whereas chloroquine and its nonpolar metabolites, desethyl- and didesethylchloroquine and 7-chloro-4-aminoquinoline, have been found in the neonates' urine, blood, and cord blood. We used thin-layer chromatography to separate chloroquine and its metabolites after their extraction from biological fluids. These compounds were identified by comparing their chromatographic and ultraviolet spectrophotometric characteristics with those of reference compounds. That chloroquine and its relatively nonpolar metabolites (including one without the alkyl side-chain, 7-chloro-4-aminoquinoline) cross the placenta is demonstrated by the presence of these compounds in the cord blood, neonatal systemic blood, and neonatal urine. The selective transfer of the compounds in the cord blood, neonatal system blood, and neonatal urine. The selective transfer of the compounds across the placenta and the clinical implications of these findings are discussed.  相似文献   
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