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41.
BACKGROUND: Leaving the hospital against medical advice has been associated with increased morbidity and readmission. Factors associated with the risk of leaving against medical advice among HIV/AIDS patients or injection drug users have not been examined in detail. OBJECTIVES: To examine the clinical and social factors associated with leaving against medical advice (AMA) from a specialized HIV/AIDS ward among patients who reported a history of injection drug use. METHODS: All patients with a history of injection drug use admitted to the HIV/AIDS ward at St. Paul's Hospital, Vancouver, British Columbia (the largest specialized HIV/AIDS hospital ward in Canada) between April 1997 and October 2000 were reviewed retrospectively. A multivariate logistic regression model utilizing a generalized estimating equation algorithm identified factors associated with leaving the hospital AMA. RESULTS: Of the 1056 hospital admissions to the HIV/AIDS ward by patients with a history of injection drug use, 263 (24.9%) resulted in leaving the hospital AMA. Independent positive predictors of leaving AMA included recent injection drug use (adjusted odds ratio [AOR] = 2.08, 95% confidence interval [CI]: 1.41-3.07) and aboriginal ethnicity (AOR = 1.55, 95% CI: 1.05-2.28). Discharge AMA was also more likely to occur on weekends (AOR = 2.27, 95% CI: 1.49-3.48) and on days when social assistance payments were issued (AOR = 2.95, 95% CI: 1.70-5.10). Factors that independently reduced the odds of hospital discharge AMA included in-hospital methadone use (AOR = 0.49, 95% CI: 0.32-0.76), social support (AOR = 0.33, 95% CI: 0.21-0.51), and older age (per 10-year increment, AOR = 0.56, 95% CI: 0.43-0.73). CONCLUSIONS: Among HIV-positive patients with a history of injection drug use, the odds of leaving the hospital AMA were reduced for subjects who received inpatient methadone treatment, were of older age, or had social supports. Addiction treatment and interventions that enhance social supports in marginalized populations at risk for hospital discharge AMA should be further explored.  相似文献   
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Methane Dry Reforming is one of the means of producing syngas. CeNi0.9Zr0.1O3 catalyst and its modification with yttrium were investigated for CO2 reforming of methane. The experiment was performed at 800 °C to examine the effect of yttrium loading on catalyst activity, stability, and H2/CO ratio. The catalyst activity increased with an increase in yttrium loading with CeNi0.9Zr0.01Y0.09O3 catalyst demonstrating the best activity with CH4 conversion >85% and CO2 conversion >90% while the stability increased with increases in zirconium loading. The specific surface area of samples ranged from 1–9 m2/g with a pore size of 12–29 nm. The samples all showed type IV isotherms. The XRD peaks confirmed the formation of a monoclinic phase of zirconium and the well-crystallized structure of the perovskite catalyst. The Temperature Program Reduction analysis (TPR) showed a peak at low-temperature region for the yttrium doped catalyst while the un-modified perovskite catalyst (CeNi0.9Zr0.1O3) showed a slight shift to a moderate temperature region in the TPR profile. The Thermogravimetric analysis (TGA) curve showed a weight loss step in the range of 500–700 °C, with CeNi0.9Zr0.1O3 having the least carbon with a weight loss of 20%.  相似文献   
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Patent holding pharmaceutical firms are modeled as price-discriminating international monopolies. In an unregulated world market, firms set monopoly prices in each national market. Three types of regulatory rules: (i) 'reasonable' relationship rule, (ii) international price comparison rule, and, (iii) therapeutic class comparison rule, are examined. While price regulation may lead to lower introductory prices for new drugs, the price of existing drugs may increase. Domestic price regulation may increase foreign prices. Canadian data supported the model's predictions. Policy makers should anticipate these responses that affects the entire vector of drug prices and not just those subject to specific regulations.  相似文献   
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Objective To compare the efficacy and safety of intravaginal misoprostol versus dinoprostone cervical gel for cervical ripening and labour induction. Methods We carried out an experimental clinical trial in which we enrolled 130 cervical consecutive patients with cervical ripening, randomly assigned to one of the following two treatment groups: (1) intravaginal misoprostol and (2) intracervical dinoprostone gel. A total of 50 μm of misoprostol was placed in the posterior vaginal fornix every 6 h for a maximum period of 24 h and 0.5 mg of dinoprostone was administrated in the uterine cervix every 6 h, for a maximum period of 24 h. The primary outcome measure was the number (rate) of women who went to vaginally deliver within 24 h of the protocol initiation. Results Among 130 patients evaluated, 65 were allocated to the misoprostol group and 65 to the dinoprostone group. The proportion of vaginal delivery within 24 h was significantly higher in the misoprostol group (75%) than in the dinoprostone group (53.8%) (RR = 1.40, 95% CI [1.07–1.45], P = 0.02). There was no significant difference between the mean time interval of delivery in the misoprostol group and the dinoprostone group (14.9 vs.15.8 h) (P = 0.51). The Bishop score was significantly higher in the misoprostol group, 6 h after the onset of the study (1.38; relative risk, 95% CI [1.02–1.85], P = 0.03). The Caesarean delivery rate for fetal distress was higher in the dinoprostone group (21 vs. 10.8%, P = 0.15). The tachysystole (Misoprostol 6.1% vs. dinoprostone 4.6%, relative risk 1.15, 95% CI [0.6–2.24]) and hyperstimulation syndrome rates (Misoprostol 7.6% vs. dinoprostone 4.6%, relative risk 1.26, 95% CI [0.72–2.24]) were slightly increased in the misoprostol group than in the dinoprostone group without reaching the level of statistical signification. Conclusion Misoprostol as used in this protocol is more effective than cervical dinoprostone gel application in the cervical ripening and labour induction. There is a tendency for an increase in the rate of tachysystole and hyperstimulation syndrome.  相似文献   
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Although numerous paediatric-based health-related quality-of-life (HR-QOL) instruments are currently in use, there still remain conceptual, methodological and developmental issues to address. This paper provides an up-to-date critical review of the HR-QOL literature in paediatric medicine.Our analysis indicates that there is no consensus on how HR-QOL and overall QOL should be defined and measured in children. It is recommended that future studies focus on operationalising and distinguishing these constructs from each other and from traditional health-status measures. A clear empirical basis for generating instrument items and for prioritising specific domains must be described. Researchers should consider using the data gathered during their first interviews as a springboard from which to test their ideas of HR-QOL and QOL, reformulate concepts and subsequently retest their notions before developing instruments.Related to methodological challenges, consistency and agreement are still used interchangeably when comparing child and parent reports of children's HR-QOL. The Pearson correlation is a measure of co-variation in scores, and not a measure of agreement. We recommend that researchers focus on determining agreement as opposed to consistency. Few, if any, attempts have been made to account for the possibility that a response shift may have occurred in the evaluation of HR-QOL. Most studies have compared HR-QOL scores of children with illness with their healthy peers. As such, there is a dearth of knowledge regarding the normative process of adaptation within the context of illness. It is recommended that researchers focus on gathering data using a relative standard of comparison. We further recommend that researchers interpret HR-QOL data in line with their intended purpose. Regarding developmental consideration, particular attention ought to be paid to developing instruments that consider children's emerging sense of self, cognitive capacity and emotional awareness. Instruments that include items that are age appropriate are more likely to maximise reliability and validity of reports.The results of many HR-QOL instruments are applied in pharmacotherapeutic and pharmacoeconomic assessments. However, there has been relative infrequent application of economically valid HR-QOL tools (utility scales) and the use of HR-QOL scales as outcome measures in paediatric drug trials. As such, few cost-utility analyses have been performed to inform paediatric decision making. In addition, many of the concerns in the development of HR-QOL instruments should also be applied to the utility scales such that they reflect adequately children's preferences for health states.  相似文献   
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We reviewed the clinical measures used in rheumatoid arthritis (RA) economic evaluations with respect to their relevance and sensitivity to changes in survival, health-related quality of life (HR-QOL) and costs. We compared the measures from the economic perspective and discussed the validity of methods used to extrapolate beyond the trial data. Cost-effectiveness evaluations of disease-modifying antirheumatic drugs in RA were identified by searching MEDLINE, EMBASE, Econlit and NHS EED databases. Studies were retained if they extrapolated beyond randomized controlled trial evidence using relationships between clinical measures, costs and utilities.In the 22 studies identified, clinical severity was measured using the Health Assessment Questionnaire (HAQ) Disability Index, the American College of Rheumatology (ACR) response criteria, the Disease Activity Score (DAS) or a combination of the HAQ and DAS. The HAQ is correlated with mortality, costs and HR-QOL instruments, and several studies used linear relationships to model these associations. However, a polynomial relationship or discrete states may be more appropriate for patients at the extremes of the disease spectrum, and numerous HAQ health states may be required to capture differences in mortality risk. While the ACR response criteria is a more comprehensive measure than the HAQ, it is a relative measure, which creates difficulties when estimating absolute changes in HR-QOL, costs and mortality risk. The evidence base linking DAS scores with HR-QOL instruments, costs and mortality is less robust, possibly due to the comparatively recent development of the measure and the limited number of possible scores (mild/moderate/severe). While there is some evidence of a relationship between DAS scores and costs, the DAS does not capture all aspects of HR-QOL, and no significant relationship has been established with mortality risk.Evidence suggests the HAQ to be the primary clinical measure for use in economic evaluations as it is measured in almost all clinical studies, and is closely correlated to health utilities, mortality and costs. While new developments suggest the sensitivity of health states may be improved by combining the HAQ with measures such as the DAS, further research is required in this area. Further research is also required to explore the advantages in using either continuous or discrete health states.  相似文献   
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A new steroid leucisterol (1) and a new peroxy acid urticic acid (2) along with methoxybenzyl benzoate (3), 4-hydroxy benzoic acid (4), beta-sitosterol (5), and ursolic acid (6), have been isolated from the chloroform soluble fraction of the whole plant of Leucas urticifolia. Their structures were elucidated on the basis of nuclear magnetic resonance (1D and 2D NMR) spectral data. Leucisterol showed potent inhibitory activity against butyrylcholinesterase enzyme.  相似文献   
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