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31.
32.
Acute occlusions of the left circumflex coronary artery were performed in open-chest dogs. A control group (n = 19) was compared with three groups (total n = 17) pretreated once daily with different doses of the cardioselective beta-blocking drug atenolol (ICI 66 082) given by mouth for 5 days. Only animals without coronary collateral vessels were examined, having a mortality rate of 100% in the control group. Arrhythmias and ventricular fibrillation during the first 30 min after coronary occlusion showed a biphasic distribution in time (phase 1a and 1b). A lower degree of beta-adrenoceptor blockade reduced the incidence of arrhythmias and ventricular fibrillation in phase 1a, but fibrillation occurred in all animals during phase 1b. A higher dose of the beta-blocking drug protected the animals from ventricular fibrillation, and arrhythmias in phase 1a were greatly reduced. At all times the ventricular fibrillation threshold in the group pretreated with atenolol was significantly higher than in the control group. In both groups a significant decrease in ventricular fibrillation threshold was found only during phase 1a. The greater sensitivity of phase 1a arrhythmias to beta-blockade and the lack of a decrease in ventricular fibrillation threshold during phase 1b might indicate differences in the genesis of arrhythmias and fibrillation in phases 1a and 1b.  相似文献   
33.
BACKGROUND: The diagnosis of chronic hepatitis C virus infection is based on nucleic acid testing (NAT) for HCV-RNA. We evaluated whether total HCV core antigen testing could be a substitute for NAT testing. PATIENTS AND METHODS: Samples from 192 untreated chronic HCV positive patients previously tested for HCV-RNA by four different commercially available assays (SuperQuant, Amplicor HCV Monitor v 1.0 and v 2.0, Quantiplex) were tested for total HCV core antigen using the Ortho trak-C assay (Ortho Clinical Diagnostics, Raritan, NJ, USA). Furthermore, 52 HCV-RNA positive paired serum and plasma samples were analysed. Finally, inter-assay coefficients of variation for core antigen were determined by repeated testing of 59 samples. RESULTS: 172/192 (89.6 %) samples from untreated HCV patients showed positive results with the trak-C assay. Importantly, all but two trak-C positive samples were NAT positive. Only four of the twenty trak-C negative samples tested positive by two NAT assays with viral loads below 30,000 copies/mL. Moreover, HCV core antigen levels correlated significantly with HCV-RNA levels (r > 0.72; p > 0.001), gave consistent results in paired serum and plasma samples (r = 0.991), and showed a very low inter-assay variability (r = 0.943) independent of genotype. CONCLUSION: Based on the performance characteristics, easiness of use, and potential lower cost of the core Ag assay, we propose an alternative testing algorithm for establishing the diagnosis of chronic HCV infection in which the trak-C assay could substitute for NAT as the first choice for detection of HCV viraemia in anti-HCV positive individuals. NAT would only be necessary in rare cases with low viral load.  相似文献   
34.
Two children are reported in whom intestinal pseudo-obstruction was the initial manifestation of systemic sclerosis. Gastrointestinal symptoms and skin changes resolved or improved in both children following treatment with prednisone and penicillamine (case 1) or methotrexate (case 2), although radiological changes of the gastrointestinal tract persisted at 3 and 2 yr of follow-up, respectively.   相似文献   
35.

Background:

Monoamine reuptake inhibitors exhibit unique clinical profiles that reflect distinct engagement of the central nervous system (CNS) transporters.

Methods:

We used a translational strategy, including rodent pharmacokinetic/pharmacodynamic modeling and positron emission tomography (PET) imaging in humans, to establish the transporter profile of TD-9855, a novel norepinephrine and serotonin reuptake inhibitor.

Results:

TD-9855 was a potent inhibitor of norepinephrine (NE) and serotonin 5-HT uptake in vitro with an inhibitory selectivity of 4- to 10-fold for NE at human and rat transporters. TD-9855 engaged norepinephrine transporters (NET) and serotonin transporters (SERT) in rat spinal cord, with a plasma EC50 of 11.7ng/mL and 50.8ng/mL, respectively, consistent with modest selectivity for NET in vivo.Accounting for species differences in protein binding, the projected human NET and SERT plasma EC50 values were 5.5ng/mL and 23.9ng/mL, respectively. A single-dose, open-label PET study (4–20mg TD-9855, oral) was conducted in eight healthy males using the radiotracers [11C]-3-amino-4- [2-[(di(methyl)amino)methyl]phenyl]sulfanylbenzonitrile for SERT and [11C]-(S,S)-methylreboxetine for NET. The long pharmacokinetic half-life (30–40h) of TD-9855 allowed for sequential assessment of SERT and NET occupancy in the same subject. The plasma EC50 for NET was estimated to be 1.21ng/mL, and at doses of greater than 4mg the projected steady-state NET occupancy is high (>75%). After a single oral dose of 20mg, SERT occupancy was 25 (±8)% at a plasma level of 6.35ng/mL.

Conclusions:

These data establish the CNS penetration and transporter profile of TD-9855 and inform the selection of potential doses for future clinical evaluation.  相似文献   
36.
Objectives: Systematic screening for chronic hepatitis B and C does not yet exist in Germany. Therefore, the implementation of a screening approach within a preventive medical examination performed by primary care physicians (‘Check-Up 35+’) was evaluated in a recent prospective multicenter study. The present analysis estimates the financial consequences for the statutory health insurance by budget impact analysis.

Materials and methods: A Markov cohort model was developed consisting of 21 health states. Four different screening scenarios derived from the previous multicenter study were compared to usual care, a strategy without screening for hepatitis. Actual cost data for Germany were calculated and systematic literature searches for all input parameters were performed.

Results: The base case results in incremental costs for the screening strategies compared to no hepatitis screening of 165–227 € per patient in a 20-year horizon. Two main parameters influence the financial consequences: (A) detection and treatment increase the costs in the beginning. (B) Screening avoids hepatitis induced end-stage liver disease. The initial higher costs exceed the later savings. Sensitivity analyses demonstrate a strong impact of medication costs for the treatment of additionally detected hepatitis infections on the outcome. This finding is robust to sensitivity analysis.

Conclusions: The screening strategy proposed here implies additional costs for the statutory health insurance, however, a decision regarding its usefulness must consider criteria other than cost. For example, the high burden of disease due to liver cirrhosis and liver carcinoma should be considered. Therefore, an additional cost-effectiveness-analysis should be conducted.  相似文献   

37.
European Journal of Clinical Microbiology & Infectious Diseases - Complicated urinary tract infection (cUTI) is a frequent cause of morbidity. In this multinational retrospective cohort study,...  相似文献   
38.
ObjectivesWhen managing partially defective restorations, dentists can choose between repair and replacement. We aimed to assess the long-term treatment costs of repairs and replacements.MethodsPartially defective anterior and posterior composite restorations in permanent teeth had been repaired or replaced in a German university hospital and were retrospectively followed until censoring or one of the following events: (1) Extraction, (2) Major complications including placement of indirect restorations, endodontic treatments and extractions, or (3) Any complications including major complications and further direct restorations. Costs were estimated from a German mixed public-private-payer perspective. Cost-effectiveness differences were described using median-based incremental-cost-effectiveness ratios (ICERMEDIAN). Statistical analysis was performed using generalized linear mixed modeling (GLM), Chi2-test, and Wilcoxon rank-sum test (p < 0.05).ResultsA total of 616 repairs in 468 patients (follow-up: 4.9 ± 4.1 years) and 264 replacements in 218 patients (follow-up: 4.8 ± 4.3) were included. While replacements were associated with higher initial treatment costs, median annualized treatment costs did not significantly differ between repair (47.58 Euro [IQR: 24.41–107.04]) and replacement (50.64 Euro [IQR: 26.30–118.78]; p > 0.05), but were higher for molars (75.53 Euro [IQR: 24.41–92.18]) than incisors (45.03 Euro [IQR: 28.19–168.50]; p = 0.011). The difference in the % of extractions, major and any complications were minimal between both groups. The mean ICERMEDIAN of replacement vs. repair was -146.8 Euro/% when extractions were considered as outcomes. Regarding major and any complications, mean ICERMEDIAN amounted to 67.6 Euro/% and 23.9 Euro/%, respectively.SignificanceRepairs and replacements of partially defective restorations showed similar long-term costs and cost-effectiveness.  相似文献   
39.
Ghrelin is a recently identified growth hormone (GH) secretogogue whose administration not only induces GH release but also stimulates food intake, increases adiposity, and reduces fat utilization in mice. The effect on food intake appears to be independent of GH release and instead due to direct activation of orexigenic neurons in the arcuate nucleus of the hypothalamus. The effects of ghrelin administration on food intake have led to the suggestion that inhibitors of endogenous ghrelin could be useful in curbing appetite and combating obesity. To further study the role of endogenous ghrelin in appetite and body weight regulation, we generated ghrelin-deficient (ghrl(-/-)) mice, in which the ghrelin gene was precisely replaced with a lacZ reporter gene. ghrl(-/-) mice were viable and exhibited normal growth rates as well as normal spontaneous food intake patterns, normal basal levels of hypothalamic orexigenic and anorexigenic neuropeptides, and no impairment of reflexive hyperphagia after fasting. These results indicate that endogenous ghrelin is not an essential regulator of food intake and has, at most, a redundant role in the regulation of appetite. However, analyses of ghrl(-/-) mice demonstrate that endogenous ghrelin plays a prominent role in determining the type of metabolic substrate (i.e., fat vs. carbohydrate) that is used for maintenance of energy balance, particularly under conditions of high fat intake.  相似文献   
40.
Static and dynamic hyperinflation is an important factor of exertional dyspnea in patients with severe COPD. This proof-of-concept intervention trial sought to study whether laughter can reduce hyperinflation through repetitive expiratory efforts in patients with severe COPD. For small groups of patients with severe COPD (n = 19) and healthy controls (n = 10) Pello the clown performed a humor intervention triggering regular laughter. Plethysmography was done before and up to 24 hours after intervention. Laughing and smiling were quantified with video-analysis. Real-time breathing pattern was assessed with the LifeShirt™, and the psychological impact of the intervention was monitored with self-administered questionnaires. The intervention led to a reduction of TLC in COPD (p = 0.04), but not in controls (p = 0.9). TLC reduction was due to a decline of the residual volume. Four (22 [CI 95% 7 to 46] %) patients were ≥10% responders. The frequency of smiling and TLC at baseline were independent predictors of TLC response. The humor intervention improved cheerfulness, but not seriousness nor bad mood. In conclusion, smiling induced by a humor intervention was able to reduce hyperinflation in patients with severe COPD. A smiling-derived breathing technique might complement pursed-lips breathing in patients with symptomatic obstruction.  相似文献   
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