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Rationale
The effectiveness of cannabidiolic acid (CBDA) was compared with other potential treatments for anticipatory nausea (AN), using a rat model of contextually elicited conditioned gaping reactions.Objective
The potential of ondansetron (OND), Δ9-tetrahydrocannabinol (THC), chlordiazepoxide (CDP), CBDA, and co-administration of CBDA and tetrahydrocannabinolic acid (THCA) to reduce AN and modify locomotor activity was evaluated.Materials and methods
Following four pairings of a novel context with lithium chloride (LiCl), the rats were given a test for AN. On the test trial, they received pretreatment injections of the following: vehicle, OND (0.1 or 1.0 mg/kg), THC (0.5 mg/kg), CBDA (0.0001, 0.001, 0.01, 0.1 mg/kg or 1.0 mg/kg), CDP (1, 5, or 10 mg/kg) or co-administration of subthreshold doses of CBDA (0.1 μg/kg), and THCA (5 μg/kg). Immediately following the AN test trial in all experiments, rats were given a 15 min locomotor activity test. Finally, the potential of CBDA (0.001, 0.01, 0.1, and 1 mg/kg) to attenuate conditioned freezing to a shock-paired tone was assessed.Results
THC, CBDA, and CDP, but not OND, reduced contextually elicited gaping reactions. Co-administration of subthreshold doses of CBDA and THCA also suppressed AN, and this effect was blocked by pretreatment with either a cannabinoid receptor 1 (CB1) receptor antagonist or a 5-hydroxytryptamine 1A (5-HT1A) receptor antagonist. CDP (but not CBDA, THC or CBDA and THCA) also suppressed locomotor activity at effective doses. CBDA did not modify the expression of conditioned fear.Conclusions
CBDA has therapeutic potential as a highly potent and selective treatment for AN without psychoactive or locomotor effects. 相似文献Aims—To investigate the significance ofendotoxaemia in biliary obstruction using the EndoCab assay and assessthe specificity of the humoral response to endotoxin compared with anexogenous antigenic challenge (tetanus toxoid, TT).
Methods—Three groups of adult male Wistar ratswere studied: no operation, sham operation, and bile duct ligation for21 days (BDL). In the second study, rats rats received priorimmunisation with TT.
Results—In the preliminary experiment, plasmaACGA was significantly increased in the BDL group (306.6 (18.3)%versus 119.9(6.7)% and 105.2 (4.6)% in the sham and no operationgroups, respectively; p<0.001). Although the mean endotoxinconcentration in the BDL group was greater than that in the controlgroups this was not significant. There was a strong positivecorrelation between ACGA and endotoxin concentrations (p=0.0021). Inthe second study mean ACGA after 21 days of BDL was significantlyelevated (267.1 (31.2)% versus 101.6 (21.2)% at baseline, p<0.0001).ACGA was unaffected in the other two groups. TT antibody concentrationsfell in all three groups; only in the BDL group was the fallsignificant (97.6(5.3)% versus 78.8 (4.2)% at baseline, p<0.05).
Conclusions—The specific rise in ACGA supportsthe hypothesis that endotoxin has an integral role in thepathophysiology of obstructive jaundice. The production of anticoreglycolipid antibodies specifically reflects systemic endotoxaemia inthis model. The EndoCab assay provides a novel, sensitive, and specificmethod for endotoxin detection.
相似文献
Purpose
To assess the feasibility of collecting patient-reported outcomes data with wireless touch screen tablet computers in the adult oncology palliative care setting.Methods
Patients were provided with tablet computers during scheduled clinic visits and answered online queries about their experience over the past week in the health domains of anxiety, depression, fatigue, pain interference, physical function, instrumental social support, sleep impairment, diarrhea, constipation, nausea, vomiting, anorexia, dyspnea, neuropathy, and spiritual values.Results
Content analysis of patient interviews indicates that wireless touch screen tablet computers are a feasible approach for collecting patient-reported outcome measures by palliative care cancer patients presenting in clinic. Most patients indicated that the questionnaire was easy to answer. However, all but one patient requested some form of assistance, and many reported difficulties attributable to a lack of familiarity with the device, interpretation of certain questions, and wireless connectivity-related issues.Conclusions
This feasibility study demonstrates that tablet computers have the potential to efficiently and reliably collect patient-reported health status measures among palliative care cancer patients presenting in clinics. The use of these devices may lead to substantial improvements by making patient-reported outcomes available for clinical decision-making. 相似文献Bats are carriers of potentially zoonotic viruses, therefore it is crucial to identify viruses currently found in bats to better understand how they are maintained in bat populations and evaluate risks for transmission to other species. Adenoviruses have been previously detected in bats throughout the world, but sampling is still limited. In this study, 30 pooled-guano samples were collected from a cave roost of Myotis velifer in Oklahoma. A portion of the DNA polymerase gene from Adenoviridae was amplified successfully in 18 M. velifer samples; however, DNA sequence was obtained from only 6 of these M. velifer samples. One was collected in October 2016, one in March 2017, and 4 in July 2017. The October and March samples contained viral DNA that was 3.1% different from each other but 33% different than the novel viral sequence found in the July 2017 samples. Phylogenetic analysis of these fragments confirmed our isolates were from the genus Mastadenovirus and had genetic diversity ranging from 20 to 50% when compared to other bat adenoviruses.
相似文献