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61.
62.

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   
63.
Conclusive evidence of endotoxaemia in biliary obstruction   总被引:10,自引:1,他引:10       下载免费PDF全文
W Clements  P Erwin  M McCaigue  I Halliday  G Barclay    B Rowlands 《Gut》1998,42(2):293-299
Background—Endotoxaemia is implicated in thepathophysiology of obstructive jaundice. The EndoCab enzyme linkedimmunosorbent assay (ELISA) is a novel assay which measures endogenousantibody (IgG) to the inner core region of circulating endotoxins (ACGA).
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   
64.
65.
66.
We found that 14.3% (15/105) of Amblyomma maculatum and 3.3% (10/299) of Dermacentor variabilis ticks collected at 3 high-use military training sites in west-central Kentucky and northern Tennessee, USA, were infected with Rickettsia parkeri and Rickettsia montanensis, respectively. These findings warrant regional increased public health awareness for rickettsial pathogens and disease.  相似文献   
67.
The response rate of non‐M3 acute myeloid leukemia (AML) to all trans retinoic acid has been limited. Using Affymetrix expression arrays, we found that in diverse AML blasts RXRA was expressed at higher levels than RARA and that mouse Ctsg‐PML‐RARA leukemia responded to bexarotene, a ligand for RXRA. We therefore performed a phase I study of combination bexarotene and decitabine in elderly and relapsed AML patients. We found that this combination was well tolerated, although outcomes were modest (1 CRi, and 3 PR among 19 patients). Correlative studies found that patients with clinical response had increased differentiation to bexarotene both in vivo and ex vivo, suggesting that pre‐treatment analysis might identify a more susceptible subgroup of patients. Am. J. Hematol. 89:E103–E108, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   
68.

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   
69.
Cancer driver mutations (CDMs) are necessary and causal for carcinogenesis and have advantages as reporters of carcinogenic risk. However, little progress has been made toward developing measurements of CDMs as biomarkers for use in cancer risk assessment. Impediments for using a CDM-based metric to inform cancer risk include the complexity and stochastic nature of carcinogenesis, technical difficulty in quantifying low-frequency CDMs, and lack of established relationships between cancer driver mutant fractions and tumor incidence. Through literature review and database analyses, this review identifies the most promising targets to investigate as biomarkers of cancer risk. Mutational hotspots were discerned within the 20 most mutated genes across the 10 deadliest cancers. Forty genes were identified that encompass 108 mutational hotspot codons overrepresented in the COSMIC database; 424 different mutations within these hotspot codons account for approximately 63,000 tumors and their prevalence across tumor types is described. The review summarizes literature on the prevalence of CDMs in normal tissues and suggests such mutations are direct and indirect substrates for chemical carcinogenesis, which occurs in a spatially stochastic manner. Evidence that hotspot CDMs (hCDMs) frequently occur as tumor subpopulations is presented, indicating COSMIC data may underestimate mutation prevalence. Analyses of online databases show that genes containing hCDMs are enriched in functions related to intercellular communication. In its totality, the review provides a roadmap for the development of tissue-specific, CDM-based biomarkers of carcinogenic potential, comprised of batteries of hCDMs and can be measured by error-correct next-generation sequencing. Environ. Mol. Mutagen. 61:152–175, 2020. Published 2019. This article is a U.S. Government work and is in the public domain in the USA. Environmental and Molecular Mutagenesis published by Wiley Periodicals, Inc. on behalf of Environmental Mutagen Society.  相似文献   
70.
Lee  Dana N.  Angiel  Meagan 《Virus genes》2020,56(1):99-103

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   
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