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951.
Is saliva serology useful for the diagnosis of Helicobacter pylori?   总被引:4,自引:0,他引:4       下载免费PDF全文
BACKGROUND: The Cortecs Diagnostics Helisal Assay test is a quantitative immunoassay for salivary IgG antibodies against Helicobacter pylori. Saliva can be obtained simply with the kit in the general practitioners surgery. AIMS: To compare the new saliva serological test for H pylori with 'gold standard' evidence of H pylori infection (antral biopsy specimens for histology, culture, and urease test) and a new serum serological test. PATIENTS: Eighty six unselected dyspeptic patients undergoing endoscopy. METHODS: Each patient provided saliva and serum before endoscopy for H pylori serology, which was compared against 'gold standard' evidence of infection. RESULTS: Thirty two patients were H pylori positive by the 'gold standard' tests. At a cut off value of 0.15 EU/ml the saliva test had a sensitivity of 88% and a specificity of 71%, with a negative predictive value of 90%. If patients who were taking omeprazole or had recent antibiotics are excluded, the sensitivity is unchanged but the specificity increases to 79%. The serum test had a similar sensitivity of 85% but better specificity of 78%. CONCLUSION: Serum testing remains the best serological test for H pylori in the hospital setting. Saliva testing may have a role in epidemiological studies and in screening dyspeptic patients in general practice, especially in children in whom venesection is more difficult.  相似文献   
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Telaprevir and Boceprevir are the first direct acting antivirals approved for chronic hepatitis C in combination with peg-interferon alfa and ribavirin.Pancytopenia due to myelotoxicity caused by these drugs may occur,but severe hematological abnormalities or aplastic anemia(AA) have not been described.We collected all cases of severe pancytopenia observed during triple therapy with telaprevir in four Spanish centers since approval of the drug in 2011.Among 142 cirrhotic patients receiving treatment,7 cases of severe pancytopenia(5%) were identified and three were consistent with the diagnosis of AA.Mean age was 59 years,five patients had compensated cirrhosis and two patients had severe hepatitis C recurrence after liver transplantation.Severe pancytopenia was diagnosed a median of 10 wk after the initiation of therapy.Three patients had pre-treatment hematological abnormalities related to splenomegaly.In six patients,antiviral treatment was interrupted at the onset of hematological abnormalities.Two patients died due to septic complications and one patient due to acute alveolar hemorrhage.The remaining patients recovered.Severe pancytopenia and especially AA,are not rare during triple therapy with telaprevir in patients with advanced liver disease.Close monitoring is imperative in this setting to promptly detect serious hematological disorders and to prevent further complications.  相似文献   
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In instrumental conditioning, newly acquired actions are generally goal‐directed and are mediated by the relationship between the action and its consequences or outcome. With continued training, however, the performance of such actions can become automatic, reflexive or habitual and under the control of antecedent stimuli rather than their consequences. Recent evidence suggests that habit learning is mediated by plasticity in the dorsolateral striatum (DLS). To date, however, no direct evidence of learning‐related plasticity associated with overtraining has been reported in this region, nor is it known whether, or which, specific cell types are involved in this learning process. The striatum is primarily composed of two classes of spiny projection neurons, the striatonigral and striatopallidal spiny projection neurons, which express dopamine D1 and D2 receptors, and control direct and indirect pathways, respectively. Here we found evidence of a post‐synaptic depression in DLS striatopallidal projecting neurons in the indirect pathway during habit learning in mice. Moreover, this training‐induced depression occluded post‐synaptic depression induced by co‐activation of D2 receptors and transient receptor potential vanilloid 1 (TRPV1) channels, implying that this pathway is involved in habit learning. This hypothesis was further tested by disrupting this signal pathway by knocking out TRPV1 channels, resulting in compromised habit learning. Our findings suggest that post‐synaptic plasticity at D2 neurons in the DLS mediates habit learning and, by implicating an interaction between the D2 receptor and TRPV1 channel activity, provide a potential drug target for influencing habitual action control.  相似文献   
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Background: Peri‐implantitis is a complex polymicrobial biofilm‐induced inflammatory osteolytic gingival infection that results in orofacial implant failures. To the best knowledge of the authors, there are no preclinical in vivo studies in implant dentistry that have investigated the inflammatory response to known microbial biofilms observed in humans. The aim of this study is to develop a novel peri‐implant rat model using an established model of polymicrobial periodontitis. Methods: Wistar rats were used for the study of experimental peri‐implantitis. One month after extraction of maxillary first molars, a titanium mini‐implant was inserted. Two months after implant healing, implants were uncovered, and abutment fixing was done using cyanoacrylate to prevent abutment loosening. Rats were separated into two groups (group A: polymicrobial‐infected and group B: sham‐infected). One week after healing of abutments, rats were infected with Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia for 12 weeks. Bacterial colonization, bone resorption, and implant inflammation were evaluated by polymerase chain reaction (PCR), microcomputed tomography, and histology, respectively. Results: Three rats with four implants in the infection group and two rats with three implants in the sham‐infection group were analyzed. PCR analysis revealed presence of bacterial genomic DNA, and infection elicited significant immunoglobulin (Ig)G and IgM antibody responses, indicating bacterial colonization/infection around implants. Infection induced an enhanced mean distance from implant platform to the first bone‐to‐implant contact, extensive peri‐implantitis with advanced bone resorption, and extensive inflammation with granulation tissue and polymorphonuclear leukocytes. Conclusions: To the best knowledge of the authors, this is the first study to develop a novel rat model of polymicrobial peri‐implantitis. With modifications to improve implant retention it could offer significant advantages for studies of initiation and progression of peri‐implantitis.  相似文献   
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Introduction and ObjectivesSarcopenia is one of the most common complications of cirrhosis, associated with an increased risk of morbidity and mortality. It is therefore necessary to perform a proper nutritional evaluation in these patients. Although CT scans are the gold standard for diagnosing sarcopenia, they are not widely used in clinical practice. There is thus a need to find indirect methods for identifying sarcopenia in patients with cirrhosis.Material and methodsThis is a cross-sectional study consecutively including all cirrhotic outpatients who underwent CT scans.ResultsA total of 174 patients met all the inclusion criteria and none of exclusion criteria. Fifty-five patients (31.6%) showed sarcopenia on CT scans. Multivariate analysis revealed that the factors that were independently associated with the presence of sarcopenia on CT scans were: male sex (OR 11.27, 95% CI 3.53–35.95; p<0.001), lower body mass index (BMI) (OR 1.22, 95% CI 1.11–1.34; p<0.001) and lower phase angle by bioelectrical impedance analysis (OR 2.83, 95% CI 1.74–4.6; p<0.001). With the variables identified from the multivariate study we developed a nomogram that allows ruling out the presence of sarcopenia. Our model rules out sarcopenia with an area under the receiver operating characteristic curve value of 0.8. The cutoff point of the probability to rule out sarcopenia was 0.6 (sensitivity 85%, specificity 73%, Youden index 0.58, PPV 82.5% and NPV 91.3%).ConclusionSince CT scans involve exposure to radiation and their availability is limited, we propose using this nomogram as an indirect method to rule out sarcopenia in cirrhotic patients.  相似文献   
958.
Metabolic Brain Disease - The aim of the present study was to evaluate the anti-glioma activity of 3-(4-fluorobenzyl)-5-(4-methoxybenzylidene)thiazolidine-2,4-dione (AV23) in a preclinical model of...  相似文献   
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