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61.
62.

Objective

To analyze disease‐free survival in patients with antineutrophil cytoplasmic antibody (ANCA)–associated small‐vessel vasculitis (AAV) treated with cyclophosphamide only or switched to azathioprine after 3 months of full remission while taking cyclophosphamide.

Methods

We analyzed disease‐free survival in all consecutive patients diagnosed with AAV between 1990 and 2000 at our center. Patients were treated with cyclophosphamide only (1990–1996) or switched to azathioprine after 3 months of remission while taking cyclophosphamide (1997–2000). All patients received at least 12 months of followup.

Results

Of the total 128 patients, 53 (41%) relapsed. Forty‐four of the 128 patients (34%) had been switched to azathioprine therapy. Disease‐free survival at 2 and 4 years was 76% and 65% in the cyclophosphamide group compared with 76% and 51% in the azathioprine group. In patients with proteinase 3 (PR3) classic ANCA (C‐ANCA)–associated vasculitis who were switched to azathioprine (n = 33), a positive C‐ANCA titer at the moment of treatment switch (n = 13) was significantly associated with relapse (RR 2.6, 95% confidence interval 1.1–8.0; P = 0.04). In patients with a negative ANCA titer at the time of switch to azathioprine, disease‐free survival at 2 and 4 years was 80% and 62%, which was identical to that for patients treated with cyclophosphamide only. In patients who were ANCA‐positive at the time of treatment switch, disease‐free survival at 2 and 4 years was only 58% and 17%.

Conclusion

Switching cyclophosphamide to azathioprine after induction of remission in patients with PR3‐ANCA‐associated vasculitis who are still ANCA‐positive at the time of treatment switch is associated with a high risk of relapse.
  相似文献   
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Vascular abnormalities and glycogen accumulation in vascular smooth muscle fibres have been described in Pompe disease. Using carotid-femoral pulse wave velocity (cfPWV), the gold standard methodology for determining aortic stiffness, we studied whether aortic stiffness is increased in patients with Pompe disease. Eighty-four adult Pompe patients and 179 age- and gender-matched volunteers participated in this cross-sectional case-controlled study. Intima media thickness and the distensibility of the right common carotid artery were measured using a Duplex scanner. Aortic augmentation index, central pulse pressure, aortic reflexion time and cfPWV were assessed using the SphygmoCor® system. CfPWV was higher in patients than in volunteers (8.8 versus 7.4 m/s, p?<?0.001). This difference was still present after adjustment for age, gender, mean arterial blood pressure (MAP), heart rate and diabetes mellitus (p?=?0.001), and was shown by subgroup analysis to apply to the 40-59 years age group (p?=?0.004) and 60+ years age group (p?=?0.01), but not to younger age groups (p?=?0.99). Except for a shorter aortic reflexion time (p?=?0.02), indirect indicators of arterial stiffness did not differ between patients and volunteers. Relative to volunteers (20 %), more Pompe patients had a history of hypertension (36 %, p?=?0.005), and the MAP was higher than in volunteers (100 versus 92 mmHg, p?<?0.001). This study shows that patients with non-classic Pompe disease have increased aortic stiffness and blood pressure. Whether this is due to glycogen accumulation requires further investigation. To reduce the potential risk of cardiovascular diseases, we recommend that blood pressure and other common cardiovascular risk factors are monitored regularly.  相似文献   
65.
Journal of Thrombosis and Thrombolysis - Direct oral anti-coagulants (DOACs) reduce hospital length-of-stay (LOS) in patients with acute pulmonary embolism (PE) in clinical trials. There is a...  相似文献   
66.
Annals of Hematology - The prognostic significance of hypercalcemia in lymphoma has only been studied on small series to date. We conducted a retrospective, monocentric, matched-control study that...  相似文献   
67.
Abstract

Hermansky-Pudlak syndrome (HPS) is a rare autosomal recessive disorder characterized by defective biogenesis of lysosome-related organelles. Clinical manifestations include a bleeding diathesis due to a platelet delta storage pool deficiency, oculocutaneous albinism, inflammatory bowel disease, neutropenia, and pulmonary fibrosis. Ten genes associated with HPS are identified to date, and each gene encodes a protein subunit of either Biogenesis of Lysosome-related Organelles Complex (BLOC)-1, BLOC-2, BLOC-3, or the Adaptor Protein-3 complex. Several genetic variants and phenotypic heterogeneities are reported in individuals with HPS, who generally exhibit easy bruisability and increased bleeding. Desmopressin, pro-coagulants, or platelet transfusion may be used as prophylaxis or treatment for excessive bleeding in patients with HPS. However, response to desmopressin can be variable. Platelets are effective in preventing or treating bleeding in individuals with HPS, but platelets should be transfused judiciously to limit alloimmunization in patients with HPS who are at risk of developing pulmonary fibrosis and may be potential candidates for lung transplantation. The discovery of new genes associated with HPS in people with excessive bleeding and hypopigmentation of unknown etiology may be facilitated by the use of next-generation sequencing or panel-based genetic testing.  相似文献   
68.
The basal ganglia (BG) mediate certain types of procedural learning, such as probabilistic classification learning on the ‘weather prediction task’ (WPT). Patients with Parkinson's disease (PD), who have BG dysfunction, are impaired at WPT‐learning, but it remains unclear what component of the WPT is important for learning to occur. We tested the hypothesis that learning through processing of corrective feedback is the essential component and is associated with release of striatal dopamine. We employed two WPT paradigms, either involving learning via processing of corrective feedback (FB) or in a paired associate manner (PA). To test the prediction that learning on the FB but not PA paradigm would be associated with dopamine release in the striatum, we used serial 11C‐raclopride (RAC) positron emission tomography (PET), to investigate striatal dopamine release during FB and PA WPT‐learning in healthy individuals. Two groups, FB, (n = 7) and PA (n = 8), underwent RAC PET twice, once while performing the WPT and once during a control task. Based on a region‐of‐interest approach, striatal RAC‐binding potentials reduced by 13–17% in the right ventral striatum when performing the FB compared to control task, indicating release of synaptic dopamine. In contrast, right ventral striatal RAC binding non‐significantly increased by 9% during the PA task. While differences between the FB and PA versions of the WPT in effort and decision‐making is also relevant, we conclude striatal dopamine is released during FB‐based WPT‐learning, implicating the striatum and its dopamine connections in mediating learning with FB. Hum Brain Mapp 35:5106–5115, 2014. © 2014 The Authors. Human Brain Mapping Published by Wiley Periodicals, Inc.  相似文献   
69.
The present systematic review and metaanalysis of published observational studies was conducted to assess the health effects of exposure to air pollution on diabetes risk. Online databases were searched through January 2013, and the reference lists of pertinent articles reporting observational studies in humans were examined. Pooled relative risks and 95 % confidence intervals were calculated with a random-effects model. Exposure to air pollution was associated with slight increase in risk of diabetes and susceptibility of people with diabetes to air pollution. These results were consistent between time-series, case-crossover and cohort studies and between studies conducted in North America and Europe. The association between exposure to air pollution and diabetes was stronger for gaseous pollutants than for particulate matter. Our metaanalysis suggests that exposure to air pollution may be a risk factor for diabetes and increase susceptibility of people with diabetes to air pollution.  相似文献   
70.
Mucosal-associated invariant T (MAIT) cells are innate-like T-cells that recognize bacterial riboflavin metabolites. They are present in human blood but are abundant at barrier sites, including the liver, lungs, and kidneys, where they possess a CD69+/CD103+/− tissue-resident phenotype. In renal tissue, MAIT cells likely defend against the ascending uropathogens responsible for urinary tract infections (UTIs), which are common, especially among renal transplant recipients (RTRs). Nevertheless, the functional role for MAIT cells in renal tissue and the influence of renal transplantation on MAIT cells remains unclear. Using multiparameter flow cytometry and the MR1-tetramer, we characterized MAIT cell phenotype and function in healthy renal tissue (n = 6), renal transplants explanted after allograft failure (n = 14) and in blood from healthy controls (n = 20) and RTRs before and 1-year after transplantation (n = 21). MAIT cells in renal tissue constitute a distinct CD69+CD103+/− population that displays typical phenotypic features of tissue-resident T-cells and is skewed toward IL-2, GM-CSF, and IL-17A production upon stimulation. The circulating MAIT cell population was not decreased in number in RTRs pre- or post-transplantation. Tissue-resident MAIT cells in the kidney represent a functionally distinct population. This shows how MAIT cells in the kidney may be involved in the protection against microorganisms.  相似文献   
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