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81.
A new chaos–wavelet approach is presented for electroencephalogram (EEG)-based diagnosis of Alzheimer’s disease (AD) employing a recently developed concept in graph theory, visibility graph (VG). The approach is based on the research ideology that nonlinear features may not reveal differences between AD and control group in the band-limited EEG, but may represent noticeable differences in certain sub-bands. Hence, complexity of EEGs is computed using the VGs of EEGs and EEG sub-bands produced by wavelet decomposition. Two methods are employed for computation of complexity of the VGs: one based on the power of scale-freeness of a graph structure and the other based on the maximum eigenvalue of the adjacency matrix of a graph. Analysis of variation is used for feature selection. Two classifiers are applied to the selected features to distinguish AD and control EEGs: a Radial Basis Function Neural Network (RBFNN) and a two-stage classifier consisting of Principal Component Analysis (PCA) and the RBFNN. After comprehensive statistical studies, effective classification features and mathematical markers were discovered. Finally, using the discovered features and a two-stage classifier (PCA-RBFNN), a high diagnostic accuracy of 97.7% was obtained.  相似文献   
82.
Background: Psoriasis is a non‐contagious disorder that affects the skin as red scaly patches. Although the role of Malassezia species in the pathogenesis of psoriasis is still not fully understood, it is thought that these lipophilic yeasts might be a trigger factor in the exacerbation of psoriatic lesions. Methods: Using culture in a specific medium followed by the polymerase chain reaction‐restriction fragment length polymorphism method, the presence of Malassezia species in the skin of 110 patients with psoriasis was compared with that in a control group of 123 healthy patients. Results: The recovery rate of Malassezia species from the skin of patients with psoriasis was significantly lower than that in the controls. In both psoriatic and healthy skin, Malassezia globosa was isolated as the predominant species. In psoriatic patients, the rate of colonization of Malassezia furfur and Malassezia restricta was almost twice that in the controls, whereas M. globosa was isolated more frequently from healthy individuals than from patients. Conclusions: Considering the higher lipase activity secretion by M. furfur in comparison with other Malassezia species, the enzymatic release of arachidonic acid and its metabolites by M. furfur may exacerbate the inflammatory and hyperproliferative changes observed in psoriasis.  相似文献   
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84.
Lymphoepithelioma-like carcinoma (LELC) of the breast is an exceedingly rare variant of mammary cancer. To our knowledge, only twenty - one cases have been reported in the literature. Diagnosis of this type of mammary carcinoma may be challenging, owing to its rarity and the histopathological similarity to common inflammatory and malignant lesions of the breast mainly granulomatous mastitis, medullary carcinoma, pleomorphic lobular carcinoma, lymphoma and other hematological malignancies. Our case is the 22nd case of lymphoepithelioma-like carcinoma reported in the breast, presenting with a palpable tender mass in a post-menopausal female. Her clinical picture had been mistaken for inflammatory disease. We present our case, with its detailed clinical history, radiological findings, histopathological and immune-histochemical findings along with a review of the literature. Highlighting this type of tumors may help in appropriate diagnosis. Moreover, studying the behavior of these rare neoplasms is essential to expedite treatment for this tumor type.  相似文献   
85.
Hepatitis C virus (HCV) is easily spread among those who share drug injection equipment. Due to the ease of contraction and growing prevalence of HCV in Eastern Europe, the aims of this study focused on describing risky injection practices as well as the prevalence of HCV, HIV and hepatitis B virus (HBV) among people who inject drugs (PWID) who were admitted to public and private drug treatment centres in Turkey from 2012 to 2013. Other aims included identifying correlates of needle sharing and HCV infection. Of the 4694 inpatients who ever injected drugs and the 3914 who injected in the past 30 days, nearly all (98%) reported heroin as their drug of choice, the vast majority reported ever sharing a needle (73.4% and 79.3%), and the mean age at first injection was 23 years. Of current PWID, 51.9% were HCV‐positive, 5.9% were HBV‐positive and only 0.34% of lifetime PWID were HIV‐positive. Predictors of increased needle sharing include younger age, being unemployed, having lesser education and reporting heroin as a drug of choice. Significant predictors of HCV infection included being 40 years or older, receiving treatment in the Mediterranean region of Turkey, reporting heroin as a primary substance, a longer duration of drug use and sharing needles. With this information, it is essential to improve access to clean injection equipment in Turkey, to focus on improving education on clean injection practices and to enhance efforts in testing and treating HCV‐positive PWID.  相似文献   
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87.

Purpose

To assess the effect of high-dose oral thiamine supplements on glucose tolerance in patients with impaired glucose metabolism.

Methods

Twelve hyperglycemic subjects (10 cases of impaired glucose tolerance and 2 new cases of type 2 diabetes) completed this randomized, double-blind trial, where all participants received both placebo and thiamine capsules (3 × 100 mg/day) for 6 weeks in a cross-over manner. The main endpoint was changes in 2-h plasma glucose. Fasting plasma glucose and insulin, 2-h plasma insulin, the hemostatic model assessment of insulin resistance (HOMA-IR), renal function measurement and thiamin status were also evaluated at the commencement and completion of each treatment period.

Results

Thiamine supplementation resulted in significant decrease in 2-h plasma glucose relative to baseline (8.78 ± 2.20 vs. 9.89 ± 2.50 mmol/l, p = 0.004), with no significant change in the placebo arm. Fasting plasma glucose and insulin, and HOMA-IR increased significantly from baseline after 6 weeks in the placebo arm (p = 0.003, p = 0.04 and p = 0.02, respectively). These variables did not change with thiamine supplementation. There were no significant changes in 2-h plasma insulin or renal function marker, within or between arms.

Conclusion/interpretation

Supplementation with high-dose thiamine may prevent deterioration in fasting glucose and insulin, and improve glucose tolerance in patients with hyperglycemia. High-dose thiamine supplementation may prevent or slow the progression of hyperglycemia toward diabetes mellitus in individuals with impaired glucose regulation.  相似文献   
88.
Infections have become as important an event as acute rejection posttransplant for long-term allograft survival. Less invasive biomarkers tested so far predict risk for one event or the other, not both. We prospectively tested blood and urine monthly for 12 months posttransplant from children receiving a kidney transplant. The IDO enzyme pathway was assessed by MS assays using the ratio of product l-kyn to substrate trp. Kyn/trp ratios and blood CD4 T-cell ATP levels were correlated with acute rejection or major infection events or stable group (no events) in the next 30 days. The 25 subjects experienced six discrete episodes of acute rejection in five subjects and 16 discrete events of major infection in 14 subjects (seven BK viruria, six cytomegaloviremia, one EB and cytomegaloviremia, and two transplant pyelonephritis). Mean serum kyn/trp ratios were significantly elevated in the group that experienced acute rejection (p = 0.02). Within-subject analyses revealed that over time, urine kyn/trp ratios showed an increase (p = 0.01) and blood CD4-ATP levels showed a decrease (p = 0.007) prior to a major infection event. These pilot results suggest that a panel of biomarkers together can predict over- or under-immunosuppression, but need independent validation.  相似文献   
89.

Background

Structural neuroimaging MR volumetric changes can predict progression of MCI to AD. Early effective treatment of MCI has been shown to delay institutionalization and improve cognition and behavioral symptoms.

Aim of the work

To evaluate the role of volumetric MRI to identify a pattern of regional atrophy characteristic in differentiation between Alzheimer’s disease, Mild Cognitive Impairment, and Normal elderly control.

Material and methods

The regional ethics committee approved the study and written informed consent was obtained from all participants. Between April 2012 and May 2013, prospective study was conducted on 25 patients (18 males and 7 females) and 15 healthy elderly controls (9 males and 6 females) referred to the Radiodiagnosis Department from the Neuropsychiatry Department that had clinical manifestations of suspected cognitive impairment, we used the Mini Mental State Examination (MMSE) as a measure of general cognitive function and the total learning from the Auditory Verbal Total Learning Test (AVTOT) as a measure of memory performance. One year follow up of patients was done to assess the disease progress.

Results

Twenty-five patients were included in this study {Alzheimer disease (10 cases), MCI (15 cases)} and 15 healthy elderly controls. Mean MMSE scores were significantly lower in patients with Alzheimer’s disease compared with MCI and control cases (P < 0.001). Positive correlation (except left caudate nucleus) between gray matter volume reduction in MCI and AD in relation to elderly control and MMSE score was observed. The Auditory Verbal Learning Test (AVTOT) was significantly lower in patients with Alzheimer’s disease compared with MCI and control cases (P < 0.001). No significant differences were found between groups as regards age, sex, education or dominant hand. Significant gray matter volume reductions were found in both AD and MCI compared to healthy elderly control however no significant differences were found among MCI patients or AD patients. Sensitivity, specificity, PPV and NPV of caudate nucleus and hippocampal volume reduction in AD and MCI in relation to elderly control were higher than entorhinal cortex.

Conclusion

Semi-automated MR volumetric measurements can be used to determine atrophy in hippocampus, caudate nucleus and entorhinal cortex which aided in discrimination of healthy elderly control subjects from subjects with AD and MCI and predict clinical decline of MCI leading to increase the efficiency of clinical treatments, delay institutionalization and improve cognition and behavioral symptoms.  相似文献   
90.
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