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51.
Severe cognitive impairment involving multiple cognitive domains can occur early during the course of multiple sclerosis (MS). We investigated resting state functional connectivity changes in large‐scale brain networks and related structural damage underlying cognitive dysfunction in patients with early MS. Patients with relapsing MS (3–5 years disease duration) were prospectively assigned to two groups based on a standardized neuropsychological evaluation: (1) cognitively impaired group (CI group, n = 15), with abnormal performances in at least 3 tests; (2) cognitively preserved group (CP group, n = 20) with normal performances in all tests. Patients and age‐matched healthy controls underwent a multimodal 3T magnetic resonance imaging (MRI) including anatomical T1 and T2 images, diffusion imaging and resting state functional MRI. Structural MRI analysis revealed that CI patients had a higher white matter lesion load compared to CP and a more severe atrophy in gray matter regions highly connected to networks involved in cognition. Functional connectivity measured by integration was increased in CP patients versus controls in attentional networks (ATT), while integration was decreased in CI patients compared to CP both in the default mode network (DMN) and ATT. An anatomofunctional study within the DMN revealed that functional connectivity was mostly altered between the medial prefrontal cortex (MPFC) and the posterior cingulate cortex (PCC) in CI patients compared to CP and controls. In a multilinear regression model, functional correlation between MPFC and PCC was best predicted by PCC atrophy. Disconnection in the DMN and ATT networks may deprive the brain of compensatory mechanisms required to face widespread structural damage. Hum Brain Mapp 35:4706–4717, 2014. © 2014 Wiley Periodicals, Inc .  相似文献   
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A causative association was recently demonstrated between homozygous TREM2 mutations and frontotemporal dementia (FTD)-like syndrome and between heterozygous TREM2 exon2 genetic variations and late-onset Alzheimer's disease (AD). The objective of this study was to evaluate whether heterozygous TREM2 genetic variations might be associated to the risk of FTD. TREM2 exon 2 was sequenced in a group of 1030 subjects—namely, 352 patients fulfilling clinical criteria for FTD, 484 healthy control subjects (HCs), and 194 patients with AD. The mutation frequency and the associated clinical characteristics were analyzed. We identified 8 missense and nonsense mutations in TREM2 exon 2 in 24 subjects. These mutations were more frequent in patients with FTD than in HCs (4.0% vs. 1.0%, p = 0.005). In particular, TREM2 Q33X, R47H, T66M, and S116C mutations were found in FTD and were absent in HCs. These mutations were associated with either the semantic variant of primary progressive aphasia or the behavioral variant FTD phenotypes. The FTD and AD groups were not significantly different with regard to TREM2 genetic variation frequency (AD: 2.6%, p = 0.39). Heterozygous TREM2 mutations modulate the risk of FTD in addition to increasing susceptibility to AD. Additional studies are warranted to investigate the possible role of these mutations in the pathogenesis of neurodegenerative disorders.  相似文献   
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Looking to the sustained psoriatic arthritis (PsA) joint as a model of local human inflammation, this study was designed to assess the T lymphocyte signal transduction pathways potentially involved in this chronic immune-mediated inflammatory process, as characterized by direct ex vivo analysis of T helper (Th)-17 T effector (Teff) cell phenotypes in synovial fluid (SF) and peripheral blood (PB) of clinically active PsA patients. The reverse-phase protein arrays (RPPA) technique was employed to identify STAT3, STAT1, JAK1, JAK2, PKCδ and ERK1/2 phosphoprotein levels on total T cell lysates in SF samples of PsA patients. Frequencies of T CD4+IL-17A-F+ and T CD4+IL-23R+ Th17 cells were quantified in SF and matched PB of PsA patients by flow cytometry and compared with PB of healthy controls (HC). Increased levels of JAK1, STAT3, STAT1 and PKCδ phosphoproteins were found in SF T cells of PsA patients, compared with PB of HC. The expansion of T CD4+IL-17A-F+ cells, as well as of T CD4+ cells expressing IL-23Rp19 (T CD4+ IL-23R+), considered as the pathogenic phenotype of effector Th17 cells, was found to be confined to the joints of PsA patients, as the frequencies of both populations were significantly higher in SF than in matched PB, or in PB of HC. In conclusion, T lymphocyte signal transduction pathway mapping revealed an enhanced activation of JAK1/STAT3/STAT1 and PKCδ phosphoproteins that may drive the local inflammatory process, characterized by the in vivo expansion of T CD4+IL-17A-F+ and T CD4+IL-23R+ Th17 Teff cells in SF of clinically active joints of PsA patients.  相似文献   
55.
Dose-dense adjuvant chemotherapy is standard of care in high-risk early breast cancer patients. However, its role in HER2-positive patients is still uncertain. In this exploratory analysis of the GIM2 trial, we investigated the efficacy of dose-dense chemotherapy in HER2-positive breast cancer patients with or without exposure to trastuzumab. In the GIM2 trial, node-positive early breast cancer patients were randomized to receive four cycles of (fluorouracil)epirubicin/cyclophosphamide followed by four cycles of paclitaxel administered every 2 (dose-dense) or 3 (standard-interval) weeks. After approval of adjuvant trastuzumab, protocol was amended in April 2006 to allow use of trastuzumab for 1 year after chemotherapy completion in HER2-positive patients. The efficacy of dose-dense chemotherapy in terms of disease-free survival (DFS) and overall survival (OS) was assessed according to HER2 status and trastuzumab use. Out of 2,003 breast cancer patients, HER2 status was negative/unknown in 1,551 patients; among the 452 patients with HER2-positive breast cancer, chemotherapy alone or followed by trastuzumab was given to 320 and 132 patients, respectively. Median follow-up was 8.1 years. No significant interaction between HER2 status, trastuzumab use and chemotherapy treatment was observed for both DFS (p = 0.698) and OS (p = 0.708). Nevertheless, there was no apparent benefit in the HER2-positive group treated with trastuzumab (DFS: HR, 0.99; 95% CI 0.52–1.89; OS: HR, 0.95; 95% CI 0.37–2.41). Although dose-dense chemotherapy was associated with a significant survival improvement in high-risk breast cancer patients, its benefit appeared to be smaller (if any) in patients with HER2-positive disease who received adjuvant trastuzumab.  相似文献   
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Williams syndrome (WS) is a rare, multisystemic genomic disorder showing a high prevalence of impaired glucose metabolism in adulthood. The reason for this association is unknown, though hemizygosity for genes mapping to the WS chromosome region has been implicated. Twenty‐two Italian young adults with WS (13 females, 9 males) were studied. A 75 g oral glucose tolerance test (OGTT) was performed and β‐cell function was estimated with Homeostasis Model Assessment (HOMA)‐B%, Insulinogenic Index, and corrected insulin response whereas insulin sensitivity was assessed with HOMA‐Insulin Resistance Index, Quantitative Insulin Check Index, and composite Insulin Sensitivity Index. One patient had known diabetes mellitus (DM), whereas impaired glucose tolerance (IGT) was diagnosed in 12 patients and DM in one (63.6% prevalence of impaired glucose metabolism). IGT patients were more insulin resistant than those with normal glucose tolerance (NGT), whereas β‐cell function was unchanged or increased. Islet autoimmunity was absent. Logistic regression showed that impaired glucose metabolism was not associated with age, body mass index (BMI), or family history of DM. β‐cell function, insulin sensitivity, and post‐load insulin levels did not differ between WS patients with NGT and healthy controls comparable for gender, age, and BMI, though WS–NGT patients had higher post‐load glucose values. These data confirm the high prevalence of impaired glucose metabolism in WS young adults, thus suggesting the need for screening these patients with OGTT. IGT is associated with reduced insulin sensitivity, but not with impaired β‐cell function, islet autoimmunity, and traditional risk factors for type 2 DM. © 2013 Wiley Periodicals, Inc.  相似文献   
59.
Viral hepatitis is a significant health problem worldwide,associated with morbidity and mortality.Hepatitis B,C,D,and occasionally E viruses(HBV,HCV,HDV,and HEV)can evolve in chronic infections,whereas hepatitis A virus(HAV)frequently produces acute self-limiting hepatitis.In the last years,different studies have been performed to introduce new antiviral therapies.The most important goal in the treatment of viral hepatitis is to avoid chronic liver disease and complications.This review analyzes currently available therapies,in particular for viruses associated with chronic liver disease.The focus is especially on HBV and HCV therapies,investigating new drugs already introduced in clinical practice and clinical trials.We also describe new entry inhibitors,developed for the treatment of chronic HDV and HBV and currently available treatments for HEV.The last drugs introduced have shown important efficacy in HCV,with achievable target HCV elimination by 2030.Concurrently,renewed interest in curative HBV therapies has been registered;current nucleotide/nucleoside analogs positively impact liver-related complications,ensuring high safety and tolerability.Novel approaches to HBV cure are based on new antivirals,targeting different steps of the HBV life cycle and immune modulators.The improved knowledge of the HDV life cycle has facilitated the development of some direct-acting agents,as bulevirtide,the first drug conditionally approved in Europe for HDV associated compensated liver disease.Further studies are required to identify a new therapeutic approach in hepatitis E,especially in immunosuppressed patients.  相似文献   
60.
Journal of Thrombosis and Thrombolysis - Anticoagulant therapy has undergone a significant change since direct oral anticoagulants (DOACs) introduction. Their obvious advantages including the fixed...  相似文献   
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