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51.
Obscure gastrointestinal bleeding: diagnostic and therapeutic approach   总被引:6,自引:0,他引:6  
Obscure gastrointestinal bleeding (OGIB) is defined as an intermittent or continuous loss of blood in which the source has not been identified after upper endoscopy and colonoscopy. It constitutes a diagnostic and therapeutic challenge for the general internist and the gastroenterologist. This article provides an overview of the etiology, clinical presentation, and diagnostic modalities of OGIB including push enteroscopy, double balloon enteroscopy, wireless capsule endoscopy, enteroclysis, angiography, bleeding scanning with labeled red blood cells, and surgery with intraoperative enteroscopy. Therapeutic modalities including iron replacement, combined hormones, octreotide acetate, therapeutic endoscopy, and surgery are also discussed. In addition, a rational approach to patients with OGIB according to the clinical presentation is presented herein.  相似文献   
52.

Background  

Accurate HER2 testing is of great clinical value for the identification of breast cancer patients who are eligible for trastuzumab therapy. The aim of this study is to review breast carcinomas diagnosed from 2001 to 2007 at a Spanish National Reference Centre for HER2 testing, evaluating the agreement between HER2 immunohistochemical (IHC) tests and fluorescence in situ hybridisation (FISH) tests.  相似文献   
53.
The proportion of peripheral blood mononuclear cells (PBMCs) expressing TNF-alpha and its receptors (TNFR1, TNFR2) and the serum concentrations of its soluble forms were analyzed by FACS and ELISA in the patients with chronic inflammatory demyelinating polyneuropathy (CIDP) and in controls. Elevated levels of TNFR2 were observed on blood T cells in CIDP and idiopathic polyneuropathy. Low levels of TNFR1 were detected on monocytes in the subgroup of patients with CIDP examined after treatment with intravenous immunoglobulin. However, the proliferative activity of PBMCs in CIDP was not influenced by soluble recombinant TNFR1. Our limited data suggested the exact role of TNF-alpha and its receptors need to study further in CIDP, as well as in idiopathic neuropathies.  相似文献   
54.
Abstract:  The purpose of this review was to evaluate the case reports with lymphoproliferative disorders exclusively localized in the allograft transplanted kidney. We also report a rare case of diffuse large B-cell lymphoma originated from the lymphocytes of the recipient with exclusive localization in the kidney allograft. We searched the medical literature for case reports of this condition. We found only 16 cases of lymphoma presenting in the kidney allograft without systemic affectation. The most frequent clinical manifestations were graft dysfunction and fever. In the majority of patients included in this review, the diagnosis was established from the tissue of explanted allograft. Seven patients were diagnosed with B-cell lymphoma, and the relationship with Epstein-Barr virus could only be demonstrated in four patients. However, the outcome was satisfactory in all cases, except in one case in which death was not related with the lymphoma etiology. Health care providers should be aware of this clinical entity and heightened index of suspicion should be used so as not to delay diagnosis and not to lose the allograft.  相似文献   
55.
Although human mucosal leishmaniasis is much more common in Latin America, a few cases that are the result of local transmission occur in Europe. A suspected case of leishmaniasis is usually confirmed by the demonstration of amastigotes in smears, the culture of promastigotes from blood or tissue samples, or the PCR-based demonstration of leishmanial DNA. Biopsies may contain too few parasites to be found positive by microscopy or culture, however, and then a diagnosis may be difficult, especially in regions where human leishmaniasis in general or particular forms of the disease are rarely seen. The aim of the present study was to investigate the histopathological characteristics of three Spanish cases of non-granulomatous mucosal leishmaniasis caused by Leishmania infantum. The hope was that the information collected will help European clinicians diagnose such cases, even when amastigotes cannot be readily demonstrated.  相似文献   
56.
PURPOSE: As an important connection within the limbic system, considerable attention has been paid to thalamic pathology in temporal lobe epilepsy (TLE). Magnetic resonance imaging (MRI) volumetric studies have yielded variable results and have largely been focused on TLE with mesial temporal sclerosis (TLE+). Diffusion tensor imaging (DTI) provides unique information on microstructure based on the measurement of water diffusion. To date, DTI properties of thalamus have not been well characterized in adult TLE patients with unilateral MTS or without MTS (TLE-). The purpose of this study was to investigate the status of thalamic integrity by using DTI as well as volumetric MRI in adult TLE+ and TLE- patients. METHOD: In 17 unilateral TLE+ patients, 10 TLE- patients and 26 controls, the thalamus was segmented by using an automated atlas-based method. Mean diffusivity (MD), fractional anisotropy (FA) and volume were then quantified from DTI and 3D T1-weighted scans. RESULTS: No significant changes were found in either DTI parameters or volume of thalamus in TLE- patients, as compared to healthy controls. However, both DTI parameters and MRI volumetry showed bilateral thalamic pathology in TLE+ patients, as compared to healthy controls. Also, TLE+ patients showed significant reduction of thalamic volume as compared to TLE- patients. In addition, thalamic FA ipsilateral to seizure focus showed significant correlation with age at onset of epilepsy in TLE+ patients. CONCLUSION: Our finding demonstrates bilateral pathology of thalamus in unilateral TLE+ patients. The discrepancy in thalamic pathology between TLE+ and TLE- patients suggests that along with differences in mesial temporal pathology, TLE+ and TLE- have unique extratemporal structural abnormalities.  相似文献   
57.
The effect of an aqueous fraction from the bulbs of Allium sativum (GE) was investigated in toad skin. When added to the inner (serosal) solution, GE caused a maximal reversible reduction of the transepithelial potential difference and short circuit current of 38% and 45%, respectively. When added to the outer (mucosal) solution, the effect was only partially reversible. Isaacson's amiloride test showed that GE decreased sodium potential (ENa.) and sodium conductance (GNa.). The net Na+ flux decreased due principally to a fall in Na+ flux in the active direction. GE decreased Na(+)-K+ ATPase activity in vitro. Partial replacement of sodium by choline in the outer solution reduced the effect of GE on the skin and substitution of normal Ringer's solution with isethionate Ringer's solution in the outer solution significantly enhanced the effect of GE on the skin. These results indicate that GE decreases active Na transport in the toad skin.  相似文献   
58.
We have isolated a monoclonal antibody (150) that recognizes a phosphorylation epitope on the microtubule-associated protein (MAP) 1B. Immunoblot analysis of the developing rat central nervous system shows that monoclonal antibody 150 is directed against a protein of ∼325 kDa (MAP 1B) that copolymerizes with microtubules through successive cycles of temperature-dependent assembly and disassembly. Furthermore, immunoprecipitated MAP 1B contains the epitope recognized by monoclonal antibody 150. Removal of phosphate from blotted proteins using alkaline phosphatase abolishes the binding of monoclonal antibody 150 to MAP 1B, indicating that the epitiope is phosphorylated. In the developing rat nervous system, immunohistochemistry with monoclonal antibody 150 shows that the phosphorylation epitope on MAP 1B is transiently expressed in growing axons but not in dendrites. For instance, in the neonatal rat cerebellum, the parallel fibres of granule cells are stained only during elongation and not after synaptogenesis. The monoclonal antibody 150 epitope is also transiently expressed in radial glial fibres and in certain cell nuclei. All immunostaining of sections with monoclonal antibody 150 was completely abolished by alkaline phosphatase treatment. These observations and previous ones made by us in cell culture (Mansfield et al., J. Neurocytol. , 20 , 654 – 666, 1991) suggest that the phosphorylation epitope on MAP 1B recognized by monoclonal antibody 150, which has not been previously detected in vivo , may be important in axonogenesis.  相似文献   
59.
3.1 Scholarship and the university   总被引:1,自引:1,他引:0  
Universities now exist in an environment of increasing accountability for their academic performance, both in teaching and research. Dental schools are expected to meet the academic expectations of their parent university and, in addition, to contribute to the health-care needs of the community. Individual staff members must achieve collectively the performance targets required of their school and individually must develop skills and expertise in their academic and clinical activities to merit tenure and promotion. This discussion examines the issues which impact on current problems of recruitment and retention of academic staff in dental schools internationally. The essential issue is career development in a manner which maintains the values that will ensure the credibility of dentistry as a scientifically based discipline and profession, while balancing the achievable academic needs with the added demands of achieving specialist clinical skills. Central to this balance is recognition that scholarship, which provides the bridge between research and teaching, can be broadly defined and that different individuals can be scholarly in a range of ways. Increasingly, schools are recognizing the importance of providing structured opportunities and guidance for career development of younger staff and of the need for flexibility in their criteria for tenure and promotion, recognizing that a diversity of individual strengths and teamworking are necessary both for the collective performance of the institution and the morale and development of the individual.  相似文献   
60.
OBJECTIVE: Although the first pulmonary autograft operations were performed in Spain in 1991, this procedure has gained substantial interest and has been consolidated since 1997. The establishment of the Spanish Registry of the Ross Operation pretends to evaluate the results of this option in aortic valve disease patients in our setting. METHODS: In a yearly fashion, the cardiac surgery departments in Spain currently performing this intervention send data from new patients or follow-ups to the reference center. Preoperative, intraoperative and postoperative data are included in the registry, with special attention to morbidity, mortality, autograft and homograft dysfunction and need for reintervention. RESULTS: Since February 1991 to May 2002, 169 patients have been treated with this technique. The most prevalent aortic disease was regurgitation (72; 42.59%), congenital being the most frequent etiology (108; 63.9%). Four (2.36%) patients required intraoperative aortic counterpulsation. Operative mortality was 2.36% (n=4). Follow-up is 98.7% complete, with an average of 36.08+/-31.09 months (range 1-135), 84 patients (49.7%) were followed for more than 2 years. The autograft remains competent or with trivial to mild regurgitation in 161 patients (95.6%), presenting two (1.18%) with severe regurgitation. The homograft was normal or with mild stenosis in 159 patients (94.07%), presenting five (2.95%) with severe stenosis. Three (1.77%) required reintervention (surgical or interventional) on the right ventricular outflow tract and four (2.36%) required autograft replacement for a mechanical prosthesis. Actuarial survival is 95.99+/-1.65% at 36 months, remaining 92.44+/-2.55% free from reintervention in the same period. CONCLUSIONS: The Ross operation is an increasingly popular surgical option in Spain, and although the number of patients and length of follow-up are still limited, initial results are at least as good as those reported internationally. It is important to continue a close follow-up of these patients to assess the long-term function of auto and homograft. With the available data, we believe that this therapeutic approach is a valid option for selected groups of patients with surgical aortic valve disease in Spain.  相似文献   
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