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11.
Thrombotic microangiopathy (TMA) is one of the hallmark vascular lesions of antiphospholipid syndrome nephropathy (APSN). These lesions are at high risk of recurrence after kidney transplantation. The complement pathway is thought to be active in this process. We used eculizumab to treat three consecutive kidney transplant recipients with posttransplant TMA due to APSN recurrence that was resistant to plasmapheresis and explored the complement deposition and apoptotic and vascular cell markers on the sequential transplant biopsies. Treatment with eculizumab resulted in a rapid and dramatic improvement of the graft function in all three patients and in improvement of the TMA lesions within the graft. None of these patients had TMA flares after eculizumab was withdrawn. At the time of TMA diagnosis, immunofluorescence studies revealed intense C5b‐9 and C4d depositions at the endothelial cell surface of the injured vessels. Moreover, C5b‐9 colocalized with vessels exhibiting a high rate of apoptotic cells. Examination of sequential biopsies during eculizumab therapy showed that TMA lesions, C4d and apoptotic markers were rapidly cleared but the C5b‐9 deposits persisted for several months as a footprint of the TMA. Finally, we noticed that complement inhibition did not prevent the development of the chronic vascular changes associated with APSN. Eculizumab seems to be an efficient method for treating severe forms of posttransplant TMA due to APSN recurrence. Terminal complement inhibition does not prevent the development of chronic APSN.  相似文献   
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The objectives of this study were to assess long-term graft survival, patient survival, renal function, and acute rejections in de novo kidney transplant recipients, treated with once-daily prolonged-release tacrolimus-based therapy. The study was a 5-year non-interventional prospective follow-up of patients from the ADHERE study, a Phase IV 12-month open-label assessment of patients randomized to receive prolonged-release tacrolimus in combination with mycophenolate mofetil (MMF) (Arm 1) or sirolimus (Arm 2). From 838 patients in the randomized study, 587 were included in the long-term follow-up, of whom 510 completed the study at year 5. At 1 year post-transplant, graft and patient survival rates were 93.0% and 97.8%, respectively, and at 5 years were 84.0% and 90.8%, respectively. Cox proportional hazards analysis showed no association between graft loss, initial randomized treatment arm, donor age, donor type, or sex. The 5-year acute rejection-free survival rate was 77.4%, and biopsy-confirmed acute rejection-free survival rate was 86.0%. Renal function remained stable over the follow-up period: mean ± SD eGFR 4-variable modification diet in renal disease formula (MDRD4) was 52.3 ± 21.6 ml/min/1.73 m2 at 6 months and 52.5 ± 23.0 ml/min/1.73 m2 at 5 years post-transplant. These findings support the role of long-term once-daily prolonged-release tacrolimus-based immunosuppression, in combination with sirolimus or MMF, for renal transplant recipients in routine clinical practice.  相似文献   
14.
Actual Colonic Perforation in Virtual Colonoscopy: Report of a Case   总被引:4,自引:3,他引:4  
Computed tomography colonography, also termed virtual colonoscopy, is a new imaging method to investigate the colon, which may be a potential alternative to the conventional endoscopic colonoscopy in some cases. The high safety profile of this imaging method was considered as an additional advantage of this procedure. A case of colonic perforation in computed tomography colonography is presented, highlighting a potential risk related to this procedure. It is assumed that perforation was the result of overinflation of air into an obstructed colon caused by a lesion at the rectosigmoid junction. Thus, it is suggested that in such cases, air insufflation should be gradual, thereby minimizing the risk of perforation.  相似文献   
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Introduction

Hepatitis E virus (HEV) infection is now recognized to be an emerging autochthonous disease in several countries. There have been several reports of neurological manifestations associated with HEV infections. Immunocompromised patients seem to be particularly vulnerable.

Case report

We report a 73-year-old man who presented with an acute polyradiculopathy and an acute hepatitis. HEV RNA was positive in serum and cerebrospinal fluid. Serum antiganglioside antibodies were also detected. Liver function tests returned to normal rapidly and HEV RNA was undetectable 4 weeks after initial testing. The neurological features improved gradually with the use of intravenous immunoglobulins.

Conclusion

We report a case of Guillain-Barré syndrome related to acute hepatitis E in an immunocompetent patient. The outcome was favorable after intravenous immunoglobulins administration. HEV screening should be systematic in patients who present with an acute polyradiculopathy and abnormal liver function tests.  相似文献   
17.

Background

It has been suggested that identifying phenotypes in chronic obstructive pulmonary disease (COPD) might improve treatment outcome and the accuracy of prediction of prognosis. In observational studies vitamin D deficiency has been associated with decreased pulmonary function, presence of emphysema and osteoporosis, upper respiratory tract infections, and systemic inflammation. This could indicate a relationship between vitamin D status and COPD phenotypes. The aim of this study was to assess the association between vitamin D levels and COPD phenotypes. In addition, seasonality of vitamin D levels was examined.

Methods

A total of 91 patients from a Danish subpopulation of the “Evaluation of COPD Longitudinally to Identify Predictive Surrogate End-points” cohort took part in a biomarker substudy. Vitamin D concentration was measured from blood samples taken at two visits, approximately 6 months apart. The participants were 40–75-year-old patients with COPD and had a smoking history of >10 pack-years.

Results

Fifty-six patients had 25-hydroxyvitamin D measured from blood samples from both visits. In the final model of the multivariate analyses, the factors that were associated with vitamin D deficiency at the first visit were age (OR: 0.89, p = 0.02) and summer season (OR: 3.3, p = 0.03). Factors associated with vitamin D level also at the first visit were age (B: 0.9, p = 0.02) and 6 min walking distance (B: 0.05, p = 0.01).

Conclusion

Vitamin D was not associated with COPD phenotypes and season did not seem to be a determinant of vitamin D levels in patients with moderate to severe COPD.  相似文献   
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20.

Background

Patients with inflammatory bowel disease (IBD) – ulcerative colitis (UC) and Crohn’s disease (CD) have an elevated risk of developing colorectal carcinoma (CRC). Major risk factor in IBD patients is the continuous chronic inflammation leading to development of dysplasia and carcinoma. Nevertheless, other types of non-conventional but suspicious mucosal changes serrated change/dysplasia, NOS and villous hypermucinous change, have also been reported in IBD patients. Preneoplastic potential of these lesions is still not well elucidated.

Aims

The aim of this study was identification of IBD-associated CRCs focusing on finding related precursor lesions in the surgical specimen or in archival biopsy samples followed by a detailed morphological, immunohistochemical and molecular evaluation. For the purpose of the study the mucosal lesions were divided into conventional IBD-associated dysplasia and non-conventional lesions that were merged under a provisory term of putative preneoplastic lesions (PPL).

Methods

A total of 309 consecutive IBD colectomy specimens diagnosed during a 10-year period were reviewed. Detailed morphological evaluation, immunohistochemical analysis of mismatch repair (MMR) proteins, p53 and O6-methylguanine DNA methyltransferase (MGMT) expression and molecular analysis for KRAS, NRAS and BRAF gene mutation were performed in the retrieved CRC cases as well as in the detected dysplasia and PPLs of these patients.

Results

We identified 11 cases of morphologically heterogenous IBD-associated CRCs, occurring in 5 males and 6 females, aged 26–79 years (mean 44 years). A total of 22 mucosal lesions were revealed in 8 CRC patients comprising conventional IBD-associated dysplasia (4 lesions), PPLs as serrated change/dysplasia NOS (11 lesions), villous hypermucinous change (5 lesions), and two true serrated lesions (one sessile serrated adenoma and one traditional serrated adenoma). More than one type of lesion was found in 6 patients. Seven CRC cases harbored mutation of KRAS/NRAS and one case of BRAF. Two patients with KRAS-mutated CRC showed the same mutation in PPL in the same specimen (one serrated change NOS and one TSA with high-grade dysplasia). Similarly, one BRAF-mutated carcinoma case presented the same mutation in serrated change/dysplasia, NOS in the same specimen. Of the CRCs, two showed deficient MMR system profile, six presented with loss of MGMT expression, and six showed aberrant p53 expression. PPLs showed deficient MGMT expression (14 cases) and aberrant p53 (10 cases) as well.

Conclusion

IBD-associated CRCs are very heterogeneous entities. Besides conventional IBD-related dysplasia, other types of mucosal lesions may be associated with long lasting IBD and CRC e.g. villous hypermucinous change and serrated change/dysplasia, NOS. Since these lesions share certain genetic or immunohistochemical changes with the related CRC, a suspicion is raised that these lesions may also have preneoplastic potential. Awareness of these changes is necessary to prevent their missing and under-reporting, and further studies of these lesions should be carried out.  相似文献   
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