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BACKGROUND AND OBJECTIVES: The Hancock II bioprosthesis is a second-generation porcine valve xenograft treated with the detergent sodium dodecyl sulphate (T6) to retard calcification. The aim of this investigation was to study the gross and microscopic features in Hancock II explants to assess the structural changes occurring with time. METHODS: Among 1382 Hancock II bioprostheses (701 isolated aortic, 421 isolated mitral, 130 double) implanted from 1983 to 1997 in 1252 patients, 22 (16 mitral, 6 aortic) were removed at reoperation until 1999 and were available for pathological investigation: infective endocarditis occurred in 5 and structural deterioration in 8, whereas in the remaining 9 xenografts reoperation was performed for nonstructural valve deterioration (paravalvular leak in 4 and prophylactic replacement in 5). Morphological investigation consisted of gross examination and x-ray, histologic, immunohistochemistry, electron microscopic, and atomic absorption spectroscopic examination. RESULTS: The cause of structural valve deterioration was dystrophic calcification in 4 cases (1 aortic, 3 mitral; range of time graft was in place, 101 to 144 months), non-calcium-related tears in 3 cases (all mitral, range 121 to 163 months), and commissural dehiscence in 1 (aortic, range 156 months). Five of the nonstructural valve deterioration explants (range 42 to 122 months) showed only pinpoint mineralization at the commissures. Mean calcium content in nonstructural deterioration explants was 14.70 +/- 22.33 versus 99.11 +/- 81.52 mg/g in explants with structural valve deterioration. Electron microscopic examination showed early nuclei of mineralization mostly consisting of calcospherulae upon cell debris. Local or diffuse lipid insudation was observed in all but 2 explants and consisted of cholesterol clefts, lipid droplets, and lipid-laden macrophages featuring foam cells. The lipid insudation was the most plausible cause of tearing in 2 explants. CONCLUSIONS: These pathologic findings support the clinical results of a delayed occurrence of structural failure of Hancock II bioprostheses and a mitigation of mineralization by the anti-calcification treatment. However, other factors such as lipid insudation may come into play in the long term.  相似文献   
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Low respiratory tract infections (LRTI) represent the leading infectious cause of death worldwide and account for substantial use of healthcare resources. Physicians must adopt practices focused on improving outcomes and serum biomarker can help them in the management of patients with LRTI. Several studies have been carried out or are currently ongoing to evaluate the role of various biomarkers for the differential diagnosis, definition of prognosis, treatment and duration of antibiotic therapy in respiratory infections. The objective of this position paper of the Italian Society of Respiratory Diseases (SIMER) is to provide evidence-based recommendations for the use of biomarkers in routine clinical practice in the management of adult patients with LRTI. These guidelines capture the use of biomarkers both outside and inside the hospital, focused on community-acquired pneumonia, acute exacerbations of chronic obstructive pulmonary disease, hospital-acquired and ventilator-acquired pneumonia.  相似文献   
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Background and objectives: Sexual dysfunction is very common in patients with chronic kidney disease (CKD), but treatment options are limited. The benefits and harms of existing interventions for treatment of sexual dysfunction were assessed in patients with CKD.Design, setting, participants, & measurements: MEDLINE (1966 to December 2008), EMBASE (1980 to December 2008), and the Cochrane Trial Registry (Issue 4 2008) were searched for parallel and crossover randomized and quasi-randomized trials. Treatment effects were summarized as mean differences (MD) or standardized mean difference (SMD) with 95% confidence intervals (CI) using a random effects model.Results: Fourteen trials (328 patients) were included. Phosphodiesterase-5 inhibitors (PDE5i) compared with placebo significantly increased the overall International Index of Erectile Function-5 (IIEF-5) score (three trials, 101 patients, MD 1.81, 95% CI 1.51 to 2.10), all of its individual domains, and the complete 15-item IIEF-5 (two trials, 80 patients, MD 10.64, 95% CI 5.32 to 15.96). End-of-treatment testosterone levels were not significantly increased by addition of zinc to dialysate (two trials, 22 patients, SMD 0.19 ng/dl, 95% CI −2.12 to 2.50), but oral zinc improved end-of-treatment testosterone levels. There was no difference in plasma luteinizing and follicle-stimulating hormone level at the end of the study period with zinc therapy.Conclusions: PDE5i and zinc are promising interventions for treating sexual dysfunction in CKD. Evidence supporting their routine use in CKD patients is limited. There is an unmet need for studying interventions for male and female sexual dysfunction in CKD considering the significant disease burden.Sexual dysfunction is a set of disorders characterized by physical and psychologic changes that result in the inability to perform satisfactory sexual activities. The condition has been found to be significantly more common in men and women with chronic kidney disease (CKD) than in the general population (1). Men with CKD frequently suffer from reduced libido, erectile dysfunction, and difficulty reaching orgasm (2). Approximately 50% of male predialysis CKD patients and 80% of male dialysis patients have erectile dysfunction (36). Moreover, the prevalence of erectile dysfunction in male dialysis patients has been found to increase with age (63% <50 years versus 90% ≥50 years) (3). Similar results have been reported in women with CKD, with 55% of female dialysis patients reporting difficulty with sexual arousal (2). Dysmenorrhea, delayed sexual development, impaired vaginal lubrication, dyspareunia, and difficulties in reaching orgasm are also frequently observed (7,8).Multiple factors contribute to the frequent occurrence of sexual dysfunction in CKD patients, including hormonal disturbances (such as hyperprolactinemia, hypogonadism in males, and changes in hypothalamic-pituitary function in women) (9), anemia (10), CKD mineral and bone disorder (4), psychosocial factors (such as depression, anxiety, poor self-esteem, social withdrawal, marital discord, body image issues, fear of disability and death, loss of employment, and financial difficulties) (2,11,12), autonomic neuropathy (13), medications (including antihypertensives, antidepressant, and histamine receptor blockers) (2), and comorbid illness (such as diabetes mellitus, cardiovascular disease, and malnutrition) (2,14). Sexual dysfunction is inversely associated with GFR (7) and is improved after renal transplantation (15,16), suggesting that CKD per se may contribute to sexual dysfunction in these patients (15).Studies have also identified significant associations between sexual dysfunction in CKD patients and depression (8,17), impaired quality of life (8,17,18), and adverse cardiovascular outcomes (19). Effective treatment of sexual dysfunction in CKD patients may therefore potentially lead to improvement in these patient-level outcomes, although a causal link has not been definitively established (18).Therapies that have been used to treat sexual dysfunction include phosphodiesterase-5 inhibitors (PDE5i), intracavernosal injections, intraurethral suppositories, hormonal therapy, mechanical devices, and psychotherapy. Although many clinical trials and reviews have explored the role of these interventions for sexual dysfunction in nonuremic patients (2024), the effectiveness and safety of these interventions in patients with CKD have not yet been studied thoroughly. Therefore, we aimed to evaluate the benefits and harms associated with various interventions for sexual dysfunction in patients with CKD.  相似文献   
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SERPIN B3/B4, members of the serpin superfamily, are fundamental for the control of proteolysis through a known inhibitory function of different proteases. Several studies have documented an important role of SERPIN B3 in the modulation of inflammation, programmed cell death and fibrosis. To confirm the role of SERPIN B3 in lung fibrosis and overall investigate its influence on epithelial dysfunction, a stratified controlled trial randomly assigning bleomycin (BLM) treatment was performed on both SERPIN B3 transgenic (TG) and wild-type (WT) mice. TG and WT animals were killed 48?h (group T48?h) and 20 days (group T20d) after BLM treatment. Lung fibrosis was assessed by histology and hydroxyproline measurement. Architectural remodeling, inflammation, epithelial apoptosis and proliferation were quantified. Moreover, the profibrogenetic cytokine transforming growth factor (TGF)-β, cathepsin K, L and S were also investigated. No significant differences were observed between TG and WT mice of group T48?h in any parameters. In group T20d, less inflammation and a significant increase in epithelial proliferation were detected in treated TG than WT mice despite a similar apoptotic index, thus resulting in a different apoptosis/proliferation imbalance with a significant gain of epithelial proliferation. Moreover, TG mice showed higher TGF-β expression and more extended fibrosis. General linear model analysis, applied on morphological data, showed that interaction between SERPIN B3 expression and treatment was mainly significant for fibrosis. This study provides in vivo evidence for a role of SERPIN B3 in inhibiting inflammation and favoring epithelial proliferation with increased TGF-β secretion and thus the likelihood of consequent fibrogenesis.  相似文献   
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Chemotherapy-induced peripheral neurotoxicity (CIPN) is a major side effect of several antineoplastic drugs. However, despite its clinical importance, there is no agreement as to the best way to assess the severity and changes in CIPN. We have previously demonstrated a correlation between the severity of CIPN, assessed using the Total Neuropathy Score (TNS) or its reduced versions, and several common toxicity scales. In this study, we investigated two series of patients (total number = 173) who were evaluated at baseline and during chemotherapy with the TNS (n= 122) or the TNSc (the TNS version based exclusively on the clinical evaluation of the patients, n= 51) and with the National Cancer Institute-Common Toxicity Criteria (NCI-CTC) 2.0, with the aim of comparing the sensitivity to the changes in CIPN severity. In both series, the TNS and the TNSc had a significant correlation with the NCI-CTC in scoring the severity of CIPN, confirming the results of previous studies. Moreover, both the TNS and the TNSc showed a higher sensitivity to CIPN changes. We, therefore, propose the TNSc as a reliable method for assessing not only the severity but also the changes in CIPN.  相似文献   
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The outflow venovenous anastomosis represent a crucial aspect during orthotopic liver transplantation (OLT) with inferior vena cava (IVC) preservation. The modified Belghiti liver hanging maneuver applied to the last phase of hepatectomy, lifting the liver, provides a better exposure of the suprahepatic region and allows easier orthogonal clamping of the three suprahepatic veins with a minimal portion of IVC occlusion. The outflow anastomosis constructed with a common cloacae of the three native suprahepatic veins is associated with a lower incidence of graft related venous outflow complications. The procedure planned in 120 consecutive OLT was achieved in 118 (99%). The outflow anastomosis was constructed on the common cloaca of the three hepatic veins in 111/120 cases (92.5%). No major complications were observed (bleeding during tunnel creation, graft outflow dysfunction, etc) except in one patient with acute Budd-Chiari, who successfully underwent retransplantation.  相似文献   
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