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71.
BACKGROUND: The efficacy of second-line chemotherapy for patients with recurrent or progressive oligodendroglial tumors is limited. In the current study, the authors investigated the use of carboplatin as a second-line chemotherapeutic agent against these types of tumors. METHODS: Twenty-three patients with recurrent or progressive oligodendrogliomas or oligoastrocytomas after first-line PCV (procarbazine, lomustine, and vincristine) chemotherapy were enrolled in a single-institution Phase II study of second-line carboplatin chemotherapy. All patients had undergone surgery, and most also had undergone conventional radiotherapy. Carboplatin was administered at a dose of 560 mg/m2 intravenously every 4 weeks. Responses were evaluated according to conventional criteria, based on magnetic resonance imaging (MRI) findings. RESULTS: Three of 23 patients (13%) had partial responses, with neurologic improvement. Twelve patients (52%) had stable disease; in 2 of these 12 patients, a minor response was seen on MRI. Eight patients (35%) had progressive disease. The median time to tumor progression was 3 months for all patients and 9 months for patients who experienced responses to treatment. Progression-free survival rates at 6 and 12 months were 34.8% and 8.7%, respectively. Among the salvage treatment plans followed after carboplatin chemotherapy were supportive care alone, radiotherapy, third-line chemotherapy, and reoperation. The median survival duration from the start of carboplatin administration was 16 months. Myelotoxicity was severe, with Grade 3 or 4 thrombocytopenia in 60% of patients and Grade 3 or 4 neutropenia in 48% of patients. CONCLUSIONS: When administered according to a monthly schedule, carboplatin exhibited modest activity in adult patients with recurrent or progressive oligodendroglioma or oligoastrocytoma who experienced treatment failure after PCV chemotherapy; the current treatment regimen also was associated with severe toxicity. Further improvement of second-line chemotherapy for the patient group examined in the current study is necessary.  相似文献   
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This retrospective study of cardiac surgical patients with normal serum creatinine who developed acute renal failure requiring artificial renal support was undertaken to (1) determine the prevalence of acute renal failure and hospital mortality in this subgroup, (2) identify the independent predictors of early mortality, and (3) determine long-term survival and prognosis.  相似文献   
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We here investigated the effect of the catecholaminergic neurotransmitter dopamine (DA), on the release of two major inflammatory effectors, TNF-alpha and nitric oxide, in rat astroglia-enriched cultures stimulated with the bacterial endotoxin lipopolysaccharide (LPS). Upon LPS challenge, we observed a dramatic increase in the culture medium of the TNF-alpha protein, an effect thereafter followed by an increase of nitric oxide synthase type 2 (NOS2) mRNA and, at later times, of nitrite accumulation, an index of nitric oxide (NO) production. DA substantially inhibited the release of TNF-alpha and NO evoked by LPS, an effect not mimicked by selective agonists nor prevented by selective antagonists of the DA receptors. The inhibitory effects of DA were mimicked by noradrenalin and isoproterenol and fully reverted by propranolol, a selective antagonist of the beta-adrenergic receptors. In addition, selective antagonists of beta-adrenergic receptor type 1 (metoprolol) and type 2 (ICI-118,551) counteracted the inhibitory effects of DA on LPS-induced TNF-alpha and NO release. Accordingly, agents capable of elevating intracellular cyclic 3',5'-adenosine monophosphate (cAMP), such as forskolin and dibutyryl-cAMP, mimicked DA inhibitory effects on LPS-evoked accumulation of TNF-alpha and nitrite. These data, consistent with a role of DA as local modulator of glial inflammatory responses, uncover the existence of an interaction between DA and heterologous beta-adrenergic receptors in astroglial cells.  相似文献   
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Recent evidence indicates that neural stem cell properties can be found among a mammalian skin-derived multipotent population. A major barrier in the further characterization of the human skin-derived neural progenitors is the inability to isolate this population based on expression of cell surface markers. Our work has been devoted to purified human skin-derived stem cells that are capable of neural differentiation, based on the presence or absence of the AC133 cell surface marker. The enriched skin-derived AC133(+) cells express the CD34 and Thy-1 antigens. These cells cultured in a growth medium containing epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF) proliferate, forming spheres, and differentiate in vitro into neurons, astrocytes, and rarely into oligodendrocytes. Single cells from sphere cultures initiated from human purified AC133(+) cells were replated as single cells and were able to generate new spheres, demonstrating the self-renewing ability of these stem cell populations. Brain engraftment of cells obtained from human purified AC133(+)-derived spheres generated different neural phenotypes: immature neurons and a most abundant population of well differentiated astrocytes. The AC133-derived astrocytes assumed perivascular locations in the frontal cortex. No donor-derived oligodendrocytes were found in the transplanted mouse brains. Several donor small, rounded cells that expressed endothelial markers were found close to the host vessel and near the subventricular zone. Thus, mammalian skin AC133-derived cells behave as a multipotent population with the capacity to differentiate into neural lineages in vitro and, prevalently, endothelium and astrocytes in vivo, demonstrating the great plasticity of these cells and suggesting potential clinical application.  相似文献   
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OBJECTIVE: The aim of this study is to evaluate in a cohort of patients with impaired left ventricular (LV) function and ischemic mitral valve regurgitation (MVR), the effects of on-pump/beating heart versus conventional surgery in terms of postoperative mortality and morbidity and LV function improvement. MATERIALS AND METHODS: Between January 1993 and February 2001, 91 patients with LVEF between 17% and 35% and chronic ischemic MVR (grade III-IV), underwent MV repair in concomitance with coronary artery bypass grafting (CABG) Sixty-one patients (Group I) underwent cardiac surgery with cardioplegic arrest, and 30 patients (Group II) underwent beating heart combined surgery. Aortic valve insufficiency was considered a contraindication for the on-pump/beating heart procedure. Mean age in Group I was 64.4 +/- 7 years and in Group II, 65 +/- 6 years (p = 0.69). RESULTS: The in-hospital mortality in Group I was 8 (13%) patients versus 2 (7%) patients in Group II (p > 0.1). The cardiopulmonary bypass (CPB) time was significantly higher in Group I (p < 0.001). In Groups I and II, respectively (p > 0.1), 2.5 +/- 1 and 2.7 +/- 0.8 grafts per patient were employed. Perioperative complications were identified in 37 (60.7%) patients in Group I versus 10 (33%) patients in Group II (p = 0.025). Prolonged inotropic support of greater than 24 hours was needed in 48 (78.7%) patients (Group I) versus 15 (50%) patients (Group II) (p = 0.008). Postoperative IABP and low cardiac output incidence were significantly higher in Group I, p = 0.03 and p = 0.027, respectively. Postoperative bleeding greater than 1000 mL was identified in 24 patients (39.4%) in Group I versus 5 (16.7%) in Group II (p = 0.033). Renal dysfunction incidence was 65.6% (40 patients) in Group I versus 36.7% (11 patients) in Group II (p = 0.013). The echocardiographic examination within six postoperative months revealed a significant improvement of MV regurgitation fraction, LV function, and reduced dimensions in both groups. The postoperative RF was significantly lower in Group II patients 12 +/- 6 (%) versus 16 +/- 5.6 (%) in Group I (p = 0.001). The 1, 2, and 3 years actuarial survival including all deaths was 91.3%, 84.2%, and 70% in Group I and 93.3%, 87.1%, and 75% in Group II (p = ns). NYHA FC improved significantly in all patients from both groups. CONCLUSION: We conclude that patients with impaired LV function and ischemic MVR may undergo combined surgery with acceptable mortality and morbidity. The on/pump beating heart MV repair simultaneous to CABG offers an acceptable postoperative outcome in selected patients.  相似文献   
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The natural history of asymptomatic IgM monoclonal gammopathies (MG) and variables predicting evolution to symptomatic lymphoproliferative disorders were investigated in 452 patients diagnosed from 1975 to 2001. Univariate and multivariate Cox models were used to identify possible predictors of disease progression. At a median follow-up of 49 months (range, 12 to 233), 41 cases (9.1%) evolved to symptomatic Waldenstrom's macroglobulinemia (n = 36), non-Hodgkin's lymphoma (n = 2), B-cell chronic lymphocytic leukemia (n = 1), IgM multiple myeloma (n = 1), and primary amyloidosis (n = 1); the median interval from diagnosis was 53 months (range, 12 to 154). The cumulative probabilities of transformation into a symptomatic lymphoproliferative disease at 5 and 10 years were 8% (95% confidence interval [CI], 6% to 12%) and 21% (95% CI, 16% to 29%), respectively. At univariate analysis, monoclonal component size and hemoglobin level as continuous parameters, lymphocytosis (>4 x 10(9)/L), bone marrow lymphoplasmacytoid infiltration (>10%), erythrocyte sedimentation rate (>40 mm/h), and detectable Bence Jones proteinuria were significantly related with evolution probability. At multivariate analysis, paraprotein level (P <.0001), hemoglobin level (P <.05), and lymphocytosis (P <.0001) independently predicted malignant evolution (P <.0001). In conclusion, patients with asymptomatic IgM-MG showing hematological features predictive of progression should be carefully monitored in view of an early treatment of the disease.  相似文献   
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BACKGROUND: HIV-infected adults with lipodystrophy, characterized by excess accumulation of intra-abdominal adipose tissue (IAT), showed impaired growth hormone (GH) secretion. Data are lacking in paediatric lipodystrophy with the same features. METHODS: Twenty-five pubertal HIV-infected children were assessed for GH response (GH-AUC(0-120 min)) to arginine + GHRH testing, insulin-like growth factor-1 (IGF-1), IGF binding protein 3 (IGFBP-3), insulin, glucose, cholesterol, triglycerides, free fatty acids and nitric oxide levels. Body composition and IAT content were evaluated by dual-energy x-ray-absorptiometry and magnetic resonance imaging. An excess accumulation of IAT was defined as a value > 41 cm2. Differences between children with (V+) and without (V-) excess IAT were assessed by non-parametric tests and multivariate analysis.RESULTS Ten V+ (mean IAT, 82.5 cm2) and 15 V- (mean IAT, 26.8 cm2) were identified; they were similar for age (13.8 versus 14.8 years), body mass index (20.2 versus 19.5 kg/m2), male : female ratio (3/7 versus 8/7), months on highly active antiretroviral therapy (54.5 versus 55 months). V+ showed lower GH-AUC(0-120 min) (16.4 versus 31.6 microg x h/l; P = 0.002), lower IGF-1 concentrations (384 versus 515 ng/ml; P = 0.03) and higher insulin levels (17.8 versus 10.5 microIU/ml; P = 0.01) than V-. V+, as compared to V-, showed lower lean mass (total, P = 0.025; arms, P = 0.024; legs, P = 0.008) and higher fat mass (total, P = 0.0038; arms, P = 0.028; trunk, P < 0.0001). Lipid profile and glucose, IGFBP-3, nitric oxide and free fatty acids levels were similar in the two groups. GH-AUC(0-120 min) correlated negatively with IAT content and insulin levels. CONCLUSION: Impaired GH secretion is detectable in pubertal children with increased visceral adiposity and hyperinsulinemia. GH therapy should be considered in lipodystrophic HIV-infected children with excess IAT.  相似文献   
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