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91.
We have recently described a novel phenotype in a group of subjects with type 1 diabetes that is manifested by glucose >11.1 mmol/l 120 min after an oral glucose load, but with normal fasting glucose levels. We now describe the metabolic characteristics of these subjects by comparing parameters of islet hormone secretion and glucose disposal in these subjects to age-matched nondiabetic control subjects. The patients with type 1 diabetes had fasting glucose, insulin, and glucagon values similar to those of control subjects. Additionally, the insulin secretory response to intravenous arginine at euglycemia was similar in the control and diabetic groups (264 +/- 33.5 and 193 +/- 61.3 pmol/l; P = 0.3). However, marked differences in beta-cell function were found in response to hyperglycemia. Specifically, the first-phase insulin response was lower in diabetic subjects (329.1 +/- 39.6 vs. 91.3 +/- 34.1 pmol/l; P < 0.001), as was the slope of glucose potentiation of the insulin response to arginine (102 +/- 18.7 vs. 30.2 +/- 6.1 pmol/l per mmol/l; P = 0.005) and the maximum insulin response to arginine (2,524 +/- 413 vs. 629 +/- 159 pmol/l; P = 0.001). Although plasma levels of glucagon-like peptide (GLP)-1 and gastric inhibitory peptide (GIP) did not differ between control and diabetic subjects, the incretin effect was lower in the diabetic patients (70.3 +/- 5.4 vs. 52.1 +/- 5.9%; P = 0.03). Finally, there was a lack of suppression of glucagon in the patients after both oral and intravenous glucose administration, which may have contributed to their postprandial hyperglycemia. Glucose effectiveness did not differ between patients and control subjects, nor did insulin sensitivity, although there was a tendency for the patients to be insulin resistant (9.18 +/- 1.59 vs. 5.22 +/- 1.17 pmol.(-1).min(-1); P = 0.08). These data characterize a novel group of subjects with type 1 diabetes manifested solely by hyperglycemia following an oral glucose load in whom islet function is normal at euglycemia, but who have marked defects in both alpha- and beta-cell secretion at hyperglycemia. This pattern of abnormalities may be characteristic of islet dysfunction early in the development of type 1 diabetes.  相似文献   
92.
BACKGROUND: Despite its common acceptance in clinical practice, the effective benefits of normothermic systemic perfusion during coronary artery bypass operations are far from established. METHODS: A total of 113 patients undergoing primary isolated coronary artery bypass were randomly assigned to normothermic (37 degrees C) or hypothermic (26 degrees C) systemic perfusion. The clinical course of the patients was prospectively recorded, and several inflammatory and fibrinolytic markers (C-reactive protein, fibrinogen, interleukin 6, plasminogen activator inhibitor 1, prothrombin time, activated partial thromboplastin time, platelets, and white blood cell counts) were determined before surgical intervention; 24, 48, and 72 hours thereafter; and at hospital discharge. RESULTS: Postoperatively, 2 in-hospital deaths occurred in the normothermic series and none in the hypothermic series. Four patients had a myocardial infarction, 1 had respiratory insufficiency, 1 had to be reoperated on for graft malfunction, and none had renal insufficiency in the hypothermic group versus 1 patient with each of these complications in the normothermic series. Mean blood loss in the first 24 hours was 766 +/- 223 mL in the normothermic group and 740 +/- 220 mL in the hypothermic group. None of these differences was statistically significant. Similarly, no significant difference in the postoperative level of any of the measured variables at any time point was evident between the patients in the normothermic and hypothermic groups. CONCLUSION: Normothermic systemic perfusion does not influence the clinical course or the extent of inflammatory and hemostatic activation in patients undergoing primary isolated coronary artery bypass.  相似文献   
93.
Purpose For many years, the status of the axillary lymph nodes has been determined by an axillary lymphadenectomy. However, a sentinel lymph node biopsy has been shown to effectively replace the need for an axillary lymphadenectomy in order to determine the axillary staging. This study presents the preliminary results regarding the efficacy of fine-needle aspiration cytology (FNAC) to identify metastatic axillary lymph nodes in the pre-operative phase. Methods One hundred lymph nodes from 100 patients with histologically and cytologically confirmed breast cancer (cT1–2 cN0) underwent echo-guided FNAC. The diagnostic accuracy (sensitivity, specificity, positive predictive value [PPV], negative predictive value [NPV]) for the axillary metastases was evaluated based on the histological findings of either a sentinel lymph node biopsy or an axillary lymphadenectomy as a reference standard. Results It was possible to avoid a sentinel lymph node biopsy in 30% of the cases; the sensitivity was 68%, specificity 100%, PPV 100%, and NPV 65%. Echo-guided FNAC of the axillary lymph nodes should thus be included among the regular diagnostic procedures of presurgical staging. Conclusion This simple, inexpensive, and minimally invasive technique makes it possible to avoid the additional cost of a sentinel lymph node biopsy while also sparing the patient the stress of undergoing a second surgery.  相似文献   
94.
Background Obesity is the most important risk factor for obstructive sleep apnea. It is estimated that 70% of sleep apnea patients are obese. In the morbidly obese, the prevalence may reach 80% in men and 50% in women. The aim of this study was to determine the prevalence and severity of sleep apnea in a group of morbidly obese patients, leading to bariatric surgery. Methods In a cross-sectional study developed in Bahia, northeastern Brazil. 108 patients (78 women and 30 men) from the Obesity Treatment and Surgery Center - “Núcleo de Tratamento e Cirurgia da Obesidade” underwent standard polysomnography. Patients with an apnea-hypopnea index (AHI) ≥ 5 events/hour were considered apneic. Results Mean ± SD for age and BMI were 37.1 ± 10.2 years and 45.2 ± 5.4 kg/m2, respectively. The calculated AHI ranged widely from 2.5 to 128.9 events/hour. Sleep apnea was detected in 93.6% of the sample, wherein 35.2% had mild, 30.6% moderate and 27.8% severe apnea. Oxyhemoglobin desaturation was directly related to the AHI and was more severe in men. Conclusion There was a high frequency of sleep apnea in this group of morbidly obese patients, for whom it was very important to request polysomnography, thus enabling therapeutic management and prognostication.  相似文献   
95.
Mandibulofacial dysostosis (Treacher Collins Syndrome) is an autosomal dominant genetic disorder that probably derives from inhibition of the facial structures from the first and second branchial arches. The facial pattern of the syndrome is a convex facial profile with a prominent nose above a retruded chin. The eyes are deformed by antimongoloid slant of the palpebral fissures and facial bones are hypoplastic. The alterations are caused by mutation in gene 5q32-33.1, which encodes the nucleolar phosphoprotein treacle. Computed tomography images are able to demonstrate craniofacial bones, allowing the morphological analysis of these bones in individuals with complex deformities. The purpose of this paper is to present the results of a clinical and computed tomography investigation of two patients with Treacher Collins syndrome.  相似文献   
96.
BACKGROUND: Evidence from animal studies indicate a crucial role for CD25(bright+) regulatory T cells in transplantation tolerance. METHODS: To assess whether peripheral CD25(bright+) T cells control immune responses in immunosuppressed kidney transplant patients, we analyzed the suppressive capacities of these cells using mixed lymphocytes reactions. RESULTS: Allogeneic stimulation of patients peripheral blood mononuclear cells was associated with IL-2 production and T-cell proliferation. Depletion of CD25(bright+) T cells resulted in a 35% (median) higher IL-2 production and a 38% higher proliferative response against third party cells, showing that functional regulatory CD25(bright+) T cells were present (p = 0.03 and 0.02 respectively). In eight out of 11 patients, we also demonstrated regulation activity against donor-activated T cells (p = 0.03). These data were confirmed in coculture experiments with isolated CD25(-/dim) T cells plus CD25(bright+) T cells. At a 1:2 ratio, the CD25(bright+) T cells suppressed the proliferation of CD25(-/dim) donor- and third party-stimulated responder T cells. CONCLUSIONS: CD25(bright+) T cells with immune regulatory activities against anti-donor-responsive T cells are readily detectable in renal allograft recipients during treatment with full dosage immunosuppression. Whether CD25(bright+) T cells indeed play a role in graft acceptance after organ transplantation in patients remains to be elucidated.  相似文献   
97.
Bone marrow fat, an unique component of the bone marrow cavity increases with aging and menopause and is inversely related to bone mass. Sex steroids may be involved in the regulation of bone marrow fat, because men have higher bone marrow fat than women and clinical observations have suggested that the variation in bone marrow fat fraction is greater in premenopausal compared to postmenopausal women and men. We hypothesized that the menstrual cycle and/or estrogen affects the bone marrow fat fraction. First, we measured vertebral bone marrow fat fraction with Dixon Quantitative Chemical Shift MRI (QCSI) twice a week during 1 month in 10 regularly ovulating women. The vertebral bone marrow fat fraction increased 0.02 (95% CI, 0.00 to 0.03) during the follicular phase (p = 0.033), and showed a nonsignificant decrease of 0.02 (95% CI, –0.01 to 0.04) during the luteal phase (p = 0.091). To determine the effect of estrogen on bone marrow fat, we measured vertebral bone marrow fat fraction every week for 6 consecutive weeks in 6 postmenopausal women before, during, and after 2 weeks of oral 17‐β estradiol treatment (2 mg/day). Bone marrow fat fraction decreased by 0.05 (95% CI, 0.01 to 0.09) from 0.48 (95% CI, 0.42 to 0.53) to 0.43 (95% CI, 0.34 to 0.51) during 17‐β estradiol administration (p < 0.001) and increased again after cessation. During 17‐β estradiol administration the bone formation marker procollagen type I N propeptide (P1NP) increased (p = 0.034) and the bone resorption marker C‐terminal crosslinking telopeptides of collagen type I (CTx) decreased (p < 0.001). In conclusion, we described the variation in vertebral bone marrow fat fraction among ovulating premenopausal women. And among postmenopausal women, we demonstrated that 17‐β estradiol rapidly reduces the marrow fat fraction, suggesting that 17‐β estradiol regulates bone marrow fat independent of bone mass. © 2015 American Society for Bone and Mineral Research.  相似文献   
98.
Previously, we demonstrated in heart transplant patients that FOXP3, a gene required for the development and function of regulatory T cells, was highly expressed in the graft during an acute cellular rejection. In this study, we analyzed whether the FOXP3 gene expression in the peripheral blood also reflects anti-donor immune responses, and therefore may provide clues for non-invasive detection of non-responsiveness or acute rejection. We examined the FOXP3 expression patterns of peripheral blood mononuclear cells (PBMC; n=69) of 19 heart transplant patients during quiescence and rejection in comparison with those of endomyocardial biopsies (EMB; n=75) of 24 heart transplant patients. While the FOXP3 mRNA levels were abundantly expressed in rejecting EMB (ISHLT rejection grade>1R) compared with EMB without histological evidence of myocardial damage (ISHLT rejection grade 0R-1R; p=0.003), no association with rejection or non-responsiveness was found for the FOXP3 mRNA levels in the peripheral blood. Thus, in contrast to intragraft FOXP3 gene expression, the peripheral FOXP3 mRNA levels lack correlation with anti-donor immune responses in the graft, and, consequently, FOXP3 does not appear to be a potential candidate gene for non-invasive diagnosis of non-responsiveness or rejection.  相似文献   
99.
Lepidium meyenii ( Maca ) improved semen parameters in adult men   总被引:6,自引:0,他引:6  
Aim: The present study was designed to determine the effect of a 4-month oral treatment with tablets of Lepidium meyenii (Maca) on seminal analysis in nine adult normal men aged 24 - 44 years old. Methods: Nine men received tablets of Maca (1500 or 3000 mg/day) for 4 months. Seminal analysis was performed according to guidelines of the World Health Organization (WHO). Serum luteinizing hormone (LH), follicle stimulating hormone (FSH), prolactin (PRL), testosterone (T) and estradiol (E2) were measured before and after treatment. Results: Treatment with Maca resulted in increased seminal volume, sperm count per ejaculum, motile sperm count, and sperm motility. Serum hormone levels were not modified with Maca treamaent. Increase of sperm count was not related to dose of Maca. Conclusion: Maca improved sperm production and sperm motility by mechanisms not related to LH, FSH, PRL, T and E2.  相似文献   
100.
Abstract

This paper provides an overview of more than 22?years of research conducted in the central Javanese province of Yogyakarta, Indonesia, by teams of researchers associated with Gadjah Mada University and Harvard University, led by the authors of this essay. This work is placed in the context of the very limited literature on early psychosis and mental health services in Indonesia. It provides an overview of mental health services in Indonesia and of this team’s research trajectory, then addresses four key domains: the cultural phenomenology of early experiences of psychotic illness; patterns of onset, with a particular focus on extremely rapid onset psychoses; patterns of care-seeking for first episode illness; and mental health services and patterns of utilization. It then discusses the importance of rapid onset psychosis for research on early psychosis, and the question of whether collinearity of rapidity of onset and rapidity of care-seeking raises questions about the long-standing finding that a short duration of untreated psychosis leads to better outcomes. It concludes by discussing difficulties of prioritizing early intervention models in settings with very low mental health resources.  相似文献   
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