全文获取类型
收费全文 | 445篇 |
免费 | 53篇 |
国内免费 | 8篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 18篇 |
妇产科学 | 4篇 |
基础医学 | 72篇 |
口腔科学 | 2篇 |
临床医学 | 41篇 |
内科学 | 83篇 |
皮肤病学 | 4篇 |
神经病学 | 55篇 |
特种医学 | 58篇 |
外科学 | 27篇 |
综合类 | 9篇 |
预防医学 | 77篇 |
眼科学 | 7篇 |
药学 | 26篇 |
中国医学 | 2篇 |
肿瘤学 | 20篇 |
出版年
2023年 | 2篇 |
2021年 | 5篇 |
2020年 | 5篇 |
2019年 | 5篇 |
2018年 | 8篇 |
2017年 | 5篇 |
2016年 | 7篇 |
2015年 | 10篇 |
2014年 | 9篇 |
2013年 | 14篇 |
2012年 | 17篇 |
2011年 | 5篇 |
2010年 | 18篇 |
2009年 | 16篇 |
2008年 | 19篇 |
2007年 | 21篇 |
2006年 | 23篇 |
2005年 | 18篇 |
2004年 | 15篇 |
2003年 | 12篇 |
2002年 | 12篇 |
2001年 | 15篇 |
2000年 | 14篇 |
1999年 | 14篇 |
1998年 | 18篇 |
1997年 | 20篇 |
1996年 | 12篇 |
1995年 | 12篇 |
1994年 | 18篇 |
1993年 | 17篇 |
1992年 | 14篇 |
1991年 | 11篇 |
1990年 | 9篇 |
1989年 | 5篇 |
1988年 | 9篇 |
1987年 | 11篇 |
1986年 | 9篇 |
1985年 | 9篇 |
1984年 | 2篇 |
1983年 | 3篇 |
1982年 | 2篇 |
1981年 | 6篇 |
1980年 | 9篇 |
1978年 | 3篇 |
1977年 | 2篇 |
1976年 | 2篇 |
1975年 | 4篇 |
1974年 | 4篇 |
1973年 | 1篇 |
1971年 | 4篇 |
排序方式: 共有506条查询结果,搜索用时 15 毫秒
51.
52.
PO Ajiboye OA Abiodun MF Tunde-Ayinmode OIN Buhari EO Sanya KW Wahab 《African health sciences》2013,13(3):624-631
Back ground
Stroke produces a wide range of mental and emotional disorders. Neuropsychiatric complications associated with stroke may have negative effects on the social functioning, overall quality of life and the recovery of motor functioning of stroke survivors.Objective
To determine the prevalence and nature of psychiatric morbidity among stroke patients attending neurology outpatient clinic of the University of Ilorin Teaching Hospital (UITH), Ilorin-Nigeria.Methods
All patients with stroke aged 18 years and above at an outpatient neurology clinic in Ilorin, Nigeria were assessed for mental and emotional disorders using the Schedule for Clinical Assessment in Neuropsychiatry (SCAN) over one year (March 2009 to February 2010).Results
Overall prevalence of psychiatric morbidity was 36.0% (30/83) among 83 patients who constituted the study population. Specific diagnoses recorded were depression (19.2%), generalised anxiety disorder (9.6%), harmful alcohol use (2.4%); dementia, somatoform disorder, phobia and delusional disorder each had a prevalence of 1.2%. Clinical and sociodemographic variables were not significantly associated with psychiatric morbidity.Conclusion
Psychiatric disorders are often associated with stroke. Identifying and treating stroke patients with these psychiatric co-morbidities could thus help to improve the overall quality of life of these patients. 相似文献53.
Hale Z Toklu Judy Muller-Delp Zhihui Yang ?ehkar Oktay Yasemin Sakarya Kevin Strang Payal Ghosh Michael D Delp Philip J Scarpace Kevin KW Wang Nihal Tümer 《Journal of cerebral blood flow and metabolism》2015,35(12):1950-1956
Overpressure blast-wave induced brain injury (OBI) leads to progressive pathophysiologic changes resulting in a reduction in brain blood flow, blood brain barrier breakdown, edema, and cerebral ischemia. The aim of this study was to evaluate cerebral vascular function after single and repeated OBI. Male Sprague-Dawley rats were divided into three groups: Control (Naive), single OBI (30 psi peak pressure, 1 to 2 msec duration), and repeated (days 1, 4, and 7) OBI (r-OBI). Rats were killed 24 hours after injury and the basilar artery was isolated, cannulated, and pressurized (90 cm H2O). Vascular responses to potassium chloride (KCl) (30 to 100 mmol/L), endothelin-1 (10−12 to 10−7 mol/L), acetylcholine (ACh) (10−10 to 10−4 mol/L) and diethylamine-NONO-ate (DEA-NONO-ate) (10−10 to 10−4 mol/L) were evaluated. The OBI resulted in an increase in the contractile responses to endothelin and a decrease in the relaxant responses to ACh in both single and r-OBI groups. However, impaired DEA-NONO-ate-induced vasodilation and increased wall thickness to lumen ratio were observed only in the r-OBI group. The endothelin-1 type A (ETA) receptor and endothelial nitric oxide synthase (eNOS) immunoreactivity were significantly enhanced by OBI. These findings indicate that both single and r-OBI impairs cerebral vascular endothelium-dependent dilation, potentially a consequence of endothelial dysfunction and/or vascular remodelling in basilar arteries after OBI. 相似文献
54.
Generation of a self-tolerant but antigen-responsive T cell repertoire occurs in the thymus. Although glucocorticoids are usually considered immunosuppressive, there is also evidence that they play a positive role in thymocyte selection. To address the question of how endogenous glucocorticoids might influence the adaptive immune response, we generated GRlck-Cre mice, in which the glucocorticoid receptor gene (GR) is deleted in thymocytes prior to selection. These mice were immunocompromised, with reduced polyclonal T cell proliferative responses to alloantigen, defined peptide antigens, and viral infection. This was not due to an intrinsic proliferation defect, because GR-deficient T cells responded normally when the TCR was cross-linked with antibodies or when the T cell repertoire was "fixed" with αβ TCR transgenes. Varying the affinity of self ligands in αβ TCR transgenic mice showed that affinities that would normally lead to thymocyte-positive selection caused negative selection, and alterations in the TCR repertoire of polyclonal T cells were confirmed by analysis of TCR Vβ CDR3 regions. Thus, endogenous glucocorticoids are required for a robust adaptive immune response because of their promotion of the selection of T cells that have sufficient affinity for self, and the absence of thymocyte glucocorticoid signaling results in an immunocompromised state. 相似文献
55.
Lei Ye Husnain Kh Haider Shujia Jiang Rusan Tan In-Chin Song Ruowen Ge Peter K Law Eugene KW Sim 《老年心脏病学杂志》2006,3(3):152-160
Introduction Extensive cell death and an associated myocardial dys- function are the common features of chronic heart disease. Given the inadequate ability of the human heart to regenerate, a more recent approach to counter the remodel- ing process is to compensate for the loss of functioning cardiomyocyte number through stem cell transplantation with angiomyogenic potential.1,2 The novel approach of heart cell therapy is to repopulate the scar tissue with myogenic cells that may be functional… 相似文献
56.
Retinoic acid inhibition of ex vivo human immunodeficiency virus-associated apoptosis of peripheral blood cells. 总被引:5,自引:0,他引:5 下载免费PDF全文
Y Yang J Bailey M S Vacchio R Yarchoan J D Ashwell 《Proceedings of the National Academy of Sciences of the United States of America》1995,92(7):3051-3055
T cells from human immunodeficiency virus (HIV)-infected individuals undergo spontaneous and activation-induced ex vivo apoptosis. Here we report that peripheral blood mononuclear cells (PBMCs) obtained from six HIV-infected individuals exhibited reduced ex vivo DNA fragmentation and cell death after ingestion of all-trans-retinoic acid (tRA). These effects were attenuated with continued daily RA administration, which correlated with a > 5-fold decrease in serum peak RA concentrations. Incubation of PBMCs from HIV+ individuals with tRA in vitro resulted in decreased DNA fragmentation in a subset of patients, especially those having < 500 CD4+ T cells per mm3. tRA also inhibited apoptosis of preactivated normal PBMCs induced to die by restimulation, which raises the possibility of a common mechanism between activation-induced apoptosis of activated normal PBMCs and apoptosis associated with HIV infection. Whether HIV-associated apoptosis of PBMCs, and its prevention by RA, has an impact on T-cell survival or the course of disease in patients infected with HIV will require further evaluation. 相似文献
57.
58.
Philip Bao Douglas Potter David P Eisenberg Diana Lenzner Herbert J Zeh Kenneth KW Lee III Steven J Hughes Michael K Sanders Jennifer L Young A James Moser 《HPB : the official journal of the International Hepato Pancreato Biliary Association》2009,11(7):606-611
Background:
The surgeon''s contribution to patients with localized pancreatic adenocarcinoma (PAC) is a margin negative (R0) resection. We hypothesized that a prediction rule based on pre-operative imaging would maximize the R0 resection rate while reducing non-therapeutic intervention.Methods:
The prediction rule was developed using computed tomography (CT) and endoscopic ultrasound (EUS) data from 65 patients with biopsy-proven PAC who underwent attempted resection. The rule classified patients as low or high risk for non-R0 outcome and was validated in 78 subsequent patients.Results:
Model variables were: any evidence of vascular involvement on CT; EUS stage and EUS size dichotomized at 2.6 cm. In the validation cohort, 77% underwent resection and 58% achieved R0 status. If only patients in the low-risk group underwent surgery, the prediction rule would have increased the resection rate to 92% and the R0 rate to 73%. The R0 rate was 40% higher in low-risk compared with high-risk patients (P < 0.001). High risk was associated with a 67% rate of non-curative surgery (unresectable disease and metastases).Conclusion:
The prediction rule identified patients most likely to benefit from resection for PAC using pre-operative CT and EUS findings. Model predictions would have increased the R0 rate and reduced non-therapeutic interventions. 相似文献59.
Differential induction of apoptosis in undifferentiated and differentiated HL-60 cells by DNA topoisomerase I and II inhibitors 总被引:7,自引:0,他引:7
The effects of monocytic/macrophage and granulocytic differentiation induced by phorbol myristate acetate (TPA) and all-trans retinoic acid, respectively, were tested on the induction of apoptosis in human promyelocytic leukemia HL-60 cells treated with topoisomerase I and II inhibitors. Using a filter-binding assay, we observed a strong inhibition of DNA fragmentation induced by 3- and 24-hour continuous exposure to camptothecin, VP-16, VM-26, and m-AMSA in TPA- differentiated cells. The inhibition of the typical internucleosomal DNA fragmentation was confirmed by agarose gel electrophoresis. By contrast, drug-induced DNA fragmentation was not inhibited in retinoic acid-differentiated cells, and apoptosis occurred in these cells after 4 to 5 days in the absence of drug treatment. The TPA inhibitory effect was maximal after 24 hours of treatment and was correlated with differentiation, because phorbol dibutyrate ester was active, whereas 4- alpha-TPA, a nontumor promoter that does not induce differentiation, was not active. Using alkaline elution, we observed that TPA and retinoic acid differentiation were associated with changes in topoisomerase-mediated DNA breaks that were not correlated with their differential effects on drug-induced DNA fragmentation. Moreover, TPA also inhibited DNA fragmentation induced by vinblastine, cycloheximide, calphostin C, and x-rays. Using a cell-free system, we observed that DNA fragmentation was not inhibited in nuclei from TPA-differentiated cells. Rather, inhibition of apoptosis seemed to take place in the cytoplasm. We conclude that phenotypic changes associated with TPA- induced differentiation include inactivation of a cytoplasmic activity that can induce DNA fragmentation associated with apoptosis. 相似文献
60.