首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   326篇
  免费   8篇
耳鼻咽喉   1篇
儿科学   7篇
妇产科学   4篇
基础医学   69篇
口腔科学   1篇
临床医学   11篇
内科学   57篇
皮肤病学   13篇
神经病学   62篇
特种医学   5篇
外科学   37篇
预防医学   8篇
眼科学   1篇
药学   22篇
肿瘤学   36篇
  2023年   2篇
  2021年   2篇
  2020年   1篇
  2019年   3篇
  2018年   5篇
  2017年   4篇
  2016年   3篇
  2015年   5篇
  2014年   2篇
  2013年   8篇
  2012年   24篇
  2011年   27篇
  2010年   7篇
  2009年   6篇
  2008年   26篇
  2007年   28篇
  2006年   37篇
  2005年   38篇
  2004年   33篇
  2003年   26篇
  2002年   20篇
  2001年   1篇
  2000年   2篇
  1999年   4篇
  1998年   2篇
  1997年   2篇
  1996年   1篇
  1995年   1篇
  1990年   3篇
  1989年   2篇
  1988年   2篇
  1985年   1篇
  1984年   1篇
  1982年   2篇
  1977年   1篇
  1976年   1篇
  1974年   1篇
排序方式: 共有334条查询结果,搜索用时 0 毫秒
61.
We aimed to identify and compare cerebral activations in schizophrenia patients and controls during a working memory (WM) task at the same performance level for both a verbal and a spatial task. Whereas the performances of the patients (n=22) and controls (n=15) were similar, cerebral activations were significantly increased in the patients, particularly in the thalamus/basal ganglia for the two tasks and in regions of the prefrontal cortex and the cerebellum for the spatial task only. Our results suggest that stronger activations of deep brain structures in patients may be the result from a compensating mechanism for WM difficulties.  相似文献   
62.
Macrophagic myofasciitis (MMF) is a specific histopathologic lesion involved in the persistence for years of aluminum hydroxide [Al(OH)(3)] at the site of previous intramuscular (i.m.) injection. In order to study mechanisms involved persistence of MMF lesions, we set up an experimental model of MMF-lesion in Sprague-Dawley and Lewis rat, by i.m. injections of 10 microL of an Al(OH)(3)-adjuvanted vaccine. An evaluation carried out over a 12-month period disclosed significant shrinkage of MMF lesions with time. A radioisotopic study did not show significant aluminium uptake by Al(OH)(3)-loaded macrophages. A morphometric approach showed that Lewis rats with Th1-biased immunity had significantly smaller lesions than Sprague-Dawley rats with balanced Th1/Th2 immunity. Concluding, our results indicate that genetic determinatives of cytotoxic T-cell responses could interfere with the clearance process and condition the persistence of vaccine-induced MMF-lesions.  相似文献   
63.
BACKGROUND: Although we have shown in three out of five patients with Huntington's disease that motor and cognitive improvements 2 years after intracerebral fetal neural grafts are correlated with recovery of brain metabolic activity in grafted striatal areas and connected regions of the cerebral cortex, neural grafts are not known to have protective effects on the host brain per se. We undertook long-term follow-up of previously reported patients with the disease to ascertain the nature and extent of any secondary decline after grafting. METHODS: Five patients with Huntington's disease from our pilot study were assessed annually with the unified Huntington's disease rating scale, neuropsychological tests, and MRI, for up to 6 years after neural grafting. Resting cerebral activity was recorded at 2 and 6 years. FINDINGS: Clinical improvement plateaued after 2 years and then faded off variably 4-6 years after surgery. Dystonia deteriorated consistently, whereas chorea did not. Cognitive performance remained stable on non-timed tests, whereas progression of motor disability was shown by deterioration on timed tests. Hypometabolism also affected the brain heterogeneously, sparing the benefits in the frontal cortex and at the precise location of the grafts, but showing a progressive deterioration in other areas. Two patients who had no benefit from grafting at 2 years continued to decline in the same way as non-grafted patients. INTERPRETATION: Neuronal transplantation in Huntington's disease provides a period of several years of improvement and stability, but not a permanent cure for the disease. Improvement of the surgical procedure and in patient selection could improve the therapeutic value, but neuroprotective treatment seems to be unavoidable in the disease.  相似文献   
64.
Spontaneous dissections of the superior mesenteric artery are exceptional events because only 26 reports have been published. We present a new case, revealed with an acute abdominal syndrome. Computed tomographic angiography and arteriography allowed a rapid diagnosis and urgent surgical intervention. Progress in imagery makes diagnosis and follow-up examination easier. Surgery is indicated for acute symptomatic forms with suspicion of mesenteric ischemia. In the other cases, a simple follow-up examination may be appropriate.  相似文献   
65.
Extragonadal germ cell tumors most commonly arise in the midline of the retroperitoneum or the mediastinum. Primary tumors involving the skin are very rare. Only one case of malignant primary germ cell tumor located in the skin has been reported. We present the case of a 44-year-old white man with a primary subcutaneous mixed nonseminomatous germ cell tumor. This man had a long-lasting subcutaneous lump of the breast, which became painful. Surgery revealed 3 juxtaposed nodules. Microscopic examination showed a mixed germ cell tumor with a 90% immature teratoma component and a 10% embryonal carcinoma component. Testicular ultrasound and computed tomography of the chest, abdomen, pelvis, and brain were normal. Serum human chorionic gonadotrophin, beta-human chorionic gonadotrophin, alpha-fetoprotein, and lactate dehydrogenase were within normal ranges. A further surgical excision was performed. The patient is presently alive with no evidence of disease after a follow-up of 7 years. Review of the literature indicates that primary cutaneous extragonadal germ cell tumors usually occur as cutaneous or subcutaneous solitary nodules or as ulcerated lesions. They mainly consist of mature teratomas in children. Only 2 cases have been reported in adults.  相似文献   
66.
67.
A genetically mediated abnormal sensitivity to stress is thought to play a role in the onset, exacerbation and relapse of schizophrenia. In a double blind, placebo-controlled crossover study, peak increases in plasma ACTH (ΔACTH) and homovanillic-acid, a dopamine metabolite, (ΔHVA) following exposure to a metabolic stressor(2DG) were studied in unaffected siblings of patients with schizophrenia (n = 15), their patient relatives (n = 15) and healthy controls (n = 14). Siblings showed a stress response (both ΔACTH and ΔHVA) that was significantly greater compared to controls and significantly less pronounced compared to patients. The results suggest that the genetic risk for schizophrenia may be characterized by an enhanced sensitivity to stress.  相似文献   
68.
69.
In the present study we investigated the phosphorylation status of the 12 most important signaling cascades in glioblastomas. More than 60 tumor and control biopsies from tumor center and periphery (based on neuronavigation) were subjected to selective protein expression analysis using reverse-phase protein arrays (RPPA) incubated with antibodies against posttranslationally modified cancer pathway proteins. The ratio between phosphorylated (or modified) and non-phosphorylated protein was assessed. All samples were histopathologically validated and proteomic profiles correlated with clinical and survival data. By RPPA, we identified three distinct activation patterns within glioblastoma defined by the ratios of pCREB1/CREB1, NOTCH-ICD/NOTCH1, and pGSK3β/GSK3β, respectively. These subclasses demonstrated distinct overall survival patterns in a cohort of patients from a single-institution and in an analysis of publicly available data. In particular, a high pGSK3β/GSK3β-ratio was associated with a poor survival. Wnt-activation/GSK3β-inhibition in U373 and U251 cell lines halted glioma cell proliferation and migration. Gene expression analysis was used as an internal quality control of baseline proteomic data. The protein expression and phosphorylation had a higher resolution, resulting in a better class-subdivision than mRNA based stratification data. Patients with different proteomic profiles from multiple biopsies showed a worse overall survival. The CREB1-, NOTCH1-, GSK3β-phosphorylation status correlated with glioma grades. RPPA represent a fast and reliable tool to supplement morphological diagnosis with pathway-specific information in individual tumors. These data can be exploited for molecular stratification and possible combinatorial treatment planning. Further, our results may optimize current glioma grading algorithms.  相似文献   
70.
BACKGROUND: Chemotherapeutic agents have been reported to cause severe arrhythmias and sudden death in the first 24 hr after administration. In this prospective study, we determined the magnitude of acute arrhythmogenicity of those agents in children. PROCEDURE: Thirty-three patients with diverse malignancies (leukemia n = 16, Wilms tumor n = 3, brain tumor n = 3, lymphoma n = 3, others n = 8) were studied with Holter monitors 24 hr before, during, and in the first 24 hr following the first-dose therapy. RESULTS: Two patients experienced conduction disturbances (phases of 2nd degree sinuatrial and atrioventricular blocks) during a 4-hr period corresponding to a 30 mg/m(2) daunorubicin infusion. Eight patients experienced supraventricular extrasystole (SE), ventricular extrasystole (VE), and/or short salvos of supraventricular (SVT) and/or ventricular tachycardia (VT). Six had leukemia (therapy: daunorubicin + vincristine), one had a lymphoma (therapy: vincristine + cyclophosphamide), and the last one a brain tumor (therapy: carboplatin + procarbazine). Three patients with leukemia had pretreatment arrhythmias (1 VT, 2 SVT). One of them and the five other patients had arrhythmias during and after the first-dose therapy (2 VE, 2 SVT, 1 SVT + VE, 1 VE + SE + SVT). No patient had life-threatening arrhythmias and no prognostic value of those disturbances could be demonstrated. CONCLUSIONS: Conduction disturbances and arrhythmias are common in cancer children at the beginning of the therapy, but no acute or long-term adverse consequences are related to their appearance.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号