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   490篇
  免费   27篇
耳鼻咽喉   3篇
儿科学   5篇
基础医学   62篇
口腔科学   2篇
临床医学   36篇
内科学   94篇
皮肤病学   3篇
神经病学   185篇
特种医学   28篇
外科学   43篇
综合类   1篇
预防医学   1篇
眼科学   20篇
药学   10篇
肿瘤学   24篇
  2023年   3篇
  2022年   7篇
  2021年   9篇
  2020年   3篇
  2019年   1篇
  2018年   6篇
  2017年   7篇
  2016年   13篇
  2015年   13篇
  2014年   19篇
  2013年   21篇
  2012年   33篇
  2011年   34篇
  2010年   24篇
  2009年   18篇
  2008年   26篇
  2007年   53篇
  2006年   32篇
  2005年   36篇
  2004年   32篇
  2003年   22篇
  2002年   22篇
  2001年   1篇
  2000年   2篇
  1999年   3篇
  1998年   8篇
  1997年   4篇
  1996年   6篇
  1995年   3篇
  1994年   8篇
  1993年   4篇
  1992年   7篇
  1991年   5篇
  1990年   4篇
  1989年   2篇
  1988年   2篇
  1987年   2篇
  1986年   4篇
  1985年   4篇
  1984年   1篇
  1983年   1篇
  1981年   2篇
  1980年   2篇
  1979年   2篇
  1978年   1篇
  1977年   1篇
  1976年   1篇
  1957年   3篇
排序方式: 共有517条查询结果,搜索用时 31 毫秒
1.
2.
3.
The effect of the cholinergic blocker, scopolamine on the cerebral blood flow (CBF) response to vibrotactile stimulation of a fore paw was studied using high-resolution positron emission tomography and H215O in 5 pentobarbital-anesthetized cats. Before scopolamine injection, the CBF response to the stimulation was found in the contralateral somatosensory cortex (mean ratio (contralateral/ipsilateral) control: stimulated1.02 ± 0.02: 1.17 ± 0.05; P < 0.01). After intravenous injection of scopolamine (0.35 mg/kg), the CBF response was abolished. However, the cerebral metabolic rate of glucose (CMRGlu) response to the same stimulation was unchanged after scopolamine injection in the same cats. We concluded that scopolamine abolishes the CBF response but not neuronal response to stimulation. We suggest that cholinergic mechanisms may play an important role for mediating CBF coupling to neuronal activity during physiological stimulation.  相似文献   
4.
5.
INTRODUCTION: Orotate phosphoribosyl transferase (OPRT), dihydropyrimidine dehydrogenase (DPD), and thymidylate synthase (TS) are initial key enzymes in the 5-fluorouracil (5-FU) metabolic pathway. The expression levels and activities of these three enzymes play important roles in the response of cancer patients to 5-FU-based chemotherapy. PURPOSE: The purpose of this study was to investigate the relationship between the activities of 5-FU metabolic enzymes and clinicopathologic factors in colorectal cancer. METHODS: We measured the activities of OPRT, DPD, and TS in colorectal cancer tissues. We also investigated the correlations between the activities of these three enzymes and clinicopathologic factors (histological type, depth of tumor invasion, extent of lymph node metastasis, Dukes' stage, lymphatic invasion, and vascular invasion). We examined 100 patients with surgically resected colorectal cancer. RESULTS: Poorly differentiated adenocarcinoma showed significantly higher DPD activities than did moderately differentiated or well-differentiated adenocarcinoma. In patients with lymph-node metastasis, OPRT activity was significantly lower than in patients without lymph-node metastasis. No significant relation was found between TS activity and histological type, depth of tumor invasion, extent of lymph node metastasis, Dukes' stage, lymphatic invasion, or vascular invasion. CONCLUSION: The response to 5-FU may be poor in patients with lymph-node metastasis, because of low OPRT activity, and in patients with poorly differentiated adenocarcinoma, because of high DPD activity.  相似文献   
6.
7.
A postmarketing surveillance study is ongoing to evaluate nivolumab treatment for Japanese patients with malignant melanoma and accumulate data on all adverse events (AE) and efficacy. In this interim analysis, we evaluated data from approximately 100 Japanese medical institutions obtained from the nivolumab approval date in Japan (4 July 2014) through 3 July 2016. Patients were monitored during the first 12 months of treatment. Nivolumab was administrated by i.v. infusion (2 mg/kg every 3 weeks). A total of 680 and 610 patients were evaluated for safety and efficacy, respectively. The incidences of adverse drug reactions (ADR) and grade 3 or higher ADR were 53.53% and 12.35%, respectively. Predominant ADR included hypothyroidism (11.32%) and abnormal enzyme activity, such as increase of aspartate aminotransferase (7.79%), alanine aminotransferase (6.76%), alkaline phosphatase (6.18%) and γ‐glutamyltransferase (5.44%). Grade 3 or higher ADR of special interest with an incidence of 1% or higher were hepatic function disorder (2.50%), colitis/diarrhea (2.06%) and infusion reaction (1.32%). No cases of encephalitis or venous thromboembolism, other AE of special interest, were observed. The estimated median overall survival was 379 days (95% confidence interval [CI], 290–not reached [NR]) in the overall population, NR (95% CI, 305–NR) for cutaneous melanoma and 340 days (95% CI, 275–NR) for mucosal melanoma. The improvement rate based on the antitumor response at the last evaluation was 22.2% (131/590 patients). No new safety concerns were raised, and serious ADR of special interest were infrequent. Nivolumab showed equivalent efficacy in patients with mucosal melanoma and those with cutaneous melanoma.  相似文献   
8.
A patient who developed myasthenia gravis (MG) 25 months after allogeneic bone marrow transplant was immunologically analyzed. OX40+CD4+ T cells in the peripheral blood prominently increased one month before the onset of MG. CD4/CD8 ratios, usually abnormally inverted in patients with chronic graft-vs.-host disease (cGVHD), showed pseudonormalization during the course of MG. We succeeded in uneventful rapid tapering of prednisolone (PSL) using mycophenolate mofetil (MMF). Monitoring of OX40+CD4+ T cells supported the tapering of PSL and MMF as a marker of cGVHD activity. This case suggested the utility of MMF and monitoring of OX40+CD4+ T cells in the management of cGVHD-associated autoimmune diseases.  相似文献   
9.
This multicenter prospective study was conducted to assess high-sensitivity troponin T (hs-TnT) and other biomarkers to decide and predict culprit lesions indicated for emergency percutaneous coronary intervention (PCI) in patients with suspicious acute coronary syndrome (ACS). We have reported Hs-TnT is the most sensitive biomarker for earlier diagnosis and decision making in patients with suspected ACS. In this study, we had conducted subanalysis investigating the usefulness for prediction of ACS culprit lesion. The patients with suspicious ACS and initially negative whole-blood rapid troponin T test, who underwent coronary angiogram (CAG), were enrolled (n = 74). Hs-TnT, quantitative assay for conventional troponin T (c-TnT), creatine kinase MB isozyme (CK-MB), and heart-type fatty acid-binding protein (H-FABP) were simultaneously measured. ACS culprit lesion was described as total occlusion, subtotal occlusion, and/or angiographical unstable lesion such as thrombosis, ulceration or irregularity. The CAG revealed that 49 cases had ACS lesions to be indicated for emergency PCI. The areas under the ROC curves and ROC-optimized cut-off of hs-TnT, c-TnT, CK-MB, and H-FABP were 0.75, 0.67, 0.68, and 0.75, respectively, and 18, 11, 2.0, and 4.6 ng/ml, respectively. In patients with total occlusion and 90–99 % of diameter stenosis (TIMI 2 or 3), hs-TnT could predict emergency PCI with significantly higher sensitivity compared with H-FABP (hs-TnT >14 ng/ml; 71 %, and H-FABP >6.2 ng/dl; 51 %, p = 0.021) and other biomarkers. Meanwhile, H-FABP displayed significant correlations with number of diseased vessels and presence of thrombotic lesion. The present study first revealed different characteristics of correlation between the angiographic culprit lesions and each cardiac biomarker. For prediction of ACS lesions requiring emergency PCI, hs-TnT had the highest sensitivity with satisfied analytical precision.  相似文献   
10.
Contrast‐induced nephropathy (CIN) is considered to result from intrarenal vasoconstriction, and occurs more frequently in impaired than in normal kidneys. It was hypothesized that iodinated contrast media would markedly change renal blood flow and vascular resistance in functionally impaired kidneys. Thirty‐six patients were enrolled (32 men; mean age, 75.3 ± 7.6 years) undergoing diagnostic coronary angiography and were divided into two groups based on the presence of chronic kidney disease (CKD), defined as an estimated glomerular filtration rate (eGFR) of < 60 mL/min per 1.73 m2 (CKD and non‐CKD groups, n = 18 in both). Average peak velocity (APV) and renal artery resistance index (RI) were measured by Doppler flow wire before and after administration of the iodinated contrast media. The APV and the RI were positively and inversely correlated with the eGFR at baseline, respectively (APV, R = 0.545, P = 0.001; RI, R = ?0.627, P < 0.001). Mean RI was significantly higher (P = 0.015) and APV was significantly lower (P = 0.026) in the CKD than in the non‐CKD group. Both APV (P < 0.001) and RI (P = 0.002) were significantly changed following contrast media administration in the non‐CKD group, but not in the CKD group (APV, P = 0.258; RI, P = 0.707). Although renal arterial resistance was higher in patients with CKD, it was not affected by contrast media administration, suggesting that patients with CKD could have an attenuated response to contrast media.  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