全文获取类型
收费全文 | 1115篇 |
免费 | 182篇 |
国内免费 | 19篇 |
专业分类
耳鼻咽喉 | 19篇 |
儿科学 | 50篇 |
妇产科学 | 16篇 |
基础医学 | 45篇 |
口腔科学 | 18篇 |
临床医学 | 173篇 |
内科学 | 258篇 |
皮肤病学 | 72篇 |
神经病学 | 80篇 |
特种医学 | 112篇 |
外科学 | 223篇 |
综合类 | 53篇 |
现状与发展 | 20篇 |
预防医学 | 59篇 |
眼科学 | 28篇 |
药学 | 20篇 |
中国医学 | 2篇 |
肿瘤学 | 68篇 |
出版年
2024年 | 8篇 |
2023年 | 43篇 |
2021年 | 22篇 |
2020年 | 24篇 |
2019年 | 13篇 |
2018年 | 59篇 |
2017年 | 52篇 |
2016年 | 42篇 |
2015年 | 47篇 |
2014年 | 46篇 |
2013年 | 65篇 |
2012年 | 30篇 |
2011年 | 37篇 |
2010年 | 54篇 |
2009年 | 73篇 |
2008年 | 46篇 |
2007年 | 41篇 |
2006年 | 47篇 |
2005年 | 34篇 |
2004年 | 40篇 |
2003年 | 29篇 |
2002年 | 27篇 |
2001年 | 32篇 |
2000年 | 17篇 |
1999年 | 21篇 |
1998年 | 29篇 |
1997年 | 33篇 |
1996年 | 46篇 |
1995年 | 29篇 |
1994年 | 17篇 |
1993年 | 21篇 |
1992年 | 7篇 |
1991年 | 9篇 |
1990年 | 11篇 |
1989年 | 12篇 |
1988年 | 16篇 |
1987年 | 14篇 |
1986年 | 11篇 |
1985年 | 12篇 |
1984年 | 5篇 |
1983年 | 7篇 |
1982年 | 9篇 |
1981年 | 5篇 |
1980年 | 6篇 |
1978年 | 12篇 |
1977年 | 10篇 |
1976年 | 7篇 |
1975年 | 5篇 |
1964年 | 5篇 |
1963年 | 4篇 |
排序方式: 共有1316条查询结果,搜索用时 189 毫秒
21.
Until recently, axillary node clearance had long been the standard of care in patients with axillary node-positive disease. One stop nucleic acid sampling (OSNA) has been used to guide intraoperative decision-making regarding suitability for axillary node clearance (ANC). The aim of this study is to evaluate the use of OSNA following neoadjuvant chemotherapy (NACT) and whether it can predict lymph node burden in ANC. A single center, prospective cohort study was performed on 297 patients having OSNA between 2016 and 2019. Patients were sub-classified according to node positivity at diagnosis and those treated with NACT and outcomes included copy number and lymph node harvest. Axillary complete pathological response was observed in 24/36 patients (67%) following NACT. 14/16 patients (87%) having axillary node clearance had axillary node disease limited to 4 nodes. OSNA copy numbers were significantly higher in patients showing disease progression following NACT. Overall, 73% of patients with lymph node positivity at diagnosis could be successfully treated with a combination of NACT and lymph node excision of four nodes. De-escalating axillary surgical treatment to resection of four nodes following NACT may be effective in balancing oncological resection and limiting treatment morbidity. ONSA can correctly identify patients experiencing disease progression who would benefit from traditional three-level ANC. 相似文献
22.
Al-Bahry SN Al-Mashani BM Al-Ansari AS Elshafie AE Mahmoud IY 《Asian Pacific journal of tropical medicine》2013,6(9):718-722
ObjectiveTo screen for Escherichia coli (E. coli) resistant to tetracycline, followed by identification of tet efflux genes by polymerase chain reaction (PCR). In addition, detection of tetracycline residues in chicken livers and kidneys were conducted using high performance liquid chromatography-tandem quadrupole mass spectrometry (HPLC-MS-MS).MethodsStrains of E. coli were isolated from samples of chicken colon and screened for tetracycline resistance. Tetracycline genes conferring resistance (Tcr) were detected by polymerase chain reaction (PCR). Most of the isolates were resistant to tetracycline (97.9%).ResultsPCR analysis indicated that Tcr E. coli R-plasmids contained tet(A), tet(B) and a combination of both efflux genes. None of the isolates contained other efflux tet genes tet (C, D, E and Y). High performance liquid chromatography-tandem quadrupole mass spectrometry (HPLC-MS-MS), a sensitive technique, was used to detect residues of chlortetracycline (CTC), oxytetracycline (OTC), doxycycline (DC) in chicken livers and kidneys. The samples containing tetracycline residues were at 0.13-0.65 pg/μL levels.ConclusionsTetracycline and other antibiotics are commonly used in the poultry and meat production industry for prevention of microbial infections. Multiple antibiotic resistant bacteria in Oman have increased to alarming levels, threatening public health, domestic and may have adverse effect on environment. 相似文献
23.
Wearable monitors for patients following discharge from an intensive care unit: practical lessons learnt from an observational study 下载免费PDF全文
24.
25.
26.
ECG‐gated pulmonary artery CTA for evaluation of right ventricular function in patients with acute pulmonary embolism 下载免费PDF全文
27.
NADPH oxidase is an enzyme in the plasma membrane of the neutrophil that catalyzes the production of O2-, a species central to the oxygen- dependent killing mechanisms of this cell. The oxidase is dormant in resting cells and is activated upon the addition of a stimulus. Neutrophils of patients with chronic granulomatous disease (CGD) manifest no oxidase activity when stimulated. The possible role of protein phosphorylation in the activation of NADPH oxidase was examined in normal and CGD neutrophils by measuring the incorporation of 32Pi into proteins as determined by gel electrophoresis followed by autoradiography. Resting neutrophils from normal subjects exhibit at least 40 distinct phosphoprotein bands. The level of phosphorylation of these bands was examined after the addition of phorbol myristate acetate (PMA), opsonized zymosan, digitonin, N-formyl-methionyl- phenylalanine (FMLP), or NaF. PMA and opsonized zymosan increased the phosphorylation of a set of 6 protein bands. Digitonin and FMLP consistently caused the phosphorylation of 4 of these protein bands, while NaF failed to induce increased phosphorylation of any protein band. All activators tested caused the dephosphorylation of one specific protein band. The time course of phosphorylation (dephosphorylation) was examined using PMA as the activating agent. Increased phosphorylation of one protein band was evident by 12 sec after the addition of PMA. The most slowly phosphorylated protein band did not slow evidence of change until 5 min after the addition of PMA. Three of the phosphoproteins examined were phosphorylated either earlier than or concomitant with the activation of NADPH oxidase. CGD neutrophils were compared with normal cells for their ability to phosphorylate proteins in response to PMA. The phosphoprotein banding patterns of CGD neutrophils were identical with those of normal neutrophils in both the resting and activated states. The evidence presented shows that the phosphorylation of proteins is a prominent feature of neutrophil metabolism. The striking similarity of phosphorylation changes induced by the various activators tested suggests that protein phosphorylation may play a role in some aspects of neutrophil activation. Evidence was not obtained, however, regarding a link between protein phosphorylation and activation of NADPH oxidase. 相似文献
28.
The role of defective fibrinolysis caused by elevated activity of plasminogen activator inhibitor-1 (PAI-1) in promoting fibrin deposition in vivo has not been well established. The present study compared the efficacy of thrombin or ancrod, a venom-derived enzyme that clots fibrinogen, to induce fibrin formation in rabbits with elevated PAI-1 levels. One set of male New Zealand rabbits received intravenous endotoxin to increase endogenous PAI-1 activity followed by a 1-hour infusion of ancrod or thrombin; another set of normal rabbits received intravenous human recombinant PAI-1 (rPAI-1) during an infusion of ancrod or thrombin. Thirty minutes after the end of the infusion, renal fibrin deposition was assessed by histopathology. Animals receiving endotoxin, rPAI-1, ancrod, or thrombin alone did not develop renal thrombi. All endotoxin-treated rabbits developed fibrin deposition when infused with ancrod (n = 4) or thrombin (n = 6). Fibrin deposition occurred in 7 of 7 rabbits receiving both rPAI-1 and ancrod and in only 1 of 6 receiving rPAI-1 and thrombin (P < .01). In vitro, thrombin but not ancrod was inactivated by normal rabbit plasma and by purified antithrombin III or thrombomodulin. The data indicate that elevated levels of PAI-1 promote fibrin deposition in rabbits infused with ancrod but not with thrombin. In endotoxin-treated rabbits, fibrin deposition that occurs with thrombin infusion may be caused by decreased inhibition of procoagulant activity and not increased PAI-1 activity. 相似文献
29.
Özdemir Hüseyin Mahmutyazıcıoğlu Kamran Ünal Aysun Savranlar Ahmet Atasoy H. Tuğrul Sümer Murat Gündoğdu Sadi 《The International journal of angiology》2003,12(4):266-269
Unilateral congenital agenesis of the internal carotid artery (ICA) is a very rare vascular anomaly. Rarely, congenital Horners syndrome has been associated with agenesis of the ICA. This article describes a rare case of congenital Horners syndrome in a patient with ICA agenesis and very unusual aortic arch anomaly.
This study was done at Zonguldak Karaelmas University, Faculty of Medicine, No financial support was required for this study. 相似文献
30.
Tricuspid annulus motion and mitral annulus motion: Anatomical intimacy causing a good correlation? 下载免费PDF全文