全文获取类型
收费全文 | 3305篇 |
免费 | 152篇 |
国内免费 | 9篇 |
专业分类
耳鼻咽喉 | 21篇 |
儿科学 | 100篇 |
妇产科学 | 48篇 |
基础医学 | 386篇 |
口腔科学 | 86篇 |
临床医学 | 210篇 |
内科学 | 763篇 |
皮肤病学 | 44篇 |
神经病学 | 243篇 |
特种医学 | 235篇 |
外科学 | 391篇 |
综合类 | 84篇 |
一般理论 | 1篇 |
预防医学 | 173篇 |
眼科学 | 136篇 |
药学 | 333篇 |
中国医学 | 15篇 |
肿瘤学 | 197篇 |
出版年
2023年 | 16篇 |
2022年 | 58篇 |
2021年 | 106篇 |
2020年 | 62篇 |
2019年 | 87篇 |
2018年 | 98篇 |
2017年 | 70篇 |
2016年 | 82篇 |
2015年 | 78篇 |
2014年 | 145篇 |
2013年 | 152篇 |
2012年 | 269篇 |
2011年 | 269篇 |
2010年 | 167篇 |
2009年 | 124篇 |
2008年 | 189篇 |
2007年 | 201篇 |
2006年 | 151篇 |
2005年 | 152篇 |
2004年 | 151篇 |
2003年 | 120篇 |
2002年 | 120篇 |
2001年 | 74篇 |
2000年 | 60篇 |
1999年 | 52篇 |
1998年 | 37篇 |
1997年 | 17篇 |
1996年 | 24篇 |
1995年 | 11篇 |
1994年 | 14篇 |
1993年 | 12篇 |
1992年 | 19篇 |
1991年 | 31篇 |
1990年 | 21篇 |
1989年 | 21篇 |
1988年 | 22篇 |
1987年 | 21篇 |
1986年 | 16篇 |
1985年 | 19篇 |
1984年 | 11篇 |
1983年 | 10篇 |
1982年 | 5篇 |
1979年 | 17篇 |
1977年 | 10篇 |
1976年 | 10篇 |
1975年 | 13篇 |
1974年 | 8篇 |
1972年 | 7篇 |
1971年 | 5篇 |
1968年 | 6篇 |
排序方式: 共有3466条查询结果,搜索用时 15 毫秒
1.
2.
3.
Conall T. Morgan Brigitte Mueller Varsha Thakur Vitor Guerra Callaghan Jull Luc Mertens Mark Friedberg Fraser Golding Mike Seed Steven E.S. Miner Edgar T. Jaeggi Cedric Manlhiot Lynne E. Nield 《The Canadian journal of cardiology》2019,35(4):453-461
Background
The purpose of the study was to evaluate the association between fetal echocardiographic measurements and the need for intervention (primary coarctation repair, staged coarctation repair, or catheter intervention) in prenatally diagnosed coarctation of the aorta.Methods
A single-centre retrospective cohort study (2005-2015) of 107 fetuses diagnosed with suspected coarctation of the aorta in the setting of an apex-forming left ventricle and antegrade flow across the mitral and aortic valves.Results
Median gestational age at diagnosis was 32 weeks (interquartile range, 23-35 weeks). Fifty-six (52%) did not require any neonatal intervention, 51 patients (48%) underwent a biventricular repair. In univariable analysis, an increase in ascending aorta (AAo) peak Doppler flow velocity (odds ratio [OR], 1.40 [95% confidence interval [CI], 1.05-1.91] per 20 cm/s; P = 0.03) was associated with intervention. No intervention was associated with larger isthmus size (OR, 0.23; P < 0.001), transverse arch diameter (OR, 0.23; P < 0.001), and aortic (OR, 0.72; P = 0.02), mitral (OR, 0.58; P = 0.001), and AAo (OR, 0.53; P < 0.001) z-scores. In multivariable analysis, higher peak AAo Doppler (OR, 2.51 [95% CI, 1.54-4.58] per 20 cm/s; P = 0.001) and younger gestational age at diagnosis (OR, 0.81 [95% CI, 0.70-0.93] per week; P = 0.005) were associated with intervention, whereas a higher AAo z-score (OR, 0.65 [95% CI, 0.43-0.94] per z; P = 0.029) and transverse arch dimension (OR, 0.44 [95% CI, 0.18-0.97]; P = 0.05) decreased the risk of intervention.Conclusions
In prenatally suspected coarctation, the variables associated with intervention comprised smaller AAo and transverse arch size, earlier gestational age at diagnosis, and the additional finding of a higher peak AAo Doppler. 相似文献4.
5.
After the interaction of estrogen with the ligand binding domain (LBD) of mouse estrogen receptor‐α (mERα) and hormone‐responsive elements of target genes, many nuclear proteins are recruited to regulate the expression of specific genes. Because it is not known which brain proteins interact with LBD or whether these proteins vary with age and sex, we used pull‐down assay and far Western blotting to detect five nuclear proteins of 160, 140, 87, 60, and 46 kD in the mouse brain. These interacting proteins were identified as PELP1, RIP140, PGC1α, BAF60, and ADA3, respectively. The level of PELP1, RIP140, PGC1α, and BAF60 decreased drastically in old compared with adult male mice, whereas the ADA3 level showed no significant change. PELP1, PGC1α, and BAF60 levels were lower in old male compared with female mice. Thus we report the identification and interaction of five nuclear proteins with mERα‐LBD, indicating their role in estrogen signaling and brain functions during aging. © 2009 Wiley‐Liss, Inc. 相似文献
6.
Modulation of cytokine production from an EpiOcular corneal cell culture model in response to Staphylococcus aureus superantigen 总被引:3,自引:0,他引:3
A Thakur PhD A Clegg MSc A Chauhan MSc MDP Willcox PhD 《Clinical & experimental ophthalmology》1997,25(4):43-45
The present study investigated the hypothesis that Staphylococcus aureus enterotoxin B (SEE) produces epithelial cell death and releases inflammatory cytokines that produce stromal infiltration during contact lens induced peripheral ulceration. Epithelial cells were incubated with different doses of SEB for various time periods. Culture supernatants were assayed for cytokines IL- lo, IL-6 and chemotactic agents IL-8 and LTB,. SEE induced the production of IL- I p and IL-8. Epithelial cells exposed for longer periods (48 h) with low concentrations of SEB produced significantly higher levels (N0.02) of IL-Ip and IL-8 (P<0.05) compared t o a 24 h exposure. SEB did not induce the production o f IL-6 and 相似文献
7.
Michael P. Steinmetz Thomas E. Mroz Ajit Krishnaney Michael Modic 《The spine journal》2009,9(12):967-971
BackgroundIn today's health-care environment, operational efficiency is intrinsic to balancing the need for increased productivity driven by rising costs and potentially decreasing reimbursement. Other operational factors kept constant, decreasing the time for a procedure can be viewed as one marker for increased efficiency.PurposeTo prospectively evaluate the time and operating room efficiency differences between the two methods for intraoperative level localization.Stydy designProspective nonrandomized study.Patient sampleProspective consecutive patients undergoing a single-level anterior cervical discectomy and fusion (ACDF) with plate and allograft.Outcomes measuresTime for performance and interpretation of intraoperative localization radiograph.MethodsThis is a prospective nonrandomized study of patients treated consecutively with a single-level ACDF with allograft and plating. All the patients underwent a conventional approach to the cervical spine. After exposure, a spinal needle was placed in the exposed intervertebral disc and a radiography was performed. Either a conventional or a digital radiography was used in each case.ResultsEighteen patients were enrolled in this study. Ten patients underwent localization with conventional radiography, whereas eight patients underwent localization with digital imaging. The mean time for conventional radiography was 823 seconds (standard deviation [SD], 159), and for digital, it was 100 seconds (SD, 34; p<.001).ConclusionsCurrent technology provides options for level localization. Digital imaging provides equally accurate information as conventional radiography in a significantly reduced amount of time. Image quality, ease or archival, and manipulation provided by digital radiography are superior to those by provided fluoroscopy. Keeping operational factors constant, decreasing the time for a procedure, and increasing the efficiency of the environment may be viewed as a surrogate for improving the cost basis for a procedure. 相似文献
8.
Subodh Varshney Sandesh Sharma Viniyendra Pamecha Ajit Sewkani Lalish Jhawar Vinod Narkhede Virendra Tewari Kailash Patel 《Indian journal of gastroenterology》2003,22(3):91-93
INTRODUCTION: Radiofrequency (RF) tissue ablation has been tried safely and effectively in the West as percutaneous local tissue ablation therapy. We present our experience with this technique in malignant lesions. METHODS: RF tumor ablation was done using an RF generator (Berchtold; Germany) generating 35-50 RF watts of power output. The RF needle was placed in the tumor under image guidance (n = 22) or at open surgery (n = 1). Around 1500 watts/cm3 RF energy was delivered to the tumor. Over 21 months, 23 patients underwent the procedure for 73 lesions, including metastatic liver lesions (n = 21) and locally advanced inoperable carcinoma of pancreas (n = 2). RESULTS: All lesions less than 3 cm in size (n = 15) and 39% of lesions 3-4 cm in size (17/44) had complete necrosis. Residual tumor was seen in 27/44 lesions (61%) 3-4 cm in size and in all 14 lesions more than 4 cm in size. There was no mortality or major morbidity. There were two minor complications (ascites 1, pleural effusion 1). Of 21 patients treated for liver metastases, 10 are still alive (6-month survival 19/21 [90%] and 12-month survival 11/17 [64.7%]). Only 2 of 32 (6.2%) lesions with complete necrosis had local recurrence. CONCLUSION: RF tumor ablation is a safe and effective local tissue ablative method in Indian patients. 相似文献
9.
10.
Ajit Sood Vandana Midha Neena Sood Manu Bansal 《Indian journal of gastroenterology》2006,25(6):283-285
BACKGROUND: The treatment of hepatitis C virus (HCV)-related cirrhosis is difficult due to high frequency of adverse effects. We retrospectively reviewed the case records of patients with HCV cirrhosis to evaluate the efficacy and tolerability of pegylated (peg) interferon and ribavirin treatment in these patients. METHODS: Medical records of 28 patients with HCV-related compensated cirrhosis were reviewed. The treatment protocol was a combination therapy of peg interferon alfa-2b (1 microg/Kg/week) plus oral ribavirin (10-12 mg/Kg/day). Primary endpoint was sustained virological response, with additional endpoints of drug tolerance, clinical or biochemical worsening and death. RESULTS: End-of-treatment virlogic response was seen in 24 of 28 patients (85%) and sustained virologic response in 15 of 28 (53%) patients. Biochemical end-of-treatment response and sustained response were seen in 20 and 16 patients (71% and 57%), respectively. Treatment had to be stopped in 3 patients due to decompensation of liver status in two and drug intolerance in one, while dose modification was required in two patients. CONCLUSIONS: Combination therapy with peg interferon plus ribavirin seems effective in patients with liver cirrhosis. High relapse rate, poor biochemical recovery and possibility of decompensation are issues that need to be kept in mind. 相似文献