全文获取类型
收费全文 | 4268篇 |
免费 | 261篇 |
国内免费 | 19篇 |
专业分类
耳鼻咽喉 | 42篇 |
儿科学 | 272篇 |
妇产科学 | 64篇 |
基础医学 | 395篇 |
口腔科学 | 116篇 |
临床医学 | 324篇 |
内科学 | 987篇 |
皮肤病学 | 145篇 |
神经病学 | 215篇 |
特种医学 | 141篇 |
外科学 | 650篇 |
综合类 | 85篇 |
一般理论 | 1篇 |
预防医学 | 183篇 |
眼科学 | 268篇 |
药学 | 376篇 |
中国医学 | 14篇 |
肿瘤学 | 270篇 |
出版年
2023年 | 61篇 |
2022年 | 164篇 |
2021年 | 238篇 |
2020年 | 133篇 |
2019年 | 174篇 |
2018年 | 211篇 |
2017年 | 172篇 |
2016年 | 188篇 |
2015年 | 172篇 |
2014年 | 258篇 |
2013年 | 300篇 |
2012年 | 352篇 |
2011年 | 306篇 |
2010年 | 173篇 |
2009年 | 137篇 |
2008年 | 223篇 |
2007年 | 165篇 |
2006年 | 139篇 |
2005年 | 120篇 |
2004年 | 99篇 |
2003年 | 67篇 |
2002年 | 54篇 |
2001年 | 48篇 |
2000年 | 48篇 |
1999年 | 38篇 |
1998年 | 21篇 |
1997年 | 23篇 |
1996年 | 10篇 |
1995年 | 17篇 |
1993年 | 16篇 |
1992年 | 41篇 |
1991年 | 24篇 |
1990年 | 34篇 |
1989年 | 33篇 |
1988年 | 34篇 |
1987年 | 26篇 |
1986年 | 20篇 |
1985年 | 28篇 |
1984年 | 21篇 |
1983年 | 10篇 |
1980年 | 8篇 |
1979年 | 21篇 |
1978年 | 13篇 |
1977年 | 7篇 |
1975年 | 8篇 |
1974年 | 13篇 |
1973年 | 14篇 |
1972年 | 8篇 |
1971年 | 8篇 |
1965年 | 7篇 |
排序方式: 共有4548条查询结果,搜索用时 15 毫秒
81.
82.
Ajit Sood Shiv Kumar Sarin Vandana Midha Syed Hissar Neena Sood Pankaj Bansal Manu Bansal 《Indian journal of gastroenterology》2012,31(5):232-236
Background and Aim
Epidemiological data on hepatitis C virus (HCV) infection from India are scanty. We conducted a population-based seroepidemiologic survey to estimate the prevalence of hepatitis C in Punjab state of northern India.Methods
A house-to-house survey was conducted in a defined population of 26,273 subjects. Information was gathered according to a predesigned questionnaire with socio-demographic characteristics (age, gender and substance abuse), family history of HCV infection, general health status, associated co-infection, immunization history and potential risk factors for HCV transmission. At the time of clinical evaluation, blood was tested for anti-HCV and those found positive were tested for HCV RNA.Results
Among 5,258 subjects screened, 272 were found to be anti-HCV positive (prevalence rate of 5.2?%); highest prevalence being noticed in 41?C60?years age group. Anti-HCV positive rate were not different among males and females. Sixty-seven subjects (1.3?%) were found to be HBsAg positive; four of these being co-infected (5.9?%). Various risk factors for acquiring HCV infection identified were history of surgery, dental treatment and unprotected sex. Other associations were strong family history of HCV positivity, alcohol consumption and diabetes mellitus.Conclusion
Chronic HCV infection is a major health problem in Punjab; it appears to be more common than HBV infection. Exercising safe health care related procedures should be emphasized in our country as main modes of transmission of infection identified were related to these. 相似文献83.
84.
Ruchi Goel Saurabh Kamal Sonam A. Bodh Sushil Kumar Jugal Kishore K.P.S. Malik Madhu Singh Smriti Bansal 《Journal of cranio-maxillo-facial surgery》2013,41(7):e111-e116
ObjectiveTo evaluate the efficacy and complications of lower eyelid suspension with the modified Safdarjung hospital technique using 5:0 polypropylene suture for punctal ectropion.Study designProspective case series.MethodThirty one eyelids in 19 patients with mild and moderate ectropion and all types of laxity including involutional and paralytic were included. All patients underwent lower eyelid suspension with the modified Safdarjung hospital technique. A 5:0 polypropylene suture was passed in the pre-tarsal plane between the attachments of the lateral and medial canthal tendons near their insertion at the orbital rim. Successful outcome was judged by the anatomical restoration of the apposition of the punctum to the globe in the upward gaze and the physiological relief of epiphora. The recurrence of lid laxity, overall lid/globe apposition and complications were also noted.ResultsAt 1 year follow up anatomical success was achieved in 28 (90%) patients and functional success noted in 27 (87%) patients. Recurrence of lid laxity was noted in 2 patients. There was a suture exposure in one case and a suture granuloma in another case. The results did not correlate to the degree of ectropion and type of laxity.ConclusionLower eyelid suspension using 5:0 polypropylene suture is a useful procedure for the treatment of involutional and paralytic punctal ectropion. It is simple and effective with minimal complications. However, the effect on scleral show and the concern related to suture material biodegradation over years needs to be further evaluated. 相似文献
85.
Aliasgar V. Moiyadi Prakash M. Shetty Abhishek Mahajan Amar Udare Epari Sridhar 《Acta neurochirurgica》2013,155(12):2217-2225
Background
Intraoperative imaging is increasingly being used in resection of brain tumors. Navigable three-dimensional (3D)-ultrasound is a novel tool for planning and guiding such resections. We review our experience with this system and analyze our initial results, especially with respect to malignant gliomas.Methods
A prospective database for all patients undergoing sononavigation-guided surgery at our center since this surgery’s introduction in June 2011 was queried to retrieve clinical data and technical parameters. Imaging was reviewed to categorize tumors based on enhancement and resectability. Extent of resection was also assessed.Results
Ninety cases were operated and included in this analysis, 75 % being gliomas. The 3D ultrasound mode was used in 87 % cases (alone in 40, and combined in 38 cases). Use of combined mode function [ultrasound (US) with magnetic resonance (MR) images] facilitated orientation of anatomical data. Intraoperative power Doppler angiography was used in one-third of the cases, and was extremely beneficial in delineating the vascular anatomy in real-time. Mean duration of surgery was 4.4 hours. Image resolution was good or moderate in about 88 % cases. The use of the intraoperative imaging prompted further resection in 59 % cases. In the malignant gliomas (51 cases), gross-total resection was achieved in 47 % cases, increasing to 88 % in the “resectable” subgroup.Conclusions
Navigable 3D US is a versatile, useful and reliable intraoperative imaging tool in resection of brain tumors, especially in resource-constrained settings where Intraoperative MR (IOMR) is not available. It has multiple functionalities that can be tailored to suit the procedure and the experience of the surgeon. 相似文献86.
87.
88.
Thethi I Bansal V Khan H Hoppensteadt D Fareed J 《Clinical and applied thrombosis/hemostasis》2012,18(5):534-537
Patients with end-stage renal disease (ESRD) are known to have an elevation of a variety of abnormal thrombotic and inflammatory markers associated with high cardiovascular mortality. Vascular endothelial growth factor (VEGF) is also dysregulated in ESRD but not much is known about the serum levels of VEGF in patients with ESRD. Published reports suggest that elevated levels of VEGF may be protective to the kidney during periods of acute injury and may maintain local glomerular function. Impaired production of VEGF may lead to proteinuria, hypertension, and thrombotic microangiopathy. However, its role in chronic kidney disease or ESRD remains undefined. In our study, we analyzed blood samples of 52 patients with ESRD on stable hemodialysis regimen and measured predialysis serum levels of VEGF and compared these with blood samples obtained from 50 healthy volunteers in order to study differences between baseline levels of VEGF and also attempted to determine its role in ESRD-related cardiovascular mortality. 相似文献
89.
90.
Rehana Khan Abhishek Sharma Raghul Ravikumar Avani Parekh Ramyaa Srinivasan Ronnie Jacob George Rajiv Raman 《Investigative ophthalmology & visual science》2021,62(7)
PurposeTo study the association between gut microbial abundance and sight-threatening diabetic retinopathy among patients with a history of type 2 diabetes mellitus.MethodsAn observational case-control study was performed using a sample population of diabetics referred to a tertiary eye institute. Sample subjects were identified as cases if they were diagnosed with sight-threatening diabetic retinopathy and controls if they were not but had at least a 10-year history of diabetes. Fecal swabs for all patients were collected for enumeration and identification of sequenced gut microbes. Statistical analyses were performed to associate the clinically relevant Bacteroidetes to Firmicutes relative abundance ratio (B/F ratio) with sight-threatening diabetic retinopathy and an optimal cutoff value for the ratio was identified using Youden''s J statistics.ResultsA sample size of 58 diabetic patients was selected (37 cases, 21 controls). No statistically significant difference in the relative abundance among the predominant phyla between the groups were found. In our univariate analysis, the B/F ratio was elevated in cases compared to controls (cases, 1.45; controls, 0.94; P = 0.049). However, this statistically significant difference was not seen in our multivariate regression model. Optimal cutoff value of 1.05 for the B/F ratio was identified, and significant clustering of cases above this value was noted in beta diversity plotting.ConclusionsNo difference in gut microbial abundance for any particular phylum was noted between the control and diseased population. Increased gut microbial B/F ratio can be a potential biomarker for the development of sight-threatening diabetic retinopathy among type 2 diabetic patients. 相似文献