全文获取类型
收费全文 | 44822篇 |
免费 | 4954篇 |
国内免费 | 367篇 |
专业分类
耳鼻咽喉 | 1071篇 |
儿科学 | 1204篇 |
妇产科学 | 660篇 |
基础医学 | 4624篇 |
口腔科学 | 879篇 |
临床医学 | 5364篇 |
内科学 | 9411篇 |
皮肤病学 | 1039篇 |
神经病学 | 3981篇 |
特种医学 | 1947篇 |
外科学 | 8950篇 |
综合类 | 341篇 |
现状与发展 | 2篇 |
一般理论 | 38篇 |
预防医学 | 3317篇 |
眼科学 | 1169篇 |
药学 | 2352篇 |
中国医学 | 29篇 |
肿瘤学 | 3765篇 |
出版年
2024年 | 134篇 |
2023年 | 711篇 |
2022年 | 510篇 |
2021年 | 1197篇 |
2020年 | 1248篇 |
2019年 | 1029篇 |
2018年 | 1592篇 |
2017年 | 1348篇 |
2016年 | 1557篇 |
2015年 | 1536篇 |
2014年 | 2277篇 |
2013年 | 2653篇 |
2012年 | 3119篇 |
2011年 | 3037篇 |
2010年 | 2164篇 |
2009年 | 2115篇 |
2008年 | 2633篇 |
2007年 | 2668篇 |
2006年 | 2669篇 |
2005年 | 2573篇 |
2004年 | 2303篇 |
2003年 | 2137篇 |
2002年 | 2049篇 |
2001年 | 432篇 |
2000年 | 269篇 |
1999年 | 419篇 |
1998年 | 639篇 |
1997年 | 560篇 |
1996年 | 542篇 |
1995年 | 562篇 |
1994年 | 351篇 |
1993年 | 293篇 |
1992年 | 239篇 |
1991年 | 237篇 |
1990年 | 145篇 |
1989年 | 200篇 |
1988年 | 166篇 |
1987年 | 139篇 |
1986年 | 163篇 |
1985年 | 148篇 |
1984年 | 167篇 |
1983年 | 144篇 |
1982年 | 167篇 |
1981年 | 127篇 |
1980年 | 126篇 |
1979年 | 64篇 |
1978年 | 76篇 |
1977年 | 85篇 |
1976年 | 54篇 |
1975年 | 67篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
993.
T Bailey A Chang PD Rosenblit L Jones G Teft S Setford J Mahoney 《Diabetes technology & therapeutics》2012,14(8):701-709
Abstract Background: OneTouch(?) Verio(?) test strips (LifeScan Inc., Milpitas, CA) are designed to minimize error when used in blood glucose monitoring systems. These strips have a specialized architecture and incorporate a sophisticated waveform and proprietary algorithm. Materials and Methods: Performance of OneTouch Verio test strips was assessed in the laboratory in the presence of a wide range of patient, environmental, and pharmacologic factors. A clinical evaluation was conducted in which 296 patients and healthcare professionals (HCPs) performed glucose testing using OneTouch Verio test strips and OneTouch VerioIQ meters. Results: In the laboratory study, OneTouch Verio test strip results achieved a high level of performance over a wide range of hematocrit (19-61%), temperature (5-45(°)C), humidity (10-90% relative humidity), and altitude (0-3,048?m) conditions. Performance was not affected by 22 of 23 chemical compounds. In the clinical study, 100% (31/31) of lay-user test results were within ±10?mg/dL of reference values for blood glucose <75?mg/dL. At blood glucose ≥75?mg/dL, 99.2% (243/245) were within ±15% of reference values. A feature of the VerioIQ meter, PatternAlert(?) Technology, was correctly used and positively evaluated by >98% of lay users. Conclusions: OneTouch Verio test strips are accurate and precise over a wide range of patient, environmental, and pharmacologic conditions. In addition, lay-users were able to successfully use the OneTouch VerioIQ PatternAlert Technology without HCP training. 相似文献
994.
Timothy T. Xu Yi-Ju Li Natalie A. Afshari Ross A. Aleff Tommy A. Rinkoski Sanjay V. Patel Leo J. Maguire Albert O. Edwards William L. Brown Michael P. Fautsch Eric D. Wieben Keith H. Baratz 《Investigative ophthalmology & visual science》2021,62(1)
PurposeTo characterize inheritance, penetrance, and trinucleotide repeat expansion stability in Fuchs endothelial corneal dystrophy (FECD).MethodsOne thousand unrelated and related subjects with and without FECD were prospectively recruited. CTG18.1 repeat length (CTG18.1L) was determined via short tandem repeat assay and Southern blotting of leukocyte DNA. Multivariable logistic regression and generalized estimating equation models were employed.ResultsThere were 546 unrelated FECD cases (67.6% female; 70 ± 10 years) and 235 controls (63.8% female; 73 ± 8 years; all ≥ 50 years). CTG18.1 expansion (CTG18.1exp+) was observed in 424 (77.7%) cases and 18 (7.7%) controls (P = 2.48 × 10–44). CTG18.1 expansion was associated with FECD severity (P = 5.62 × 10–7). The family arm of the study included 331 members from 112 FECD-affected families; 87 families were CTG18.1exp+. Autosomal dominant inheritance with variable expression of FECD was observed, regardless of expansion status. FECD penetrance of CTG18.1 expansion increased with age, ranging from 44.4% in the youngest (19–46 years) to 86.2% in the oldest (64–91 years) age quartiles. Among 62 parent–offspring transmissions of CTG18.1exp+, 48 (77.4%) had a change in CTG18.1L ≤ 10 repeats, and eight (12.9%) were ≥50 repeats, including five large expansions (∼1000–2000 repeats) that contracted. Among 44 offspring who did not inherit the CTG18.1exp+ allele, eight (18.2%) exhibited FECD.ConclusionsCTG18.1 expansion was highly associated with FECD but demonstrated incomplete penetrance. CTG18.1L instability occurred in a minority of parent–offspring transmissions, with large expansions exhibiting contraction. The observation of FECD without CTG18.1 expansion among family members in CTG18.1exp+ families highlights the complexity of the relationship between the FECD phenotype and CTG18.1 expansion. 相似文献
995.
Padmaja Sankaridurg Nina Tahhan Himal Kandel Thomas Naduvilath Haidong Zou Kevin D. Frick Srinivas Marmamula David S. Friedman Ecosse Lamoureux Jill Keeffe Jeffrey J. Walline Timothy R. Fricke Vilas Kovai Serge Resnikoff 《Investigative ophthalmology & visual science》2021,62(5)
The global burden of myopia is growing. Myopia affected nearly 30% of the world population in 2020 and this number is expected to rise to 50% by 2050. This review aims to analyze the impact of myopia on individuals and society; summarizing the evidence for recent research on the prevalence of myopia and high myopia, lifetime pathological manifestations of myopia, direct health expenditure, and indirect costs such as lost productivity and reduced quality of life (QOL). The principal trends are a rising prevalence of myopia and high myopia, with a disproportionately greater increase in the prevalence of high myopia. This forecasts a future increase in vision loss due to uncorrected myopia as well as high myopia-related complications such as myopic macular degeneration. QOL is affected for those with uncorrected myopia, high myopia, or complications of high myopia. Overall the current global cost estimates related to direct health expenditure and lost productivity are in the billions. Health expenditure is greater in adults, reflecting the added costs due to myopia-related complications. Unless the current trajectory for the rising prevalence of myopia and high myopia change, the costs will continue to grow. The past few decades have seen the emergence of several novel approaches to prevent and slow myopia. Further work is needed to understand the life-long impact of myopia on an individual and the cost-effectiveness of the various novel approaches in reducing the burden. 相似文献
996.
Kyoko Ohno-Matsui Pei-Chang Wu Kenji Yamashiro Kritchai Vutipongsatorn Yuxin Fang Chui Ming Gemmy Cheung Timothy Y. Y. Lai Yasushi Ikuno Salomon Yves Cohen Alain Gaudric Jost B. Jonas 《Investigative ophthalmology & visual science》2021,62(5)
Pathologic myopia is a major cause of visual impairment worldwide. Pathologic myopia is distinctly different from high myopia. High myopia is a high degree of myopic refractive error, whereas pathologic myopia is defined by a presence of typical complications in the fundus (posterior staphyloma or myopic maculopathy equal to or more serious than diffuse choroidal atrophy). Pathologic myopia often occurs in eyes with high myopia, however its complications especially posterior staphyloma can also occur in eyes without high myopia.Owing to a recent advance in ocular imaging, an objective and accurate diagnosis of pathologic myopia has become possible. Especially, optical coherence tomography has revealed novel lesions like dome-shaped macula and myopic traction maculopathy. Wide-field optical coherence tomography has succeeded in visualizing the entire extent of large staphylomas. The effectiveness of new therapies for complications have been shown, such as anti-VEGF therapies for myopic macular neovascularization and vitreoretinal surgery for myopic traction maculopathy.Myopia, especially childhood myopia, has been increasing rapidly in the world. In parallel with an increase in myopia, the prevalence of high myopia has also been increasing. However, it remains unclear whether or not pathologic myopia will increase in parallel with an increase of myopia itself. In addition, it has remained unclear whether genes responsible for pathologic myopia are the same as those for myopia in general, or whether pathologic myopia is genetically different from other myopia. 相似文献
997.
Michael R. Jaff DO Mark Bates MD Timothy Sullivan MD Jeffrey Popma MD Xingyu Gao MS Margo Zaugg RN BSN Patrick Verta MS Stat DVM MD 《Catheterization and cardiovascular interventions》2012,80(3):343-350
Background : Atherosclerotic renal artery stenosis (ARAS) causes hypertension (HTN) and threatens renal function (RF). The HERCULES Trial is a prospective, multicenter trial of renal stenting in patients with uncontrolled HTN and ARAS evaluating the safety and effectiveness of the RX Herculink Elite Renal Stent System (Abbott Vascular, Santa Clara, CA). Results : Mean systolic blood pressure (SBP) at baseline was 162 mm Hg. Nearly 70% of patients were receiving three or more antihypertensive medications (mean 3.4 medications per patient). Baseline serum creatinine was 1.2 ± 0.4 and 61.5% of subjects had estimated glomerular filtration <60. The restenosis rate was 10.5% at 9 months. The study device, procedure, and clinical success rates were 96.0, 99.2, and 98.0%, respectively. Freedom from major adverse events was 94.8%. At 9 months, the mean SBP significantly decreased (mean 145, paired t test P < 0.0001) after stenting with no change in medications. There was no correlation between SBP reduction and baseline BNP or BNP reduction. 相似文献
998.
999.
Manuel A. Gonzalez MD MPH Itsik Ben‐Dor MD Michael A. Gaglia Jr. MD MSc Rebecca Torguson MPH Hirity Shimellis BS Anh Bui MD William O. Suddath MD Augusto D. Pichard MD Lowell F. Satler MD Ron Waksman MD 《Catheterization and cardiovascular interventions》2012,79(5):843-848
Objectives: This study aimed to test whether advanced cardiovascular injection (ACI) via 4 French (Fr) catheters is more advantageous than manual injection with 6 Fr catheters. Background: For coronary angiography, proponents of contrast media ACI believe it utilizes smaller‐diameter catheters when compared with manual injection, without compromising the quality of the angiogram, and has the potential to reduce the amount of contrast used and lessen the use of closure devices. Methods: In a prospective study, 200 consecutive patients referred for elective coronary angiography were randomized to standard 6 Fr catheters with manual injection versus 4 Fr catheters with ACI. The study's primary endpoint is the quality of the coronary angiogram. Secondary endpoints include groin complications, utilization of closure devices, and volume of contrast media. Thirty‐six patients who underwent ad hoc percutaneous coronary intervention were excluded from the analysis. Results: The final analysis included 80 patients treated with 4 Fr catheters with ACI and 84 patients treated with 6 Fr catheters with manual injection. The groups had similar demographic and clinical characteristics. The quality of the angiogram was similar between groups with the exception of more left coronary sinus flush with 4 Fr catheters (3.57 ± 1.1 vs. 2.98 ± 0.9, P < 0.001) and less closure device use with 4 Fr (25 vs. 71.4%, P < 0.01) compared to 6 Fr catheters. The procedure duration, volume of contrast used, vascular complications, and time to ambulation were similar between groups (all P > 0.05). Conclusions: 4 Fr diagnostic catheters with ACI offer similar quality coronary angiograms, similar rates of vascular complications, procedure duration, contrast used, and time to ambulation, but have a significantly lesser need for closure devices compared to the 6 Fr system with manual injection. © 2011 Wiley‐Liss, Inc. 相似文献