全文获取类型
收费全文 | 56155篇 |
免费 | 3094篇 |
国内免费 | 598篇 |
专业分类
耳鼻咽喉 | 985篇 |
儿科学 | 630篇 |
妇产科学 | 825篇 |
基础医学 | 9754篇 |
口腔科学 | 1352篇 |
临床医学 | 4885篇 |
内科学 | 10544篇 |
皮肤病学 | 1870篇 |
神经病学 | 3981篇 |
特种医学 | 2968篇 |
外科学 | 7471篇 |
综合类 | 213篇 |
现状与发展 | 1篇 |
一般理论 | 17篇 |
预防医学 | 2711篇 |
眼科学 | 1230篇 |
药学 | 4983篇 |
中国医学 | 624篇 |
肿瘤学 | 4803篇 |
出版年
2023年 | 428篇 |
2022年 | 1326篇 |
2021年 | 2056篇 |
2020年 | 985篇 |
2019年 | 1288篇 |
2018年 | 1665篇 |
2017年 | 1240篇 |
2016年 | 1757篇 |
2015年 | 2559篇 |
2014年 | 3058篇 |
2013年 | 3487篇 |
2012年 | 5312篇 |
2011年 | 4806篇 |
2010年 | 2802篇 |
2009年 | 2360篇 |
2008年 | 3415篇 |
2007年 | 3093篇 |
2006年 | 2652篇 |
2005年 | 2352篇 |
2004年 | 2024篇 |
2003年 | 1692篇 |
2002年 | 1435篇 |
2001年 | 1363篇 |
2000年 | 1262篇 |
1999年 | 906篇 |
1998年 | 362篇 |
1997年 | 250篇 |
1996年 | 208篇 |
1995年 | 176篇 |
1994年 | 148篇 |
1993年 | 132篇 |
1992年 | 332篇 |
1991年 | 316篇 |
1990年 | 280篇 |
1989年 | 258篇 |
1988年 | 247篇 |
1987年 | 248篇 |
1986年 | 177篇 |
1985年 | 165篇 |
1984年 | 119篇 |
1983年 | 111篇 |
1982年 | 55篇 |
1981年 | 58篇 |
1979年 | 81篇 |
1978年 | 68篇 |
1975年 | 50篇 |
1974年 | 60篇 |
1973年 | 51篇 |
1972年 | 50篇 |
1970年 | 49篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
Sung Wook Park Jeong-Min Hwang 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2015,253(1):135-141
Purpose
The aim of the study was to evaluate the relationship between visual function and retinal nerve fiber layer thickness (RNFLT) determined using Stratus optical coherence tomography (OCT) in patients with autosomal dominant optic atrophy (ADOA).Methods
The study was a retrospective, institutional, and comparative case series. Thirty-six consecutive patients with ADOA and 72 age-matched normal controls were compared with regard to RNFLT, best-corrected visual acuity (BCVA), and visual field.Results
The relative reduction of RNFLT of ADOA patients was most evident in the temporal quadrant (56.8 %), followed by the inferior (35.5 %), superior (27.2 %), and nasal quadrants (26.4 %). In ADOA patients, BCVA decreased with RNFL thinning (p?<?0.001), and was not related to age (p?=?0.210). Papillomacular bundle RNFLT decreased with age throughout the study period of 3.7?±?2.3 years (?3.83?±?9.96 μm, p?=?0.017). The presence of a superotemporal central scotoma (61.1 %) was related to decreased inferotemporal RNFLT (7 and 8 o’clock, p?=?0.016 and p?=?0.036, respectively).Conclusions
The papillomacular bundle RNFL of ADOA is most vulnerable and progressively damaged with age, despite early temporal RNFL loss. Early loss of inferior temporal RNFL in ADOA is related to superotemporal central scotoma.993.
994.
Min?Hee?SuhEmail author Byeong?Wook?Yoo Ki?Ho?Park Jung?Yup?Kim Hyunjoong?Kim Hee?Chan?Kim 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2015,253(6):925-934
Background
To evaluate the correlation between the depth and area of retinal nerve fiber layer (RNFL) defect, as measured on an RNFL map of spectral-domain optical coherence tomography (SD-OCT).Methods
The RNFL of 472 glaucoma subjects and of 217 healthy subjects was imaged by an SD-OCT. RNFL defect depth and area on the RNFL map were expressed as an RNFL defect depth percentage index (RDPI) and an RNFL defect area index (RDAI), respectively, according to the following two formulas: 100×[1–{summation of thicknesses of RNFL defects/summation of thicknesses of upper 95th percentile range of age-matched healthy subjects in areas corresponding to defects}]; 100×[number of superpixels of RNFL defects/(46?×?46–superpixels inside optic disc or β zone parapapillary atrophy)]. The best-fitting model describing the relationship between the two parameters was derived by fractional polynomial analysis.Results
Logarithmic fit was determined to be the best-fitting model in describing the relationship of the RDPI against the RDAI (y?=?53.4?+?3.7 ln(x) and y?=?50.9?+?5.9 ln(x) in superior and inferior hemifields, respectively). The expected RDAIs at the point where the RDPI and RDAI rates of change were the same were 3.7 and 5.9 %; the corresponding upper 95 % confidence interval limits of the RDPI 59.0 and 61.8 % in the superior and inferior hemifields, respectively.Conclusions
The correlation between the RNFL defect depth and area, as derived from the RNFL map, was best described by the logarithmic fit. Changes were more marked in depth than in area, especially for mild localized defects.995.
996.
Purpose
To investigate peripheral lamina cribrosa depth (PLCD) and its vertical-horizontal difference in eyes with primary open-angle glaucoma (POAG).Methods
Patients with POAG (n=90 eyes) and age-matched healthy individuals (n=90 eyes) underwent swept-source optical coherence tomography (SS-OCT) scans centered at the optic discs. The PLCD was defined as the vertical distance between the most peripheral visible end of anterior lamina cribrosa (LC) surface and the reference plane connecting the Bruch''s membrane openings. The PLCD in each quadrant region and the vertical-horizontal PLCD difference were compared between the POAG and healthy eyes. The clinical factors associated with increased PLCD were evaluated.Results
The PLCD was significantly larger in the POAG eyes than the control eyes at the horizontal (P=0.034) and vertical (P=0.001) meridians. The vertical PLCD was significantly larger than the horizontal PLCD, both in the POAG eyes (P<0.001) and in the control eyes (P=0.003). However, the vertical-horizontal PLCD difference was significantly larger in the POAG eyes (47±60 μm) than in the control eyes (18±54 μm, P=0.001). Multivariate regression showed a significant association of male gender (P=0.005), increased baseline IOP (P=0.043), and decreased MD of VF (P=0.025) with increased PLCD.Conclusions
The peripheral LC was displaced more posteriorly in the POAG eyes compared with the age-matched healthy eyes. In the POAG eyes, the peripheral LC was displaced more posteriorly at the vertical meridian than at the horizontal meridian. The peripheral LC in the vertical meridian might have increased IOP-related strain (deformation) compared with horizontal meridian in glaucomatous eyes. 相似文献997.
Jaeki Jeong Haeyeon Kim Yung Jin Yoon Bright Walker Seyeong Song Jungwoo Heo Song Yi Park Jae Won Kim Gi-Hwan Kim Jin Young Kim 《RSC advances》2018,8(43):24110
We herein demonstrate n-i-p-type planar heterojunction perovskite solar cells employing spin-coated ZnO nanoparticles modified with various alkali metal carbonates including Li2CO3, Na2CO3, K2CO3 and Cs2CO3, which can tune the energy band structure of ZnO ETLs. Since these metal carbonates doped on ZnO ETLs lead to deeper conduction bands in the ZnO ETLs, electrons are easily transported from the perovskite active layer to the cathode electrode. The power conversion efficiency of about 27% is improved due to the incorporation of alkali carbonates in ETLs. As alternatives to TiO2 and n-type metal oxides, electron transport materials consisting of doped ZnO nanoparticles are viable ETLs for efficient n-i-p planar heterojunction solar cells, and they can be used on flexible substrates via roll-to-roll processing.Planar formamidinium perovskite solar cells have been fabricated with an alkali carbonate-doped zinc oxide layer. 相似文献
998.
Jin-Won Noh Young Dae Kwon Sieun Yu Hyunchun Park Jong-Min Woo 《Yebang Ŭihakhoe chi》2015,48(1):62-71
Objectives:
This study aimed to investigate North Korean refugees’ knowledge of mental illnesses and treatments and analyze the factors affecting this knowledge.Methods:
Subjects were selected via a snowball sampling method, and the survey outcomes of 152 North Korean refugee participants were analyzed. The factors affecting knowledge of mental illnesses were analyzed via a regression analysis by constructing a multivariate model with mental illness knowledge score as the dependent variable.Results:
The North Korean refugees’ mental illness scores ranged from 3 to 24 points, with an average score of 13.0. Regarding the factors that influence mental illness knowledge, the subjects with South Korean spouses and those who had spent more time in South Korea had higher knowledge scores. Furthermore, the subjects who considered the mental health of North Korean refugees to be a serious issue revealed lower knowledge scores than those who did not believe it was a serious issue. The subjects who visit psychiatric clinics showed higher knowledge scores than those who do not. The South Korean subjects who had at least a college education exhibited higher scores than did those without advanced education. The subjects who are satisfied with life in South Korea manifested a higher mental illness knowledge score than those who are not.Conclusions:
This study is significant as being the first study to ever measure and evaluate the level of North Korean refugees’ knowledge of mental illnesses. In addition, the evaluations of North Korean refugees’ mental illness knowledge and influencing factors while residing in South Korea created basic data that formed the foundation of an effort to enhance mental health literacy and provide proper mental health services. The results of this study can be utilized to solve mental health problems that might frequently occur during the unification process of North and South Korea in the future. 相似文献999.
Quang T. Nguyen Eun Joo Lee Melinda Gingman Huang Young In Park Aashish Khullar Raymond A. Plodkowski 《American Health & Drug Benefits》2015,8(1):30-40
Background
Thyroid cancer is the most common malignancy of the endocrine system, representing 3.8% of all new cancer cases in the United States and is the ninth most common cancer overall. The American Cancer Society estimates that 62,450 people in the United States will be diagnosed with thyroid cancer in 2015, and 1950 deaths will result from the disease.Objective
To review the current approach to the diagnosis and treatment of patients with thyroid cancer.Discussion
Over the past 3 decades, there has been a dramatic increase in the number of people diagnosed with thyroid cancer, which may be attributable to the wide use of imaging studies, including ultrasounds, computed tomography, magnetic resonance imaging, and positron emission tomography scans that incidentally detect thyroid nodules. Thyroid cancer is divided into several main types, with papillary thyroid cancer being the most common. The treatment options for patients with thyroid cancer include the surgical removal of the entire thyroid gland (total thyroidectomy), radioactive iodine therapy, and molecular-targeted therapies with tyrosine kinase inhibitors. This article summarizes the diagnosis and treatment of thyroid cancer, with recommendations from the American Thyroid Association regarding thyroid nodules and differentiated thyroid cancer. Recently approved drugs and treatment trends are also explored.Conclusion
The prognosis and treatment of thyroid cancer depend on the tumor type and its stage at the time of diagnosis. Many thyroid cancers remain stable, microscopic, and indolent. The increasing treatment options for patients with thyroid cancer, including therapies that were recently approved by the US Food and Drug Administration, have kept the mortality rate from this malignancy low, despite the increase in its incidence. Early diagnosis and appropriate treatment can improve prognosis and reduce mortality. 相似文献1000.