全文获取类型
收费全文 | 576022篇 |
免费 | 39172篇 |
国内免费 | 11998篇 |
专业分类
耳鼻咽喉 | 5621篇 |
儿科学 | 14806篇 |
妇产科学 | 10338篇 |
基础医学 | 57002篇 |
口腔科学 | 13192篇 |
临床医学 | 53553篇 |
内科学 | 78103篇 |
皮肤病学 | 8570篇 |
神经病学 | 36003篇 |
特种医学 | 17980篇 |
外国民族医学 | 33篇 |
外科学 | 66933篇 |
综合类 | 75303篇 |
现状与发展 | 29篇 |
一般理论 | 37篇 |
预防医学 | 51484篇 |
眼科学 | 8960篇 |
药学 | 57595篇 |
424篇 | |
中国医学 | 43754篇 |
肿瘤学 | 27472篇 |
出版年
2023年 | 9602篇 |
2022年 | 16052篇 |
2021年 | 23588篇 |
2020年 | 20442篇 |
2019年 | 27875篇 |
2018年 | 25211篇 |
2017年 | 20666篇 |
2016年 | 17417篇 |
2015年 | 16976篇 |
2014年 | 28129篇 |
2013年 | 32576篇 |
2012年 | 26879篇 |
2011年 | 33088篇 |
2010年 | 23076篇 |
2009年 | 22403篇 |
2008年 | 23593篇 |
2007年 | 24584篇 |
2006年 | 22179篇 |
2005年 | 20193篇 |
2004年 | 17133篇 |
2003年 | 14908篇 |
2002年 | 12543篇 |
2001年 | 11798篇 |
2000年 | 11038篇 |
1999年 | 10069篇 |
1998年 | 8587篇 |
1997年 | 7657篇 |
1996年 | 6264篇 |
1995年 | 5486篇 |
1994年 | 5364篇 |
1993年 | 4299篇 |
1992年 | 4185篇 |
1991年 | 3688篇 |
1990年 | 3351篇 |
1989年 | 2774篇 |
1988年 | 2718篇 |
1987年 | 2323篇 |
1986年 | 2060篇 |
1985年 | 6009篇 |
1984年 | 7118篇 |
1983年 | 5161篇 |
1982年 | 5599篇 |
1981年 | 5145篇 |
1980年 | 4640篇 |
1979年 | 4223篇 |
1978年 | 3567篇 |
1977年 | 2823篇 |
1976年 | 3135篇 |
1975年 | 2488篇 |
1974年 | 2139篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
71.
目的:探讨血化瘀方联合针灸治疗对脑梗后遗症患者脑血管血液流变动力学及神经功能的影响。方法:选取2016年1月至2017年1月沈阳市第二中医医院收治脑梗后遗症患者120例作为研究对象,对照组61例患者接受针灸治疗;观察组59例患者接受活血化瘀方联合针灸治疗。2组连续治疗30 d。比较2组患者脑血流流变学指标、神经功能评分、中医证候积分、临床疗效。结果:治疗前2组患者脑部平均血流速度、左侧椎动脉血流量、右侧椎动脉血流量、基底动脉血流量比较,差异无统计学意义(P 0. 05)。治疗后观察组患者脑部平均血流速度、左侧椎动脉血流量、右侧椎动脉血流量、基底动脉血流量大于对照组(P 0. 05)。治疗前2组患者NIHSS评分、MMSE评分比较,差异无统计学意义(P 0. 05)。治疗后观察组患者NIHSS评分显著低于对照组,MMSE评分高于对照组(P 0. 05)。治疗前2组患者头晕目眩、语言謇涩、半身不遂、患侧麻木、舌苔白腻证候评分比较,差异无统计学意义(P 0. 05)。治疗后研究患者头晕目眩、语言謇涩、半身不遂、患侧麻木、舌苔白腻证候评分显著低于对照组(P 0. 05)。2组患者临床疗效比较,差异有统计学意义(Z=-5. 626,P=0. 000)。结论:活血化瘀方联合针灸能改善脑梗后遗症患者脑血管血液流变动力学指标,保护神经功能。 相似文献
72.
Adjuvant irradiation is the standard treatment after breast conservative surgery. Normofractionated regimen with an overall treatment time of 5 to 6 weeks is often considered as a limiting factor for irradiation compliance. In order to answer this issue, moderate and more recently extreme hypofractionated protocols appeared. We report here oncological outcomes and toxicity of hypofractionated breast irradiation. After defining the frame of moderate and extreme hypofractionated breast irradiations based on overall treatment time, patient selection criteria were listed. According to their levels of proof, the results of moderate and extreme hypofractionated breast irradiation were analysed. Overall treatment time for moderate hypofractionated breast irradiation ranged from 3 to 4 weeks, while for extreme hypofractionated breast irradiation, it was less than 1 week. For moderate hypofractionated breast irradiation, whole breast irradiation was currently performed with or without lymph node irradiation. Moderate hypofractionated breast irradiation has proven to be as safe and as efficient as normofractionated breast irradiation with level IA evidence. For extreme hypofractionated breast irradiation, phase III randomized trials confirmed that accelerated partial breast irradiation was non-inferior in terms of local control compared to normofractionated whole breast irradiation (with external beam radiation therapy and multicatheter brachytherapy), with similar acute and late toxicity. While the use of intraoperative breast irradiation remains under debate, new very accelerated partial breast irradiation (overall treatment time not exceeding 2 days) protocols emerged with encouraging results. Accelerated partial breast irradiation is warranted for extreme hypofractionated breast irradiation and is indicated for low-risk breast cancers. Moderate and extreme hypofractionated breast irradiation regimens are validated and can be routinely proposed according to patient selection criteria. 相似文献
73.
目的:观察理筋通督手法治疗颈性眩晕的临床疗效。方法:将120例颈性眩晕患者随机分成3组,理筋通督组、传统手法组及安慰剂组。理筋通督组采用理筋通督手法;传统手法组采用传统手法;安慰剂组口服维生素C。结果:理筋通督手法可显著减缓患者基底动脉舒张期最低血流速度(P0.05)。理筋通督组有效率为93.67%,传统手法组有效率为67.5%,安慰剂组有效率为17.5%,3组比较差异有统计学意义(P0.05),理筋通督组明显优于其他两组。结论:理筋通督手法治疗颈性眩晕临床疗效显著。 相似文献
74.
Xiying Fan Glen A. Bjerke Kent Riemondy Li Wang Rui Yi 《Molecular carcinogenesis》2019,58(12):2241-2253
MicroRNAs (miRNAs) play important roles in prostate cancer development. However, it remains unclear how individual miRNAs contribute to the initiation and progression of prostate cancer. Here we show that a basal layer‐enriched miRNA is required for prostate tumorigenesis. We identify miR‐205 as the most highly expressed miRNA and enriched in the basal cells of the prostate. Although miR‐205 is not required for normal prostate development and homeostasis, genetic deletion of miR‐205 in a Pten null tumor model significantly compromises tumor progression and does not promote metastasis. In Pten null basal cells, loss of miR‐205 attenuates pAkt levels and promotes cellular senescence. Furthermore, although overexpression of miR‐205 in prostate cancer cells with luminal phenotypes inhibits cell growth in both human and mouse, miR‐205 has a minimal effect on the growth of a normal human prostate cell line. Taken together, we have provided genetic evidence for a requirement of miR‐205 in the progression of Pten null‐induced prostate cancer. 相似文献
75.
Tonya J.H. White 《Journal of the American Academy of Child and Adolescent Psychiatry》2019,58(11):1042-1050
76.
Daniel Schar Pawin Padungtod Nguyen Tung Michael OLeary Wantanee Kalpravidh Filip Claes 《Influenza and other respiratory viruses》2019,13(6):618-621
Among the chief limitations in achieving early detection and control of animal‐origin influenza of pandemic potential in high‐risk livestock populations is the existing lag time between sample collection and diagnostic result. Advances in molecular diagnostics are permitting deployment of affordable, rapid, highly sensitive, and specific point‐of‐capture assays, providing opportunities for targeted surveillance driving containment strategies with potentially compelling returns on investment. Interrupting disease transmission at source holds promise of disrupting cycles of animal‐origin influenza incursion to endemicity and limiting impact on animal production, food security, and public health. Adoption of new point‐of‐capture diagnostics should be undertaken in the context of promoting robust veterinary services systems and parallel support for operationalizing pre‐authorized plans and communication strategies that will ensure that the full potential of these new platforms is realized. 相似文献
77.
This study is focussed on micro-encapsulation of essential oils in polylactic acid (PLA) and a poly(methyl methacrylate) (PMMA) matrix as well as blends of the same. Microspheres were prepared by the solvent evaporation technique and characterised by scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and Fourier transform infra-red spectroscopy (FTIR). The encapsulation efficiencies and release profiles of the essential oils were studied by gas chromatography mass spectrometry (GC-MS) and head-space solid-phase microextraction GC-MS, respectively. Furthermore, the microspheres were tested for antibacterial activity against both Gram-negative and Gram-positive bacterial strains.
The results showed that the microspheres compositions (PLA/PMMA ratio) have significant effect on their characteristics. The process adopted for preparing the microspheres promoted formation of spherical particles at the sizes of 1.5–9.5?µm. The highest encapsulation efficiency of the prepared microspheres was observed in systems consisting of linalool (81.10?±?10.0?wt. % for PLA system and 76.0?±?3.3?wt. % for PMMA system). Confirmation was also made that the release rate of the microspheres was affected by the size of the same. 相似文献
78.
79.
《Journal of vascular and interventional radiology : JVIR》2020,31(2):286-293
PurposeTo evaluate tumor and ablation zone morphology and densitometry related to tumor recurrence in participants with Stage IA non–small cell lung cancer undergoing radiofrequency ablation in a prospective, multicenter trial.Materials and MethodsForty-five participants (median 76 years old; 25 women; 20 men) from 16 sites were followed for 2 years (December 2006 to November 2010) with computed tomography (CT) densitometry. Imaging findings before and after ablation were recorded, including maximum CT attenuation (in Hounsfield units) at precontrast and 45-, 90-, 180-, and 300-s postcontrast.ResultsEvery 1-cm increase in the largest axial diameter of the ablation zone at 3-months’ follow-up compared to the index tumor reduced the odds of 2-year recurrence by 52% (P = .02). A 1-cm difference performed the best (sensitivity, 0.56; specificity, 0.93; positive likelihood ratio of 8). CT densitometry precontrast and at 45 seconds showed significantly different enhancement patterns in a comparison among pretreated lung cancer (delta = +61.2 HU), tumor recurrence (delta = +57 HU), and treated tumor/ablation zone (delta [change in attenuation] = +16.9 HU), (P < .0001). Densitometry from 45 to 300 s was also different among pretreated tumor (delta = −6.8 HU), recurrence (delta = −11.2 HU), and treated tumor (delta = +12.1 HU; P = .01). Untreated and residual tumor demonstrated washout, whereas treated tumor demonstrated increased attenuation.ConclusionsAn ablation zone ≥1 cm larger than the initial tumor, based on 3-month follow-up imaging, is recommended to decrease odds of recurrence. CT densitometry can delineate tumor versus treatment zones. 相似文献
80.