全文获取类型
收费全文 | 13832篇 |
免费 | 660篇 |
国内免费 | 122篇 |
专业分类
耳鼻咽喉 | 343篇 |
儿科学 | 653篇 |
妇产科学 | 566篇 |
基础医学 | 1019篇 |
口腔科学 | 454篇 |
临床医学 | 1121篇 |
内科学 | 3509篇 |
皮肤病学 | 211篇 |
神经病学 | 831篇 |
特种医学 | 598篇 |
外科学 | 3256篇 |
综合类 | 189篇 |
一般理论 | 1篇 |
预防医学 | 320篇 |
眼科学 | 487篇 |
药学 | 533篇 |
中国医学 | 29篇 |
肿瘤学 | 494篇 |
出版年
2024年 | 11篇 |
2023年 | 113篇 |
2022年 | 215篇 |
2021年 | 399篇 |
2020年 | 252篇 |
2019年 | 317篇 |
2018年 | 402篇 |
2017年 | 333篇 |
2016年 | 548篇 |
2015年 | 636篇 |
2014年 | 695篇 |
2013年 | 829篇 |
2012年 | 1093篇 |
2011年 | 977篇 |
2010年 | 608篇 |
2009年 | 532篇 |
2008年 | 951篇 |
2007年 | 1099篇 |
2006年 | 1028篇 |
2005年 | 994篇 |
2004年 | 882篇 |
2003年 | 657篇 |
2002年 | 581篇 |
2001年 | 91篇 |
2000年 | 55篇 |
1999年 | 56篇 |
1998年 | 57篇 |
1997年 | 44篇 |
1996年 | 29篇 |
1995年 | 26篇 |
1994年 | 15篇 |
1993年 | 7篇 |
1992年 | 15篇 |
1991年 | 11篇 |
1990年 | 11篇 |
1989年 | 15篇 |
1988年 | 3篇 |
1986年 | 3篇 |
1985年 | 6篇 |
1984年 | 2篇 |
1982年 | 1篇 |
1981年 | 3篇 |
1980年 | 1篇 |
1979年 | 2篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1975年 | 2篇 |
1974年 | 1篇 |
1973年 | 2篇 |
1970年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
81.
82.
Nilüfer Aylin Acet
ztürk Asli G. Dilektasli
zge AydnGülü Ezgi Demirden Funda Cokun Ahmet Ursava Mehmet Karada Esra Uzaslan 《The clinical respiratory journal》2022,16(1):49
IntroductionEosinophilic airway inflammation is a recognized inflammatory pattern in subgroups of patients with chronic obstructive pulmonary disease (COPD). However, there are still conflicting results between various studies concerning the effect of eosinophils in COPD patients. Our aim with this study was to evaluate eosinophilic inflammation and its relation to the clinical characteristics in a group of COPD patients.MethodsStable COPD patients with FEV1% predicted < 50 or with ≥ 1 exacerbation leading to hospital admission or ≥2 moderate or severe exacerbation history were consecutively enrolled from outpatient clinics.ResultsWe included 90 male COPD patients, with a mean age of 63.3 ± 9.2. Mean FEV1% predicted was 35.9 ± 11.3. Eosinophilic inflammation (eosinophil percentage ≥2%) was evident in 54 (60%) of the patients. Participants with eosinophilic inflammation were significantly older and had better FEV1 predicted % values. Eosinophilic COPD patients were characterized with better quality of life and fewer symptoms. COPD patients with noneosinophilic inflammation used supplemental long‐term oxygen therapy (LTOT) more frequently compared to patients with eosinophilic inflammation (36.1% vs. 14.8%, p = 0.01). Eosinophilic inflammation is associated with less dyspnea severity measured by mMRC (OR: 0.542 95% CI: 0.342–0.859, p = 0.009) and less LTOT use (OR: 0.334 95% CI: 0.115–0.968, p = 0.04) regardless of age, severity of airflow limitation, and having frequent exacerbation phenotype.ConclusionOur study supports the growing evidence for a potential role of eosinophilic inflammation phenotype in COPD with distinctive clinical characteristics. Eosinophilic inflammation is inversely associated with dyspnea severity measured by mMRC and LTOT use independently from age, total number of exacerbations, St. George Respiratory Questionnaire (SGRQ) total score and FEV1% predicted. 相似文献
83.
目的 探讨血清胱抑素(Cyst-C)、尿微量白蛋白/肌酐(UmAlb/UCr)对高血压患者早期肾损害的诊断价值.方法 根据肾动态显像结果将85例原发性高血压患者分为早期肾功能损害组(A组)32例和单纯高血压组(B组)53例,并选取健康体检者50例为对照组,采用酶联免疫法测定各组Cyst-C、UmAlb/UCr、血清尿素氮(BUN)、血清肌酐(Scr)含量.结果 与对照组相比,A组及B组Cyst-C、UmAlb/UCr水平显著升高,B组则高于A组,差异有统计学意义(P<0.05),而三组BUN、Scr水平比较差异无统计学意义(P>0.05).随着高血压分级的增加,Cyst-C、UmAlb/UCr水平显著上升,其中Ⅲ级组患者显著高于Ⅰ级组及Ⅱ级组,差异有统计学意义(P.<0.05).Cyst-C灵敏性、特异性、准确性分别为81.6%、82.3%、69.2%,UmAlb/UCr灵敏性、特异性、准确性分别为84.5%、83.4%、76.9%,而UmAlb/UCr+Cyst-C灵敏性、特异性、准确性分别为93.2%、91.3%、92.3%.B组Cyst-C与UmAlb/UC联合检测阳性率显著高于单纯UmAlb/UCr或Cyst-C检测,差异有统计学意义(P<0.05).结论 Cyst-C与UmAlb/UC联合检测有助于高血压患者早期肾损害的诊断. 相似文献
84.
85.
Sait Demirkol M.D. Ugur Kucuk M.D. Oben Baysan M.D. Sevket Balta M.D. Turgay Celik M.D. Ibrahim Halil Kurt M.D. Hilal Olgun Kucuk M.D. Uygar Cagdas Yuksel M.D. Murat Unlu M.D. Mehmet Yokusoglu M.D. 《Echocardiography (Mount Kisco, N.Y.)》2012,29(9):1064-1070
Aims: The aim of this study is to investigate the effect of mitral stenosis (MS) on left atrial (LA) function using two‐dimensional speckle tracking echocardiography (2DSTE). Methods and Results: The study subjects consisted of 52 patients with asymptomatic MS and 52 control subjects. LA function was assessed using prototype speckle tracking software and manual tracking method. Maximal LA volume (LAVmax) and minimal LA volume (LAVmin) and LA volume before atrial contraction (LAVpre‐a) were measured. Using these volumes, LA reservoir, conduit and booster pump fuction parameters were calculated. Indexed LAVmax, LAVmin, and LAVpre‐a measurements via speckle tracking were highly correlated with manual tracing methods in both groups. Expansion index (67.8 ± 36.4 vs. 148.3 ± 44.2), diastolic emptying index (37.7 ± 12.9 vs. 58.0 ± 8.5), passive emptying (37.3 ± 14.1 vs. 70.4 ± 10.4) and passive emptying index (13.3 ± 6.3 vs. 41.3 ± 10.6) were decreased significantly in MS patients (P < 0.001). In contrast active emptying index (62.6 ± 4.1 vs. 29.5 ± 10.1) increased in MS group (P < 0.001) while active emptying (28.1 ± 13.0 vs. 28.3 ± 6.9) remained same among both groups. Conclusions: This is the first study relating LA volumes and function assessed by 2DSTE to MS. 2D speckle tracking analysis of LA volume is relatively easy and provides more detailed information regarding the changes in LA volumes during the cardiac cycle. 相似文献
86.
87.
Cengiz Sarikurkcu Mehmet Halil Solak Serap Cetinkaya 《Ecology of food and nutrition》2013,52(4):346-363
In the present study, the contents of Zn, Fe, Cu, Mn, Co, Ni, Pb, Cd, Cr, Al, Ca, Mg, and K in Agaricus campestris, Agrocybe cylindracea, Collybia dryophila, Helvella leucopus, Russula delica, Tricholoma auratum, Amanita ovoidea, Melanoleuca excissa, Rhizopogon roseolus, Russula chloroides, Volvoriella gloiocephala, Lyophyllum decastes, Morcella angusticeps, Morchella esculenta and Morcella eximia collected from Isparta, Mugla, and Osmaniye provinces (Turkey) were determined by inductively coupled plasma optical emission spectrometry (ICP-OES) after microwave digestion. The intake of heavy metals (Pb, Cd) and other metals (Fe, Cu, Zn) by consumption of 30 g dry weight of mushrooms daily poses no risk at all except in A. cylindracea and H. leucopus (for Cd) for the consumer. 相似文献
88.
89.