全文获取类型
| 收费全文 | 2544675篇 |
| 免费 | 203260篇 |
| 国内免费 | 22628篇 |
专业分类
| 耳鼻咽喉 | 33765篇 |
| 儿科学 | 80468篇 |
| 妇产科学 | 66991篇 |
| 基础医学 | 350635篇 |
| 口腔科学 | 67339篇 |
| 临床医学 | 238605篇 |
| 内科学 | 501760篇 |
| 皮肤病学 | 55372篇 |
| 神经病学 | 199985篇 |
| 特种医学 | 102433篇 |
| 外国民族医学 | 1021篇 |
| 外科学 | 382434篇 |
| 综合类 | 87807篇 |
| 现状与发展 | 58篇 |
| 一般理论 | 766篇 |
| 预防医学 | 195927篇 |
| 眼科学 | 57447篇 |
| 药学 | 190343篇 |
| 201篇 | |
| 中国医学 | 16465篇 |
| 肿瘤学 | 140741篇 |
出版年
| 2021年 | 26325篇 |
| 2019年 | 23675篇 |
| 2018年 | 31376篇 |
| 2017年 | 25075篇 |
| 2016年 | 27542篇 |
| 2015年 | 33649篇 |
| 2014年 | 45242篇 |
| 2013年 | 60503篇 |
| 2012年 | 80145篇 |
| 2011年 | 86588篇 |
| 2010年 | 52678篇 |
| 2009年 | 48868篇 |
| 2008年 | 76054篇 |
| 2007年 | 80671篇 |
| 2006年 | 81889篇 |
| 2005年 | 79921篇 |
| 2004年 | 73252篇 |
| 2003年 | 71149篇 |
| 2002年 | 67810篇 |
| 2001年 | 116396篇 |
| 2000年 | 120815篇 |
| 1999年 | 102921篇 |
| 1998年 | 31742篇 |
| 1997年 | 28904篇 |
| 1996年 | 29179篇 |
| 1995年 | 28594篇 |
| 1994年 | 26564篇 |
| 1993年 | 24162篇 |
| 1992年 | 81383篇 |
| 1991年 | 79388篇 |
| 1990年 | 76504篇 |
| 1989年 | 72977篇 |
| 1988年 | 67364篇 |
| 1987年 | 66041篇 |
| 1986年 | 61935篇 |
| 1985年 | 59433篇 |
| 1984年 | 45113篇 |
| 1983年 | 37965篇 |
| 1982年 | 23024篇 |
| 1981年 | 20807篇 |
| 1979年 | 40503篇 |
| 1978年 | 28853篇 |
| 1977年 | 24509篇 |
| 1976年 | 22567篇 |
| 1975年 | 23976篇 |
| 1974年 | 28173篇 |
| 1973年 | 27033篇 |
| 1972年 | 24922篇 |
| 1971年 | 22912篇 |
| 1970年 | 21243篇 |
排序方式： 共有10000条查询结果，搜索用时 15 毫秒
21.
María Cabrerizo Gloria Trallero María José Pena Amaia Cilla Gregoria Megias Carmen Mu?oz-Almagro Eva Del Amo Diana Roda Ana Isabel Mensalvas Antonio Moreno-Docón Juan García-Costa Nuria Rabella Manuel Ome?aca María Pilar Romero Sara Sanbonmatsu-Gámez Mercedes Pérez-Ruiz María José Santos-Mu?oz Cristina Calvo And the study group of “Enterovirus parechovirus infections in children under ?years-old Spain” PI- 《European journal of pediatrics》2015,174(11):1511-1516
22.
K.-C. Sung D.-C. Seo S.-J. Lee M.-Y. Lee S.H. Wild C.D. Byrne 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2019,29(5):489-495
Background and aims
It is not known whether non alcoholic fatty liver disease (NAFLD) is a risk factor for diabetes in non obese, non centrally-obese subjects. Our aim was to investigate relationships between fatty liver, insulin resistance and a biomarker score for liver fibrosis with incident diabetes at follow up, in subjects who were neither obese nor centrally-obese.Methods and results
As many as 70,303 subjects with a body mass index (BMI) < 25 kg/m2 and without diabetes were followed up for a maximum of 7.9 years. At baseline, fatty liver was identified by liver ultrasound, insulin resistance (IR) by homeostatic model assessment of insulin resistance (HOMA-IR) ≥2.0, and central obesity by waist circumference (waist circumference ≥90 cm (men) and ≥85 cm (women). The Fibrosis-4 (FIB-4 score) was used to estimate extent of liver fibrosis. Cox proportional hazards models adjusted for confounders were used to estimate hazard ratios (aHRs) for incident diabetes. As many as 852 incident cases of diabetes occurred during follow up (median [IQR] 3.71 [2.03] years). Mean ± SD BMI was 22.8 ± 1.8 and 21.7 ± 2.0 kg/m2 in subjects with and without diabetes at follow up. In subjects without central obesity and with fatty liver, aHRs (95% CI) for incident diabetes at follow up were 2.17 (1.56, 3.03) for men, and 2.86 (1.50,5.46) for women. Similar aHRs for incident diabetes occurred with fatty liver, IR and the highest quartile of FIB-4 combined, in men; and there was a non significant trend toward increased risk in women.Conclusions
In normal weight, non-centrally obese subjects NAFLD is an independent risk factor for incident diabetes. 相似文献23.
J. Rodríguez-Carrio A. Martínez-Zapico I. Cabezas-Rodríguez L. Benavente Á.I. Pérez-Álvarez P. López J.B. Cannata-Andía M. Naves-Díaz A. Suárez 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2019,29(2):135-143
Background and aims
Since accelerated atherosclerosis has been reported in systemic lupus erythematosus (SLE), predictive biomarkers of cardiovascular disease (CVD) are needed. Among non-traditional risk factors, bone mineral density (BMD) has been related to CVD. However, its role in SLE remains controversial. This study aims to analyze the associations of subclinical atherosclerosis with traditional and non-traditional CV risk factors.Methods and results
In a cross-sectional study, atherosclerosis burden was compared between 112 female SLE patients and 31 controls. Plaque number and carotid intima-media wall thickness (cIMT) were assessed by ultrasonography. In a retrospective study, BMD determinations obtained 5-years before the ultrasonography assessment were analyzed in a subgroup of 62 patients. Plaque frequency was increased in SLE, even in patients without CV events or carotid wall thickening. cIMT was increased in patients with CVD, positively correlated with body mass index (BMI). Interestingly, a paradoxical effect of BMI on carotid parameters was observed. Whereas underweight patients (BMI < 20) showed increased prevalence of carotid plaques with low cIMT, those with BMI > 30 showed higher cIMT and plaque burden. Overweight patients (25 < BMI<30) exhibited both elevated cIMT and plaque number. BMI was an independent predictor of BMD. In our retrospective study, patients with either clinical or subclinical CVD exhibited lower BMD levels than their CV-free counterparts. A low lumbar spine BMD independently predicted CVD development after adjusting for confounders.Conclusion
SLE was associated with a higher subclinical atherosclerosis burden, a bimodal effect being observed for BMI. Decreased BMD can be a CV risk biomarker in SLE. 相似文献24.
Anand Dayama Nikolaos Tsilimparis Stephen Kolakowski Nathaniel M. Matolo Misty D. Humphries 《Journal of vascular surgery》2019,69(1):156-163.e1
Background
Chronic limb-threatening ischemia (CLTI), defined as ischemic rest pain or tissue loss secondary to arterial insufficiency, is caused by multilevel arterial disease with frequent, severe infrageniculate disease. The rise in CLTI is in part the result of increasing worldwide prevalence of diabetes, renal insufficiency, and advanced aging of the population. The aim of this study was to compare a bypass-first with an endovascular-first revascularization strategy in patients with CLTI due to infrageniculate arterial disease.Methods
We reviewed the American College of Surgeons National Surgical Quality Improvement Program targeted lower extremity revascularization database from 2012 to 2015 to identify patients with CLTI and isolated infrageniculate arterial disease who underwent primary infrageniculate bypass or endovascular intervention. We excluded patients with a history of ipsilateral revascularization and proximal interventions. The end points were major adverse limb event (MALE), major adverse cardiovascular event (MACE), amputation at 30 days, reintervention, patency, and mortality. Multivariable logistic regression was used to determine the association of a bypass-first or an endovascular-first intervention with outcomes.Results
There were 1355 CLTI patients undergoing first-time revascularization to the infrageniculate arteries (821 endovascular-first revascularizations and 534 bypass-first revascularizations) identified. There was no significant difference in adjusted rate of 30-day MALE in the bypass-first vs endovascular-first revascularization cohort (9% vs 11.2%; odds ratio [OR], 0.73; 95% confidence interval [CI], 0.50-1.08). However, the incidence of transtibial or proximal amputation was lower in the bypass-first cohort (4.3% vs 7.4%; OR, 0.60; CI, 0.36-0.98). Patients with bypass-first revascularization had higher wound complication rates (9.7% vs 3.7%; OR, 2.75; CI, 1.71-4.42) compared with patients in the endovascular-first cohort. Compared with the endovascular-first cohort, the incidence of 30-day MACE was significantly higher in bypass-first patients (6.9% vs 2.6%; adjusted OR, 3.88; CI, 2.18-6.88), and 30-day mortality rates were 3.23% vs 1.8% (adjusted OR, 2.77; CI, 1.26-6.11). There was no difference in 30-day untreated loss of patency, reintervention of treated arterial segment, readmissions, and reoperations between the two cohorts. In subgroup analysis after exclusion of dialysis patients, there was also no significant difference in MALE or amputation between the bypass-first and endovascular-first cohorts.Conclusions
CLTI patients with isolated infrageniculate arterial disease treated by a bypass-first approach have a significantly lower 30-day amputation. However, this benefit was not observed when dialysis patients were excluded. The bypass-first cohort had a higher incidence of MACE compared with an endovascular-first strategy. These results reaffirm the need for randomized controlled trials, such as the Bypass versus Angioplasty in Severe Ischaemia of the Leg (BASIL-2) trial and Best Endovascular vs Best Surgical Therapy in Patients with Critical Limb Ischemia (BEST-CLI), to provide level 1 evidence for the role of endovascular-first vs bypass-first revascularization strategies in the treatment of this population of challenging patients. 相似文献25.
Chunli Liu Wenqing Sun Fenglin Liu Mingxiang Zhou 《The journal of maternal-fetal & neonatal medicine》2019,32(15):2570-2574
Objective: To report a case of labour induction during extracorporeal membrane oxygenation (ECMO) support in a patient with acute respiratory distress syndrome (ARDS) caused by influenza and review of the literature.
Methods: Case report and the literature search of all English articles on delivery while on ECMO in patients with ARDS caused by influenza.
Results: A 25-year-old pregnant woman was initiated with ECMO due to severe ARDS caused by influenza A (H1N1) virus. When the patient had symptoms of colporrhagia and uterine contractions, the medical team decided to start labour induction while on ECMO. There were in total five case reports identified. Maternal oxygenation was improved after delivery and ECMO was successfully discontinued.
Conclusions: Maternal oxygenation was improved after delivery, which may be beneficial to reduce the duration of ECMO. Caesarean section (CS) may be the most used mode and labour induction could be another option. The procedure should be performed by an experienced ECMO team, cooperating with the obstetrician, anaesthesiologist, and ICU doctors. 相似文献
26.
Bernard–Soulier syndrome (BSS) is a rare autosomal recessively inherited bleeding disorder. Pregnancy in patients with BSS is characterized by ante‐, intra‐, or postpartum haemorrhage, which may be delayed and severe. There is no consensus in the management of BSS in pregnancy and so far only 16 pregnancies in nine patients have been described. We report a further three pregnancies in two women with the syndrome. We also outline our management of pregnant patients with BSS. 相似文献
27.
Lalia Y. Ibrahim Krank P. DiFilippo Geremy E. Steed Manuel D. Cerqueira 《Journal of nuclear cardiology》2006,13(6):855-866
Conclusion Several quality-control measures take place before (patient and camera preparation) and during SPECT acquisition to achieve
high-quality images. Not uncommonly, technologists and physicians are left with suboptimal images that have to be addressed
to reach the “right answer” for patient diagnosis and hence management. In many cases patients may be reimaged, especially
if the problem is detected early, but in other cases either the patient has left the nuclear laboratory or there is an inevitable
problem that, even with reimaging, will not be resolved. In these situations the technologist and physician have to seek the
available techniques to obtain the best images possible. These resources are discussed in this issue as an aid in quality
control to obtain the best possible images. 相似文献
28.
29.
D B Irving J L Cook H B Menz 《Journal of Science and Medicine in Sport》2006,9(1-2):11-22; discussion 23-4
30.