全文获取类型
收费全文 | 23190篇 |
免费 | 1574篇 |
国内免费 | 155篇 |
专业分类
耳鼻咽喉 | 258篇 |
儿科学 | 526篇 |
妇产科学 | 433篇 |
基础医学 | 2743篇 |
口腔科学 | 945篇 |
临床医学 | 1971篇 |
内科学 | 4878篇 |
皮肤病学 | 505篇 |
神经病学 | 1471篇 |
特种医学 | 663篇 |
外国民族医学 | 5篇 |
外科学 | 3342篇 |
综合类 | 543篇 |
一般理论 | 17篇 |
预防医学 | 1822篇 |
眼科学 | 951篇 |
药学 | 2210篇 |
中国医学 | 241篇 |
肿瘤学 | 1395篇 |
出版年
2023年 | 276篇 |
2022年 | 265篇 |
2021年 | 1200篇 |
2020年 | 869篇 |
2019年 | 1060篇 |
2018年 | 1284篇 |
2017年 | 894篇 |
2016年 | 970篇 |
2015年 | 994篇 |
2014年 | 1352篇 |
2013年 | 1579篇 |
2012年 | 2133篇 |
2011年 | 2188篇 |
2010年 | 1275篇 |
2009年 | 975篇 |
2008年 | 1447篇 |
2007年 | 1308篇 |
2006年 | 1096篇 |
2005年 | 922篇 |
2004年 | 725篇 |
2003年 | 631篇 |
2002年 | 541篇 |
2001年 | 77篇 |
2000年 | 80篇 |
1999年 | 89篇 |
1998年 | 73篇 |
1997年 | 57篇 |
1996年 | 48篇 |
1995年 | 48篇 |
1994年 | 30篇 |
1993年 | 45篇 |
1992年 | 27篇 |
1991年 | 26篇 |
1990年 | 23篇 |
1989年 | 31篇 |
1988年 | 28篇 |
1987年 | 14篇 |
1986年 | 15篇 |
1985年 | 17篇 |
1984年 | 22篇 |
1983年 | 18篇 |
1982年 | 23篇 |
1981年 | 15篇 |
1980年 | 14篇 |
1979年 | 17篇 |
1978年 | 15篇 |
1977年 | 9篇 |
1976年 | 17篇 |
1975年 | 11篇 |
1974年 | 14篇 |
排序方式: 共有10000条查询结果,搜索用时 171 毫秒
1.
2.
3.
4.
Aaron Pitzele Mohammad Rahimi Eric Armbrecht 《The journal of maternal-fetal & neonatal medicine》2015,28(15):1770-1773
Objective: To determine whether packed red blood cell (PRBC) transfusion affects post-prandial superior mesenteric artery blood flow velocities (SMA BFVs) in very-low birth weight (VLBW) neonates and if so, at what time point after transfusion restoration of previous SMA BFV patterns occurs.Design/Methods: VLBW pre-term neonates, older than 14 days and tolerating bolus enteral feedings administered every 3?h were enrolled in this prospective observational study. Pulsed Doppler ultrasound was used to measure pre- and post-prandial (at 45?min) time-averaged mean, peak and end diastolic velocities (TAMV, PSV, EDV) immediately before and after 15?ml/kg of PRBC transfusion was given over 3?h; patent ductus arteriosus (PDA) status was also evaluated. Subsequent pre- and post-prandial SMA BFVs were recorded 24 and 48?h after the transfusion.Results: Pre- and post-prandial measurements were obtained for 21 out of 25 enrolled infants. Post-prandial SMA BFVs were attenuated during the feedings immediately after transfusion; at 24 and 48?h after transfusion, changes in post-prandial SMA BFVs were similar to those measured prior to transfusion; the presence of the PDA did not affect results.Conclusions: PRBC transfusion blunted SMA BFV responses to feedings immediately after the transfusion with normalization observed 24?h post-transfusion. 相似文献
5.
Ahmed M. Abu El-Asrar Ajmal Ahmad Eef Allegaert Mohammad Mairaj Siddiquei Priscilla W. Gikandi Gert De Hertogh 《Ocular immunology and inflammation》2020,28(4):575-588
ABSTRACT
Purpose
To investigate the expression of IL-11 and its receptor IL-11Rα and to quantify density of CD163+ M2 macrophages in proliferative diabetic retinopathy (PDR). 相似文献6.
Nonalcoholic fatty liver disease (NAFLD) is a major cause of liver‐related morbidity; its prevalence is elevating due to the rising epidemic of obesity. Several clinical trials have examined the effects of curcumin supplementation on anthropometric variables in NAFLD patients with inconclusive results. This dose–response meta‐analysis aimed to evaluate the impact of curcumin supplementation on body mass index (BMI), body weight, and waist circumference (WC) in patients with NAFLD. A systematic review of the literature was conducted using PubMed/Medline, ISI Web of Science, Scopus, Cochrane Library, EMBASE, Google Scholar, Sid.ir, and Magiran.com to identify eligible studies up to March 2019. A meta‐analysis of eligible studies was performed using the random‐effects model to estimate the pooled effect size. Eight randomized controlled trials with 520 participants (curcumin group = 265 and placebo group = 255) were included. Supplementation dose and duration ranged from 70 to 3,000 mg/day and 8 to 12 weeks, respectively. Curcumin supplementation significantly reduced BMI (weighted mean difference [WMD] = ?0.34 kg/m2, 95% CI [?0.64, ?0.04], p < .05) and WC (WMD = ?2.12 cm, 95% CI [?3.26, ?0.98], p < .001). However, no significant effects of curcumin supplementation on body weight were found. These results suggest that curcumin supplementation might have a positive effect on visceral fat and abdominal obesity that have been associated with NAFLD. 相似文献
7.
8.
9.
Moises Rodriguez-Gonzalez Antonio Moruno Tirado Reza Hosseinpour Jose Santos de Soto 《Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital》2015,42(4):350-356
Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) is a rare congenital condition. It responds well to early diagnosis and treatment, but otherwise the prognosis is poor. We present our case series of 12 patients (mean age, 2 ± 2.58 yr; age range, 2 mo–8 yr), emphasizing the diagnostic process and discussing our surgical results. The diagnosis of ALCAPA should be suspected in infants who have dilated cardiomyopathy with electrocardiographic changes that suggest ischemia, and in older children who have isolated mitral regurgitation. When clinical suspicion is high, the results of 2-dimensional echocardiography combined with color-flow Doppler studies in expert hands can establish the diagnosis, thus avoiding angiography in critically ill infants. The treatment of choice in our patients was transfer and reimplantation of the left coronary artery onto the ascending aorta. There were 2 deaths: both were infants in extremis who underwent emergency surgery. An older child with severe ventricular dysfunction was given mechanical ventricular assistance and then heart transplantation. As of this report, all 10 survivors remained well and asymptomatic. 相似文献
10.