全文获取类型
收费全文 | 2278篇 |
免费 | 102篇 |
国内免费 | 11篇 |
专业分类
耳鼻咽喉 | 8篇 |
儿科学 | 114篇 |
妇产科学 | 71篇 |
基础医学 | 344篇 |
口腔科学 | 53篇 |
临床医学 | 206篇 |
内科学 | 530篇 |
皮肤病学 | 40篇 |
神经病学 | 139篇 |
特种医学 | 52篇 |
外科学 | 155篇 |
综合类 | 76篇 |
一般理论 | 3篇 |
预防医学 | 154篇 |
眼科学 | 45篇 |
药学 | 229篇 |
1篇 | |
中国医学 | 26篇 |
肿瘤学 | 145篇 |
出版年
2023年 | 10篇 |
2022年 | 36篇 |
2021年 | 62篇 |
2020年 | 40篇 |
2019年 | 60篇 |
2018年 | 78篇 |
2017年 | 36篇 |
2016年 | 60篇 |
2015年 | 54篇 |
2014年 | 76篇 |
2013年 | 106篇 |
2012年 | 156篇 |
2011年 | 167篇 |
2010年 | 96篇 |
2009年 | 57篇 |
2008年 | 133篇 |
2007年 | 133篇 |
2006年 | 113篇 |
2005年 | 114篇 |
2004年 | 98篇 |
2003年 | 99篇 |
2002年 | 69篇 |
2001年 | 47篇 |
2000年 | 61篇 |
1999年 | 37篇 |
1998年 | 11篇 |
1997年 | 13篇 |
1996年 | 10篇 |
1995年 | 12篇 |
1994年 | 11篇 |
1993年 | 10篇 |
1992年 | 25篇 |
1991年 | 20篇 |
1990年 | 21篇 |
1989年 | 18篇 |
1988年 | 9篇 |
1987年 | 20篇 |
1986年 | 18篇 |
1985年 | 17篇 |
1984年 | 15篇 |
1983年 | 9篇 |
1979年 | 8篇 |
1977年 | 11篇 |
1976年 | 12篇 |
1974年 | 11篇 |
1973年 | 13篇 |
1972年 | 12篇 |
1971年 | 8篇 |
1970年 | 13篇 |
1969年 | 13篇 |
排序方式: 共有2391条查询结果,搜索用时 421 毫秒
81.
82.
83.
Less invasive surfactant administration methods without laryngoscopy and endotracheal catheterization include delivery via laryngeal mask airway, pharyngeal instillation, and aerosolization. These less invasive techniques are promising and have several advantages over INSURE (Intubation-Surfactant-Extubation) and thin catheter techniques. The objective of this review is to discuss the requisites, techniques, short-term outcomes, and adverse events associated with these methods. 相似文献
84.
Balakrishnan V Unnikrishnan AG Thomas V Choudhuri G Veeraraju P Singh SP Garg P Pai CG Devi RN Bhasin D Jayanthi V Premalatha N Chacko A Kar P Rai RR Rajan R Subhalal N Mehta R Mishra SP Dwivedi M Vinayakumar KR Jain AK Biswas K Mathai S Varghese J Ramesh H Alexander T Philip J Raj VV Vinodkumar A Mukevar S Sawant P Nair P Kumar H Sudhindran S Dhar P Sudheer OV Sundaram KR Tantri BV Singh D Nath TR 《JOP : Journal of the pancreas》2008,9(5):593-600
85.
Outcome after surgical resection of intraductal papillary and mucinous tumors of the pancreas 总被引:19,自引:0,他引:19
Cuillerier E Cellier C Palazzo L Devière J Wind P Rickaert F Cugnenc PH Cremer M Barbier JP 《The American journal of gastroenterology》2000,95(2):441-445
OBJECTIVE: Treatment of intraductal papillary and mucinous tumors of pancreas (IPMT) usually requires surgery. The objective of this study was to evaluate the risk of recurrence in patients after surgery according to the histological nature of the neoplasm and the type of surgery. METHODS: The outcome of 45 patients who underwent partial pancreatectomy (n = 35) or total pancreatectomy (n = 10) for IPMT was studied according to the nature of the neoplasm (invasive carcinoma or noninvasive neoplasm), type of surgery (partial or total pancreatectomy), and lymph nodes status. RESULTS: The overall 3-yr actuarial survival rate was 83%. Death occurred in seven of 20 (35%) patients with invasive carcinoma and in one of 26 (4%) patients with noninvasive tumors (p<0.05). There were two recurrences in the seven patients with noninvasive neoplasm who underwent partial pancreatectomy with involved resection margins, and none in the 13 patients with disease-free margins. In patients with invasive carcinoma, there was one recurrence after total pancreatectomy, six after partial pancreatectomy with disease-free margins and six after partial pancreatectomy with involved margins. In patients with invasive carcinoma, total pancreatectomy and the absence of lymph nodes involvement were independently associated with a low risk of recurrence. CONCLUSIONS: IPMT may be managed as follows: 1) in patients with noninvasive neoplasms, partial pancreatic resection should be guided by frozen section examination until disease-free margins are obtained; and 2) in patients with invasive carcinoma, total pancreatectomy seems most likely to cure the patient, but should be discussed according to the general status and the age. 相似文献
86.
Various musculoskeletal injuries are well known complications of epilepsy either because of direct trauma or because of unbalanced forceful muscle contraction. We report a case of non-traumatic bilateral central acetabular fracture dislocation due to seizure activity induced by neurocysticercosis of the brain, which was managed conservatively and obtained reasonable good outcome. This case highlights the importance of proper evaluation in young non-osteoporotic patients who have experienced an epileptic attack without any previous history. It is also imperative to mention that these patients should be thoroughly examined neurologically to find out the exact etiology and should be treated accordingly to prevent future seizure activity. 相似文献
87.
Prolactin (PRL) is a polypeptide hormone with a wide range of physiological functions, and is critical for female reproduction. PRL exerts its action by binding to membrane bound receptor isoforms broadly classified as the long form and the short form receptors. Both receptor isoforms are highly expressed in the ovary as well as in the uterus. Although signaling through the long form is believed to be more predominant, it remains unclear whether activation of this isoform alone is sufficient to support reproductive functions or whether both types of receptor are required. The generation of transgenic mice selectively expressing either the short or the long form of PRL receptor has provided insight into the differential signaling mechanisms and physiological functions of these receptors. This review describes the essential finding that both long and short receptor isoforms are crucial for ovarian functions and female fertility, and highlights novel mechanisms of action for these receptors. 相似文献
88.
Lisa G. Suter MD Shu-Xia Li PhD Jacqueline N. Grady MS Zhenqiu Lin PhD Yongfei Wang MS Kanchana R. Bhat MPH Dima Turkmani DrPH MBA Steven B. Spivack MPH Peter K. Lindenauer MD MSc Angela R. Merrill PhD Elizabeth E. Drye MD SM Harlan M. Krumholz MD SM Susannah M. Bernheim MD MHS 《Journal of general internal medicine》2014,29(10):1333-1340
BACKGROUND
The Centers for Medicare & Medicaid Services publicly reports risk-standardized mortality rates (RSMRs) within 30-days of admission and, in 2013, risk-standardized unplanned readmission rates (RSRRs) within 30-days of discharge for patients hospitalized with acute myocardial infarction (AMI), heart failure (HF), and pneumonia. Current publicly reported data do not focus on variation in national results or annual changes.OBJECTIVE
Describe U.S. hospital performance on AMI, HF, and pneumonia mortality and updated readmission measures to provide perspective on national performance variation.DESIGN
To identify recent changes and variation in national hospital-level mortality and readmission for AMI, HF, and pneumonia, we performed cross-sectional panel analyses of national hospital performance on publicly reported measures.PARTICIPANTS
Fee-for-service Medicare and Veterans Health Administration beneficiaries, 65 years or older, hospitalized with principal discharge diagnoses of AMI, HF, or pneumonia between July 2009 and June 2012. RSMRs/RSRRs were calculated using hierarchical logistic models risk-adjusted for age, sex, comorbidities, and patients’ clustering among hospitals.Results
Median (range) RSMRs for AMI, HF, and pneumonia were 15.1% (9.4–21.0%), 11.3% (6.4–17.9%), and 11.4% (6.5–24.5%), respectively. Median (range) RSRRs for AMI, HF, and pneumonia were 18.2% (14.4–24.3%), 22.9% (17.1–30.7%), and 17.5% (13.6–24.0%), respectively. Median RSMRs declined for AMI (15.5% in 2009–2010, 15.4% in 2010–2011, 14.7% in 2011–2012) and remained similar for HF (11.5% in 2009–2010, 11.9% in 2010–2011, 11.7% in 2011–2012) and pneumonia (11.8% in 2009–2010, 11.9% in 2010–2011, 11.6% in 2011–2012). Median hospital-level RSRRs declined: AMI (18.5% in 2009–2010, 18.5% in 2010–2011, 17.7% in 2011–2012), HF (23.3% in 2009–2010, 23.1% in 2010–2011, 22.5% in 2011–2012), and pneumonia (17.7% in 2009–2010, 17.6% in 2010–2011, 17.3% in 2011–2012).Conclusions
We report the first national unplanned readmission results demonstrating declining rates for all three conditions between 2009–2012. Simultaneously, AMI mortality continued to decline, pneumonia mortality was stable, and HF mortality experienced a small increase. 相似文献89.
Malvastrum coromandelianum L. (Garcke) is extensively used in traditional medicinal systems to treat various ailments. In the present study, an alkali-soluble polysaccharide (MAP) was isolated from the leaves of M. coromandelianum in 1.15% (w/w) yield. MAP was composed of l-rhamnose, l-arabinose, d-xylose, d-glucose and d-galactose in a 1.00 : 6.04 : 19.88 : 1.07 : 3.03 molar ratio along with d-glucuronic acid (1.95). Methylation/linkage analysis revealed a backbone of →4)-β-d-Xylp(1→ (30.09 mol%) with a side chain of →3)-α-l-Araf(1→ (15.21 mol%) residues. The structure of MAP was elucidated by a combination of degradative and derivatization techniques, including hydrolysis, alditol acetate derivatization, methylation, GC-MS, partial hydrolysis, ESI-MS and NMR (1D, 2D) spectral analysis. Based on correlation analysis, MAP was found to be an arabinoxylan comprising a backbone of →4)-β-d-linked Xylp(1→ with branching at O-2 by a →3)-α-l-Araf(1→ and →3)-β-d-Xylp(1→ chain. MAP also exhibited ferric ion reducing activity, with a reducing power of 0.914 ± 0.01 (R2 = 0.972) at 1 mg mL−1 concentration, which showed dose-dependent behavior. MAP can be utilized as a potential antioxidant.The structure of MAP was studied by degradative, derivatization and spectroscopic methods, and it was found to be an arabinoxylan comprising a backbone of →4)-β-d-linked Xylp(1→ with branching at O-2 by →3)-α-l-Araf(1→ and →3)-β-d-Xylp(1→ chains. 相似文献
90.
Sathish Paramasivan Ahmed Bassiouni Arron Shiffer Matthew R. Dillon Emily K. Cope Clare Cooksley Mahnaz Ramezanpour Sophia Moraitis Mohammad Javed Ali Benjamin Bleier Claudio Callejas Marjolein E. Cornet Richard G. Douglas Daniel Dutra Christos Georgalas Richard J. Harvey Peter H. Hwang Amber U. Luong Rodney J. Schlosser Pongsakorn Tantilipikorn Marc A. Tewfik Sarah Vreugde Peter-John Wormald J. Gregory Caporaso Alkis J. Psaltis 《Allergy》2020,75(8):2037-2049
The sinonasal microbiome remains poorly defined, with our current knowledge based on a few cohort studies whose findings are inconsistent. Furthermore, the variability of the sinus microbiome across geographical divides remains unexplored. We characterize the sinonasal microbiome and its geographical variations in both health and disease using 16S rRNA gene sequencing of 410 individuals from across the world. Although the sinus microbial ecology is highly variable between individuals, we identify a core microbiome comprised of Corynebacterium, Staphylococcus, Streptococcus, Haemophilus and Moraxella species in both healthy and chronic rhinosinusitis (CRS) cohorts. Corynebacterium (mean relative abundance = 44.02%) and Staphylococcus (mean relative abundance = 27.34%) appear particularly dominant in the majority of patients sampled. Amongst patients suffering from CRS with nasal polyps, a statistically significant reduction in relative abundance of Corynebacterium (40.29% vs 50.43%; P = .02) was identified. Despite some measured differences in microbiome composition and diversity between some of the participating centres in our cohort, these differences would not alter the general pattern of core organisms described. Nevertheless, atypical or unusual organisms reported in short-read amplicon sequencing studies and that are not part of the core microbiome should be interpreted with caution. The delineation of the sinonasal microbiome and standardized methodology described within our study will enable further characterization and translational application of the sinus microbiota. 相似文献