全文获取类型
收费全文 | 29995篇 |
免费 | 2354篇 |
国内免费 | 112篇 |
专业分类
耳鼻咽喉 | 361篇 |
儿科学 | 972篇 |
妇产科学 | 616篇 |
基础医学 | 3675篇 |
口腔科学 | 907篇 |
临床医学 | 3128篇 |
内科学 | 5678篇 |
皮肤病学 | 419篇 |
神经病学 | 3008篇 |
特种医学 | 1187篇 |
外科学 | 4674篇 |
综合类 | 442篇 |
一般理论 | 27篇 |
预防医学 | 2764篇 |
眼科学 | 632篇 |
药学 | 2246篇 |
中国医学 | 23篇 |
肿瘤学 | 1702篇 |
出版年
2023年 | 126篇 |
2022年 | 213篇 |
2021年 | 602篇 |
2020年 | 365篇 |
2019年 | 596篇 |
2018年 | 674篇 |
2017年 | 493篇 |
2016年 | 519篇 |
2015年 | 609篇 |
2014年 | 921篇 |
2013年 | 1270篇 |
2012年 | 1904篇 |
2011年 | 1908篇 |
2010年 | 1064篇 |
2009年 | 1043篇 |
2008年 | 1791篇 |
2007年 | 1876篇 |
2006年 | 1855篇 |
2005年 | 1844篇 |
2004年 | 1716篇 |
2003年 | 1521篇 |
2002年 | 1428篇 |
2001年 | 513篇 |
2000年 | 522篇 |
1999年 | 528篇 |
1998年 | 357篇 |
1997年 | 274篇 |
1996年 | 257篇 |
1995年 | 246篇 |
1994年 | 217篇 |
1993年 | 214篇 |
1992年 | 338篇 |
1991年 | 321篇 |
1990年 | 295篇 |
1989年 | 250篇 |
1988年 | 277篇 |
1987年 | 258篇 |
1986年 | 264篇 |
1985年 | 242篇 |
1984年 | 240篇 |
1983年 | 200篇 |
1982年 | 166篇 |
1981年 | 154篇 |
1980年 | 139篇 |
1979年 | 175篇 |
1978年 | 149篇 |
1975年 | 123篇 |
1974年 | 119篇 |
1973年 | 120篇 |
1972年 | 111篇 |
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
1.
2.
Well‐being,health and fitness of children who use wheelchairs: Feasibility study protocol to develop child‐centred ‘keep‐fit’ exercise interventions
下载免费PDF全文
![点击此处可从《Journal of advanced nursing》网站下载免费的PDF全文](/ch/ext_images/free.gif)
3.
4.
Catherine L. Omosule Dominique Joseph Brooke Weiler Victoria L. Gremminger Spencer Silvey Youngjae Jeong Ashique Rafique Pamela Krueger Sandra Kleiner Charlotte L. Phillips 《Journal of bone and mineral research》2022,37(5):938-953
Osteogenesis imperfecta (OI) is a collagen-related bone disorder characterized by fragile osteopenic bone and muscle weakness. We have previously shown that the soluble activin receptor type IIB decoy (sActRIIB) molecule increases muscle mass and improves bone strength in the mild to moderate G610C mouse model of OI. The sActRIIB molecule binds multiple transforming growth factor-β (TGF-β) ligands, including myostatin and activin A. Here, we investigate the musculoskeletal effects of inhibiting activin A alone, myostatin alone, or both myostatin and activin A in wild-type (Wt) and heterozygous G610C (+/G610C) mice using specific monoclonal antibodies. Male and female Wt and +/G610C mice were treated twice weekly with intraperitoneal injections of monoclonal control antibody (Ctrl-Ab, Regn1945), anti-activin A antibody (ActA-Ab, Regn2476), anti-myostatin antibody (Mstn-Ab, Regn647), or both ActA-Ab and Mstn-Ab (Combo, Regn2476, and Regn647) from 5 to 16 weeks of age. Prior to euthanasia, whole body composition, metabolism and muscle force generation assessments were performed. Post euthanasia, hindlimb muscles were evaluated for mass, and femurs were evaluated for changes in microarchitecture and biomechanical strength using micro–computed tomography (μCT) and three-point bend analyses. ActA-Ab treatment minimally impacted the +/G610C musculoskeleton, and was detrimental to bone strength in male +/G610C mice. Mstn-Ab treatment, as previously reported, resulted in substantial increases in hindlimb muscle weights and overall body weights in Wt and male +/G610C mice, but had minimal skeletal impact in +/G610C mice. Conversely, the Combo treatment outperformed ActA-Ab alone or Mstn-Ab alone, consistently increasing hindlimb muscle and body weights regardless of sex or genotype and improving bone microarchitecture and strength in both male and female +/G610C and Wt mice. Combinatorial inhibition of activin A and myostatin more potently increased muscle mass and bone microarchitecture and strength than either antibody alone, recapturing most of the observed benefits of sActRIIB treatment in +/G610C mice. © 2022 American Society for Bone and Mineral Research (ASBMR). 相似文献
5.
Lee Mi Jung Romero Sergio Velozo Craig A. Gruber-Baldini Ann L. Shulman Lisa M. 《Quality of life research》2019,28(6):1595-1603
Quality of Life Research - This study investigated the PROMIS Self-Efficacy Measure for Managing Chronic Conditions (PROMIS-SE) domain distributions and examined the factor structure of the... 相似文献
6.
Interaction effects between the 5‐hydroxy tryptamine transporter‐linked polymorphic region (5‐HTTLPR) genotype and family conflict on adolescent alcohol use and misuse
下载免费PDF全文
![点击此处可从《Addiction (Abingdon, England)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
7.
8.
Reem Haj-Ali BDS DDS MS ; Mary Walker DDS PhD ; Karen Williams PhD ; Yong Wang PhD ; Paulette Spencer DDS PhD 《Journal of prosthodontics》2006,15(2):82-88
PURPOSE: The purpose of this study was to compare the dentin/adhesive interfacial characteristics when bonding to noncarious as well as caries-affected dentin. MATERIALS AND METHODS: Seven extracted, unerupted, third molars were sectioned into halves. Artificial caries was created on one-half of each tooth, leaving the other half as a control. Dentin surfaces were treated with UNO adhesive according to the manufacturer's instructions for the wet-bonding technique and under environmental conditions present in the oral cavity. Dentin/adhesive interface sections of each half-tooth were stained with Goldner's trichrome, a classic bone stain, and examined using light microscopy. The width of exposed collagen was measured directly from photomicrographs, and adhesive penetration was analyzed qualitatively. RESULTS: The degree and extent to which the adhesive encapsulated the demineralized dentin matrix were reflected in the color difference in the stained sections with the noncarious dentin sections showing a degree of collagen encapsulation superior to that of the caries-affected dentin sections. The overall mean widths of exposed collagen were significantly (p < or = .05) greater at the caries-affected dentin/adhesive interface, 8.6 (1.7) microm, as compared with those at the noncarious dentin/adhesive interface, 6.0 (1.5) microm. CONCLUSIONS: The morphologic characteristics of the caries-affected dentin/interface suggest an increase in the exposed collagen zone and a decrease in the quality of the adhesive infiltration when compared with noncarious dentin. The evidence suggests that dentin substrate characteristics have a significant effect on the dentin/adhesive interface structure. 相似文献
9.
Joseph Biederman Haitao Gao Ann K Rogers Thomas J Spencer 《Neuropsychopharmacology》2006,60(10):1106-1110
BACKGROUND: The validity of parent reports regarding children's attention-deficit/hyperactivity disorder (ADHD) symptoms has been questioned. This study assessed whether parent reports were as sensitive as teacher reports to document change in ADHD symptoms during clinical trials with atomoxetine. METHODS: Data were compared from two randomized, double-blind, placebo-controlled clinical trials of atomoxetine using different versions (parent or teacher) of the same rating scale (Attention-Deficit/Hyperactivity Disorder Rating Scale-IV [parent or teacher] Version: Investigator Administered and Scored - ADHD RS). Exclusion criteria included history of bipolar disorder, psychosis, seizures, alcohol abuse, or positive drug screen. Patients (6-16 years old) were treated with atomoxetine (titrated to a maximum dose of 1.8 mg/kg/day) administered once daily for up to 7 weeks. Parent and teacher ratings were compared using an analysis of covariance (ANCOVA) model. RESULTS: The analysis (n = 318) showed that treatment effects (mean change, baseline to endpoint) were similar between parent and teacher ratings (total, p = .762; inattention, p = .519; hyperactive/impulsive, p = .955). Effect sizes also were similar based on total scores (parent ratings = .69; teacher ratings = .63). CONCLUSIONS: Parent reports are as sensitive as teacher reports in assessing the efficacy of long-acting pharmacologic treatment for ADHD in children during clinical trials using the nonstimulant atomoxetine. 相似文献
10.
Despite numerous studies of approach- and avoidant mindsets, relatively little research has addressed the impact of such motivational orientations on performance and emotion in a real-time, multi-task setting. A laboratory simulation is reported that examines the influence of an induced approach-centered, an avoidance-centered, and a “neutral” motivational mindset upon multiple aspects of task performance, self-regulatory cognition, and affect. Undergraduate females randomly assigned to one of three mindset conditions performed a simulated automobile drive across one practice and two experimental trials. Dependent measures included divided attention, behavioral indicators of driving “cautiousness” in relatively safe straight roadway sections as well as during more risk-filled driving, multiple aspects of self-regulatory thinking (including self-monitoring, intended effort, and self-administered consequences), and positive and negative affect. Results revealed that the avoidant mindset produced poorer executive attention (i.e., fewer correctly detected divided attention events), more “cautious” driving behavior and reduced performance variability (i.e., greater control) when driving on presumably safe, straight roadway sections, lower self-reports of intended effort, and greater negative affect relative to the approach mindset. Results are intepreted within a self-regulation-centered motivational framework. Implications of the multi-task simulation for the study of normal and disordered adjustment are considered. 相似文献