全文获取类型
收费全文 | 25946篇 |
免费 | 1204篇 |
国内免费 | 147篇 |
专业分类
耳鼻咽喉 | 279篇 |
儿科学 | 495篇 |
妇产科学 | 416篇 |
基础医学 | 3284篇 |
口腔科学 | 538篇 |
临床医学 | 1621篇 |
内科学 | 6338篇 |
皮肤病学 | 434篇 |
神经病学 | 2199篇 |
特种医学 | 1057篇 |
外科学 | 4106篇 |
综合类 | 112篇 |
一般理论 | 5篇 |
预防医学 | 794篇 |
眼科学 | 636篇 |
药学 | 1782篇 |
中国医学 | 29篇 |
肿瘤学 | 3172篇 |
出版年
2023年 | 118篇 |
2022年 | 291篇 |
2021年 | 492篇 |
2020年 | 288篇 |
2019年 | 370篇 |
2018年 | 478篇 |
2017年 | 382篇 |
2016年 | 438篇 |
2015年 | 489篇 |
2014年 | 600篇 |
2013年 | 780篇 |
2012年 | 1292篇 |
2011年 | 1330篇 |
2010年 | 766篇 |
2009年 | 649篇 |
2008年 | 1152篇 |
2007年 | 1287篇 |
2006年 | 1251篇 |
2005年 | 1173篇 |
2004年 | 1116篇 |
2003年 | 1085篇 |
2002年 | 1163篇 |
2001年 | 703篇 |
2000年 | 774篇 |
1999年 | 733篇 |
1998年 | 315篇 |
1997年 | 253篇 |
1996年 | 255篇 |
1995年 | 232篇 |
1994年 | 222篇 |
1993年 | 204篇 |
1992年 | 656篇 |
1991年 | 566篇 |
1990年 | 560篇 |
1989年 | 579篇 |
1988年 | 513篇 |
1987年 | 497篇 |
1986年 | 439篇 |
1985年 | 459篇 |
1984年 | 266篇 |
1983年 | 214篇 |
1982年 | 103篇 |
1981年 | 100篇 |
1979年 | 238篇 |
1978年 | 128篇 |
1977年 | 102篇 |
1975年 | 103篇 |
1974年 | 101篇 |
1970年 | 102篇 |
1969年 | 116篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Vasundhara Sridharan Yuichi Shoda Jaimee L. Heffner Jonathan Bricker 《Substance use & misuse》2019,54(7):1086-1095
Background: Lay belief systems about the malleability of human attributes have been shown to impact behavior change in multiple domains. Addiction mindset—i.e., beliefs about the permanence (vs. malleability) of addiction — may affect cigarette smokers’ ability to quit, but this has never been examined. Objectives: The aims of the present research were to develop a measure of addiction mindset (study 1) and examine its associations with various psychological aspects of quitting smoking (study 2). Methods: In Study 1, using factor analysis of current smokers’ and nonsmokers’ (n?=?600) responses to 22 items designed to measure addiction mindset, we developed a reliable six-item Addiction Mindset Scale (AMS). In Study 2, adult smokers (n?=?200) completed the AMS, and measures of a number of psychological processes related to smoking. Results: Higher scores on the AMS, indicative of the belief that addiction is malleable (referred to as a growth mindset), were positively and significantly associated with greater motivation to quit, greater commitment to quitting, greater self-efficacy to abstain, less attribution of failure to lack of ability to change addiction, and fewer self-reported barriers to cessation (all p’s < .05). Conclusions: The results of this study show a relationship between the beliefs about the permanence of addiction and psychological processes relevant to quitting smoking. The findings underscore the potential of future research exploring how addiction mindsets relate to successful smoking cessation as well as other types of addictive behavior and how they can be applied to change people’s behavior. 相似文献
2.
Zhenzhen Zhang Mark Garzotto Tomasz M. Beer Philippe Thuillier Stephen Lieberman Motomi Mori 《Nutrition and cancer》2016,68(8):1309-1319
Animal and human studies suggest fish oil and green tea may have protective effect on prostate cancer. Fatty acid synthase (FAS) has been hypothesized to be linked to chemoprotective effects of both compounds. This study evaluated the independent and joint effects of fish oil (FO) and green tea supplement (epigallocatechin-3-gallate, EGCG) on FAS and Ki-67 levels in prostate tissue. Through a double-blinded, randomized controlled trial with 2 × 2 factorial design, 89 men scheduled for repeat prostate biopsy following an initial negative prostate biopsy were randomized into either FO alone (1.9 g DHA + EPA/day), EGCG alone (600 mg/day), a combination of FO and EGCG, or placebo. We used linear mixed-effects models to test the differences of prostate tissue FAS and Ki-67 by immunohistochemistry between pre- and post-intervention within each group, as well as between treatment groups. Results did not show significant difference among treatment groups in pre-to-post-intervention changes of FAS (P = 0.69) or Ki-67 (P = 0.26). Comparing placebo group with any of the treatment groups, we did not find significant difference in FAS or Ki-67 changes (all P > 0.05). Results indicate FO or EGCG supplementation for a short duration may not be sufficient to produce biologically meaningful changes in FAS or Ki-67 levels in prostate tissue. 相似文献
3.
4.
5.
Masaru Sasaki Tsuyoshi Takahashi Soichiro Funaki Koji Tanaka Yasuhiro Miyazaki Naoko Ose Tomoki Makino Yukinori Kurokawa Makoto Yamasaki Kiyokazu Nakajima Yasushi Shintani Masaki Mori Yuichiro Doki 《Asian journal of endoscopic surgery》2021,14(1):116-119
We report a case of a diaphragmatic hernia after a heart transplant operation. A 43-year-old woman, who underwent orthotropic heart transplantation for hypertrophic cadiomyopathy two year earlier, presented with vomiting and epigastric pain. A computed tomography scan showed that the stomach and transverse colon were dislocated in the left thoracic cavity. We diagnosed left diaphragmatic hernia incarceration and performed laparoscopic repair of the diaphragmatic hernia. A 12 × 8 cm diaphragmatic defect was found intraoperatively on the ventrolateral aspect of the left diaphragm, and the stomach with volvulus had herniated into the thorax through the defect. The hernia was considered to be iatrogenic. The diaphragmatic defect was large, and the diaphragm was thinning. We closed the defect by mesh repair. Laparoscopic mesh repair of the diaphragmatic hernia could be performed safely and with minimal invasiveness. 相似文献
6.
7.
8.
9.
We examined stochastic resonance with a differential coding scheme using a multilayer feedforward neural network which is composed of intra-layer connections. We show that the network, with random synaptic connections in each layer, encodes an input signal into a spike coherence that represents temporal differences among the inputs. We also demonstrate that both internal and external noise enhance the detection of weak signals. Finally, we discuss how the feedforward network with intra-layer random connections is similar to a membrane in its sensitivity to and amplification of a change in stimulus and suggest that the intensity of internal noise may be tuned in a real brain. 相似文献
10.
Takako Miyamae Masaaki Mori Yasuji Inamo Youichi Kohno Shuji Takei Motoharu Maeda Takuji Murata Shuji Nakata Hiroshi Kawai Yukiko Hirano Yukiji Date Katsuhiko Kitamura Shumpei Yokota 《Ryūmachi》2003,43(3):538-543
OBJECTIVES: To reveal the frequency and the clinical characteristics of dystrophic calcification that occurs in children with juvenile dermatomyositis, multi-center analysis was constructed. METHOD: Fifty children with JDM were enrolled, and 14 of them (28.0%) were complicated with calcinosis. Clinical symptoms and laboratory tests at onset, initial therapy and disease course were compared in children with and without calcinosis. RESULTS: The mean age of the onset of calcinosis was 4.78 +/- 3.33 years, and it was younger than those of children without calcinosis (8.66 +/- 3.85 years) (P = 0.0017). No differences of clinical manifestation except Gower's sign were observed. The frequency of positive anti-nuclear antibody was 7.1% in children with calcinosis and 52.9% without calcinosis (P = 0.0112). The initial therapy of methylprednisolon pulses gave no effects on prognosis of calcium deposition. The calcinosis appeared in 1.56 +/- 1.91 year after the onset of the disease. The various types of calcium deposition including large tumorous clumps, subcutaneous plaques or nodules, sheet-type calcification were deserved. They appeared over knee joints (64.3%), elbow joint (64.3%), and hip processes (50.0%). Calcinosis affecting the subcutaneous tissues frequently resulted in painful superficial ulceration of the overlying skin (42.9%), local infection (50.0%), and limitation of joint movement (14.3%). Although aluminum phosphate was effective in 2 children among 7, no other effective treatment was recommended. In 5 cases, surgical removal of tumorous clumps was operated. Thus, juvenile dermatomyositis is frequently complicated with calcinosis. This type of calcinosis was found to be unlikely to resolve completely, and resulted in severe disability in children. 相似文献