全文获取类型
收费全文 | 12216篇 |
免费 | 639篇 |
国内免费 | 85篇 |
专业分类
耳鼻咽喉 | 113篇 |
儿科学 | 236篇 |
妇产科学 | 57篇 |
基础医学 | 1354篇 |
口腔科学 | 354篇 |
临床医学 | 807篇 |
内科学 | 3150篇 |
皮肤病学 | 294篇 |
神经病学 | 905篇 |
特种医学 | 385篇 |
外科学 | 2315篇 |
综合类 | 41篇 |
预防医学 | 314篇 |
眼科学 | 287篇 |
药学 | 976篇 |
中国医学 | 19篇 |
肿瘤学 | 1333篇 |
出版年
2023年 | 54篇 |
2022年 | 139篇 |
2021年 | 266篇 |
2020年 | 160篇 |
2019年 | 201篇 |
2018年 | 278篇 |
2017年 | 205篇 |
2016年 | 261篇 |
2015年 | 274篇 |
2014年 | 318篇 |
2013年 | 409篇 |
2012年 | 700篇 |
2011年 | 757篇 |
2010年 | 460篇 |
2009年 | 357篇 |
2008年 | 679篇 |
2007年 | 719篇 |
2006年 | 729篇 |
2005年 | 651篇 |
2004年 | 614篇 |
2003年 | 581篇 |
2002年 | 547篇 |
2001年 | 284篇 |
2000年 | 291篇 |
1999年 | 320篇 |
1998年 | 130篇 |
1997年 | 110篇 |
1996年 | 126篇 |
1995年 | 103篇 |
1994年 | 94篇 |
1993年 | 68篇 |
1992年 | 186篇 |
1991年 | 190篇 |
1990年 | 149篇 |
1989年 | 191篇 |
1988年 | 178篇 |
1987年 | 166篇 |
1986年 | 125篇 |
1985年 | 145篇 |
1984年 | 94篇 |
1983年 | 65篇 |
1982年 | 42篇 |
1981年 | 32篇 |
1980年 | 33篇 |
1979年 | 51篇 |
1978年 | 30篇 |
1976年 | 34篇 |
1975年 | 29篇 |
1969年 | 39篇 |
1967年 | 34篇 |
排序方式: 共有10000条查询结果,搜索用时 640 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.
3.
4.
Sugar and tooth decays are bound closely. The mechanisms of destruction of the tooth from the glycolyse are known. The role played by the food in the development of the caries is unique. Foods sweetened of all ways, rich in sucrose are responsible of the intervening of the carious lesions. The transformation of the fermentable sugars in lactic with the absence of hygiene and the action conjugated of the bacteria leads to tooth decays in temporary and permanent denture that evolve very quickly in the absence of treatment. Reasons for which the authors put in evidence in this survey, the influence of the food sweetened on the teeth at the children while showing the cases of caries and its complications due to the excessive consumption of fermentable hydrates of carbon. 相似文献
5.
The absence of the temporary incisors could be to a genetic illness or to some multiple premature extractions. These extractions are the aftermaths of the carious lesions or some traumatisms underwent by the temporary incisors. Beyond measure the loss of the space, the premature loss some temporary incisors very often assign the relational development of the child and disturb its psychological development and the aesthetic function. Across some cases clinics, the authors show that the replacement of the temporary incisors is the therapeutic ideal solution. Indeed, the child prosthesis, replacing the temporary absent incisors, solves the psychological, aesthetic and relational problems of the child. 相似文献
6.
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
7.
Nobuaki Yanagisawa Shinichi Abe Hiroko Agematsu Koji Sakiyama Akinobu Usami Yuichi Tamatsu Yoshinobu Ide 《Annals of anatomy》2006,188(4):329-336
To elucidate the effects of teeth on muscle fibers in the tongue during the developmental process, we examined the expression of muscle contractile proteins and the genes for those proteins in normal mice and microphthalmic (mi/mi) mice with impaired tooth eruption. The mice were observed during the growth period, including weaning, which is when feeding movements undergo major changes. Expression of the myosin heavy chain (MyHC)-2a protein, whose contraction speed is relatively slow, disappeared after weaning in normal mice, while it remained in high concentrations even after weaning in mi/mi mice. The presence of MyHC-2a after weaning in mice with no tooth eruption was attributed to a compensation for lack of proper masticatory function and sucking-like movements, as MyHC-2a is necessary for these movements. 相似文献
8.
Y Ogawa T Nishimura K Hayashida I Yokota S Imakita S Kumita T Uehara T Shimonagata H Oka M Nakamura 《Kaku igaku. The Japanese journal of nuclear medicine》1991,28(6):599-607
99mTc-ECD SPECT was performed in 19 patients with cerebrovascular disease, and location, extent, and severity of the lesions on 99mTc-ECD SPECT were compared with those on 123I-IMP SPECT. The initial brain uptake was 5.5 +/- 0.7% of the injected dose at 10 minutes after injection, 5.3 +/- 1.3% at 90 minutes, and clearance from the brain is slow. The distribution in the brain was changed, especially washout from the thalamus was slower than that from other regions. The count ratio of perfusion defect to normal area (D/N) on 99mTc-ECD SPECT was unchanged over the time, and had no significant differences from that on 123I-IMP SPECT. 99mTc-ECD SPECT was superior in detection of the lesion in the basal ganglia, and showed the images with superior spatial resolution due to physical characteristics of 99mTc. However, mild ischemic lesion and peri-infarct area was not clearly visualized, while 123I-IMP SPECT could demonstrate these lesions with better contrast. 相似文献
9.
We report an 80-year-old Japanese male with four primary malignant tumors: malignant melanoma, prostatic cancer, malignant lymphoma, and renal cell carcinoma, which occurred in that respective order. The combination of malignant melanoma and malignant lymphoma is rare. The patient was treated with BCG after an operation for malignant melanoma. He was also treated with cobalt 60 irradiation after an operation for prostatic cancer. We also discuss other reports of multiple malignant tumors and suggest some possible causes of this patient's primary malignant tumors. 相似文献
10.