全文获取类型
收费全文 | 12384篇 |
免费 | 597篇 |
国内免费 | 48篇 |
专业分类
耳鼻咽喉 | 132篇 |
儿科学 | 314篇 |
妇产科学 | 85篇 |
基础医学 | 1496篇 |
口腔科学 | 503篇 |
临床医学 | 702篇 |
内科学 | 3243篇 |
皮肤病学 | 152篇 |
神经病学 | 882篇 |
特种医学 | 477篇 |
外科学 | 2213篇 |
综合类 | 71篇 |
预防医学 | 389篇 |
眼科学 | 319篇 |
药学 | 846篇 |
中国医学 | 17篇 |
肿瘤学 | 1188篇 |
出版年
2023年 | 66篇 |
2022年 | 92篇 |
2021年 | 245篇 |
2020年 | 130篇 |
2019年 | 177篇 |
2018年 | 219篇 |
2017年 | 182篇 |
2016年 | 205篇 |
2015年 | 211篇 |
2014年 | 278篇 |
2013年 | 388篇 |
2012年 | 587篇 |
2011年 | 656篇 |
2010年 | 368篇 |
2009年 | 311篇 |
2008年 | 587篇 |
2007年 | 626篇 |
2006年 | 639篇 |
2005年 | 606篇 |
2004年 | 574篇 |
2003年 | 577篇 |
2002年 | 592篇 |
2001年 | 411篇 |
2000年 | 373篇 |
1999年 | 400篇 |
1998年 | 145篇 |
1997年 | 107篇 |
1996年 | 108篇 |
1995年 | 101篇 |
1994年 | 90篇 |
1993年 | 71篇 |
1992年 | 277篇 |
1991年 | 245篇 |
1990年 | 242篇 |
1989年 | 276篇 |
1988年 | 208篇 |
1987年 | 197篇 |
1986年 | 195篇 |
1985年 | 175篇 |
1984年 | 133篇 |
1983年 | 102篇 |
1982年 | 68篇 |
1981年 | 51篇 |
1979年 | 78篇 |
1978年 | 50篇 |
1977年 | 51篇 |
1975年 | 49篇 |
1974年 | 49篇 |
1973年 | 49篇 |
1966年 | 47篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
Toshiro Hara Rony Chanoch-Myers Nathan D. Mathewson Chad Myskiw Lyla Atta Lillian Bussema Stephen W. Eichhorn Alissa C. Greenwald Gabriela S. Kinker Christopher Rodman L. Nicolas Gonzalez Castro Hiroaki Wakimoto Orit Rozenblatt-Rosen Xiaowei Zhuang Jean Fan Tony Hunter Inder M. Verma Kai W. Wucherpfennig Itay Tirosh 《Cancer cell》2021,39(6):779-792.e11
3.
4.
5.
Nobuhiko Joki Hiroki Hase Yuri Tanaka Yasunori Takahashi Tomokatsu Saijyo Hiroyaou Ishikawa Yoji Inishi Yoshihiko Imamura Hisao Hara Taro Tsunoda Masato Nakamura 《Nephrology, dialysis, transplantation》2006,21(6):1633-1639
BACKGROUND: In patients with chronic kidney disease (CKD), although strong associations have been observed between malnutrition and atherosclerosis, the relationship between serum albumin concentration and angiographic changes of coronary artery disease (CAD) remains poorly explored. The goal of the present study was, in patients with CKD, to clarify the relationship between the angiographic severity of CAD and serum albumin concentration reflecting either inflammation or nutrition or both. METHODS: In this study, 100 end-stage renal disease (ESRD) patients were enrolled, who commenced long-term dialysis therapy at our hospital and underwent coronary angiography within 3 months of the first haemodialysis (HD) session. Mean age was 63+/-11 years, 20% of the subjects were female and 62% had diabetes. Severity of CAD was evaluated in terms of (i) number of vessels exhibiting CAD (>or=75% stenosis) and (ii) Gensini score (GS). Clinical characteristics and laboratory findings were recorded at initiation of long-term HD therapy. We then evaluated a possible association with the presence and degree of CAD. RESULTS: Sixty-four patients exhibited signs of CAD. Forty-one among them (64%) had multivessel disease. On univariate logistic regression analysis, age, diabetes and hypoalbuminaemia were significantly associated with multivessel CAD. Univariate linear regression analysis demonstrated a positive correlation of age and diabetes with GS, and an inverse correlation of BMI and serum albumin level with GS. Stepwise regression analysis showed age and serum albumin level to be independently associated with multivessel CAD and GS. The ROC curves demonstrated best cut-off levels of age and albumin for predicting multivessel CAD to be 70 years and 3.15 g/dl, respectively. CONCLUSION: Hypoalbuminaemia at the initiation of dialysis is an important predictor of advanced CAD, particularly in male and in diabetic patients. It may reflect mainly a state of inflammation. However, malnutrition as a confounding factor cannot be entirely excluded. 相似文献
6.
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
7.
8.
M Sasa M Hara S Takaori 《Progress in neuro-psychopharmacology & biological psychiatry》1991,15(1):119-128
1. Spike generation by stimulation of the parafascicular nucleus of thalamus was extracellularly recorded in the nucleus accumbens of chloral hydrate-anesthetized adult Wistar rats using a silver-wire microelectrode attached along a seven-barreled micropipette, each of which was filled with dopamine, SKF 38393 (D-1 agonist), bromocriptine (D-2 agonist), haloperidol, SCH 23390 (D-1 antagonist) and domperidone (D-2 antagonist). The drugs were microiontophoretically applied to the target neurons recorded. 2. Effects of dopamine receptor antagonists on the inhibition of the spike generation by conditioning stimuli applied to the ventral tegmental area preceding the test stimulus to the parafascicular nucleus and those of dopamine agonists on the test stimulus-induced spikes were examined. 3. The parafascicular nucleus stimulation-induced spikes were inhibited by dopamine as well as D-1 and D-2 agonists and by the conditioning stimulation of the ventral tegmental area. The conditioning stimulation-induced inhibition was antagonized by haloperidol and SCH 23390, but not by domperidone. 4. Activation of D-1 receptors, which make probably synaptic contact with dopaminergic nerve terminals from the ventral tegmental area, is considered to result in inhibition of the neuronal activity of the nucleus accumbens neurons receiving input from the parafascicular nucleus of the thalamus. In addition, D-2 receptors located extrajunctionally may be involved in the inhibition of the same neurons in the nucleus accumbens. 相似文献
9.
Nishida Koyo Mihara Kiyoshi Takino Toichi Nakane Sachi Takakura Yoshinobu Hashida Mitsuru Sezaki Hitoshi 《Pharmaceutical research》1991,8(4):437-444
The effect of electric charge on the hepatic disposition of macromolecules was studied in the rat. Charged derivatives of dextran (T-70) and bovine serum albumin (BSA), mitomycin C–dextran conjugates (MMC-D), and lactosaminated BSA (Lac-BSA) were employed as model macromolecules. After intravenous injection, cationic macromolecules were rapidly eliminated from plasma because of their extensive hepatic uptake, while anionic and neutral macromolecules were slowly eliminated. Cationic macromolecules were recovered from parenchymal and nonparenchymal hepatic cells at a cellular uptake (per unit cell number) ratio of 1.4–3.2, while that of Lac-BSA was 14. During liver perfusion using a single-pass constant infusion mode, cationic macromolecules were continuously extracted by the liver, with extraction ratios at steady-state (E
ss) ranging between 0.03 and 0.54, whereas anionic and neutral macromolecules were almost completely recovered in the outflow at steady state. The E
ss for cationized BSA (Cat-BSA) and cationic MMC-Dcat were concentration dependent and decreased at low temperatures and in the presence of colchicine and cytochalasin B. The possible participation of the internalization process in the uptake of cationic macromolecules by hepatocytes was suggested. 相似文献
10.
Yoshinobu Okabe Osamu Tsuruta Yoshiki Naito Hideya Suga Michio Sata 《Digestive endoscopy》2007,19(Z1):S121-S125
Regarding peroral cholangioscopy (POCS) for biliary disease, due to the recent appearance of a video cholangioscope that can obtain high‐quality images, it is possible to observe subtle changes of the biliary mucosa. In addition to the conventional observation method using POCS, the biliary mucosa with also observed with narrow band imaging (NBI) in one case of chronic cholangitis and four cases of extra hepatic bile duct tumor (three surgical cases). In the conventional observation method, the vessels in the surface layer of the biliary mucosa could be observed more clearly using NBI. In one case in which a tumor was observed, the irregularity of the biliary mucosa became clear on NBI, and the vessels inside a papillary tumor could also be easily observed. In another case of bile duct tumor, the conventional observation method showed a region in the proximity of the tumor where the vessels could not be seen clearly, but they could be seen clearly on NBI. In all of the cases, the bile juice was seen as red on NBI, which disturbed the observation. With POCS using NBI, it was possible to observe the vessels and irregularities in the surface layer of the biliary mucosa more clearly than with conventional observation methods. 相似文献