全文获取类型
收费全文 | 3492篇 |
免费 | 193篇 |
国内免费 | 22篇 |
专业分类
耳鼻咽喉 | 134篇 |
儿科学 | 89篇 |
妇产科学 | 30篇 |
基础医学 | 449篇 |
口腔科学 | 86篇 |
临床医学 | 204篇 |
内科学 | 878篇 |
皮肤病学 | 75篇 |
神经病学 | 409篇 |
特种医学 | 70篇 |
外科学 | 561篇 |
综合类 | 14篇 |
预防医学 | 100篇 |
眼科学 | 58篇 |
药学 | 255篇 |
中国医学 | 7篇 |
肿瘤学 | 288篇 |
出版年
2022年 | 53篇 |
2021年 | 71篇 |
2020年 | 42篇 |
2019年 | 51篇 |
2018年 | 56篇 |
2017年 | 46篇 |
2016年 | 48篇 |
2015年 | 50篇 |
2014年 | 69篇 |
2013年 | 81篇 |
2012年 | 153篇 |
2011年 | 156篇 |
2010年 | 87篇 |
2009年 | 84篇 |
2008年 | 145篇 |
2007年 | 157篇 |
2006年 | 144篇 |
2005年 | 132篇 |
2004年 | 146篇 |
2003年 | 149篇 |
2002年 | 120篇 |
2001年 | 141篇 |
2000年 | 162篇 |
1999年 | 144篇 |
1998年 | 47篇 |
1997年 | 35篇 |
1996年 | 41篇 |
1995年 | 28篇 |
1994年 | 27篇 |
1993年 | 31篇 |
1992年 | 102篇 |
1991年 | 73篇 |
1990年 | 85篇 |
1989年 | 105篇 |
1988年 | 84篇 |
1987年 | 71篇 |
1986年 | 65篇 |
1985年 | 60篇 |
1984年 | 42篇 |
1983年 | 28篇 |
1982年 | 18篇 |
1980年 | 19篇 |
1979年 | 36篇 |
1978年 | 20篇 |
1977年 | 26篇 |
1976年 | 14篇 |
1975年 | 15篇 |
1974年 | 15篇 |
1968年 | 15篇 |
1966年 | 14篇 |
排序方式: 共有3707条查询结果,搜索用时 13 毫秒
81.
82.
83.
Otsuka M Uchida Y Kawaguchi T Taniguchi E Kawaguchi A Kitani S Itou M Oriishi T Kakuma T Tanaka S Yagi M Sata M 《Hepatology research》2012,42(10):982-989
Aim: Dietary habits are involved in the development of chronic inflammation; however, the impact of dietary profiles of hepatitis C virus carriers with persistently normal alanine transaminase levels (HCV‐PNALT) remains unclear. The decision‐tree algorithm is a data‐mining statistical technique, which uncovers meaningful profiles of factors from a data collection. We aimed to investigate dietary profiles associated with HCV‐PNALT using a decision‐tree algorithm. Methods: Twenty‐seven HCV‐PNALT and 41 patients with chronic hepatitis C were enrolled in this study. Dietary habit was assessed using a validated semiquantitative food frequency questionnaire. A decision‐tree algorithm was created by dietary variables, and was evaluated by area under the receiver operating characteristic curve analysis (AUROC). Results: In multivariate analysis, fish to meat ratio, dairy product and cooking oils were identified as independent variables associated with HCV‐PNALT. The decision‐tree algorithm was created with two variables: a fish to meat ratio and cooking oils/ideal bodyweight. When subjects showed a fish to meat ratio of 1.24 or more, 68.8% of the subjects were HCV‐PNALT. On the other hand, 11.5% of the subjects were HCV‐PNALT when subjects showed a fish to meat ratio of less than 1.24 and cooking oil/ideal bodyweight of less than 0.23 g/kg. The difference in the proportion of HCV‐PNALT between these groups are significant (odds ratio 16.87, 95% CI 3.40–83.67, P = 0.0005). Fivefold cross‐validation of the decision‐tree algorithm showed an AUROC of 0.6947 (95% CI 0.5656–0.8238, P = 0.0067). Conclusion: The decision‐tree algorithm disclosed that fish to meat ratio and cooking oil/ideal bodyweight were associated with HCV‐PNALT. 相似文献
84.
Hiroshi Sadamori Takahito Yagi Susumu Shinoura Yuzo Umeda Ryuichi Yoshida Daisuke Satoh Daisuke Nobuoka Masashi Utsumi Toshiyoshi Fujiwara 《Journal of gastrointestinal surgery》2013,17(2):403-407
Introduction
The management of a large splenorenal shunt is important because it affects recipient outcome, particularly in living donor liver transplantation.Methods
To manage large splenorenal shunts in living donor liver transplantation, we diverted superior mesenteric vein and splenic portal vein blood flow by ligation at the root of the splenic portal vein.Result
This procedure was applied for five patients in whom superior mesenteric vein blood flow had been completely stolen by a splenorenal shunt preoperatively. Postoperative course was excellent in all cases.Conclusion
This technique completely prevents morbidity related to large splenorenal shunts after living donor liver transplantation. 相似文献85.
86.
Plasmid-determined tetracycline resistance in Streptococcus faecalis: evidence for gene amplification during growth in presence of tetracycline. 总被引:33,自引:2,他引:33 下载免费PDF全文
D B Clewell Y Yagi B Bauer 《Proceedings of the National Academy of Sciences of the United States of America》1975,72(5):1720-1724
The tetracycline (TG)-resistant Streptococcus faecalis strain DS-5Cl harbors two plasmids designated alpha and gamma with molecular masses of approximately 6 and 35 million daltons, respectively. TC-sensitive variants were derived by storing cells at 45 degrees for 2-3 weeks. Analysis of covalently closed circular DNA from five such variants (derived independently) revealed that in each variant the alpha-plasmid, which normally sediments at 28 S (supercoiled) in a sucrose density gradient, was replaced by a 22S substance. Growth of DS-5Cl in the presence of 150 mug/ml of TC (minimum inhibitory concentration is 250 mug/ml in liquid broth) for a prolonged period of time (50-60 generations) resulted in the disappearance of 28S DNA and the appearance of a heterogeneous covalently-closed circular DNA sedimenting at about 40-48 S. This phenomenon was accompanied by an increase in the level of bacterial TC-resistance, whereby tells were subsequently grown in the absence of TC for 70-80 generations, the heterogeneous DNA disappeared and a typical 28S alpha-plasmid reappeared. The cells also became less resistant to TC, i.e., the minimum inhibitory concentration returned to 250 mug/ml. These data suggest that bacterial growth in the presence of TC results in a reversible gene amplification with respect to a TC-resistant determinant residing on the alpha-plasmid. 相似文献
87.
Satoshi Yamaji Shinobu Imai Fumio Saito Hiroshi Yagi Toshio Kushiro Takahisa Uchiyama 《Circulation journal》2006,70(2):190-197
BACKGROUND: Computed tomography (CT) is widely used in clinical practice, but there has not been a detailed report of its effect on the functioning of pacemakers. METHODS AND RESULTS: During CT, ECGs were recorded in 11 patients with pacemakers and the electromagnetic field in the CT room was also measured. The effect of CT on a pacemaker was also investigated in a human body model with and without shielding by rubber or lead. Transient malfunctions of pacemakers during CT occurred in 6 of 11 patients. The model showed that malfunctioning of the pacemaker was induced by CT scanning and this was prevented by lead but not by rubber. The alternating electrical field was 150 V/m on the CT scanning line, which was lower than the level influencing pacemaker functions. The alternating magnetic field was 15 muT on the CT scanning line, which was also lower than the level influencing pacemaker functions. CONCLUSIONS: Malfunctions of the pacemaker during CT may be caused by diagnostic radiant rays and although they are transient, the possibility of lethal arrhythmia cannot be ignored. 相似文献
88.
A. Tsunoda T. Takahashi K. Hayashi Y. Yagi H. Kusanagi 《Techniques in coloproctology》2018,22(6):425-431
Background
Physiological changes after laparoscopic ventral rectopexy (LVR) in patients with rectoanal intussusception (RAI) remain unclear. This study was undertaken to evaluate physiological and morphological changes after LVR for RAI, and to study clinical outcomes following LVR with special reference to fecal incontinence (FI).Methods
The study was conducted on patients who had LVR for RAI between February 2012 and December 2016 at our institution Patients with RAI and FI were included in the study. Patients with RAI and obstructed defecation and those with RAI and neurologic FI were not included. The patients had anorectal manometry preoperatively, and 3, 6, and 12 months postoperatively. Defecography was performed before and 6 months after the procedure. FI was evaluated using the Fecal Incontinence Severity Index (FISI).Results
There were 34 patients (median age 77 years (range 60–93) years). Thirty-two patients (94%) were female and the median number of vaginal deliveries was 2 (range 0–5). Neither maximum resting pressure nor maximum squeeze pressure increased postoperatively. There was an overall increase in both defecatory desire volume (median preoperative 75 ml vs. 90 ml at 12 months; p?=?0.002) and maximum tolerated volume (median preoperative 145 ml vs.175 ml at 12 months; p?=?0.002). Postoperatively, RAI was eliminated in all patients but one, although 13 had residual rectorectal intussusception found at defecography. There was an overall reduction in both rectocele size (median preop 29 mm vs. postop 10 mm; p?=?0.008) and pelvic floor descent (median preop 26 mm vs. postop 20 mm; p?=?0.005). Twelve months after surgery, a reduction of at least 50% was observed in the FISI score for 31 incontinent patients (91%).Conclusions
LVR for RAI produced adequate improvement of FI, and successful anatomical correction of RAI was confirmed by postoperative proctography. Postoperative increase in the rectal volume may have a positive effect on continence.89.