全文获取类型
收费全文 | 4738篇 |
免费 | 259篇 |
国内免费 | 31篇 |
专业分类
耳鼻咽喉 | 36篇 |
儿科学 | 162篇 |
妇产科学 | 55篇 |
基础医学 | 479篇 |
口腔科学 | 105篇 |
临床医学 | 372篇 |
内科学 | 1456篇 |
皮肤病学 | 47篇 |
神经病学 | 377篇 |
特种医学 | 122篇 |
外科学 | 906篇 |
综合类 | 17篇 |
预防医学 | 171篇 |
眼科学 | 64篇 |
药学 | 206篇 |
中国医学 | 20篇 |
肿瘤学 | 433篇 |
出版年
2023年 | 47篇 |
2022年 | 100篇 |
2021年 | 180篇 |
2020年 | 99篇 |
2019年 | 119篇 |
2018年 | 133篇 |
2017年 | 101篇 |
2016年 | 136篇 |
2015年 | 103篇 |
2014年 | 152篇 |
2013年 | 203篇 |
2012年 | 272篇 |
2011年 | 307篇 |
2010年 | 154篇 |
2009年 | 125篇 |
2008年 | 224篇 |
2007年 | 237篇 |
2006年 | 181篇 |
2005年 | 202篇 |
2004年 | 215篇 |
2003年 | 185篇 |
2002年 | 220篇 |
2001年 | 86篇 |
2000年 | 91篇 |
1999年 | 77篇 |
1998年 | 63篇 |
1997年 | 39篇 |
1996年 | 32篇 |
1995年 | 37篇 |
1994年 | 23篇 |
1993年 | 26篇 |
1992年 | 80篇 |
1991年 | 61篇 |
1990年 | 63篇 |
1989年 | 70篇 |
1988年 | 71篇 |
1987年 | 71篇 |
1986年 | 67篇 |
1985年 | 55篇 |
1984年 | 43篇 |
1983年 | 26篇 |
1980年 | 17篇 |
1979年 | 32篇 |
1978年 | 15篇 |
1977年 | 15篇 |
1976年 | 16篇 |
1975年 | 15篇 |
1972年 | 18篇 |
1971年 | 18篇 |
1970年 | 14篇 |
排序方式: 共有5028条查询结果,搜索用时 0 毫秒
71.
Yang Liu Yoshifumi Baba Takatsugu Ishimoto Hiroyasu Tsutsuki Tianli Zhang Daichi Nomoto Kazuo Okadome Kensuke Yamamura Kazuto Harada Kojiro Eto Yukiharu Hiyoshi Masaaki Iwatsuki Yohei Nagai Shiro Iwagami Yuji Miyamoto Naoya Yoshida Yoshihiro Komohara Masaki Ohmuraya Xiaoming Wang Jaffer A. Ajani Tomohiro Sawa Hideo Baba 《British journal of cancer》2021,124(5):963
Background Fusobacterium nucleatum (F. nucleatum) is a gut microbe implicated in gastrointestinal tumorigenesis. Predicting the chemotherapeutic response is critical to developing personalised therapeutic strategies for oesophageal cancer patients. The present study investigated the relationship between F. nucleatum and chemotherapeutic resistance in oesophageal squamous cell carcinoma (ESCC).Methods We examined the relationship between F. nucleatum and chemotherapy response in 120 ESCC resected specimens and 30 pre-treatment biopsy specimens. In vitro studies using ESCC cell lines and co-culture assays further uncovered the mechanism underlying chemotherapeutic resistance.Results ESCC patients with F. nucleatum infection displayed lesser chemotherapeutic response. The infiltration and subsistence of F. nucleatum in the ESCC cells were observed by transmission electron microscopy and laser scanning confocal microscopy. We also observed that F. nucleatum modulates the endogenous LC3 and ATG7 expression, as well as autophagosome formation to induce chemoresistance against 5-FU, CDDP, and Docetaxel. ATG7 knockdown resulted in reversal of F. nucleatum-induced chemoresistance. In addition, immunohistochemical studies confirmed the correlation between F. nucleatum infection and ATG7 expression in 284 ESCC specimens.Conclusions F. nucleatum confers chemoresistance to ESCC cells by modulating autophagy. These findings suggest that targeting F. nucleatum, during chemotherapy, could result in variable therapeutic outcomes for ESCC patients.Subject terms: Tumour biomarkers, Oesophageal cancer 相似文献
72.
73.
Kensuke Suenaga M.D. Yuichi Yokoyama M.D. kazuichi Okazaki M.D. Yasutake Yamamoto M.D. 《The American journal of gastroenterology》1995,90(1):76-80
Objectives : It is still controversial whether or not a mycobacterial infection may be a cause of Crohn's disease. Mycobaclerium paratuberculosis may be very difficult to detect using routine culture techniques. To clarify this, we delected mycobacterial DNA in patients with inflammatory bowel disease. Methods : IS900 sequences highly specific to M. paratuberculosis and groEL gene encoding a conserved mycobacterial antigen were studied in colonic mucosa using polymerase chain reaction (PCR). PCR products were analyzed by Southern blot hybridization. Results : IS900 sequences were detected in all (100%)of 10 patients with Crohan's disease, in 11 (61.1%) of 18 patients with ulcerative colitis, and in 14 (87.5%) of 16 control patients with noninflammatory bowel disease. All IS900 positive samples had groEL PCR products. Conclusions : Our results, on the basis of the prevalence, do not support the hypothesis that M. paratuberculosis is involved in the pathogenesis of Crohn's disease. 相似文献
74.
Burst patterns in the digastric, mylohyoid, and masseter muscles and the resultant jaw movement orbits during chewing and
swallowing were investigated in the freely behaving rabbit. Activities in the posterior mylohyoid fibers consisted of two
continuous bursts. Peaks in the first burst of the posterior fibers occurred in the middle part of opening and preceded the
digastric burst. Peaks in the second burst occurred in the final part of opening and coincided with those in the working side
of the digastric burst. After removal of the bilateral digastric muscles, the gape size during chewing was largely reduced
in the final part of opening and in the early part of closing. The results suggest that (a) the digastric may have a role
in opening the mandible widely beyond the rest position but may not have a major role in the control of the horizontal (mediolateral)
jaw movement, (b) the posterior mylohyoid fibers may have a function as an elevator of the tongue in the early part of opening,
and (c) the posterior mylohyoid fibers may have a function as a depressor of the jaw in the late part of opening. Electromyographic
burst in the mylohyoid muscle began with marked activity in the mid-closing phase. The results support a role for the mylohyoid
muscle as a leading muscle of swallowing. Swallowing events in the rabbit are easily distinguished from the activities of
the mylohyoid muscle and the thyrohyoid muscle. 相似文献
75.
Azuma A Matsuo A Nakamura T Kawasaki T Yamamoto K Hyogo M Hirata A Hirasaki S Shima T Sugihara H Kunishige H Kuribayashi T Nakagawa M 《Japanese circulation journal》1999,63(5):333-338
To analyze the recent change in the long-term survival of patients with dilated cardiomyopathy (DCM), the present study comprised consecutive 111 patients with ejection fraction <50% and left ventricular end-diastolic diameter >58 mm. who were admitted to hospital from January 1983 to December 1994. The patients were divided into 2 groups: group A who were diagnosed before 1989 and group B diagnosed after 1990. Basic characteristics at diagnosis, including age, NYHA functional class, left ventricular end-diastolic diameter and ejection fraction, were similar between these 2 groups. Calculated survival rate at 5 years was 90.0% in group B in contrast to 62.3% in group A. Event-free survival also improved in group B. In group B, beta-blockers and angiotensin converting enzyme inhibitors were more frequently used than in group A (p<0.0001) whereas digitalis and other positive inotropic agents were significantly less used. Left ventricular ejection fraction was significantly improved during the follow-up period in patients treated with beta-blockers compared with those not treated with beta-blockers. These data indicate a significant improvement in the survival of patients with dilated cardiomyopathy after 1990, which may be explained by the change of medical treatment, especially the use of beta-blockers. 相似文献
76.
Kazuhiro Uda Kensuke Shoji Chitose Koyama-Wakai Munehiro Furuichi Noriyasu Iwase Seiichiro Fujisaki Shinji Watanabe Isao Miyairi 《Journal of infection and chemotherapy》2018,24(6):407-413
Background
Influenza A(H1N1)pdm09 virus infections often manifest severe respiratory symptoms, particularly in patients with a past history of allergic disease. Most of these findings were reported during the 2009 pandemic. The purpose of this study was to detail the clinical characteristics of influenza virus-induced lower respiratory infection (LRI) during the A(H1N1)pdm09-predominant 2015–2016 season.Methods
We retrospectively reviewed the clinical characteristics of influenza-induced LRI cases in children admitted to a tertiary children's hospital. Molecular diagnostic evaluation was performed on samples obtained from the most severe cases.Results
We identified 66 patients with influenza-associated hospitalization and included 21 patients with influenza virus-induced LRI for analyses. Twelve patients (57%) were admitted to the pediatric intensive care unit, seven (33%) required mechanical ventilation, and three (14%) required extracorporeal membrane oxygenation. Plastic bronchitis (PB) was identified in six patients (29%), among whom a past medical history of asthma or food allergy were noted in all six patients. A past history of allergic disease was more common among patients with, than among those without, PB (p = 0.009). A(H1N1)pdm09 was detected from all the PB cases, and phylogenetic analyses of the hemagglutinin and neuraminidase genes demonstrated that this virus belonged to subclades 6B.1 and 6B.2. In the six PB cases, we found one patient with H275Y mutation in neuraminidase.Conclusion
Allergic disease was a risk factor for developing PB due to influenza A(H1N1)pdm09 infection during the 2015–16 season. 相似文献77.
78.
Ritsuko Nishide Michiko Ando Hidemitsu Funabashi Yoshiko Yoda Masataka Nakano Masayuki Shima 《Environmental health and preventive medicine》2015,20(2):116-122
Objectives
To investigate the association of serum lipids and high-sensitivity C-reactive protein (hs-CRP) with obesity in school children and to explore whether hs-CRP levels could be used to predict the presence or absence of obesity 12 months later.Methods
The subjects were school children (6–11 years old) in Japan. Blood sampling and physical measurements were performed in school (2001); low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglycerides, and hs-CRP levels were measured. Data from children who could be followed 12 months later were analyzed. Subjects weighing 20 % or more over his/her standard weight were regarded as obese, and the association of obesity with serum parameters was analyzed.Results
Data from 612 subjects were analyzed (follow-up rate, 75.4 %). The mean of each serum parameter was significantly higher (inverse for HDL-C; lower) in obese than that in non-obese children. Logistic regression analysis for obesity at baseline showed that the odds ratio (OR) of hs-CRP was the highest [OR, 2.15; 95 % confidence interval (CI), 1.65–2.78 for an interquartile rage (IQR) increase]; the association with triglycerides and LDL-C/HDL-C was significant. At the 12-month follow-up, the OR of high hs-CRP remained the highest of all serum parameters (2.09; 95 % CI, 1.63–2.69 for an IQR increase).Conclusions
High levels of triglycerides, LDL-C/HDL-C, and hs-CRP increased the risk of obesity in school children. Hs-CRP is considered to be a better predictor of obesity 12 months later than is LDL-C/HDL-C. 相似文献79.
Muhammad Mohsin Hossain Md. Akherul Islam Hossain Shima Mudassir Hasan Muhammad Hilal Moonyong Lee 《RSC advances》2018,8(30):16927
Zinc acetate is recrystallized as lumber-shaped tetragonal rods by a novel recrystallization technique. Subsequently, the recrystallized zinc acetate is converted into ZnO nanorods in a glass vial by the simplest and cheapest method without utilizing any expensive instrumentation. Carbon is doped in ZnO nanorods during the preparation ZnO nanorods without any extra steps, chemicals, or effort. The carbon-doped ZnO nanorods can be dispersed in a solvent at very high concentrations and are also stable for a very long time, which are comparatively higher than those of the other existing ZnO nanoparticles. The higher dispersion concentration and higher stability of ZnO nanoparticles are explained by a scheme that demonstrates the suspending mechanism of the ZnO nanoparticles at higher concentrations with higher stabilities in a solvent through the anchoring groups of carbon. No materials are used for surface modification; no surface coatings, ionic materials, or pH controlling materials are used to increase the dispersion concentration and stability. This is the first observation of the doped carbon playing a significant role in the dispersion of ZnO nanoparticles at higher concentrations by withholding them in the solvent. Therefore, doped carbon at the surface of ZnO nanoparticles prevents the self-aggregation of ZnO nanoparticles in the solution phase by interfacial barrier layers among ZnO nanorods and interfacial interactive layer between ZnO nanorod and solvent.Dispersed ZnO hexagonal nanorods in ethanol solvent and its interfacial behavior in this liquid phase. 相似文献