全文获取类型
收费全文 | 5264篇 |
免费 | 304篇 |
国内免费 | 36篇 |
专业分类
耳鼻咽喉 | 41篇 |
儿科学 | 89篇 |
妇产科学 | 31篇 |
基础医学 | 699篇 |
口腔科学 | 77篇 |
临床医学 | 335篇 |
内科学 | 1493篇 |
皮肤病学 | 104篇 |
神经病学 | 424篇 |
特种医学 | 215篇 |
外科学 | 890篇 |
综合类 | 34篇 |
一般理论 | 3篇 |
预防医学 | 124篇 |
眼科学 | 66篇 |
药学 | 325篇 |
中国医学 | 22篇 |
肿瘤学 | 632篇 |
出版年
2024年 | 7篇 |
2023年 | 77篇 |
2022年 | 141篇 |
2021年 | 225篇 |
2020年 | 132篇 |
2019年 | 187篇 |
2018年 | 244篇 |
2017年 | 124篇 |
2016年 | 153篇 |
2015年 | 156篇 |
2014年 | 197篇 |
2013年 | 231篇 |
2012年 | 410篇 |
2011年 | 474篇 |
2010年 | 241篇 |
2009年 | 195篇 |
2008年 | 325篇 |
2007年 | 343篇 |
2006年 | 328篇 |
2005年 | 305篇 |
2004年 | 280篇 |
2003年 | 250篇 |
2002年 | 234篇 |
2001年 | 42篇 |
2000年 | 25篇 |
1999年 | 30篇 |
1998年 | 35篇 |
1997年 | 27篇 |
1996年 | 20篇 |
1995年 | 20篇 |
1994年 | 36篇 |
1993年 | 27篇 |
1992年 | 11篇 |
1991年 | 7篇 |
1990年 | 5篇 |
1989年 | 5篇 |
1988年 | 8篇 |
1987年 | 13篇 |
1986年 | 8篇 |
1985年 | 3篇 |
1984年 | 6篇 |
1983年 | 5篇 |
1982年 | 3篇 |
1981年 | 1篇 |
1980年 | 2篇 |
1974年 | 2篇 |
1972年 | 1篇 |
1971年 | 1篇 |
1968年 | 1篇 |
1959年 | 1篇 |
排序方式: 共有5604条查询结果,搜索用时 15 毫秒
41.
Nobuyoshi Kawakita Shuichi Seki Hiroki Sakaguchi Atsushi Yanai Kazuki Nakatani Takao Yamada Takuya Kitada Yasuhiko Sakai Tetsuo Kuroki Kenzo Kobayashi Takeyuki Monna 《Liver international》1994,14(6):295-301
ABSTRACT: The retinoblastoma gene product is a nuclear phosphoprotein that undergoes cell cycle-dependent changes in its phosphorylation status. To analyze the expression of retinoblastoma gene product in the process of liver regeneration and the initiation of hepatocellular carcinoma, we studied immunohistochemically the expression of retinoblastoma gene product and DNA polymerase alpha (DPA) in 33 patients with various liver diseases. Only a few hepatocytes positive for retinoblastoma gene product were found in undamaged, nonregenerating liver tissues, whereas many hepatocytes positive for retinoblastoma gene product were detected in specimens of regenerating liver obtained from patients with acute or chronic liver diseases. Similarities were found between distribution patterns of hepatocytes positive for retinoblastoma gene product and those of hepatocytes positive for DPA, and a highly significant positive correlation was found between the number of hepatocyte nuclei stained for retinoblastoma gene product per 1000 nuclei examined (R-LI) and the number of hepatocyte nuclei stained for DPA per 1000 nuclei examined (D-LI) in tissues obtained from patients with nonmalignant liver disease. Hepatocellular carcinoma cells positive for DPA were detected in the 14 hepatocellular carcinoma specimens tested. In ten of these specimens, hepatocellular carcinoma cells positive for retinoblastoma gene product were found but not in the other four. For all hepatocellular carcinoma specimens, R-LI was proportional to D-LI. Thus in both nonmalignant and malignant liver, retinoblastoma gene product increased in proportion to proliferation of hepatocytes or hepatocellular carcinoma cells. 相似文献
42.
Takuya Umehara Ryo Tanaka 《Revista brasileira de fisioterapia (S?o Carlos (S?o Paulo, Brazil))》2018,22(4):265-275
Background
Various systematic reviews and/or meta-analyses examining the effects of pre- or postoperative exercise on body function or activity in patients undergoing total knee arthroplasty (TKA) have been published. However, the interventional period needed to at least improve outcomes is unknown.Objective
The aim of this systematic review and meta-analysis was to investigate the exercise intervention period needed to effectively improve body function or activity before and after TKA in patients with knee osteoarthritis (OA).Methods
Studies published until July 2017 were included in the review. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach was applied to each meta-analysis to determine the quality of the evidence.Results
Twenty-seven randomized controlled trials were identified. A meta-analysis indicated that exercises performed for 8 weeks after discharge in addition to standard postoperative intervention effectively improved body function as assessed using pain level; physical function, and stiffness on the Western Ontario and McMaster Universities Arthritis Index; extension strength; active knee flexion range of motion; timed up and go test; and gait speed.Conclusion
Overall, we found low- to moderate-quality evidence that an 8-week exercise period was needed after discharge to improve body function and activity in patients with knee OA undergoing TKA. 相似文献43.
Yuzo Yamasaki Satoshi Kawanami Takeshi Kamitani Koji Sagiyama Seitaro Shin Takuya Hino Hazumu Nagata Hidetake Yabuuchi Michinobu Nagao Hiroshi Honda 《The international journal of cardiovascular imaging》2018,34(9):1485-1491
To investigate the performance of second-generation 320-row computed tomographic (CT) angiography (CTA) in detecting coronary arteries and identify factors influencing visibility of the coronary arteries in infants with complex congenital heart disease (CHD). Data of 60 infants (aged 0–2 years, median 2 months) with complex CHD who underwent examination using 320-row CTA with low-dose prospective electrocardiogram-triggered volume target scanning were reviewed. The coronary arteries of each infant were assessed using a 0–4-point scoring system based on the number of coronary segments with a visible course. Clinical parameters, the CT value in the ascending aorta, image noise, and the radiation dose were subjected to univariate and multivariate analyses. The mean coronary score for all examinations was 2.6?±?1.5 points. The mean attenuation in the ascending aorta was 306.7?±?66.2 HU and the mean standard deviation was 21.7?±?4.4. The mean effective radiation dose was 1.27?±?0.39 mSv. Multivariate regression analysis showed significant correlations between coronary score and body weight (p?<?0.05) and between coronary score and the CT value in the ascending aorta (p?<?0.02). Second-generation 320-row CTA with prospective electrocardiogram-triggered volume target scanning and hybrid iterative reconstruction allows good visibility of the coronary arteries in infants with complex CHD. Body weight and the CT value in the ascending aorta are important factors influencing the visibility of the coronary arteries in infants. 相似文献
44.
45.
Absorption,distribution, metabolism and excretion of novel phosphodiesterase type 4 inhibitor ASP3258 in rats 下载免费PDF全文
Yoshiaki Ohtsu Takuya Sonoda Yoko Susaki Toshifumi Tohda Yasuhisa Fukunaga Takafumi Iwatsubo Kiyoshi Noguchi 《Biopharmaceutics & drug disposition》2015,36(1):34-48
The potent and selective phosphodiesterase 4 inhibitor ASP3258 is a novel therapeutic agent for asthma and chronic obstructive pulmonary disease (COPD). After a single oral administration to rats, ASP3258 is rapidly absorbed with a bioavailability of 106%. In situ absorption data indicated that ASP3258 is mainly absorbed in the small intestine. Tissue distribution data after oral administration of 14C‐ASP3258 showed rapid and extensive distribution to various tissues. Excluding the gastrointestinal tract, the tissues with the highest concentrations were liver, heart and plasma. Liquid chromatography‐nuclear magnetic resonance spectroscopy data revealed that O‐glucuronidation of the carboxylic acid moiety of ASP3258 (formation of an acyl glucuronide) plays a key role in metabolism. No indication was found that the acyl glucuronide reacted with proteins in plasma or tissues. When 14C‐ASP3258 was orally administered to intact rats, urinary and fecal excretion accounted for 1.3% and 100.6% of the administered radioactivity, respectively. After a single oral administration of 14C‐ASP3258 to bile‐cannulated rats, urinary and biliary excretion accounted for 0.7% and 93.8% of the administered radioactivity, respectively. These findings suggest that fecal excretion via bile plays an important role in the elimination of ASP3258‐derived radioactivity. In vitro metabolic profiles were relatively similar among the species examined, suggesting that our findings in rats may help us to understand pharmacokinetics, efficacy and safety profiles in humans and other species. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
46.
Takuya Tsujimura Takayuki Ishihara Shota Okuno Osamu Iida Naoya Kurata Mitsutoshi Asai Masaharu Masuda Shin Okamoto Kiyonori Nanto Takashi Kanda Yasuhiro Matsuda Yosuke Hata Toshiaki Mano 《Journal of cardiology》2021,77(5):457-464
BackgroundPolymer-free biolimus A9-coated coronary stent (DCS) has novel features which lead to the expectation of better arterial healing. However, comparisons of intravascular status between DCS and drug-eluting stents (DES), and robust real-word clinical assessments of DCS have been lacking to date.MethodsFrom September 2017 to September 2018, we evaluated the intra-vascular status of 74 DCS implanted in 55 lesions from 43 patients using coronary angioscopy (CAS) approximately one year after implantation from a cohort of 219 lesions in 158 patients. We set 239 second-generation durable-polymer DES (DP-DES) implanted in 211 lesions from 180 patients from a cohort of 2652 lesions in 1914 patients as the control. Angioscopic images were analyzed to determine (1) the dominant degree of neointimal coverage (NIC) over the stent; (2) the heterogeneity of NIC; (3) yellow color grade of the stented segment; and (4) the presence of intra-stent thrombus. The primary outcome was the incidence of thrombus and secondary outcomes were the other CAS findings, and the 1-year clinical outcomes which included target lesion revascularization (TLR) and major adverse cardiac events (MACE). To minimize inter-group differences in baseline characteristics, propensity score matching was performed for clinical outcomes.ResultsIncidence of thrombus adhesion was similar in DCS and DP-DES groups (28.4% versus 22.6%, p = 0.31). However, the dominant NIC grade was significantly higher in DCS (p < 0.001), while NIC was more heterogeneous in DCS than in DP-DES (p = 0.001). Maximum yellow color grade was similar (p = 0.22). After propensity score matching, 202 lesion pairs from 146 patient pairs were retained for analysis. The cumulative incidence of TLR (4.6% versus 3.8%, p = 0.38) and MACE (11.6% versus 11.7%, p = 0.84) was similar for DCS and DP-DES.ConclusionsDCS showed thrombus adhesion and clinical outcomes at 1 year similar to DP-DES. DCS can thus be used with similar safety and efficacy as DP-DES. 相似文献
47.
Genda Takuya Ichida Takafumi Tanaka Eiji Mochida Satoshi Ueno Yoshiyuki Terai Shuji Inui Ayano Ueda Yoshihide Ohdan Hideki Egawa Hiroto Umeshita Koji Furukawa Hiroyuki Inomata Yukihiro 《Journal of gastroenterology》2022,57(7):495-504
Journal of Gastroenterology - Following liver transplantation (LT), allograft liver failure can be developed by various causes and requires re-LT. Hence, this study aimed to clarify the... 相似文献
48.
Takuya Satomi Seiji Kawano Tomoki Inaba Masahiro Nakagawa Hirokazu Mouri Masao Yoshioka Shoichi Tanaka Tatsuya Toyokawa Sayo Kobayashi Takehiro Tanaka Hiromitsu Kanzaki Masaya Iwamuro Yoshiro Kawahara Hiroyuki Okada 《World journal of gastroenterology : WJG》2021,27(11):1043-1054
BACKGROUNDRecent improvements in the prognosis of patients with esophageal cancer have led to the increased occurrence of gastric tube cancer (GTC) in the reconstructed gastric tube. However, there are few reports on the treatment results of endoscopic submucosal dissection (ESD) for GTC.AIMTo evaluate the efficacy and safety of ESD for GTC after esophagectomy in a multicenter trial.METHODSWe retrospectively investigated 48 GTC lesions in 38 consecutive patients with GTC in the reconstructed gastric tube after esophagectomy who had undergone ESD between January 2005 and December 2019 at 8 institutions participating in the Okayama Gut Study group. The clinical indications of ESD for early gastric cancer were similarly applied for GTC after esophagectomy. ESD specimens were evaluated in 2-mm slices according to the Japanese Classification of Gastric Carcinoma with curability assessments divided into curative and non-curative resection based on the Gastric Cancer Treatment Guidelines. Patient characteristics, treatment results, clinical course, and treatment outcomes were analyzed.RESULTSThe median age of patients was 71.5 years (range, 57-84years), and there were 34 men and 4 women. The median observation period after ESD was 884 d (range, 8-4040 d). The median procedure time was 81 min (range, 29-334 min), the en bloc resection rate was 91.7% (44/48), and the curative resection rate was 79% (38/48). Complications during ESD were seen in 4% (2/48) of case, and those after ESD were seen in 10% (5/48) of case. The survival rate at 5 years was 59.5%. During the observation period after ESD, 10 patients died of other diseases. Although there were differences in the procedure time between institutions, a multivariate analysis showed that tumor size was the only factor associated with prolonged procedure time.CONCLUSIONESD for GTC after esophagectomy was shown to be safe and effective. 相似文献
49.
Ayabe M Brubaker PH Dobrosielski D Miller HS Ishi K Yahiro T Kiyonaga A Shindo M Tanaka H 《Journal of cardiopulmonary rehabilitation》2004,24(2):80-86
PURPOSE: This investigation aimed to examine the physical activity patterns of cardiac rehabilitation program (CRP) participants. METHODS: The investigation enrolled 53 male and 24 female CRP participants between 46 and 88 years of age. By means of a uniaxial accelerometer (Life-Corder), the amount of physical activity (in kilocalories) and the time spent in physical activity at light (<3 metabolic equivalents [METs]), moderate (3 to 6 METs), and vigorous (>6 METs) intensity were evaluated. In addition to these variables, the MET levels for the CRP and non-CRP periods were calculated. RESULTS: The weekly amount of physical activity energy expenditure averaged 1597 +/- 846 kcal/week, and the time spent in light, moderate, and vigorous physical activity averaged, respectively, 375.5 +/- 124.5 minutes, 125.2 +/- 109.4 minutes, and 5.7 +/- 12.8 minutes per week. These levels were significantly lower on non-CRP days than on CRP days: 177 +/- 113 versus 299 +/- 161 kcal/day and, respectively, 49.3 +/- 19.3 versus 59.7 +/- 19.8 minutes, 10.5 +/- 14.6 versus 26.4 +/- 20.4 minutes, and 0.4 +/- 1.7 versus 1.4 +/- 3.0 minutes per day. CONCLUSIONS: These results indicate that the amount of physical activity was generally adequate on CRP days, but failed to reach target levels on non-CRP days. Thus CRP participants, when it is medically appropriate, should be encouraged to incorporate lifestyle physical activity, additional exercise, or both on non-CRP days to supplement their caloric expenditure from CRP exercise sessions. 相似文献
50.
Sugi H Minoda H Inayoshi Y Yumoto F Miyakawa T Miyauchi Y Tanokura M Akimoto T Kobayashi T Chaen S Sugiura S 《Proceedings of the National Academy of Sciences of the United States of America》2008,105(45):17396-17401
Despite >50 years of research work since the discovery of sliding filament mechanism in muscle contraction, structural details of the coupling of cyclic cross-bridge movement to ATP hydrolysis are not yet fully understood. An example would be whether lever arm tilting on the myosin filament backbone will occur in the absence of actin. The most direct way to elucidate such movement is to record ATP-induced cross-bridge movement in hydrated thick filaments. Using the hydration chamber, with which biological specimens can be kept in an aqueous environment in an electron microscope, we have succeeded in recording ATP-induced cross-bridge movement in hydrated thick filaments consisting of rabbit skeletal muscle myosin, with gold position markers attached to the cross-bridges. The position of individual cross-bridges did not change appreciably with time in the absence of ATP, indicating stability of time-averaged cross-bridge mean position. On application of ATP, individual cross-bridges moved nearly parallel to the filament long axis. The amplitude of the ATP-induced cross-bridge movement showed a peak at 5–7.5 nm. At both sides of the filament bare region, across which the cross-bridge polarity was reversed, the cross-bridges were found to move away from, but not toward, the bare region. Application of ADP produced no appreciable cross-bridge movement. Because ATP reacts rapidly with the cross-bridges (M) to form complex (M·ADP·Pi) with an average lifetime >10 s, the observed cross-bridge movement is associated with reaction, M + ATP → M·ADP·Pi. The cross-bridges were observed to return to their initial position after exhaustion of ATP. These results constitute direct demonstration of the cross-bridge recovery stroke. 相似文献