全文获取类型
收费全文 | 50731篇 |
免费 | 2338篇 |
国内免费 | 422篇 |
专业分类
耳鼻咽喉 | 484篇 |
儿科学 | 1092篇 |
妇产科学 | 638篇 |
基础医学 | 6648篇 |
口腔科学 | 852篇 |
临床医学 | 3138篇 |
内科学 | 13013篇 |
皮肤病学 | 1218篇 |
神经病学 | 3688篇 |
特种医学 | 2066篇 |
外科学 | 8694篇 |
综合类 | 190篇 |
一般理论 | 6篇 |
预防医学 | 1345篇 |
眼科学 | 1120篇 |
药学 | 3232篇 |
中国医学 | 194篇 |
肿瘤学 | 5873篇 |
出版年
2023年 | 282篇 |
2022年 | 593篇 |
2021年 | 1044篇 |
2020年 | 557篇 |
2019年 | 753篇 |
2018年 | 1037篇 |
2017年 | 813篇 |
2016年 | 1034篇 |
2015年 | 1126篇 |
2014年 | 1406篇 |
2013年 | 1805篇 |
2012年 | 2899篇 |
2011年 | 3205篇 |
2010年 | 1805篇 |
2009年 | 1629篇 |
2008年 | 2963篇 |
2007年 | 3177篇 |
2006年 | 3196篇 |
2005年 | 3207篇 |
2004年 | 3283篇 |
2003年 | 3346篇 |
2002年 | 3299篇 |
2001年 | 725篇 |
2000年 | 643篇 |
1999年 | 735篇 |
1998年 | 848篇 |
1997年 | 719篇 |
1996年 | 662篇 |
1995年 | 549篇 |
1994年 | 487篇 |
1993年 | 526篇 |
1992年 | 467篇 |
1991年 | 437篇 |
1990年 | 380篇 |
1989年 | 408篇 |
1988年 | 413篇 |
1987年 | 331篇 |
1986年 | 284篇 |
1985年 | 280篇 |
1984年 | 236篇 |
1983年 | 186篇 |
1982年 | 162篇 |
1981年 | 187篇 |
1980年 | 152篇 |
1979年 | 154篇 |
1978年 | 158篇 |
1977年 | 114篇 |
1976年 | 100篇 |
1975年 | 85篇 |
1974年 | 80篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
961.
Ryosuke Ando Aya Tomita Kohei Watanabe Hiroshi Akima 《Clinical physiology and functional imaging》2018,38(4):566-572
We compared vasti muscle electromyograms for two knee joint angles during fatiguing tetanic contractions. Tetanic contraction of the knee extensors was evoked for 70 s by electrical stimulation of the femoral nerve at knee joint angles of 60° (extended, with 0° indicating full extension) and 110° (flexed) in eight healthy men. Surface electromyography was recorded from the vastus intermedius (VI), vastus lateralis (VL) and vastus medialis (VM) muscles. Knee extension force and M‐wave amplitudes and durations were calculated every 7 s, which were normalized by the initial value. Normalized knee extension force was decreased at the flexed knee joint angle compared with that of the extended knee joint angle (P<0·05). Decreased normalized M‐wave amplitude and increased normalized M‐wave duration of the VI were greater at the flexed knee joint angle than the extended knee joint angle (P<0·05), whereas those for the VL and VM were similar (P>0·05). These results suggest that peripheral fatigue profiles of the VI might be greater at the flexed than the extended knee joint angles, but that of VL and VM might be similar in the tested range of knee joint angles (i.e. 60°–110°) during continuous tetanic contraction induced by electrical stimulation. Therefore, greater reduction of knee extension force at the flexed knee joint angle than the extended knee joint angle may reflect fatigue development of the VI more than other quadriceps femoris components. 相似文献
962.
Hiroshi Wakabayashi Junichi Taki Anri Inaki Tomo Hiromasa Koichi Okuda Takayuki Shibutani Kazuhiro Shiba Seigo Kinuya 《Molecular imaging and biology》2018,20(4):544-550
Purpose
Ultra-high resolution single-photon emission computed tomography (SPECT) system, using multiple pinhole collimators, has been applied to the imaging of small rodents. We aimed to compare the myocardial infarction (MI) area on quantitative perfusion single-photon emission computed tomography (QPS; Cedars-Sinai Medical Center, USA) with that on high-resolution autoradiography in rat model to determine the accuracy of perfusion defect measurement by QPS.Procedures
After thoracotomy, rats (n?=?9) had their left coronary arteries occluded and reperfused before injection with 185 MBq [99mTc] methoxyisobutylisonitrile ([99mTc]MIBI) for SPECT and autoradiography. Healthy rats (n?=?28) were similarly scanned to create a normal database on which to base QPS. The MI area on SPECT images was analysed automatically by QPS software. For the autoradiography images, regions of interest for MI were set at 1 mm intervals.Results
In normal rats, [99mTc]MIBI accumulated throughout the left ventricles, and a polar map of ventricular perfusion showed the lowest and highest uptakes in the inferior (68 %?±?4 %) and anterior (92 %?±?5 %) walls, respectively. In the rat MI model, the percentage of polar map with reduced [99mTc]MIBI uptake correlated strongly with the percentage of left ventricle with MI on autoradiography (r2?=?0.90).Conclusions
QPS can quantitatively evaluate MI severity on myocardial perfusion images in rats, with comparable results to autoradiography. This widely available software could promote the development of new techniques for analysing cardiac images in small animals.963.
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
964.
Yuko Isoyama-Shirakawa Katsumasa Nakamura Madoka Abe Naonobu Kunitake Keiji Matsumoto Saiji Ohga Tomonari Sasaki Satoru Uehara Kazuhiro Okushima Yoshiyuki Shioyama Hiroshi Honda 《Journal of radiation research》2015,56(3):583-587
It has been suggested that pain control during intracavitary brachytherapy for cervical cancer is insufficient in most hospitals in Japan. Our hospital began using caudal epidural anesthesia during high-dose-rate (HDR) intracavitary brachytherapy in 2011. The purpose of the present study was to retrospectively investigate the effects of caudal epidural anesthesia during HDR intracavitary brachytherapy for cervical cancer patients. Caudal epidural anesthesia for 34 cervical cancer patients was performed during HDR intracavitary brachytherapy between October 2011 and August 2013. We used the patients'' self-reported Numeric Rating Scale (NRS) score at the first session of HDR intracavitary brachytherapy as a subjective evaluation of pain. We compared NRS scores of the patients with anesthesia with those of 30 patients who underwent HDR intracavitary brachytherapy without sacral epidural anesthesia at our hospital between May 2010 and August 2011. Caudal epidural anesthesia succeeded in 33 patients (97%), and the NRS score was recorded in 30 patients. The mean NRS score of the anesthesia group was 5.17 ± 2.97, significantly lower than that of the control group''s 6.80 ± 2.59 (P = 0.035). The caudal epidural block resulted in no side-effects. Caudal epidural anesthesia is an effective and safe anesthesia option during HDR intracavitary brachytherapy for cervical cancer. 相似文献
965.
966.
Takahiro Shoji Takehiko Tarui Takashi Igarashi Yuki Mochida Hiroyuki Morinaga Yasuhiko Miyakuni Yoshitaka Inoue Yasuhiko Kaita Hiroshi Miyauchi Yoshihiro Yamaguchi 《The Journal of emergency medicine》2018,54(4):410-418
Background
Bleeding from hemorrhagic shock can be immediately controlled by blocking the proximal part of the hemorrhagic point using either resuscitative thoracotomy for aortic cross-clamping or insertion of a large-caliber (10–14Fr) resuscitative endovascular balloon occlusion of the aorta (REBOA) device via the femoral artery. However, such methods are very invasive and have various complications. With recent progress in endovascular treatment, a low-profile REBOA device (7Fr) has been developed.Objective
The objective of this study was to report our experience of this low-profile REBOA device and to evaluate the usefulness of emergency physician?operated REBOA in life-threatening hemorrhagic shock.Methods
Ten patients with refractory hemorrhagic shock underwent REBOA using this device via the femoral artery. All REBOA procedures were performed by emergency physicians. The success rate of the insertion, vital signs, and REBOA-related complications were evaluated.Results
Median age was 54 years (interquartile range 33–78 years). The causes of hemorrhagic shock were trauma (n = 4; 1 blunt and 3 penetrating), ruptured abdominal aortic aneurysm (n = 3), and obstetric hemorrhage (n = 3). Two patients had cardiopulmonary arrest upon arrival. REBOA procedure was successful in all patients, and all became hemodynamically stable to undergo definitive interventions after REBOA. There were no REBOA-related complications. The mortality rate within 24 h and 30 days was 40%.Conclusions
This REBOA device was useful for emergency physicians in life-threatening hemorrhagic shock because of its ease in handling and low invasiveness. 相似文献967.
Takashi Kadowaki Masakazu Haneda Hiroshi Ito Kazuyo Sasaki Sonoe Hiraide Miyuki Matsukawa Makoto Ueno 《Advances in therapy》2018,35(6):817-831
Introduction
Healthy eating is a critical aspect of the prevention and management of type 2 diabetes (T2DM). Disrupted eating patterns can result in poor glucose control and increase the likelihood of diabetic complications. Teneligliptin inhibits dipeptidyl peptidase-4 activity for 24 h and suppresses postprandial hyperglycemia after all three daily meals. This interim analysis of data from the large-scale post-marketing surveillance of teneligliptin (RUBY) in Japan examined eating patterns and their relationship with metabolic parameters and diabetic complications. We also examined whether eating patterns affected safety and efficacy of teneligliptin.Methods
We analyzed baseline data from survey forms collected in RUBY between May 2013 and June 2017, including patient characteristics, metabolic parameters, and eating patterns (eating three meals per day or not; timing of evening meal) before teneligliptin treatment was initiated. Safety and efficacy of 12 months’ teneligliptin (20–40 mg/day) treatment was assessed.Results
Data from 10,532 patients were available for analysis. Most patients who did not eat three meals per day (n??=757) or who ate their evening meal after 10 PM (n??=206) were 64 years old or younger. At baseline, glycated hemoglobin (HbA1c), fasting blood glucose, triglycerides, total and low-density lipoprotein cholesterol, body mass index, alanine aminotransferase, and aspartate aminotransferase levels were higher in those patients who did not eat three meals per day (p?<?0.05) or who ate their evening meal late (p?<?0.05). Diabetic complications were more common in patients who did not eat three meals per day. Treatment with teneligliptin reduced HbA1c over 6 or 12 months across all eating patterns, with a low incidence of adverse drug reactions.Conclusions
Eating patterns may be associated with altered metabolic parameters and diabetic complications among Japanese patients with T2DM. Teneligliptin may be well tolerated and improve hyperglycemia in patients with T2DM irrespective of eating patterns.Funding
Mitsubishi Tanabe Pharma Corporation and Daiichi Sankyo Co. Ltd.Trial Registration Number
Japic CTI-153047.968.
969.
970.