全文获取类型
收费全文 | 5074篇 |
免费 | 273篇 |
国内免费 | 26篇 |
专业分类
耳鼻咽喉 | 31篇 |
儿科学 | 191篇 |
妇产科学 | 28篇 |
基础医学 | 661篇 |
口腔科学 | 104篇 |
临床医学 | 300篇 |
内科学 | 1452篇 |
皮肤病学 | 149篇 |
神经病学 | 320篇 |
特种医学 | 142篇 |
外科学 | 749篇 |
综合类 | 14篇 |
预防医学 | 137篇 |
眼科学 | 215篇 |
药学 | 492篇 |
中国医学 | 10篇 |
肿瘤学 | 378篇 |
出版年
2023年 | 37篇 |
2022年 | 85篇 |
2021年 | 103篇 |
2020年 | 67篇 |
2019年 | 82篇 |
2018年 | 102篇 |
2017年 | 79篇 |
2016年 | 99篇 |
2015年 | 123篇 |
2014年 | 145篇 |
2013年 | 156篇 |
2012年 | 243篇 |
2011年 | 249篇 |
2010年 | 150篇 |
2009年 | 126篇 |
2008年 | 241篇 |
2007年 | 253篇 |
2006年 | 243篇 |
2005年 | 207篇 |
2004年 | 234篇 |
2003年 | 199篇 |
2002年 | 221篇 |
2001年 | 150篇 |
2000年 | 141篇 |
1999年 | 149篇 |
1998年 | 62篇 |
1997年 | 54篇 |
1996年 | 48篇 |
1995年 | 40篇 |
1994年 | 37篇 |
1993年 | 37篇 |
1992年 | 102篇 |
1991年 | 105篇 |
1990年 | 82篇 |
1989年 | 88篇 |
1988年 | 87篇 |
1987年 | 85篇 |
1986年 | 88篇 |
1985年 | 85篇 |
1984年 | 45篇 |
1983年 | 56篇 |
1982年 | 26篇 |
1979年 | 33篇 |
1978年 | 23篇 |
1977年 | 35篇 |
1976年 | 22篇 |
1974年 | 23篇 |
1973年 | 23篇 |
1972年 | 35篇 |
1971年 | 26篇 |
排序方式: 共有5373条查询结果,搜索用时 0 毫秒
1.
2.
3.
There is increasing evidence from human and experimental studies that the most important factor governing the outcome in head injury is the severity of diffuse axonal injuries. The authors have experienced 18 cases of severe diffuse axonal injury which showed post-traumatic coma for more than 24 hours and CT findings resembling those of shearing injuries of the cerebral white matter such as have been presented by Zimmerman et al. (1978). The consciousness levels on admission were 6 or less on the Glasgow Coma Scale and all cases were shown clinically to have primary brain stem injury. The main type of head trauma resulted from road traffic accidents (83%). Skull fractures were found in only 5 cases (28%). These findings suggested that acceleration/deceleration injury produce in the patients severe diffuse axonal injury. Initial ICP was below 20 mmHg in 11 cases out of 13 (85%). Parenchymal small hemorrhagic lesions of initial CT were basal ganglia (7 cases), corpus callosum (4 cases), pons (4 cases), midbrain (3 cases) and thalamus (2 cases). Extraparenchymal hemorrhagic lesions included intraventricular hemorrhage (6 cases) and subarachnoid hemorrhage (6 cases). Two autopsied cases of severe diffuse axonal injury (acute case and chronic case) showed remarkable congestion and edema in the deep part of the frontal white matter. Microscopic examination revealed marked axonal degeneration including axonal retraction ball in the corpus callosum, in the internal capsule and in the white matter of the brain stem. Glasgow Outcome Scale of the 18 patients at 3 months after the trauma made us concerned that no patients indicated good recovery or even only moderate disability.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
4.
5.
Takuro Yoshikawa Yasuyuki Suzuki Yasuhiro Fujino Keitaro Kakinoki Shiri Li Tadahiro Goto Tomohiro Tanaka Ippei Matsumoto Tetsuya Sakai Yasuki Tanioka Hiroshi Yokozaki Yoshikazu Kuroda 《American journal of transplantation》2005,5(9):2135-2142
Small bowel transplantation (SBT) is associated with a high incidence of infectious complications because of ischemia/reperfusion (I/R) mucosal injury concomitant with potent immunosuppression. In this study, we evaluated whether the cavitary two-layer method (cTLM) could reduce I/R injury and allow early mucosal restoration, particularly after prolonged preservation and transplantation. Canine heterotopic segmental SBT was performed immediately without preservation (group 1), after 24-h preservation in UW solution (group 2) or by the cTLM (group 3). The graft samples were taken 1 h after reperfusion and on days 1, 4 and 7. We assessed graft mucosa with detailed microscopic and electromicroscopic analyses. In Group 3, histological injury and cell apoptosis after transplantation were significantly alleviated and rapidly recovered to a similar level of group 1. The mucosal restoration was morphologically completed within 4 days. In contrast, in group 2, more pronounced mucosal injury and delayed recovery were noted. Crypt cell proliferation activity was well maintained in groups 1 and 3 throughout the experimental period. Our ultrastructural analysis suggested that mitochondrial integrity achieved by the cTLM was a basal mechanism under the prompt mucosal restoration. The cTLM could reduce I/R injury, facilitate mucosal regeneration and restore the nearly normal structure early after SBT. 相似文献
6.
Hiromi Kataoka Takashi Joh Yusuke Inoue Naotaka Ogasawara Tadayuki Oshima Satoshi Tanida Makoto Sasaki Haruhisa Nakao Takahiro Nakazawa Hirotaka Ohara 《Digestive endoscopy》2006,18(4):294-297
A 75‐year‐old male was admitted to the gastroenterology unit of Nagoya City University Hospital due to epigastralgia after surgical treatment for right renal cancer. Endoscopy revealed advanced type 1 gastric cancer in the corpus of the stomach and multiple polypoid lesions in the stomach and duodenum. X‐ray examination of the small intestine using barium showed multiple polyps in the upper jejunum. Faint pigmentation on the palm was also detected. Peutz‐Jeghers syndrome (PJS) was diagnosed, despite a lack of family history. Total gastrectomy, resection of part of the upper jejunum and intraoperative endoscopic polypectomy of duodenal polyps was performed. This is the second reported case of PJS associated with renal cancer. We also detected a missense mutation in the tumor suppressor gene STK11 that, when mutated, is causative for PJS. 相似文献
7.
8.
László Prónai Hiroe Nakazawa Kohji Ichimori Yoshinori Saigusa Tomoichi Ohkubo Kazuko Hiramatsu Shigeru Arimori János Fehér 《Inflammation》1992,16(5):437-450
This study was performed to examine the pattern of Superoxide (O
2
–
·) generation from leukocytes using the O
2
–
· specific chemiluminescence (CL) method.Cypridina luciferin analog, 2-methyl-6-(p-methoxyphenyl)-3,7-dihydroimidazo[1,2-alpha]pyrazin-3-one (MCLA) was used as a CL probe. The appropriate conditions of the MCLA method was first determined for the evaluation of the time course of O
2
–
· generation by leukocytes. The time course of O
2
–
· generation obtained by the MCLA-CL system was compared with that by the luminol-dependent CL, electron spin resonance (ESR)/spin trapping, and cytochromec systems. Following stimulation by three different stimulants (PMA, OZ, FMLP), leukocytes continuously generated O
2
–
· for up to 5 h in the MCLA-CL system, irrespective of the kind of stimulation. The curves obtained by generation ceased more rapidly in the luminol-CL, ESR/spin trapping, and cytochromec systems. A 50% activity of the initial value was observed at 70 min in the MCLA-CL system, but 30, 10 and 35 min in the other systems, respectively. The CL or O
2
–
· generation value decreased to less than 1% (possible termination) at 300, 90, 120 and 180 min, respectively. With the exception of ESR studies with OZ, the cell viability was not significantly affected in any of the trials. These results indicate that leukocytes can generate O
2
–
· much longer than previously estimated and that the MCLA-CL-system is the most suitable system for the measurement of the O
2
–
· generation by leukocytes. 相似文献
9.
10.
K Sekizawa Y Ujie H Nakazawa H Sasaki U Katsumata R Takasugi 《Nihon Ronen Igakkai zasshi. Japanese journal of geriatrics》1991,28(3):308-310
Enzymes degrading peptides may participate in the regulation of the cough reflex. Thus, decreases in enzyme activities may enhance cough reflex and a decrease in cough reflex may lead to aspiration pneumonia. Down- and up-regulation of cough reflex is important for the understanding of cough reflex. 相似文献