全文获取类型
收费全文 | 8983篇 |
免费 | 392篇 |
国内免费 | 187篇 |
专业分类
耳鼻咽喉 | 59篇 |
儿科学 | 150篇 |
妇产科学 | 34篇 |
基础医学 | 591篇 |
口腔科学 | 54篇 |
临床医学 | 709篇 |
内科学 | 951篇 |
皮肤病学 | 70篇 |
神经病学 | 235篇 |
特种医学 | 245篇 |
外国民族医学 | 1篇 |
外科学 | 3537篇 |
综合类 | 1053篇 |
现状与发展 | 1篇 |
预防医学 | 846篇 |
眼科学 | 99篇 |
药学 | 390篇 |
8篇 | |
中国医学 | 264篇 |
肿瘤学 | 265篇 |
出版年
2024年 | 11篇 |
2023年 | 160篇 |
2022年 | 328篇 |
2021年 | 332篇 |
2020年 | 281篇 |
2019年 | 311篇 |
2018年 | 296篇 |
2017年 | 261篇 |
2016年 | 257篇 |
2015年 | 281篇 |
2014年 | 635篇 |
2013年 | 713篇 |
2012年 | 580篇 |
2011年 | 601篇 |
2010年 | 446篇 |
2009年 | 444篇 |
2008年 | 426篇 |
2007年 | 365篇 |
2006年 | 314篇 |
2005年 | 288篇 |
2004年 | 259篇 |
2003年 | 230篇 |
2002年 | 199篇 |
2001年 | 173篇 |
2000年 | 163篇 |
1999年 | 151篇 |
1998年 | 113篇 |
1997年 | 77篇 |
1996年 | 72篇 |
1995年 | 94篇 |
1994年 | 73篇 |
1993年 | 37篇 |
1992年 | 49篇 |
1991年 | 33篇 |
1990年 | 40篇 |
1989年 | 40篇 |
1988年 | 37篇 |
1987年 | 40篇 |
1986年 | 38篇 |
1985年 | 59篇 |
1984年 | 64篇 |
1983年 | 23篇 |
1982年 | 37篇 |
1981年 | 32篇 |
1980年 | 28篇 |
1979年 | 23篇 |
1978年 | 17篇 |
1977年 | 16篇 |
1976年 | 9篇 |
1971年 | 2篇 |
排序方式: 共有9562条查询结果,搜索用时 265 毫秒
991.
Objective To study the combination of trans-anal intersphincteric resection and trans- abdominal total mesorectal excision for anus-retained ultra-low rectal tumors. Methods Clinical data of 34 ultra-low rectal tumor patients without external anal sphincter involved, who underwent the combination surgery, were retrospectively analyzed Results The distance from the distal incisal margin of the rectum to the inferior margin of the tumor ranged from 1.8 cm to 3.0 cm on an average of 2. 1 cm. For pathological types, there were 23 cases of adenocarcinoma (9 well differentiated and 14 moderately differentiated), 1 papillary carcinoma, 2 rectal stromal tumor, 5 rectal villous adenoma with canceration and 3 giant villous adenoma. For pathological stages, there were 18 eases at stage pTNM Ⅰ , 5 at Ⅱ A, 1 at Ⅱ B, 4 at ⅢA, 1 at ⅢB and for T grading, there were 15 cases at stage T1, 5 at T2, 8 at T3, 1 at T4. In these 34 patients, there were 3 cases with postoperative anastomotic stenosis, 2 with postoperative anastomotic rupture, 2 with rectovaginal fistula and no operative death. Because of the dysfunction of bowel control, bowel frequency varied from 3 to 12 in the early stage after operation, but with the recovery of anus function, bowel frequency decreased and ranged form 1 to 5 times a day and the time of formed bowel control could be more than 5 min in 6-12 months after operation. However, patients underwent total resection of internal anal sphincter still suffered from incontinence of loose stool after 1 year. After operation, anastomotic recurrence was found in 1 case in 5 months, liver metastasis in 1 case in 10 months and 28 months respectively, cardiac sudden death in 1 case in 26 months. Conclusion The combination of trans-anal ISR and trans-abdominal TME for anus-retained ultra low rectal tumor is not only coincident with radical tumor principle but also retains the function of anus, on the premise of the strict indication. 相似文献
992.
Gastric pull-up with cervical oesophagogastric anastomosis is a common procedure after oesophageal resection. Contrast studies are used by many surgeons for detection of anastomotic leaks but may be unnecessary. A prospective study was undertaken to compare gastrografin study and test feeding using water for detection of cervical anastomotic leaks. In 25 patients. gastrografin study showed three leaks, two of which were clinically silent and patients did not have any problems. One patient had aspiration of contrast and the study could not be completed. Two of the leaks detected clinically were missed by contrast study (one because of an incomplete study and the other was a satisfactory study). Delayed leaks occurred in two patients. All leaks healed spontaneously. A contrast study may thus be unnecessary for evaluation of a cervical oesophagogastric anastomosis and can be replaced with the simpler and safer technique of ‘test feeding’ using water. 相似文献
993.
Postoperative and long-term results of ileal pouch-anal anastomosis for ulcerative colitis and familial polyposis coli 总被引:6,自引:0,他引:6
Salemans J. M. J. I. Nagengast F. M. Lubbers E. J. C. Kuijpers J. H. 《Digestive diseases and sciences》1992,37(12):1882-1889
The immediate postoperative and long-term functional results of 51 ulcerative colitis patients and 21 familial polyposis patients who underwent ileal J-pouch-anal anastomosis were compared in this study. The incidence of postoperative complications requiring reoperation was not statistically different in both groups. The mean daily stool frequency was significantly higher in colitis patients. Pouchitis occurred in 44% of colitis patients but not in polyposis patients (P<0.005). Symptoms of pouchitis included bloody diarrhea, urgency, abdominal pain, weight loss, fever, and arthritis. Six colitis patients required pouch excision because of intractable pouchitis. The overall pouch excision rate was 22% in ulcerative colitis patients and 5% in familial polyposis patients. Patient satisfaction was good in 46% of ulcerative colitis patients and 76% of polyposis patients (P<0.05). Our data demonstrate that the long-term outcome of ileal pouch-anal anastomosis is more favorable in polyposis patients than in colitis patients. Pouchitis is a major long-term complication occurring exclusively in colitis patients. 相似文献
994.
Primary infra-inguinal arterial reconstructions were reviewed for primary patency and outcome of thrombosis in 144 patients. Distal anastomoses in these patients were to the popliteal artery and were above the knee in 63, below the knee in 53 and at the tibial level in 28. The treatment used was: polytetrafluoroethylene (PTFE) in 33 cases, PTFE with an interposition vein cuff in 29 cases, autogenous saphenous vein (ASV) in situ in 47 cases, and reversed technique in 26 cases. Life table analysis showed a 59% overall primary patency at 3 years. Patency rates of above knee anastomoses (65%) and below knee (61%) were statistically different from the tibial anastomoses (42%. P = 0.005). In both above and below knee popliteal anastomoses there was a statistically significant difference in the patency of ASV and the PTFE/vein cuff technique (P= 0.0006) but there was no difference between ASV and FTFE. There was no difference in patency rates for the various types of grafts with tibial anastomoses. Data were analysed at 3 years, taking into account the variables of smoking, diabetes or indications for surgery respectively and no difference was found in patency. The number and calibre of the run-off vessels did not influence patency significantly, hence anastomosis to any good quality vessel regardless of run-off is recommended. The poor results with the interposition vein cuff technique are unexplained but this study suggests that the technique should he reserved for anastomoses below the popliteal artery. 相似文献
995.
Masato Kusunoki Yasutsugu Shoji Hidenori Yanagi Youichirou Sakanoue Takehira Yamamura Joji Utsunomiya 《Surgery today》1992,22(1):91-92
A thread holding ring, originally developed for valve replacement surgery and now commercially available, was successfully employed when performing ileoanal or coloanal anastomosis in 34 patients. The use of this instrument for ileoanal or coloanal anastomosis shortened the operation time and resulted in a decreased rate of complications related to the anastomosis. 相似文献
996.
A total of 102 matched hand radiographs were taken by digital luminescent radiography (DLR) and conventional) screen film system combinations. In DLR two differently postprocessed images were obtained from each data set: A display with low-spatial frequency enhancement filtered to took like a conventional radiograph was placed opposite a display with high-edge enhancement. Conventional and digital images were evaluated rank only and separately by four radiologists, using a questionnaire. Using DLR proved diagnostically equivalent to the conventional technique except for a diminished visibility of subtle erosions and fissures. High-frequency enhancement did not provide additional diagnostic information and led to artifacts at the edges of metal prostheses. Densitometry confirmed an optimized density of digital radiographs. The main argument for the employment of digital techniques is the availability of data for picture archiving and communications systems. 相似文献
997.
Objective To study the combination of trans-anal intersphincteric resection and trans- abdominal total mesorectal excision for anus-retained ultra-low rectal tumors. Methods Clinical data of 34 ultra-low rectal tumor patients without external anal sphincter involved, who underwent the combination surgery, were retrospectively analyzed Results The distance from the distal incisal margin of the rectum to the inferior margin of the tumor ranged from 1.8 cm to 3.0 cm on an average of 2. 1 cm. For pathological types, there were 23 cases of adenocarcinoma (9 well differentiated and 14 moderately differentiated), 1 papillary carcinoma, 2 rectal stromal tumor, 5 rectal villous adenoma with canceration and 3 giant villous adenoma. For pathological stages, there were 18 eases at stage pTNM Ⅰ , 5 at Ⅱ A, 1 at Ⅱ B, 4 at ⅢA, 1 at ⅢB and for T grading, there were 15 cases at stage T1, 5 at T2, 8 at T3, 1 at T4. In these 34 patients, there were 3 cases with postoperative anastomotic stenosis, 2 with postoperative anastomotic rupture, 2 with rectovaginal fistula and no operative death. Because of the dysfunction of bowel control, bowel frequency varied from 3 to 12 in the early stage after operation, but with the recovery of anus function, bowel frequency decreased and ranged form 1 to 5 times a day and the time of formed bowel control could be more than 5 min in 6-12 months after operation. However, patients underwent total resection of internal anal sphincter still suffered from incontinence of loose stool after 1 year. After operation, anastomotic recurrence was found in 1 case in 5 months, liver metastasis in 1 case in 10 months and 28 months respectively, cardiac sudden death in 1 case in 26 months. Conclusion The combination of trans-anal ISR and trans-abdominal TME for anus-retained ultra low rectal tumor is not only coincident with radical tumor principle but also retains the function of anus, on the premise of the strict indication. 相似文献
998.
目的分析术中结肠灌洗在急性梗阻性左半结肠癌一期切除吻合的临床疗效。方法回顾性分析2000年1月至2003年12月间经我院手术治疗的急性梗阻性左半结肠癌一期切除吻合的16名患者的临床资料。结果16例患者中切口感染1例。无1例出现吻合口瘘。结论正确的评估及术前、术中及术后的正确处理,经术中结肠灌洗后,急性梗阻性左半结肠癌行一期切除吻合是安全可行的。 相似文献
999.
In coronary artery bypass graft (CABG) surgery the involved tissues are overstretched, which may lead to intimal hyperplasia
and graft failure. We propose a computational methodology for the simulation of traditional CABG surgery, and analyze the
effect of two clinically relevant parameters on the artery and graft responses, i.e., incision length and insertion angle
for a given graft diameter. The computational structural analyses are based on actual three-dimensional vessel dimensions
of a human coronary artery and a human saphenous vein. The analyses consider the structure of the end-to-side anastomosis,
the residual stresses and the typical anisotropic and nonlinear vessel behaviors. The coronary artery is modeled as a three-layer
thick-walled tube. The finite element method is employed to predict deformation and stress distribution at various stages
of CABG surgery. Small variations of the arterial incision have relatively big effects on the size of the arterial opening,
which depends solely on the residual stress state. The incision length has a critical influence on the graft shape and the
stress in the graft wall. Stresses at the heel region are higher than those at the toe region. The changes in the mechanical
environment are severe along all transitions between the venous tissue and the host artery. Particular stress concentrations
occur at the incision ends. The proposed computational methodology may be useful in designing a coronary anastomotic device
for reducing surgical trauma. It may improve the quantitative knowledge of vessel diseases and serve as a tool for virtual
planning of vascular surgery. 相似文献
1000.