首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   21321篇
  免费   1493篇
  国内免费   481篇
耳鼻咽喉   169篇
儿科学   185篇
妇产科学   1116篇
基础医学   1868篇
口腔科学   1070篇
临床医学   1774篇
内科学   2090篇
皮肤病学   264篇
神经病学   632篇
特种医学   1157篇
外国民族医学   2篇
外科学   6813篇
综合类   2266篇
现状与发展   2篇
预防医学   801篇
眼科学   145篇
药学   993篇
  24篇
中国医学   307篇
肿瘤学   1617篇
  2024年   66篇
  2023年   550篇
  2022年   864篇
  2021年   1210篇
  2020年   1195篇
  2019年   1064篇
  2018年   909篇
  2017年   799篇
  2016年   736篇
  2015年   799篇
  2014年   1500篇
  2013年   1501篇
  2012年   1189篇
  2011年   1298篇
  2010年   1017篇
  2009年   1089篇
  2008年   1067篇
  2007年   985篇
  2006年   821篇
  2005年   719篇
  2004年   633篇
  2003年   514篇
  2002年   366篇
  2001年   325篇
  2000年   249篇
  1999年   238篇
  1998年   216篇
  1997年   171篇
  1996年   153篇
  1995年   148篇
  1994年   104篇
  1993年   85篇
  1992年   73篇
  1991年   75篇
  1990年   73篇
  1989年   45篇
  1988年   47篇
  1987年   60篇
  1986年   40篇
  1985年   54篇
  1984年   46篇
  1983年   25篇
  1982年   43篇
  1981年   36篇
  1980年   30篇
  1979年   18篇
  1978年   27篇
  1977年   6篇
  1976年   10篇
  1973年   4篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
RolesofDNApolymeraseβonrepairofDNAdamagedbyγ-raysirradiationCaiJianming(蔡建明);ZhengXiulong(郑秀龙);LuoChengji(罗成基);GaoJianguo(高建国...  相似文献   
102.
The Raz four-corner suspension for the treatment of severe (grades 3 and 4) cystocele has yielded poor results, and is the subject of this paper. During a 10-month period from June 1988 to April 1989, 27 patients with severe cystocele and genuine stress incontinence were treated by the Raz four-corner suspension. Each patient had full preoperative urodynamic evaluation. Twenty-two patients were available for follow-up examinations at 3.5–4 years. At the 6-week postoperative examination all patients had excellent support of the anterior vaginal wall, including the restoration of the anterolateral vaginal wall sulci. However, within 10 months, 6 patients had recurrence of cystoceles of grade 2 or more. These results led to the abandonment of this procedure. On long-term follow-up examination at 3.5–4 years, 59% (13/22) of the patients had recurrence of cystoceles of grade 2 or more. The possible causes for these poor results are discussed. At present therefore, the Raz four-corner suspension for severe cystoceles is not recommended.  相似文献   
103.
Vesicovaginal fistulas (VVFs) occurring as a result of obstetric trauma are a vast problem in Nigeria and Ghana, where at least 20 000 women await repair, and fewer than 50 physicians have the necessary expertise. Through a series of conferences those VVFs that are at high risk and those at low-risk for repair failure, were identified. A clinic was established where repair of low-risk VVFs was done on an ongoing basis in a remote region of Ghana. A visiting surgical team was utilized to repair the difficult, or high-risk, VVFs, which included 4–6 cm VVFs (3), recurrent VVF (1), combined VVF and RVF (rectovaginal fistula), a large 5 cm juxtacervical VVF (1), and a vesicouterine fistula (1). Management of these patients and others with VVF repair complications is discussed.  相似文献   
104.
The introduction of laparoscopic inguinal hernia repair (LIHR) has been controversial. A questionnaire was sent to all general surgeons in New Zealand to document the early experience with LIHR and attitudes towards it. Of the 118 replies (response rate 55%). 74 were from laparoscopic surgeons. 26 of whom had performed 564 (201 public. 363 private) LIHR (23 bilateral) until January 1994. Only nine (35%) of these surgeons had assisted an experienced surgeon before performing an LIHR. and only four (15%) were supervised by an experienced surgeon during their first case. The transabdominal preperitoneal technique of LIHR was used by 14 (54%) surgeons. the extraperitoneal technique by eight (31%), and the tronsabdominal onlny technique by four (15%). There were 29 (5%) recurrences, 17 (3%) neuropathies. seven (1.2%) conversions, four (0.7%) miijor perforations. and one (0.17%) death. Of the 26 surgeons who performed LIHR, 20 (77%) were concerned about the absence of long-term results. 14 (54%) considered that the optimal technique had not been established. 13 (50%) were concerned about the unique complications associated with LIHR. 11 (42%) were less enthusiastic about performing LIHR than previously. 10 (38%) were doubtful about its advantages, and six (23%,) were uncertain about its future and considered that it should only be performed within the context of a controlled trial. This study highlights a number of issues that need to be addressed before the role of LIHR can be determined.  相似文献   
105.
The SOS chromotest is a simple short-term genotoxicity assay measuring the induction of gene sfiA in Escherichia coli K-12. The recent availability of SOS tester strains with additional mutations in DNA repair or protection systems allows testing of DNA damaging compounds for genotoxic specificity. E. coli PQ300 differs from the standard SOS tester strain PQ37 in that it contains an additional mutation in gene oxyR that renders it more sensitive to oxidative genotoxins. The generation of reactive oxygen intermediates (ROI) by hydroperoxides (H2O2, t-butyl hydroperoxide, cumene hydroperoxide), gamma-radiation, glucose oxidase, and xanthine oxidase resulted in a more vigorous SOS response in strain PQ300 compared to strain PQ37. PQ300 was also more sensitive than PQ37 for the detection of reducing agents such as ascorbic acid, cysteine, and glutathione, which also alter the redox status of the bacterial cells. However, intercalating agents (adriamycin, bleomycin, and mitomycin C) and the UV- and radiomimetic compound 4-nitroquinoline-1-oxide whose DNA damaging potential are known also to involve ROI did not show significant differences between strains PQ37 and PQ300. It is concluded that the oxyR-deficient strain PQ300 is useful for detecting certain classes of genotoxins that change the oxidative/antioxidative balance of tester bacteria in the SOS chromotest.  相似文献   
106.
Eighteen patients with chronic constipation were diagnosed as having paradoxical puborectalis contraction (PPC) as the cause for their constipation. The diagnosis of PPC was made after office evaluation, colonic transit study, manometry, cinedefecography, and electromyography (EMG). These 18 patients had a mean duration of symptoms of 26.9 years; none of these patients had unassisted bowel movements. Fourteen patients had a mean of 4.6 laxative-induced bowel evacuations per week, and 11 patients had a mean of 4.4 enema-induced bowel evacuations per week. Patients underwent a mean of 8.9 one-hour EMG-based biofeedback sessions. At a mean follow-up of 9.1 (range, 0.5–12) months, these 18 patients had a mean of 7.3 unassisted bowel actions per week ( P <0.0001). In addition, persistent laxative use was reported by only two patients, and, in both cases, this was once a week or less ( P <0.001). Similarly, enema use was reported by only three patients, one once weekly and the other two thrice weekly ( P <0.002). No biofeedback-related complications were identified. EMG-based biofeedback is a valuable technique associated with an 89 percent success rate in the treatment of PPC.Read at the meeting of The American Society of Colon and Rectal Surgeons, Boston, Massachusetts, May 12 to 17, 1991.  相似文献   
107.
马显杰  夏炜  张辉  鲁开化  郭树忠  韩岩 《中国美容医学》2006,15(7):787-788,i0004
目的:探讨烧、创伤后,足背瘢痕挛缩所致仰趾畸形的治疗。方法:术中将足背瘢痕切除,彻底松解挛缩,将弓弦状伸肌腱切除部分或切断,切除部分挛缩的跖趾关节背侧关节囊,使关节复位,克氏针外固定,在拇指内侧或小趾侧,以跖趾关节处为蒂设计逆行皮瓣,转移覆盖外露的跖趾关节,供区及瘢痕切除后创面行全厚或断层皮片修复。结果:本组7例,均采用逆行皮瓣修复,畸形完全纠正,无继发畸形。结论:应用拇指及小趾侧方逆行皮瓣转移,治疗仰趾畸形可达到满意效果。  相似文献   
108.
109.
110.
Introduction: Chronic groin pain is the most common long-term complication after open inguinal hernia repair. Traditional surgical management of the associated neuralgia consists of injection therapy followed by groin exploration, mesh removal, and nerve transection. The resultant hernia defect may be difficult to repair from an anterior approach. We evaluate the outcomes of a combined laparoscopic and open approach for the treatment of chronic groin pain following open inguinal herniorrhaphy. Methods: All patients who underwent groin exploration for chronic neuralgia after a prior open inguinal hernia repair were prospectively analyzed. Patient demographics, type of prior hernia repair, and prior nonoperative therapies were recorded. The operation consisted of a standard three trocar laparoscopic transabdominal preperitoneal hernia repair, followed by groin exploration, mesh removal, and nerve transection. Outcome measures included recurrent groin pain, numbness, hernia recurrence, and complications. Results: Twelve patients (11 male and 1 female) with a mean age of 41 years (range 29–51) underwent combined laparoscopic and open treatment for chronic groin pain. Ten patients complained of unilateral neuralgia, one patient had bilateral complaints, and one patient complained of orchalgia. All patients failed at least two attempted percutaneous nerve blocks. Prior repairs included Lichtenstein (n=9), McVay (n=1), plug and patch (n=1), and Shouldice (n=1). There were no intraoperative complications or wound infections. With a minimum of 6 weeks follow up, all patients were significantly improved. One patient complained of intermittent minor discomfort that required no further therapy. Two patients had persistent numbness in the ilioinguinal nerve distribution but remained satisfied with the procedure. Conclusions: A combined laparoscopic and open approach for postherniorrhaphy groin pain results in good to excellent patient satisfaction with no perioperative morbidity. It may be the preferred technique for the definitive management of chronic neuralgia after prior open hernia repair.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号