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   1156篇
  免费   114篇
  国内免费   74篇
耳鼻咽喉   16篇
儿科学   14篇
妇产科学   33篇
基础医学   37篇
口腔科学   21篇
临床医学   192篇
内科学   385篇
皮肤病学   19篇
神经病学   5篇
特种医学   56篇
外科学   222篇
综合类   197篇
现状与发展   1篇
预防医学   28篇
眼科学   1篇
药学   48篇
  3篇
中国医学   8篇
肿瘤学   58篇
  2024年   2篇
  2023年   32篇
  2022年   62篇
  2021年   99篇
  2020年   90篇
  2019年   41篇
  2018年   43篇
  2017年   36篇
  2016年   67篇
  2015年   56篇
  2014年   81篇
  2013年   83篇
  2012年   61篇
  2011年   77篇
  2010年   65篇
  2009年   51篇
  2008年   42篇
  2007年   30篇
  2006年   34篇
  2005年   29篇
  2004年   32篇
  2003年   23篇
  2002年   23篇
  2001年   19篇
  2000年   13篇
  1999年   18篇
  1998年   12篇
  1997年   12篇
  1996年   23篇
  1995年   10篇
  1994年   9篇
  1993年   12篇
  1992年   7篇
  1991年   12篇
  1990年   12篇
  1989年   7篇
  1988年   3篇
  1987年   3篇
  1986年   4篇
  1985年   3篇
  1984年   3篇
  1982年   1篇
  1980年   1篇
  1979年   1篇
排序方式: 共有1344条查询结果,搜索用时 15 毫秒
1.

Background

The efficacy of dexamethasone in extending the duration of local anaesthetic block is uncertain. In a randomised controlled triple blind crossover study in volunteers, we tested the hypothesis that neither i.v. nor perineurally administered dexamethasone prolongs the sensory block achieved with ropivacaine.

Methods

Ultrasound-guided ulnar nerve blocks (ropivacaine 0.75% wt/vol, 3 ml, with saline 1 ml with or without dexamethasone 4 mg) were performed on three occasions in 24 male volunteers along with an i.v. injection of saline 1 ml with or without dexamethasone 4 mg. The combinations of saline and dexamethasone were as follows: control group, perineural and i.v. saline; perineural group, perineural dexamethasone and i.v. saline; i.v. group, perineural saline and i.v. dexamethasone. Sensory block was measured using a VAS in response to pinprick testing. The duration of sensory block was the primary outcome and time to onset of sensory block the secondary outcome.

Results

All 24 subjects completed the trial. The median [inter-quartile range (IQR)] duration of sensory block was 6.87 (5.85–7.62) h in the control group, 7.37 (5.78–7.93) h in the perineural group and 7.37 (6.10–7.97) h in the i.v. group (P=0.61). There was also no significant difference in block onset time between the three groups.

Conclusion

Dexamethasone 4 mg has no clinically relevant effect on the duration of sensory block provided by ropivacaine applied to the ulnar nerve.

Clinical trial registration

DRKS, 00014604; EudraCT, 2018-001221-98.  相似文献   
2.
Symptomatic liver cyst: Special reference to surgical management   总被引:2,自引:0,他引:2  
We conducted a retrospective study of 14 patients with symptomatic liver cysts to evaluate current therapeutic interventions for this condition. Abdominal pain (n = 7) or abdominal mass (n = 5) were the most frequent presentations. Three patients also had renal cyst. Percutaneous aspiration with ethanol sclerotheraphy was carried out in 4 patients and all cysts so treated diminished in size, with relief of the symptoms. One patient was treated by aspiration only and re-retension occurred. Cystectomy was performed in 2 patients, unroofing in 5, and fenestration in 2 patients. All patients gained relief of symptoms, with no recurrence of symptoms. Computed tomography revealed that the cysts were diminished or were no longer observable after all the treatments. Our experience indicates that unroofing, fenestration, and cystectomy are safe and suitable procedures for treatment of the condition. Ethanol sclerotherapy may be a feasible alternative to surgical intervention in selected patients. Received for publication on July 23, 1997; accepted on Dec. 25, 1997  相似文献   
3.
Background: Symptomatic testicular hydrocele and cyst of the epididymis may be treated with either operation or sclerotherapy. Methods: The current report presents the experience of a 9 year prospective study using sodium tetradecyl sulphate (STD) sclerotherapy for the treatment of symptomatic hydrocele and/or epididymal cyst. Results: A total of 102 lesions were treated during the study period, with an initial success rate of 76% which improved to 94% with multiple treatments. The overall median follow up during the study was 30 months (range 2–100). Conclusions: Sclerotherapy offers a cost-effective outpatient method for the treatment of symptomatic scrotal cysts.  相似文献   
4.
经内镜注射5%鱼肝油酸钠治疗食管静脉曲张15例,共注射45次。其肝功能按Child分级,A级1例,B级8例,C级6例。曾经作过脾切除,分流或断流术者7例。8例急症出血患者经用硬化疗法获得了止血成功。1例急症患者死亡。6例作了择期预防出血的注射,治疗后均得到改善。治疗出血方面,硬化疗法在15例患者中14例有效,随访6~12月无再出血。  相似文献   
5.
Nineteen patients with 49 symptomatic non-neoplastic non-parasitic simple hepatic cysts were subjected to ultrasonographically guided percutaneous aspiration and temporary injection of 99% ethanol into the cyst. Small cysts were treated twice, the large ones three times at the same sitting. The volume of alcohol per injection varied from 20 to 100 ml, depending on the size of the cyst. A cure was usually achieved with one ethanol sclerotherapy treatment. Only minor side effects such as transient pain and temperature elevation occurred. Forty-seven of the 49 cysts could be treated adequately, and did not recur during a follow-up period af 12–40 months. The results indicate that aspiration an and ethanol sclerotherapy is the treatment of choice in patients with symptomatic non-neoplastic simple hepatic cysts or polycystic liver disease. Correspondence to: A. Leinonen  相似文献   
6.
Technique and early clinical results of endoscopic variceal ligation (EVL)   总被引:5,自引:0,他引:5  
Summary Endoscopic variceal ligation (EVL) is a new technique designed to be used instead of sclerotherapy. Small elastic O rings ligate varices resulting in their strangulation and eradication. During a 12-month period, EVL was employed in 53 consecutive patients, of whom 36 (68%) had alcoholic cirrhosis 17 were Child-Pugh class A, 22 class B, and 14 class C. Varices were graded from I to IV and repeat treatments were given at 1–2 week intervals until the varices were eliminated. At follow-up ranging from 6–18 months (mean 11.5), 217 EVL treatment sessions had been performed. Of the 13 patients (24%) who died during the study, 11 died during the index hospitalization. Active bleeding was controlled in 19 of 21 patients (90%). Of 40 survivors 13 patients (33%) had 1–2 (mean 1.4) recurrent variceal bleeds while 34 patients had repeat EVL treatment. Elimination of distal varices was achieved in 26 and 7 had reduction of varices from grade III–IV to grade I–II or less. Eradication required a mean of 4.4 EVL sessions in Child's A and B patients and 7.0 sessions in Child's C patients (P<0.025). No significant treatment-related complications were observed. EVL appears to control active bleeding, is associated with a low incidence of non-bleeding complications, and may be used as an alternative to sclerotherapy.  相似文献   
7.
Between October 1998 and January 1999, we examined the influence of ultrasound guidance in embryo transfer on pregnancy rate in 362 patients from our in-vitro fertilization (IVF)-embryo transfer programme. These patients were prospectively randomized into two groups: 182 had ultrasound-guided embryo replacement, and 180 had clinical touch embryo transfer. There were no statistically significant differences between the two groups with respect to age, cause of infertility and in the characteristics of the IVF cycle. The pregnancy rate was significantly higher among the ultrasound-guided embryo transfer group (50%) compared with the clinical touch group (33.7%) (P < 0.002). Furthermore, there was also a significant increase in the implantation rate: 25.3% in the ultrasound group compared with 18.1% in the clinical touch group (P < 0.05). In conclusion, ultrasound assistance in embryo transfer significantly improved pregnancy and implantation rates in IVF.  相似文献   
8.
The learning curve for novices developing regional anaesthesia skills, such as real-time ultrasound-guided needle manipulation, may be affected by innate visuospatial ability, as this influences spatial cognition and motor co-ordination. We conducted a multinational randomised controlled trial to test if novices with low visuospatial ability would perform better at an ultrasound-guided needling task with deliberate practice training than with discovery learning. Visuospatial ability was evaluated using the mental rotations test-A. We recruited 140 medical students and randomly allocated them into low-ability control (discovery learning), low-ability intervention (received deliberate practice), high-ability control, and high-ability intervention groups. Primary outcome was the time taken to complete the needling task, and there was no significant difference between groups: median (IQR [range]) low-ability control 125 s (69–237 [43–600 s]); low-ability intervention 163 s (116–276 [44–600 s]); high-ability control 130 s (80–210 [41–384 s]); and high-ability intervention 177 s (113–285 [43–547 s]), p = 0.06. No difference was found using the global rating scale: mean (95%CI) low-ability control 53% (95%CI 46–60%); low-ability intervention 61% (95%CI 53–68%); high-ability control 63% (95%CI 56–70%); and high-ability intervention 66% (95%CI 60–72%), p = 0.05. For overall procedure pass/fail, the low-ability control group pass rate of 42% (14/33) was significantly less than the other three groups: low-ability intervention 69% (25/36); high-ability control 68% (25/37); and high-ability intervention 85% (29/34) p = 0.003. Further research is required to determine the role of visuospatial ability screening in training for ultrasound-guided needle skills.  相似文献   
9.
Background:Urosepsis is a recognized complication of transrectal ultrasound-guided prostate biopsy (TRUS-Bx). Pre-biopsy rectal swabs have been used to identify patients with microorganisms in the rectal flora resistant to the conventionally used empirical prophylaxis. The transperineal route of biopsy (TP-Bx) has a lower complication risk but comes at an increased cost.Materials and methods:Retrospective cohort study including patients undergoing prostate biopsies between October/2015 and April/2018. The intervention cohort, a rectal swab was performed, the result of which dictated the biopsy route; TRUS-Bx against TP-Bx. TP-Bx for patients with fluoroquinolone resistance or extended-spectrum β-lactamase. The control cohort underwent TRUS without a rectal swab receiving empirical antibiotics—oral ciprofloxacin and intravenous gentamicin.Results:Total 1000 patients were included in which 500 underwent a swab, 14 (2.8%) developed post-TRUS biopsy infective complications with 3 having positive bacteremia (0.6%); 500 had no swab, 47 (9.4%) developed post-TRUS biopsy infective complications with 22 (4.4%, p < 0.05) having positive bacteremia. Three patients (0.6%) of patients who underwent swab developed urinary tract infection symptoms whilst 12 (2.4%) had urinary tract infection in the control group. In those patients that underwent a swab, 14 required hospitalization with mean length of stay of 2.5 days versus 43 patients of the control with 3.6 days. Cost analysis concluded savings of this strategy was £18,711.Conclusions:We have demonstrated a protocol that reserves template biopsies for higher risk patients and can significantly reduce sepsis and other infectious complication rates whilst also proving to be a cost-efficient strategy. We recommend that units not utilizing rectal swabs to uncover the fluoroquinolone resistance rate by introducing them. We advocate units that already utilize rectal swabs, to introduce transperineal biopsy for their higher risk patients.  相似文献   
10.
哈楠林 《河北医学》2000,6(3):211-213
目的:介绍新的更有效的内痔注射方式。方法:用多普勒血流仪引导注射治疗内痔出血与脱出,与单纯注射治疗对照观察。结果:一年后出血复发率治疗组为10%,对照组为119.17%(P〈0.05);内痔脱出复发率治疗组为18.25%,对照组为25%。结论:用多普勒血流仪引导注射治疗内痔能更有效的闭塞痔动脉。  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