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   403篇
  免费   29篇
儿科学   20篇
妇产科学   2篇
基础医学   36篇
口腔科学   13篇
临床医学   39篇
内科学   111篇
皮肤病学   9篇
神经病学   19篇
特种医学   22篇
外科学   79篇
预防医学   26篇
眼科学   12篇
药学   17篇
中国医学   1篇
肿瘤学   26篇
  2024年   2篇
  2023年   15篇
  2022年   13篇
  2021年   43篇
  2020年   16篇
  2019年   16篇
  2018年   23篇
  2017年   13篇
  2016年   9篇
  2015年   10篇
  2014年   17篇
  2013年   30篇
  2012年   43篇
  2011年   29篇
  2010年   20篇
  2009年   13篇
  2008年   15篇
  2007年   18篇
  2006年   8篇
  2005年   11篇
  2004年   8篇
  2003年   4篇
  2002年   7篇
  2001年   8篇
  2000年   6篇
  1999年   2篇
  1998年   3篇
  1997年   1篇
  1996年   1篇
  1995年   1篇
  1993年   1篇
  1992年   4篇
  1991年   1篇
  1990年   1篇
  1988年   1篇
  1987年   2篇
  1986年   2篇
  1985年   6篇
  1984年   2篇
  1983年   2篇
  1982年   1篇
  1980年   1篇
  1979年   1篇
  1976年   1篇
  1975年   1篇
排序方式: 共有432条查询结果,搜索用时 15 毫秒
21.
Deep neuromuscular block aims to improve operative conditions during laparoscopic surgery with a lower intra-abdominal pressure. Studies are conflicting on whether meaningful improvements in quality of recovery occur beyond emergence, and whether lower intra-abdominal pressure is achieved. In this pragmatic randomised trial with 1:1 allocation, adults undergoing elective laparoscopic surgery were allocated to moderate neuromuscular block reversed with neostigmine, or deep neuromuscular block reversed with sugammadex. Allocation was revealed to the anaesthetist only. Primary outcome was cognitive recovery of the Postoperative Quality of Recovery Scale, 7 days after surgery. Secondary outcomes included recovery in other domains of the Postoperative Quality of Recovery Scale at 15 min and 40 min; days 1, 3, 7, 14; and 1 and 3 months after surgery. Chi-square test was used for the primary outcome, and generalised linear mixed model for recovery over time between groups. Of 350 participants randomised, 140 (deep) and 144 (moderate) were analysed for the primary outcome. There was no difference in the Postoperative Quality of Recovery Scale cognitive domain at day 7 (deep 92.9% vs. moderate 91.8%, OR 1.164; 95%CI 0.486–2.788, p = 0.826), or at any other time-point. No significant difference was observed for physiological, emotive, activities of daily living, nociception, or overall recovery. Length of stay in the recovery area (mean (SD) deep 108 (58) vs. moderate 109 (57) min, p = 0.78) and hospital (1.8 (1.9) vs. 2.6 (3.5) days, p = 0.019) was not different. Intra-abdominal pressure and surgical operating conditions were not different between groups. Deep neuromuscular block did not improve quality of recovery compared with moderate neuromuscular block in operative laparoscopic surgery over a 1-h duration.  相似文献   
22.
BackgroundIatrogenic root perforations are an unfortunate accident that can occur during dental treatment and can lead to peri-radicular damage, poor treatment outcome and extraction of the tooth. The aim of this review was to analyse the occurrence and risk factors for root perforation.MethodsA systematic search of the literature was conducted in CINAHL, Cochrane, EMBASE, Medline and SCOPUS in May 2019. Additional literature was identified through a hand search. Clinical studies enrolling adults with permanent dentition were included. Single case studies and case reports were excluded. Duplicate articles were removed, titles and abstracts were screened and studies were selected according to the inclusion criteria. Data were collected and reported in accordance with PRISMA guidelines. Risk of bias was assessed using the Joanna Briggs Institute Critical Appraisal Tools.ResultsA total of 916 articles were screened, from which 47 full-text articles were analysed and 22 articles were finally included in the study. The data were analysed qualitatively because meta-analysis could not be conducted owing to lack of heterogeneity among the studies. Most of the articles were retrospective cross-sectional studies on root canal treatments performed by undergraduate students. The occurrence of perforation ranged from 0.6% to 17.6%. Risk factors for perforation included experience of the practitioner, tooth type, and tooth morphology. The risk of bias in most of the studies included was assessed as low.ConclusionsThis systematic review suggests a need for additional studies on the risk factors associated with iatrogenic root perforation as the current literature is insufficient. Educational efforts in dental schools should address the issue of perforations and provide more clinical experience prior to graduation in order to improve the clinical skills of graduates.  相似文献   
23.
24.
25.
26.
The authors report a 57-year-old man who survived 18 days after swallowing an 8-oz. can of Sterno in a suicide attempt. Two days after ingestion, he developed confusion and acute renal failure requiring hemodialysis, followed on day 8 by a delayed but rapidly evolving ascending paralysis. Pathologic examination showed severe demyelination, with lesser axonal damage, of virtually all cranial and peripheral nerves sampled and sparing of central myelin. The diethylene glycol in the Sterno was considered responsible for this intoxication.  相似文献   
27.
Five dairy cows were fed 0–50 ppm diuron herbicide [3-(3,4-dichlorophenyl)-1,1-dimethylurea] for 33 days and samples of milk, blood, urine, and feces were collected at regular intervals during the experiment. Approximately 50% of the diuron was recovered in urine, 10% in feces, and 5% in blood. No herbicide was detected in milk. In general, there was a positive correlation in the concentration of diuron products between urine and blood and a negative correlation between urine and feces. However, the percentage excretion of diuron residues in urine, feces, or blood was consistent in all treatments. The remaining > 35% of diuron, which was not detected, could have been absorbed in the body or degraded into undetectable metabolites. Two diuron metabolites, 3-(3,4-dichlorophenyl)-1-methylurea (DCMU) and 3-(3,4-dichlorophenyl)urea (DCU), were identified and determined only in urine from animals treated with 25 and 50 ppm due to experimental difficulties. Moreover, DCMU and DCU accounted for 8 and 25%, respectively, of diuron intake.  相似文献   
28.
PURPOSE: We assessed the potential of magnetic resonance urography (MRU) in the evaluation of hydronephrosis not explained by standard investigation in patients at high risk for upper tract urothelial cancer. MATERIALS AND METHODS: A total of 23 consecutive patients in a specialist urological unit with unexplained hydronephrosis prospectively underwent MRU which comprised overview heavily T2-weighted MR urographic images followed by focused high resolution turbo spin echo T2-weighted sequences obtained in an axial and coronal oblique plane through the level of urinary obstruction. All were at high risk for urothelial cancer and had either contraindications to or problems with standard investigations including poor contrast excretion due to obstruction or renal failure, failed ureteral cannulation or contrast allergy. Clinical events and imaging followup, subsequent endoscopic/surgical findings and histopathology validated MR findings. RESULTS: In 23 patients with a high clinical suspicion of upper tract transitional cell tumors (TCC), 8 ureteral and 5 renal pelvic TCCs (2 bilateral) were diagnosed by MR, and confirmed histologically. In a further 5 patients benign causes for the hydronephrosis were found. No intrinsic or extrinsic pathology was demonstrable in 5 patients whose imaging findings were stable during 1 year of followup. CONCLUSIONS: MRU is a valuable noninvasive investigation for evaluating hydronephrosis in this group of patients with suspected urothelial cancer in which routine investigation had failed to provide clinically important information. Focused high resolution T2-weighted images were reliable in the diagnosis of ureteral and renal pelvic TCCs, and were valuable in excluding these and other mass lesions as the cause of hydronephrosis.  相似文献   
29.
Caliceal fistula is a rare complication after renal transplant and may lead to graft failure. We present a case of complex caliceal-cutaneous and caliceal-peritoneal fistula in a renal transplant patient who was successfully managed conservatively.  相似文献   
30.
OBJECTIVES: To study the morbidity of radical cystectomy and radical radiotherapy in the treatment of patients with invasive carcinoma of the bladder and to report the long-term survival following these treatments. PATIENT AND METHODS: 398 patients with invasive carcinoma of the bladder treated between 1993 and 1996 in the Yorkshire region were studied. Of 398 patients studied, 302 patients received radical radiotherapy and 96 underwent radical cystectomy. A retrospective review of patients' case notes was performed to construct a highly detailed database. Crude estimates of survival differences were derived using Kaplan-Meier methods. Log-rank tests (or, where appropriate, Wilcoxon tests) were used to test for the equality of these survivor functions. These functions were produced as all-cause survival. The proportional hazards regression modelling was used to assess the impact of definitive treatment on survival. A backwards-stepwise approach was used to derive a final predictive model of survival, with likelihood ratio tests to assess the statistical significance of variables to be included in the model. RESULTS: The patients undergoing radiotherapy were significantly older (mean age: 71 years versus 66 years), but no difference was identified in the distribution of American Society of Anaesthesiologists (ASA) grades in the two treatment groups. The stage distribution of cases in the treatment groups was not significantly different. Significant treatment delays were observed in both treatment groups. The median time from being seen in the clinic to transurethral resection of bladder tumour (TURBT) and subsequent radical treatment (cystectomy or radiotherapy) was 4.3 and 9 weeks, respectively. Age was the most significant independent factor accounting for treatment delays (p < 0.001). The 30-day and 3-month treatment-associated mortality for radical cystectomy and radiotherapy was 3.1% and 8.3% and 0.3% and 1.65%. Of the patients who received radiotherapy, 57 (18.8%) were subsequently subjected to a salvage cystectomy. For these 57 patients, 30-day and 3-month mortality after the salvage cystectomy were 8.8% and 15.7%. Gastrointestinal complications were the major source of early morbidity after primary and salvage cystectomy. Bowel leakage occurred in 3% following radical and 8.7% after salvage cystectomy. Bowel complications (leakage and obstruction) were the major cause of death following salvage cystectomy. No specific cause was predominant in those undergoing radical cystectomy with intestinal anastomotic leakage and urinary leakage accounting for one death each. Exacerbation of co-morbid conditions accounted for the remaining causes of mortality. Urinary leakage occurred in 4% following both forms of cystectomy. Recurrent pyelonephritis and intestinal obstruction were responsible for the majority of complications in the follow-up period. Bladder and gastrointestinal complications accounted for the majority of complications following radical radiotherapy. Some degree of irritative bladder and rectal were noted commonly. Severe bladder problems, which rendered the bladder non-functional or required surgical correction, occurred in 6.3% of patients. 2.3% of patients underwent surgery for bowel obstruction related to radiotherapy induced bowel strictures. Following radiotherapy, 43.6% of patients had a recurrence in the bladder at varying intervals post-treatment. Of these, 40% had > or =T2 disease. The 5-year survival following radiotherapy (with or without salvage cystectomy) was 37.4% while 36.5% of patients were alive 5 years after radical cystectomy. There was no statistically significant difference in the overall 5-year survival figures between the two primary treatments. Tumour stage, ASA grade and sex were the only independent predictors of 5-year survival on multivariate analysis. CONCLUSIONS: This retrospective regional study shows that there is no significant difference in the 5-year survival of patients with invasive bladder cancer treated with either radical radiotherapy or radical cystectomy. All forms of radical treatment for bladder cancer are associated with a significant treatment-associated morbidity and mortality. Gastrointestinal complications were responsible for the majority of complications. The treatment-associated mortality at 3 months was two- or three-fold higher than the 30-day mortality; emphasising its importance as an indicator of the true risks of cystectomy. The clinical T stage, the sex and the ASA grade of the patient were the only independent predictors of survival. The data in this series suggests that radical radiotherapy and radical cystectomy should be both considered as valid primary treatment options for the management of invasive bladder cancer.  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