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   464篇
  免费   21篇
  国内免费   3篇
耳鼻咽喉   18篇
儿科学   14篇
妇产科学   63篇
基础医学   8篇
口腔科学   18篇
临床医学   31篇
内科学   20篇
皮肤病学   7篇
神经病学   9篇
特种医学   11篇
外科学   132篇
综合类   49篇
预防医学   34篇
药学   24篇
中国医学   3篇
肿瘤学   47篇
  2023年   9篇
  2022年   16篇
  2021年   35篇
  2020年   20篇
  2019年   21篇
  2018年   26篇
  2017年   12篇
  2016年   12篇
  2015年   14篇
  2014年   29篇
  2013年   33篇
  2012年   27篇
  2011年   39篇
  2010年   22篇
  2009年   25篇
  2008年   22篇
  2007年   18篇
  2006年   16篇
  2005年   18篇
  2004年   12篇
  2003年   9篇
  2002年   3篇
  2001年   5篇
  2000年   4篇
  1999年   4篇
  1998年   1篇
  1997年   3篇
  1996年   4篇
  1994年   5篇
  1993年   1篇
  1992年   1篇
  1991年   1篇
  1989年   4篇
  1988年   1篇
  1987年   1篇
  1985年   3篇
  1984年   4篇
  1983年   1篇
  1982年   2篇
  1980年   1篇
  1979年   3篇
  1978年   1篇
排序方式: 共有488条查询结果,搜索用时 15 毫秒
1.
BackgroundCarbetocin has been found to be superior to oxytocin in terms of need for additional uterotonics and prevention of postpartum haemorrhage at caesarean delivery. However, this is based on combined data from labouring and non-labouring parturients and it remains unclear how effective carbetocin is in the purely elective setting. The aim of this review was to compare carbetocin to oxytocin in elective caesarean delivery.MethodsMedline, Embase, CINAHL, Web of Science, and the Cochrane databases were searched for randomised controlled trials in any language. The primary outcome was need for additional uterotonics. Secondary outcomes were mean blood loss, need for blood transfusion and incidence of postpartum haemorrhage >1000 mL.ResultsNine studies with a total of 1962 patients were included. Trial sequential analysis confirmed that the information size (n=1692) had surpassed that required (n=1166) in order to demonstrate a statistically significant reduction in the use of additional uterotonics. Need for additional uterotonics was reduced by 53% with carbetocin compared to oxytocin (OR 0.47, 95% CI 0.34 to 0.64; P <0.001, I2=63.5). The number needed-to-treat was 11. The risk of bias, data heterogeneity and inconsistency in reporting bleeding outcomes made it difficult to reach definite conclusions about prevention of PPH.ConclusionsCarbetocin is associated with a reduced need for additional uterotonics when compared with oxytocin at elective caesarean delivery. Standardisation of bleeding-related outcomes in studies is necessary to facilitate synthesis of data in future analyses.  相似文献   
2.
The aim of this study was to assess the impact of delivery on the pelvic floor and whether cesarean section (C/S) can prevent pelvic floor injury. Five hundred thirty nine women were divided into three groups according to the delivery method adopted: elective C/S, emergent C/S, and vaginal delivery. A urinary incontinence questionnaire survey was conducted around 1 year postpartum. Emergent C/S may be a major risk factor for postpartum urinary incontinence and interfere with the benefit of elective C/S for preventing pelvic floor injury. Hence, not all C/S deliveries can reduce the likelihood of postpartum urinary incontinence. The key lies in whether the C/S is performed before labor.  相似文献   
3.
如何上好医学生药品质量选修课   总被引:1,自引:1,他引:0  
医学生在以后的工作中会经常接触到药品,而药品质量的好坏直接关系到患者的生命安全,因此在医学生中开设药品质量选修课非常必要。本文从教学方法、教学手段、教学内容的衔接等方面提出了一些观点和具体方法。  相似文献   
4.
Background: There has been a debate about the cost-effectiveness of laparoscopic cholecystectomy (LC), as well as a concern regarding its possible overutilization and changes in the indication for surgery. Methods: A retrospective analysis of all cholecystectomies performed at UCDMC from 1988 to 1994 was done. The annual rate of cholecystectomy increased by 50% in 1990 when LC was introduced but has since stabilized at a rate 11% higher than the rate before LC. The disease status and severity did not change. Results: The incidence of nonelective surgery remained stable at 31.2% to 37.5%. Elective cholecystectomy had lower mortality (0.16% vs 1.8%, P=0.029), morbidity (2.6% vs 11.2%, P=0.0001), and conversion rate (2.6% vs 16%, P=0.0001) and a shorter length of stay (2.1 days vs 5.4 days), compared with nonelective procedure. Conclusions: The indication for surgery in cholelithiasis has not changed since the introduction of LC. In patients with symptomatic gallstones, early elective surgery is recommended and may be more cost-effective.Presented at the annual meeting of the Society of American Gastrointestinal Endoscopic Surgeons (SAGES), Orlando, FL, March 12–14, 1995  相似文献   
5.
BackgroundInduction of labor continues to become more common. We analyzed induction of labor and timing of obstetric and anesthesia work to create a model to predict the induction-anesthesia interval and the induction-delivery interval in order to co-ordinate workload to occur when staff are most available.MethodsPatients who underwent induction of labor at a single medical center were identified and multivariable linear regression was used to model anesthesia and delivery times. Data were collected on date of birth, race/ethnicity, body mass index, gestational age, gravidity, parity, indication for labor induction, number of prior deliveries, time of induction, induction agent, cervical dilation, effacement, and fetal station on admission, date and time of anesthesia administration, date and time of delivery, and delivery type.ResultsA total of 1746 women met inclusion criteria. Associations which significantly influenced time from induction of labor to anesthesia and delivery included maternal age (anesthesia P <0.001, delivery P =0.002), body mass index (both P <0.001), prior vaginal delivery (both P <0.001), gestational age (anesthesia P <0.001, delivery P <0.018), simplified Bishop score (both P <0.001), and first induction agent (both P <0.001). Induction of labor of nulliparous women at 02:00 h and parous women at 04:00 or 05:00 h had the highest estimated probability of the mother having her first anesthesia encounter and delivering during optimally staffed hours when our institution’s specialty personnel are most available.ConclusionsTime to obstetric and anesthesia tasks can be estimated to optimize induction of labor start times, and shift anesthesia and delivery workload to hours when staff are most available.  相似文献   
6.
7.
Elective vs. conservative management of ovarian tumors in pregnancy.   总被引:6,自引:0,他引:6  
OBJECTIVES: To determine optimal management of the ovarian tumors in pregnancy. METHODS: This study included 89 cases of the ovarian tumor in pregnancy that required surgery at Holy Family hospital of the Catholic University from January, 1990 to December, 2001. Among 89 cases, 36 and 53 were emergency and elective surgery, respectively. Student's t-test and the chi(2)-test were used for statistical analysis and a P-value of <0.05 was considered statistically significant. RESULTS: The most common size of torsion of ovarian tumors during pregnancy was 6-10 cm and the incidence was the most frequent during the first trimester of pregnancy. The incidence of preterm delivery (<37 weeks) was higher in emergency surgery, but there was no difference in the gestational age at delivery, also no difference in the birth weight or the method of delivery. CONCLUSIONS: Although surgery for ovarian tumors in pregnancy is delayed until the onset of symptoms, adverse pregnancy outcome is not worsened when compared with that after elective surgery. We propose that conservative management would be used in optimal management of pregnant women with ovarian tumors.  相似文献   
8.
目的探讨人工髋关节置换术后静脉血栓栓塞的预防。方法2004年2月~2005年12月行人工全髋关节置换术43例、人工股骨头置换术26例。对所有患者均进行了由纤溶酶静脉滴注,踝关节主、被动“环转”运动及持续被动活动机(CPM)治疗等组成的静脉血栓栓塞综合防治。结果69例患者在观察期内均未出现下肢深静脉血栓栓塞及肺栓塞表现,二维彩色多普勒超声检查示静脉血流通畅。结论综合防治对于预防人工髋关节置换术围手术期静脉血栓栓塞的发生具有积极的临床意义。  相似文献   
9.
Elective caesarean section for women in labour with an immature baby might reduce the chances of fetal or neonatal death, but might also increase the risk of maternal morbidity. A review (updated in February 2004) of randomised trials comparing a policy of elective caesarean section versus expectant management with recourse to caesarean section produced six studies involving only 122 women. Differences in fetal outcome did not reach significance, but mothers undergoing elective caesarean section were more likely to have serious morbidity. Scientifically, the evidence remains inadequate. Clinically, the recommendation is that prematurity is not, in itself, an indication for caesarean section. In a survey from Israel, published in December 2004, of 2955 very low birthweight infants born at 24–34 weeks of gestation, the overall caesarean section rate was 51.7%, and the mortality rate among babies prior to discharge was lower after caesarean section (13.2 versus 21.8%). After adjustment using multiple logistic regression, caesarean section had no effect on survival except in a subgroup with amnionitis, and it was again concluded that caesarean section cannot be routinely recommended unless there are other indications. A decision model developed in the USA has compared costs and health outcomes of two options for managing labour at 24 weeks of gestation. The probabilities of both intact survival (16.8 versus 12.9%) and survival with major morbidity (39.2 versus 19.4%) are higher with willingness to perform caesarean section, but less aggressive management is the more cost-effective strategy. Large studies are few and recruitment to such studies is perceived as a major problem. For clinicians, the decision will be influenced by local circumstances.  相似文献   
10.
The incidence of metastases following neck dissection in the apparent lymph node negative neck in oral cancer is between 7% and 33%; early resection of cervical metastases may well increase survival. Modern imaging techniques can reduce the yield of previously undiagnosed metastatic nodes in elective neck dissection (END). An audit of 112 consecutive cases was conducted to determine the proportion of undiagnosed nodal metastases, after END. There were neck metastases in 10 cases (9%), which were mainly (but not all) micrometastic. The 20% likelihood of nodal metastases was only apparent in primary tumours greater than 6 mm thick. The length of inpatient stay was increased from 3.7 to 16.5 days with free vascularised transfer. There were complications including cranial nerve damage. There were two peri-operative deaths. No ipsilateral neck failures occurred, median follow up was 937 days. To reduce unnecessary END, resection can be undertaken as a prior procedure, subsequently only carrying out END on tumours greater than 6 mm, or with unfavourable tumour characteristics.  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