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   1328篇
  免费   110篇
耳鼻咽喉   11篇
儿科学   111篇
妇产科学   21篇
基础医学   134篇
口腔科学   26篇
临床医学   99篇
内科学   378篇
皮肤病学   22篇
神经病学   93篇
特种医学   24篇
外科学   157篇
综合类   44篇
预防医学   60篇
眼科学   44篇
药学   147篇
中国医学   14篇
肿瘤学   53篇
  2023年   8篇
  2022年   21篇
  2021年   33篇
  2020年   33篇
  2019年   42篇
  2018年   40篇
  2017年   31篇
  2016年   37篇
  2015年   38篇
  2014年   48篇
  2013年   93篇
  2012年   139篇
  2011年   105篇
  2010年   60篇
  2009年   44篇
  2008年   70篇
  2007年   78篇
  2006年   68篇
  2005年   66篇
  2004年   54篇
  2003年   43篇
  2002年   46篇
  2001年   35篇
  2000年   36篇
  1999年   24篇
  1998年   8篇
  1997年   9篇
  1996年   6篇
  1995年   6篇
  1993年   5篇
  1992年   5篇
  1991年   10篇
  1990年   7篇
  1988年   5篇
  1986年   4篇
  1984年   11篇
  1983年   4篇
  1980年   4篇
  1978年   8篇
  1976年   6篇
  1975年   4篇
  1974年   4篇
  1973年   3篇
  1972年   2篇
  1971年   2篇
  1970年   4篇
  1969年   2篇
  1967年   3篇
  1965年   4篇
  1948年   3篇
排序方式: 共有1438条查询结果,搜索用时 15 毫秒
1.
2.
Wistar strain adult male and female rats were given 25, 50 and 75% less food than an ad libitum-fed group of rats for 45 d and the effects of food restriction on hepatic drug metabolizing enzymes, microsomal electron transport components, NADPH-dependent lipid peroxidation and glutathione-S-transferase activities were studied. Compared to ad libitum-fed controls, the cytochrome P-450 levels were higher in food restricted male rats, while they were lower in food restricted females. The activities of NADPH cytochrome c reductase were lower in food restricted females than in ad libitum-fed controls. The activities of drug metabolizing enzymes, aminopyrine N-demethylase and acetanilide hydroxylase were higher in food restricted males, whereas in food restricted females these activities were lower than in respective groups fed ad libitum. Microsomal, NADPH-dependent lipid peroxidation was higher in 25 and 50% food restricted females while in 50 and 75% food restricted males it was lower than in ad libitum controls of the same sex. The cytosolic glutathione-S-transferase activities were lower in food restricted rats of both the sexes than in the same sexed controls. Another group of male and female rats were given 75% less food than the ad libitum-fed rats and refed for 3 d prior to killing. Here also, the effects of restriction were different between sexes. It is concluded that hepatic microsomal mixed-function oxidase system (MFOS) is altered due to feed restriction and food restriction followed by refeeding, in a sex-related manner.  相似文献   
3.
4.
5.
Some variation in the phenotype of patients with dup(18q) is recognized. Our patient has the phenotype described for dup(18qter).  相似文献   
6.
7.
The aim of the present paper was to identify, appraise, and synthesize the available evidence on two‐stage revision hip arthroplasty with or without the use of an interim spacer for managing late prosthetic infection. The review methodology was designed by referencing the Preferred Reporting Items for Systematic Reviews and Meta‐analyses (PRISMA) checklist and flow diagram, and a Population, Intervention, Comparator, Outcomes and Study (PICOS) design framework was used to search for studies to incorporate within the review. Two independent investigators were involved in searching for relevant articles that fulfilled the inclusion criteria for the study. Critical appraisal of the selected articles was carried out using the relevant Critical Appraisal Skills Programme checklists. From an initial pool of 125 articles, four studies satisfied the inclusion criteria and quality assessment and were included for final review. Two patient groups were identified from within the selected studies: spacer and non‐spacer. Both groups were assessed in terms of functional outcome, infection cure rates, and technical difficulties encountered during treatment. Better functional outcome was reported in the spacer group, both in the interim period between the two stages and after completion of treatment. The use of spacers reduced operative difficulty during the second stage and accelerated patient discharge. Reinfection and infection persistence rates were higher in the non‐spacer group. Within the spacer group, articulated spacers performed better in all parameters. The results of this review reinforce the available evidence supporting the use of interim hip spacers in revision hip arthroplasty for managing prosthetic infection and also indicate that articulated hip spacers could be an attractive option going forward.  相似文献   
8.
In this prospective study, birth weight of 304 babies born at Kamla Nehru Hospital Pune during study period was recorded. From these 304 babies, babies with birth weight above 2000 grams were selected (260 babies) to prepare growth velocity curves. Daily weight of these 260 babies was recorded for 30 days. The mean birth weight of study population was 2742.5 grams. Among the daily weight recorded babies, all the babies lost weight ranging from 92 to 218 grams (mean 121 grams) after birth. The weight loss continued upto 5 days. Days required to gain weight equal to birth weight ranged from 5 to 13 days. Total weight gain observed in 30 days was 734.7 grams. Predictive value of these curves was tested in 49 infants. Deviation upto 50 grams of predicted birth weight from actual birth weight was observed in 90% of babies on day-2, 79% on day-4, 65% on day-8 and 39% on day-30.  相似文献   
9.
Studies of preemptive analgesia in humans have shown conflicting results. The study design, patient population and the duration of assessment of postoperative pain are important in the evaluation of preemptive analgesia. We carried out a prospective, randomized, double-blind controlled study in 80 patients of physical status ASA 1-3 undergoing upper abdominal and thoracic surgery. Patients received two epidural injections, one 20 minutes before induction and the other at the end of surgery. Study solution was either morphine (50 micrograms/kg), with or without 0.1% bupivacaine in 10 ml of normal saline, or normal saline alone. The study groups (Pre M, Pre MB) were given either morphine or morphine-bupivacaine before induction and saline at the end of surgery. The control groups (Post M, Post MB) were given saline before induction and morphine or morphine-bupivacaine at the end of surgery. Postoperative pain was assessed with a Visual Analogue Scale (VAS) during coughing and deep breathing at six-hourly intervals for five days. Epidural morphine was given if the VAS exceeded 4. Pre MB compared to Post MB had a significantly increased interval between the analgesic top-ups (P < 0.01) and decreased total postoperative morphine requirements (P < 0.0001) and number of top-ups (P < 0.001). Pre M and Post M were comparable. Pre MB compared to Pre M had significantly decreased total postoperative morphine requirements (P < 0.0001) and number of top-ups (P < 0.0001). Epidural morphine plus bupivacaine is effective as a preemptive analgesic. Morphine plus bupivacaine has better efficacy than morphine given alone before the induction of anaesthesia.  相似文献   
10.
Not all trauma victims evaluated by the trauma service require a full complement of laboratory tests upon admission. This study set out to determine the cost savings and safety of limited laboratory testing of trauma victims. Before 1998, our admission trauma protocol included 11 laboratory tests for all trauma victims. In 1998, we created two categories: Trauma Blue--severe injury likely (Glasgow Coma Score <13; systolic blood pressure <100 mm Hg at any time; significant head, chest, abdominal, or proximal long bone injury; or clinical suspicion of need for operative or intensive care unit management) and Trauma Yellow--severe injury unlikely. The triage decision was made by the team leader or attending physician. Trauma Blue laboratory tests included an arterial blood gas, blood alcohol, type and screen or crossmatch, and urine dipstick. All patients who did not meet Trauma Blue criteria were entered in the Trauma Yellow group. There were only two tests for the Trauma Yellow group, a venous blood gas and blood alcohol. All arterial and venous blood gases measured pH, pO2, pCO2, HCO3, base deficit, hemoglobin, sodium, potassium, and ionized calcium. Other laboratory tests were done if requested by the trauma team leader or attending physician. All trauma admissions for a 3-month period were entered into this prospective study. The admitting trauma surgeon was surveyed after each admission to evaluate any problems in patient care. The test group was compared with a historical control of 100 consecutive patients under the original laboratory trauma protocol. One hundred and forty-eight (148) patients were entered into the study. Average laboratory cost per patient was $29.82 less with the study protocol. No patient care problem was identified. A cost savings of $29.82 per patient or $20,000.00 a year was realized for our institution, with no change in the quality of patient care. Trauma protocols designed to reflect a patient's potential for serious injury can result in a significant cost savings while preserving patient safety.  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