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   159篇
  免费   23篇
  国内免费   15篇
儿科学   11篇
妇产科学   2篇
基础医学   30篇
口腔科学   2篇
临床医学   13篇
内科学   36篇
神经病学   24篇
特种医学   3篇
外科学   1篇
综合类   2篇
预防医学   27篇
药学   42篇
肿瘤学   4篇
  2022年   1篇
  2021年   2篇
  2020年   18篇
  2019年   4篇
  2018年   2篇
  2017年   1篇
  2015年   1篇
  2014年   5篇
  2013年   7篇
  2012年   6篇
  2011年   6篇
  2010年   8篇
  2009年   4篇
  2008年   5篇
  2007年   12篇
  2006年   5篇
  2005年   7篇
  2004年   2篇
  2003年   4篇
  2002年   8篇
  2001年   5篇
  2000年   9篇
  1999年   6篇
  1998年   8篇
  1997年   4篇
  1996年   5篇
  1995年   4篇
  1994年   8篇
  1993年   6篇
  1992年   6篇
  1991年   5篇
  1990年   6篇
  1989年   4篇
  1988年   3篇
  1987年   2篇
  1986年   2篇
  1985年   2篇
  1984年   3篇
  1983年   1篇
排序方式: 共有197条查询结果,搜索用时 13 毫秒
41.
42.
硝基甘油对狗缺血区冠脉循环的作用   总被引:1,自引:0,他引:1  
用实验性犬冠脉狭窄模型,冠脉内恒流灌注硝基甘油0.5μg/kg.min-1,使冠脉血流量(CBF)增加、远端小动脉压(DCP)、冠脉血管总阻力(RT)、小冠脉血管阻力(RS)及冠状静脉低切血粘(ηb)减少;而主动脉压和心率无明显变化。恒流灌注硝基甘油1μg/kg.min-1时,在开始5min内冠脉循环的变化同上,并伴大冠脉血管阻力(RL)减少,10 min后出现CBF减少和RT,RL及ηb增加。结果提示,硝基甘油有缓解和加重心肌缺血的双重作用,其作用可能与剂量张扩张远端小动脉压的程度有关。  相似文献   
43.
This pilot study investigated the relationship between parental criticism and medical treatment outcome across an inpatient hospitalization in 19 adolescents with severe, chronic asthma. Parental criticism toward their asthmatic adolescent was assessed using the Five Minute Speech Sample technique (FMSS) at the beginning of the adolescent's inpatient stay at a national asthma referral center. Those adolescents whose parents were rated as high in criticism on the FMSS were found to have greater improvement in their overall asthma severity, greater reduction in their steroid medication dose, and shorter lengths of stay in the hospital than those whose parents were rated as low in criticism. The adolescents whose parents were rated as high in criticism also showed lower compliance with their prescribed theophylline and oral steroid medication at admission than the low criticism group. These findings do not appear to be due to misdiagnosis secondary to the presence of vocal cord dysfunction or to the allergy status of the children. Clinical implications and possible causal mechanisms underlying these findings are discussed.  相似文献   
44.
隋文  肖明振  洪咏龙 《医学争鸣》1999,20(8):S027-S028
0 引言 牙釉质是由一种特殊的、来源于原始口腔上皮的上皮细胞-成釉细胞分泌的. 牙齿的上皮细胞是以一种特殊的时空方式,分化成有一定功能的成釉细胞,它与来源于外胚间充质的成牙本质细胞的分化有密切的关系[1]. 釉原蛋白是一族基质相关蛋白,由成釉细胞在形成牙釉质时合成和分泌. 釉原蛋白具有非常复杂的生物学功能,迄今为止其确切的功能还不清楚[2],我们对大鼠牙胚发育的不同时期釉原蛋白的表达进行定位,为今后进一步研究釉原蛋白的生物学功能、釉质的生物矿化、细胞的分化奠定基础.  相似文献   
45.
46.
BACKGROUND: Steroid insensitivity increasingly is being recognized in patients with severe, chronic asthma. Virtually no data exist regarding the clinical outcomes of steroid insensitive (SI) asthma despite clear expectations of poorer longitudinal course for this condition. METHODS: We obtained 2-year follow-up data from 34 pediatric patients who had been evaluated for steroid insensitivity at a national asthma referral center. Outcomes evaluated included current oral glucocorticoid (GC) dose; number of GC bursts, emergency room visits, and hospitalizations for asthma in the prior 12 months; Asthma Functional Severity; Pediatric Asthma Quality of Life; and Pediatric Asthma Caregiver's Quality of Life. RESULTS: At follow-up, patients with SI asthma and their caregiving parent both reported poorer quality of life (QOL) compared with those with steroid sensitive (SS) asthma (adolescent: 4.6 +/- 0.4 versus 5.6 +/- 0.3; P < .05; caregiver: 5.1 +/- 0.4 versus 6.2 +/- 0.2; P < .05). Steroid-insensitive patients showed no significant difference in GC dose, number of GC bursts, emergency room visits or hospitalizations, or Asthma Functional Severity compared with SS patients. CONCLUSIONS: Steroid insensitivity was associated with significantly poorer QOL at 2-year follow-up. Steroid insensitive patients did not show poorer clinical outcomes compared with SS patients as assessed by current steroid requirements and health care utilization. Overall, the observed pattern of results suggests that SI asthma may be a worse form of asthma because a more fixed pattern of lung obstruction has developed. Further longitudinal study of the clinical and cellular outcomes of SI asthma is needed to more fully characterize the types and magnitude of risks associated with SI status.  相似文献   
47.
Acceptance of current treatment guidelines by physicians and adherence to the recommended clinical regimens by patients are essential for effective asthma therapy. Treatment plans must be based on up-to-date management guidelines and should comprise a strategy for the evaluation and support of patient adherence. Monitoring of adherence with electronic devices enables physicians to base clinical decisions on reliable and objective data. Assessment of prescribing quality should be used to improve treatment of all patients.  相似文献   
48.
The equivalent sensitivity of non‐contrast computed tomography (NCCT) and intravenous urography (IVU) in the diagnosis of suspected ureteric colic has been established. Approximately 50% of patients with suspected ureteric colic do not have a nephro‐urological cause for pain. Because many such patients require further imaging studies, NCCT may obviate the need for these studies and, in so doing, be more cost effective and involve less overall radiation exposure. The present study compares the total imaging cost and radiation dose of NCCT versus IVU in the diagnosis of acute flank pain. Two hundred and twenty‐four patients (157 men; mean age 45 years; age range 19–79 years) with suspected renal colic were randomized either to NCCT or IVU. The number of additional diagnostic imaging studies, cost (IVU A$136; CTU A$173), radiation exposure and imaging times were compared. Of 119 (53%) patients with renal obstruction, 105 had no nephro‐urological causes of pain. For 21 (20%) of these patients an alternative diagnosis was made at the initial imaging, 10 of which were significant. Of 118 IVU patients, 28 (24%) required 32 additional imaging tests to reach a diagnosis, whereas seven of 106 (6%) NCCT patients required seven additional imaging studies. The average total diagnostic imaging cost for the NCCT group was A$181.94 and A$175.46 for the IVU group (P < 0.43). Mean radiation dose to diagnosis was 5.00 mSv (NCCT) versus 3.50 mSv (IVU) (P < 0.001). Mean imaging time was 30 min (NCCT) versus 75 min (IVU) (P < 0.001). Diagnostic imaging costs were remarkably similar. Although NCCT involves a higher radiation dose than IVU, its advantages of faster diagnosis, the avoidance of additional diagnostic imaging tests and its ability to diagnose other causes makes it the study of choice for acute flank pain at Christchurch Hospital.  相似文献   
49.
五味子醇甲的代谢转化   总被引:7,自引:1,他引:7  
采用动物肝微粒体体外代谢法对五味子醇甲的代谢转化进行了研究。从体外代谢产物中鉴定其主要的三个代谢物为:7,8-顺二羟基五味子酸甲;7,7-顺二羟基-2-去甲基五味子醇甲及7,8-顺二羟基-3-去甲基五味子醇甲。在此基础上,建立了生物体液中五味子醇甲及其代谢物的反相HPLC分析方法,并用此法检测了服药后大鼠的胆汁及尿样,比较了体外代谢与体内代谢的异同。  相似文献   
50.
Abstract Excessive alcohol use in COPD has been associated with increased mortality; however, little is known about alcohol use in AATD-associated COPD. A total of 538 individuals with AATD-associated COPD completed questionnaires at baseline and 330 also completed 2?years of follow-up questionnaires. Demographic and health information was collected, including information about alcohol use, ER visits for COPD, and hospitalizations for COPD. Problem alcohol use was characterized using the CAGE screening questionnaire and recent alcohol consumption. Demographic and clinical characteristics associated with problem drinking were identified using logistic regression. Problem drinking at baseline was examined as a predictor of ER visits and hospital admissions for COPD in the subsequent two years using logistic regression adjusting for demographic variables and baseline health status. 14% of the sample reported a history of problem drinking per the CAGE and 8% reported problem drinking in the past week. Problem drinking was associated with higher education and greater lifetime tobacco exposure. Recent alcohol consumption was a significant predictor of having an ER visit for COPD in the subsequent two years. Compared to individuals who reported problem drinking in the past week, individuals with no consumption (OR = 0.32, 95% CI = 0.10 to 0.97, p = .043) and individuals with low-to-moderate consumption (OR = 0.25, 95% CI = 0.08 to 0.77, p = .016) had significantly lower odds of an ER visit. Neither measure of problem drinking predicted hospital admission. Screening for recent excessive alcohol use in this population may identify individuals at risk for use of costly emergency health services.  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