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   244篇
  免费   18篇
  国内免费   48篇
儿科学   18篇
妇产科学   1篇
基础医学   39篇
口腔科学   3篇
临床医学   45篇
内科学   35篇
皮肤病学   2篇
神经病学   20篇
特种医学   44篇
外科学   11篇
综合类   21篇
预防医学   31篇
眼科学   2篇
药学   36篇
中国医学   1篇
肿瘤学   1篇
  2022年   4篇
  2020年   3篇
  2019年   3篇
  2018年   6篇
  2015年   7篇
  2014年   6篇
  2013年   14篇
  2012年   8篇
  2011年   7篇
  2010年   7篇
  2009年   7篇
  2008年   7篇
  2007年   35篇
  2006年   6篇
  2005年   8篇
  2004年   3篇
  2003年   6篇
  2002年   4篇
  2001年   8篇
  2000年   7篇
  1999年   8篇
  1998年   11篇
  1997年   12篇
  1996年   17篇
  1995年   9篇
  1994年   7篇
  1993年   15篇
  1992年   7篇
  1991年   3篇
  1990年   7篇
  1989年   4篇
  1988年   6篇
  1987年   4篇
  1984年   2篇
  1982年   6篇
  1981年   4篇
  1980年   2篇
  1978年   2篇
  1977年   4篇
  1976年   3篇
  1975年   1篇
  1973年   1篇
  1970年   2篇
  1969年   2篇
  1968年   3篇
  1966年   3篇
  1965年   2篇
  1962年   1篇
  1960年   1篇
  1955年   1篇
排序方式: 共有310条查询结果,搜索用时 31 毫秒
1.
Over the past decade, the unfortunate reality is that the income gap has widened between Canadian families. Educational outcomes are one of the key areas influenced by family incomes. Children from low-income families often start school already behind their peers who come from more affluent families, as shown in measures of school readiness. The incidence, depth, duration and timing of poverty all influence a child’s educational attainment, along with community characteristics and social networks. However, both Canadian and international interventions have shown that the effects of poverty can be reduced using sustainable interventions. Paediatricians and family doctors have many opportunities to influence readiness for school and educational success in primary care settings.  相似文献   
2.
3.
The effectiveness of a sequential regimen consisting of mifepristone, 10 mg/day for 15 days, followed by nomegestrol acetate (NOMA), 5 mg/day for the next 13 days, for inhibiting ovulation and maintaining regular bleeding cycles was assessed in 10 surgically sterilized volunteers who were followed for one pretreatment and three treated cycles. Hormonal determinations in blood and urine, ovarian ultrasonography, bleeding records in all cycles and an endometrial biopsy taken on day 22-25 of the third treatment cycle were used to monitor the effects of treatment. During treatment, 24 monophasic (no sustained progesterone rise above 12 nmol/l) and six biphasic cycles were recorded. Nine follicular ruptures were detected echographically in these 30 treated cycles, five of which occurred in monophasic cycles. All follicular ruptures occurred on days 1-7 of NOMA treatment. Echographic and endocrine features of ovulatory cycles were both present in only four treated cycles (13.3%). Development of a secretory endometrium was achieved in all cases, but it was always irregular. Regular withdrawal bleeding occurred in all subjects and no adverse reactions were recorded. The ovarian and endometrial effects of this regimen justify testing its contraceptive effectiveness in phase 2 clinical trials.   相似文献   
4.
5.
Zusammenfassung Bei reifen und unreifen Neugeborenen wurde am Beispiel des Sulfasomidins die Beeinflussung der Elimination von Sulfonamiden durch Complamin untersucht.Nach dreitägiger Complamingabe verringerte sich die Eliminationshalbwertszeit um 27,5% (Mittelwert von 23 Kindern). Bei einer Kontrollgruppe von 13 Kindern zeigte sich dagegen keine Veränderung.Complamin führt also bei Neugeborenen zu einer Aktivierung der Sulfonamidelimination, die in dieser Altersgruppe normalerweise verlangsamt ist.
Summary In mature and premature new borns the influence of Complamin on the elimination of sulfonamides was investigated in the example of Sulfasomidin.After 3 days application of Complamin the elimination half time was 27,5% shorter than initially (average of 23 children). A controll group (13 children) showed no alteration. Complamin in new borns induced an activation of sulfonamid elimination, which is normally retarded in this age.
  相似文献   
6.
Summary This study investigated the effect of tilt and observer reliability on radiographic measurements of the position of a prosthetic acetabular cup in seven dry bone pelves using the teardrop as a landmark. Coronal or sagittal tilt of more than five degrees was easily recognisable and there was effectively no observer variation in the measurements up to this limit. In addition, 90 out of 100 randomly selected antero-posterior pelvic radiographs from an outpatient department were not significantly rotated and 93 demonstrated a clearly defined teardrop. Measurements about the teardrop on routine radiographs are therefore sufficiently accurate to allow assessment of prosthetic position.
La valeur du sourcil cotyloidien comme repère d'analyse radiologique
Résumé Cette étude, conduite sur 7 bassins secs, apprécie l'effet de l'inclinaison du bassin sur la qualité de l'analyse radiographique de la position d'une cupule prothétique de hanche en utilisant le sourcil cotyloïdien comme repère. Une inclinaison du bassin dans les plans coronal et sagittal est aisément détectable et il n'existe pas de variation d'analyse entre les différents observateurs en dessous de 5° d'inclinaison. De plus, sur 100 radiographies antéro-postérieures de bassin choisies au hasard dans les dossiers de consultation, 90 avaient été réalisées sans incidence particulièrement adaptée et l'on pouvait repérer facilement le sourcil sur 93% d'entre elles. Les mesures faites sur des radios de routine sont donc suffisamment précises pour permettre l'évaluation de la position d'une prothèse à partir du sourcil cotyloïdien.
  相似文献   
7.
8.
OBJECTIVE: To determine rates of breast cancer screening for older women cared for in a primary care practice and to identify associations between patient and physician characteristics and breast cancer screening. STUDY DESIGN: A retrospective cohort study of older women. SETTING: An urban hospital-based academic general medicine practice. This practice uses a computerized medical record and office procedures that facilitate tracking and ordering of mammograms. PARTICIPANTS: A random sample of 130 women aged 65 to 80 who receive primary care at a hospital-based general medicine practice. MEASUREMENTS: Data were collected from the hospital's computerized medical record. We recorded all clinical breast exams and mammograms performed or recommended during the 2-year study period. RESULTS: The median age of the 130 women studied was 71, and 21% of the women were black. Most patients had no serious comorbid illness (69%) and were independent in their activities of daily living (92%). During the 2-year study period, mammography was recommended for 95% of women and completed for 84%, and clinical breast exam was performed on 75%. Patients of male physicians had higher rates of mammography than patients of female physicians (89% vs. 75%, P = .045). Patients of faculty physicians had higher rates of clinical breast exam than patients of house officers or fellows (83% vs. 56%, P = .001). CONCLUSIONS: We report a very high rate of mammography for women cared for at a hospital-based primary care practice. The systems in place to facilitate ordering and tracking of mammograms probably contributed to the unusually high rate of mammography observed.  相似文献   
9.

Objectives

The incremental costs of expanding antiretroviral (ARV) drug treatment to all HIV‐infected patients are substantial, so cost‐saving initiatives are important. Our objectives were to determine the acceptability and financial impact of de‐simplifying (i.e. switching) more expensive single‐tablet formulations (STFs) to less expensive generic‐based multi‐tablet components. We determined physician and patient perceptions and acceptance of STF de‐simplification within the context of a publicly funded ARV budget.

Methods

Programme costs were calculated for patients on ARVs followed at the Southern Alberta Clinic, Canada during 2016 (Cdn$). We focused on patients receiving Triumeq® and determined the savings if patients de‐simplified to eligible generic co‐formulations. We surveyed all prescribing physicians and a convenience sample of patients taking Triumeq® to see if, for budgetary purposes, they felt that de‐simplification would be acceptable.

Results

Of 1780 patients receiving ARVs, 62% (= 1038) were on STF; 58% (= 607) of patients on STF were on Triumeq®. The total annual cost of ARVs was $26 222 760. The cost for Triumeq® was $8 292 600. If every patient on Triumeq® switched to generic abacavir/lamivudine and Tivicay® (dolutegravir), total costs would decrease by $4 325 040. All physicians (= 13) felt that de‐simplifying could be safely achieved. Forty‐eight per cent of 221 patients surveyed were agreeable to de‐simplifying for altruistic reasons, 27% said no, and 25% said maybe.

Conclusions

De‐simplifying Triumeq® generates large cost savings. Additional savings could be achieved by de‐simplifying other STFs. Both physicians and patients agreed that selective de‐simplification was acceptable; however, it may not be acceptable to every patient. Monitoring the medical and cost impacts of de‐simplification strategies seems warranted.
  相似文献   
10.
目的:神经断端保留小间隙的静脉桥接模拟神经外膜形成神经再生室,为周围神经再生创造了良好的生理环境,从而保证神经束的良好对合。实验采用部分脱乙酰甲壳质作为套管材料,用小间隙桥接方法修复坐骨神经损伤,观察套管内的神经再生情况,并与传统外膜缝合法进行比较。方法:实验于2001-01/2002-10在北京大学人民医院创伤骨科实验室完成。①主要材料:实验所用中空圆柱形套管为北京大学人民医院与中国纺织科学院共同发明的一种部分脱乙酰甲壳质生物套管(专利号:01136314.2)。实验中所用套管尺寸为:管长4 mm,壁厚0.1 mm,内径1.5 mm。②实验动物:健康成年雄性SD大鼠20只,随机分成2大组,每组10只,每一大组全部10只动物的左腿坐骨神经为一组,右腿坐骨神经为另一组,每组10根坐骨神经。另取5只同样大鼠双侧坐骨神经未做处理作为正常对照组。③实验方法:外膜原位缝合组:切断坐骨神经,显微镜下神经外膜原位缝合;生物套管小间隙原位桥接组:切断坐骨神经,显微镜下小间隙套管桥接;断端旋转180°外膜缝合组:切断坐骨神经,显微镜下远端旋转180°后,神经外膜缝合;断端旋转180°生物套管小间隙桥接组:切断坐骨神经,显微镜下远端旋转180°后,小间隙套管桥接。④实验评估:术后第7,14,21,28,42天取坐骨神经,进行免疫组织化学染色及观察。结果:再生神经延套管中央走行,7 d时已有部分纤维通过2 mm间隙,14 d时有髓纤维数量明显多于近端。21 d后,套管组与原位外膜组新生有髓神经纤维数相近。再生纤维胞核数量较多,髓鞘纤细。套管结构完整。结论:此种部分脱乙酰甲壳质生物套管内的再生神经连续、整齐,髓鞘完整,其神经再生情况好于传统外膜缝合法。  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