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   879篇
  免费   45篇
  国内免费   22篇
儿科学   38篇
妇产科学   2篇
基础医学   85篇
口腔科学   9篇
临床医学   107篇
内科学   194篇
皮肤病学   5篇
神经病学   29篇
特种医学   205篇
外科学   71篇
综合类   8篇
预防医学   71篇
眼科学   16篇
药学   59篇
肿瘤学   47篇
  2021年   8篇
  2019年   5篇
  2018年   7篇
  2017年   7篇
  2015年   14篇
  2014年   8篇
  2013年   22篇
  2012年   28篇
  2011年   22篇
  2010年   25篇
  2009年   19篇
  2008年   29篇
  2007年   37篇
  2006年   28篇
  2005年   25篇
  2004年   18篇
  2003年   17篇
  2002年   17篇
  2001年   17篇
  2000年   11篇
  1999年   17篇
  1998年   38篇
  1997年   48篇
  1996年   26篇
  1995年   31篇
  1994年   22篇
  1993年   14篇
  1992年   12篇
  1991年   14篇
  1990年   15篇
  1989年   33篇
  1988年   35篇
  1987年   20篇
  1986年   30篇
  1985年   30篇
  1984年   15篇
  1983年   13篇
  1982年   22篇
  1981年   11篇
  1980年   22篇
  1979年   13篇
  1978年   12篇
  1977年   11篇
  1976年   16篇
  1975年   8篇
  1974年   4篇
  1972年   8篇
  1970年   7篇
  1969年   4篇
  1968年   5篇
排序方式: 共有946条查询结果,搜索用时 15 毫秒
1.
2.
3.
In January 1990, a registry was initiated for surveillance of infants with the often severe symptoms of congenital cytomegalovirus (CMV) disease. In the first 2 years, 100 cases were reported to the registry. Petechiae, the most commonly noted clinical sign, were reported for approximately 50% of infants, usually accompanied by hepatomegaly and splenomegaly. Of the various severe neurologic conditions that can result from congenital CMV infection, the most frequent was intracranial calcifications, which were noted in 43% of the cases. The most common laboratory abnormality was low platelet count, which was observed in 52% of the cases. Infants with severe neurologic damage were about twice as likely as infants with less severe damage to have most other clinical signs and laboratory abnormalities. Databases will be developed to facilitate comparisons among symptomatically infected infants and asymptomatically infected as well as noninfected infants.  相似文献   
4.
Although there are several forces driving changes with regard to parents within neonatal intensive care units (NICUs), they all culminate in the ideals represented in family-centered care. This article examined the variables that are perceived by parents to be barriers to their assumption of parental roles while their infants were hospitalized in the NICU. Data were used to support and implement pragmatic changes in program development and service delivery within the NICU.  相似文献   
5.
6.
Summary— In the present study we have compared the steady state biopharmaceutic characteristics of four diltiazem once daily controlled release capsules: Mono-Tildiem LP 300® (300 mg), Adizem® XL (300 mg)1, Cardizem® (300 mg) and Dilacor® (240 mg). Sixteen healthy male volunteers (aged 22.9 ± 3.3 years, range 19–31 years) completed an open label, multiple oral dose, randomized, four-period crossover study without a washout period in between. The volunteers received each diltiazem formulation once daily for four days. Trough diltiazem and metabolites plasma concentrations were determined on days 3 and 4. The 24-h plasma concentration-time profiles were assessed after the dose on day 4 of each period. The following steady state pharmacokinetic parameters for diltiazem were calculated: the minimum plasma concentration (cmin), the maximum plasma concentration (cmax), the time to reach that concentration (tmax), the time interval during which the plasma concentration exceeds 50% of cmax (t50), the area under the plasma concentration-time curve (AUC72–96) and the peak-to-trough fluctuation (PTF). For the metabolites of diltiazem, N-mono-desmethyl-diltiazem (NDM) and desacetyldiltiazem (DAD), AUC72–96 (AUCNDM and AUCDAD) and the ratio metabolite/parent compound were calculated. Steady state was achieved on day 3. Except one, all controlled release formulations have satisfactory controlled release properties allowing once daily administration. However, significant (P < 0.05) differences were found between the pharmacokinetic characteristics which do not allow exchange of the various formulations. Concentrations well below 50 ng·mL-1 in the morning hours were observed for Dilacor® (240 mg) and Adizem® XL (300 mg), which could be a disadvantage of these formulations as it is well-known that ischaemic events occur at a higher rate during that part of the day. The plasma concentration profiles of NDM and DAD, the major circulating metabolites, parallel the plasma concentration profiles for the parent compound. From a clinical point of view, all treatments were well tolerated.  相似文献   
7.
Intestinal obstruction proximal to a transition zone without an interposed physical barrier usually indicates Hirschsprung disease. The authors report one case of focal small bowel muscular thinning just distal to a transition zone that produced clinical and radiographic findings that simulated long-segment Hirschsprung disease in a 2-day-old infant.  相似文献   
8.
A case of previously diagnosed bipolar disorder was found to be associated with unilateral subcortical grey matter heterotopia, cortical hemiatrophy, midline shift, and ventriculomegaly on magnetic resonance imaging (MRI). The patient responded to pharmacotherapy with lithium carbonate and carbamazepine. This case dramatically illustrates the need for neuroimaging in psychiatric patients with apparently "functional" affective illness.  相似文献   
9.
A method is described for the determination of pipothiazine in human plasma, based on reversed-phase HPLC. The method has been applied in a pharmacokinetic study of pipothiazine in six psychiatric patients receiving repeated depot intramuscular injections for six months. A number of compounds likely to be taken concurrently by patients were tested for potential to interfere with the assay. There was no evidence of "dose-dumping" in the period following injection. Comparison of the pharmacokinetic profiles after the first and sixth injections showed no evidence of drug accumulation.  相似文献   
10.
Recently, in-vitro maturation (IVM) of immature human oocytes recovered from non-stimulated follicles has been applied in the treatment of infertility. However, in previous reports, very few embryos cultured in conventional medium have reached the expanded blastocyst stage following in-vitro maturation and fertilization (IVM/IVF). The objective of this study was to investigate whether the developmental competence of human embryos following IVM/IVF could be enhanced by the use of a human ampullary cell co-culture system. Immature human oocytes were aspirated from small follicles at Caesarean section and then cultured in medium containing human menopausal gonadotrophin for 36 to 48 h, followed by insemination. Zygotes were randomly cultured either in conventional culture medium alone or in the co-culture system. Of 48 embryos cultured in conventional medium alone, all arrested at the 2-16- cell stage on day 3 after insemination. Of 46 embryos cultured in the co-culture system, 26 embryos (56.5%) arrested at the 2-16-cell stage. Six embryos (13%) developed to the morula stage. Fourteen embryos (30.4%) developed to expanded blastocysts and two blastocysts were hatching on day 7 after insemination. We conclude that co-culture significantly enhances the development of blastocysts in embryos resulting from IVM/IVF.   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