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   330篇
  免费   6篇
  国内免费   1篇
耳鼻咽喉   18篇
儿科学   38篇
妇产科学   4篇
基础医学   36篇
口腔科学   9篇
临床医学   56篇
内科学   47篇
皮肤病学   4篇
神经病学   6篇
特种医学   26篇
外科学   30篇
综合类   24篇
预防医学   14篇
眼科学   1篇
药学   16篇
中国医学   4篇
肿瘤学   4篇
  2021年   3篇
  2019年   7篇
  2017年   2篇
  2016年   1篇
  2015年   5篇
  2014年   25篇
  2013年   22篇
  2012年   13篇
  2011年   8篇
  2010年   11篇
  2009年   14篇
  2008年   5篇
  2007年   9篇
  2006年   10篇
  2005年   5篇
  2004年   4篇
  2003年   9篇
  2002年   7篇
  2001年   4篇
  2000年   8篇
  1999年   4篇
  1998年   13篇
  1997年   18篇
  1996年   11篇
  1995年   9篇
  1994年   10篇
  1993年   12篇
  1992年   2篇
  1991年   4篇
  1990年   5篇
  1989年   3篇
  1988年   2篇
  1987年   1篇
  1986年   3篇
  1985年   1篇
  1984年   3篇
  1983年   2篇
  1981年   2篇
  1980年   1篇
  1979年   1篇
  1978年   4篇
  1977年   1篇
  1976年   1篇
  1958年   1篇
  1957年   2篇
  1956年   2篇
  1954年   2篇
  1952年   16篇
  1951年   23篇
  1950年   2篇
排序方式: 共有337条查询结果,搜索用时 0 毫秒
11.
A 57-year-old-man with a history of malaise, fever,night sweats and shortness of breath presented a diagnostic challenge to his medical team. He was pancytopaenic and had splenomegaly on admission but other investigations, including bone marrow aspiration, proved inconclusive. After the patient deteriorated clinically, the general surgical team was requested to perform a diagnostic splenectomy. The histology of this showed infection with visceral leishmaniasis. He recovered completely with Amphotericin treatment. Although this is a rare condition, particularly for the general surgeon, this case highlights the difficult position surgeons are often put in when performing major surgery diagnostically.  相似文献   
12.
Australia has a large migrant population with variable fluency in English. Interpreting services help ensure that healthcare services are delivered appropriately to these populations. However, the use of professional interpreters in hospitals is expensive. There are also issues with service availability and convenience. Mobile devices containing software with translating abilities have promising potential to improve communication between patients and hospital staff as an adjunct to professional interpreters. It is highly convenient and inexpensive. There are concerns about the accuracy of the interpretation done with such software and more research needs to be carried out to support or allay these concerns. For now, clinically important and medicolegal related interpretation should be undertaken by professional interpreters whereas less crucial tasks may be performed with the help of interpreting software on mobile devices.  相似文献   
13.

Background

The extent to which GPs serve as a reservoir for antibiotic-resistant Staphylococcus aureus is unknown and not well studied.

Aim

To determine the prevalence of nasal S. aureus carriage among GPs in the Netherlands, as well as the antimicrobial resistance and the genotypes of isolated S. aureus.

Design of study

Observational, point-prevalence, and cross-sectional study.

Setting

GPs attending the annual conference of the Dutch College of General Practitioners in 2006.

Method

Nasal swabs were randomly taken from 395 GPs and analysed for the presence of S. aureus. Antimicrobial susceptibility was determined by a microbroth dilution method and the genotypes by spa typing, which was associated with multilocus sequence typing.

Results

Of the GPs, 129/395 (33%; 95% confidence interval [CI] = 28 to 37%) were carriers of S. aureus. No meticillin-resistant S. aureus (MRSA) was found. Resistance was observed to penicillin (71%; 95% CI = 63 to 79%), fusidic acid (7%; 95% CI = 3 to 13%), and clarithromycin (6%; 95% CI = 3 to 12%). In 72% of the isolates, an MRSA-related genotype of S. aureus was found.

Conclusion

The low antibiotic resistance found among S. aureus of GPs suggests that GPs are not a reservoir of antibiotic-resistant S. aureus strains. The relatively high resistance to fusidic acid, which has not previously been described in the Netherlands and is mostly because of antibiotic use, suggests that patients infect GPs and not the other way round. GPs may be at risk for nasal carriage of S. aureus with an MRSA-related genotype.  相似文献   
14.
Lung carcinoids occur sporadically and rarely in association with multiple endocrine neoplasia type 1 (MEN1). There are no well defined genetic abnormalities known to occur in these tumors. We studied 11 sporadic lung carcinoids for loss of heterozygosity (LOH) at the locus of the MEN1 gene on chromosome 11q13, and for mutations of the MEN1 gene using dideoxy fingerprinting. Additionally, a lung carcinoid from a MEN1 patient was studied. In four of 11 (36%) sporadic tumors, both copies of the MEN1 gene were inactivated. All four tumors showed the presence of a MEN1 gene mutation and loss of the other allele. Observed mutations included a 1 bp insertion, a 1 bp deletion, a 13 bp deletion and a single nucleotide substitution affecting a donor splice site. Each mutation predicts truncation or potentially complete loss of menin. The remaining seven tumors showed neither the presence of a MEN1 gene mutation nor 11q13 LOH. The tumor from the MEN1 patient showed LOH at chromosome 11q13 and a complex germline MEN1 gene mutation. The data implicate the MEN1 gene in the pathogenesis of sporadic lung carcinoids, representing the first defined genetic alteration in these tumors.   相似文献   
15.
Superoxide, an agent which attenuates the half-life of nitric oxide, is metabolized and synthesized by superoxide dismutase (SOD) and xanthine oxidase, respectively. Over the last few years much work has focused on the role of nitric oxide in human parturition. The aim of this study was to determine whether the onset of human parturition is associated with a change in the expression of copper/zinc superoxide dismutase (Cu/Zn SOD), manganese superoxide dismutase (Mn SOD) or xanthine oxidase within the uterus. Samples of myometrium, placenta, decidua and fetal membranes were obtained from women before and after the onset of labour at term. Immunocytochemistry was used to localize Cu/Zn SOD, Mn SOD and xanthine oxidase and measure SOD enzyme activity. Cu/Zn and Mn SOD-like immunoreactivity was detected in syncytiotrophoblast cells, villous stromal cells and endothelial cells of blood vessels in the placenta. In the myometrium Cu/Zn and Mn SOD were localized to myocytes and endothelial cells and to some vascular smooth muscle cells. In the fetal membranes we observed staining for Cu/Zn SOD and Mn SOD in the amnion, chorion, extravillous trophoblast and decidua. There was no difference in SOD enzyme activity or staining intensity for SOD between different cell types before and during labour. Xanthine oxidase immunoreactivity was identified in each of the tissues examined and again there was no difference in immunostaining in tissues obtained from women delivered before or after the onset of labour. These results show that the pregnant uterus is capable of both synthesizing and degrading superoxide and suggest that superoxide dismutase and xanthine oxidase may play a role in the maintenance of uterine quiescence during pregnancy, but not in the initiation of parturition.   相似文献   
16.
目的探讨多聚(ADP-核糖)聚合酶(PARP)抑制剂3-氨基苯甲酰胺(3-AB)在大鼠-肾脏缺血再灌注损伤中的保护作用及对肾组织血管内皮生长因子A(VEGF-A)和中性粒细胞明胶酶相关脂质运载蛋白(NGAL)mRNA表达的影响。方法将54只大鼠随机分为假手术组(S组)、再灌注后模型组(M组)和PARP抑制剂组(P组),每组8只。比较各组大鼠右侧肾动脉缺血再灌注后2、6、12h后的血肌酐和尿素氮水平、肾脏组织病理学变化、肾组织PARP蛋白表达及肾组织VEGF-A和NGAI.mRNA表达。结果(1)M组各时间点的血肌酐、尿素氮水平均高于S组,P组各时间点血肌酐、尿素氮明显低于M组,差异均有统计学意义(P〈0.01);(2)P组肾组织病理学表现较M组改善;(3)P组各时间点肾组织PARP表达明显低于M组,差异有统计学意义(P〈0.05);(4)与M组相比,P组肾组织的VEGF-AmRNA的表达升高,NGALmRNA表达降低,有统计学差异(P〈0.05)。结论PARP抑制剂3AB对大鼠肾脏缺血再灌注损伤具有保护作用,可下调NGAL及上调VEGF-AmRNA表达。  相似文献   
17.
Atlanto-axial rotatory fixation (AARF) is an uncommon condition which is often missed at presentation because of its rarity and the relative subtlety of plain film X-ray findings, but early detection and appropriate management are vital for a cure. We describe three cases in which the use of spiral computed tomography scanning with 3D and sagittal reconstructions greatly aided diagnosis and management. The 3D images gave a more graphic picture of the overall alignment of the upper cervical spine and the skull base, while the sagittal reconstructions demonstrated the presence or absence of compensatory atlanto-occipital subluxation. The literature is briefly reviewed.  相似文献   
18.
The partial androgen insensitivity syndrome occurs in 46,XY subjects with phenotypes ranging from perineoscrotal hypospadias with cryptorchidism and micropenis (mild undervirilisation) to clitoromegaly and partial labial fusion (marked undervirilisation). Within an affected family, wide variation in the degree of genital ambiguity between individuals can be seen. Two cousins of a previously reported subject who had severe genital ambiguity and partial androgen insensitivity were investigated. Neither of the cousins had genital abnormalities as marked as the index case, who also had qualitatively abnormal androgen binding and two mutations of the androgen receptor gene. Despite marked phenotypic differences between the index case and his cousins, similar androgen binding and the same androgen receptor mutations were shown in the cousins. Furthermore, one of the androgen receptor gene mutations has been shown in the mother and sister of one of the boys indicating that they are carriers. Thus phenotypic variation in families affected by partial androgen insensitivity is dependent on factors other than abnormalities of the androgen receptor gene alone. Although carrier status in partial androgen insensitivity can be determined, the severity of genital abnormalities in an affected offspring cannot be reliably predicted.  相似文献   
19.
20.
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