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   676篇
  免费   33篇
  国内免费   2篇
耳鼻咽喉   14篇
儿科学   17篇
妇产科学   11篇
基础医学   103篇
口腔科学   20篇
临床医学   76篇
内科学   137篇
皮肤病学   10篇
神经病学   54篇
特种医学   8篇
外科学   32篇
预防医学   57篇
眼科学   53篇
药学   44篇
中国医学   3篇
肿瘤学   72篇
  2024年   1篇
  2023年   24篇
  2022年   24篇
  2021年   48篇
  2020年   31篇
  2019年   29篇
  2018年   27篇
  2017年   21篇
  2016年   22篇
  2015年   13篇
  2014年   31篇
  2013年   32篇
  2012年   58篇
  2011年   56篇
  2010年   33篇
  2009年   30篇
  2008年   42篇
  2007年   30篇
  2006年   37篇
  2005年   38篇
  2004年   24篇
  2003年   14篇
  2002年   16篇
  2001年   1篇
  1999年   4篇
  1998年   4篇
  1997年   2篇
  1996年   2篇
  1995年   4篇
  1994年   3篇
  1993年   2篇
  1989年   1篇
  1982年   2篇
  1978年   2篇
  1975年   1篇
  1973年   1篇
  1971年   1篇
排序方式: 共有711条查询结果,搜索用时 296 毫秒
61.
62.
Acquisition of respiratory pathogens such as Pseudomonas aeruginosa (PA) is associated with increased morbidity and mortality in cystic fibrosis (CF). Research on the prevalence of these pathogens on environmental surfaces of a CF Center is scanty, and so far no study has determined what risk CF patients have of coming in contact with them during their visits to the CF Center. This study is aimed at assessing the prevalence of some respiratory pathogens in samples taken systematically during a 4-year period from inanimate surfaces and sinks in a CF Outpatient Clinic, and to estimate the risk that a non-PA colonized CF patient has of contact with PA when visiting the CF Center. Microbiological samples were taken and cultured from the inanimate surfaces and sinks of the Outpatient clinic of a CF Center once a month from 2001 to 2005. Four hundred and sixty environmental specimens were collected: 36.3% were positive for respiratory pathogens (23% of rooms' inert surfaces, 49.5% of sinks). Achromobacter xylosoxidans was found in 0.8% of surface samples. PA was isolated in 22.8% samples. The estimated risk for each non-colonized patient of coming in contact with PA on the surfaces in the Clinic at each visit was 5.4 per thousand (CI95% 0.9-30.1). Genotyping of a sample of environmental PA strains revealed a genetic relation between environmental and clinical isolates in most cases. Micro-organisms relevant for CF patients can be found on inanimate surfaces of a CF Center, although the risk for patients of coming in contact with PA during their visits to the CF center seems low.  相似文献   
63.
In a search for novel antileishmanial drugs, we investigated the activity of the calcium channel blocker nimodipine against Leishmania spp. and explored the ultrastructural damages of parasites induced by nimodipine after a short period of incubation. Nimodipine was highly effective against promastigotes and intracellular amastigotes of Leishmania (L.) chagasi, with 50% inhibitory concentration values of 81.2 and 21.5 μM, respectively. Nimodipine was about fourfold more effective than the standard pentavalent antimony against amastigotes and showed a Selectivity Index of 4.4 considering its mammalian cells toxicity. Leishmania (L.) amazonensis and Leishmania (L.) major promastigotes were also susceptible to nimodipine in a range concentration between 31 and 128 μM. Ultrastructural studies of L. (L.) chagasi revealed intense mitochondria damage and plasma membrane blebbing, resulting in a leishmanicidal effect as demonstrated by the lack of mitochondrial oxidative metabolism. The amastigote-killing effect suggests other mechanism than macrophage activation, as no upregulation of nitric oxide was seen. This calcium channel blocker is an effective in vitro antileishmanial compound and if adequately studied could be used as a novel drug candidate or as a novel drug lead compound for drug design studies against leishmaniasis.  相似文献   
64.
Human papillomavirus (HPV) are distributed widely and persistent infection with high‐risk (HR) HPV is recognized as a necessary cause of cervical cancer. The aim of this study was to evaluate the distribution of different HR‐HPV genotypes in 199 women with cervical pre‐invasive lesions undergoing conservative treatment. A Linear Array HPV Genotyping Test was used to identify individual HPV genotypes in cervical samples. It was observed that the most prevalent HPV genotypes were HPV 16 (52.6%), HPV 51 (13.5%), and HPV 31 (10.9%); HPV 18 was found in 7.3% of the patients. Stratifying the different HPV genotypes according to the severity of the cervical lesion, a strong association between the increasing severity of the histological diagnosis and the detection of more carcinogenic HR‐HPV type was found, and in all but one cervical intraepithelial neoplasia of grade 3 the presence of at least one HR‐HPV could be detected, with more than 70% of cervical intraepithelial neoplasia of grade 3 patients bearing HPV 16. Multiple infections, comprising between 2 and 6 HPV types, were found in 43% of patients; however, the presence of more than 1 HR‐HPV type was not associated with an increased risk of high grade lesions. In conclusion, this data show that HPV 16, 51, 31, 52, and 18 were the prevalent types found in patients with cervical lesion undergoing conservative treatment, with a high prevalence of HPV 16 in cervical intraepithelial neoplasia of grade 3 patients. No association between multiple infection and severity of the lesion could be found. J. Med. Virol. 81:271–277, 2009. © 2008 Wiley‐Liss, Inc.  相似文献   
65.
The complete genomes of three Czech isolates VIRUBRA 1/045, VIRUBRA 1/046, and VIRUBRA 1/047 of Potato leafroll virus (PLRV) were sequenced and compared with 13 complete sequences of PLRV isolates available in GenBank. Among the Czech isolates, VIRUBRA 1/046 and 1/047 showed the highest nucleotide (nt) identity (98.7%). PLRV was the most conserved virus in both open reading frames (ORFs) 3 and 4. The most variable regions were ORFs 0 and Rap1. Interestingly, isolate VIRUBRA 1/045 significantly differed from the other two Czech isolates in ORFs 0 and 1. Moreover, we identified mutations in the amino acid (aa) sequences, which were specific for the Czech isolates. Phylogenetic analysis based on ORF0 showed that the Czech isolates could be classified in two of the three groupings of the phylogenetic tree obtained. This is the first report on sequence analysis of the genome sequences of PLRV isolates from the Czech Republic. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
66.
The factors involved in the pathogenesis of Crohn’s disease and ulcerative colitis, the two major types of inflammatory bowel disease (IBD) are summarized. Intestinal antigens composed of bacterial flora along with antigen presentation and impaired mucosal barrier have an important role in the initiation of IBD. The bacterial community may be modified by the use of antibiotics and probiotics. The dentritic cells recognize the antigens by cell surface Toll like receptor and the cytoplasmic CARD/NOD system. The balance between Th1/Th2/Th17 cell populations being the source of a variety of cytokines regulates the inflammatory mechanisms and the clearance of microbes. The intracellular killing and digestion, including autophagy, are important in the protection against microbes and their toxins. The homing process determines the location and distribution of the immune cells along the gut. All these players are potential targets of pharmacological manipulation of disease status.  相似文献   
67.
68.
69.

Introduction

Labia minora adhesions (LMA) are a common finding in young girls. Usually, this condition is asymptomatic and spontaneously disappears during adolescence. We report on a case revealed by infected urocolpos and peritonitis and whose treatment finally required surgical reduction labioplasty.

Case report

A 9-year-old girl presented with a 2-day history of abdominal pain and fever. Urinary continence had never been obtained, with diurnal leaks. Physical examination showed signs of peritoneal irritation and a subtotal vulvar obstruction due to LMA. At surgery, after LMA lysis, a large amount of cloudy urine-like fluid emptied under pressure from the vagina. Laparoscopy showed generalized peritonitis without any intraabdominal cause. The same Escherichia coli was identified in the infected urocolpos and the abdominal fluid. Postoperative course was uneventful.Because of recurrent LMA, the patient underwent several courses of local estrogen therapy. Labia minora hypertrophy with LMA developed 2 years after peritonitis, requiring surgical reduction labioplasty. We used a new technique with interposition of skin flaps. The girl is now well, without LMA or infection, 4 years after labioplasty.

Conclusion

Although rare, subtotal vulvar obstruction because of LMA may lead to infected hydrocolpos and peritonitis. Recurrent LMA may necessitate surgical labioplasty.  相似文献   
70.
We tested if there were any differences about nocturnal and diurnal anxiety between patients either affected by Binge Eating Disorder (BED) or Night eating Syndrome (NES). Fifty four patients affected by BED, 13 by NES and 16 by both BED and NES were tested using the Self Rating Anxiety Scale (SAS) and the Sleep Disturbance Questionnaire (SDQ). Their nocturnal eating behavior was ascertained through the Night Eating Questionnaire (NEQ). Patients affected by both BED and NES scored significantly higher on SAS than other patients. Among NES patients we found a correlation between a SDQ subscale and two subscales of the NEQ. Among BED patients we found a correlation between SAS scores and the nocturnal ingestion subscale of the NEQ. Nocturnal eating is related to nocturnal anxiety among NES patients while it is related to diurnal anxiety among patients affected by BED. These findings support the hypothesis that BED and NES are distinct syndromes sharing overeating but with different pathways to excessive food intake.  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