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   77篇
  免费   19篇
儿科学   1篇
妇产科学   2篇
基础医学   29篇
口腔科学   4篇
临床医学   5篇
内科学   18篇
皮肤病学   2篇
神经病学   6篇
特种医学   1篇
外科学   7篇
综合类   2篇
预防医学   15篇
眼科学   1篇
药学   1篇
中国医学   2篇
  2022年   1篇
  2021年   1篇
  2020年   2篇
  2019年   1篇
  2018年   1篇
  2017年   4篇
  2016年   2篇
  2015年   4篇
  2014年   3篇
  2013年   3篇
  2012年   5篇
  2011年   11篇
  2010年   5篇
  2009年   3篇
  2008年   2篇
  2007年   2篇
  2006年   3篇
  2005年   4篇
  2004年   3篇
  2003年   1篇
  2002年   3篇
  2001年   1篇
  2000年   1篇
  1999年   5篇
  1998年   2篇
  1996年   1篇
  1994年   6篇
  1992年   3篇
  1991年   1篇
  1990年   4篇
  1989年   4篇
  1988年   1篇
  1987年   1篇
  1982年   1篇
  1979年   1篇
排序方式: 共有96条查询结果,搜索用时 31 毫秒
11.
12.
The relationship among G3P5A rotavirus strains was analysed by restriction endonuclease assay of the VP4, VP6 and VP7 encoding genes, neutralization assay and phylogenetic analysis. The restriction patterns of the capsid encoding genes were species specific allowing the differentiation among the strains of different origin. The VP7 profiles differentiated human from animal strains more efficiently. The phylogenetic analysis of the VP4 gene demonstrated that HCR3A and K9 are closer related to each other than to other P5A strains. The same occurs to strains Ro1845 and Cat 97. The CU-1 virus appears to be an ancestor of the P5A strains by neutralization and phylogenetic analysis. The results placed the RRV strain definitely in a separate VP4 serotype and genotype from that of P5A strains. Restriction endonuclease assay of the capsid encoding genes seems to be a useful tool to identify the host species of rotavirus strains belonging to the same serotype and/or genotype.  相似文献   
13.
14.
An 8-year-old black boy with sickle cell disease and severe hemolytic anemia crisis (95% hemoglobin S) also had mitral incompetence due to rheumatic valve disease. A 27 mm monostrut Bj?rk-Shiley valve prosthesis was implanted after partial exchange transfusions had reduced the hemoglobin S to less than 40%. High-flow normothermic perfusion was used during extracorporeal circulation, with care taken to avoid hypoxia and acidosis. Postoperative recovery was uneventful.  相似文献   
15.
Six avian reovirus isolates and a vaccine reovirus strain were compared for invasiveness, virulence, and pathological characteristics upon infection of day-old specific-pathogen-free chicks by the footpad, subcutaneous, and oral routes of inoculation. No significant differences were noted regarding the ability of individual isolates to infect target tissues. However, virulence (measured as the 50% lethal dose) among the isolates varied markedly from 2 x 10(5) to less than 10 PFU per chick for the most virulent isolate; between the parental wild-type virus and the derivative vaccine virus strain, a million-fold (10(6)) difference in virulence was demonstrated. All strains revealed, with considerable variation, arthrogenic potential.  相似文献   
16.
Aberrant crypt foci (ACF) and colon rectal mucosal epithelial cell proliferation have been shown to be increased in patients with colon cancer and have been largely used for early detection of factors that influence colorectal carcinogenesis in rats. Fifty male Wistar rats were randomly divided into 5 groups. The groups G1 to G4 were given 4 injections of the carcinogen 1,2-dimethylhydrazine (DMH). The G2 group received Lychnophora ericoides (LE) extracts for 6 wk. The groups G3 and G4 received LE for 4 wk and 2 wk, respectively, at the postinitiation and initiation phases of colonic carcinogenesis. The group G5 was the control. Forty-two days after the first injections of DMH for the neoplasic induction, we observed a statistically significant decrease in the number of aberrant crypt foci (ACF) and an attenuation of the increase in cell proliferation induced by DMH in all the LE-treated groups. Thus, we concluded that Lychnophora ericoides extracts were effective against the development of cancer. These data suggest that LE has a protective influence on the process of colon carcinogenesis, suppressing both the initiation and the promotion of colonic carcinogenesis.  相似文献   
17.
Mutations in the GJB1 gene are the second most frequent cause of Charcot‐Marie‐Tooth disease (CMT), accounting for approximately 10% of CMT cases worldwide. We retrospectively analyzed detailed clinical and neurophysiological data on four Brazilian families carrying novel mutations of the GJB1 gene. Mutations were identified by bidirectional Sanger sequence analysis on the GJB1 coding region. We identified a total of 12 subjects from four different kindred. There was no male‐to‐male transmission, and their clinical pictures were within the expected spectrum for GJB1‐related neuropathy. Males were more severely affected than females. Five out of the eight females only had subclinical neuropathy. Nerve conduction velocities were in the intermediate range in the male patients and higher in the females affected. These mutations increase the genotypic variability associated with GJB1.  相似文献   
18.
The aim of this study was to investigate the effect of imagining an action implicating the body axis in the kinesthetic and visual motor imagery modalities upon the balance control system. Body sway analysis (measurement of center of pressure, CoP) together with electromyography (EMG) recording and verbal evaluation of imagery abilities were obtained from subjects during four tasks, performed in the upright position: to execute bilateral plantar flexions; to imagine themselves executing bilateral plantar flexions (kinesthetic modality); to imagine someone else executing the same movement (visual modality), and to imagine themselves singing a song (as a control imagery task). Body sway analysis revealed that kinesthetic imagery leads to a general increase in CoP oscillation, as reflected by an enhanced area of displacement. This effect was also verified for the CoP standard deviation in the medial–lateral direction. An increase in the trembling displacement (equivalent to center of pressure minus center of gravity) restricted to the anterior–posterior direction was also observed to occur during kinesthetic imagery. The visual imagery task did not differ from the control (sing) task for any of the analyzed parameters. No difference in the subjects' ability to perform the imagery tasks was found. No modulation of EMG data were observed across imagery tasks, indicating that there was no actual execution during motor imagination. These results suggest that motor imagery performed in the kinesthetic modality evokes motor representations involved in balance control.  相似文献   
19.
Reaction of n-butyltin trichloride [(n-Bu)SnCl(3)] with 2-pyridineformamide thiosemicarbazone (H2Am4DH) and its N(4)-methyl (H2Am4Me) and N(4)-ethyl (H2Am4Et) derivatives gave [(n-Bu)Sn(2Am4DH)Cl(2)] (1), [(n-Bu)Sn(2Am4Me)Cl(2)] (2), and [(n-Bu)Sn(2Am4Et)Cl(2)] (3). Thiosemicarbazones as well as their tin complexes are active as antimicrobials against the growth of Candida albicans and Salmonella typhimurium and were highly active against malignant glioblastoma. The cytotoxic activity of complexes 1-3 is similar. Among the studied compounds [(n-Bu)Sn(2Am4DH)Cl(2)] (1) was the most active as antiproliferative (cytostatic) agent. Thiosemicarbazones and their tin(IV) complexes proved to be more potent as cytotoxic agents than cisplatin. All the compounds were able to induce apoptosis.  相似文献   
20.
Lambert-Eaton myasthenic syndrome (LEMS) is a neurological autoimmune disease in which downregulation of voltage-gated calcium channels (VGCCs) leads to reduced acetylcholine release from motoneuron terminals. 70% of cases are paraneoplastic and rapid diagnosis of LEMS can result in early detection of the underlying tumor. Serological assays based on the capacity of autoantibodies to precipitate VGCCs labeled with radioligands provide valuable data. We have established a novel assay using the spider venom peptide 125I-omega-Phonetoxin IIA (125I-omegaPtxIIA). 125I-omegaPtxIIA labeled recombinant Cav2.1 and Cav2.2 channels and endogenous VGCCs in rat brain membranes. Autoantibodies that immunoprecipitate a 125I-omegaPtxIIA/channel complex were detected in 26/31 (84%) LEMS patients. The patients that were seropositive in the 125I-omegaPtxIIA assay corresponded precisely to the population that was positive for Cav2.1 and/or Cav2.2 antibodies detected using two different omega-conotoxins. Thus, the 125I-omegaPtxIIA assay detects a broader spectrum of autoantibody specificities than current omega-conotoxin-based assays.  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