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   44篇
  免费   1篇
  国内免费   1篇
  2018年   1篇
  2016年   1篇
  2015年   2篇
  2014年   1篇
  2013年   2篇
  2012年   5篇
  2011年   1篇
  2010年   4篇
  2009年   3篇
  2008年   1篇
  2007年   2篇
  2006年   1篇
  2005年   3篇
  2004年   2篇
  2003年   1篇
  2002年   1篇
  1999年   2篇
  1998年   3篇
  1997年   1篇
  1996年   1篇
  1995年   1篇
  1994年   1篇
  1993年   1篇
  1992年   1篇
  1991年   1篇
  1988年   1篇
  1983年   1篇
  1977年   1篇
排序方式: 共有46条查询结果,搜索用时 15 毫秒
21.
彭金荣  孙册 《昆虫学报》1991,(2):135-140
蓖麻蚕Philosamia cynthia ricni血淋巴含两种凝集素,一种凝集兔新鲜红血球,凝血活力被L-鼠李糖和D-半乳糖抑制;另一种凝集戊二醛固定的人和鸡的红血球,凝血活力被岩藻糖抑制.它们在蚕的不同生长阶段及在蚕体各组织中的分布和凝血活力显著不同.血淋巴中这两种凝集素的凝血活力明显比其他组织中高.卵中测不到这两种凝集素活力.本文对这两种凝集素在蚕体中可能的生理功能进行了讨论.  相似文献   
22.

Background  

Estimators of free energies are routinely used to judge the quality of protein structural models. As these estimators still present inaccuracies, they are frequently evaluated by discriminating native or native-like conformations from large ensembles of so-called decoy structures.  相似文献   
23.
We compared histochemical and immunohistochemical staining as well as fluorochrome labeling in murine bone specimens that were fixed with 10% neutral buffered formalin to those fixed with HistoChoice®. We showed that sections from undecalcified tibiae fixed for 4 h in HistoChoice® resulted in enhanced toluidine blue and Von Kossa histochemical staining compared to formalin fixation. HistoChoice® produced comparable or improved staining for alkaline phosphatase. Acid phosphatase localization was better in formalin fixed specimens, but osteoclasts were visuralized more easily in HistoChoice® fixed specimens. As expected, immunohistochemical labeling was antibody dependent; some antibodies labeled better in HistoChoice® fixed specimens while others were better in formalin fixed specimens. Toluidine blue, Von Kossa, and alkaline phosphatase staining of sections fixed for 12 h produced sections that were similar to 4 h fixed sections. Fixation for 12 h preserved acid phosphatase activity better. Increasing fixation to 12 h affected immunolocalization differentially. Bone sialoprotein labeling in HistoChoice® fixed specimens was comparable to formalin fixed samples. On the other hand, after 12 h formalin fixation, osteocalcin labeling was comparable to HistoChoice®. For most histochemical applications, fixing murine bone specimens for 4 h with HistoChoice® yielded superior staining compared to formalin fixation. If immunohistochemical localization is desired, however, individual antibodies must be tested to determine which fixation process retains antigenicity better. In addition, there was no detectable difference in the intensity of fluorochrome labeling using either fixative. Finally, fixation duration did not alter the intensity of labeling.  相似文献   
24.
25.
The purpose of the study was to determine the accuracy of 11 prediction equations in estimating the 1 repetition maximum (1 RM) bench press from repetitions completed by collegiate football players (N = 69) using 225 lb. The demographic variables race, age, height, weight, fat-free weight, and percent body fat were measured to determine whether these variables increased the accuracy of the prediction equations; race was the most frequently selected variable in the regression analyses. The validity of the prediction equations was dependent upon the number of repetitions performed, i.e., validity was higher when fewer repetitions were completed. Explained variability of 1 RM was slightly higher for all 11 equations when demographic variables were included. A new prediction equation was also developed using the number of repetitions performed and the demographic variables height and fat-free weight.  相似文献   
26.

Background  

Experimentally determined protein structures may contain errors and require validation. Conformational criteria based on the Ramachandran plot are mainly used to distinguish bet ween distorted and adequately refined models. While the readily available criteria are sufficient to detect totally wrong structures, establishing the more subtle differences between plausible structures remains more challenging.  相似文献   
27.
28.

Introduction  

Though remission is currently a treatment goal in patients with rheumatoid arthritis (RA), the number of patients who achieve and sustain remission in daily practice is still small. It is suggested that early remission will be associated with sustainability of remission. The aim was to study the association between time-to-remission and sustainability of remission in a cohort of early RA patients treated according to daily practice.  相似文献   
29.
30.
ABSTRACT: BACKGROUND: Prophylaxis to prevent relapses in the central nervous system after childhood acute lymphoblastic leukemia (ALL) used to consist of both intrathecal chemotherapy (CT) and cranial irradiation (CRT). CRT was mostly abolished in the eighties because of its neurotoxicity, and replaced with more intensive intrathecal CT. In this study, a group of survivors treated with CRT before 1983 and another group treated without CRT thereafter are investigated 20--25 years later, giving a much stronger perspective on long-term quality of life than previous studies. The outcomes will help to better understand these groups' current needs and will aid in anticipating late effects of prophylactic CRT that is currently applied for other diseases.This study evaluates oscillatory neuronal activity in these long-term survivors. Power spectrum deviations are hypothesized to correlate with cognitive dysfunction. METHODS: Resting state eyes-closed magnetoencephalography (MEG) recordings were obtained from 14 ALL survivors treated with CT + CRT, 18 treated with CT alone and 35 controls. Relative spectral power was calculated in the delta, theta, alpha1, alpha2, beta and gamma frequency bands. The Amsterdam Neuropsychological Tasks (ANT) program was used to assess cognition in the executive functions domain. MEG data and ANT scores were correlated. RESULTS: In the CT + CRT group, relative theta power was slightly increased (p = 0.069) and alpha2 power was significantly decreased (p = 0.006). The CT + CRT group performed worse on various cognitive tests. A deficiency in visuomotor accuracy, especially of the right hand, could be clearly associated with the deviating regional theta and alpha2 powers (0.471 < r < 0.697). A significant association between decreased regional alpha2 power and less attentional fluctuations was found for CT + CRT patients as well as controls (0.078 < r < 0.666). Patients treated with CT alone displayed a power spectrum similar to controls, except for a significantly increased level of left frontal alpha2 power (p = 0.030). CONCLUSIONS: The tendency towards global slowing of brain oscillatory activity, together with the fact that dementia has been reported as a late effect of CRT and the neuropsychological deficiencies currently present, suggest that the irradiated brain might be aging faster and could be at risk for early onset dementia. The CT group showed no signs of early aging.  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