全文获取类型
收费全文 | 119篇 |
免费 | 8篇 |
专业分类
127篇 |
出版年
2021年 | 1篇 |
2019年 | 1篇 |
2017年 | 1篇 |
2016年 | 4篇 |
2015年 | 7篇 |
2014年 | 6篇 |
2013年 | 2篇 |
2011年 | 5篇 |
2010年 | 4篇 |
2009年 | 6篇 |
2008年 | 3篇 |
2007年 | 7篇 |
2006年 | 5篇 |
2005年 | 5篇 |
2004年 | 9篇 |
2003年 | 4篇 |
2002年 | 1篇 |
2001年 | 6篇 |
2000年 | 6篇 |
1999年 | 5篇 |
1998年 | 6篇 |
1997年 | 1篇 |
1996年 | 3篇 |
1995年 | 2篇 |
1994年 | 1篇 |
1992年 | 1篇 |
1991年 | 2篇 |
1990年 | 1篇 |
1989年 | 3篇 |
1988年 | 3篇 |
1987年 | 1篇 |
1985年 | 2篇 |
1984年 | 4篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1981年 | 2篇 |
1979年 | 1篇 |
1977年 | 2篇 |
1976年 | 1篇 |
1968年 | 1篇 |
排序方式: 共有127条查询结果,搜索用时 11 毫秒
61.
JS Agerholm O Andersen MB Almskou C Bendixen J Arnbjerg GP Aamand US Nielsen F Panitz AH Petersen 《Acta veterinaria Scandinavica》2004,45(3):133
To investigate the congenital complex vertebral malformation syndrome (CVM) in Holstein calves, two breeding studies were
performed including 262 and 363 cows, respectively. Cows were selected from the Danish Cattle Database based on pedigree and
insemination records. Selected cows were progeny of sires with an established heterozygous CVM genotype and pregnant after
insemination with semen from another sire with heterozygous CVM genotype. Following calving the breeders should state, if
the calf was normal and was requested to submit dead calves for necropsy. In both studies, significantly fewer CVM affected
calves than expected were obtained; a finding probably reflecting extensive intrauterine mortality in CVM affected foetuses.
The findings illustrate increased intrauterine mortality as a major potential bias in observational studies of inherited disorders. 相似文献
62.
A cascading system of hierarchical, artificial neural networks (named PRED-CLASS) is presented for the generalized classification of proteins into four distinct classes-transmembrane, fibrous, globular, and mixed-from information solely encoded in their amino acid sequences. The architecture of the individual component networks is kept very simple, reducing the number of free parameters (network synaptic weights) for faster training, improved generalization, and the avoidance of data overfitting. Capturing information from as few as 50 protein sequences spread among the four target classes (6 transmembrane, 10 fibrous, 13 globular, and 17 mixed), PRED-CLASS was able to obtain 371 correct predictions out of a set of 387 proteins (success rate approximately 96%) unambiguously assigned into one of the target classes. The application of PRED-CLASS to several test sets and complete proteomes of several organisms demonstrates that such a method could serve as a valuable tool in the annotation of genomic open reading frames with no functional assignment or as a preliminary step in fold recognition and ab initio structure prediction methods. Detailed results obtained for various data sets and completed genomes, along with a web sever running the PRED-CLASS algorithm, can be accessed over the World Wide Web at http://o2.biol.uoa.gr/PRED-CLASS. 相似文献
63.
64.
Chorion, the major component of silkmoth eggshell, consists of the A and B classes of low-molecular weight structural proteins. Chorion protects the oocyte and the developing embryo from environmental hazards and this is due to the extraordinary physical and chemical properties of its constituent proteins. We have shown previously [FEBS Lett. 479 (2000) 141; 499 (2001) 268] that peptide-analogues of the A and B classes of chorion proteins form amyloid fibrils under a variety of conditions, which led us to propose that silkmoth chorion is a natural, protective amyloid. In this work, we present data showing conclusively that, the first main step of amyloid-like fibrillogenesis of chorion peptides is the formation of nuclei of liquid crystalline nature, which is reminiscent of spider-silk formation. We show that these liquid-crystalline nuclei (spherulites) 'collapse'/deteriorate to form amyloid fibrils in a spectacular manner, important, it seems, for chorion morphogenesis and amyloid fibrillogenesis in general. The molecular 'switch' causing this spectacular transformation is, most probably, a conformational transition to the structure of chorion peptides, from a left-handed parallel beta-helix to an antiparallel beta-pleated sheet. Apparently, these peptides were suitably designed to play this role, after millions of years of molecular evolution. 相似文献
65.
Iconomidou VA Chryssikos DG Gionis V Pavlidis MA Paipetis A Hamodrakas SJ 《Journal of structural biology》2000,132(2):112-122
FT-Raman spectroscopy and ATR-IR spectroscopy were applied to study the secondary structure of the eggshell (chorion) proteins of the teleostean fish Dentex dentex. Raman and IR spectra clearly indicate an abundance of antiparallel beta-pleated sheet conformation in chorion proteins. This finding is further supported by analysis of the vibrational data by regression techniques and deconvolution procedures. Thus, the common morphological characteristics of D. dentex, Salmo gairdneri, and other teleostean fish chorions may be explained on the basis of common secondary structure features of their constituent proteins. A detailed understanding of the interactions that dictate the self-assembly of fish chorion proteins to form the fish eggshell awaits determination of amino acid sequences. 相似文献
66.
Ganesh Kumar Veeramachaneni K Kranthi Raj Leela Madhuri Chalasani Sai Krishna Annamraju Bondili JS Venkateswara Rao Talluri 《Bioinformation》2015,11(12):535-542
Increase in obesity rates and obesity associated health issues became one of the greatest health concerns in the present world
population. With alarming increase in obese percentage there is a need to design new drugs related to the obesity targets. Among
the various targets linked to obesity, pancreatic lipase was one of the promising targets for obesity treatment. Using the in silico
methods like structure based virtual screening, QikProp, docking studies and binding energy calculations three molecules namely
zinc85531017, zinc95919096 and zinc33963788 from the natural database were reported as the potential inhibitors for the pancreatic
lipase. Among them zinc95919096 presented all the interactions matching to both standard and crystal ligand and hence it can be
further proceeded to drug discovery process. 相似文献
67.
R Martin DS Buchan JS Baker J Young N Sculthorpe FM Grace 《Biology of sport / Institute of Sport》2015,32(4):307-313
The present study examined the physiological impact of a school based sprint interval training (SIT) intervention in replacement of standard physical education (SPE) class on cardio-respiratory fitness (CRF) and glucose homeostasis during the semester following summer vacation. Participants (n=49) were randomly allocated to either intervention (SIT; n=26, aged 16.9 ± 0.3 yrs) or control group who underwent standard physical education (SPE; n=23, aged 16.8 ± 0.6 yrs). CRF (VO2max) and glucose homeostasis were obtained prior-to and following 7 weeks of SIT exercise. Significant group x time interaction was observed for CRF (P < 0.01) with non-significant trends for fasting insulin (P= 0.08), and HOMA-IR (P=0.06). CRF decreased (P < 0.01) in SPE such that POST intervention CRF was significantly lower (P< 0.05) in SPE. Fasting plasma glucose (P < 0.01), insulin (P< 0.01) and HOMA-IR (P< 0.01) increased significantly amongst SPE. The main finding of the present study is that 7-weeks of SIT exercise is an effective method of maintaining (but not improving) CRF and fasting insulin homeostasis amongst school-going adolescents. SIT exercise demonstrates potential as a time efficient physiological adjunct to standard PE class in order to maintain CRF during the school term. 相似文献
68.
69.
70.
Andrew JS Coats 《Trials》2000,1(3):155-6
Chronic heart failure (CHF) is a common condition with a poor prognosis. It is associated with poor exercise tolerance and debilitating symptoms. These symptoms appear to be associated with pathophysiological changes that occur systemically in the patient with CHF. Exercise training in carefully selected patients has been shown to be safe and to improve exercise capacity. Many of the pathophysiological abnormalities of CHF are improved by training. Some studies have suggested a possible improvement in morbidity and mortality with training. This review analyzes the controlled clinical trials of exercise training in CHF published to date. 相似文献