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排序方式: 共有919条查询结果,搜索用时 15 毫秒
41.
Singh Shweta Hans Sandeep Ahmad Aijaz Fatima Zeeshan Hameed Saif 《International microbiology》2022,25(4):769-779
International Microbiology - Infections caused by Candida albicans are rising due to increment in drug resistance and a limited arsenal of conventional antifungal drugs. Thus, elucidating the novel... 相似文献
42.
43.
Tom Z. Yuan Pankaj Garg Linya Wang Jordan R. Willis Eric Kwan Ana G Lujan Hernandez Emily Tuscano Emily N. Sever Erica Keane Cinque Soto Eric M. Mucker Mallorie E. Fouch Edgar Davidson Benjamin J. Doranz Shweta Kailasan M. Javad Aman Haoyang Li Jay W. Hooper Erica Ollmann Saphire James E. Crowe Qiang Liu Fumiko Axelrod Aaron K. Sato 《MABS-AUSTIN》2022,14(1)
44.
P P Batra 《The International journal of biochemistry》1991,23(12):1375-1384
The lysine residues were modified to varying degrees (50-91%) with citraconic anhydride to determine the extent of conformational change in ovalbumin. Major findings included: 1. Sixteen of the 20 lysine residues are located on the protein surface, while the remaining four are buried. 2. The tertiary structure changed progressively with the degree of modification. 3. However, the secondary structure was disrupted only after one or more of the four buried lysines had been citraconylated. 4. Although the secondary structure was unaltered, the alpha-helix was nevertheless progressively destabilized as the surface 16 lysine residues were modified. This destabilization was due to electrostatic repulsions introduced by the entering citraconyl groups. 相似文献
45.
Nathaniel Diamant Erik Reinertsen Steven Song Aaron D. Aguirre Collin M. Stultz Puneet Batra 《PLoS computational biology》2022,18(2)
Supervised machine learning applications in health care are often limited due to a scarcity of labeled training data. To mitigate the effect of small sample size, we introduce a pre-training approach, Patient Contrastive Learning of Representations (PCLR), which creates latent representations of electrocardiograms (ECGs) from a large number of unlabeled examples using contrastive learning. The resulting representations are expressive, performant, and practical across a wide spectrum of clinical tasks. We develop PCLR using a large health care system with over 3.2 million 12-lead ECGs and demonstrate that training linear models on PCLR representations achieves a 51% performance increase, on average, over six training set sizes and four tasks (sex classification, age regression, and the detection of left ventricular hypertrophy and atrial fibrillation), relative to training neural network models from scratch. We also compared PCLR to three other ECG pre-training approaches (supervised pre-training, unsupervised pre-training with an autoencoder, and pre-training using a contrastive multi ECG-segment approach), and show significant performance benefits in three out of four tasks. We found an average performance benefit of 47% over the other models and an average of a 9% performance benefit compared to best model for each task. We release PCLR to enable others to extract ECG representations at https://github.com/broadinstitute/ml4h/tree/master/model_zoo/PCLR. 相似文献
46.
Lynn AM Jain CK Kosalai K Barman P Thakur N Batra H Bhattacharya A 《Journal of genetics》2001,80(1):9-16
Genomic sequence data are often available well before the annotated sequence is published. We present a method for analysis
of genomic DNA to identify coding sequences using the GeneScan algorithm and characterize these resultant sequences by BLAST.
The routines are used to develop a system for automated annotation of genome DNA sequences. 相似文献
47.
This paper emphasises the importance of vitality diagnostics in relation to healthy ageing and prevention of age-associated diseases. Ageing, reducing the reserve capacity, decreases the adaptability of various systems and increases the risk of functional disorders. The early recognition and treatment of functional disorders in vitality diagnostics laboratories provides an opportunity to prevent or delay the onset of degenerative diseases related to advanced age. 相似文献
48.
Sharma M Batra J Mabalirajan U Goswami S Ganguly D Lahkar B Bhatia NK Kumar A Ghosh B 《Immunogenetics》2004,56(7):544-547
CD14 is a lipopolysaccharide receptor known to be an important modulator of Th1–Th2 response during early childhood. Genetic association studies of the CD14 gene with asthma and atopic disorders have shown positive as well as negative results in different ethnic populations. The aim of this study was to test for association of C-159T functional promoter polymorphism with atopic asthma and serum IgE levels in northern and northwestern Indian populations. DNA was assayed for the CD14 C-159T polymorphism in a case-control study involving atopic asthmatics (n=187) and healthy normal controls (n=227), and in a family-based association study of 106 trios. The case-control study showed an association at the genotypic (P=0.0146) as well as the allelic level (P=0.0048). Moreover, we observed a deviation of allelic transmission from random proportions (P=0.024) in the transmission disequilibrium test analysis. When we analyzed our results for serum total IgE levels, against this polymorphism, we observed a difference at the genotypic (P=0.0026) as well as at the allelic level (P=0.0016) in a case-control study, whereas no association in the quantitative transmission disequilibrium test analysis was obtained. These findings provide suggestive evidence of association of the CD14 gene locus with atopic asthma in northern and northwestern Indian populations. 相似文献
49.
A convenient and biogenetic type synthesis of few naturally occurring chromeno dihydrochalcones and their in vitro antileishmanial activity 总被引:2,自引:0,他引:2
2',2'-Dimethyl chromeno dihydrochalcones are very rare in nature as plant secondary metabolites. Recently we have reported three such compounds from the plant Crotalaria ramosissima. Chromeno dihydrochalcones contain a 2',2'-dimethyl benzopyran system, which are frequently encountered in many natural products and exhibit a variety of biological activities. We here report the strategy to conveniently synthesize naturally occurring chromeno dihydrochalcones by biogenetic type pyridine or Amberlyst-15 catalyzed chromenylation of dihydrochalcones and in vitro antileishmanial activity of chromeno dihydrochalcones and their intermediates. 相似文献
50.
Howell GJ Herbert SP Smith JM Mittar S Ewan LC Mohammed M Hunter AR Simpson N Turner AJ Zachary I Walker JH Ponnambalam S 《Molecular membrane biology》2004,21(6):413-421
Secretory granules called Weibel-Palade bodies (WPBs) containing Von Willebrand factor (VWF) are characteristic of the mammalian endothelium. We hypothesized that vascular-specific antigens such as VWF are linked to endothelial identity and proliferation in vitro. To test this idea, the cellular accumulation of VWF in WPBs was monitored as a function of cell proliferation, confluence and passage number in human umbilical vein endothelial cells (HUVECs). We found that as passage number increased the percentage of cells containing VWF in WPBs was reduced significantly, whilst the protein was still detected within the secretory pathway at all times. However, the endothelial-specific marker protein, PECAM-1, is present on all cells even when WPBs are absent, indicating partial maintenance of endothelial identity. Biochemical studies show that a significant pool of immature pro-VWF can be detected in sub-confluent HUVECs; however, a larger pool of mature, processed VWF is detected in confluent cells. Newly synthesized VWF must thus be differentially sorted and packaged along the secretory pathway in semi-confluent versus confluent endothelial cells. Our studies thus show that WPB formation is linked to the formation of a confluent endothelial monolayer. 相似文献