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排序方式: 共有121条查询结果,搜索用时 156 毫秒
111.
Andy?Pang Andrew?D?Smith Paulo?AS?Nuin Elisabeth?RM?TillierEmail author 《BMC bioinformatics》2005,6(1):236
Background
General protein evolution models help determine the baseline expectations for the evolution of sequences, and they have been extensively useful in sequence analysis and for the computer simulation of artificial sequence data sets. 相似文献112.
Wuelton M Monteiro Fernando FA Val André M Siqueira Gabriel P Franca Vanderson S Sampaio Gisely C Melo Anne CG Almeida Marcelo AM Brito Henry M Peixoto Douglas Fuller Quique Bassat Gustavo AS Romero Oliveira Maria Regina F Lacerda Marcus Vinícius G 《Memórias do Instituto Oswaldo Cruz》2014,109(5):553-568
113.
M Verma R Metgud AS Madhusudan N Verma M Saxena A Soni 《Biotechnic & histochemistry》2014,89(7):529-534
Diabetes has been reported to affect salivary glands adversely in humans and experimental models. Glutamate oxaloacetate transaminase (GOT), glutamate pyruvate transaminase (GPT) and lactate dehydrogenase (LDH) are salivary enzymes that also are widely distributed in animal tissues. We determined GOT and GPT levels in saliva samples of 100 type 1 and 30 type 2 diabetic patients using reflectance spectrophotometry and compared them to 30 age and sex matched healthy controls. Statistically significant differences were observed in the mean values of GOT and GPT in type 1 diabetics compared to type 2 and control groups. Significantly higher GOT levels were found in the 1–20 year age group of type 1 diabetics. Our findings suggest that salivary gland damage is due to the same immunological attack that affects pancreatic β cells and results in type 1 diabetes. 相似文献
114.
Nestboxes are known to increase clutch size, enhance breeding success and affect the social mating system of several cavity nesters. Although in recent years various cavity nesters have been studied in nestboxes in South America, the effects of boxes on the biology of the study species are unknown. We evaluated the effects of nestboxes on the breeding biology and social mating system of Southern House Wrens Troglodytes aedon bonariae by comparing birds breeding in nestboxes and tree cavities in two cattle ranches in Buenos Aires Province, Argentina. Southern House Wrens nesting in boxes had higher breeding success but, contrary to studies on the temperate zone, we did not find differences in clutch size between Wrens breeding in nestboxes and tree cavities. The main causes of nest failure in tree cavities were nest predation and flooding of the cavity (70 and 23% of the failures, respectively) while in nestboxes predation and desertion were the most important causes of failure (38 and 34% of the failures, respectively). The social mating system of Southern House Wrens is monogamy with biparental care, and neither was affected by the boxes. Males did not attract secondary females to additional nestboxes; however, nestboxes are safer breeding sites than tree cavities, and females seemed to prefer males with nestboxes on their territory. These results suggest that nest quality alone might be not enough for secondary females to accept polygyny. 相似文献
115.
Richard J Dobson Patricia B Munroe Mark J Caulfield Mansoor AS Saqi 《BMC bioinformatics》2006,7(1):217-9
Background
There has been an explosion in the number of single nucleotide polymorphisms (SNPs) within public databases. In this study we focused on non-synonymous protein coding single nucleotide polymorphisms (nsSNPs), some associated with disease and others which are thought to be neutral. We describe the distribution of both types of nsSNPs using structural and sequence based features and assess the relative value of these attributes as predictors of function using machine learning methods. We also address the common problem of balance within machine learning methods and show the effect of imbalance on nsSNP function prediction. We show that nsSNP function prediction can be significantly improved by 100% undersampling of the majority class. The learnt rules were then applied to make predictions of function on all nsSNPs within Ensembl. 相似文献116.
Marcos VH Rambo Humberto R Gamba Gustavo B Borba Joaquim M Maia Carlos AS Ramos 《Biomedical engineering online》2010,9(1):46
Background
The results of an in vivo study on the "ratio method" used in electronic foramen locators (EFL) are presented. EFLs are becoming widely used in the determination of the working length (WL) during the root canal treatment. The WL is the distance from a coronal reference point to the point at which canal preparation and filling should terminate. The "ratio method" was assessed by many clinicians with the aim of determining its ability to locate the apical foramen (AF). Nevertheless, in vivo studies to assess the method itself and to explain why the "ratio method" is able to locate the apical foramen and is unable to determine intermediate distances were not published so far. 相似文献117.
Cloning, expression, purification, and characterization of the acid alpha-mannosidase from Trypanosoma cruzi 总被引:1,自引:0,他引:1
Vandersall-Nairn AS; Merkle RK; O'Brien K; Oeltmann TN; Moremen KW 《Glycobiology》1998,8(12):1183-1194
The acid alpha-mannosidase of Trypanosoma cruzi is a broad-specificity
hydrolase involved in the catabolism of glycoconjugates, presumably in the
digestive vacuole. We have cloned the alpha-mannosidase gene from a T.cruzi
epimastigote genomic library. The alpha-mannosidase gene was determined to
be single copy by Southern analysis, and similar sequences were not
detected in genomic digests of either Trypanosoma brucei or Leishmania
donovani. The coding region was subcloned into the Pichia pastoris
expression vector pPICZ, and alpha-mannosidase activity was detected in the
medium of induced cultures. The recombinant alpha- mannosidase demonstrated
a pH optimum, inhibition by swainsonine, Km, and substrate specificity
consistent with the characteristics of the alpha-mannosidase previously
purified from T.cruzi epimastigotes. The recombinant enzyme was purified
103-fold from the culture medium of Pichia pastoris and had a native
molecular mass of 359 kDa by gel filtration. A combination of SDS-PAGE,
deglycosylation with endo H, and NH2-terminal sequencing indicates that the
enzyme is originally synthesized as a homodimeric polypeptide that is
subsequently cleaved to form a heterotetramer composed of 57 and 46 kDa
subunits. A polyclonal antibody raised to the recombinant enzyme was shown
to immunoprecipitate the alpha-mannosidase from T.cruzi cell extracts and
will be used in future immunolocalization studies.
相似文献
118.
119.
M Morgan Conn Joe Kappock Dale Drueckhammer Richard Cammack Dennis Hall Tony Cass Jon D Stewart Graham RL Cousins Jeremy KM Sanders Sabine Flitsch Philip AS Lowden Richard Newman 《Current opinion in chemical biology》1999,3(6):631
A selection of interesting papers that were published in the two months before our press date in major journals most likely to report significant results in chemical biology. 相似文献
120.