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1.
T Shibata  T Abe 《Animal genetics》1996,27(3):195-197
Vitamin D binding protein ( GC ) and serum protease inhibitor ( PI ) have been added to genetic markers in the Japanese quail. Both loci were controlled by autosomal codominant alleles named GCA, GCB and PIA, PIB, PIC, respectively. Close linkage between the loci for serum albumin ( ALB ) and GC protein is reported. Two recombinants were observed in 145 informative offspring of 14 families. The recombination frequency between the loci was estimated as 0.014±0.006. Thus, GC was assigned to linkage group II in the Japanese quail. No signs of linkage were observed among the loci for the ALB-GC complex, PI. serum prealbumin 2 ( PA2 ), phosphoglucose isomerase ( PG1 ), 6-phosphogluconate dehydrogenase ( PGD ) and esterase-D ( ESD ).  相似文献   
2.
Computer-aided detection (CAD) technology has been developed and demonstrated its potential to assist radiologists in detecting pulmonary nodules especially at an early stage. In this paper, we present a novel scheme for automatic detection of pulmonary nodules in CT images based on a 3D tensor filtering algorithm and local image feature analysis. We first apply a series of preprocessing steps to segment the lung volume and generate the isotropic volumetric CT data. Next, a unique 3D tensor filtering approach and local image feature analysis are used to detect nodule candidates. A 3D level set segmentation method is used to correct and refine the boundaries of nodule candidates subsequently. Then, we extract the features of the detected candidates and select the optimal features by using a CFS (Correlation Feature Selection) subset evaluator attribute selection method. Finally, a random forest classifier is trained to classify the detected candidates. The performance of this CAD scheme is validated using two datasets namely, the LUNA16 (Lung Nodule Analysis 2016) database and the ANODE09 (Automatic Nodule Detection 2009) database. By applying a 10-fold cross-validation method, the CAD scheme yielded a sensitivity of 79.3% at an average of 4 false positive detections per scan (FP/Scan) for the former dataset, and a sensitivity of 84.62% and 2.8 FP/Scan for the latter dataset, respectively. Our detection results show that the use of 3D tensor filtering algorithm combined with local image feature analysis constitutes an effective approach to detect pulmonary nodules.  相似文献   
3.
The 231-residue capsid (CA) protein of human immunodeficiency virus type 1 (HIV-1) spontaneously self-assembles into tubes with a hexagonal lattice that is believed to mimic the surface lattice of conical capsid cores within intact virions. We report the results of solid-state nuclear magnetic resonance (NMR) measurements on HIV-1 CA tubes that provide new information regarding changes in molecular structure that accompany CA self-assembly, local dynamics within CA tubes, and possible mechanisms for the generation of lattice curvature. This information is contained in site-specific assignments of signals in two- and three-dimensional solid-state NMR spectra, conformation-dependent 15N and 13C NMR chemical shifts, detection of highly dynamic residues under solution NMR conditions, measurements of local variations in transverse spin relaxation rates of amide 1H nuclei, and quantitative measurements of site-specific 15N–15N dipole–dipole couplings. Our data show that most of the CA sequence is conformationally ordered and relatively rigid in tubular assemblies and that structures of the N-terminal domain (NTD) and the C-terminal domain (CTD) observed in solution are largely retained. However, specific segments, including the N-terminal β-hairpin, the cyclophilin A binding loop, the inter-domain linker, segments involved in intermolecular NTD–CTD interactions, and the C-terminal tail, have substantial static or dynamical disorder in tubular assemblies. Other segments, including the 310-helical segment in CTD, undergo clear conformational changes. Structural variations associated with curvature of the CA lattice appear to be localized in the inter-domain linker and intermolecular NTD–CTD interface, while structural variations within NTD hexamers, around local 3-fold symmetry axes, and in CTD–CTD dimerization interfaces are less significant.  相似文献   
4.
《Cytokine》2015,72(2):132-138
The purpose of this study was to determine if vitamin D status before supplementation influences the cytokine response after supplemental vitamin D. Forty-six reportedly healthy adults (mean(SD); age, 32(7) y; body mass index (BMI), 25.3(4.5) kg/m2; serum 25-hydroxyvitamin D (25(OH)D), 34.8(12.2) ng/mL) were randomly assigned (double blind) to one of three groups: (1) placebo (n = 15), or supplemental vitamin D (cholecalciferol) at (2) 4000 (n = 14) or (3) 8000 IU (n = 17). Supplements were taken daily for 35 days. Fasting blood samples were obtained before (Baseline, Bsl) and 35-days after (35-d) supplementation. Serum 25(OH)D, 1,25-dihydroxyvitamin D (1,25(OH)D), cytokines, and intact parathyroid hormone with calcium were measured in each blood sample. Supplemental vitamin D increased serum 25(OH)D (4000 IU, ≈29%; 8000 IU, ≈57%) and 1,25(OH)D (4000 IU, ≈12%; 8000 IU, ≈38%) without altering intact parathyroid hormone or calcium. The vitamin D metabolite increases in the supplemental vitamin D groups (n = 31) were dependent on initial levels as serum 25(OH)D (r = −0.63, p < 0.05) and 1,25(OH)D (r = −0.45, p < 0.05) at Bsl correlated with their increases after supplementation. Supplemental vitamin D increased interferon (IFN)-γ and interleukin (IL)-10 in subjects that were vitamin D insufficient (serum 25(OH)D < 29 ng/mL) compared to sufficient (serum 25(OH)D  30 ng/mL) at Bsl. We conclude that supplemental vitamin D increase a pro- and anti-inflammatory cytokine in those with initially low serum 25(OH)D.  相似文献   
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7.
Heterotrophic chrysomonads of the genus Paraphysomonas are ubiquitous phagotrophs with diverse silica scale morphology. Over 50 named species have been described by electron microscopy from uncultured environmental samples. Sequence data exist for very few, but the literature reveals misidentification or lumping of most previously sequenced. For critically integrating scale and sequence data, 59 clonal cultures were studied light microscopically, by sequencing 18S ribosomal DNA, and recording scale morphology by transmission electron microscopy. We found strong congruence between variations in scale morphology and rDNA sequences, and unexpectedly deep genetic diversity. We now restrict Paraphysomonas to species with nail-like spine scales, establishing 23 new species and eight subspecies (Paraphysomonadidae). Species having base-plates with dense margins form three distinct subclades; those with a simple margin only two. We move 29 former Paraphysomonas species with basket scales into a new genus, Clathromonas, and describe two new species. Clathromonas belongs to a very distinct rDNA clade (Clathromonadidae fam. n.), possibly distantly sister to Paraphysomonas. Molecular and morphological data are mutually reinforcing; both are needed for evaluating paraphysomonad diversity and confirm excessive past lumping. Former Paraphysomonas species with neither nail-like nor basket scales are here excluded from Paraphysomonas and will be assigned to new genera elsewhere.  相似文献   
8.
Three series of bitobic arylpiperazine-phenyl-hexahydropyrazinoquino- lines analogues were designed, synthesizedand evaluated as a novel class of selective ligands for the dopamine D3 receptor. Compounds 15a (Ki of 11.7 ± 1.8 and 373 nM at D3 and D2, respectively), 15c (Ki of 5.49 and 264 nM at D3 and D2, respectively), 15e (Ki of 14.9 and 325 nM at D3 and D2, respectively), 15i (Ki of 13.8 and 401 nM at D3 and D2, respectively) and 15l (Ki of 13.6 and 870 nM at D3 and D2, respectively) were found to demonstrate good binding affinity and selectivity, and especially compound 15c showeda similar binding affinity and selectivity compared with the contrast drug BP897.  相似文献   
9.
Vitamin D3 (cholecalciferol) is endogenously produced in the skin of primates when exposed to the appropriate wavelengths of ultraviolet light (UV-B). Common marmosets (Callithrix jacchus) maintained indoors require dietary provision of vitamin D3 due to lack of sunlight exposure. The minimum dietary vitamin D3 requirement and the maximum amount of vitamin D3 that can be metabolized by marmosets is unknown. Observations of metabolic bone disease and gastrointestinal malabsorption have led to wide variation in dietary vitamin D3 provision amongst research institutions, with resulting variation in circulating 25-hydroxyvitamin D3 (25(OH)D3), the accepted marker for vitamin D sufficiency/deficiency. Multiple studies have reported serum 25(OH)D3 in captive marmosets, but 25(OH)D3 is not the final product of vitamin D3 metabolism. In addition to serum 25(OH)D3, we measured the most physiologically active metabolite, 1,25-dihydroxyvitamin D3 (1,25(OH)2D3), and the less well understood metabolite, 24,25-dihydroxyvitamin D3 (24,25(OH)2D3) to characterize the marmoset's ability to metabolize dietary vitamin D3. We present vitamin D3 metabolite and related serum chemistry value colony reference ranges in marmosets provided diets with 26,367 (Colony A, N = 113) or 8,888 (Colony B, N = 52) international units (IU) of dietary vitamin D3 per kilogram of dry matter. Colony A marmosets had higher serum 25(OH)D3 (426 ng/ml [SD 200] vs. 215 ng/ml [SD 113]) and 24,25(OH)2D3 (53 ng/ml [SD 35] vs. 7 ng/ml [SD 5]). There was no difference in serum 1,25(OH)2D3 between the colonies. Serum 1,25(OH)2D3 increased and 25(OH)D3 decreased with age, but the effect was weak. Marmosets tightly regulate metabolism of dietary vitamin D3 into the active metabolite 1,25(OH)2D3; excess 25(OH)D3 is metabolized into 24,25(OH)2D3. This ability explains the tolerance of high levels of dietary vitamin D3 by marmosets, however, our data suggest that these high dietary levels are not required.  相似文献   
10.
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