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681.
This study examined how saddleback syndrome (SBS) and vertebral deformity affect the body shape and size of juvenile stage red spotted grouper, Epinephelus akaara, using the landmark‐based geometric morphometrics method. According to the criterion of skeletal conditions, three groups, i.e. vertebral deformity, SBS, and normal groups, were identified. The results revealed significant differences in body shape among the three groups, in which the vertebral‐deformed group had the deepest mid‐body, the broadest anterior part, and a shortened caudal peduncle, while the SBS group showed the shallowest mid‐body and the narrowest anterior part. The normal group had a body shape intermediate between the vertebral and SBS groups. A comparison of body size among the three groups revealed significant differences in centroid size, with the vertebral‐deformed and SBS groups showing smallest and largest centroid size, respectively. This study illuminates that not all skeletal deformities lead to smaller body size. We suggest that rearing conditions might have caused the deformities reported herein.  相似文献   
682.
Coexpression of desmosomal proteins and vimentin has been reported in a specific mesenchymal phenotype. This study investigated the expression of vimentin-binding desmosomal proteins in human dental pulp fibroblasts (DPF) and odontoblasts. The dental pulp has no cells expressing desmocollin (DSC) 1-3, desmoglein (DSG) 1-3, junction plakoglobin (JUP), or desmoplakin (DPK) 1 and 2 except for odontoblasts expressing DPK. A confocal image by laser-scanning microscopy demonstrated the diffuse distribution of DPK in the cytoplasm throughout the odontoblast processes. In culture, the mRNA expression of JUP and DPK1, but not DSC1-3 and DSG1-3, was detected in all DPF clones tested and also in odontoblast-like cells (OB) expressing osteocalcin and dentin sialophosphoprotein mRNAs established in the differentiation medium. The DPF having the potential to differentiate into OB expressed vimentin, but not DPK before culturing in the differentiation medium, whereas OB expressed vimentin-binding DPK1. These results suggest that DPF usually expresses DPK1 mRNA, and that the DPK1 production and the bonding of vimentin to DPK1 occur in DPF with the differentiation into odontoblasts.  相似文献   
683.
684.
N Nitta  S Yamamoto  Y Yamaoka  K Ozawa 《Life sciences》1988,42(20):1973-1979
The effects of hepatic inflow occlusion without venous shunt on the viability of the liver were investigated with respect to liver energy metabolism in dogs, subjected to portal triad cross-clamping (Pringle's maneuver) for 10, 30 and 60 min. The concentrations of ketone bodies and the arterial blood ketone body ratio (KBR) were decreased markedly by hepatic inflow occlusion, but recovered upon recirculation. The initial velocity of KBR recovery was 0.150/min after 10-min clamping, 0.140/min after 30-min clamping and 0.032/min after 60-min clamping. KBR recovery was delayed when hepatic inflow occlusion exceeded 30 min, which indicates that hepatic inflow occlusion for 60 min causes severe inhibition of energy generation in liver mitochondria. These findings indicate that the safety period for hepatic inflow occlusion without venous shunt is between 30 and 60 min in dogs, and that mortality can be predicted by measuring the initial velocity of KBR recovery upon recirculation.  相似文献   
685.
686.
The electric field dependence (up to 21 kV/cm) of the steady-state and decay signals has been examined on the four well-fractionated samples of poly(γ-benzyl-L -glutamate), [Glu(OBzl)]n, in N,N-dimethylformamide at 535 nm and 20°C. Together with the data previously obtained from the reversing-pulse electric birefringence [Ueda, K., Nomura, M. & Yamaoka, K. (1983) Biopolymers 22 , 2077–2090], the steady-state birefringence and field-free relaxation time were analyzed by a method that takes into account the polydispersity of the chain length. The weight-average chain length, (lw), permanent dipole moment, (μw), electric polarizability anisotropy, (Δαw), and the length-independent optical anisotropy factor were evaluated. The axial translation per residue was calculated for the [Glu(OBzl)]n helix, but the uncertainly involved in the weight-average molecular weights, determined from light scattering by different investigators, makes the determination of the exact conformation of [Glu(OBzl)]n difficult. The contribution of Δαw to electric field orientation was found to be significant, since Δαw was approximately proportional to lw. A linear relationship also exists between μw and lw, when the [Glu(OBzl)]n helix is shorter than about 1200 Å.  相似文献   
687.
A rapid method to determine the allelic variants of the sheep PrP gene was developed. DNA samples from 128 Suffolk sheep (39 rams and 89 ewes) were screened by using polymerase chain reactions and dot-blot hybridization with 32P-labeled nine allele-specific oligonucleotide probes corresponding to the polymorphic PrP codons 112, 136, 154 and 171. Three allelic variants of the PrP gene, PrPMARQ, PrPTARQ and PrPMARR, were found in the flocks. Among those variants, nearly half of the ewes had alleles of the 171-Arg variant that is closely associated with resistance to natural scrapie. Assessments of allelic mutations of the PrP gene may help to select the scrapie-resistant progenitors in the flocks.  相似文献   
688.
Prolylendopeptidase activity was increasingly depressed with time from 6 to 24 hr after the start of sensitization in the delayed hypersensitive guinea pig skin lesion induced by bovine gamma-globulin as an antigen. The remarkably depressed activity of the enzyme in the violently inflamed skin began to be restored slowly 48 hr after sensitization, and its activity was ultimately recovered to the original level by 504 hr after a single sensitization in vivo. Depression of the enzymatic activity is caused by a novel prolyendopeptidase inhibitor, whose amino acid composition is 7 Glu, 1 Ser, 2 Gly, 1 Ala, 2 Pro, and 1 Val, generated by inflammation.  相似文献   
689.
The influence of pelagic larval duration (PLD) and egg type dispersal capabilities of 35 demersal and pelagic-spawning tropical fish species is examined in relation to their abundance on the temperate coasts of Japan. The PLDs of pelagic spawners were significantly longer than those of demersal spawners, and a high occurrence of pelagic spawners on the temperate coasts suggests that these fishes are more easily transported to temperate coasts than demersal spawners. For demersal spawners, the common species on the temperate coasts had significantly longer PLDs than the rare species; this suggests that PLD is a major factor influencing the distribution patterns of tropical demersal spawners on temperate coasts. Moreover, a negative correlation between PLD and the abundance of some species of pelagic and demersal spawners suggests the presence of reproductively active fishes in northern subtropical and even in temperate waters.  相似文献   
690.
MeOH and water extracts were obtained from 16 species of infected leaves with rust fungi belonging to 18 species in 6 families: Pucciniaceae, Melampsoraceae, Coleosporiaceae, Pileolariaceae, Phragmidiaceae, and Phakopsoraceae. All the extracts of rust-infected plants with telia showed the teliospore-inducing activity for wheat leaf rust (Puccinia recondita f. sp. tritici).  相似文献   
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