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21.
Sources of residual setup error after image guidance include image localization accuracy, errors associated with image registration, and inability of some treatment couches to correct submillimeter translational errors and/or pitch and roll errors. The purpose of this experimental study was to measure setup error after image‐guided correction of the canine intracranial region, using a four degrees‐of‐freedom couch capable of 1 mm translational moves. Six cadaver dogs were positioned 45 times as for clinical treatment using a vacuum deformable body cushion, a customizable head cushion, a thermoplastic mask and an indexed maxillary plate with a dental mould. The location of five fiducial markers in the skull bones was compared between the reference position and after megavoltage (MV), kilovoltage (kV) and cone‐beam computed tomography (CBCT)‐guided correction using orthogonal kV images. The mean three‐dimensional distance vectors (3DDV) after MV, kV and CBCT‐guided correction were 1.7, 1.5 and 2.2 mm, respectively. All values were significantly different (P < .01). The 95th percentiles of the 3DDV after online MV, kV and CBCT‐guided correction were 2.8, 2.6 and 3.6 mm, respectively. Residual setup error in the clinical scenario examined was on the order of millimetres and should be considered when choosing PTV margins for image‐guided radiation therapy of the canine intracranial region.  相似文献   
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The 2011 earthquake severely damaged the Fukushima Daiichi Nuclear Power Plant (FNPP), resulting in the release of large quantities of radioactive material into the environment. The deposition of these radionuclides in rice straw as livestock feed led to the circulation of contaminated beef in the market. Based on the safety concern of the consumers, a reliable method for estimating concentrations of radioactive cesium in muscle tissue is needed. In this study, we analyzed the concentrations of radioactive cesium in the blood and skeletal muscle of 88 cattle, and detected a linear correlation between them. We then developed software that can be used to estimate radioactive cesium concentrations in muscle tissue from blood samples. Distribution of this software to the livestock production field would allow us to easily identify high‐risk cattle, which would be beyond the safety regulation, before shipping out to the market. This software is planned to be released as freeware. This software would contribute to food safety, and aid the recovery of the livestock industry from the damage creacted by the 2011 Tohoku earthquake and tsunami.  相似文献   
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Numerous human diseases are associated with the chronic expression of misfolded and aggregation-prone proteins. The expansion of polyglutamine residues in unrelated proteins is associated with the early onset of neurodegenerative disease. To understand how the presence of misfolded proteins leads to cellular dysfunction, we employed Caenorhabditis elegans polyglutamine aggregation models. Here, we find that polyglutamine expansions disrupted the global balance of protein folding quality control, resulting in the loss of function of diverse metastable proteins with destabilizing temperature-sensitive mutations. In turn, these proteins, although innocuous under normal physiological conditions, enhanced the aggregation of polyglutamine proteins. Thus, weak folding mutations throughout the genome can function as modifiers of polyglutamine phenotypes and toxicity.  相似文献   
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Complete sequences of mitochondrial (mt) genomes of eight Japanese Black cattle were determined to investigate the relationships between mt deoxyribonucleic acid (DNA) displacement loop (D-loop) types and other mtDNA regions and to identify the variation in the coding region that may influence the economic traits. The survey of mitochondrial sequences in the encoding region revealed 14 substitutions including six antonymous substitutions and one in 16S ribosomal ribonucleic acid (rRNA). Three methods of polymorphic DNA analyses (polymerase chain reaction [PCR]-restriction fragment length polymorphism [RFLP], mismatch PCR-RFLP, PCR-single-strand conformation polymorphism [SSCP]) were performed on these seven candidate substitutions (base pair [bp] 2,232, 12,158, 12,908, 13,310, 14,122, 14,140, and 14,565) for 202 Japanese Black cattle. The substitution of bp 13,310 was observed in all samples, but not in the reference sequence, indicating that this is a minor substitution or a sequencing mistake in the reference sequence. The substitutions at bp 14,122, 14,140, and 14,565 were observed in only a few samples, suggesting that these were also minor substitutions. The substitutions at bp 2,232 (16S rRNA), 12,158, and 12,908 (reduced nicotinamide adenine dinucleotide-ubiquinone oxidoreductase chain-5) were closely related to mitochondrial D-loop types that have previously been related to differences in the carcass traits of Japanese Black cattle. Evaluation of the effects on six carcass traits with mixed model procedures suggests that the bp 2,232 substitution affects longissimus muscle area and beef marbling score. The substitution at bp 2,232 is a strong candidate for the mitochondrial effect on meat quality.  相似文献   
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To detect the anti-P53 antibodies of dogs with tumors, a GST-recombinant canine (rc) P53 fusion protein was expressed and purified. Immunoblot analysis was performed using this GST-rcP53 fusion protein as an antigen and serum samples from dogs suffering from tumors as primary antibodies. Out of 16 serum samples obtained from various tumor cases, four samples showed reaction with GST-rcP53. In contrast, serum from other 12 dogs with tumors, four dogs with non-neoplastic diseases and two control healthy dogs (as controls) did not show any reaction with GST-rcP53 in immunoblotting. The p53 gene mutation and the P53 protein expression were examined, using the tumor tissues to explore the relationship between the existence of the GST-rcP53 bands, gene mutations of p53 and the accumulation of P53 protein. One case, which showed a clear GST-rcP53 band, had a point mutation of the p53 cDNA and showed nuclear accumulation of P53 protein. These results suggest that the anti-P53 antibodies are also produced in tumor dogs with p53 gene mutations.  相似文献   
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SMEDI and hog cholera viruses were shown to have marked effects upon the survival of the embryo (from conception to 30 days of gestation), the fetus (from 30 days of gestation until birth), and the neonatal pig (from birth until five days after birth). Embryonic infection was characterized by death and absorption of the embryo and in some instances the return to estrus after an irregular estrous cycle. Embryonic infection also may have been responsible for the development of some abnormal pigs. Fetal infection caused death with mummification of one or more fetuses and occasionally all fetuses in the uterus. Infection established in early gestation produced effects on the fetus which apparently persisted until after birth and varied from a persistent viremia (as in hog cholera infection) to an undefined lack of resistance in the newborn (as in SMEDI virus infection). Hog cholera vaccinal virus was the more virulent of the two virus types and reacted somewhat like rubella virus, in that infection apparently could be established in the fetus even in middle trimester of pregnancy, and possibly later. SMEDI viruses, in contrast, were less virulent and were most pathogenic when the dam was infected during the first 30 days of pregnancy. Immunity against either virus could be established in the nonpregnant gilt and was most effective in preventing intrauterine infections with that virus. However, with as many as 10 enteroviruses (five are known to cause intrauterine infection) it was believed that maintaining a closed breeding herd and introducing new stock into contact with the breeding herd at least 30 days before breeding time might be a safer means of control.  相似文献   
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Expression of a tumor-associated antigen, RCAS1, in canine mammary tumors   总被引:2,自引:0,他引:2  
Receptor-binding cancer antigen expressed on SiSo cells (RCAS1), one of novel cancer cell-surface antigens, is strongly expressed in invasive cancers. RCAS1 inhibits the in vitro growth of lymphocytes such as T cells and natural killer (NK) cells, and induces apoptotic cell death. We investigated the expression of RCAS1 in canine mammary tumor cell lines and tumor cells by immunohistochemistry, and also in situ deoxyribonucleic acid (DNA) fragmentation in tumor-infiltrating lymphocytes (TILs) by the terminal deoxynucleotidyl transferase mediated deoxyuridine triphosphate nick end labeling (TUNEL) method. All canine mammary tumor cell lines expressed RCAS1 at both the messenger ribonucleic acid (mRNA) and protein level. Immunohistochemically, RCAS1 was negative in 100% of normal mammary glands, but was expressed in 100% of malignant tumors examined. In most malignant mammary tumors, RCAS1 was localized in the cytoplasm with no polarity of expression. In benign mammary tumors, it was detected on the luminal surface of the tumor cell. RCAS1 expression or localization was significantly correlated with malignancy. In situ DNA fragmentation of CD3-positive TILs was observed in RCAS1-expressing tumors. RCAS1-expressing tumors, indicating a possible induction of apoptotic cell death in TILs through RCAS1 expression. These observations suggest that RCAS1 probably plays an important role in tumor progression and escape from immune surveillance in canine mammary tumors.  相似文献   
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