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91.
92.
Thymomas are one of the most common tumors of the cranial mediastinum in dogs; however there is limited information available on the use of radiation therapy for treating this neoplasm. Objectives of the current retrospective observational study were to describe outcomes and side effects of a hypofractionated radiation therapy protocol in a group of dogs with confirmed thymoma. A total of eight dogs were included. To generate individualized treatment plans, we designed the planning target volume according to the limits on mean lung dose and the percentage of the total lung volume exceeding 20 Gy (V20). The total administered dose was 48–49 Gy, with one fraction per week for a total of six to seven fractions. After therapy, two dogs achieved complete responses, two achieved partial responses, and the disease remained stable in two. Two dogs died during the radiation therapy protocol and were not classified. The median mean lung dose and V20 were 6.0 Gy (range: 3.1–15.0 Gy) and 12.4% (range: 2.3–27.5%), respectively. The overall response rate was 50.0%, and the median time to response following treatment initiation was 22 days (range: 14–115 days). Acute and late side effects were common in the skin and/or lung and were self‐limiting or asymptomatic. The median survival time was not reached (range: 8–1128 days) and the 1 year survival rate was 75.0%. Hypofractionated radiation therapy was well tolerated in this sample of dogs with thymoma and may be considered when owners decline surgical treatment or the tumor is deemed unresectable.  相似文献   
93.
The purpose of this study was to evaluate changes of very low-density lipoprotein (VLDL) components in hepatic blood (HB) from 5 nonlactating nonpregnant cows fasted from days 0 to 3 and subsequently refed to day 10 and, in addition, to assess those of other lipoproteins. Increased phospholipid concentrations in each lipoprotein after the start of fasting suggested their availability for the surface lipids of lipoproteins. Although the VLDL-triglyceride (TG) concentration in HB from all cows increased on day 1, the value on day 4 became similar to that on day 0. However, the concentration on day 10 was significantly increased. In all cows, the decreased ratio of the VLDL-TG concentration in HB to the non-esterified fatty acids (NEFA) concentration in portal blood (PB) on day 4 appeared to reflect relatively decreased secretion of TG as VLDL by NEFA excessively mobilized to the liver via PB. The markedly increased ratio on day 10 was considered to contribute to the improvement of hepatic lipidosis.  相似文献   
94.
This study investigated general physicochemical properties of tea garden soils at the alluvial plain of Cong River in Tan Cuong commune, Vietnam. Four gardens were selected as study sites on three transect lines established perpendicularly to the river. Soil samples were collected from the surface (0–10 cm) and subsurface (20–30 cm). Soil texture classes varied from sandy loam to light clay, which was affected by different terrains along the transect lines as well as severe disturbance such as terracing and earth excavation. The levels of total C and total N were correlated with increasing garden age, suggesting the replenishment of soil organic matter pool by the addition of plant residue and manure. Meanwhile, the soils showed strongly acidic nature with the average pH(H2O) of 3.7 at the surface and 3.9 at the subsurface. The effective cation exchange capacity (ECEC) was low at 4.7 and 4.9 cmolc kg?1, respectively, and dominated by exchangeable Al3+. Soil acidification was exacerbated with increasing garden age. However, a relatively large saturation of exchangeable calcium (Ca2+), potassium (K+), and magnesium (Mg2+) on the ECEC was found in the surface soils. The levels of available P were high, occasionally exceeding 1000 and 500 mg kg?1 at the surface and subsurface, respectively. In spite of strongly acidic condition, ammonium (NH4-N) applied as fertilizer was converted to nitrate (NO3-N) to move down to deeper layers. The levels of the bases, P, and mineral N seem to be principally determined by management practices. Significant portion of these nutrients was likely to exist in water soluble forms without adsorption onto soils. It should be required to develop proper schemes and to educate the owners for adequate fertilizer managements.  相似文献   
95.
To improve understanding of the mechanism of early ovarian development in eels, the effects of water temperature decrease on oocyte development, plasma levels of sex steroids [estradiol 17β (E2), testosterone (T), 11-ketotestosterone (11-KT)], and gonadotropin β-subunit [follicle-stimulating hormone (FSHβ), luteinizing hormone (LHβ)] messenger RNA (mRNA) expression levels were investigated. A total of 27 female Japanese eels Anguilla japonica were divided into initial, control, and test (water temperature decrease) groups. Starting on 22 September 2009, eels in the test group were reared in a tank with gradual temperature decrease from 25°C to 15°C over 39 days, while the control group was maintained at 25°C. The test group accumulated more oil droplets in their oocytes than did the other groups. Levels of sex steroids, especially 11-KT, were higher in the test group. In contrast, FSHβ and LHβ mRNA expression levels were lower in the test group. These results suggest that water temperature decrease only induced an early stage of ovarian development that was partly affected by an 11-KT increase. For further maturation, other environmental factors related to induction of gonadotropin increase appear to be needed.  相似文献   
96.
The optic tectum of Japanese quail embryos with in ovo exposure to methotrexate 100 ng/g egg on embryonic day 4 was examined from 3 to 24 hour after treatment. At 9 hour after methotrexate exposure, several apoptotic neuroepithelial cells appeared in the ventricular zone of the optic tectum; these increased in number and were diffusely distributed throughout all layers of the ventricular zone of the optic tectum at 12 hour. At 24 hour, neuroepithelial cells in the ventricular zone of the optic tectum were eliminated and showed sparse cell density. Throughout the experimental period, proliferation of neuroepithelial cells in the ventricular zone of the optic tectum of methotrexate-treated embryos was inhibited. These results suggest that neuroepithelial cells in the ventricular zone of the optic tectum in Japanese quail embryos can be affected by folic acid antimetabolites, methotrexate, at an early embryonic stage.  相似文献   
97.
98.
Various canine breeds are remarkably different from each other not only in their sizes and shapes but also in behavioral traits, suggesting that some of them are under genetic control. Although dopaminergic neurotransmission system is considered to affect animal behavior, little is known about related genes in canine. Relations between specific alleles in polymorphic regions of the dopamine receptor D4 gene (DRD4) and personality or psychiatric disorders have been reported in humans, and we first found polymorphism in exon III region of the gene in 4 canine breeds. In this study we surveyed allele frequency distribution in 23 breeds including a total of 1,535 unrelated individuals. In exon III, 8 alleles including a novel allele were identified. A group of breeds in which the alleles 447b, 498 and 549 were frequent tended toward high scores in aggression-related behavioral traits than that with frequent alleles 435 and 447a. Moreover, a polymorphism based on 24 bp insertion/deletion was found in exon I region for the first time in dogs. This information may be of use for candidate gene studies of behavioral variation in dogs.  相似文献   
99.
To test whether glycosphingolipids (GSLs) on the intestinal mucosa of rainbow trout (Oncorhynchus mykiss) serve as a binding receptor for Vibrio anguillarum, we analyzed neutral GSLs from rainbow trout intestinal mucosa and investigated the binding of bacteria to neutral GSLs. Two kinds of neutral GSLs, designated N-1 and N-2, were identified on high-performance thin-layer chromatography (TLC) plates. In TLC immunostaining tests, V. anguillarum bound only to galactosylceramide (GalCer), lactosylceramide and N-1 having the same TLC mobility as GalCer, but neither to glucosylceramide nor to N-2. These results suggest that N-1 is GalCer (Gal beta 1-1Cer) and also that N-1 (GalCer) on rainbow trout intestinal mucosa act as a receptor for V. anguillarum.  相似文献   
100.
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