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81.
A novel canine tumor cell line designated as the CMS-C cell line was established from pleomorphic rhabdomyosarcoma (RMS) raised in the prostate gland of a 14-year-old intact male mixed-breed dog. CMS-C cells displayed the same immunohistochemical characteristics (positive for vimentin and desmin and negative for cytokeratin and smooth muscle actin) as the original tumor cells and express myoD1 and UCP3, known as striated muscle-specific molecules, as shown by RT-PCR assay. Therefore, the established CMS-C cell line appears to be of rhabdomyoblast cell origin. The CMS-C cell line established from pleomorphic RMS will be a useful tool for further studies about canine RMS.  相似文献   
82.
对绿熟期的番茄果实采用不同剂量(10、20、40、80 kJ.m-2)的UV-B进行照射后,在温度34℃、相对湿度95%的环境中避光贮藏34 d。结果表明,在4个处理中,以20、40 kJ.m-2剂量的UV-B照射处理贮藏效果最好,有效地保持了果实硬度,并延缓了果实的转色时间。此外,20、40 kJ.m-2的UV-B照射处理还可促进果实总酚及黄酮成分的积累,从而增强果实在贮藏过程中的抗氧化能力,但UV-B照射处理却降低了果实中抗坏血酸的含量。10 kJ.m-2的UV-B照射处理同样具有类似效果,但作用程度较小。较高的照射剂量80 kJ.m-2尽管促进了果实番茄红素的积累,但同时也给果实质地、颜色及抗氧化功能方面带来了不利影响。因此,用于保持番茄果实感官品质及抗氧化能力的最佳UV-B照射剂量为20 kJ.m-2或40 kJ.m-2。UV-B照射作为一种非化学手段可以有效保持番茄采后感官品质并提高其抗氧化能力。  相似文献   
83.
This study determined biometric and weight parameters and relevant indices of diploid and triploid tench. Altogether, 137 siblings of tench were studied. The effect of ploidy level appeared in significantly better growth of triploids (P<0.001) as to biometric [total length (TL), standard length (SL), body height (BH), body width (BW)] and weight [fish weight (FW), carcass weight (CW)] parameters of T3 of both sexes and of T3+ females. The effect of ploidy level also appeared as significantly higher dressing percentage (DP; P<0.001) of triploid T3 females compared with other groups, significantly higher gonad weight (GW) and gonadosomatic index (GSI; P<0.001) of diploid T3 females, as well as GSI and hepatosomatic index of diploid T3+ females. The effect of sex appeared in significantly higher (P<0.001) biometric (TL, SL, BH, BW) and weight (FW, CW) parameters of T3 females of both ploidy levels, as well as of triploid T3+ females. The effect of sex also appeared as significantly higher DP (P<0.001) of males in diploid T3 fish, as well as of males of both ploidy levels in T3+ fish and significantly higher GW and GSI (P<0.001) of females in diploid T3 fish, as well as of females of both ploidy levels in T3+ fish. This study shows evidence for faster somatic growth and bigger final weight of triploid populations of tench compared with diploids in both age categories T3 and T3+.  相似文献   
84.
Journal of Plant Diseases and Protection - The gypsy moth, Lymantria dispar, is one of the most important pests of deciduous trees in Europe, occurring in all environmental zones of Europe except...  相似文献   
85.

Background

Osteoporosis and its main health outcome, fragility fractures, are large and escalating health problems. Skeletal damage may be the critical result of low-level prolonged exposure to several xenobiotics in the general population, but the mechanisms of their adverse effects are not clearly understood. The current study was aimed to investigate the possible ability of simultaneous subchronic peroral administration of selenium (Se) and diazinon (DZN) to induce changes in bone of adult male rats.In our study, twenty 1-month-old male Wistar rats were randomly divided into two experimental groups. In the first group, young males were exposed to 5 mg Na2SeO3/L and 40 mg of DZN/L in drinking water, for 90 days. Ten 1-month-old males without Se and DZN intoxication served as a control group. At the end of the experiment, macroscopic and microscopic structures of the femurs were analysed using analytical scales, sliding instrument, and polarized light microscopy.

Results

The body weight, femoral length and cortical bone thickness were significantly decreased in rats simultaneously exposed to Se and DZN (P < 0.05). These rats also displayed different microstructure in the middle part of the compact bone where vascular canals expanded into central area of substantia compacta. The canals occurred only near endosteal surfaces in rats from the control group. Additionally, a smaller number of primary and secondary osteons, as well as a few resorption lacunae were observed near endosteal surfaces in rats simultaneously administered to Se and DZN. The resorption lacunae as typical structures of bone resorption manifestation are connected with an early stage of osteoporosis. Histomorphometric analysis revealed that area, perimeter, maximum and minimum diameters of primary osteons’ vascular canals were significantly increased (P < 0.05) in the Se-DZN-exposed rats. On the other hand, all measured variables of Haversian canals and secondary osteons were considerable reduced (P < 0.05) in these rats.

Conclusions

Simultaneous subchronic peroral exposure to Se and DZN induces changes in macroscopic and microscopic structures of the femurs in adult male rats, and also it can be considered as possible risk factor for osteoporosis. The current study contributes to the knowledge on damaging impact of several xenobiotics on the bone.  相似文献   
86.
87.
We used a Bayesian classification approach to predict the bovine viral-diarrhoea-virus infection status of a herd when the prevalence of persistently infected animals in such herds is very small (e.g. <1%). An example of the approach is presented using data on beef herds in Wyoming, USA. The approach uses past covariate information (serum-neutralization titres collected on animals in 16 herds) within a predictive model for classification of a future observable herd. Simulations to estimate misclassification probabilities for different misclassification costs and prevalences of infected herds can be used as a guide to the sample size needed for classification of a future herd.  相似文献   
88.
89.
The zoonotic characteristic of Mycobacterium avium subsp. avium (MAA) represents a veterinary and economic problem in infected pigs. In this study, we analysed cell-mediated immunity six months after experimental infection by measuring interferon-γ (IFN-γ) production and by performing lymphocyte transformation tests after in vitro re-stimulation with the MAA-derived antigen. At the same time, IFN-γ-producing cells were characterised by flow cytometry. In MAA-infected animals, the production of IFN-γ increased in response to the MAA antigen in the blood, spleen and mesenteric lymph nodes. Similarly, a positive antigen-driven response was detected by the proliferation assay. In contrast, IFN-γ production and proliferation was undetectable after stimulation with the MAA antigen in uninfected control animals. These results indicate that both methods can be used for the identification of individual MAA-infected pigs. Using flow cytometry, we found that double-positive CD4(+)CD8(+) lymphocytes were the major T lymphocyte subset producing IFN-γ after in vitro re-stimulation.  相似文献   
90.
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