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21.
This study was conducted to investigate the effects of probiotics administration on fatty acid metabolism in Japanese Black cattle as per changes in blood fatty acid concentrations and blood biochemical tests. Eighteen clinically healthy Japanese Black female fattening cattle bred on the same fattening farm were randomly classified into the probiotics administration group (n=9) or the control group (n=9). In the probiotics administration group, 50 g of probiotics were started per animal per day at the age of 18 months, and the administration period was 2 months from the start date of the study. Blood was collected twice before starting the probiotics administration and at 2 months after starting the probiotics administration. In the probiotics administration group, palmitic, linoleic, arachidonic and α-linolenic acid tended to be higher at the end of the administration compared with those before probiotics administration. Additionally, as a result of multiple comparison test, monounsaturated fatty acids at Post was significantly higher, and the ω6 / ω3 ratio was significantly lower than in the control group. Vitamin A, E and albumin were significantly higher at the end of the administration than in the control group. In this study that administering probiotics to Japanese Black cattle in the late middle stage of fattening period did not have a significant effect on fatty acid metabolism during feed digestion and absorption, but suggested that may alter some blood fatty acids concentrations.  相似文献   
22.
稻秆还田方式对麦田N2O排放的影响   总被引:4,自引:1,他引:3  
通过田间试验研究了3种稻秆还田方式(表面覆盖、均匀混施和原位焚烧)对麦田N2O排放的影响.结果表明,不同稻秆还田方式麦田N2O排放量为:表面覆盖>对照(不施稻秆)>均匀混施>原位焚烧.与对照相比,稻秆表面覆盖显著增加麦田N2O排放量,而均匀混施和原位焚烧显著减少N2O排放量.N2O排放通量与土壤温度无显著相关性,与土壤水分呈显著正相关.与对照相比,稻秆均匀混施使小麦产量显著增加,表面覆盖和原位焚烧对小麦产量无显著影响.  相似文献   
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In this report, we describe a case of neuroendocrine carcinoma of undetermined origin in a dog. Necropsy revealed scattered small neoplastic nodules in the bilateral lungs and a small nodule in the parapancreatic lymph node. Histopathologically, both pulmonary and lymph nodal nodules showed a similar histologic pattern, with neoplastic cells being arranged in diffusely proliferating sheet-like cellular nests separated by variable amounts of fibrous septa, sometimes forming rosettes and duct-like structures. Scattered small necrotic foci and invasion to fibrous septa were typically observed. Neoplastic cells showed round to oval-shaped nuclei with prominent nucleoli and abundant eosinophilic cytoplasm that were positive for Grimelius' silver impregnation staining and immunostaining with cytokeratin, synaptophysin, vasoactive intestinal peptide and chromogranin A, indicative of the development of a neuroendocrine carcinoma. However, judging from the distribution of tumors lacking the portion suggestive of the primary site in any organ examined, as well as no further indication of differentiation potential of neoplastic cells, this tumor has so far been diagnosed as neuroendocrine carcinoma of undetermined origin.  相似文献   
26.
Burial of wheat straw in ditches and incorporation of wheat straw are the two main ways of returning wheat straw prior to rice cultivation in China. To examine the effect of burying wheat straw in ditches on CH4 emissions from rice cultivation, a field experiment was conducted at Yixing, Jiangsu, China in 2004. CH4 flux was measured using a closed-chamber technique in three treatments (CK, no wheat straw application; WI, evenly incorporating 3.75 t ha−1 wheat straw into the 0.1 m topsoil; WD, burying 3.75 t ha−1 wheat straw in 0.14-m deep by 0.25-m wide ditches). Seasonal CH4 emissions ranged from 49.7 to 218.4 kg CH4 ha−1. The application of wheat straw in these two ways significantly increased CH4 emissions by 4.0-fold and 4.4-fold, respectively ( P  < 0.05). Although CH4 flux from the non-ditch area in the WD treatment was as low as that in the CK treatment, it was counter-balanced by extremely high CH4 flux from the ditch, which was approximately 6.0-fold as much as that from WI, leading to comparability between treatments WI and WD in total CH4 emissions ( P  > 0.05). No significant difference was observed between the three treatments in grain yield ( P  > 0.05). The results indicated that burial of wheat straw in ditches is not a way to reduce CH4 emission from rice cultivation.  相似文献   
27.
The Liliaceous perennial Tricyrtis hirta, sometimes called ‘Japanese toad lily’, has recently become popular as an ornamental for pot and garden uses. Highly embryogenic callus cultures of this plant predominately consisted of diploid cells but also contained tetraploid cells after 1 year of establishment. In the present study, plans regenerated from the 1-year-old embryogenic callus cultures were subjected to ploidy level analysis and morphological characterization following 3 years of cultivation. Among 37 plants examined, 28 kept the diploid level (2n = 2x = 26) but nine were tetraploid (2n = 4x = 52) as indicated by FCM analysis and chromosome observation. Although no morphological alterations were detected in 26 out of 28 diploid regenerants, the remaining two showed noticeable variations: both were severely dwarf and had crimped leaves and many malformed flowers. The tetraploid regenerants had several horticulturally attractive characteristics compared with the diploid controls, such as longer shoots, thicker stems, and larger flowers. Thus regeneration of tetraploid plants from 1-year-old embryogenic callus cultures offers a possibility to improve the horticultural value of T. hirta, although regeneration of trueness-to-type plants is essential for utilizing the cultures for micropropagation and genetic transformation.  相似文献   
28.
We examined the effect of zeatin on the formation of shoot buds from explants and callus tissues derived from stem segments of Actinidia polygama Miq. (matatabi or silver vine). Stem and petiole segments cultured on combined broad-leaved tree medium and woody plant medium (BW medium) supplemented with zeatin for 40 days formed many shoot buds. Callus tissues derived from the stem segments and subcultured on BW medium supplemented with 6-benzyladenine and 1-naphthaleneacetic acid formed shoot buds when the medium contained 13.7µM zeatin. BW medium containing low concentrations of sucrose strongly induced the formation of shoot buds from the callus.  相似文献   
29.
The aim of the present study was to investigate whether changes in body temperature are related to the ovarian cycle in elephants. Rectal, tongue or fecal temperature was measured for 2 Asian and 5 African elephants using an electric thermometer. Evaluation of ovarian cycles was based on the changes in serum or fecal progestin. The mean +/- SD values of the rectal, tongue, and fecal temperatures were 36.3 +/- 0.3 (2 Asian), 36.2 +/- 0.5 (1 African) and 36.5 +/- 0.3 C (4 African), respectively; the fecal temperature was the highest of the 3 temperatures (P<0.01). The longitudinal changes in body temperatures correlated with the ovarian cycle, with higher temperatures occurring during the luteal phase. The fecal temperatures of one acyclic African elephant did not change cyclically. These results suggest that measurement of body temperature can be used to easily evaluate the ovarian cyclicity of an individual animal, although it might not be able to determine the ovarian cycle length.  相似文献   
30.
When fungal germlings, after forming haustoria of Blumeria graminis f. sp. hordei (B. graminis), were removed from the surfaces of barley coleoptiles by cellulose acetate, followed by challenge inoculation with the non-pathogen Erysiphe pisi, they infected the nonhost barley coleoptile cells. This phenomenon was not observed on the coleoptile surface when the fungal germlings of B. graminis were removed before the formation of haustoria. Also, when the surface was inoculated with the pathogen of barley B. graminis as a challenger, after removing the fungal germlings of inducer post haustorial formation, the penetration efficiency of the fungi increased significantly compared with that of the control. Furthermore, when we extracted the crude-susceptibility inducing factor (suppressor) from coleoptiles before and after the formation of haustoria of B. graminis, suppressor activity against infection with E. pisi was observed only in the extract of barley coleoptiles that included haustoria of B. graminis about 18 h or later after inoculation. Surprisingly, however, the extract did not increase the penetration efficiency of B. graminis significantly. Thus, we hypothesize that the suppressor extracted from barley coleoptiles in which B. graminis had formed haustoria has no effect on increasing the penetration efficiency of the primary infection from the appressorium of B. graminis but has an effect on the infection with non-pathogen E. pisi.  相似文献   
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