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排序方式: 共有409条查询结果,搜索用时 15 毫秒
381.
A fibrolytic consortium, dominated by the rumen cellulolytic bacterium Fibrobacter succinogenes, was artificially constructed on hay stems to detect and identify rumen bacteria that can potentially interact with F. succinogenes . Consortium-bacterial members were determined by DGGE and sequencing analysis targeted bacterial 16S rDNA. An artificial consortium was formed in a 2-step incubation of hay stems; the first step with group 1, 2 or 3 F. succinogenes strains, the second step with rumen fluid. After consortium formation, morphologically different bacteria were observed in association with F. succinogenes . DGGE exhibited more than 30 bands, the pattern of which depended on the F. succinogenes group. Sequencing suggested that Butyrivibrio fibrisolvens, Pseudobutyrivibrio ruminis , Clostridium sp., F. succinogenes group 2, Prevotella ruminicola and unclassified Bacteroides were prominent in the group 1 consortium and that Treponema bryantii , B. fibrisolvens , Acinetobacter sp, and Wolinella succinogenes were prominent in the group 2 consortium. However, in the group 3 consortium, F. succinogenes -like bacteria were microscopically undetectable, whereas cellulolytic Ruminococcus albus and F. succinogenes group 1 were prominent, suggesting that the group 3 cannot be a core member of this consortium. This study is the first attempt to identify bacterial members of a fibrolytic consortium dominated by a specific bacterium. 相似文献
382.
Tania Yonow Darren J. Kriticos Noboru Ota Johnnie Van Den Berg William D. Hutchison 《Journal of pest science》2017,90(2):459-477
Chilo partellus is a major crop pest in Asia and Africa, and has recently spread to the Mediterranean region. Knowledge of its potential distribution can inform biosecurity policies aimed at limiting its further spread and efforts to reduce its impact in areas that are already invaded. Three models of the potential distribution of this insect have been published, each with significant shortcomings. We re-parameterized an existing CLIMEX model to address some parameter inconsistencies and to improve the fit to the known distribution of C. partellus. The resulting model fits the known distribution better than previous models, highlights additional risks in equatorial regions and reduces modelled risks in wet and extremely dry regions. We bring new insights into the role of irrigation in the potential spread of this invasive insect and compare its potential distribution with the present known distribution of its hosts. We also distinguish regions that are suitable for supporting persistent populations from those that may be at risk from ephemeral populations during favourable seasons. We present one of the first demonstrations of a new capability in CLIMEX to automatically estimate parameter sensitivity and model uncertainty. Our CLIMEX model highlights the substantial invasion risk posed by C. partellus to cropping regions in the Americas, Australia, China, Europe, New Zealand and West Africa. Its broad host range and reported impacts suggest that it should be a pest of significant concern to biosecurity agencies in these presently uninvaded regions. 相似文献
383.
Teruyoshi Tanaka Kenji Takahashi Naoki Iwamoto Yasuo Agawa Yoshifumi Sawada Yukihiro Yoshimura Nobuhiro Zaima Tatsuya Moriyama Yukio Kawamura 《Fisheries Science》2012,78(4):911-921
We have shown that dietary bluefin tuna skin (TUS) protects against carbon tetrachloride (CCl4)-induced hepatic damage in mice. The CCl4-induced necrotic area was decreased in mice fed a TUS-containing diet. Consistent with the decreased necrotic area, dietary TUS markedly lowered the elevated serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities and the thiobarbituric acid-reactive substance (TBARS) formation induced by CCl4 injection. TUS diets also decreased phosphorylation of inhibitory kappa B-?? and blocked the translocation of nuclear factor-kappa B to the nucleus. TUS is composed mainly (80.7?%) of type I collagen, and our results revealed that dietary tuna collagen peptides (TUCP) attenuated the increased hepatic necrotic area, serum AST and ALT activities, and liver TBARS levels induced by CCl4, similar to TUS, thus enabling us to attribute the hepatoprotective action of TUS in CCl4-intoxicated mice to tuna collagen. Therefore, TUS and TUCP may be potential food resources that are capable of alleviating hepatitis symptoms. 相似文献
384.
Shiga A Ota Y Ueda Y Hosoi M Miyajima R Hasegawa K Mizuhashi F 《Journal of toxicologic pathology》2010,23(4):253-260
Focal granulomatous inflammation developed in the livers of five 10-week-old male Sprague-Dawley rats. The characteristic features of this lesion were the presence of foreign body multinucleated giant cells engulfing calcium deposits and site-specific development in a fissure formed in a sub-lobation in the left lobe or interlobar fissure of the medial lobe of the liver. To clarify the pathogenesis of this lesion, rat livers showing abnormal sub-lobation or lobar atrophy, rat livers in an acute dermal toxicity study and guinea pig livers in a skin sensitization test were also examined histologically. Consequently, the present lesion was considered to be a reactive change against calcium that was dystrophically deposited in the area of hepatocellular necrosis due to delayed circulatory disturbance caused by external pressure or extension force. Granulomatous lesions like in the present cases should be differentiated from those caused by evident exogenous pathogens such as chemicals or microorganisms. 相似文献
385.
Yasuo Takijima Futoshi Katsumi Kyokuhei Takezawa 《Soil Science and Plant Nutrition》2013,59(3):173-182
Characteristics of heavy metal contamination in paddy soils were discussed with respect to the soil and field conditions influencing the metal contents in rice. 1. In contaminated areas along the Kuzuryu River, the heavy metal contents of rice (expressed as the average of each area) were largely related to contents of paddy soils in 0.1 N HCl soluble forms as well as in total contents. A correlation was also found for the ratio of Cd to Zn in their soluble forms in the soil. 2. Within a given contaminated field plot, the heavy metal contents were not uniform, i.e: they were high around the irrigation inlet and decreased towards the outlet. However, these changes seemed to alter the Cd rice level much less than expected. 3. Soil pH and exchangeable Ca were negatively correlated with the Cd content of rice at a highly significant level. An un-drained field condition with a low soil Eh remarkably lowered the Cd content, particularly during rainy weather after the heading of the plant. 4. Based on a comparison of the extractable heavy metal contents in the waste ores and their contaminated soils, sulfide minerals derived from the mining appeared to be weathered more rapidly in the soil. With some extraction methods, the Cd origin was distinguished as the solubility of the metal in the soil among the waste products from the zinc mining and refinery. 相似文献
386.
387.
388.
Kitahara G Nambo Y El-Sheikh Ali H Kajisa M Tani M Nibe K Kamimura S 《The Journal of reproduction and development》2012,58(1):98-104
This study was carried out to evaluate the blood profile and tissue expression of Anti-Müllerian hormone (AMH) as a biomarker for granulosa-theca cell tumors (GTCTs) in cattle. Five cases with unilateral ovarian GTCTs (GTCT group) were investigated in comparison to other groups of Japanese Black cows, which had either cystic ovarian disease (COD group, n=5), a functional corpus luteum on Days 9 to 11 of the estrous cycle (Day 0=estrus; CL group, n=13) or received superovulation treatment (SOT group, n=13). We used transrectal ultrasonography and measured plasma AMH, estradiol-17β (E(2)), progesterone (P(4)) and testosterone (T) levels. Moreover, GTCT tissues were collected and examined by immunohistochemical staining (IHC) for AMH. In the GTCT group, ultrasound images of GTCTs were variable and not definitive. However, the AMH level in the GTCT group (n=3, 58.1 ± 66.3 ng/ml) was significantly higher than in the COD, CL and SOT groups (0.1 ± 0.1 ng/ml for GTCT vs. COD, P<0.05; 0.2 ± 0.1 and 0.3 ± 0.2 ng/ml, respectively for GTCT vs. CL and SOT, P<0.01). The other hormonal levels in the GTCT group had no significant differences compared with the COD or SOT group. Neoplastic granulosa cells labeled with AMH antibody clearly demonstrated a variety of tissue patterns in all cases by IHC. To the best of our knowledge, this is the first study to investigate the blood profile and IHC of AMH in bovine GTCTs. Our findings indicate that AMH may be a novel biomarker to diagnose GTCTs in cattle. 相似文献
389.
Konosuke OTOMARU Takuro FUJIKAWA Yasuo SAITO Takaaki ANDO Takeshi OBI Naoki MIURA Chikara KUBOTA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(9):1191-1193
A 10-month-old Japanese black heifer was diagnosed as having an intra-abdominal
cyst using computed tomography (CT). Through a posterior ventral midline incision, the
cyst was removed, and the heifer completely recovered after the surgery. CT scans enabled
detection of the intra-abdominal cyst and measurements of the diameter of the cyst before
the surgery. 相似文献
390.