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91.
This study aimed to improve the nutritional value and utilization of soybean meal (SBM) used as feed ingredient for shrimp by an approach of solid‐state fermentation with Bacillus subtilis E20. The protein content and B. subtilis E20 proliferation significantly increased, as the initial moisture increased from 30% to 50% during fermentation. Compared with SBM, the protein content of FSBM increased by 19% after fermentation, accompanied by an increase of 18.75% in the total hydrolyzed amino acids. The free amino acid profile and content in FSBM also obviously increased by 374.9% compared with SBM. The FSBM is a good substitute for fish meal (FM) in a diet with 37% protein and 7% lipid content. The maximal replacement levels of FM in shrimp diet with SBM and FSBM were 37.42% and 61.67%, respectively, based on the feed efficiency estimated by a broken‐line analysis. The B. subtilis E20‐FSBM can be a potential protein source used as a replacement for FM in shrimp diet.  相似文献   
92.
Microbial consortia that cooperatively exchange electrons play a key role in the anaerobic processing of organic matter. Interspecies hydrogen transfer is a well-documented strategy for electron exchange in dispersed laboratory cultures, but cooperative partners in natural environments often form multispecies aggregates. We found that laboratory evolution of a coculture of Geobacter metallireducens and Geobacter sulfurreducens metabolizing ethanol favored the formation of aggregates that were electrically conductive. Sequencing aggregate DNA revealed selection for a mutation that enhances the production of a c-type cytochrome involved in extracellular electron transfer and accelerates the formation of aggregates. Aggregate formation was also much faster in mutants that were deficient in interspecies hydrogen transfer, further suggesting direct interspecies electron transfer.  相似文献   
93.
A cougar (Felis concolor) was diagnosed with hepatic yersiniosis by bacterial culture and histopathology. The animal had a 2-week history of anorexia and jaundice before its death. Grossly, the liver exhibited caseo-necrotic foci. Histopathologically, there was necrotizing and suppurative hepatitis, with large numbers of intralesional gram-negative coccobacilli. Additional hepatic lesions included central vein thrombosis, lymphoplasmacytic portal hepatitis, and capsulitis. Yersinia pseudotuberculosis coccobacilli were isolated in pure culture from the hepatic lesions. Because the hepatic lesions in this animal resemble those of other zoonotic diseases, such as plague and tularemia, veterinarians and laboratory personnel who handle samples should take adequate safety precautions. This report is the first to describe the pathology associated with hepatic yersiniosis in a cougar.  相似文献   
94.
An adult Domestic Longhair cat developed a subcutaneous mass in its tail. Histologically, this mass consisted of ill-defined pyogranulomas centered around aggregates of gram-positive, acid-fast filamentous bacteria, consistent with Nocardia. Due to the lack of fresh samples, DNA was extracted from formalin-fixed paraffin-embedded tissue sections and subjected to polymerase chain reaction amplification and DNA sequencing of 16S ribosomal RNA gene encompassing Nocardia sp.-specific sequences. Sequences analyzed using the GenBank database revealed 99.5% homology with Nocardia spp. and had the highest sequence homology of 98.2% with Nocardia tenerifensis among Nocardia spp. To the authors' knowledge, this is the first report of detection of N. tenerifensis genome associated with cutaneous nocardiosis in an animal.  相似文献   
95.
  1. The paucity of baseline data on coastal cetaceans due to a lack of research in developing countries frequently precludes assessment of their status and informed management actions for conservation.
  2. This study provides the first abundance estimates of Indo-Pacific humpback dolphins, Irrawaddy dolphins, and Indo-Pacific finless porpoises in the coastal waters of Matang, Peninsular Malaysia.
  3. Boat-based surveys covering 1,152 km2 of coastal waters with 4,108 km of survey effort were conducted between 2013 and 2016 to collect data for line transect analysis of Irrawaddy dolphins and finless porpoises. Photo-identification data of humpback dolphins were concurrently collected for mark–recapture analysis.
  4. Estimates of abundance from four sampling strata totalled 763 Irrawaddy dolphins (CV = 13%, 95% confidence interval (CI) [588, 990]) and 600 Indo-Pacific finless porpoises (CV = 27%, 95% CI [354, 1,016]).
  5. The annual abundance estimates of humpback dolphins ranged between 171 (95% CI [148, 208]) in 2014–2015 and 81 (95% CI [67, 98]) in 2015–2016, likely due to the presence of offshore individuals that moved in and out of the study area. The estuarine strata were inhabited by 68 (95% CI [63, 73]) inshore humpback dolphins in 2013–2014 to 87 (95% CI [78, 97]) dolphins in 2014–2015.
  6. As an International Union for Conservation of Nature important marine mammal area, the productive coastal waters of Matang are shown to support a high density of small coastal cetaceans, and the results serve as an important baseline for future studies to identify population trends for conservation management plans.
  相似文献   
96.
Canine mammary tumours (CMTs) are the most prevalent neoplasms in female dogs. Despite the high incidence of such tumours, a lack of easily accessible biomarkers still impedes early diagnosis of malignant CMTs. Herein we identify thymidylate synthetase (TYMS), hyaluronan and proteoglycan link protein 1 (HAPLN1) and insulin‐like growth factor‐binding protein 5 (IGFBP5) as CMT antigens eliciting corresponding autoantibodies in CMT cases. We establish enzyme‐linked immunosorbent assays (ELISAs) to detect autoantibodies to TYMS (TYMS‐AAb), HAPLN1 (HAPLN1‐AAb) and IGFBP5 (IGFBP5‐AAb) in sera from 81 dogs with malignant CMTs (41 in Stage I), 24 with benign CMTs and 35 healthy controls. Levels of all the three autoantibodies are elevated in the malignant group compared with the healthy or the benign group; notably, the elevated autoantibody levels significantly correlate with the stage‐I CMTs. For discriminating malignant CMTs from healthy control, the area under curve (AUC) of TYMS‐AAb is 0.694 with specificity of 82.9% and sensitivity of 50.6%. The AUC of utilising HAPLN1‐AAb for distinguishing the stage‐I CMTs from healthy controls is 0.711 with specificity of 77.1% and sensitivity of 58.5%. In differentiating malignant CMTs from the benign, the AUC of IGFBP5‐AAb reaches 0.696 with specificity of 70.8% and sensitivity of 67.9%, and a combination of IGFBP5‐AAb and TYMS‐AAb increases the AUC to 0.72. Finally, the AUC of combined HAPLN1‐AAb and IGFBP5‐AAb in discriminating the stage‐I CMTs from the benign achieves 0.731. Collectively, this study highlights a significant association of the three serum autoantibodies with early stage malignant CMTs.  相似文献   
97.
Monascus purpureus and its fermentation products have been used in food coloring and meat preservation in Asia for centuries and have also been recently used as dietary supplements because of their cholesterol-lowering ability. However, the presence of the mycotoxin citrinin (CTN), a secondary metabolite of Monascus species, in fermentation products is a potential threat to public health. In the present study, HPLC was used to analyze CTN levels in lipid and aqueous extracts of commercialized Monascus products. CTN was detected in lipid extracts of all examined samples at concentrations varying between 0.28 and 6.29 microg/g, but was not found in aqueous extracts. When human embryonic kidney cells (HEK293) were incubated for 72 h with Monascus extracts, the concentrations causing 50% cell death by all lipid extracts were in the range of 1.8-4.7 mg/mL, whereas aqueous extracts showed a lower cytotoxicity. Incubation of HEK293 cells with 60 microM pure CTN for 72 h caused cell viability to fall to 50% of control levels. In addition, coadministration of pure CTN and lipid extracts from Monascus samples significantly enhanced CTN cytotoxicity for HEK293 cells using the MTT assay. These results provide the first information about the cytotoxic effects of various Monascus samples and CTN-Monascus mixtures on a human cell line.  相似文献   
98.
Hair samples from the horse, elk, deer, moose, and antelope; subcutaneous tissue from the moose and antelope; and cast and living skin of the rattlesnake were activated by exposure to a neutron flux. The resulting products were studied by pulse-height analysis. Differences in type and proportion of trace elements appear to be consistent within the species studied.  相似文献   
99.
采集中国红壤、黑土、褐土、棕壤和黄壤五种典型土壤,经一个月老化制备成浓度为600 mg·kg–1的砷污染土壤样品,利用体外(in vitro)试验方法(PBET-UF模型)研究经口部摄入的土壤砷在人体胃肠道的生物可给性/生物有效性,并评估其健康风险,进而从土壤性质角度(包括土壤基本理化特性及砷的赋存形态)综合地探讨砷的生物可给性/生物有效性的影响因素,以分析不同土壤间差异的原因。结果表明,土壤砷在胃阶段的生物可给性为37.2%~71.8%,小肠阶段的生物可给性为49.0%~73.3%,小肠阶段的生物有效性为48.6%~72.1%,各类型土壤间差异极显著;土壤砷从胃到小肠是一个逐步被消化溶出的过程,且小肠中溶解态砷均可透过模拟小肠上皮细胞的专用超滤膜;各类型土壤经口部摄入的砷健康风险存在极显著差异,致癌风险和非致癌风险分别超过相应可接受限值两个数量级和一个数量级;此外,土壤砷的生物可给性/生物有效性与土壤pH、游离氧化铁铝含量、迁移系数S及迁移系数W存在显著或极显著相关性,迁移系数S是影响土壤砷在胃阶段的生物可给性的主导因子,土壤pH为影响其在小肠阶段的生物可给性/生物有效性的主导因子,...  相似文献   
100.
OBJECTIVE: To evaluate the in vitro antifungal properties of silver sulfadiazine (SSD) and natamycin against filamentous fungi isolated from eyes of horses with keratomycosis. SAMPLE POPULATION: Filamentous fungal isolates obtained from eyes of keratomycosis-affected horses. PROCEDURES: Fungal culture of ocular samples yielded 6 Fusarium spp; 7 Aspergillus spp; and 1 isolate each of Curvularia, Scopulariopsis, Penicillium, and Chrysosporium. For each fungal isolate, minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of SSD and natamycin were determined. RESULTS: For all 17 fungal isolates, SSD MIC distribution ranged from < or = 1 to > 64 microg/mL; MIC50 and MIC90 (MICs at which 50% and 90% of organisms were inhibited) were 4 and 32 microg/mL, respectively. The SSD MFC distribution for all isolates was < or = 1 to > 64 microg/mL; MFC50 and MFC90 (MFCs at which 50% and 90% of organisms were killed) were 8 and > 64 microg/mL, respectively. For all fungal isolates, natamycin MIC distribution ranged from 256 to > 1,000 microg/mL; MIC50 and MIC90 were 512 and > 1,000 microg/mL, respectively. The natamycin MFC distribution for all isolates ranged from 512 to > 1,000 microg/mL; MFC(50) and MFC(90) were each > 1,000 microg/mL. CONCLUSIONS AND CLINICAL RELEVANCE: These in vitro data suggest that SSD is fungicidal against the fungal isolates that were obtained from eyes of horses with keratomycosis and that natamycin is fungicidal against some of the isolates at the drug concentrations evaluated. Silver sulfadiazine may be a therapeutic option for equine keratomycosis.  相似文献   
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