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1.
Tropical Animal Health and Production - The aim of this study was to determine the prevalence and antimicrobial resistance of mecA and mecC methicillin-resistant Staphylococcus aureus (MRSA) in...  相似文献   
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Tropical Animal Health and Production - Avian influenza virus (AIV) H9N2 subtype is endemic in Iran and causes substantial economic loss to the growing poultry industry within the country. In this...  相似文献   
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Background: Cryptosporidium parvum is an important coccidian parasite infecting many mammals, including human. This parasite can manifest as chronic severe diarrhea in immunocompromised individuals, especially those with AIDS. The present study reports the recombinant production of rP2 and rP23 antigens of C. parvum as antigens for detecting human cryptosporidiosis using indirect ELISA tests. Methods:The coding sequences of rP2 and rP23 proteins were codon-optimized, commercially synthesized and sub-cloned in the pET28a expression vector. The expressed proteins were purified by Ni-NTA column chromatography and confirmed by Western blotting. The efficacy of rP2/rP23 proteins for serodiagnosis was evaluated by positive (n = 20) and negative (n = 20) human sera, confirmed by the Ziehl-Neelsen staining as the gold standard test. Results:In ELISA test, the sera from C. parvum-infected patients reacted strongly to rP2/rP23. The sensitivity and specificity related to the diagnostic potential of rP2/rP23 in the ELISA assay were 100%. Conclusion:Our results showed that combination of rP23 and rP2 antigens in ELISA significantly increases the performance of C. parvum serodiagnosis in human cryptosporidiosis. Key Words: Cryptosporidiosis, Enzyme-Linked Immunosorbent Assay, Western blotting  相似文献   
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The marine environment represents the largest ecosystem on the Earth’s surface. Marine-derived fungi are of remarkable importance as they are a promising pool of diverse classes of bioactive metabolites. Bergamotane sesquiterpenoids are an uncommon class of terpenoids. They possess diverse biological properties, such as plant growth regulation, phototoxic, antimicrobial, anti-HIV, cytotoxic, pancreatic lipase inhibition, antidiabetic, anti-inflammatory, and immunosuppressive traits. The current work compiles the reported bergamotane sesquiterpenoids from fungal sources in the period ranging from 1958 to June 2022. A total of 97 compounds from various fungal species were included. Among these metabolites, 38 compounds were derived from fungi isolated from different marine sources. Furthermore, the biological activities, structural characterization, and biosynthesis of the compounds are also discussed. The summary in this work provides a detailed overview of the reported knowledge of fungal bergamotane sesquiterpenoids. Moreover, this in-depth and complete review could provide new insights for developing and discovering new valuable pharmaceutical agents from these natural metabolites.  相似文献   
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使用1992年1月~2006年12月发行上市公司的数据,采用WLS方法,依据股权集中和股权分散两个不同的样本,得出了上市公司利用管理层持股传递公司价值信号的有效性依据其不同股权结构而不同的结论:在股权集中的公司中,管理层持股对IPO价值没有显著性影响;在股权分散的公司中,管理层的控制地位使得市场更愿意相信管理层在公司的股本能够传递公司的真实信号,管理层持股对IPO价值有显著性影响。  相似文献   
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This study investigated the effects of low potassium diets with different levels of Ca compared to two diets low in dietary cation–anion difference (DCAD) fed prepartum as a strategy to prevent hypocalcemia on sorting behaviour, total tract digestibility, oxidative status and energy and protein metabolism of transition cows. Forty-eight pregnant dairy cows were assigned to 4 treatment groups: Low Ca, low K (LCLK), High Ca, low K (HCLK), Supplementation with anionic mineral mixture (AMS) supplementation with SoyChlor (CAS). After parturition, all animals were fed a standard postpartum diet. Data were collected until 21 DIM. Prepartum urinary pH was significantly reduced by the low DCAD diets, while postpartum Ca homeostasis was affected by the HCLK ration. Feeding AMS induced sorting against particles <1.18 mm in favour of particles >19 mm prepartum. In contrast, cows fed CAS showed an increase in selective consumption of fine particles and sorted against longer particles similar to the HCLK and LCLK groups. Postpartum sorting activity was not affected by the dietary treatments. After calving, apparent digestibility of NDF was significantly reduced in the HCLK group. Prepartum, we observed effects on serum concentrations of non-esterified fatty acids were higher and insulin sensitivity was lower in the AMS group. Blood urea nitrogen (BUN) was decreased in cows fed the CAS ration. Postpartum, we found serum protein to be decreased with the low DCAD diets while BUN was decreased in the CAS group. The low DCAD rations increased prepartum serum malondialdehyde concentrations, while postpartum total antioxidant capacity was lower in the HCLK and the AMS group. From these data, we conclude that AMS decreased prepartum intake due to compromised palatability. Intermediate protein metabolism was affected by the low DCAD diets, while parameters of oxidative stress were probably affected by acid–base balance and Ca homeostasis.  相似文献   
9.
Bovine isoleucyl-tRNA synthetase (IARS) disorder, a major cause of weak calf syndrome, is caused by a homozygous missense (c.235G>C) mutation in the bovine IARS gene of Japanese Black (JB) cattle, which was identified in 2013. However, the extent to which the carrier rate has changed at Kagoshima prefecture, Japan, and whether the carrier status is associated with any clinical or reproductive problems, have yet to be ascertained. In this study, using a real-time polymerase chain reaction-based genotyping assay, we determined the carrier rate in a regional JB cow population at Kagoshima prefecture. Comparative analyses were performed on the metabolic profile test (MPT) results and reproductive performance data obtained for heterozygous carrier and homozygous wild-type cows. In 2009 and 2018, DNA samples were collected from 130 and 462 clinically healthy JB cows, respectively, in Kagoshima prefecture. MPT results and reproductive performance data were evaluated for 62 cows, comprising four heterozygous carriers and 58 wild-type cows. Genotyping revealed that the carrier rate was 6.9% in 2009 and 1.5% in 2018, the difference of which was statistically significant (P<0.005). There were no statistically significant differences between the carrier and wild-type cows with respect to either MPT results or reproductive performance, indicating that the carrier cows have necessary IARS activity to maintain minimal health and reproductive potential.  相似文献   
10.
Pre-conceptual sex selection is still a highly debatable process whereby X and Y chromosome bearing spermatozoa are isolated before oocyte fertilization. Recently, magnetic nanoparticles (MNP) have been used to determine X and Y chromosomes bearing spermatozoa as a result of searching for a cheap, highly efficient method using non-toxic materials. This study aimed to recover the sperm bearing X chromosomes in ram with different concentrations of MNP and then evaluate the success of this method using polymerase chain reaction (PCR). Ram sperms were divided into four groups, treated with 0 (control), 50, 100 and 200 μg/ml MNP, respectively. MNP was used to restore sperm cells bearing X chromosomes. Upon recovery, the PCR was performed to identify the X and Y sperms, Methyl ThiazoleTetrazolium (MTT), to assess MNP toxicity and sperm viability and acridine orange (AO) to evaluate sperm DNA integrity. The results of PCR revealed that the treatment of spermatozoa- bearing X chromosomes with 50 μg/ml MNP had the highest effects on the recovery of X sperm rather than the other concentrations of MNP. However, the concentrations of MNP did not have any toxic effects on spermatozoa, sperm viability and, DNA integrity, but the high concentration of MNP (200 μg/ml) significantly reduced DNA integrity. According to MTT and AO results, the concentrations of MNP used in this study had no toxic effects on spermatozoa and did not reduce the sperm viability and DNA integrity, except that 200 μg/ml MNP significantly reduced DNA integrity.  相似文献   
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