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81.
Firefly luciferase exposed to a temperature of 135 degrees C for 36 hours re tained up to 40 percent of its original activity. Prerequisites for heat stability were the use of a molecular sieve (Seph adex G-25 or Biogel P-300) and a high vacuum (5 x 10(-4) mm-Hg). These studies present a possible solution to the problem of sterilization for exobiologi cal experiments. 相似文献
82.
Mary Leissinger João Brandão Nobuko Wakamatsu Alexandre Le Roux Gregory Rich Stephen Gaunt 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2013,42(3):364-367
An approximately 8‐year‐old male castrated Dutch rabbit was evaluated for a 6‐day history of respiratory signs, which began as sneezing and progressed to tachypnea with anorexia. On physical examination, tachypnea and pale mucous membranes were noted. Thoracic radiographs revealed a soft tissue pulmonary mass, fine‐needle aspirates of which confirmed a neoplasia with malignant features suspicious for a histiocytic sarcoma. The rabbit was discharged and due to a rapidly deteriorating condition, the owner declined chemotherapy with Lomustine and elected euthanasia of the rabbit. The affected lung was submitted for histopathology. Histologic sections of the lung were characterized by clusters of histiocytic cells and multinucleated giant cells with occasional invasion of blood and lymphatic vessels. The histologic diagnosis was histiocytic sarcoma. To the authors' knowledge, this is the first case report of histiocytic sarcoma in a rabbit. Based on the clinical and radiologic findings in this case, histiocytic sarcoma should be included in the list of differentials for rabbits presenting with respiratory signs and evidence of a pulmonary mass. 相似文献
83.
Won-Il Kim Jae-Jo Kim Sang-Ho Cha Wai-Hong Wu Vickie Cooper Rich Evans En-Jin Choi Kyoung-Jin Yoon 《Veterinary microbiology》2013
A high rate of genetic and antigenic variability among porcine reproductive and respiratory syndrome viruses (PRRSVs) hampers effective prevention and control of the disease caused by PRRSV. The major envelope protein (GP5) encoded by the ORF5 of PRRSV has a critical role in inducing virus neutralizing (VN) antibody and cross protection among different strains of PRRSV. This study was conducted to identify sequence elements related to cross neutralization by comparing the ORF5 sequences of 69 field isolates in conjunction with their susceptibility to VN antibody raised against the VR2332 strain in vitro and in vivo. Five common variable sites (amino acid position 32–34, 38–39, 57–59, 137 and 151) were identified between susceptible and resistant viral isolates. Mutants whose ORF5 amino acid sequences were substituted with the sequences corresponding to the 5 identified common variable sites individually or concurrently were generated from a VR2332-backboned infectious clone by site mutagenesis. The change in the susceptibility of the mutants to VN antibodies specific for VR2332 or a heterologous PRRSV was assessed to determine the association of those 5 identified sites with cross neutralization. Among the five sites, the changes of amino acid sequences at three sites (32–34, 38–39, and 57–59) located in the N-terminal ectodomain of ORF5 significantly influenced the susceptibility of the mutant viruses to VN antibody, suggesting that sequence homology at these sites can be utilized as genetic markers to predict the degree of cross neutralization among different PRRSVs. 相似文献
84.
A Mubarak CP Bondonno AH Liu MJ Considine L Rich E Mas KD Croft JM Hodgson 《Journal of agricultural and food chemistry》2012,60(36):9130-9136
There is mounting evidence that specific dietary polyphenols can enhance vascular health by augmenting nitric oxide. Our aim was to investigate the acute effects of chlorogenic acid, an important dietary phenolic acid present in coffee (400 mg, equivalent to 2 cups of coffee), on nitric oxide status, endothelial function, and blood pressure. Healthy men and women (n = 23) were recruited to a randomized, double-blind, placebo-controlled, crossover trial. Chlorogenic acid resulted in significantly higher plasma concentrations of chlorogenic acid (P < 0.001). Relative to control, the mean post-treatment systolic blood pressure (-2.41 mmHg, 95% CI: -0.03, -4.78; P = 0.05) and diastolic blood pressure (-1.53 mmHg, 95% CI: -0.05, -3.01; P = 0.04) were significantly lower with chlorogenic acid. Markers of nitric oxide status (P > 0.10) and the measure of endothelial function (P = 0.60) were not significantly influenced. Chlorogenic acid can lower blood pressure acutely, an effect that, if sustained, would benefit cardiovascular health. 相似文献
85.
Plants, RNAi, and the Nobel Prize 总被引:1,自引:0,他引:1
Jorgensen R 《Science (New York, N.Y.)》2006,314(5803):1242-1243
86.
Ricardo Jorge Soares Magalh?es Anette Loeffler Jodi Lindsay Mick Rich Larry Roberts Heather Smith David Hugh Lloyd Dirk Udo Pfeiffer 《Veterinary research》2010,41(5)
Risk factors for methicillin-resistant Staphylococcus aureus (MRSA) infection in dogs and cats were investigated in an unmatched case-control study. A total of 197 animals from 150 veterinary practices across the United Kingdom was enrolled, including 105 MRSA cases and 92 controls with methicillin-susceptible S. aureus (MSSA) infection. The association of owners and veterinarian staff with the human healthcare sector (HCS) and animal-related characteristics such as signalment, antimicrobial and immunosuppressive therapy, and surgery were evaluated as putative risk factors using logistic regression. We found that significant risk factors for MRSA infection were the number of antimicrobial courses (p = 0.005), number of days admitted to veterinary clinics (p = 0.003) and having received surgical implants (p = 0.001). In addition, the odds of contact with humans which had been ill and admitted to hospital (p = 0.062) were higher in MRSA infected pets than in MSSA controls. The risk factors identified in this study highlight the need to increase vigilance towards identification of companion animal groups at risk and to advocate responsible and judicious use of antimicrobials in small animal practice. 相似文献
87.
88.
Sapinder Bali Vidyasagar Sathuvalli Chuck Brown Rich Novy Lorie Ewing Jeanne Debons David Douches Joseph Coombs Duroy Navarre Jonathan Whitworth Brian Charlton Solomon Yilma Clinton Shock Jeff Stark Mark Pavek N. Richard Knowles 《American Journal of Potato Research》2017,94(1):54-63
The Northwest Potato Variety Development (NWPVD) Program has released 45 improved potato varieties since 1985. Thirty-four potato varieties, four breeding clones and two advanced selections from NWPVD Program, and six commonly-grown potato varieties were fingerprinted using 32 simple sequence repeat (SSR) markers and 12,808 single nucleotide polymorphism (SNP) markers. Of 32 SSR markers, 29 exhibited significant polymorphism across all the 46 potato clones studied. A total of 143 alleles were observed with an average of 4.6 alleles per SSR marker. These markers span all 12 chromosomes of potato, with a maximum of five markers from chromosome VIII and minimum of one marker from chromosome VI. The polymorphic information content (PIC) and expected heterozygosity (He) of the SSR markers ranges between 0.18 to 0.75 and 0.20 to 0.78, respectively. Based on PIC, He, and ease of scoring, we recommend a set of eight SSR markers: STG0016, STI0004, STI0012, STI0023, STI0030, STI0033, STM1016 and STM1104 for fingerprinting NWPVD varieties. Out of 12,808 SNPs, 88.8% resulted in reliable three cluster diploid calling of which 87.8% were polymorphic. Tetraploid calling resulted in 44.2% of SNPs of which 94.5% were polymorphic. Our study provided fingerprinting resources for the NWPVD varieties and can be used in issues related to intellectual property rights, ownership, trademark and diversity analysis. 相似文献
89.
90.