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排序方式: 共有358条查询结果,搜索用时 156 毫秒
81.
Gu S Rumpel S Zhou J Strotmeier J Bigalke H Perry K Shoemaker CB Rummel A Jin R 《Science (New York, N.Y.)》2012,335(6071):977-981
Botulinum neurotoxins (BoNTs) are highly poisonous substances that are also effective medicines. Accidental BoNT poisoning often occurs through ingestion of Clostridium botulinum-contaminated food. Here, we present the crystal structure of a BoNT in complex with a clostridial nontoxic nonhemagglutinin (NTNHA) protein at 2.7 angstroms. Biochemical and functional studies show that NTNHA provides large and multivalent binding interfaces to protect BoNT from gastrointestinal degradation. Moreover, the structure highlights key residues in BoNT that regulate complex assembly in a pH-dependent manner. Collectively, our findings define the molecular mechanisms by which NTNHA shields BoNT in the hostile gastrointestinal environment and releases it upon entry into the circulation. These results will assist in the design of small molecules for inhibiting oral BoNT intoxication and of delivery vehicles for oral administration of biologics. 相似文献
82.
S King C Favrot L Messinger T Nuttall J Steffan S Forster W Seewald 《Veterinary dermatology》2012,23(5):440-e84
Background – Hypersensitivity dermatitides (HD) are frequently suspected in cats, but there are few clinical studies on safe and effective treatments in the published literature. Objectives – To establish a safe and effective dose of ciclosporin in the treatment of feline HD. Animals – One hundred client‐owned cats with feline HD. Methods – Double‐blind study, with cats randomly assigned to receive ciclosporin at either 7.0 mg/kg once daily (n = 33) or 2.5 mg/kg once daily (n = 32) or a placebo (n = 35) for 6 weeks. Results – Mean Total Lesion Scores with 7.0 mg/kg ciclosporin were significantly lower than with 2.5 mg/kg ciclosporin (P = 0.0047) or placebo (P = 0.0003) at study end. Individual Total Lesion Scores improved by >50% in 70% of the 7.0 mg/kg group, compared with 47% in the 2.5 mg/kg group and 23% in the placebo group (P = 0.0006). The investigators’ Global Assessment of Improvement was ‘excellent’ or ‘good’ in 61% of cats treated with 7.0 mg/kg ciclosporin, compared with 47% of cats given 2.5 mg/kg and 23% given placebo. The improvement in Investigator Pruritus Scores was significantly greater in cats treated with 7.0 mg/kg ciclosporin (54%) compared with both 2.5 mg/kg ciclosporin (32%; P = 0.0232) and placebo (21%; P = 0.0063). Mild gastrointestinal disorders were the most common adverse events, but these did not require cessation of therapy. Conclusions and clinical importance – Results suggest that 7.0 mg/kg ciclosporin once daily in food or per os for 6 weeks is effective and well tolerated in feline HD. 相似文献
83.
Céline Charpin Sophie Mahé André Keranflec’h Catherine Belloc Roland Cariolet Marie-Frédérique Le Potier Nicolas Rose 《Veterinary research》2012,43(1):69
The time-dependent transmission rate of Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) and the correlation between infectiousness, virological parameters and antibody responses of the infected pigs were studied in experimental conditions. Seven successive transmission trials involving a total of 77 specific pathogen-free piglets were carried out from 7 to 63 days post-inoculation (dpi). A semi-quantitative real time RT-PCR was developed to assess the evolution of the viral genome load in blood and nasal swabs from inoculated and contact pigs, with time. Virus genome in blood was detectable in inoculated pigs from 7 to 77 dpi, whereas viral genome shedding was detectable from nasal swabs from 2 to 48 dpi. The infectiousness of inoculated pigs, assessed from the frequency of occurrence of infected pigs in susceptible groups in each contact trial, increased from 7 to 14 dpi and then decreased slowly until 42 dpi (3, 7, 2, 1 and 0 pigs infected at 7, 14, 21, 28 and 42 dpi, respectively). These data were used to model the time-dependent infectiousness by a lognormal-like function with a latency period of 1 day and led to an estimated basic reproduction ratio, R0 of 2.6 [1.8, 3.3]. The evolution of infectiousness was mainly correlated with the time-course of viral genome load in the blood whereas the decrease of infectiousness was strongly related to the increase in total antibodies. 相似文献
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86.
OBJECTIVE: To examine and analyse consumption changes over time of 24 food items between Sardinia and Malta. SETTING: The data were collected in 2001 in Sardinia and 2002 in Malta. DESIGN: A structured qualitative questionnaire, articulated around four main themes: food supply, transformation, preparation and consumption habits, was administered by face-to-face interviews with the help of a local person. It encompassed mainly open-ended questions, which allowed us to measure factors contributing to change. SUBJECTS: Thirty mother-daughter pairs were interviewed in each insular territory. RESULTS: Despite a common trend revealing a shift away from cereals, pulses and potatoes to the benefit of meat products, fats and sugar, our results showed contrasting evolutions in food consumption between both insular societies. Fruit and vegetables, olive oil and fish, which are part of the main features of the Mediterranean diet, were among the top foods for which consumption frequency has increased in Sardinia. In Malta, besides an increase in olive oil and vegetable consumption, cheeses and desserts showed the highest increase. Along with modernity and improved living conditions, enhanced commercial availability and increased diversity of food preparation were also identified as factors contributing to food consumption changes. CONCLUSIONS: Although the Sardo-Mediterranean model is evolving under the impact of modernisation, it is not disappearing. In Malta, however, modernity has led to a more sudden shift from a state of food shortage to one of affluence, but in a cultural context where the identity is no longer Mediterranean but Anglo-Saxon. 相似文献
87.
88.
We conducted a processing plant survey to determine the prevalence of cellulitis (enlarged sternal bursa) and focal ulcerative dermatitis (FUD) in Ontario turkeys during the summer and to establish whether the two conditions were associated. A total of 11,772 birds from 24 different farms were observed at three processing plants in Ontario between June and August 2001. Each bird was examined for the presence of cellulitis and FUD. The severity and location of lesions were also noted. The overall prevalence of severe cellulitis (requiring either extensive trimming or condemnation of the bird) was 8.8% (95% confidence interval [CI] = 6.7, 10.9) and the overall prevalence for FUD was 22.6% (19.3, 25.9). The Pearson correlation coefficient between the prevalences of the two lesions was 0.56 (P = 0.0043), suggesting farms with a high prevalence of FUD in their birds also had a high prevalence of cellulitis. More specifically, birds with FUD were, on average, 10.8 times more likely to have cellulitis than birds without FUD (Mantel-Haenszel summary odds ratio = 10.8; 95% CI = 9.5, 12.3). Our observations suggest FUD may predispose birds to cellulitis, in which case, preventing FUD may reduce the occurrence of cellulitis condemnations in turkeys. 相似文献
89.
Trends in cellulitis condemnations in the Ontario chicken industry between April 1998 and April 2001
We conducted a retrospective study to determine the prevalence of cellulitis condemnations in the Ontario chicken industry and the relative proportion of variation attributable to factors that vary between processors, producers, and lots and over time. The time span studied was April 1998 to April 2001. We obtained condemnation data randomly from the Chicken Farmers of Ontario and analyzed the data with a generalized mixed model. The (weighted) average prevalence of cellulitis in Ontario between April 1998 and 2001 was 0.94% (0.87%, 1.03%). The prevalence of cellulitis ranged from 0% to 14.9%, with one outlier at 30% and 95% of the data between 0 and 2.58%. The final mixed model we used to describe the variation in the prevalence of cellulitis between lots included random effect terms, the plant where the birds were processed, the producer, the quota period when the birds were processed, and the interaction term quota period by processing plant, as well as fixed effects terms, the type of inspection system and the average weight of the birds. The final model containing these variables explained approximately 78% of the total variation in the data. Our findings indicate all three random effects variables accounted for a significant amount of variation in the cellulitis data; however, the greatest source of variation was ascribed to the plants where the birds were processed. Some of the variation in cellulitis associated with processing plants was explained by the type of inspection system used by the plant, but even after controlling for this factor, there remained a relatively large amount of variation between processing plants (approximately 30%). These findings suggest there may be discrepancies in the diagnoses of the condition. Some of the variation in the prevalence of cellulitis (approximately 13%) was also attributed to the producer; however, more of the variation in the data was attributed to differences in lot-specific factors (approximately 22%). Therefore, future control efforts for cellulitis should focus on standardizing the classification of cellulitis at processing plants and identifying lot specific factors that may increase the risk of the condition. 相似文献
90.
Troncy E Junot S Keroack S Sammut V Pibarot P Genevois JP Cuvelliez S 《Journal of the American Veterinary Medical Association》2002,221(5):666-672
OBJECTIVE: To determine prevalence of adverse effects associated with epidural administration of morphine with or without bupivacaine in dogs and cats undergoing surgery and evaluate effects of epidural administration of morphine on postoperative pain severity. DESIGN: Retrospective study. ANIMALS: 242 dogs and 23 cats. PROCEDURE: Morphine with or without bupivacaine was administered prior to surgery with a Tuohy needle, spinal needle, or epidural catheter. In 18 dogs that underwent surgery twice, results of preemptive epidural administration of morphine with or without bupivacaine were compared with results of systemic administration of oxymorphone and ketoprofen. RESULTS: The delivered fraction of isoflurane was significantly lower in animals given morphine and bupivacaine than in animals given morphine alone. Analgesia was of significantly longer duration in dogs given morphine and bupivacaine than in dogs given morphine alone. During anesthesia, mild respiratory and cardiovascular depression was reported. Seven dogs and 2 cats had urine retention, and 2 dogs developed pruritus. Six dogs vomited when a second dose of morphine was given epidurally the day after surgery. Eight of 72 dogs had delayed hair growth. In 18 dogs that underwent surgery twice, the delivered fraction of isoflurane was significantly lower and the duration of analgesia was significantly longer when morphine with or without bupivacaine was given epidurally than when oxymorphone and ketoprofen were given. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that preemptive epidural administration of morphine with or without bupivacaine is a safe and effective method of inducing long-lasting analgesia in dogs and cats and is superior to standard management of postoperative pain with repeated injection of oxymorphone and ketoprofen. 相似文献