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Pérez-Hedo Meritxell Alonso-Valiente Miquel Vacas Sandra Gallego Carolina Pons Clara Arbona Vicent Rambla José L. Navarro-Llopis Vicente Granell Antonio Urbaneja Alberto 《Journal of pest science》2021,94(4):1221-1235
Journal of Pest Science - Modern agricultural policies across the globe are committed to a significant reduction in chemical pesticide dependency; however, pest management strategies are still... 相似文献
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Huang CH Mandelker D Schmidt-Kittler O Samuels Y Velculescu VE Kinzler KW Vogelstein B Gabelli SB Amzel LM 《Science (New York, N.Y.)》2007,318(5857):1744-1748
PIK3CA, one of the two most frequently mutated oncogenes in human tumors, codes for p110alpha, the catalytic subunit of a phosphatidylinositol 3-kinase, isoform alpha (PI3Kalpha, p110alpha/p85). Here, we report a 3.0 angstrom resolution structure of a complex between p110alpha and a polypeptide containing the p110alpha-binding domains of p85alpha, a protein required for its enzymatic activity. The structure shows that many of the mutations occur at residues lying at the interfaces between p110alpha and p85alpha or between the kinase domain of p110alpha and other domains within the catalytic subunit. Disruptions of these interactions are likely to affect the regulation of kinase activity by p85 or the catalytic activity of the enzyme, respectively. In addition to providing new insights about the structure of PI3Kalpha, these results suggest specific mechanisms for the effect of oncogenic mutations in p110alpha and p85alpha. 相似文献
955.
Matthew C. Leach Sandra Allweiler Claire Richardson John V. Roughan Ruediger Narbe Paul A. Flecknell 《Research in veterinary science》2009,87(2):336-347
This study aimed to develop a behaviour-based pain assessment system for rabbits following ovariohysterectomy. Behaviour was analysed to assess the severity and duration of pain induced and determine the effects of administration of meloxicam. The results suggest that pain associated with ovariohysterectomy induced changes in the frequency and duration of a number of behaviours. The most indicative was inactive pain behaviour, which was observed very infrequently prior to surgery compared to very frequently immediately following surgery. This strongly suggests that this increase is a direct response to the surgical pain and/or stress. The frequency of inactive pain behaviour also decreased over the four days post-surgery suggesting that pain is decreasing during this time. High dose meloxicam (initial 1 mg/kg followed 0.5 mg/kg/day) induced some degree of analgesia. However, higher doses of meloxicam or in combination with an opioid may be required to provide consistent analgesia in rabbits following soft-tissue surgery. 相似文献
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Cuevas JS Rodríguez-Ropón A Kennedy S Moreno-López J Berg M Hernández-Jáuregui P 《Veterinary immunology and immunopathology》2009,127(1-2):148-152
Selected lymphocyte subpopulations were studied and the distribution of viral mRNA were investigated during acute and persistent porcine rubulavirus (PoRV-LPMV) infection in Vietnamese pot-bellied pigs. Six pigs infected with PoRV-LPMV at 17 days of age exhibited clinical signs 7-10 days post-inoculation (pi). One infected piglet died 11 days pi while the other five recovered around day 13 pi and survived until euthanasia on day 277 pi. Increased numbers of CD8+, CD4+ and CD2+ T cells were detected during the acute phase of infection while CD8+ cells were elevated throughout the infection, including during the persistent stage. Specific antibodies against the haemagglutinin-neuraminidase protein of PoRV-LPMV were detected during persistent infection. Although infectious virus could not be recovered from tissues from any of the infected pigs at necropsy 277 days pi, PoRV-LPMV mRNA was detected in lymph nodes, pancreas and central nervous system using a nested polymerase chain reaction technique. Continued lymphocyte interaction with viral RNA may be an important factor in promoting cellular and humoral responses during persistent PoRV-LPMV infection. 相似文献
957.
Melissa N. Carr Sheila M. F. Torres Sandra N. Koch Lisa V. Reiter 《Veterinary dermatology》2009,20(2):105-110
There are numerous studies of the pruritus-producing effects of histamine, serotonin, tryptase, substance P and interleukin-2 in humans and mice, but very little reported in dogs even though a common reason dogs are presented to veterinarians is pruritus. The aim of this study was to determine whether substances known to cause pruritus in humans also cause pruritus in dogs. Twenty-five clinically healthy research beagle dogs were included in the study. All dogs first received an intradermal injection of 0.05 mL saline as a control substance and were video-recorded for 20 min before and after the injection. Twenty-four hours later the dogs were randomly divided into five groups of five dogs each and randomly assigned to receive histamine, serotonin, tryptase, substance P or interleukin-2 injected intradermally each at the volume of 0.05 mL. On subsequent days, increasing concentrations of each substance were used. Before (baseline) and after the injection of each concentration of the substances, the dogs were video-recorded for 20 min. The frequency and character of pruritus episodes (scratching, licking, chewing, rubbing or rolling) were noted and these data were used for statistical analysis. The number of pruritus episodes was compared among baseline, saline and the different concentrations of each substance. The results showed that dogs did not have a significant increase in pruritic behaviour above baseline or saline after injection of any of the investigated substances (generalized linear model; P = 0.23). 相似文献
958.
Melanocytic tumours are important in horses, especially grey horses. Intradermal common melanocytic naevi, cellular blue naevi and combined cellular blue naevi are subgroups of human melanocytic tumours, which have not been reported in horses. In this study, we describe 20 horses with skin tumours similar to these naevi of humans. These tumours represented individual skin masses in male and female horses of different breeds. Tumours resembling human intradermal common melanocytic naevi were noted in 12 horses aged between 2 and 17 years. Seven horses aged between 4 and 15 years developed cutaneous lesions similar to human cellular blue naevi. A combined cellular blue naevus-like tumour was diagnosed in a 20-year-old horse. All tumour types formed expansile, well-demarcated, non-encapsulated, symmetrical masses. Tumours similar to intradermal common melanocytic naevi were composed of nests of round and spindeloid neoplastic cells, often embedded in myxomatous stroma. Lesions resembling cellular blue naevi were formed by intradermal bundles of ovoid to elongated cells separated by collagen fibres. The combined cellular blue naevus-like tumour resembled human cellular blue naevus with in addition, an overlying junctional common melanocytic naevus. Neoplastic cells in all groups contained varying amounts of melanin pigment and were immunopositive for S100. These equine skin tumours differ from the commonly recognized equine melanocytic tumours by their cytomorphological features, random location and the absence of an increased tumour frequency in grey horses. The resemblance of these tumours to three distinct subgroups of human naevi expands the complexity of equine proliferative cutaneous melanocytic lesions. 相似文献
959.
Effects of drought on weed emergence and growth vary with the seed burial depth and presence of a cover crop 下载免费PDF全文
Stéphane Cordeau Sandra Wayman Carole Reibel Florence Strbik Bruno Chauvel Jean‐Philippe Guillemin 《Weed Biology and Management》2018,18(1):12-25
In conservation agriculture, weed seed germination could decrease with the presence of a cover crop, surface weed seed location and temporal drought in summer just after seed shedding. This study simultaneously examined the effects of a cover crop, burial depth (seed location) and hydric stress on weed emergence and early growth. It was hypothesized that drought would reduce weed emergence and the initial growth of weed seeds and that this effect would be greater when the seeds were on the soil surface and in the presence of a cover crop. Four annual weed species were chosen that are frequently found (Anisantha sterilis, Vulpia myuros, Sonchus asper, Veronica persica) and not frequently found (Alopecurus myosuroides, Poa annua, Cyanus segetum, Capsella bursa‐pastoris) in fields that implement conservation agriculture. The unburied seeds had 26% lower emergence, on average, than the buried seeds (significant for six of the eight species), hydric stress reduced emergence by 20% (for seven of the eight species) and the presence of a cover crop reduced the level of emergence by 17% (for all species). The unburied seeds with hydric stress were emerging under the “most stressful” set of factors, with a 45% decrease in emergence, compared with the seeds emerging under the “least stressful” set of factors (buried seeds without hydric stress). All the weed growth measurements (height, dry matter content and number of leaves) decreased with the presence of a cover crop. The species that are found frequently in the fields that implement conservation agriculture, compared with the species that are not frequently found in conservation agriculture fields, had higher rates of germination and a higher tolerance of hydric stress when their seeds were unburied. 相似文献
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Byeng Ryel Min Sandra Solaiman Thomas Terrill Aina Ramsay Irene Mueller-Harvey 《畜牧与生物技术杂志(英文版)》2015,6(1)