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991.
992.
McClenahan D Krueger R Lee HY Thomas C Kehrli ME Czuprynski C 《Comparative immunology, microbiology and infectious diseases》2006,29(2-3):127-137
Epithelial and endothelial cells play a pivotal role in initiating and controlling the movement of leukocytes into tissues during inflammation through the production of cytokines and chemokines such as interleukin-8 (IL-8). In situ hybridization with an IL-8 riboprobe was used to determine IL-8 mRNA expression by mammary gland epithelial and endothelial cells in cows with experimental Escherichia coli mastitis. Epithelial cells of the gland, especially surrounding the alveoli, had increased IL-8 mRNA levels at all time points at which tissue samples were collected (8, 12, and 24h) after E. coli challenge. Levels of IL-8 expression in the epithelial cells decreased at 24h post-infection. IL-8 expression by mammary gland endothelial cells was low, but did increase slightly at 24h post-infection. Both epithelial and endothelial cells of the mammary gland can contribute to the production of IL-8 that is typically seen in coliform mastitis. 相似文献
993.
Heald R 《Science (New York, N.Y.)》2006,311(5759):343-344
994.
1. Brown-egg pullets were reared on 8-h photoperiods and temporarily transferred at 80 d of age to 14-h photoperiods for 2, 4, 6, 8, 10 or 12 d. Controls were either maintained on 8 h or permanently transferred to 14 h at 80 d. 2. Pullets given 8 or 12 long days matured 8-9 d earlier than constant 8-h controls, but 22-23 d later than pullets transferred permanently to long days. Mean age at first egg for the groups given 2, 4, 6 or 10 d of 14-h days were not significantly different from the 8-h controls. The mean weight of first egg and body weight at first egg for the temporarily-photostimulated groups were not significantly different from constant 8-h controls, but egg weights were > or = 5.1 g and body weights at first egg > or = 200 g heavier than the birds transferred permanently to 14 h. 3. It is concluded that up to 6 temporary long days may be given (from 80 d of age) without affecting the timing of sexual maturity, but that the provision of 8 or more long days will accelerate sexual development, thought not to the extent of a permanent transfer, in most birds within a flock. A regression analysis of the ages at which the first and last birds in the groups given 6, 8, 10 or 12 long days matured suggested that about 20 d of photostimulation are required to achieve a mean age at first egg similar to that of birds permanently transferred to long days. 相似文献
995.
996.
Dowd PF Holmes RA Pinkerton TS Johnson ET Lagrimini LM Boston RS 《Journal of agricultural and food chemistry》2006,54(7):2629-2634
Tobacco (Nicotiana tabacum) plants grown from seed obtained by crossing a tobacco line that expressed an activated maize ribosome-inactivating protein (RIP) with a line that overexpressed tobacco anionic peroxidase were tested for their effects on corn earworm Helicoverpa zea and cigarette beetle Lasioderma serricorne larvae as compared to the wild-type plant cross. Significant feeding reductions were noted for transgenic plants expressing both resistance proteins as compared to wild-type plants for both H. zea and L. serricorne. Significant increases in mortality were also noted for those insects fed on the transgenic cross as compared to wild-type plants in some cases. Levels of both peroxidase and maize RIP were significantly higher in transgenic as compared to wild-type plants (which did not produce maize RIP). The degree of feeding was significantly negatively correlated with the level of RIP or peroxidase individually. 相似文献
997.
Moore GF Tapper K Murphy S Lynch R Raisanen L Pimm C Moore L 《Public health nutrition》2007,10(6):582-589
OBJECTIVES: To examine school-level relationships between deprivation and breakfast eating behaviours (breakfast skipping and the healthfulness of foods consumed) in 9-11-year-old schoolchildren and to examine whether attitudes towards eating breakfast mediated these relationships. DESIGN: Cross-sectional survey. SETTING: One hundred and eleven primary schools in Wales. SUBJECTS: Year 5 and 6 pupils within the 111 primary schools. Measures were completed by 4314 children. Analysis was conducted at the group (school) level, with each school representing one group. RESULTS: Deprivation was positively associated with breakfast skipping and consumption of 'unhealthy' items (i.e. sweet snacks, crisps) for breakfast. A significant negative association was found between deprivation and consumption of 'healthy' items (i.e. fruit, bread, cereal, milk). Deprivation was significantly inversely associated with attitudes towards eating breakfast. The relationships between deprivation and (1) breakfast skipping and (2) consumption of 'healthy' items for breakfast were mediated by attitudes towards eating breakfast. The hypothesis that attitudes mediated the relationship between deprivation and consumption of 'unhealthy' breakfast items was unsupported. CONCLUSIONS: Deprivation is associated with adverse breakfast eating behaviours amongst children aged 9-11 years, in terms of breakfast skipping and the quality of breakfasts consumed. Socio-economic differences in attitudes towards eating breakfast are apparent amongst this age group, and appear to relate to social gradients in breakfast eating behaviours. Research is needed to examine the causal nature of these trends and to elucidate factors underlying the development of socio-economic differences in eating-related cognitions. 相似文献
998.
Groenewald M Barnes I Bradshaw RE Brown AV Dale A Groenewald JZ Lewis KJ Wingfield BD Wingfield MJ Crous PW 《Phytopathology》2007,97(7):825-834
ABSTRACT Dothistroma septosporum and D. pini are the two causal agents of Dothistroma needle blight of Pinus spp. in natural forests and plantations. Degenerate primers amplified portions of mating type genes (MAT1-1-1 and MAT1-2) and chromosome walking was applied to obtain the full-length genes in both species. The mating-type-specific primers designed in this study could distinguish between the morphologically similar D. pini and D. septosporum and between the different mating types of these species. Screening of isolates from global collections of D. septosporum showed that only MAT2 isolates are present in Australian and New Zealand collections, where only the asexual form of the fungus has been found. In contrast, both mating types of D. septosporum were present in collections from Canada and Europe, where the sexual state is known. Intriguingly, collections from South Africa and the United Kingdom, where the sexual state of the fungus is unknown, included both mating types. In D. pini, for which no teleomorph is known, both mating types were present in collections from the United States. These results provided new insights into the biology and global distribution of two of the world's most important pine pathogens and should facilitate management of the diseases caused by these fungi. 相似文献
999.
Marla Lichtenberger DVM DACVECC ; Connie Orcutt DVM DABVP ; Carolyn Cray PhD ; Douglas H. Thamm VMD DACVIM ; Daniel DeBehnke MD FACEP ; Cheryl Page BSC CVT ; Lori Mull BSc CVT Rebecca Kirby DVM DACVIM DACVECC 《Journal of Veterinary Emergency and Critical Care》2009,19(5):467-472
Objective – The purpose of this study was to determine the LD50 for acute blood loss in mallard ducks ( Anas platyrhynchos ), compare the mortality rate among 3 fluid resuscitation groups, and determine the time required for a regenerative RBC response.
Design – Prospective study.
Setting – Medical College of Wisconsin Research facility.
Animals – Eighteen mallard ducks were included for the LD50 study and 28 for the fluid resuscitation study.
Interventions – Phlebotomy was performed during both the LD50 and fluid resuscitation studies. Ducks in the fluid resuscitation study received a 5 mL/kg intravenous bolus of crystalloids, hetastarch (HES), or a hemoglobin-based oxygen-carrying solution (HBOCS).
Measurements and Main Results – The LD50 for acute blood loss was 60% of total blood volume. This blood volume was removed in the fluid resuscitation study to create a model of acute blood loss. Following fluid administration, 6 birds in the crystalloid group (66%), 4 birds in the HES group (40%), and 2 birds in the HBOCS group (20%) died. No statistical difference in mortality rate was seen among the 3 fluid resuscitation groups. Relative polychromasia evaluated post-phlebotomy demonstrated regeneration starting at 24 hours and continuing through 48 hours.
Conclusions – The LD50 for acute blood loss in mallard ducks was 60% of their total blood volume. Although no statistical difference in mortality rate was appreciated among the 3 fluid resuscitation groups, a trend of decreased mortality rate was observed in the HBOCS group. An early regenerative response was apparent following acute blood loss. 相似文献
Design – Prospective study.
Setting – Medical College of Wisconsin Research facility.
Animals – Eighteen mallard ducks were included for the LD
Interventions – Phlebotomy was performed during both the LD
Measurements and Main Results – The LD
Conclusions – The LD
1000.
Stephen A. Simpson DVM Rebecca Syring DVM DACVECC Cynthia M. Otto DVM PhD DACVECC 《Journal of Veterinary Emergency and Critical Care》2009,19(6):588-602
Objective – To evaluate population characteristics, injuries, emergency diagnostic testing, and outcome of dogs with blunt trauma requiring intensive care in an urban hospital. Design – Retrospective study 1997–2003. Setting – All data obtained from the University of Pennsylvania – Matthew J. Ryan Veterinary Hospital. Animals – Dogs admitted to the intensive care unit for treatment following blunt trauma. Interventions – None. Measurements and Main results – Of the 235 dogs that met inclusion criteria, 206 (88%) survived and 29 (12%) did not survive. Blunt vehicular trauma accounted for 91.1% of cases. Mild hyperglycemia and hyperlactatemia was common in both survivors and nonsurvivors. The chest was the most common region traumatized and the prevalence of polytrauma was 72.3%. Initial weight, vital signs, PCV, total plasma protein, BUN, glucose, lactate, acid‐base status, and electrolytes did not differ between survivors and nonsurvivors. Nonsurvivors were significantly more likely to have had head trauma (P=0.008), cranium fractures (P<0.001), recumbency at admission (P<0.001), development of hematochezia (P<0.001), clinical suspicion of acute respiratory distress syndrome (P<0.001), disseminated intravascular coagulation (P<0.001), multiorgan dysfunction syndrome (P<0.001), development of pneumonia (P<0.001), positive‐pressure ventilation (P<0.001), vasopressor use (P<0.001), and cardiopulmonary arrest (P<0.001). Conclusions – Outcome of severe blunt trauma in dogs treated with intensive care is very good. Despite the high survival rate, several features associated with poor outcome were identified. Neither admission lactate nor glucose was able to predict outcome. 相似文献