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71.
Nanometer-sized silver (Ag+) particles (NS) are used in various applications as an anti-microbial. Effects of NS (2–5 nm diam.) pulse solution treatments on vase life of cut gerbera (Gerbera jamesonii) cv. Ruikou flowers were investigated. Compared with the control [pulsed with deionised water (DI) and subsequently held in DI] pulsing for 24 h with 5 mg/L NS solution followed by holding in DI maintained water uptake and extended vase life. From in vitro and microscopy assessments, NS pulse treatment inhibited bacteria growth in the vase solution and at cut stem ends during the first 2 d of the vase period.  相似文献   
72.
It is clear that the profession is not well prepared to respond to society's needs in bio-defense and public health. The imperatives that face the veterinary profession, as emphasized by the agenda for action conference deliberations that are reported in this issue of the journal, require action on many fronts, but possibly none more essential than to address how veterinary education needs to change to meet these challenges. Addressing these needs, participants at the agenda for action conference met in groups of 30 to 50 to shape approaches that would address these key questions. The 161 participants were broadly representative of government, private practice, corporate practice, organized veterinary medicine, and academia (Appendix A). Reported here are the results of those deliberations, with each of the seven sections written up by the discussion leader. Included in the participants were 20 students, representative of eight different veterinary colleges, who both participated in the group discussions and have presented their own report.  相似文献   
73.
The purpose of this study was to determine if colostrum-deprived foals with experimentally induced Rhodococcus equi pneumonia have a decreased severity of the disease and decreased mortality rate when given hyperimmune (HI) R. equi antibody plasma (R. equi titer at least 100 % and virulence-associated protein A [VapA] at least 10000) prophylactically versus when given normal equine plasma (R. equi titer less than 20 % and VapA less than 160). Sixteen colostrum-deprived foals (R. equi titer less than 5 %) each received normal equine plasma in the first 24 hours of life (R. equi titer less than 20 %). At 14 days of age, six foals were given normal equine plasma and 10 foals were given HI plasma. All foals were subsequently infected intrabronchially with a pathogenic strain of R. equi (2.5 x 10 sup 8; organisms) at 21 days of age. Repeated physical examinations, weight measurements, complete blood cell counts, fibrinogen measurements, and thoracic radiographs (ventrodorsal and lateral) were performed to help determine the severity of the disease. Foals given HI plasma had significantly higher R. equi ELISA titers (42.4 %) than those given normal plasma (20.9 %) on the day of experimental infection. Mortality rates and severity of disease were statistically similar (P >.05) for the groups. Although none of the foals was treated with antibiotics, several with severe R. equi pneumonia recovered. Either HI or normal equine plasma administered to foals in the first few weeks of life caused no adverse effects and may be protective against R. equi, although the exact constituent responsible for protection is undetermined and requires further investigation.  相似文献   
74.
An in situ system involving incubation of 60- to 80-g pieces of muscle at 4 degrees C under different conditions was used to determine the effects of time of postmortem storage, of pH, and of temperature on activities of mu- and m-calpain activity in bovine skeletal muscle. Casein zymograms were used to allow measurement of calpain activity with a minimum of sample preparation and to ensure that the calpains were not exposed to ionic strengths of 100 or greater before assay of their activities. In 4 of the 5 muscles (longissimus dorsi, lumbar; longissimus dorsi, thoracic; psoas major; semimembranosus; and triceps brachii) studied, mu-calpain activity decreased nearly to zero within 48 h postmortem. Activity of m-calpain also decreased in the in situ system used but at a much slower rate. Activities of both mu- and m-calpain decreased more slowly in the triceps brachii muscle than in the other 4 muscles during postmortem storage. Although previous studies have indicated that mu-calpain but not m-calpain is proteolytically active at pH 5.8, these studies have used calpains obtained from muscle at death. Both mu- and m-calpain are proteolytically inactive if their activities are measured at pH 5.8 and after incubating the muscle pieces for 24 h at pH 5.8. Western analysis suggested that neither the large 80-kDa subunit nor the small 28-kDa subunit of m-calpain was autolyzed during postmortem storage of the muscle pieces. As has been reported previously, the 80-kDa subunit of mu-calpain was autolyzed to 78- and then to a 76-kDa polypeptide after 7 d postmortem, but the 28-kDa small subunit was not autolyzed; hence, the autolyzed mu-calpain molecule in postmortem muscle is a 76-/28-kDa molecule and not a 76-/18-kDa molecule as previously assumed. Because both subunits were present in the postmortem calpains, loss of mu-calpain activity during postmortem storage is not due to dissociation of the 2 subunits and inactivation. Although previous studies have shown that the 76-/18-kDa mu-calpain molecule is completely active proteolytically, it is possible that the 76-/28-kDa mu-calpain molecule in postmortem muscle is proteolytically inactive and that this accounts for the loss of mu-calpain activity during postmortem storage. Because neither mu- nor m-calpain is proteolytically active at pH 5.8 after being incubated at pH 5.8 for 24 h, other proteolytic systems such as the caspases may contribute to postmortem proteolysis in addition to the calpains.  相似文献   
75.
76.
BACKGROUND: L-Lactate has been used as a prognostic indicator for ill humans and animals. A portable analyzer that measures L-lactate could help veterinarians decide to proceed with correction of a displaced abomasum. HYPOTHESES: The likelihood of a dairy cow with a displaced abomasum remaining in the herd can be predicted by lactate concentration and other variables. ANIMALS: Thirty-four healthy early-lactation dairy cows, and 131 cows with abomasal displacements (DA) presented to Cornell University, Ithaca, NY. METHODS: Plasma L-lactate was measured using a commercial analyzer (i-STAT). A cow had a positive outcome (PO) if she remained in the herd 30 days after surgical correction of the displaced abomasum and a negative outcome (NO) if she was culled or died in that time. A multivariable model with physical examination and clinicopathologic variables for predicting NO for cows with right-sided abomasal displacements was constructed. RESULTS: The median plasma L-lactate was 0.54 mM/L (interquartile range, 0.42-0.74) in healthy lactating Holstein cows. In cows with right-sided displaced abomasa, median plasma L-lactate concentrations were higher in cows with NO (5.88 mM/L) versus PO (3.23 mM/L) (P = .002). In a multivariable model, which identified chloride, heart rate, and L-lactate as the best fitting variables for cows with right-sided displacements, the probability of NO increased as L-lactate increased. CONCLUSIONS AND CLINICAL IMPORTANCE: Plasma L-lactate concentration might be a useful predictor of productive outcomes in cows with right-sided abomasal disorders.  相似文献   
77.
The major anthocyanins of boysenberry fruit, a cross between Rubus loganbaccus and Rubus baileyanus Britt., were isolated by preparative high-performance liquid chromatography (HPLC). The structures of cyanidin-3-[2-(glucosyl)glucoside] (1) and cyanidin-3-[2-(glucosyl)-6-(rhamnosyl)glucoside] (2) were determined by NMR in 1% DCOOD/D(2)O. An unusually high chemical shift (delta 2.5) is reported for H-5' ' of cyanidin-3-[2-(glucosyl)glucoside].  相似文献   
78.
Species distributions are influenced by many processes operating over varying spatial scales. The development of species distribution models (SDMs), also known as ecological niche models, has afforded the opportunity to predict the distributions of diverse taxa across broad geographic areas and identify variables that are potentially important in regulating these distributions. However, the integration of site-specific habitat data with broad scale climate and landcover data has received limited attention in an SDM framework. We investigate whether SDMs developed with breeding pond, landcover, and climate variables can accurately predict the distributions of nine pond-breeding amphibians in eastern Missouri, USA. Additionally we investigate the relative influences of each environmental variable on the distribution predictions for each study species, and whether the most influential variables are shared among multiple taxa. Boosted regression tree (BRT) SDMs were developed for each species with 38 abiotic and biotic environmental variables, including data from the breeding ponds, surrounding landcover, and climate. To test the models, field surveys were performed in 2007 and 2008 at 103 ponds for nine amphibian species. BRT models developed with breeding pond, landcover, and climate data accurately predicted the occurrences of six of nine species across the study area. Furthermore, the presence of each species was best predicted by a unique combination of environmental variables. Results also suggest that landcover and climate factors may be more influential for species near the edge of their geographic ranges, while local breeding pond factors may be more important for species nearer to the center of their ranges.  相似文献   
79.
BACKGROUND: Phagocytic activity of neonatal foals has been reported to be similar to that of adult horses, but serum opsonization capacity develops with age and may be further altered when opsonins are consumed during infection. HYPOTHESIS: Phagocytosis, oxidative burst activity, and serum opsonization capacity in neonatal foals admitted to an intensive care unit are reduced in comparison with control foals. ANIMALS: Blood samples were collected from hospitalized neonatal foals and from control foals. Hospitalized foals were characterized as sick or septic on the basis of a sepsis score and received intravenous plasma transfusion. METHODS: Phagocytosis, oxidative burst activity, and serum opsonization capacity were tested with flow cytometric analysis. Serum immunoglobulin and complement component 3 concentrations were determined with radial immunodiffusion. Serum amyloid A concentration was assayed with a commercially available solid-phase Sandwich ELISA Kit. Data were analyzed with nonparametric and regression methods. Alpha was set at P = .05. RESULTS: Phagocytic functions of septic and sick foals were lower than control foals in the initial phase of the study (P = .01). Opsonization capacity was significantly higher when bacteria were opsonized with serum from septic (P = .029) and sick (P = .006) foals than from control foals on day 1. Opsonization capacity in septic foals was comparable with control foals on days 2 and 5. This effect was not accompanied by an increase in serum complement C3 or immunoglobulin G concentrations independently. CONCLUSIONS AND CLINICAL IMPORTANCE: Our results suggest that phagocytic function could be decreased in hospitalized foals. The synergistic effect of opsonic elements provided by plasma transfusion may sustain opsonization capacity during sepsis.  相似文献   
80.
Preharvest sprouting is common in cereals, which lack grain dormancy when maturing grain is exposed to rainfall or high moisture conditions. Environmental conditions such as drought and high temperature during grain filling have a large effect on the expression of sprouting tolerance. A dormant (DM 2001) and non-dormant (Cunderdin) hard white spring wheat were exposed to drought or irrigated conditions and either low or high temperature during grain filling. Dormancy and embryo sensitivity to ABA were analysed throughout grain filling. The conclusions from this investigation were as follows; firstly DM 2001 was more dormant than Cunderdin, with a four-fold lower germination index (GI) at maturity. Secondly during grain ripening drought increased dormancy and overrides any increase in dormancy with low temperature. Finally embryo sensitivity can be induced in a non-dormant genotype to the extent where the non-dormant genotype in a hot dry environment can have the same phenotype as a dormant genotype grown in a cool wet environment. In summary drought during grain filling increases dormancy suggesting breeders need to avoid drought when screening for sprouting tolerance in order to maximise the chances of identifying genetic differences in grain dormancy and avoid any maturity by drought interactions.  相似文献   
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