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1.
C-reactive protein concentrations in canine acute pancreatitis   总被引:1,自引:0,他引:1  
Objective: To determine if C‐reactive protein (CRP) concentration is elevated in spontaneously occurring canine acute pancreatitis (AP), and to measure changes in CRP during the course of hospitalization. Design: Prospective study. Setting: Tufts University School of Veterinary Medicine Foster Hospital for Small Animals. Animals: Sixteen client‐owned dogs with AP and 16 healthy controls. Interventions: Blood samples were obtained from the AP group on the day of diagnosis (Day 1), and on Days 3 and 5, unless the dog died or was discharged from the hospital. Blood was obtained from the control dogs once. Measurements and main results: Serum CRP was measured using a commercial immunoassay for each dog with AP and for healthy controls. Day 1 CRP concentrations were significantly higher in the AP group (56.1±12.7 μg/mL) compared with controls (2.8±1.3 μg/mL; P<0.001). For the 7 dogs that had samples collected on all 3 days, the mean CRP concentrations decreased significantly (P=0.043) over the 5 days of measurement. Of the 16 dogs with AP, 14 were discharged from the hospital and 2 were euthanized. Conclusions: Serum CRP concentrations were elevated in this group of 16 dogs with spontaneously occurring AP. In the 7 dogs that had measurements on all 3 days, the mean CRP concentration decreased from the day of diagnosis to the measurement made 5 days later.  相似文献   
2.
Trace minerals feeding had significant effects on sperm production and fertility with better absorption and proper utilization within the body for optimum reproductive function. Several studies have shown that more influenced trace elements in the diets of animals are copper (Cu) and zinc (Zn). Bucks showing deficiency of this mineral might affect the quality of semen production which in turn would affect the fertility. This experiment was thus designed to test the effects of organic Cu and Zn supplementation on antioxidants enzyme activities and sperm functional attributes in fresh semen of bucks. Forty bucks (n = 40, Aged 5 months) were assigned to ten groups of four animals in each group, supplemented (for a period of 8 months) with different levels of organic Zn: 20 mg (T2), 40 mg (T3) and 60 mg (T4), organic Cu: 12.5 mg (T5), 25 mg (T6), 37.5 mg (T7) and combined organic Zn and Cu: 20 + 12.5 mg (T8), 40 + 25 mg (T9), 60 + 37.5 mg (T10), respectively, per kg dry matter and no additional mineral diet (control; T1). One hundred and sixty semen samples were collected through electro‐ejaculator and analysed for sperm quantity, quality, acrosome intactness and plasma membrane integrity and correlated with the catalase, superoxide dismutase, glutathione peroxidase and glutathione reductase enzyme activities in seminal plasma. The results indicated organic Cu and zinc supplemented bucks produced more sperm cells, had higher sperm concentrations, maintained higher (< .01) sperm livability, plasma membrane and acrosome integrities, more motility and velocity. The increased antioxidant enzyme activities, reduced oxidative stress and lowered lipid peroxidation were positively correlated (< .05) with the sperm functional attributes. In conclusion, organic Cu and Zn supplement to male goats showed protective roles against oxidative damage and maintained better fresh semen characteristics.  相似文献   
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OBJECTIVE: To evaluate the effectiveness of 2 potential endothelin (ET)-1 antagonists in blocking the contractile responses of equine colonic vessels to increasing concentrations of ET-1. SAMPLE POPULATION: Mesenteric vessels from 6 clinically healthy horses. PROCEDURE: Colonic vessels (arterial and venous rings) were placed in organ baths with oxygenated Tyrode solution at 37 C. Each was attached to a force transducer interfaced with a polygraph, and 2 g of tension was applied and equilibrated for 45 minutes. Then, B-1 (PD 142893) and B-2 (PD 145065) ET-1 antagonists were tested. One ring from each vessel type was used as a control for determining concentration-response relationships of ET-1 (10(-10) to 10(-6)M). Three rings of each vessel type were incubated with 3 concentrations of each antagonist (10(-7), 10(-6), and 10(-5) M) for 30 minutes before ET induced contractions were determined. The maximum contractile response and pA2 values were determined. RESULTS: Vessels contracted in a concentration-dependent manner to ET-1. Arteries responded slowly but reached greater contractions. Veins responded immediately with sustained contractions. Both antagonists inhibited contractions in a concentration-dependent manner with significant differences at 10(-6) and 10(-5)M for arteries and 10(-5) M for veins. Complete blockade of contractions was observed with B-2 (10(-5)M). The pA2 values for B-1 were 8.26 and 6.82 for arteries and veins, respectively, whereas they were 8.25 and 7.21 for B-2. CONCLUSION AND CLINICAL RELEVANCE: Both antagonists effectively blocked ET-1-induced contractions of equine colonic vessels. Because B-2 is water soluble and caused complete blockade at 10(-5) M, it appears to be the preferred antagonist.  相似文献   
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Ninety-nine dogs diagnosed with generalized demodicosis were treated with milbemycin oxime. Cases diagnosed before two years of age were classified as juvenile-onset (53%) and those diagnosed after two years of age as adult-onset (47%). Dogs were considered cleared of mites when none could be demonstrated in scrapings and cured if no relapse was seen for 12 months. Eighty-five per cent (84/99) were cured with milbemycin oxime used for 1-6 months (mean 2.3 months) at a dosage of 0.5-1.6 mg kg-1 body weight (mean 0.75 mg kg-1). No significant difference in dosage or treatment time was seen between juvenile and adult cases. Chance of cure was significantly better in young animals (cured cases mean age 2.97 years) than in older animals (not cured cases mean age 8.02 years). Start of treatment early in the course of disease gave a significantly better chance of cure. Cases with severe pododemodicosis had less chance of a cure (9/11 not cured).  相似文献   
7.
Barley has for feeding purposes a shortage of essential amino acids, especially lysine, threonine, and methionine, and an excess of proline and glutamine. In the present study, we have introduced into barley an antisense construct against C-hordeins, the storage protein with the lowest nutritional quality. SDS-PAGE and reverse phase HPLC revealed a relative reduction in the amounts of C-hordeins and relative increases in the content of the other storage proteins. The five different lines analyzed had lower amounts of proline, glutamic acid/glutamine, and phenylalanine (up to 12%, 6%, and 9% reductions), while the lysine, threonine, and methionine content was increased with up to 16%, 13% and 11%. It is concluded that antisense mediated suppression of C-hordein synthesis may be a promising approach for improving the nutritional value of barley as a feed crop while at the same time reducing the environmental nitrogen load.  相似文献   
8.
The modem crop scientist has a large amount of available nucleotide sequence information to identify genes of potential agronomic importance. Using reverse genetic approaches, specific genes can be disrupted, and hypotheses regarding gene function directly tested in vivo. Although a number of reverse genetic methods have been introduced, many are limited in application because they are organism-specific, expensive, transgenic, or only transiently disrupt gene function. However, traditional mutagenesis using chemical mutagens has been widely used as a forward genetics strategy to create many new crop plant varieties at relatively low cost. Mutagens such as ethyl methanesulphonate (EMS) cause stable point mutations and thus produce an allelic series of truncation and missense changes that can provide a range of phenotypes (Greene et al., 2003). TILLING (targeting induced local lesions IN genomes) is a high-throughput reverse genetic strategy that combines traditional mutagenesis and SNP discovery methods (Colbert et al., 2001; McCallum et al., 2000). To identify mutations, target regions of-l.5 kb are amplified with fluorescently labeled gene specific primers. Heteroduplexes are then formed between wild-type and mutant strands, mismatches are cleaved by incubation with a single-strand specific nuclease,  相似文献   
9.
A method for mapping potentially acid sulfate soils in Jutland, Denmark is described. First the wetlands were outlined, using already existing topographic maps. Then 7900 profiles, evenly distributed over the wetland areas, were examined to point out areas with potentially acid sulfate soils. The method used to identify potentially acid sulfate material was, for carbonate-free samples, a pH-measuring at the sampling time and after the samples were inoculated with soil water extract from an acid sulfate soil and 2, 8 or 16 weeks of incubation. For carbonate-containing samples the pyrite content was compared to the acid-neutralizing capacity. A map was constructed showing the ratio of profiles containing potentially acid sulfate soil samples to total number of profiles examined within natural geographical wetland regions.The investigation showed that 35% of the wetlands in Jutland have a high frequency of potentially acid sulfate soils.  相似文献   
10.
During the dry season in the tropics, agriculture which is solely dependent upon rainfall as its source of water is frequently affected by soil moisture stress, resulting in crop failures. Farmers therefore depend mainly on other sources of limited water supply during this period, such as ground water. Soil moisture conservation measures, especially surface mulching with loppings and, occasionally, leaf litter and crop residues, are practised. Our objective was to study the decomposition and nitrogen (N) release from these plant materials under continuously wet, low moisture regimes, i.e. comparable to those which prevail in the mulches used in the agriculture. A greenhouse experiment was conducted with fresh, chopped leaves of six leguminous trees, wild sunflower and rice, which were spread as a mulch on a layer of soil. They were maintained at eight moisture levels (a total of between zero and 43l water m–2 applied over 8 weeks) by spraying water. Different optimal moisture requirements for the rapid decomposition of these species were observed. These were presumably determined by different physical and chemical properties of the leaves. The amount of water received to the mulches and their soluble polyphenolic and carbon (C) concentrations played an important role in determining the decomposition and the mode of N release under non-limiting conditions of leaf N. Specifically, the C concentration governed N release, while the effect of polyphenolics was important when their concentration was low, as a result of leaching under relatively high moisture regimes. Leaves with a high polyphenolic and C content, which were subjected to high leaching losses of these fractions, underwent a change in their N dynamics from net immobilization to mineralization. This study indicates that leaves with a fast rate of decomposition should be mixed with other species, leaves which decompose more slowly in order to increase the conservation of soil moisture and also improve the synchronization between N release from the mulch and its demand by crops. Received: 6 January 1997  相似文献   
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