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991.
In preparing this document the Authors aimed to pool current information on canine and feline mast cell disease. The information was gathered from international studies and a emphasis was placed on material and opinion with a strong evidence base. We intend it to form the basis of our understanding in this disease at the current time and we anticipate that it will be particularly useful for the general practitioner. It should be emphasized that the authors are presenting this work from a European perspective.  相似文献   
992.
Various types of intestinal intussusception were diagnosed in 29 of 220 young dogs with acute enteritis or gastroenteritis, due to canine parvovirus (85 cases) or presumably to other infectious agents, inflammation or less common hypermotility and metabolic derangements (135 cases). As the other causes of the disease were excluded, acute enteritis or gastroenteritis was considered to be the most likely predisposing factor for the intestinal intussusception. The most common type of intussusception was found to be the ileocolic. Of the 21 dogs that underwent surgical resection and anastomosis of the intestine, 18 dogs recovered completely and three died due to complications. The high survival rate was due to the effective pre-operative, surgical and post-operative therapy.  相似文献   
993.
Nitric oxide air pollution: detection by optoacoustic spectroscopy   总被引:6,自引:0,他引:6  
Nitric oxide is detected by a new technique in which tunable infrared radiation from a spin-flip Raman laser is used to measure the absorption spectrumn of a gas sample by optoacoustic spectroscopy. This technique is sensitive enough to detect a concentration of 0.01 part per million of nitric oxide pollution in air samples.  相似文献   
994.
Further studies of the Saturnian magnetosphere and planetary magnetic field by Voyager 2 have substantiated the earlier results derived from Voyager 1 observations in 1980. The magnetic field is primarily that of a centered dipole (moment = 0.21 gauss-RS(3); where one Saturn radius, RS, is 60,330 kilometers) tilted approximately 0.8 degrees from the rotation axis. Near closest approach to Saturn, Voyager 2 traversed a kronographic longitude and latitude range that was complementary to that of Voyager 1. Somewhat surprisingly, no evidence was found in the data or the analysis for any large-scale magnetic anomaly in the northern hemisphere which could be associated with the periodic modulation of Saturnian kilometric radiation radio emissions. Voyager 2 crossed the magnetopause of a relatively compressed Saturnian magnetosphere at 18.5 RS while inbound near the noon meridian. Outbound, near the dawn meridian, the magnetosphere had expanded considerably and the magnetopause boundary was not observed until the spacecraft reached 48.4 to 50.9 RS and possibly beyond. Throughout the outbound magnetosphere passage, a period of 46 hours (4.5 Saturn rotations), the field was relatively steady and smooth showing no evidence for any azimuthal asymmetry or magnetic anomaly in the planetary field. We are thus left with a rather enigmatic situation to understand the basic source of Saturnian kilometric radiation modulation, other than the small dipole tilt.  相似文献   
995.
Summary The EVIKA Research Centre has developed a disease eradication system for the initial material of seed potato, which consists of 1. Selection of the initial material for eradication, plant thermotherapy, meristem tip cultivation and testing for viruses; 2. Re-eradication (thermotherapy of test-tube plants, cultivation of meristem tips, testing for viruses, testing of varietal quality and yield of disease-free meristem clones, and the selection of meristem clones with best varietal characteristics; 3. Renewing of the initial material (all processes as above, but the initial material is selected from the seed potatoes grown for at least 3 years in the field). Field trials were conducted after the second cycle of eradiaction to determine whether the plantlets were true-to-type and to assess the yield, disease resistance and tuber dry matter. Recently we have also started in vitro testing of meristem plants resistance to late blight, hoping that this approach will improve the selection efficiency. Propagation and growing of the seed tubers consists of 3 main steps: 1. Plantlet propagation in vitro; 2. Greenhouse propagation in plastic rolls; and 3. Planting the first generation tubers in the field. Under our conditions it is the cheapest, simplest and most effective way. Multiplication of the meristem-derived plants is done by shoot tip cuttings in a greenhouse in plastic rolls with peat as the growing medium. The first generation of seed tubers is grown in the field. In our trials plant productivity was affected by the method of multiplication, growing conditions and genotype. The highest yield per hectare was obtained with plants multiplied in plastic rolls. The in vitro plants had more tubers per plant than plants multiplied in plastic rolls. In seed production fields the productivity of plants was more influenced by following our instructions than by multiplication and growing methods. The number of tubers per plant obtained with over 0.5 million plants was 6.5–9.0. In the second generation of seed tubers, grown under equal density, the greater-sized tubers gave more tubers with lower weight than the smaller-sized tubers. Cutting tubers had no effect on the plant development and tuberization.  相似文献   
996.
OBJECTIVE: To compare the sensitivity and positive predictive value of four methods for detection of oestrus in dairy cows with resynchronised oestrous cycles. PROCEDURE: Oestrous cycles in cows in three herds were synchronised for a first round of artificial insemination (AI) and then resynchronised for a second round of AI. Sensitivity and positive predictive value of four aids (pedometers, radiotelemetric transmitters [HeatWatch; HW], tail-paint and heatmount detectors) that were used to detect the resynchronised oestrus were compared. Milk progesterone concentration and pregnancy testing at 12 weeks were used as the reference standard for cows being in oestrus. RESULTS: The mean sensitivity and positive predictive value for detecting the resynchronised oestrus, for each aid that was used, was > 80%. Tail-paint was significantly more sensitive at detecting oestrus compared to heatmount detectors (P = 0.002), but not significantly more sensitive than pedometers (P = 0.07) or HW (P = 0.55) for detecting oestrus (91.3, 85.7; 81.4 and 88.4%, respectively). Positive predictive value of HW for detecting oestrus was greater than tail-paint (P = 0.014) and heatmount detectors (P = 0.024) but not pedometers (P = 0.25; 100, 91.7, 92.9 and 87.5%, respectively). Positive predictive value of heatmount detectors was greater than pedometers in herd C (93.4% vs 73.3%; P = 0.035) but not in herds A (95.0% vs 90.0%; P = 0.56) or B (90.8% vs 100%; P = 0.10). No other significant differences in sensitivity or positive predictive value of detection of oestrus were found between aids. CONCLUSION: Tail-paint, heatmount detectors, pedometers and HW provide a high sensitivity (> 80%) and positive predictive value (> 85%) of detecting oestrus in dairy cows with resynchronized oestrous cycles.  相似文献   
997.
OBJECTIVE: To evaluate accuracy of measuring plasma clearance of inulin as an alternative renal function test for estimation of glomerular filtration rate (GFR) in cats. ANIMALS: 10 cats, first studied with intact kidneys and subsequently studied following partial nephrectomy. PROCEDURE: Clearance studies were performed in 10 clinically normal cats; those same cats then underwent partial nephrectomy, and clearance studies were performed again. Plasma concentration of inulin was determined after administration at 50 mg/kg of body weight to cats while renally intact and 45 mg/kg after the partial nephrectomy. Plasma clearance of inulin (PCin) was determined by dividing the dose by the area under the plasma inulin concentration versus time curve. Results for PCin were compared with values obtained simultaneously for urinary clearance of exogenously administered creatinine (Ccr), a widely accepted method for measurement of GFR in cats with intact kidneys and cats with reduced renal mass. RESULTS: Results of PCin were strongly correlated (r2 = 0.912, P < 0.001) with Ccr. Repeatability of determination of PCin was similar to that of Ccr. Sensitivity and specificity of PCin were superior and equivalent to that of Ccr, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Determination of PCin provides a reliable estimate of GFR in cats and is a promising alternative to determining Ccr in cats.  相似文献   
998.
Paddy and Water Environment - In the arid lands covering Uzbekistan, furrow irrigation with low application efficiency is still widely used due to a lack of funds and shortage of labor. To save...  相似文献   
999.
An experiment was conducted to evaluate the effect of roasting whole soybean in the local level on their chemical composition, nitrogen fractions, in situ degradability, and feeding performance in crossbred (Karan Swiss and Karan Fries) dairy cows. Twelve lactating crossbred cattle (369.08 ± 17.53 kg body weight) were randomly divided into two groups on the basis of milk yield (10.18 kg/day) and day of calving (89 days) in a randomized block design. Cows were fed green maize fodder and concentrate mixtures with 1 kg raw soybean as fed basis (7.6% of total diet) in the control group, where as roasted soybean replaced raw soybean in the treatment group to make both diets isonitrogenous and isocaloric. The roughage to concentrate ratio was around 55:45 in both diets. The cows were housed in individual byres and fed experimental diet for 90 days. The total dry matter intake per animal in both groups was similar. The digestibility of dry matter, organic matter, crude protein, ether extract, and neutral detergent fiber was comparable in both groups. The average milk production and fat-corrected milk yield per day was similar during the trial. Milk fat, milk protein, and solids not fat content remained unaffected and similar in both groups. All the animals maintained their body weight in both groups. Thus, rumen bypassing of protein fractions at the present method of bypassing did not have the desired level of beneficial effect in medium producing crossbred cows.  相似文献   
1000.
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