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991.
John G. Davison 《Pest management science》1976,7(5):429-435
Convolvulus arvensis is the most important species of bindweed in Britain. Established plants spread by means of lateral roots: establishment from seed and fragments of the underground growth is not important. The hormone weedkillers like 2,4-D and MCPA give good control in the year of treatment. With the correct dose and timing there is also good control in the year after treatment. Adding paraquat to 2,4-D reduces the effect in the year after treatment. Repeated annual treatment with high doses of chlorthiamid that prevent shoot growth for the entire season are no more effective against the underground growth than the standard dose of 2,4-D. Calystegia sepium spreads rapidly by rhizomes and stolons. It is more susceptible than C. arvensis to MCPB. 相似文献
992.
Chas. A. Mitchell L. F. Guerin John Robillard 《Canadian journal of veterinary research》1968,32(4):544-546
The decay rate of six strains of Influenza virus Type A of human origin and eight strains of avian origin were examined in aerosol form under fixed conditions of temperature and humidity. Strains of avian origin were demonstrated to have greater resistance to decay of viability. 相似文献
993.
994.
John A. Johnson Mrs. Yu-Yen Linko 《Plant foods for human nutrition (Dordrecht, Netherlands)》1964,11(2-4):256-268
Summary Organic compounds present in minute quantities are responsible for bread flavor profile. Organic acids, alcohols, esters and carbonyl compounds have been identified and estimated, quantitatively, by use of paper, column and vapor-phase chromatography. Because of the minute quantities of most organic flavor constituents, some system of extraction and concentration must be employed for successful analysis. Separation into classes and concentration is best accomplished by formation of derivatives. Developing solvents, carrier system, and techniques of chromatography must be carefully selected for each group of compounds. Success in the analysis of bread flavor constituents has been significant in recent years because of the development of chromatography techniques.
with 4 figs.
Contribution no. 424, Department of Flour and Feed Milling Industries, Kansas State Agricultural Experiment Station, Manhattan, Kansas, U.S.A. 相似文献
Zusammenfassung Die Geschmackseigenschaften von Brot werden durch in sehr geringen Mengen vorhandene organische Verbindungen bedingt. Mittels Papier-, Säulen- und Gaschromatographie wurden organische Säuren, Alkohole, Ester und Karbonylverbindungen ermittelt und mengenmäßig bestimmt. Die äußerst geringen Mengen der Mehrzahl der organischen Geschmackskomponenten können nur mit einer Methode, die Extraktion und Konzentration umfaßt, erfolgreich analysiert werden. Diese Trennung in Gruppen und Konzentration wird am besten über die Bildung von Sekundärverbindungen erreicht. Hierbei muß für jede Gruppe von Komponenten eine sehr sorgfältige Auswahl der Entwicklungslösungen, der Vektorsysteme und der chromatographischen Technik getroffen werden. Die bedeutenden Fortschritte der chromatographischen Techniken der letzten Jahre sind der Grund für die Erfolge auf dem Gebiete der Analyse der Geschmackskomponenten von Brot.
Résumé Des composés organiques, présents en très faible quantités, régissent le profil de saveur du pain. Des acides organiques, des alcools, des esters et des composés carbonyliques ont été identifiés, et évalués, quantitativement par chromatographie sur papier, sur colonne, et en phase vapeur. Du fait des faibles quantités de la plupart des composants organiques de saveur, un système d'extraction et de concentration doit être utilisé pour réussir les analyses. La séparation en classes et la concentration peut être obtenue de façon la meilleure par formation de dérivés. Les solvants de développement, les systèmes vecteurs, et les techniques de chromatographie, doivent être soigneusement selectionnés pour chaque groupe de composants. Les réussites dans le domaine de l'analyse des composants de la saveur du pain ont été significatives ces dernières années, du fait du développement des techniques chromatographiques,
with 4 figs.
Contribution no. 424, Department of Flour and Feed Milling Industries, Kansas State Agricultural Experiment Station, Manhattan, Kansas, U.S.A. 相似文献
995.
996.
Nutgrass tubers were planted in pots on thirteen occasions at 4-weekly intervals, and growth and development followed by sampling at 5-day intervals from 10 to 45 days after planting. Growth rates, final shoot numbers, dry weights and rhizome lengths, and new tuber production were highest in plantings made 1 and 29 March and 26 April. Correlation coefficients suggested that mean daylength during growth was a major factor influencing growth and development, but mean temperature appeared to be important in determining new tuber size and the proportion of dry-matter as new tubers. Shoot number appears to be a reliable guide to rhizome and tuber production. 相似文献
997.
Sherril L. Green Christopher B. Little John D. Baird Robert R. M. Tremblay Laura L. Smith-Maxie 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1994,8(2):128-132
The case records of 20 horses with tetanus referred to the Ontario Veterinary College-Veterinary Teaching Hospital between 1970 and 1990 were reviewed. The fatality rate was 75%. There was a strong association with previous vaccination and survival ( P = .03). Most of the animals had been injured an average of 9 days (range 2 to 21 days) prior to development of clinical signs. Hyperesthesia and prolapse of the third eyelid were the most common clinical signs. Treatment regimens varied during hospitalization; however, all horses received parenteral penicillin, tranquilizers, tetanus toxoid, and antitoxin. Five of the nonsurviving animals were given intrathecal tetanus antitoxin. One animal had seizures as a complication of intrathecal treatment. The prognosis was best for horses that (1) had been vaccinated prior to the injury, (2) responded to the phenothiazine tranquilizers, and (3) did not rapidly (over 24 to 48 hours) become recumbent. Considering the species susceptibility, potential for contaminated wounds, and the increased survival of vaccinated horses, yearly revaccination is recommended. 相似文献
998.
现代肉种鸡生产中 ,为预防猝死综合症( Sudden death syndrom,SDS)所需要的磷与钾量远高于其他生产过程所需量。建议 2 0~ 2 8周龄肉种鸡日粮至少应含钾 0 .65 % ,可消化磷0 .40 %。在过去 1年中 ,许多营养学家就肉种鸡的磷需要量作过综述。 Reddy( 2 0 0 1 )指出 ,0 .1 %的非植酸磷能保持肉种鸡最大生产性能和种蛋最大孵化率 ,而要维持最大骨骼强度 ,这个数字应为0 .2 %或 0 .3%。Wilson建议用非植酸磷代替植酸磷。 SDS多发于成年肉种鸡群中 ,尤其是那些大型肉种鸡品系 ,目前 ,大型肉种鸡约占世界肉鸡市场的 5 0 %。 SDS在 2 0世纪 8… 相似文献
999.
Linda B. Lehmkuhl Wendy A. Ware John D. Bonagura 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1994,8(1):2-17
Mitral stenosis was diagnosed in 15 young to middle-aged dogs. There were 5 Newfoundlands and 4 bull terriers affected, suggesting a breed predisposition for this disorder. Clinical signs included cough, dyspnea, exercise intolerance, and syncope. Soft left apical diastolic murmurs were heard only in 4 dogs, whereas 8 dogs had systolic murmurs characteristic of mitral regurgitation. Left atrial enlargement was the most prominent radiographic feature. Left-sided congestive heart failure was detected by radiographs in 11 dogs within 1 year of diagnosis. Electrocardiographic abnormalities varied among dogs and included atrial and ventricular enlargement, as well as atrial and ventricular arrhythmias. Abnormalities on M-mode and two-dimensional echocardiograms included abnormal diastolic motion of the mitral valve characterized by decreased leaflet separation, valve doming, concordant motion of the parietal mitral valve leaflet, and a decreased E-to-F slope. Increased mitral valve inflow velocities and prolonged pressure half-times were detected by Doppler echocardiography. Cardiac catheterization, performed in 8 dogs, documented a diastolic pressure gradient between the left atrial, pulmonary capillary wedge, or pulmonary artery diastolic pressures and the left ventricular diastolic pressure. Necropsy showed mitral stenosis caused by thickened, fused mitral valve leaflets in 5 dogs and a supramitral ring in another dog. The outcome in affected dogs was poor; 9 of 15 dogs were euthanatized or died by 2 1/2 years of age. 相似文献
1000.