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611.
In both greenhouse and field experiments, a relationship was evident between the organismVerticillium albo- atrum and the pinkeye disease of potatoes. The fungicide, benomyl, was used to controlVerticillium after 2 and 4 weeks of contact with young potato seedlings. The mature tubers formed on these seedlings had varying amounts of pinkeye, depending on the potato line or variety tested. Seedlings that were first seed treated with benomyl and then inoculated withVerticillium did not develop pinkeye.Rhizoctonia also induced or stimulated pinkeye development.  相似文献   
612.
Belchip, a round white, widely adapted potato variety, especially useful for chips, was released by the U.S. Department of Agriculture, the Agricultural Experiment Stations of Florida, New Jersey, and Maine, and the Virginia Truck and Ornamental Research Station, Norfolk in 1978. Belchip is immune to viruses A and X and tuber net necrosis caused by the leaf roll virus; highly resistant to race O of late blight and tuber necrosis caused by high soil temperatures; and has not shown unusual susceptibility to other major potato diseases. Maturity is about 5 days later than Atlantic. Tubers of Belchip are flat round in shape with shallow eyes. Tubers may be irregular in conformation under nitrogen deficiency and water stress. Total solids content ranges from 18 percent in Florida to 23 percent in Maine. Chips made from Belchip were lighter in color than those processed from varieties currently grown along the Atlantic Seaboard. Belchip reconditions readily in 2–3 weeks from 4°C (39°F) storage.  相似文献   
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614.
Significant differences in tuber glycoalkaloid (TGA) content were found among five commercial varieties and B5141-6 grown at 39 different locations in 28 states. Line B5141-6 had the highest average TGA content, 29.3 mg/100 g in 1970 and 28.1 mg/100 g in 1971. Average TGA contents in 1970 of Kennebec, Russet Burbank, Katahdin, Irish Cobbler, and Red Pontiac were 9.7, 7.9, 7.9, 6.2, and 4.3 mg/100g, respectively. There were also significant location effects. Possible causes of high TGA levels are discussed.  相似文献   
615.
Effective troubleshooting for a diabetic small animal patient starts with the initial diagnosis of diabetes. Preempting trouble with a thorough and complete history, physical examination, laboratory assessment, and extensive and thoughtful client education before discharge, are crucial first steps toward avoiding trouble altogether. As problems arise, careful consideration of the many variables that contribute to effective diabetic control is necessary. As monitoring strategies evolve and treatment options expand, the clinician's ability to accurately assess and adjust the glycemic control in his or her troubled diabetic patient improves. Common causes of trouble in diabetic patients are reviewed and various strategies for the diagnosis and management of these disorders are discussed in this article. Every effort was made to draw from recently published reports of clinical cases. Few diseases will tie together owner, patient, and therapy as intimately as diabetes mellitus, and few problems will be solved without fully considering all potential factors.  相似文献   
616.
617.
The QRS response of the electrocardiogram to bleeding has been a source of interest to the physiologist for more than a century. Studies in the dog, cat and chicken have shown a reduction in QRS amplitude in response to bleeding. This effect has been explained by the so-called Brody effect, in which the intraventricular mass of blood acts as a conducting medium, augmenting radial conduction, thus resulting in the subsequent reduction in QRS amplitude in conditions where the intraventricular mass of blood is reduced. The aim of this study was to evaluate whether the Brody effect will be present in the ovine heart and, furthermore, to evaluate if the right and left ventricles will demonstrate the same QRS change if the Brody effect is indeed present. This study clearly demonstrated that the Brody effect is present in the ovine heart. Furthermore, two unique aspects emanating from this study are firstly the fact that this is the first study to show that premature ventricular complexes are able to induce the Brody effect and, secondly that there is a very clear difference in the response of the right and the left ventricles when the Brody effect is induced in the ovine heart.  相似文献   
618.
The aim of this study was to evaluate the viability in the effect of open pulled straw (OPS) vitrification procedure of sheep embryos after direct transference. Embryos were produced in vivo and cryopreserved in slow freezing or OPS vitrification. The survival rates of cryopreserved embryos were compared to non-frozen standard pattern. In a first set of experiments, embryos at morula and blastocyst stages were dived in ethylene glycol (1.5 M) and frozen in an automatic freezer. After being thawed, they were directly or indirectly transferred to ewes recipient. A second group of embryos were drawn into OPS and plunged into liquid nitrogen after being exposed at room temperature for 1 min and 45 s in 10% EG plus 10% dimethyl sulphoxide (DMSO), then again for 30 s in 20% EG + 20% DMSO + 0.5 M sucrose. After being warmed, embryos were also directly transferred using a French mini straw as the catheter for the transplantation process or after in vitro dilution of cryoprotectants (two-step-process). No significant difference was observed among fresh, frozen or vitrified embryos on pregnancy rate (50.0%, 38.6% and 55.8%). However, when we evaluated only the direct transference, the pregnancy rate of OPS vitrified embryos was higher than that of frozen embryos (57.1% vs 34.8%) (p = 0.07). In addition, vitrified morulae had a higher pregnancy rate than the one with frozen embryos (64.0% vs 38.9%) (p = 0.07). Finally, our results indicate that OPS vitrification technique in association with direct transference improves the viability of sheep embryos with potential applications to field conditions.  相似文献   
619.
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