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1.
Cellular alterations in level of expression of mRNA encoding for prostaglandin endoperoxide synthase were quantified within ovarian tissues of sheep obtained before, during and after induction of the preovulatory surge of LH and ovulation with LHRH. This was accomplished by isotopic in situ hybridization using a selective cRNA probe to ovine prostaglandin endoperoxide synthase mRNA. A significant elevation in mRNA was detected within the theca interna of the preovulatory follicle at 8, 16 and 24 hr following administration of LHRH. Very close to the time of ovulation (ie., at 24 hr post-LHRH) a marked rise in mRNA was observed in association with epithelial cells covering the apical surface of the follicle. Ovarian cyclooxygenase metabolites of arachidonic acid produced during the ovulatory process in the ewe originate within the thecal layer and germinal epithelium of the follicle destined to ovulate.  相似文献   
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Complementary DNA's that encode an adenylyl cyclase were isolated from a bovine brain library. Most of the deduced amino acid sequence of 1134 residues is divisible into two alternating sets of hydrophobic and hydrophilic domains. Each of the two large hydrophobic domains appears to contain six transmembrane spans. Each of the two large hydrophilic domains contains a sequence that is homologous to a single cytoplasmic domain of several guanylyl cyclases; these sequences may represent nucleotide binding sites. An unexpected topographical resemblance between adenylyl cyclase and various plasma membrane channels and transporters was observed. This structural complexity suggests possible, unappreciated functions for this important enzyme.  相似文献   
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Clinical and pathological features of ovarian dysgerminomas occurring in two dogs and a cat are presented. The feline neoplasm had morphological characteristics closely resembling those of dysgerminomas in women. The feline and one canine neoplasm occurred in young animals as compared to other reported animal dysgerminomas. Findings are discussed in relation to other reports of these tumors in animals and in women.  相似文献   
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Abstract

Extract

Trimethoprim became generally available 3 years ago, following its original discovery as a unique antibacterial agent for combating diseases of both man and animals (Hitchings and Bushby, 1961 Hitchings, G. H. and Bushby, S. R. M. 5-Benzyl-2, 4-diaminopyrimidines a new class of systemic anti-bacterial agents. 5th Int. Congr. Biochem. Moscow. pp.165165.  [Google Scholar]; Pugsley et al., 1969 Pugsley, D. G., Mwanje, L., Pearson, C and Blowers, R. 1969. Use of trimethoprim and sulphamethoxazole in tropical Africa: Typhoid fever; Salmonella typhi carriage and Staphylococcus aureus sepsis. Postgrad, med. J., 45: 9599. Nov. 1969, Suppl. [Google Scholar]; McGuinness, 1969 McGuinness, B. W. 1969. A combination of trimethoprim and sulphamethoxazole in upper respiratory infection. Postgrad, med. J., 45: 99101. Nov. 1969, Suppl. [Google Scholar]; McCaig, 1970 McCaig, J. 1970. A clinical trial using trimethoprim-sulphadiazine in dogs and cats. Vet. Rec., 87: 265265.  [Google Scholar]; Barnett and Bushby, 1970 Barnett, Margaret and Bushby, S. R. M. 1970. Trimethoprim and the sulphonamides. Vet. Rec., 87: 4351.  [Google Scholar]; Rehm and White, 1970 Rehm, W. F. and White, G. 1970. A field trial with trimethoprim and sulphadoxine in bacterial diseases of cattle and pigs. Vet. Rec., 87: 3942.  [Google Scholar]; Craig 1972 Craig, G. R. 1972. The place of potentiated trimethoprim in the therapy of diseases of the skin in dogs and cats. J. small Anim. Pract., 13: 6570.  [Google Scholar]).  相似文献   
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Vision Guided Precision Cultivation   总被引:1,自引:0,他引:1  
Slaughter  D. C.  Chen  P.  Curley  R. G. 《Precision Agriculture》1999,1(2):199-217
A color machine vision based automatic guidance system was developed for precision guidance of an agricultural cultivator. The guidance system was designed to operate in weedy row crop fields at the time of first cultivation. The performance of the system varied from an RMS guidance error of 7 mm under low weed loads to 12 mm under high weed loads and was capable of operating at travel speeds up to 16 km/h.  相似文献   
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This work studied the impacts of variations in environmental temperature on hyperspectral imaging features in the visible and near infrared regions for robust species identification for weed mapping in tomato production. Six major Californian processing tomato cultivars, black nightshade (Solanum nigrum L.) and redroot pigweed (Amaranthus retroflexus L.) were grown under a variety of diurnal temperature ranges simulating conditions common in the Californian springtime planting period and one additional treatment simulating greenhouse growing conditions. The principal change in canopy reflectance with varying temperature occurred in the 480-670 and 720-810 nm regions. The overall classification rate ranged from 62.5% to 91.6% when classifiers trained under single temperatures were applied to plants grown at different temperatures. Eliminating the 480-670 nm region from the classifier’s feature set mitigated the temperature effect by stabilizing the total crop vs. weed classification rate at 86.4% over the temperature ranges. A site-specific recalibration method was also successful in alleviating the bias created by calibrating the models on the extreme temperatures and increased the classification accuracy to 90.3%. A global calibration method, incorporating all four temperature conditions in the classifier feature space, provided the best average total classification accuracy of 92.2% out of the methods studied, and was fairly robust to the varying diurnal temperature conditions.  相似文献   
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