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41.
42.
The mandibular gland secretions of the ponerine ants Odontomachus hastatus, O. clarus, and O. brunneus contain alkylpyrazines. These compounds, 2,5-dimethyl-3-isopentylpyrazine in O. hastatus and O. clarus, and 2,6-dimethyl-3-pentyl-, -butyl-, -propyl-, and -ethyl-pyrazines in O. brunneus, have previously not been found as animal natural products. These compounds function as powerful releasers of alarm behavior for Odontomachus workers and are probably also utilized as defensive compounds. 相似文献
43.
Due to the discrepancy in metabolic sodium (Na) requirements between plants and animals, cycling of Na between humans and plants is limited and critical to the proper functioning of bio-regenerative life support systems, being considered for long-term human habitats in space (e.g., Martian bases). This study was conducted to determine the effects of limited potassium (K) on growth, Na uptake, photosynthesis, ionic partitioning, and water relations of red-beet (Beta vulgaris L. ssp. vulgaris) under moderate Na-saline conditions. Two cultivars, Klein Bol, and Ruby Queen were grown for 42 days in a growth chamber using a re-circulating nutrient film technique where the supplied K levels were 5.0, 1.25, 0.25, and 0.10 mM in a modified half-strength Hoagland solution salinized with 50 mM NaCl. Reducing K levels from 5.0 to 0.10 mM quadrupled the Na uptake, and lamina Na levels reached -20 g kg-1 dwt. Lamina K levels decreased from -60 g kg-1 dwt at 5.0 mM K to -4.0 g kg-1 dwt at 0.10 mM K. Ruby Queen and Klein Bol responded differently to these changes in Na and K status. Klein Bol showed a linear decline in dry matter production with a decrease in available K, whereas for cv. Ruby Queen, growth was stimulated at 1.25 mM K and relatively insensitive to a further decreases of K down to 0.10 mM. Leaf glycinebetaine levels showed no significant response to the changing K treatments. Leaf relative water content and osmotic potential were significantly higher for both cultivars at low-K treatments. Leaf chlorophyll levels were significantly decreased at low-K treatments, but leaf photosynthetic rates showed no significant difference. No substantial changes were observed in the total cation concentration of plant tissues despite major shifts in the relative Na and K uptake at various K levels. Sodium accounted for 90% of the total cation uptake at the low K levels, and thus Na was likely replacing K in osmotic functions without negatively affecting the plant water status, or growth. Our results also suggest that cv. Ruby Queen can tolerate a much higher Na tissue concentration than cv. Klein Bol before there is any growth reduction. Grant numbers: 12180. 相似文献
44.
Anterior uveal melanoma, with secondary keratitis, cataract, and glaucoma, in a horse. 总被引:1,自引:0,他引:1
H J Davidson G L Blanchard C A Wheeler J A Render 《Journal of the American Veterinary Medical Association》1991,199(8):1049-1050
Intraocular melanoma was diagnosed in a 13-year-old horse. Secondary clinical findings included keratitis, cataract, and glaucoma. The eye was enucleated. Follow-up information did not give an indication of metastatic disease. 相似文献
45.
Pheochromocytoma in the dog 总被引:1,自引:0,他引:1
D C Twedt S L Wheeler 《Veterinary Clinics of North America: Small Animal Practice》1984,14(4):767-782
46.
Wheeler WH 《Science (New York, N.Y.)》1960,131(3408):1171-1176
47.
48.
Two infectious bursal disease viruses (IBDVs)--a cell-culture-adapted chicken strain designated Edgar strain and a recent isolate from turkeys in Missouri--were used to assay sera from 10 Iowa turkey flocks collected between 1 and 16 weeks of age. The two viruses were serologically distinct in cross-neutralization tests. For all flocks, a similar serologic pattern was found consisting of (1) low maternal antibody titers to turkey IBDV and occasionally to Edgar strain IBDV between 1 and 3 weeks of age, (2) a period of very low or no detectable titers between 3 and 7 weeks of age, and (3) sharply rising high titers to turkey IBDV with low titers to Edgar IBDV beginning at 5 to 8 weeks of age. These findings indicate that infection with IBDV of the serotype represented in this study by the turkey isolate is common in Iowa turkey flocks, whereas infection with IBDV represented by Edgar strain is uncommon. Infection occurred between 3 and 7 weeks of age during the late brooding period or after birds had been moved to an intermediate growing facility. All flocks developed complicated respiratory disease with excessive mortality caused by Escherichia coli septicemia, typically between 3 and 6 weeks of age. Although there was a temporal relationship between IBDV infection and respiratory disease, the possible role of IBDV in the process is unknown. 相似文献
49.
50.
White SN Casas E Wheeler TL Shackelford SD Koohmaraie M Riley DG Chase CC Johnson DD Keele JW Smith TP 《Journal of animal science》2005,83(9):2001-2008
The three objectives of this study were to 1) test for the existence of beef tenderness markers in the CAPN1 gene segregating in Brahman cattle; 2) test existing CAPN1 tenderness markers in indicus-influenced crossbred cattle; and 3) produce a revised marker system for use in cattle of all subspecies backgrounds. Previously, two SNP in the CAPN1 gene have been described that could be used to guide selection in Bos taurus cattle (designated Markers 316 and 530), but neither marker segregates at high frequency in Brahman cattle. In this study, we examined three additional SNP in CAPN1 to determine whether variation in this gene could be associated with tenderness in a large, multisire American Brahman population. One marker (termed 4751) was associated with shear force on postmortem d 7 (P < 0.01), 14 (P = 0.015), and 21 (P < 0.001) in this population, demonstrating that genetic variation important for tenderness segregates in Bos indicus cattle at or near CAPN1. Marker 4751 also was associated with shear force (P < 0.01) in the same large, multisire population of cattle of strictly Bos taurus descent that was used to develop the previously reported SNP (referred to as the Germplasm Evaluation [GPE] Cycle 7 population), indicating the possibility that one marker could have wide applicability in cattle of all subspecies backgrounds. To test this hypothesis, Marker 4751 was tested in a third large, multisire cattle population of crossbred subspecies descent (including sire breeds of Brangus, Beefmaster, Bonsmara, Romosinuano, Hereford, and Angus referred to as the GPE Cycle 8 population). The highly significant association of Marker 4751 with shear force in this population (P < 0.001) confirms the usefulness of Marker 4751 in cattle of all subspecies backgrounds, including Bos taurus, Bos indicus, and crossbred descent. This wide applicability adds substantial value over previously released Markers 316 and 530. However, Marker 316, which had previously been shown to be associated with tenderness in the GPE Cycle 7 population, also was highly associated with shear force in the GPE Cycle 8 animals (P < 0.001). Thus, Marker 316 may continue to be useful in a variety of populations with a high percentage of Bos taurus backgrounds. An optimal marker strategy for CAPN1 in many cases will be to use both Markers 316 and 4751. 相似文献