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961.
Fulmer R Loeb WF Martin DP Gard EA 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1984,13(1):19-25
The intravenous administration of 0.75 gm glucose per kg and the measurement of serum glucose pretest and at 10, 20, 30, 60, 90 and 120 minutes constitute a satisfactory protocol for intravenous glucose tolerance testing of Rhesus (Macaca mulatto) and African Green (Cercopithecus aethiops) monkeys. No significant differences were noted between animals restrained with ketamine hydrochloride and those restrained with sodium pentobarbital, but the African Green males and females and the male Rhesus monkeys yielded significantly different results while being manually restrained. 相似文献
962.
Hirsch VM Mitcham SC Dunn DK 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1984,13(2):16-20
An unusual combination of blood cytopenias and monocytic proliferation was observed in a dog. Initial hematologic findings included severe thrombocytopenia, neutropenia, mild nonregenerative anemia and apparently normal bone marrow. Subsequently, a severe persistent monocytosis developed and the bone marrow became populated with monocytes and cytophagic macrophages. Splenomegaly was due to reticuloendothelial hyperplasia and extramedultary hematopoiesis. Treatment consisted of splenectomy and azathioprine but the response was poor and the dog was euthanized. Postmortem examination revealed a hypocellular bone marrow which contained moderate numbers of monocytes and plasma cells. Neoplastic proliferation was absent in visceral organs. No definite diagnosis was established; chronic blood cell consumption, perhaps immune-mediated, may have been responsible for the extensive reticuloendothelial hyperplasia and cytophagia. 相似文献
963.
Factors affecting somatic cell counts and the association between somatic cell counts and milk production were evaluated. Data were collected from 748 Ontario Dairy Herd Improvement Corporation supervised herds that were on production and somatic cell count programs between April 1981 and March 1983. Two data files were created; one, the lactation summary file, contained one record per cow on each of 9406 Holsteins and the other, the test day file, included results of all tests during the complete lactation on each of the above cows. The latter file contained 85,236 records. Multiple curvilinear least squares regression was used to create five separate models. The dependent variables used in the models were natural logarithms (Loge) of the geometric mean of the somatic cell count for the lactation, 305 day milk production and breed class average for milk from the lactation summary file, and loge of the 24 hour somatic cell count and 24 hour milk production from the test day file. The somatic cell count at both the lactation and test day level increased with age up to approximately ten years and thereafter slowly decreased. The variable "days in milk" was not significantly associated with the lactation average somatic cell count. A curvilinear relationship was found between days in lactation at the time of test and the somatic cell count of 24 hour milk production. The somatic cell count increased until approximately 250 days in lactation and thereafter slowly decreased. It was found that the highest cell counts occurred in summer and the lowest in winter.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
964.
Bird SJ 《Science (New York, N.Y.)》1984,224(4649):595-596
965.
Mahoney MS 《Science (New York, N.Y.)》1984,226(4670):39-40
966.
Up to 60 percent of the total marine primary production (or about one-fourth of the total global carbon dioxide fixation) passes through the free-living bacterioplankton. Grazing by bacteriovores is probably the predominant fate of the bacteria, although data are scarce. Evidence is presented that previously uncharacterized, small eukaryotes that are able to pass even 0.6-micrometer filters may be responsible for a large fraction (more than 50 percent) of the total grazing in coastal waters. These organisms have not yet been observed microscopically. 相似文献
967.
Effects of pretreatment solutions containing varying concentrations of calcium, potassium, ammonium and nitrate were evaluated by measuring fluxes of the same ions during a subsequent 4-hour uptake by Douglas-fir seedlings. Maximal rate of ammonium uptake (11 microeq g(-1) root dry weight h(-1)) was about 5 times faster than that of nitrate (2 microeq g(-1) root dry weight h(-1)). Ammonium uptake was most rapid after pretreatment with low potassium levels and was unaffected by ammonium pretreatment. Nitrate uptake was most rapid after pretreatment with high levels of nitrate and low levels of potassium. Calcium uptake was greater when nitrate replaced ammonium as the N source. High calcium pretreatment levels depressed subsequent calcium uptake or resulted in calcium release in both ammonium and nitrate experiments. Potassium efflux occurred with both N sources, but the release was less during nitrate uptake than during ammonium uptake. Efflux of potassium is probably associated with the high potassium status of the seedlings and the exchange between potassium and other cations. High levels of potassium in the pretreatment solutions enhanced potassium efflux and caused a reduction in the subsequent rates of uptake of both ammonium and nitrate. Length of pretreatment and seedling size generally did not affect uptake rates. 相似文献
968.
B C Flann B A Lodge 《Journal of the Association of Official Analytical Chemists》1986,69(6):1026-1030
The validation of a liquid chromatographic procedure suitable for the determination of calcitriol and alfacalcidol in their respective formulations labeled to contain at least 0.25 micrograms drug per unit is described. The capsule content is diluted and chromatographed in 15-20 min on silica columns (5 micron) with a mobile phase of hexane-tetrahydrofuran-methylene dichloride-isopropanol (72 + 12 + 12 + 4, v/v) with detection at 254 nm. The calibration curve is linear. Recoveries of "spikes" averaged 101% with a standard deviation of 2%. Precision was better than 1.5%. 相似文献
969.
970.
Alexandrov YN Crymov AA Kotelnikov VA Petrov GM Rzhiga ON Sidorenko AI Sinilo VP Zakharov AI Akim EL Basilevski AT Kadnichanski SA Tjuflin YS 《Science (New York, N.Y.)》1986,231(4743):1271-1273
From October 1983 to July 1984, the north hemisphere of Venus, from latitude 30 degrees to latitude 90 degrees , was mapped by means of the radar imagers and altimeters of the spacecraft Venera 15 and Venera 16. This report presents the results of the radar mapping of the Maxwell Montes region, one of the most interesting features of Venus' surface. A radar mosaic map and contour map have been compiled. 相似文献