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141.
Effect of recombinant cytokines on leucocytes and physiological changes in bovine mammary glands during early involution 总被引:2,自引:0,他引:2
Wedlock DN McCarthy AR Doolin EE Lacy-Hulbert SJ Woolford MW Buddle BM 《The Journal of dairy research》2004,71(2):154-161
We examined the effects of administering recombinant bovine cytokines to non-lactating dairy cows and measured mammary gland leucocytes and the involution process. After the final milking, groups of cows were given an intramammary infusion of cytokine in two quarters. These cytokines were recombinant bovine interleukin-2 (rbolL-2) (2 x 10(5) units, n = 6), recombinant bovine granulocyte-macrophage colony stimulating factor (rboGM-CSF) (500 microg, n = 4) and recombinant bovine interleukin-1beta (rbolL-1beta) (10 microg, n = 10). Each animal also received an infusion of phosphate-buffered saline (PBS) in the other two quarters as controls. The rbolL-2 and rboGM-CSF were produced in a yeast expression system, while rbolL-1beta was produced in Escherichia coli. Leucocyte numbers, bactericidal activity of leucocytes, and concentrations of citrate and lactoferrin in quarter secretion samples were monitored after infusion of cytokine or PBS. Infusion of rbolL-2 had minimal effect on leucocyte numbers and concentrations of citrate and lactoferrin. Both rboGM-CSF and rbolL-1beta induced a rapid increase in the number of neutrophils and macrophages compared with control PBS quarters. Concentrations of lactoferrin in secretions were increased by rboGM-CSF and rbolL-1beta compared with control PBS quarters. In addition, infusion of glands with rbolL-1beta lowered the citrate:lactoferrin molar ratio compared with PBS control quarters. The results indicate that intramammary infusion of either rboGM-CSF or rbolL-1beta at cessation of milking immediately increased the number of phagocytic cells in the gland. These cytokines, in particular rbolL-1beta, also increased the rate of mammary gland involution during the early dry period. 相似文献
142.
de Peralta Menendez RG Murray MM Andino SL 《IEEE transactions on bio-medical engineering》2004,51(9):1680-1683
This paper proposes a new strategy for improving the localization capabilities of linear inverse solutions, based on the relationship between the real solution and the estimated solution as described by the resolution matrix equation. Specifically, we present two alternatives based on either the partial or total inversion of the resolution matrix and applied them to the minimum norm solution, which is known for its poor performance in three-dimensional (3-D) localization problems. The minimum norm transformed inverse showed a clear improvement in 3-D localization. The strong dependence of localization errors with the eccentricity of the sources, characteristic of this solution, disappears after the proposed transformation. A similar effect is illustrated, using a realistic example where multiple generators at striate areas are active. While the original minimum norm incorrectly places the generators at extrastriate cortex, the transformed minimum norm localizes, for the example considered, the sources at their correct eccentricity with very low spatial blurring. 相似文献
143.
The direct combination of gel electrophoresis and infrared laser desorption/ionization time-of-flight mass spectrometry has been demonstrated. We present results for infrared laser desorption and ionization mass spectrometry of peptides and proteins directly from a polyacrylamide gel without the addition of a matrix. Analyte molecules up to 6 kDa were ionized directly from a vacuum-dried sodium dodecyl sulfate-polyacrylamide gel after electrophoretic separation. Mass spectra were obtained at the wavelength of 2.94 microm, which is consistent with IR absorption by N-H and O-H stretch vibrations of water and other constituents of the gel. A 5-nmol quantity of peptide or protein was loaded per gel slot, although it was possible to obtain mass spectra from a small fraction of the gel spot. This technique shows promise for the direct identification of both parent and fragment masses of proteins contained in polyacrylamide gels. 相似文献
144.
145.
Experiments on d.c. electrical conduction in thin films of r.f. reactively sputtered zinc sulphide (thicknesses from 100 to 1000 Å) sandwiched between Al and Au are described. For an electric field between 105 and 106 V cm-1, the plot of log J versus √V is linear; the thermal evolution of the current is described by log J ~T-1/3. It is therefore assumed that the electrical conduction is due to the emission of electrons from defects into the conduction band of the zinc sulphide. 相似文献
146.
PR Murray 《Canadian Metallurgical Quarterly》1978,8(6):708-714
The quantitative growth, the colony size, and the rate of growth of 47 clinical anaerobic isolates were compared on five different media, namely Brucella agar, brain heart infusion agar, Columbia agar, Schaedler agar, and tryptic soy agar. There was no significant difference in the quantitative growth of the anaerobes inoculated onto the five media. Although no single medium was superior for the growth of all isolates, 12 of 22 isolates, inoculated onto media stored for 4 weeks or less, grew best on Schaedler agar. The effects of supplementation of the media with reducing agents and reduction of the media before use were also analyzed and were found to be affected by the composition and length of storage of the media, as well as the bacteria tested. 相似文献
147.
Used cold water stimulation to measure pain in the hands and feet of 10 sinistral and 10 dextral female undergraduates. After an adaptation trial the S placed her foot (hand) in water of 2.C, and threshold and tolerance levels were recorded. A total of 20 trials, 5 with each hand and foot, were administered with each S. Greater sensitivity and pain tolerance were obtained in the left hand and foot of both sinistral and dextral Ss, and sinistral Ss were less sensitivve than dextral. Results support an interpretation involving bilateral assymmetry of the brain more than one involving hand and foot calluses. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
148.
Weckler Nora; Wollersheim Janet P.; Goggin Judith P.; Dunham Frances Y.; Ferraro Douglas P.; White Kathleen M.; Benimoff Murray; Pate James L. 《Canadian Metallurgical Quarterly》1982,37(12):1380
Reports for 1982 are listed for the following regional association meetings: Sixty-Second Annual Meeting of the Western Psychological Association; Fifty-Second Annual Meeting of the Rocky Mountain Psychological Association; Fifty-Fourth Annual Meeting of the Midwestern Psychological Association; Twenty-Eighth Annual Meeting of the Southeastern Psychological Association; Twenty-Eighth Annual Meeting of the Southwestern Psychological Association; Twenty-Second Annual Meeting of the New England Psychological Association; Fifty-Third Annual Meeting of the Eastern Psychological Association; and Seventy-Fourth Annual Meeting of the Southern Society for Philosophy and Psychology. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
149.
Conducted an experiment with 48 female adrenalectomized Sprague-Dawley rats, who were injected daily with aldosterone (.25 mg/kg) or deoxycorticosterone (3 mg/kg) in combination with corticosterone. The mineralocorticoids increased food intake and weight gain well beyond that of controls receiving only corticosterone injections. The weight gain was not wholly dependent on increased food intake, as separate groups of Ss maintained on a restricted diet (10 g of laboratory chow/day) also displayed significant mineralocorticoid-stimulated weight gain. Although carcass composition was not directly determined, the undifferentiated wet/dry tissue ratios, hematocrit values, and nasoanal lengths found across groups suggested that the observed effect of mineralocorticoids was on body fat. Aldosterone and deoxycorticosterone can have important actions on energy metabolism as well as on sodium regulation. (9 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
150.
Continuous cultures of Saccharomyces cerevisiae show a robust autonomous temperature compensated oscillation in many metabolic functions. Respiratory activity, a convenient output to measure, oscillates with a period of 40 min. Deletion of GTS1, whose protein product has homology to the circadian per protein, has been implicated in temporal events within yeast, causes a reduction in periodicity to 18 min (wild-type period 40-60 min). The dilution rate was steadily increased from 0.04/h to 0.085/h and the oscillation stabilized after four to six dilutions. However, Gts1p's involvement in the maintenance and generation of metabolic synchrony, and in the central oscillating loop, appear to be minimal, as the mutant oscillation was robust and autonomous. Deletion of GTS1 did cause decreased temperature compensation of the period of the oscillation from Q(10) = 1.07 for the wild-type to Q(10) = 1.6 for the mutant. Also the degree of nutrient compensation observed for the wild-type was not observed in the GTS1-null mutant strain. It is postulated that Gts1p is involved in the mechanism that communicates external conditions, such as temperature, to the central oscillating loop. 相似文献