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101.
N DeLapp S Wu R Belagaje E Johnstone S Little H Shannon F Bymaster D Calligaro C Mitch C Whitesitt J Ward M Sheardown A Fink-Jensen L Jeppesen C Thomsen P Sauerberg 《Canadian Metallurgical Quarterly》1998,244(1):156-160
1. Three experiments were conducted to investigate the diurnal variation of blood viscosity in broilers. In experiment 1 food and water were supplied freely at 20 degrees C (20-FW). In experiment 2 food and water were withdrawn at 20 degrees C (20-NFW), while in experiment 3 food and water were withdrawn at 30 degrees C (30-NFW). 2. Blood sampling time points were 09.00 h, 15.00 h, 21.00 h, 03.00 h and 09.00 h the next day in each experiment. 3. In all experiments, whole blood viscosity (WBV), red blood cell count (RBC) and haematocrit (HCT) were greater during the dark (21.00 h and 03.00 h) than during the light period. During the dark period, there were no differences in WBV, RBC and HCT between 20-FW and 20-NFW, or between 20-NFW and 30-NFW. At 09.00 h, WBV and HCT were higher in 20-FW than in 20-NFW. At 15.00 h and 09.00 h (day 2), WBV and HCT were greater in 20-NFW than in 30-NFW. 4. There were no light-dark differences in plasma viscosity (PV), plasma protein concentration (PPC) or mean corpuscular volume (MCV) in any experiment. However, 20-NFW birds had a lower PPC and higher MCV compared with 20-FW, and a higher PPC and lower MCV compared with 30-NFW, while no difference was found in PV. 5. WBV increased linearly with RBC and HCT. PV increased with PPC, while MCV decreased. 6. These results indicate that there is diurnal variation in whole blood viscosity, which is greater during the dark than during the light period. During the light period it is strongly influenced by high environmental temperature and food and water withdrawal. 相似文献
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A spectrophotometric assay was developed for measuring the uptake of the antibiotic actinobolin by hydroxylapatite (HAP) or powdered human enamel. The assay is sufficiently sensitive to detect less than 2.0 mug actinobolin/ml of: 0.01 M sodium phosphate buffer at pH 5.5, 7.0, or 8.0; deionized water; deionized water containing 1% salivary supernatant; or each of the above indicated solvent systems containing 1-5 parts per million sodium fluoride. The utility of the assay system has been demonstrated by date which show that approximately 5-7 mug of actinobolin are bound per 10 mg of HAP or powdered enamel. 相似文献
105.
The thermal degradation of Nafion–H, Nafion–K, and the mixture of each of these with poly(methyl methacrylate) (PMMA) has been studied. A mechanism is proposed for the thermal degradation of Nafion–H that involves an initial cleavage of the carbon–sulfur bond leading to SO2 and OH radical and a carbon-based radical. This carbon-based radical then undergoes further degradation. The addition of PMMA to Nafion–H inhibits further degradation of the Nafion carbon-based radical and instead radical recombination reactions between PMMA fragments and this Nafion radical dominate the reaction scheme. The replacement of the hydrogen in Nafion–H with a potassium (i.e., Nafion–K) produces a much more robust material that does not degrade under conditions similar to those used for Nafion–H. Nafion–K has little effect on the degradation of PMMA. 相似文献
106.
Zahari Zlatev Per Grove Thomsen 《International journal for numerical methods in engineering》1979,14(7):1051-1061
The application of finite element methods to parabolic partial differential equations leads to large linear systems of first-order ordinary differential equations. Very often these systems are stiff and difficulties arise in their numerical solution. We attempt to analyse the problem of how to select numerical methods for the solution of such linear systems. 相似文献
107.
J L Thomsen 《Journal of dairy science》1976,59(2):288-292
Magnesium, potassium, sodium, creatinine and bilirubin concentrations, and osmolality in bovine fetal fluids have been investigated to seek a possible application to the determination of gestation age. Potassium ion concentration during pregnancy decreased in amniotic fluid. Sodium ion concentration and osmolality increased in allantoic fluid during the same period. Creatinine concentration rose throughout pregnancy in both amniotic and allantoic fluids. However, none of these indicators provided a reliable correlation with fetal age as determined by measurements of head circumference. 相似文献
108.
L. Sennerby P. Thomsen L. E. Ericson 《Journal of materials science. Materials in medicine》1993,4(3):240-250
The tissue response to screw-shaped implants of commercially pure titanium was studied by light microscopy 3–180 days after insertion in the rabbit tibia. The implant site in the tibial metaphysis consisted mainly of cortical bone. Three days after implantation, osteoblasts, producing osteoid, were observed at the endosteal surface and elongated mesenchymal cells were present in the injury area. Some macrophages but rather few other inflammatory cells were identified. Multinuclear giant cells were in direct contact with the implant and formed an almost continuous layer along the surface from the 7th day. The number of giant cells decreased with time and with increased bone-titanium contact. Bone formation was never seen direct on the implant surface but was first observed at day 7 as a woven trabecular bone formed at the endosteal surface and extending towards the implant and as a solitary formation of woven bone close to the implant. The solitary bone matrix served as a base for surface osteoblasts which produced osteoid in a lamellar arrangement. With time the two types of newly formed bone fused and more bone filled the threads and became remodelled by bone remodelling units. Light microscopic morphometry in ground sections demonstrated that the bone/titanium contact and bone area in the threads increased with time up to 6 months after implantation 相似文献
109.
JC Nielsen HR Andersen PE Thomsen L Thuesen PT Mortensen T Vesterlund AK Pedersen 《Canadian Metallurgical Quarterly》1998,97(10):987-995
OBJECTIVE: In the present study, physical and sexual abuse among incarcerated youth were examined with respect to sexual activity, contraceptive use, and pregnancy. METHOD: The self-report survey data were collected from 62 females and 334 males who were incarcerated in Nevada youth correctional facilities in the summer of 1994. Of the males, 46.8% (n = 156) reported a history of physical abuse and 9.9% (n = 33) reported sexual abuse. A surprisingly high 73% (n = 46) of the females reported a history of physical abuse and 68.3% (n = 43) reported sexual abuse. RESULTS: The analyses indicated that females who reported a history of sexual abuse had an earlier mean age of first intercourse than those who reported no sexual abuse. In addition, male and female respondents with a history of physical and/or sexual abuse reported using no method of contraception as compared to youth with no history of abuse. CONCLUSIONS: Implications of these results for detention-based counseling and prevention programming are discussed. 相似文献
110.