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41.
JJ Callaghan EE Forest JP Olejniczak DD Goetz RC Johnston 《Canadian Metallurgical Quarterly》1998,80(5):704-714
We evaluated the results twenty to twenty-five years after ninety-three consecutive, nonselected Charnley total hip arthroplasties performed with cement by the senior one of us in sixty-nine patients who were less than fifty years old at the time of the procedure. Seventy of the seventy-two hips in the living patients were followed radiographically for at least twenty years. Twenty-seven hips (29 per cent) had a revision or a resection of the prosthesis during the follow-up period. The revision or the resection was performed because of aseptic loosening in twenty-one hips (23 per cent), infection in four (4 per cent), dislocation in one (1 per cent), and fracture of the femur in one. Eighteen acetabular components (19 per cent) and five femoral components (5 per cent) were revised because of aseptic loosening, and an additional fourteen acetabular components (15 per cent) and seven femoral components (8 per cent) demonstrated definite or probable radiographic loosening. The present study demonstrates the long-term durability of total hip arthroplasty performed with cement in an active population of patients. The fixation of the femoral component was found to perform better than that of the acetabular component at twenty to twenty-five years after the procedure. 相似文献
42.
LK Malendowicz C Macchi GG Nussdorfer A Markowska 《Canadian Metallurgical Quarterly》1996,11(3):641-645
The effects of a prolonged administration of bradykinin (BK) and/or D-Arg, [Hyp3, D-Phe7]-BK, a specific antagonist of BK receptors (BK-A) (daily subcutaneous injections of 4 nmol/rat for 6 days) on the function of the pituitary-adrenocortical axis were investigated. BK did not change plasma aldosterone concentration (PAC), but markedly lowered that of corticosterone (PBC) and consequently induced a compensatory hypersecretion of ACTH by the pituitary gland. BK-A did not apparently affect the function and growth of the adrenal gland, but, when administered together with BK, markedly raised both PAC and PBC, and provoked a significant atrophy of the adrenal gland, probably due to loss of parenchymal cells. Taken together, these rather puzzling findings do not appear to provide clear evidence for the involvement of BK in the physiological regulation of adrenocortical growth and steroidogenic capacity in rats. 相似文献
43.
AV Susekov MG Tvorogova GG Arabidze VV Kukharchuk 《Canadian Metallurgical Quarterly》1998,70(9):57-61
AIM: The study of the hypolipidemic efficiency, safety and tolerance of ciprofibrate (lipanor) in therapy of atherogenic hyperlipoproteinemia. MATERIALS AND METHODS: The trial included 14 hypertensive postmenopausal females, 14 patients with diabetes mellitus type II, 14 males with coronary heart disease and primary hyperlipoproteinemia (total cholesterol > 6.5 mmol/l, triglycerides < 4.5 mmol/l under low-cholesterol diet). Lipanor was given for 12 weeks in a daily single dose 100 mg in the morning. Lipids and other biochemical indices were measured in a fasting state after 1 and 3 months of lipanor treatment. RESULTS: After 1 month of lipanor treatment there was a 22-30%, 24-49% decrease in the level of low-density lipoprotein cholesterol, triglycerides, respectively. High-density lipoprotein cholesterol increased by 16%. The hypolipidemic effect of lipanor persisted for 3 months during which triglycerides continued to fall (up to 38.5%). Lipanor was well tolerated, only one patient with diabetes mellitus had hyperactivity of creatine phosphokinase manifesting with clinical symptoms (the drug was discontinued). 3 patients developed mild side effects. Alkaline phosphatase activity inhibited in all the groups by 25-41%. CONCLUSION: Lipanor is a highly effective, safe hypolipidemic drug with good tolerance. It can be recommended for correction of atherogenic hyperlipoproteinemia in patients at high risk of atherosclerosis progression. 相似文献
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45.
Phenylbutazone was administered intravenously (i.v.) to a group of four lactating cows at a dosage of 6 mg/kg body weight. Whole plasma, protein-free plasma and milk were analysed for phenylbutazone residues. Pharmacokinetic parameters of total and free phenylbutazone in plasma were calculated using a non compartmental method. In regards to whole plasma data, the mean volume of distribution at steady state (Vss), was 147 mL/kg body weight, with a mean (+/-SEM) terminal elimination half-life (t1/2) of 40+/-6 h. The mean clearance (Cl) was 3 mL/h/kg body weight. The Vss as determined from the protein-free plasma fraction was 50021 mL/kg body weight. This larger Vss of free phenylbutazone compared to total plasma phenylbutazone was attributed to a high degree of plasma protein binding, as well as the greater penetration of free phenylbutazone into tissues. The mean t1/2 of free phenylbutazone was 39+/-5 h. This similarity to the t1/2 estimated from total plasma phenylbutazone data is attributed to an equilibrium between free and plasma phenylbutazone during the terminal elimination phase. Mean t1/2 as determined from milk, applying a urinary excretion rate model, was 47+/-4 h. Milk clearance of phenylbutazone was 0.009 mL/h/kg body weight, or about 0.34% of total body clearance. Furthermore, evidence suggests that phenylbutazone either binds to milk proteins, or is actively transported into milk, as its concentration in milk was greater than that predicted due to a simple partitioning from plasma into milk. 相似文献
46.
J De Meester GG Persijn T Wujciak G Opelz Y Vanrenterghem 《Canadian Metallurgical Quarterly》1998,66(9):1154-1159
BACKGROUND: Upon the availability of a cadaveric donor kidney, a delicate allocation process precedes every transplantation. A remodeled Eurotransplant Kidney Allocation System (ETKAS)-derived from simulation studies-was installed in March 1996. The purpose was to adjust long waiting times and international exchange balances, while aiming at an optimal HLA-mismatch distribution. The new ETKAS consisted of a point-score system that was 100% patient oriented. METHODS: The impact of the new ETKAS on the composition of the waiting list, and the outcome of the allocation procedures during its first year, were evaluated and compared with the results obtained in 1995. RESULTS: The percentage of long-waiting patients and of patients with poorly matchable HLA phenotype increased significantly, from 9% to 19% and from 19% to 29%, respectively. Zero HLA-A-, HLA-B-, HLA-DR-mismatched patients still comprised 23% of the kidney transplant activity. The kidney exchange of the different Eurotransplant countries became balanced within 4 months; this persisted during the rest of the year. Pediatric patients had a high transplantation rate due to an assignment of extra points. The composition of the waiting list showed, after 1 year, fewer long-waiting patients and fewer patients with rare HLA phenotypes. CONCLUSIONS: The new ETKAS was able in its first year to meet the goals set at its introduction. In comparison with the old ETKAS, there was a better trade-off between HLA matching and waiting time. The value of computer simulation studies has been demonstrated impressively in the context of organ allocation. 相似文献
47.
48.
Robert A. Moreau David B. Johnston Kevin B. Hicks 《Journal of the American Oil Chemists' Society》2007,84(11):1039-1044
All commercial corn oil is obtained by pressing corn germ and/or extracting the germ with hexane. In the current study, six
types of corn oil were prepared by extracting corn germ, corn fiber and ground corn, each with hexane or with ethanol. The
levels of lutein, zeaxanthin and other carotenoids were quantitatively analyzed in the six corn oils. The levels of lutein + zeaxanthin
in the oil ranged from 2.3 μg/g for hexane-extracted corn germ oil to 220.9 μg/g for ethanol-extracted ground corn oil. These
results indicate that a diet that includes 30 g (~2 tbsp) per day of the unrefined corn oil obtained by extracting ground
corn with ethanol would provide ~6 mg of lutein + zeaxanthin, the daily dosage that is currently considered to be necessary
to slow the progression of age-related macular degeneration.
Mention of trade names or commercial products in this publication is solely for the purpose of providing specific information
and does not imply recommendation or endorsement by the U.S. Department of Agriculture. 相似文献
49.
50.
Reactive Laser Ablation Synthesis of Nanosize Alumina Powder 总被引:1,自引:0,他引:1
Gregory P. Johnston Ross Muenchausen Douglas M. Smith William Fahrenholtz Steve Foltyn 《Journal of the American Ceramic Society》1992,75(12):3293-3298
An aluminum (Al) target was laser ablated in an oxygen (O2 ) atmosphere, producing nanosize alumina (Al2 O3 ) powder. The powder surface area decreased (and the particle size increased) with both increasing oxygen pressure and laser fluence. All powders produced had surface areas between 135 and 250 m2 /g, corresponding to primary particle sizes ranging from 7 to 3 nm in radius. Phase evolution with temperature was studied via X-ray diffraction. These powders showed a direct transformation from γ- to α-alumina at approximately 1200°C, bypassing other transition alumina phases, while still maintaining small particle size ( 30 nm). Despite the nanosize particles, green densities equal to 54% of the skeletal density (i.e., true density of the solid phase) were obtained by uniaxial pressing at 40 MPa. 相似文献