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11.
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
12.
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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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
15.
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
16.
Twenty-five steers of each of three breedtypes (Angus, Brahman and F(1) Brahman x Angus) were sorted by frame size and muscle thickness, assigned to groups (five steers of each breedtype) to be fed for 0, 56, 112, 168 or 224 days, slaughtered and compared for various carcass traits. Steers of each breedtype had similar dressing percentages. Carcasses from all three breedtypes merited similar USDA quality and yield grades; breedtypes differences in quality grade were slight. Differences were found in the fat deposition patterns exhibited by the three breedtypes. Brahman steers tended to deposit more of their total fat as subcutaneous fat early in the feeding period. Angus steers had more (P < 0·05) seam fat as a percentage of carcass weight at all five feeding periods and more (P < 0·05) kidney, pelvic and heart fat at two of the five feeding periods than Brahman steers. Brahman steers had a higher percentage of their separable lean in the muscles of the round than did steers of the other breedtypes. 相似文献
17.
The morphology and impact properties of polystyrene-maleic anhydride/bromobutyl rubber blends have been studied as a function of interfacial modification and melt processing conditions. It is found that dimethylaminoethanol (DMAE) serves as a reactive compatibilizing agent for these blends and that the addition of DMAE results in a five-fold reduction In the size of the dispersed phase. Evidence for covalent bond formation between the DMAE and the elastomer and reactive polystyrene phases is presented. The volume average diameter of the minor phase increases significantly as the screw rotation speed and the material throughput increase. In fact, control of various material and processing parameters can be used to effectively control the particle size distribution during compounding. Impact strength measurements are shown to be clearly dependent on the quantity of DMAE in the system as well as the concentration of elastomer. Saturation of the interface with DMAE is shown to be an important consideration. 相似文献
18.
A mixed helix--beta-sheet model of the transmembrane region of the nicotinic acetylcholine receptor 总被引:2,自引:0,他引:2
We have modelled the transmembrane region of the 7 nicotinicacetylcholine receptor as a mixed -helical/ß-sheetstructure. The model was mainly based on the crystal structureof a pore-forming toxin, heat-labile enterotoxin. This is apentameric protein having a central pore or channel composedof five -helices, one from each of the 5 B subunits that formthis pentamer. The remainder of this structure is ß-sheet,loops and a short -helix, not included in the model. The modeluses this channel as a template to build the transmembrane region,from M1 to the middle of M3. The remainder of M3 and M4 werebuilt de novo as -helices. Great consideration was given tolabelling data available for the transmembrane region. In generalterms, the shape of the model agrees very well with that obtainedindependently by electron microscopic analysis and the secondarystructure predicted by the model is in accord with that estimatedindependently by Fourier transform infrared spectroscopy. TheM2 helical region of the model is only slightly kinked, contraryto what is inferred from electron microscopic analysis, buthas the same overall shape and form. On the membrane face ofthe model, the presence of deep pockets may provide the structuralbasis for the distinction between annular and non-annular lipidbinding sites. Also, the transmembrane region is clearly asymmetricin the direction perpendicular to the membrane, and this mayhave strong influence on the surrounding lipid composition ofeach leaflet of the cytoplasmic membrane. 相似文献
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20.
GG Stone MM Chengappa RD Oberst NH Gabbert S McVey KJ Hennessy M Muenzenberger J Staats 《Canadian Metallurgical Quarterly》1993,5(3):378-385
The polymerase chain reaction was employed to correlate Salmonella serovars isolated from fecal material of greyhounds suffering from gastroenteritis with those isolated from the diet fed to the greyhounds prior to onset of diarrhea. Kennels around the Abilene, Kansas, area were contacted and supplied with materials needed to collect a portion of the diet each day. With the onset of diarrhea, the kennels were instructed to ship the fecal material and diet from the previous 10 days to the laboratory for testing. Forty-one fecal samples and corresponding diets were screened for Salmonella, Clostridium perfringens, Campylobacter jejuni, Staphylococcus aureus, Staphylococcus intermedius, and pathogenic (piliated) Escherichia coli by direct culture using standard procedures. The fecal material was also screened for coronavirus and parvovirus using electron microscopy. Thirty-five "normal" fecal samples were screened for all of the above mentioned microorganisms as a control. In addition, the fecal material was screened for E. coli verotoxins I and II and clostridial enterotoxins. A total of 61 Salmonella isolates were recovered from the 41 samples of feces and diet submitted for testing; 31 were recovered from the feces and 30 from the diet. Four Salmonella isolates were recovered from the normal fecal samples. Results obtained by PCR, plasmid profiles, antigenic analysis, and antibiogram profiles indicated that 16 of the 31 isolates recovered from the fecal material were the same strain as that recovered from the diet. 相似文献