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51.
Peter R. Ellis Victoria J. Burley Anthony R. Leeds David B. Peterson† 《Journal of human nutrition and dietetics》1988,1(2):77-84
We have developed a guar wholemeal bread and tested its physiological efficacy and sensory qualities. The objective of the study was to estimate the optimum concentration of guar in bread required to reduce postprandial glycaemia and insulinaemia without adversely affecting the quality of the bread. Following overnight fasts, 15 normal weight, non-diabetic subjects consumed meals of wholemeal bread alone (controls) and supplemented with guar at three different concentrations (5, 10 and 15% replacement of wheat flour). Blood samples for glucose and insulin analysis were taken preprandially, and at 30 and 60 min after the start of each meal. The acceptability of the wholemeal control and guar breads was assessed using a hedonic scaling method. A significantly lower blood glucose rise at 30 min was found after the 15% guar bread meal compared to the control. Plasma insulin responses at 30 and 60 min were significantly lower after the 10 and 15% guar bread meals compared to the controls. Hedonic scores indicated that the subjects found the 5 and 10% guar breads acceptable and in the case of the 5% variety the mean score was identical to the control. We suggest that a guar concentration of between 5 and 10% replacement of wheat flour (wholemeal or white) should be used for the baking of guar wholemeal bread but further work is needed to define the precise quantity of guar required. 相似文献
52.
53.
Walter G. Sannita Luisa Lopez Lino Maggi Guido Rosadini 《Documenta ophthalmologica. Advances in ophthalmology》1988,70(1):89-96
L-acetylcarnitine is a compound with cholinergic properties and putative action on the visual system and the glucose metabolism. Ten healthy, emmertropic volunteers (age range: 21 to 28 years) were studied. Each subject was administered 5, 10, and 30 mg/kg acute intravenous doses of L-acetylcarnitine and matching placebo. Retinal oscillatory potentials to full-field flash stimulation were recorded before and 30, 60, and 120 min after administration. A systematic reduction of the implicit time of the P2 and N2 oscillatory potential components was observed after administration of the 10 and 30 mg/kg doses: significant changes were not evident at the 5 mg dose or after placebo. The latency reduction was significantly correlated with the postdrug increment of the L-acetylcarnitine plasma concentration. No other systematic modification in latency of amplitude was observed.The results were presented in part at the XXV I.S.C.E.V. Symposium, Sarasota (Florida), April 26–30, 1987. 相似文献
54.
The pharmacokinetics and haemodynamic effects of isosorbide dinitrate (ISDN) have been investigated following administration of single doses as a sublingual (SL) spray (2.5 mg), sublingual tablet (5 mg) and peroral tablet (10 mg) in a randomised, placebo-controlled double-blind cross-over trial in 16 healthy volunteers.After the sublingual spray Cmax was higher (39.0 ng·ml-1) and tmax was shorter (3.9 min) than after the sublingual (22.8 ng·ml-1 and 13.8 min) and peroral (16.9 ng·ml-1 and 25.6 min) tablets. The AUC of ISDN did not differ following any of the three formulations (1031; 879; 997 ng·ml-1·min, for the spray, SL tablet and PO-tablet, respectively). Mononitrate metabolites of ISDN (IS-2-MN and IS-5-MN) and total nitrates in plasma increased in proportion to the administered dose. This indicates that the fraction of the dose absorbed was the same for all the formulations but that the extent of first-pass metabolism increased in the order sublingual spray < sublingual tablet < peroral tablet. Thus, compared to the spray, the relative bioavailability of ISDN was 48% and 28% from the sublingual and peroral tablets, respectively.The haemodynamic effects were quantified using the a/b ratio of the finger pulse wave and the systolic blood pressure and heart rate under orthostatic conditions. For the a/b ratio of the finger pulse, the maximal effect was higher (emax=130%) and the time to emax (temax) shorter (16.6 min) after the spray than the sublingual tablet (84.4% and 25.5 min) or peroral tablet (90.2 and 31.3 min). The onset of effect was within 3, 5 and 7.5 min after the spray, sublingual and peroral tablets, respectively. A larger change in the orthostatically-induced decrease in systolic blood pressure and increase in heart rate was obtained following peroral than sublingual administration despite the similar plasma concentrations of ISDN. This probably reflects the larger amount of pharmacodynamically active mononitrate metabolites formed after oral dosing. The integrated effect following administration of 2.5 mg ISDN as spray was similar to that of a sublingual tablet of 5 mg. 相似文献
55.
Granulocyte elastase levels do not correlate with anaerobic and aerobic bacterial growth in seminal plasma from infertile men 总被引:2,自引:0,他引:2
Seminal culture and leucocyte elastase measurements were undertaken on samples from 30 men attending an infertility clinic. Elastase levels over 1000 ng ml-1 were obtained in 14 men and positive bacterial culture in 11 men, but there was no correlation between these two sets of measurements. While granulocyte elastase measurement in semen may reflect inflammation, our study suggests that it cannot be used as a simple marker of infection particularly in a population such as ours where the prevalence of prostatitis and genital infection is low. 相似文献
56.
Immunoglobulin Gene Rearrangement in Plasma Cell Dyscrasias: Detection of Small Clonal Cell Populations in Peripheral Blood and Bone Marrow 总被引:1,自引:0,他引:1
Falko Fend Katharina Weyrer Johannes Drach Andrea Schwaiger Florian Umlauft Kurt Grü newald 《Leukemia & lymphoma》1993,10(3):223-229
The bone marrow (BM) and peripheral blood (PB) samples of 71 patients with plasma cell dyscrasias were analysed by the Southern blot technique for the presence of clonal immunoglobulin (Ig) gene rearrangements. 53% of BM samples examined were archival material such as air dried BM slides or frozen trephine biopsies. The results were related to bone marrow plasmacytosis as determined by cytology and flow cytometry, and other clinical parameters. Clonal Ig gene rearrangements were found in BM samples of 45 (83%) of 54 MM patients and in 3 of 6 patients with monoclonal gammopathy of unknown significance (MGUS). Clonal cell populations in the PB were detected in 11 (30%) of 37 examined MM patients, but in none of the patients with MGUS or solitary plasmacytoma of bone. PB involvement was associated with progressive disease. Circulating monoclonal cells were significantly associated with higher M-protein levels (p 0.05). Thus, circulating clonal precursor cells are encountered more frequently in active MM. 相似文献
57.
58.
福建产舟山眼镜蛇毒细胞毒素的快速分离纯化及鉴定 总被引:8,自引:4,他引:4
目的 从舟山眼镜蛇毒中分离纯化细胞毒素(CTX),并鉴定其理化性质。方法 采用SP—Sephadex C-25阳离子交换色谱及Sephasil Peptide C18反相高效液相色谱法从舟山眼镜蛇毒中分离纯化CTX,SDS—PAGE(Tris—Tricine系统)鉴定纯度,Edman降解法测定N端氨基酸序列。结果 粗毒经阳离子交换色谱,得到14个蛋白峰,其中第X~XⅢ峰具CTX活性;再分别经反相色谱纯化,得到4个CTX.总得率为32.48%;SDS—PAGE显示为均一蛋白,分子量依次为:7.28,7.33,7.24和7.38kD;测定它们N端20个氨基酸序列。结论 采用阳离子交换和反相高效液相色谱可快速、高效地从眼镜蛇毒中获得4个CTX纯品。 相似文献
59.
LOWER POSTPRANDIAL PLASMA GLUCOSE AND INSULIN AFTER ADDITION OF ACACIA CORIACEA FLOUR TO WHEAT BREAD
Many Australian Aboriginal bushfoods contain slowly digested carbohydrate which elicit low postprandial blood glucose and insulin responses compared to Western foods, such as wheat bread. This study has shown that incorporation of flour made from a slowly digested seed, Acacia coriacea , into wheat bread (18 g/82 g wheat flour) significantly reduces the initial rise in plasma glucose levels ( p < 0.05) and the area under the plasma glucose curve ( p < 0.005) in six healthy subjects. Insulin values were also lowered at 60 minutes ( p < 0.025) and 90 minutes ( p < 0.05). Our findings suggest that Acacia flour, when used to dilute wheat flour in the manufacture of breads, produces a very palatable food which could be useful in the diets of diabetic individuals. 相似文献
60.
J. Ludwig T. Halbrügge G. Vey J. Walter K. -H. Graefe 《European journal of clinical pharmacology》1989,37(5):493-500
Summary The total body clearance and fractional extraction of isoprenaline (ISO) have been determined, and the relation between these parameters and cardiac output established. Whether desipramine, an inhibitor of neuronal uptake, altered the plasma catecholamine response to ISO was also investigated.Seven healthy subjects were given i.v., infusions of ISO in two, consecutive 25-min periods, at constant dose rates of 31–43 and 80–124 pmol·kg–1·min–1, respectively. The total-body (ER), pulmonary (ERp) and forearm (ERf) fractional extractions and the total body clearance (CL) of ISO were obtained from measurements of cardiac output and the steady-state ISO concentration in mixed central venous, arterial and forearm venous plasma.ISO-induced increases in cardiac output resulted in increases in CL, decreases in ER and no consistent change in ERf. ERp did not differ from zero. ISO also produced a dose-dependent increase in the mixed venous plasma concentrations of noradrenaline and 3,4-dihydroxyphenylglycol (DOPEG), and a decrease in that of adrenaline. Pretreatment with desipramine did not alter any of the pharmacokinetic parameters of ISO. Desipramine, however, reduced the mixed venous baseline plasma levels of noradrenaline (47%) and DOPEG (40%), and tended to reduce that of adrenaline (34%). It enhanced the plasma noradrenaline response 2.4-fold, abolished the plasma DOPEG response and did not alter the plasma adrenaline response to ISO.Hence, owing to its haemodynamic effects, ISO modifies its own pharmacokinetics which involve non-neuronal removal processes only. The increased DOPEG in plasma resulting from the ISO-induced increase in noradrenaline release was presynaptic in origin. Desipramine appears to reduce sympathetic activity. The enhancement by desipramine of the ISO-induced increase in plasma noradrenaline points towards recapture by neuronal uptake of at least 58% of the noradrenaline released in response to ISO. 相似文献