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排序方式: 共有660条查询结果,搜索用时 46 毫秒
41.
A R Coggan R J Spina W M Kohrt D M Bier J O Holloszy 《International journal of sport nutrition》1991,1(3):279-288
We hypothesized that when plasma glucose availability is maintained by carbohydrate (CHO) ingestion, trained cyclists can utilize plasma glucose at very high rates during the later stages of prolonged exercise (10). To test this hypothesis, a well-trained male cyclist was studied during exercise to fatigue at 70% VO2max when ingesting glucose throughout exercise. A primed continuous infusion of [U-13C]glucose was begun after 60 min of exercise to measure rates of plasma glucose appearance (Ra), disappearance (Rd), and oxidation (R(ox)). Ra and Rd rose progressively throughout exercise, peaking at 6.85 and 6.99 mmol/min, respectively, at fatigue (i.e., 133 min). Most (93%) of this glucose was oxidized; during the final 30 min of exercise, R(ox) averaged 6.10 mmol/min and accounted for approximately half of total CHO oxidation. These results support the hypothesis that trained cyclists can oxidize plasma glucose at very high rates during the later stages of prolonged exercise when fed CHO. 相似文献
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43.
Background
Hadjelia truncata is a nematode that causes lesions in the gizzard lining of pigeons, which may even lead to death. The aim of this study was to introduce Alphitobius diaperinus as a new intermediate host for Hadjelia truncata.Methods
H. truncata infection was identified in a pigeon flock in Ahvaz City, Khuzestan Province, Iran by performing fecal examination and autopsy. Adult and larval stages of beetles were collected from the litter of pigeon houses, and identified morphologically. The beetle larvae were cultured in a medium, containing feces of the infected pigeons. Nematode larval stages from naturally and experimentally (culturally) infected adult beetles were fed to two groups of pigeonsResults
The collected beetles were identified as Alphitobius diaperinus. Average length and width of the adult beetles were 6.31 mm and 2.88 mm respectively. Infection rates of naturally and experimentally infected beetles with larval stages of the nematode were 66.2% and 45.1% respectively. The adult nematodes collected from gizzards of experimentally infected pigeons were identified as H. truncata. Nematode infection rates in pigeons after feeding the infective larvae collected from naturally and experimentally infected beetles were 44.7% and 32.5% respectively.Conclusion
A. diaperinus can serve as a natural intermediate host for H. truncata. 相似文献44.
M Tavassoli S Javadi R Firozi F Rezaei AR Khezri M Hadian 《Iranian Journal of Parasitology》2012,7(4):110-115
Background
We tried to investigate the hair contamination of pet dogs and farm sheepdog with Toxocara eggs in terms of the different sex and age groups in north-west of Iran (Urmia and its suburbs).Methods
Hair samples were collected from a total of 138 pet and farm sheepdogs from November 2008 to June 2009 in Urmia City and the suburb (West Azerbaijan-Iran) and examined for the presence of T. canis eggs.Results
T. canis eggs found in 60 samples altogether (pet and shepherd dogs) showed a contamination rate of 36.2%. The number of observed T. canis eggs in each microscope field was varied from 1 to > 400. The age of the dog was found a significant factor to influence the prevalence and intensity of contamination, with 82% of all the eggs recovered from puppies (six months and younger). Additionally, the numbers of eggs in farm sheepdogs were significantly higher than pet dogs (P<0.05).Conclusion
This report shows that direct contact with T. canis infected dogs, particularly puppies from shepherd dogs, may pose a serious hazard to human. Besides, as they may harbor a considerable number of eggs on their hair, they can contaminate the soil and the environment. 相似文献45.
AR Genazzani G Sandrini F Facchinetti V Rizzo E Alfonsi G Sances M Calvani G Nappi 《Cephalalgia : an international journal of headache》1986,6(4):241-245
L-Tryptophan (L-TP) has been used in migraine and other pain conditions. The mechanism underlying the analgesic effect is still partly undefined. In this study the effects of subchronic administration of L-5-hydroxy-tryptophan (L-5HTP) (with and without carbidopa) on plasma beta-endorphin (beta-EP) levels and subjective pain threshold and tolerance were investigated in seven healthy volunteers. To measure also an objective indicator for pain, the nociceptive flexion reflex threshold was studied. L-5HTP treatment with and without carbidopa administration increased beta-EP levels significantly (p less than 0.05). L-5HTP plus carbidopa induced an increase in beta-EP significantly (p less than 0.05) higher than that after L-5HTP alone. Neither subjective pain threshold and tolerance nor RIII threshold was modified by either treatment. Our data seem to point to the existence of a complex linkage between plasma opioid levels and pain perception. 相似文献
46.
Peptic ulcer and gastric carcinoma: diagnosis with biphasic radiography compared with fiberoptic endoscopy 总被引:1,自引:0,他引:1
Shaw PC; van Romunde LK; Griffioen G; Janssens AR; Kreuning J; Eilers GA 《Radiology》1987,163(1):39-42
The diagnostic value of biphasic radiographic examination of the stomach and duodenum was compared with that of fiberoptic endoscopy in a prospective, blinded study of 385 patients with dyspepsia. This investigation was directed at gastric malignancies and peptic ulcers. Methodologically there is no absolute standard for a study of this kind because histologic examination is useful for detection of cancer but inadequate for ulcers. As an alternative, kappa indexes and the sensitivity and specificity, as derived by Hui and Walter, were calculated and compared. For the detection of gastric carcinoma, radiographic and endoscopic findings had almost perfect agreement beyond chance. For gastric ulcers, radiography and endoscopy had substantial agreement, which became perfect if small ulcers (less than 5 mm) were excluded. For duodenal ulcers, radiography had a lower sensitivity than endoscopy; this disagreement disappeared if small ulcers were excluded. Both methods have equal merit; choice of the initial diagnostic procedure will therefore depend on cost, discomfort to the patient, and risk of complications. 相似文献
47.
Douglas C. Scott John W. Coggan Charles A. Cruze Tao He Robert D. Johnson 《Journal of pharmaceutical sciences》2009,98(10):3862-3870
A pharmacokinetic model was developed describing the pharmacokinetics of stannous fluoride in human subjects after oral topical application of a stannous fluoride dentifrice. Twenty subjects participated in an investigation of an experimental dentifrice. Subjects rinsed their mouths with the experimental dentifrice slurry. Saliva and plaque samples were obtained from the subjects at various times up to 6 h after administration. Samples were analyzed for total tin content, used as an analytical marker for the active stannous fluoride ingredient, using a graphite furnace atomic absorption spectrometer. The modeling indicates that there is an obvious kinetic relationship between saliva and plaque compartments and that stannous fluoride is very well retained in and slowly released from plaque (and oral surfaces) into saliva. Additionally, both compartments are simultaneously loaded during administration unlike typical systemic drug behavior, and the elimination rate “constant” from the central compartment (saliva) changes due to changes in salivary flow. Stannous fluoride is cleared from saliva rapidly but very well retained in gingival plaque. The model with simultaneous loading of plaque and saliva describes these observations and may account for the prolonged antiplaque and antigingivitis benefits of stannous fluoride. © 2009 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 98:3862–3870, 2009 相似文献
48.
49.
ANDERSON G; COLES ET; CRANE M; DOUGLAS AC; GIBBS AR; GEDDES DM; PEEL ET; WOOD JB 《QJM : monthly journal of the Association of Physicians》1992,83(3):427-438
In order to describe the British experience of Wegener's granuiomatosisHospital Activity Analysis was used to collect cases diagnosedin England, Wales and Scotland between 1975 and 1985. Wherepossible clinical details, histological material and chest radiographswere obtained. Two hundred and sixty five patients were consideredto have Wegener's granuiomatosis. In 109 a single pathologistconfirmed the diagnosis by finding both granulomas and vasculitisin biopsy material. The diagnosis was made on clinical groundsor clinical grounds together with histological diagnosis inthe local hospital in 156 patients. Wegener's granuiomatosiswas confined to the lung or upper respiratory tract in 22 percent of patients and renal disease occurred in 58 per cent.Laboratory tests showed a pattern of mild anaemia, polymorphleucocytosis, eosinophilia and an elevated ESR and hypergammaglobulinaemia,with no specific pattern of changes. Histological confirmation was most frequently obtained by examinationof nasal biopsy specimens, but multiple biopsies were oftenrequired. Renal biopsies showed focal proliferative glomerulonephritisbut granulomatous glomerulonephritis was uncommon. Of availablechest radiographs 61 per cent were abnormal, large opacitiesbeing most common. Small irregular opacities were found lessoften and other abnormalities were uncommon. Treatment varied widely and 10 per cent of patients receivedno drug therapy. This large series illustrates that even withoutspecific treatment, patients with Wegener's granuiomatosis cansurvive for several years and with modern treatment survivalfor more than a decade is possible. Conclusions about the effectivenessof the various therapies cannot be drawn from this restrospectivestudy. Renal failure and disseminated vasculities were the commonestcauses of death; death was considered to result from complicationsof treatment with cytotoxic drugs or prednisolone in 6 per centof patients. 相似文献
50.
Pathway of free fatty acid oxidation in human subjects. Implications for tracer studies. 总被引:2,自引:1,他引:2 下载免费PDF全文
L S Sidossis A R Coggan A Gastaldelli R R Wolfe 《The Journal of clinical investigation》1995,95(1):278-284
To determine the pathway of plasma FFA oxidation and the site(s) of label fixation observed during infusion of FFA tracers, [1-13C]palmitate and [1-14C]acetate were infused intravenously for 3 h in five volunteers. Breath 13CO2 enrichment and 14CO2 specific activity were followed for 6 h to determine the labeled CO2 decay rates. Acetate enters directly into the TCA cycle; hence, if palmitate transits a large lipid pool before oxidation, 13CO2 enrichment (from palmitate) should decay slower than 14CO2 specific activity (from acetate). Breath 13CO2 enrichment and 14CO2 specific activity decayed at a similar rate after stopping the tracer infusions (half-lives of 13CO2 and 14CO2 decay: mean [+/- SE] 106.6 +/- 8.9 min, and 96.9 +/- 6.0 min, respectively, P = NS), which suggests that palmitate enters the TCA cycle directly and that label fixation occurs after citrate synthesis. Significant label fixation was shown in plasma glutamate/glutamine and lactate/pyruvate during infusion of either [1,2-13C]acetate or [U-13C]palmitate, suggesting that TCA cycle exchange reactions are at least partly responsible for label fixation. This was consistent with our finding that the half-lives of 13CO2 enrichment and 14CO2 specific activity decreased significantly during exercise to 14.4 +/- 3 min and 16.8 +/- 1 min, respectively, since exercise significantly increases the rate of the TCA cycle in relation to that of the TCA cycle exchange reactions. We conclude that plasma FFA entering cells destined to be oxidized are directly oxidized and that tracer estimates of plasma FFA oxidation will underestimate the true value unless account is taken of the extent of label fixation. 相似文献