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991.
992.
Lack of antinociceptive activity of sumatriptan in rodents 总被引:1,自引:0,他引:1
Malcolm Skingle Phillip J Birch Glynnis E Leighton Patrick PA Humphrey 《Cephalalgia : an international journal of headache》1990,10(5):207-212
The present study attempts to determine whether the novel anti-migraine drug sumatriptan has antinociceptive activity in rodents. Sumatriptan had little or no antinociceptive activity against a range of noxious stimuli and we therefore conclude that it is unlikely that the beneficial effects of the drug in treating migraine are due to a non-specific analgesic action. 相似文献
993.
DL-2-amino-5-phosphonovaleric acid (APV), a specific antagonist of N-methyl-D-aspartate (NMDA) receptors, was administered alone and in combination with scopolamine (SCO), an antagonist of muscarinic cholinergic receptors, to different groups of rats undergoing electrical kindling of the amygdala. Both groups were significantly retarded in their rate of kindling during 15 drug sessions compared to controls, and the group receiving APV and SCO kindled significantly slower than the group receiving APV alone. These results indicate that both NMDA and muscarinic cholinergic receptors are involved in kindling of the amygdala, and implicate a mechanism involving the summation of excitatory neurotransmission in kindling of the amygdala. 相似文献
994.
995.
CM Hunter HP Niles J Vazquez C Kloos R Subramanyam MI Williams D Cummins PA Lenton GJ Majerus 《Oral diseases》2005,11(S1):48-50
Background: Detection of oral volatile sulfur compounds (VSC) by gas chromatography (GC) is a widely used method for evaluating breath odor. Air aspirated from the mouth is injected into the GC column for analysis. To eliminate discrepancies caused by variations in operator sampling or injection techniques, a new GC system designed to aspirate breath samples directly into the GC was developed.
Objective: A clinical study was performed to compare this new automated breath-sampling GC system to organoleptic evaluation by two trained odor judges.
Methods: A randomized, two-cell, double-blind, parallel design was used in which subjects were tested before and 3 h after using either a mouthrinse containing zinc or a matching placebo rinse. Thirteen subjects used the zinc mouthrinse, and 12 used the placebo. Subjects with a wide range of VSC levels were studied. The average organoleptic ratings for each subject at each time-point were compared with the average VSC measurements made with the GC, and Pearson product–moment correlation coefficients between the corresponding GC and organoleptic measurements were determined.
Results: The correlation between the GC and organoleptic assessment methods were highly significant ( P ≤ 0.001) for: total VSC, 0.65; H2 S, 0.63; CH3 SH, 0.61; and (CH3 )2 S, 0.46. The correlation between the two judges was also highly significant (0.823, P < 0.001).
Conclusion: These results demonstrate the utility of the automated GC method for evaluating breath odor. 相似文献
Objective: A clinical study was performed to compare this new automated breath-sampling GC system to organoleptic evaluation by two trained odor judges.
Methods: A randomized, two-cell, double-blind, parallel design was used in which subjects were tested before and 3 h after using either a mouthrinse containing zinc or a matching placebo rinse. Thirteen subjects used the zinc mouthrinse, and 12 used the placebo. Subjects with a wide range of VSC levels were studied. The average organoleptic ratings for each subject at each time-point were compared with the average VSC measurements made with the GC, and Pearson product–moment correlation coefficients between the corresponding GC and organoleptic measurements were determined.
Results: The correlation between the GC and organoleptic assessment methods were highly significant ( P ≤ 0.001) for: total VSC, 0.65; H
Conclusion: These results demonstrate the utility of the automated GC method for evaluating breath odor. 相似文献
996.
Specialists and generalists in obstetrics and gynecology: conflicts of interest in referral and an ethical alternative. 总被引:1,自引:0,他引:1
Referral patterns of physicians have a direct impact upon the care of patients, particularly in obstetrics and gynecology. The choice of referral is influenced by the history of specialization, physician altruism, and intricate patterns of financial conflicts of interest. The conflicts of interest are further obscured by the lack of clear definition of roles and responsibilities for generalist, specialist, and subspecialist. Alternate patterns for referral based on financial incentives or directed referral care plans are reviewed to examine the potential conflicts of interest. An ethics-based format for referral is outlined to address these conflicts of interest. 相似文献
997.
In November 1987 we began to practice delayed repair of acutely symptomatic congenital diaphragmatic hernia (CDH) following medical and/or extracorporeal membrane oxygenation (ECMO) stabilization. We reviewed 23 consecutive patients with CDH symptomatic at birth treated over the ensuing 2 1/2 years. The mean age at admission, age at repair, and interval from admission to repair were 4.9, 37.0, and 32.6 hours, respectively. Overall survival was 52% (12/23). ECMO was used in 14 patients with 7 survivors (50%); 4 of these patients underwent repair prior to ECMO and 10 while on ECMO. The patients were retrospectively grouped into three classes based on postductal arterial blood gas (ABG) response to conventional medical management: class A (n = 8), able to achieve and sustain adequate oxygenation (PO2 greater than 60 mm Hg) and hyperventilation (PCO2 less than 40 mm Hg); class B (n = 10), unable to sustain adequate oxygenation (PO2 less than 60 mm Hg) but able to be hyperventilated (PCO2 less than 40 mm Hg); and class C (n = 5), unable to be oxygenated (PO2 less than 60 mm Hg) or hyperventilated (PCO2 greater than 40 mm Hg). The interval from admission to repair was 13.6, 53.5, and 25.4 hours for classes A, B, and C, respectively. Two class A (25%), nine class B (90%), and three class C patients (60%) were placed on ECMO. Survival rates were 88%, 50%, and 0% for classes A, B, and C, respectively. We propose the following management protocol. Class A patients are stable and can be repaired at any convenient point after admission without prerepair ECMO; few will need it afterward.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
998.
An intrahepatic arterial-portal venous malformation (APVM) was diagnosed in a 4 1/2-month-old infant with portal hypertension. Visceral angiography showed a large saccular vascular space in the left hepatic lobe with a multiplicity of feeding arteries and drainage into the left portal vein. The lesion was successfully treated by transcatheter embolization following two unsuccessful surgical procedures. Two years later portal vein thrombosis with cavernous transformation was diagnosed, possibly a consequence of the high-flow arterial-portal shunt and its subsequent occlusion. Knowledge of the anatomic differences between this rare congenital APVM and the more commonly occurring arterial-portal fistula is crucial in planning effective transcatheter embolotherapy or surgery for these lesions. 相似文献
999.
Duodenal mucosal ferritin in rheumatoid arthritis: implications for anaemia of chronic disease 总被引:1,自引:0,他引:1
O'Toole PA; Sykes H; Phelan M; Thompson RN; Lombard MG 《QJM : monthly journal of the Association of Physicians》1996,89(7):509-514
Anaemia is a common feature of rheumatoid arthritis (RA) and other chronic
diseases. Among the alterations in iron metabolism contributing to this
effect is a decrease in intestinal iron absorption. The mechanism for this
is unknown, but might involve a 'mucosal block' process similar to that
proposed in iron overload, whereby increased expression of an enterocyte
storage protein binds absorbed iron and prevents its transfer to the
circulation. We examined the effect of disease-modifying therapy on
ferritin expression in duodenal mucosa in RA to determine whether it may
play a role in the 'mucosal block' process. Endoscopic small bowel biopsies
were obtained from 11 patients with active RA both before, and 6 months
after, a course of either gold or methotrexate (MTX). Mucosal ferritin
levels in small bowel and stomach were measured by radio-immune assay.
Duodenal mucosal ferritin decreased significantly following treatment (p
<0.05). There were no changes in gastric mucosal ferritin. The fall
in duodenal mucosal ferritin correlated with indices of disease activity at
start of therapy, and the largest decreases were in those patients showing
the best response to treatment in terms of a fall in inflammatory markers.
Site-specific changes in mucosal ferritin may underlie the altered iron
absorption observed in active inflammatory disease by modifying the
enterocyte 'mucosal block'.
相似文献
1000.