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41.
Eleven male volunteers were studied to compare the airway irritation produced by the four anaesthetic agents: halothane, enflurane,
isoflurane and sevoflurane at two concentrations, equivalent to one and two MAC. Tidal volume, respiratory frequency and functional
residual capacity changes induced by 15 sec inhalation of the anaesthetics were measured using respiratory inductive plethysmograph.
Appearance of the cough reflex was also observed. The order of subjective airway irritation was evaluated by the volunteers.
Inhalation of the anaesthetic agents induced a decrease in tidal volume, increase in respiratory frequency and decrease in
functional residual capacity. Significant changes were considered to have occurred if tidal volume and respiratory frequency
changed by more than 30% from the resting values for at least ten seconds, or if functional residual capacity changed by more
than 30% of the value at resting tidal volume, for at least ten seconds. Each change was induced most frequently by isoflurane
followed by enflurane, halothane and, least frequently, by sevoflurane. The orders of appearance of the cough reflex and of
subjective airway irritation were similar. Sevoflurane did not elicit a cough reflex. It is concluded that sevoflurane was
the least irritant anaesthetic and is considered to be the most suitable for inhalational induction of anaesthesia.
Sept volontaires du sexe masculin font partie dune étude visant à comparer les ejfets irritants de quatre agents anesthésiques
sur les voies respiratoires: l’halothane, l’enflurane, l’ isoflurane et le sévoflurane, à deux concentration qui équivalent
soit à MAC 1, soit à MAC 2. On mesure les changements de volume courant, de fréquence respiratoire et de capacité résiduelle
fonctionnelle à l’aide d’un pléthysmographie à induction. On note l’apparition du réflexe de toux. De plus, on évalue le degré
subjectif d’irritation éprouvé par les sujets. L’inhalation d’agents anesthésiques cause une baisse du volume courant, une
augmentation de la fréquence respiratoire et une diminution de la capacité résiduelle fonctionnelle. On considère significatifs
les changements de volume courant et de fréquence respiratoire de plus de 30% des valeurs de repos pour au moins dix secondes,
les changements de capacité résiduelle fonctionnelle de plus de 30% de sa valeur au volume courant de repos pour au moins
dix secondes. Les changements sont initiés principalement par l’isoflurane, suivi par l’enflurane, l’halothane et moins fréquemment
par le sévoflurane. L’ordre d’apparition du réflexe de toux et de l’impression subjective d’irritation des voies aériennes
est identique. Le sévoflurane ne provoque pas de réflexe de toux. On conclut que le sévoflurane est le moins irritant des
anesthesiques et qu’on peut le considerer comme celui qui convient le mieux à l’induction de l’anesthésie par inhalation. 相似文献
42.
This study was conducted to assess the effect of sevoflurane on lung resistance and compliance, and its responsiveness to
histamine. We studied eight dogs to compare the effect of sevoflurane, isoflurane, enflurane, and halothane on bronchoconstriction
caused by histamine. Baseline values of pulmonary resistance (RL) and dynamic pulmonary compliance (Cdyn) were measured prior to administration of histamine. Histamine (2, 4, and 8 μg · kg−1) were administered iv, and the values of RL and Cdyn at the time of peak effect were recorded. Under 1 or 2 MAC anaesthesia, sevoflurane as well as the other three anaesthetics
had no bronchoactive effects. The four anaesthetics, including sevoflurane, demonstrated inhibitory effect on increases in
RL and decreases in Cdyn caused by histamine. At 1 MAC anaesthesia, % changes in RL caused by 2, 4, or 8 μg · kg−1 of histamine were 38 ± 11, 85 ± 21, or 132 ± 24% (mean ± SE) for halothane, and 65 ± 11, 132 ± 15, or 172 ± 19% for sevoflurane,
respectively. Sevoflurane was less effective than halothane in preventing increases in RL. In preventing decreases in Cdyn, sevoflurane was less effective than halothane only at 8 μg · kg−1 of histamine under 1 and 2 MAC anaesthesia. There was no difference in attenuating effect on changes in RL and Cdyn between sevoflurane and isoflurane or enflurane. We concluded that sevoflurane was less potent than halothane in attenuating
changes in RL and Cdyn in response to iv histamine.
Cette étude a été réalisée dans le but d’évaluer les effets du sévoflurane sur la résistance et la compliance pulmonaires
en réponse à l’histamine. Les effets du sévoflurane, de l’isoflurane, de l’enflurane et de l’halothane sur la bronchoconstriction
induite par l’histamine sont comparés sur huit chiens. Avant l’administration d’histamine, on mesure les valeurs initiales
de la résistance (RL) et de la compliance dynamique (Cdyn) pulmonaires. L’histamine (2, 4, 8 μg · kg−1) est administrée par la voie veineuse et les valeurs maximales de la RL et de la Cdyn sont enregistrées. Les quatre anesthésiques, dont le sévoflurane inhibent l’augmentation de la RL et la diminution de la Cdyn provoquées par l’histamine. A MAC 1 d’anesthésie, les pourcentages de changement de RL produits par 2, 4, ou 8 μg · kg−1 d’histamine sont respectivement de 38 ± 11, 85 ± 21, ou 132 ± 24% (moyenne + SD) pour l’halothane, et de 65 ± 11, 132 ± 15,
ou 172 ± 19% pour le sévoflurane. Le sévoflurane est moins efficace que l’halothane pour prévenir les augmentations de RL. Le sévoflurane est moins efficace pour prevenir la diminution de Cdyn mais seulement à 8 μg · kg−1 d’histamine sous anesthésie à MAC 1 et 2. Le sévoflurane, l’halothane et l’isoflurane ne sont pas de différents pour amortir
les changements de RL et Cdyn. Nous concluons que le sévoflurane est moins puissant que l’halothane pour diminuer la réponse à l’histamine de la RL et de la Cdyn. 相似文献
43.
Shigematsu Y Korogi Y Hirai T Okuda T Sugahara T Liang L Takahashi M 《Journal of magnetic resonance imaging : JMRI》1999,10(6):939-944
This work investigated whether turbo magnetic resonance angiography (MRA) can replace conventional MRA in screening examination of intracranial arteries. A phantom was used to evaluate the effect of the zero-filling interpolation (ZFI) technique on spatial resolution and partial volume effect. Thirty-one consecutive patients underwent both turbo MRA with a slice thickness of 0.7 mm (data were measured as 1.33 mm sections) and conventional MRA with 1.0 mm sections. In the phantom studies, ZFI did not improve the spatial resolution, but the partial volume effect was somewhat reduced. In the clinical evaluation, turbo MRA showed better signal-to-noise and contrast-to-noise ratios of the intracranial major vessels than conventional MRA. The lesions included cerebral aneurysms less than 3 mm in diameter, occlusive vascular disease, arteriovenous malformations, and arteriovenous fistulas. These were all depicted on both turbo MRA and conventional MRA. Turbo MRA is a useful screening procedure because of its capability of delineating lesions in approximately half the usual imaging time. J. Magn. Reson. Imaging 1999;10:939-944. 相似文献
44.
Terashima Keisuke Takai Satomi Usami Yoshiko Adachi Tetsuo Sugiyama Tadashi Katagiri Yoshihiro Hirano Kazuyuki 《Pharmaceutical research》1996,13(9):1327-1330
Purpose. Indomethacin is well known to be metabolized via O-demethylation and N-deacylation. In this paper we found an enzyme involved in the hydrolysis of amide-linkage of indomethacin and partially characterized it as well as its substrate specificity.
Methods. An indomethacin hydrolyzing enzyme was purified to homogeneity from pig liver microsomes using columns of Q-Sepharose, Red-Sepharose and Blue-Sepharose. The enzyme activity was assayed by measuring of -chlorobenzoic acid liberated from indomethacin by HPLC.
Results. The purified enzyme effectively hydrolyzed the amide linkage in indomethacin but not those in -naphthylacetate and -nitrophenylacetate, which are typical substrates for carboxylesterase. The subunit molecular mass of the enzyme was 65 kDa according SDS-polyacrylamide gel electrophoresis. The Michaelis constant (Km) and maximum velocity (Vmax) values for indomethacin were 67.8 µM and 9.02 nmol/min/mg protein, respectively. The amino acid sequence analysis of the enzyme after cyanogen bromide cleavage showed high homology with a mouse carboxylesterase isozyme designated as ES-male. The activity of indomethacin hydrolysis was relatively high in the pig, rabbit and human liver homogenate, but not in those from rat and mouse. On the other hand, purified human liver carboxylesterases pl 5.3 and 4.5, and pig liver carboxylesterases have no catalytic activity for indomethacin.
Conclusions. These results indicate that the hydrolysis of amide-linkage of indomethacin in humans would be associated with an enzyme similar to the indomethacin hydrolyzing enzyme from pig liver microsomes described here. 相似文献
45.
Key words cardiac arrhythmias - oxygen uptake - carbon dioxide elimination 相似文献
46.
There has been no study comparing the advantage and disadvantage of various antihypertensive agents during surgery for pheochromocytomas because the study is difficult in clinical setting. In the present experiments using dogs, after increasing the arterial blood pressure with norepinephrine, we decreased it to the baseline with sodium nitroprusside (SNP), adenosine triphosphate (ATP), or phentolamine (PE) and compared the hemodynamic changes. A hyperdynamic state was found with ATP and with PE, but not with SNP. The norepinephrine-induced pulmonary hypertension could be successfully treated with SNP, but not with ATP or PE. The reason for these differences are thought to be the different vasodilative properties on peripheral arteries and veins. We conclude that agents that dilates the arteries and veins should be used to regulate the arterial pressure during surgical removal of a pheochromocytoma.(Murata K, Takahashi H, Ikeda K: Comparative cardiovascular effects of SNP, ATP and phentolamine during norepinephrine-induced hypertension in dogs. J Anesth 5: 396–403, 1991) 相似文献
47.
48.
The case of a patient with reappearing stupor, accompanied by auditory hallucinations and persecutory ideas during the periods and not with alternating excitement, is reported. After 24 years of neuroleptics medication with little effect, the lithium carbonate regimen was started, which showed a remarkable prophylactic effect. The implications of lithium carbonate treatment for recurrent psychosis are discussed. 相似文献
49.
50.
Kiyoshi Ohara Hideo Tatsuzaki Hiroshi Fuji Shinji Sugahara Toshiyuki Okumura Eiichi Akaogi Masataka Onizuka Shigemi Ishikawa Kiyofumi Mitsui Yuji Itai 《Acta oncologica (Stockholm, Sweden)》1998,37(5):471-474
Patterns of radiologic response of 10 thymomas treated by preoperative radiotherapy (RT) (18-20 Gy/2 weeks) were determined in conjunction with histologic response. Changes in tumor volume were evaluated with CT scans obtained 5 to 36 days before and 14 to 24 days after the initiation of RT and before surgery. The extent of tumor volume reduction (TR) varied widely (40-78%), while the mean daily volume decrement expressed as a percentage of the pre-RT tumor volume correlated significantly with the pre-RT tumor volume. Histologically, the tumors, all of which were resected 17 to 33 days after RT initiation, generally consisted of predominant fibrous tissues, rare necrotic foci, and few epithelial cells. The TR did not correlate with pre-RT tumor volume, observation period, histologic subtype, or quantity of remaining epithelial cells. The TR of thymomas does not predict RT impact on tumor cells but does reflect the quantity of inherent tumor stroma. 相似文献