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21.
Masahiko Kawaguchi Masakazu Kuro Hisatoshi Ohsumi Toshito Nakajima Yoshihiro Kuriyama Jun Karasawa 《Journal of anesthesia》1994,8(1):60-63
We assessed the local cerebral blood flow (LCBF) in 40 patients under fentanyl-diazepam anesthesia. The measurement of LCBF
was made using 50%–70% stable xenon with 20 min of inhalation interval and a shuttle method for computed tomography imaging.
All patients were anesthetized with 5.95±1.76 μg·kg−1 fentanyl and 0.22±0.07 mg·kg−1 diazepam under mechanical ventilation during CBF measurement. The values and distribution of LCBF on non-affected hemisphere
appeared to be unaltered by fentanyldiazepam anesthesia. We also assessed the cerebral carbon dioxide reactivity in 6 patients.
The cerebral carbon dioxide reactivity, expressed as percentage change in LCBF per unit change in arterial carbon dioxide
partial pressure, was 5.39±1.07, and there were no significant differences of reactivity among regions studied. In conclusion,
we showed reference values of LCBF and carbon dioxide reactivity, measured by stable xenon-enhanced computed tomography, in
patients under fentanyl-diazepam anesthesia. Carbon dioxide reactivity was preserved in all regions including gray matter,
white matter, and basal ganglia. 相似文献
22.
Chang CY Chen YL Yang SC Huang GC Tsi D Huang CC Chen JR Li JS 《Phytotherapy research : PTR》2009,23(2):251-256
To study the effects of schisandrin B and sesamin mixture on carbon tetrachloride (CCl(4))-induced hepatic oxidative stress in male Sprague-Dawley rats. The rats were randomly assigned to five groups: control group (olive oil injection), CCl(4) group (CCl(4) injection), silymarin group (CCl(4) injection combined with supplementation of silymarin, 7.5 mg/kg/day), low dose group (CCl(4) injection combined with supplementation of schisandrin B and sesamin mixture at a low dose, 43 mg/kg/day) and high dose group (CCl(4) injection combined with the supplementation of schisandrin B and sesamin mixture at a high dose, 215 mg/kg/day). The hepatic superoxide dismutase and glutathione peroxidase activities of rats in the low dose and high dose groups were increased significantly compared with those in the CCl(4) group. The hepatic reduced glutathione concentration in the silymarin, low dose and high dose groups were increased significantly (48%, 45% and 53%, respectively) when compared with those of the CCl(4) group. In addition, the concentration of glutathione in the erythrocytes of the low dose group was significantly higher than the CCl(4) group by 25%. These results suggest that the schisandrin B-sesamin mixture exerted a hepatoprotective effect by improving the antioxidative capacity in rats under CCl(4)-induced hepatic oxidative stress. 相似文献
23.
Toshiaki Nakashima Fuminori Goda Jinge Jiang Toshihide Shima Harold M. Swartz 《Magnetic resonance in medicine》1995,34(6):888-892
The partial pressure of oxygen (pO2) of the liver in vivo in unanesthetized mice was determined using electron paramagnetic resonance (EPR) oximetry with India ink. The EPR spectra were obtained using a low-frequency (1.2 GHz) EPR spectrometer with a loop gap cavity resonator. The line width of the India ink used in this experiment was reversibly broadened by oxygen and was particularly sensitive to pO2 below 30 torr. After the administration of India ink into the tail vein, the India ink particles were taken up mainly by Kupffer cells in the liver and in part by phagocytes in the spleen. The pO2 measured in the normal liver was about 14 torr and was constant for the 2-week experimental period. The pO2 decreased when measured at 1, 2, and 6 days after treatment with a hepatotoxin (carbon tetrachloride (CCI4)); within 2 weeks, it returned almost to the initial level. Measurements by EPR at sacrifice of controls and CCI4-treated mice indicated that more than 90% of the India ink went to the liver; the spleen contained 4.7% of total amount in control mice and 8.8% in CCI4-treated mice when measured 2 weeks after the treatment. These data indicate the usefulness of India ink for measuring the pO2 of the liver in vivo and that the pO2 in the Kupffer cells is decreased when the liver is damaged by CCI4. 相似文献
24.
Takahito Adachi Makoto Takeuchi Satomi Uno Motohisa Kato Kiichi Miya Shigetoyo Saji 《Surgery today》1997,27(12):1144-1149
Although tumor cryosurgery would be expected to produce beneficial immunological effects from the enhancement of anti-tumor
activity, under certain conditions the tumor may become enlarged and metastases promoted due to increased immunosuppressive
activity and a high zone tolerance. In the present study, we examined whether hepatocyteproliferating factors were produced
by the inoculation of freezing-thawing hepatic tissue (FTHT). Serum obtained from rats inoculated with FTHT increased DNA
synthesis, according to measurement by [3H]thymidine incorporation in primary cultured rat hepatocytes. This increase was dependent on the serum concentration, with
serum obtained on day 14 after the inoculation being the most potent for hepatocyte proliferation. The sensitized serum promoted
DNA synthesis nearly as much as serum obtained from a 70% hepatectomized rat, but slightly less than 10ng/ml hepatocyte growth
factor. The sensitized serum also protected hepatocytes from carbon tetrachloride (CCI4)-induced hepatotoxicity. Optical density measured by the 3-(4,5-dimethyl-thiazole-2-yl)-2,5-diphenyl tetrozolium bromide
(MTT) cytotoxicity assay was increased, and the release of aspartate aminotransferase, alanine aminotransferase, and lactate
dehydrogenase in medium was decreased by treating hepatocytes damaged by CCI4 with the sensitized serum. These results suggest that certain hepatocyte-proliferating and protective factors are induced
in serum by the inoculation of freezing-thawing hepatic tissue, and that the sensitized serum may be useful in the treatment
of liver failure. 相似文献
25.
二氧化碳对白纹伊蚊的引诱作用 总被引:5,自引:4,他引:1
目的 测试二氧化碳(CO2)浓度与诱效率之间的关系,探明CO2对白纹伊蚊种群的引诱作用,以提高诱蚊灯的诱蚊效果。方法 不同浓CO2运用化学反应获取,通过诱蚊试验测定诱杀率反应诱杀效果。结果:探索出一个对白纹伊蚊具有较好引诱效应的CO2浓度10.34pp,与SB980型紫外光诱蚊灯结合试验表明,用CO2后对白纹伊蚊的诱杀率比对照灯提高13%—30%,平均20%。结论 浓度很低的CO2即对蚊虫有引诱效应,并能增强诱蚊灯的诱杀效果,满足无公害无污染的要求;实验为现有除虫产品的改良提供了一条新途径。 相似文献
26.
In vivo carbon monoxide exposure and hypoxic hypoxia stimulate immediate early gene expression 总被引:4,自引:0,他引:4
Bernhard Gess Konrad Wolf Michael Pfeifer Günter A. J. Riegger A. Kurtz 《Pflügers Archiv : European journal of physiology》1997,434(5):568-574
This study aimed to examine the influence of acute tissue hypoxygenation on the expression of immediate early genes in different
rat tissues. To this end male Sprague-Dawley rats were exposed to 0.1% carbon monoxide for 0.5, 1 and 6 h or to 9% oxygen
for 6 h and mRNA levels for c-jun, c-fos, c-myc and EGR-1 were assayed by RNase protection in hearts, kidneys, livers and lungs. We found that hypoxia increased c-jun mRNA levels between twofold (lung) and eightfold (liver) in all organs examined; c-fos mRNA increased between threefold (lung) and 20-fold (heart); c-myc mRNA increased between twofold (lung) and sixfold (heart); and EGR-1 mRNA increased between twofold (lung) and sixfold (heart).
Our findings suggest that acute tissue hypoxygenation is a general stimulus of the expression of immediate early genes in
vivo. With regard to the sensitivity to hypoxia, organ differences appear to exist in that the lung is rather insensitive,
whilst the heart is rather sensitive.
Received: 25 February 1997 / Received after revision: 17 June 1997 / Accepted: 19 June 1997 相似文献
27.
本研究分别给四组大鼠注射CCl_4、P_4、TNT及纯生油,进行亚慢性实验,在不同的时间处死动物,测定血清及肝组织NAG、CP、MAO、羟脯氨酸和肝组织病理观察。CCl_4染毒3周后就发生肝纤维化;P_4和TNT染毒12周后才发生肝纤维化。血清中NAG、CP及肝组织中NAG、羟辅氨酸含量在肝纤维化早期即有明显升高,其中血清NAG、CP与肝组织中羟脯氨酸含量有明显正相关关系。血清NAG、CP似可以用作了解肝纤维化情况的指标。 相似文献
28.
Danuta Knapikowa Zbigniew Andreasik Stefan Kwiatkowski Marek Okrojek Roman Smolik Krzysztof Szczerba 《International archives of occupational and environmental health》1988,60(5):351-353
Summary We examined 81 men exposed for a long time to carbon disulphide (CS2) and tested the possible electrocardiographic (ECG) changes of ischemic heart disease (I.H.D.). The subjects were examined twice in two years. In order to make the ECG evaluation more objective, the Minnesota Code was applied. Two obligatory ECG examinations and only one submaximal effort test were carried out. For comparative evaluation, the control group was examined once. We proved that, in spite of the accepted opinion concerning the atheromatous action of CS2, this compound does not cause ECG symptoms of I.H.D. in a higher percentage of exposed persons. It also does not cause any significant increase in I.H.D. symptoms in dynamic ECG observations. 相似文献
29.
《Journal of labelled compounds & radiopharmaceuticals》2003,46(7):605-611
JTT‐501 specifically labelled with 13C was obtained via a four‐step synthesis at an isotopic enrichment level of 99% and in 14% overall chemical yield starting from 4‐hydroxy‐[ring‐U‐13C6]benzaldehyde (3) . The hydrogenation of [13C6]JTT‐501 over Pd/C gave [13C6]JTP‐20604 in 90% chemical yield. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
30.
一些保肝药物对原代培养大鼠肝细胞糖原合成功能的影响 总被引:1,自引:0,他引:1
本文参照PO Seglen的方法并加以修改,建立了原代培养大鼠肝细胞糖原合成功能的测定体系。观察到联苯双酯既能使正常肝细胞合成糖原增加88%,又能保护肝细胞完全拮抗四氯化碳对其功能的损伤;银耳多糖能使四氯化碳对肝细胞糖原合成功能的损伤减轻57%;去甲斑蝥素10μg/ml能增加肝细胞糖原合成,浓度增加到100μg/ml时,此作用减弱,1000μg/ml则明显抑制糖原的合成,而且在10~100μg/ml浓度时,即能加强四氯化碳的损伤作用;100μg/ml CL1500和熊果酸二钠单独应用可增加肝细胞糖原合成,但与四氯化碳同时应用,反而加重对糖原合成的抑制作用。 相似文献