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81.
The modulation of drug metabolising enzymes by Masheri extract (ME) and Benzo(a)Pyrene [B(a)P] was studied in male Sprague Dawley rats fed different dietary protein levels. Two groups of 21 days old male Sprague Dawley rats were put on a high protein diet (SHP) with 20% Casein, and a low protein diet (SLP) with 3% Casein semisynthetic based diets for 12 weeks. The SLP fed animals showed lower basal levels of the Phase I activating enzymes viz. Cytochrome P450, Benzo(a)Pyrene hydroxylase, Benzphetamine demethylase and Phase II glutathione detoxification system viz. Glutathione (GSH) and Glutathione-S-transferase. ME and B(a)P treatment significantly depleted the glutathione detoxification system in the SLP group whereas an opposite effect was observed in the SHP group. Interstingly, ME and B(a)P treated rats in the SLP group showed a higher percent increase in the hepatic and pulmonary Phase I enzyme activities than those observed in the treated ME/B(a)P treated SHP rats. Furthermore, both ME and B(a)P significantly decreased the hepatic pool of vitamin A while a concomittant increase in that of vitamin C was observed. 相似文献
82.
The use of direct susceptibility testing from specimens has led to the fortuitous observation that penicillin-susceptible strains have larger inhibition zones for mecillinam than do β -lactamase producers. The current study was, therefore, undertaken to test 179 Staphylococcus aureus isolates for mecillinam susceptibility by Rosco Neo-Sensitabs and to compare the results with commonly used tests for β -lactamase production, i.e. size and character of penicillin inhibition zones, chromogenic cephalosporin (nitrocefin) tests and clover leaf assays. Agreement between methods was reached for 175 of 179 strains when disregarding the results of the nitrocefin tests, 88 isolates being found susceptible and 87 being found to be β -lactamase producers. All 88 susceptible isolates had mecillinam zones of >22 mm, with the great majority being >25 mm; double zones did, however, occur. The 87 β -lactamase producers had zones <14 mm or no zones. Four isolates presenting problems in had mecillinam zones of ≤20 mm and were without tapering growth at the penicillin inhibition zone edge. In conclusion, the size of the mecillinam inhibition zone is found to be a useful supplementary test in the clinically important distinction between β -lactamase-producing and non-producing isolates of S. aureus . 相似文献
83.
C.K. Biswas J.M. Ramos D.N.S. Kerr 《Clinica chimica acta; international journal of clinical chemistry》1981,116(3):343-347
The effect of heparin on plasma ionised calcium was studied by adding it in increasing amounts to whole blood from 10 normal subjects. There was no significant change in ionised calcium from the addition of 1 U/ml but a significant fall of 0.02 mmol/1 when 2 U/ml were added and a progressive further fall with increasing concentrations. Heparin from three different manufacturers produced similar results. The effect of heparinisation in vivo was studied during regular haemodialysis on 10 patients with chronic renal failure. Following intravenous injection of 10000 U of heparin there was a consistent and significant fall averaging 0.03 mmol/l. 相似文献
84.
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86.
CD117阳性小肠间质瘤中Ki67和p53蛋白的表达及在预后中的意义 总被引:5,自引:0,他引:5
目的 :研究小肠间质瘤 (smallbowelstromaltumors,SBST)Ki6 7和p5 3免疫组织化学的表达 ,探讨两者在肿瘤良恶性划分和预后中的作用。方法 :选用CD117阳性的SBST 33例进行光镜观察 ,用EnVisionTM+二步法免疫组化方法检测Ki6 7和 p5 3蛋白在肿瘤中的表达情况并与形态学进行比较。 结果 :33例SBST患者 ,男 2 0例 ,女13例 ,年龄 2 1~ 71岁 ,发生于十二指肠 5例 ,空肠 2 2例 ,回肠 6例。肿瘤最大径的范围在 1.5~ 2 0cm之间。在光镜下出现肿瘤内坏死的有 11例。肿瘤核分裂象计数每 5 0个高倍镜视野 0个有 6例 ,1~ 2个 5例 ,≥ 3个的有 2 2例。 33例中良性 4例 ,交界性 4例 ,恶性 2 5例。随访时间为 3~ 180个月 (平均 73.3个月 ) ,结果为良性组 4例均无瘤生存 ;交界性组 2例无瘤生存 ,1例失访 ,1例在无瘤生存 18个月后失访 ;恶性组无瘤生存有 7例 ,带瘤生存者及死亡有 16例 ,2例失访。Ki6 7染色阴性 2例 ,均为良性 ;其余 31例阳性中 ,增殖指数 (阳性细胞数 )大于 5 %的有恶性 16例 (94 .1% ) ,交界性 1例。在免疫组化p5 3染色中 ,恶性组 2 5例均呈阳性表达 (平均阳性细胞数 4 2 .9% ) ,其中 12例阳性细胞数大于 5 0 %。当Ki6 7和 p5 3均为阴性或两者阳性细胞数分别是 <1%和 <10 %时 ,肿瘤呈良性经过 ,预后 相似文献
87.
胃肠道肿瘤病人围手术期细胞因子及蛋白质代谢的变化 总被引:4,自引:0,他引:4
目的 :探讨胃肠道肿瘤病人手术后肿瘤坏死因子 α (TNF α)、白介素 6 (IL 6 )、白介素 10 (IL 10 )的变化以及与蛋白质代谢的关系。 方法 :用酶联免疫法 (ELISA)检测 19例胃肠道肿瘤根治术病人术前和术后 1、3、5天血清TNF α、IL 6和IL 10水平 ,同时检测蛋白质分解代谢相关指标、2 4h尿中尿素和肌酐排泄量。 结果 :胃肠道肿瘤根治术后病人TNF α呈下降趋势 ,术后第 1天较术前明显下降 (P <0 .0 5 )。IL 6和IL 10术后升高 (P <0 .0 1) ,尤以术后第 1天升高明显。术后 2 4h尿中尿素和肌酐排泄量明显升高。 结论 :胃肠道肿瘤根治术后病人IL 6和IL 10的升高支持手术应激导致的细胞因子释放变化 ,但TNF α呈下降趋势 ,可能与胃肠道肿瘤病人术前TNF α的高表达有关。术后蛋白质分解代谢增加 ,可能与细胞因子IL 6和IL 10的升高有关。 相似文献
88.
T. Brenner A. Boneh E. Shohami O. Abramsky J. Weidenfeld 《Journal of neuroimmunology》1992,40(2-3):273-279
We measured the production of two eicosanoids, prostaglandin E2 and thromboxane-B2, by rat glial cell cultures under basal conditions, following stimulation with phorbol-12-myristate-13-acetate and the bacterial endotoxin lipopolysaccharide, and following treatment with synthetic glucocorticoids. Stimulation of rat glial cells in culture with either phorbol-12-myristate-13-acetate or lipopolysaccharide caused a 1.5–5.0-fold increase in prostaglandin E2 production, but did not affect thromboxane production. Pretreatment of the cultures with dexamethasone markedly inhibited the stimulated production of prostaglandin E2 but had only a modest effect on basal production. Dexamethasone did not affect the activity of the enzyme protein kinase C, a putative regulator of eicosanoid synthesis. Our findings show that glucocorticoids have the potential to modulate central nervous system eicosanoid production particularly under conditions of stimulated production, such as inflammatory and demyelinating disorders. This mechanism may explain, at least in part, the therapeutic benefit of glucocorticoids in patients with multiple sclerosis. 相似文献
89.
Fentanyl and the interleukin-6 response to surgery 总被引:12,自引:0,他引:12
It has been suggested that large doses of opioids may suppress the interleukin-6 response to surgery. We examined the effects of the supplementation of inhalational anaesthesia with either 3 or 15 μg.kg−1 fentanyl on the circulating interleukin-6, interleukin-8, C-reactive protein, cortisol and glucose concentrations in 16 patients undergoing pelvic surgery. In both groups, surgery evoked the expected glucose, cortisol and interleukin-6 response but no increase in interleukin-8 was detected. There were no significant differences between the two groups. We conclude that the supplementation of inhalational anaesthesia with conventional doses of opioids does not modify the cytokine response to surgery. 相似文献
90.
用PCR—RFLP和16SrDNA指纹图法分析幽门螺杆菌基因型 总被引:1,自引:1,他引:0
本文建立了PCR-RFLP和16srDNA指纹图法.对19株幽门螺杆菌(HP)进行基因型分析:HP尿素酶C基因的PCR扩增产物.分别用HindⅢ、HaeⅢ、AluⅠ酶切,结果显示:每个酶均将19株HP分为3种RFLP图谱.综合HindⅢ,HaeⅢ和AluⅠ酶切结果,19株HP分为10个酶切带型;PCR扩增HP标准株16SrRNA基因,地高辛标记制备550bp探针,19株HPDNA分别经HaeⅢ和EcoRⅠ酶切、电泳后,通过Southern杂交获16SrDNA指纹图,结果显示:HaeⅢ酶切分为14个杂交带型,EcoRⅠ酶切19株HP杂交带型均不同。本实验表明:上述两种方法重复性好,分群力高,可准确有效地对HP作出鉴定并将其分型。19株HP株间存在基因型差异。 相似文献