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991.
苯DNA加合物研究进展(综述)李桂兰,常平综述徐伯洪审校(中国预防医学科学院劳动卫生与职业病研究所,北京100050)我国职业接触苯的工人约有50万,长期接触苯可引起白血病。苯与其它实质性肿瘤的问题也有报道[1,2]。世界癌症研究机构(IARC)19... 相似文献
992.
993.
风湿性心脏病二尖瓣置换术中细胞因子水平的变化 总被引:1,自引:0,他引:1
目的测定风湿性心脏病二尖瓣置换术中细胞因子水平,了解它们的变化规律。方法 11例体外循环(CPB)下二尖瓣置换术患者,分别于术前,主动脉阻断前,主动脉阻断后5min,主动脉开放后10min、1h、2h、4h、24h测定白介素6(IL-6)、白介素8(IL-8)、白介素10(IL-10)以及肿瘤坏死因子(TNF)。结果IL-6、IL-8、IL-10水平在CPB开始后逐渐升高,在主动脉开放后2h左右达到高峰(P<0.01)。之后逐渐下降,到主动脉开放后24h已显著下降。TNF水平在CPB开始后逐渐升高,在主动脉开放后24h仍维持在很高的水平(P<0.01)。结论CPB下二尖瓣置换术中既有促炎因子水平的升高,又有抗炎因子的激活。 相似文献
994.
目的 探讨可溶性白细胞介素 2受体 (sIL 2R)和可溶性白细胞介素 6受体 (sIL 6R)在多发性硬化(MS)发病过程中的作用。方法 采用双体夹心ELISA法对 2 9例MS急性期患者及 2 0例炎性神经病患者、39例非炎性神经病患者、2 0例健康对照者脑脊液和血清中sIL 2R和sIL 6R的含量进行检测。结果 MS患者血清和脑脊液中sIL 2R、sIL 6R含量明显高于非炎性神经病组 (P <0 .0 5 )及健康对照组 (P <0 .0 1) ;MS组sIL 2R和血清sIL 6R含量与炎性神经病组比较 ,无显著性差异 ,但脑脊液中sIL 6R水平明显低于炎性神经病组 (P <0 .0 1)。结论 sIL 2R和sIL 6R在MS急性期患者体内明显升高 ,进一步证实了MS有关免疫学的发病机制 ,并为临床诊断MS提供了具有参考价值的实验室指标 相似文献
995.
杀菌性通透性增强蛋白对失血性休克的保护作用及其机理 总被引:2,自引:0,他引:2
分别在失血和复苏开始即刻iv杀菌性/通透性增强蛋白(BPI)1.5和3.5mgkg-1,观察BPI对大鼠失血性休克转归的影响.结果显示,BPI治疗能明显改善失血性休克大鼠肝肾功能,提高休克动物存活率(BPI组81%vs休克对照组44%,P<0.05),BPI组大鼠复苏后与休克前的血浆内毒素(0.20±0.04vs0.24±0.05kUL-1)水平无明显变化,血浆肿瘤坏死因子α和白介素6水平较休克前明显升高,但均显著低于休克对照组.提示BPI对失血性休克大鼠具有一定的保护作用,其机理可能与BPI拮抗休克时内源性内毒素活性,抑制细胞因子反应有关. 相似文献
996.
中国人丙型肝炎病毒囊膜蛋白2HVR1 cDNA的序列分析 总被引:1,自引:0,他引:1
目的:了解中国HCV流行株高变区1(HVR1)的特点。方法:对来自山东(SD)、上海(SH)两地患者血清RNA进行逆转录-巢式PCR,扩增HCV囊膜蛋白2基因片段,用PCR直接测序法对该片段进行序列测定。结果:(1)扩增片段(命名为P388)对应于日本HCV-J株序列核苷酸1439 ̄1826位(氨基酸位371 ̄498);(2)中国人HCV HVR1位于氨基酸位384 ̄410,与发表的HCVⅡ型HV 相似文献
997.
Gen Matsuo Yasuo Matsumura Kiyoshi Tadano Takashi Hashimoto Shiro Morimoto 《Clinical and experimental pharmacology & physiology》1997,24(7):487-491
1. The effects of sarafotoxin S6c (S6c), a selective endothelin ETB receptor agonist, on renal haemodynamics and urine formation were examined in anaesthetized dogs. 2. Intrarenal arterial infusion of S6c at a rate of 1 or 5 ng/kg per min produced a transient increase in renal blood flow (RBF), with no change in systemic blood pressure and heart rate; RBF then decreased gradually to below the basal value. There were significant and dose-dependent increases in urine flow and free water clearance and decreases in urine osmolality during S6c infusion, whereas urinary excretion of sodium and glomerular filtration rate (GFR) remained unchanged. Simultaneously, S6c administration elicited a marked increase in urinary excretion of nitric oxide (NO) metabolites, N02? and N03? (UNO*V). 3. In dogs simultaneously administered S6c (5 ng/kg per min) and iVG-nitro-L-arginine (NOARG; 40 (jig/kg per min), a NO synthase inhibitor, the renal vasodilator effect of S6c was abolished and marked reductions in RBF and GFR were observed. The S6c-induced diuretic action was not affected by NOARG. In the presence of NOARG, there was a small amount of UNOxV at the basal level and the administration of S6c did not increase UNOxV. 4. These results suggest that an intrarenal arterial infusion of S6c enhances the production of NO in the kidney and that this enhancement contributes to the peptide-induced renal vasodilation. In contrast, it is unlikely that S6c-induced water diuresis is related to NO production stimulated by this peptide. 相似文献
998.
Previous study has shown that α2D-adrenoceptors are involved in modulation of peristalsis in the rat ileum. The aim of the present study was to determine the
tissue location of α-adrenoceptors in the rat ileum by using a recently devised method. The pre-synaptic α-adrenoceptors were
characterised by measuring the potencies of agonists to inhibit transmurally-evoked (1 ms pulses, 10 Hz, 8-10 s trains) contractions
of the longitudinal and circular muscles and the affinities of antagonists. Post synaptic α-adrenoceptors were identified
by screening agonists and antagonists in carbachol-contracted tissues. In the circular muscle the order of potencies for inhibiting
transmurally-induced contraction was: clonidine ≥ oxymetazoline ≥ UK 14,304 ≥ guanfacine > talipexole > phenylephrine > azepexole.
The potency ratios relative to clonidine correlated to those previously derived using the rat ileum peristaltic reflex preparation.
Most of the α-adrenoceptor agonists, however, caused only small inhibitions of the longitudinal muscle contraction in response
to transmural stimulation, except phenylephrine and azepexole. RX 821002, yohimbine, rauwolscine, BRL 44408, phentolamine,
idazoxan, ARC 239, and prazosin inhibited the effect of clonidine on the circular muscle response with apparent pKB values best correlated with pKB or pKi values derived from the rat ileum peristaltic reflex preparation and other tissues known to have the α2D-subtype. The rank order of potencies at inhibiting carbachol-induced responses of both muscle layers was: phenylephrine ≥
oxymetazoline > clonidine ≥ talipexole > azepexole >> guanfacine. UK 14,304 was inactive up to 10 μM. The EC50 value of each agonist on the longitudinal muscle was not significantly different to the corresponding value on the circular
muscle. Prazosin was more potent than yohimbine at inhibiting the relaxant effect of phenylephrine in both muscle layers of
carbachol-contracted tissues. It is concluded that the recently identified α2D-adrenoceptors of the rat ileum are located on cholinergic neurons controlling circular muscle contraction. The study also
demonstrated the presence of postsynaptic α1-adrenoceptors involved in mediating relaxation in both muscle layers.
Received: 4 November 1996 / Accepted: 10 April 1997 相似文献
999.
评价酶联免疫检测血清CYFRA21—1对非小细胞肺癌的诊断价值 总被引:8,自引:0,他引:8
目的评价检测CYFRA21┐1对非小细胞肺癌的诊断价值。方法用ELISA法测定70例肺癌(LC)其中47例非小细胞肺癌(NSCLC),3例小细胞肺癌(SCLC)和20例未分型肺癌、64例肺部良性疾病患者及40例健康人血清CYFRA21┐1浓度。试验的诊断性能用相对操作特征(ROC)分析法估测之。结果测得全阈诊断准确率(OveralDiag┐nosticAccuracies)LC为0.75、NSCLC为0.76,SQC为0.83,ADE为0.67和SCLC为0.38。在相应于特异性为0.95的界定值3.47μg/L处,各型的灵敏度分别为SQC0.62,LC0.53,NSCLC0.51,ADE0.48和SCLC0.00。结论结果显示CYFRA21┐1是NSCLC较灵敏和特异的一个标志物。未观察到TNM各期间该标志物的平均水平有明显的差异;然而异常升高水平的患者的比例随病期的进展而显著增加,提示一系列检测CYFRA21┐1水平可能有助于监查NSCLC患者的疗效。 相似文献
1000.
Individuals identified in the Swedish neonatal α1 -antitrypsin (AAT) screening study were followed prospectively from their first to their eighteenth year of life. The aim of this study was to analyse the effect of environmental factors, i.e. active and passive smoking, and of clinical factors on lung function and the occurrence of respiratory symptoms in AAT-deficient adolescents. The study group consisted of 88 protease inhibitor (Pi)ZZ and 40 PiSZ adolescents. Medical history including respiratory symptoms, and active and passive smoking were recorded at each follow-up up to the age of 18 y. Lung function tests were performed at the present check-up. At the age of 18 y, both forced expiratory volume in one second (FEV1 ) and FEV1 /vital capacity (VC) were significantly lower in the smoking than in the non-smoking subgroup, and significantly more smokers than non-smokers reported the presence of phlegm. The mean FEV1 /VC ratio was lower for those presently exposed to parental smoking. Multiple linear regression analysis indicated that clinical liver disease in early life, active smoking and parental smoking were independent determinants of FEV1 /VC. The results suggest that marginal deviations in lung function and the symptom of phlegm among AAT-deficient adolescents occur characteristically early in the subgroup of smokers. Parental smoking may contribute to decreased lung function 相似文献