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991.
Recently, we and others showed that the components of green tea may be useful cancer chemopreventive agents. It has been suggested that (-)-epigallocatechin-3-gallate (EGCG), the major constituent in green tea, may possess antitumor-promoting and/or anticarcinogenic effects in rodent tumor bioassay systems. During the chemical analysis of various green tea products, we found a traditionally preserved preparation of green tea used by tribes in the Himalayan region of Sikkim, India that was rich in EGCG. EGCG was isolated from this tea product, and its inhibitory effects were evaluated against the binding of topically applied 3H-labeled polycyclic aromatic hydrocarbons (PAHs) to epidermal DNA and 12-O-tetradecanoylphorbol-13-acetate (TPA) caused induction of epidermal ornithine decarboxylase (ODC) activity in Sencar mice, the short-term markers of tumor initiation and tumor promotion, respectively. Preapplication of EGCG resulted in significant inhibition (p less than 0.05) in the binding of [3H]PAH to epidermal DNA. Similarly, the topical application of EGCG resulted in significant inhibition (p less than 0.005) in TPA-caused induction of epidermal ODC activity. In further studies, we assessed the anti-skin tumor-initiating effect of EGCG in Sencar mice in an initiation-promotion protocol. The application of EGCG before challenge with 7,12-dimethylbenz[a]anthracene as tumor initiator resulted in significant reduction both in percentage of mice with tumors and number of tumors per mouse compared with a non-EGCG-pretreated group of animals. The results of the present study suggest that the green tea preparation from Sikkim may be a good source for the isolation of EGCG and that this compound may have significant potential as a cancer chemopreventive agent. 相似文献
992.
Yang-Chyuan Chang Ching-Ying Yeh Jung-Der Wang 《American journal of industrial medicine》1995,27(2):271-279
Pattern visual, brainstem auditory, and somatosensory evoked potential (EP) studies were performed on 26 chloralkali workers. The intensity of mercury vapor exposure in these workers was estimated from the individual working history. Mercury levels in blood, urine, and hair were determined with atomic absorption spectrometry. The EP findings were compared with those from individually matched normal subjects. In brainstem auditory and somatosensory EP studies, prolonged neural conduction times in the central nervous system (CNS) were found in workers exposed to mercury vapor. In the pattern visual EP study, mercury workers had higher interpeak amplitudes. Findings of this study suggested that chronic exposure to mercury vapor would affect the CNS functions. A multimodality EP study is a useful adjunct in evaluation of chronic mercury neurotoxicity, especially in an epidemiological study. 相似文献
993.
应用抗猪囊虫抗原的单克隆抗体反向间接血凝试验(IHAT),对临床确诊的囊虫病患者进行了血清循环抗原(CAg)的检测,阳性率为51.14%(67/131)。对19例脑型囊虫病患者同时测定了血清和脑脊液中的CAg,阳性率分别为47.36%和78.94%,总阳性率为84.21%。对治疗0.53后的19例患者检测时,血清和脑脊液中CAg均呈阴性反应,而检测抗体仍呈阳性反应。50例正常人、49例其它寄生虫病及5例其它脑部疾病患者脑脊液的CAg均呈阴性反应。结果提示:测定CAg对囊虫病活动性感染的诊断及疗效判定均具有一定的实用价值。 相似文献
994.
Songlin Wang DDS PhD Zhaoju Zou DDS FICD Qiquang Wu DDS Kaihua Sun DDS 《Journal of oral and maxillofacial surgery》1992,50(12):1332-1333
Most cases with recurrent parotitis in childhood (RPC) can be cured before puberty.1–3 A few of them, however, may continue to adulthood.1–4 To distinguish this condition from other types of chronic parotitis in adults, such as chronic obstructive parotitis,5 we suggest that the diagnosis of recurrent parotitis in adults (RPA) be reserved for the cases derived from RPC.6 The pathophysiology and development of RPA is still not well known. To our knowledge, there are few reports of RPA in the literature, especially concerning its histopathology. This report describes a cases of RPA studied with sialography and light and electron microscopy. 相似文献
995.
996.
在体肺隔离高温灌注的实验研究 总被引:1,自引:0,他引:1
8条犬于左肺动脉及左房分别插入灌注管及引流管后阻断,使左肺隔离。肝素化预充液中加入超量阿霉素进行常温及高温(41~43℃)的灌注转流。监测肺水含量、肺顺应性、血气、肺动脉压、肺实质温度、鼻咽温、血液学等指标,并行病理检查。结果表明:单侧肺隔离高温灌注在手术方法与转流技术上是可行的;它提供的热源简便,温度理想。高温灌注化疗对肺组织有一定影响,但其程度可逆;临床应用是可行的。 相似文献
997.
The extraction, purification, pharmacological experiments and chemical analysis of anti-hepatoma active principles of Radix Aconiti Kusnezoffii have been studied. The results show that the medicinal material Radix Aconiti Kusnezoffii is efficacious in inhibiting hepatoma, and the active principles are mainly made up of poisonous ester alkaloids. The liver targeting delivery system will be the first choice for its anti-hepatoma preparation, and the effective component AY3a is fit for the preparation of targeted microspheres. 相似文献
998.
为探讨脑组织移植治疗脑损伤及供体组织的保存,作者在制造大鼠运动区皮层损伤的基础上,分别以新鲜及Iloprost液或生理盐水保存3小时的胎鼠歧层组织为供体,将其移植到损的大鼠中,观察移植后的神经行为变化及形态学改变。 相似文献
999.
心导纳微分环,肺导纳微分环最大向量正常值及其临床意义 总被引:2,自引:0,他引:2
本文报道3-50岁214例心导纳微分环(CADL)和肺导纳微分环(PADL)最大向量振幅及方位正常值,结果随增龄变化振幅递减,方位递增,多数男>女,部分组间有差异。48例左向右分流先心病环体最大向量与肺动脉压之间呈平行关系,并探讨其临床意义。 相似文献
1000.