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91.
S. B. Rawal M. V. Singh A. K. Tyagi B. N. Chaudhuri 《European journal of nuclear medicine and molecular imaging》1993,20(1):16-19
In the present investigation thyroidal accumulation of radioiodine and its release were assessed by direct testing of thyroid function using radioactive iodine, in vivo, in sea level residents intermittently exposed to hypobaric hypoxia. Thyroidal accumulation of radioiodine and its turnover were examined daily for 14 days. Twelve healthy human male volunteers were divided into three groups, with an equal number of individuals in each group. A decompression chamber was used to expose each group of subjects to hypoxic conditions at a simulated altitude of 3810 m for 8 h/day for 14 days. An oral dose of 25Ci iodine-131 was administered to each individual of the first group immediately before the initiation of intermittent hypoxia. The second group of subjects received a tracer dose at the beginning of the 4th day of the 14 days, intermittent exposure to hypoxia, while the third group received the tracer dose 1 week after the completion of the exposure. Control studies were carried out on the subjects before they were subjected to the experimental conditions. Thyroidal accumulation of131I in experimental subjects during the hypoxic state and in the post-hypoxic state was higher than in the control studies. The pattern of accumulation during exposure to hypoxia and in the post-hypoxic state showed multiple peaks of radioactive iodine uptake (PRAIU), a unique feature. The multiple PRAIU by the thyroid in experimental subjects were sharp and of short duration, reflecting an increased rate of13I release from the thyroid. Control subjects had a single PRAIU by the thyroid 24 h after the administration of tracer. 相似文献
92.
Interactions of halogenated industrial chemicals with transthyretin and effects on thyroid hormone levels in vivo 总被引:2,自引:0,他引:2
Van den Berg K. J. van Raaij J. A. G. M. Bragt P. C. Notten W. R. F. 《Archives of toxicology》1991,65(1):15-19
Previous results in experimental systems have suggested that hydroxylated PCBs may decrease thyroid hormone levels through associative interaction with transthyretin. In the present paper it was investigated whether this property was also shared by various industrial chemicals, mainly pesticides. In total, 65 compounds from 12 chemical groups were analyzed for direct interference with the T4 binding site of transthyretin using a competitive binding assay. Sixty per cent of the compounds were competitive at a concentration level of 100 M. Relatively strong interactions were observed by several chlorophenols, chlorophenoxy acids and nitrophenols, as well as by individual compounds such as hexachlorobenzene, dicofol, bromoxynil and tetrachlorohydroquinone. Examples from these chemical groups, e.g. pentachlorophenol, 2,4-dichlorophenoxybutyric acid, dinoseb and bromoxynil, also reduced plasma TT4 levels in rats. In addition, bromoxynil decreased plasma TT3 levels. The results suggest the existence of a number of halogenated industrial chemicals with a potential for lowering plasma thyroid hormone levels through interference with hormone transport carriers. 相似文献
93.
孕母患自身免疫性甲状腺疾病对新生儿出生体重及甲状腺功能的影响 总被引:5,自引:0,他引:5
目的 探讨孕母患自身免疫性甲状腺疾病对新生儿出生体重及甲状腺功能的影响。方法 通过浙江省新生儿疾病筛查网络系统 ,自 1999年 8月至 2 0 0 2年 6月对 12 2例母亲患有自身免疫性甲状腺疾病的新生儿出生体重、甲状腺功能进行追踪观察。结果 (1)格雷夫斯病母亲的新生儿出生体重为 (32 2 4 4± 330 2 )g ,明显低于健康母亲及慢性淋巴细胞性甲状腺炎母亲的新生儿 ;(2 ) 12 2例新生儿中 ,甲状腺功能正常 97例 ,暂时性促甲状腺激素 (TSH)升高 2 1例 ,先天性甲状腺功能减低症 3例 ,甲状腺功能亢进症 1例 ,与同期健康母亲的新生儿相比有显著差异 (P <0 0 1) ,且 4例甲状腺功能异常的新生儿 ,其母亲妊娠期甲状腺功能均不正常。结论 孕母患自身免疫性甲状腺炎 ,尤为妊娠期甲状腺功能不正常对新生儿出生体重及甲状腺功能影响较大 ,加强对患自身免疫性甲状腺疾病的母亲及其孩子的管理十分重要。 相似文献
94.
95.
危重病人血清甲状腺激素的变化及其与APACHEⅡ评分和预后的关系 总被引:3,自引:0,他引:3
目的 探讨危重病人血清甲状腺激素水平的变化及其与APACHE Ⅱ评分和危重病预后的关系。方法 应用放射免疫分析法及免疫放射分析法测定危重病人的血清甲状腺激素含量。危重病程度按APCHE Ⅱ评分系统进行评分。结果 危重病人的血清TT3、TT4、FT3、FT4含量明显低于正常对照组(P<0.001),而TSH的变化无显著性(P>0.05);危重病存活组与死亡组血清甲状腺激素之间的差异无显著性(P>0.05);不同APACHE Ⅱ评分分段下危重病人的血清甲状腺激素水平比较差异无显著性(P>0.05);而危重病人死亡组的APACHE Ⅱ评分明显高于存活组的APACHE Ⅱ评分(P<0.001)。结论 非甲状腺疾病的危重病人常出现甲状腺功能指标异常。血清甲状腺激素的变化不能作为判断病情的严重程度及评估预后的指标。而APACHEⅡ评分系统适用于危重病人严重程度及评估预后的评估。 相似文献
96.
目的 应用抑制性消减杂交技术,构建人甲状腺癌与正常甲状腺差异表达的cDNA消减文库。方法 分别从甲状腺癌及正常甲状腺组织中提取总RNA,应用高效、灵敏的抑制性消减杂交技术,构建成功cDNA消减文库,再转染大肠杆菌进行文库扩增。结果 构建成功具有高消减效率的人甲状腺癌组织cDNA消减文库,文库扩增得到了400个克隆,随机挑取50个制备质粒,酶切分析均得到50bp-400bp大小插入片段,这些片段可能就是载有高度特异性的目的片段。结论 人甲状腺癌组织cDNA消减文库的建立为进一步克隆甲状腺癌特异性表达的新基因奠定了基础。 相似文献
97.
甲状腺乳头状癌MMP-2、MMP-9、TIMP-1和TIMP-2表达对肿瘤侵袭转移的影响 总被引:3,自引:1,他引:3
目的 研究甲状腺乳头状癌基质金属蛋白酶 2 ,9(MMP 2 ,MMP 9)及其组织基质蛋白抑制剂 1,2 (TIMP 1,TIMP 2 )表达对肿瘤侵袭转移的影响。方法 采用免疫组织化学S P法 ,检测 65例甲状腺乳头状癌组织中MMP 2、MMP 9、TIMP 1和TIMP 2的表达。结果 MMP 2、MMP 9、TIMP 1和TIMP 2在甲状腺乳头状癌组织中的阳性表达率分别为 76.9%、87.7%、76.9%和 61.5 %。MMP 2和MMP 9表达与淋巴结转移和肿瘤侵袭程度呈正相关 (P <0 .0 1,P <0 .0 5 )。TIMP 1表达与淋巴结转移和侵袭程度呈负相关 (P <0 .0 5 )。TIMP 2表达与淋巴结转移呈负相关 (P <0 .0 5 ) ,与侵袭程度无明显相关性。MMP 9与TIMP 1表达有显著相关性 ,且呈负相关 (P <0 .0 1)。结论 MMP 2、MMP 9、TIMP 1和TIMP 2表达与甲状腺乳头状癌的侵袭转移密切相关 ,是临床判断甲状腺乳头状癌转移有价值的参考指标 相似文献
98.
Management of papillary microcarcinoma of the thyroid gland 总被引:5,自引:0,他引:5
E. Orsenigo E. Beretta E. Fiacco F. Scaltrini P. Veronesi L. Invernizzi P. Gini P. Fiorina V. Di Carlo 《European journal of surgical oncology》2004,30(10):1104-1106
DESIGN: To investigate the frequency, treatment and clinical behaviour of differentiated microcarcinoma of the thyroid gland (PTMC). PATIENTS AND METHODS: Out of 376 patients submitted to surgical treatment for differentiated thyroid cancer from June 1980 to October 2003, 77 had been identified has having a PTMC (63 females, 14 males; mean age 43+/-13 years). Sixty-seven patients (87%) met the AMES risk definition for low (group I) and 10 (13%) for high-risk (group II) definition. The surgical procedures were lobo-isthmusectomy (n=14) or subtotal thyroidectomy (n=20) and total thyroidectomy (n=43) with node dissection in 15 cases. Follow-up ranging from 9 to 274 months (mean 124+/-84). RESULTS: Overall patient survival rates were 100 and 94% at 20 years in groups I and II, respectively (p=ns). There were no significant differences in surgical complications and in survival in patients submitted to total thyroidectomy when compared to partial thyroid resection. The presence of cervical node metastasis did not affect patient survival (p=0.8). The overall mean survival time was 266 months. CONCLUSIONS: Despite the overall excellent prognosis, PTMC was associated with a 1% disease-related mortality, a 2.5% local recurrence rate, 1% lymph-node recurrence rate, and 1% distant metastasis rate. We recommend total thyroidectomy accompanied by modified neck dissection if enlarged nodes are diagnosed. 相似文献
99.
100.
胸骨后甲状腺肿物的手术处理 总被引:1,自引:0,他引:1
为探讨胸骨后甲状腺肿物手术切除的进路方式,回顾性分析30年来外科治疗的结果。1965年至1994年间全部患者共87例,其中结节性甲状腺肿64例,占73.6%;甲状腺腺瘤13例,占14.9%;甲状腺恶性肿瘤10例,占11.5%。通过颈部入路手术切除的占70%(61/87),胸骨正中劈开切除的占16%(14/87),前切口开胸切除的占14%(12/87)。随着经验的积累,除误诊为纵隔其它来源的肿物外,1980年以后已不再行前切口开胸手术切除,1985年以后的43例中,只有1例胸骨后结节性甲状腺肿的患者行胸骨劈开手术,其余均从颈部入路手术。由于颈部入路相对并发症少、损伤小、安全可靠,建议对良性的胸骨后甲状腺肿物和部分恶性肿物行颈部衣领式切口手术。 相似文献