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61.
甲状腺癌淋巴结微转移的研究 总被引:2,自引:0,他引:2
目的:探讨MUC1检测在甲状腺癌淋巴结微转移的可靠性和敏感性。方法:对488例甲状腺疾病手术患者于术前24h用1%美兰1.0~2.0mL注射于甲状腺结节或周围腺体,术中显示蓝染淋巴结,采用RT-PCR法测定临床蓝染淋巴结中的MUC1。 结果:蓝染淋巴结显示率甲状腺癌为93%,良性病例为0。研究组80个蓝染淋巴结中发现有MUC1mRNA表达的为95%,与病理诊断率(86%)相比有提高(P<0.05);良性病变(阴性对照组)淋巴结均不存在MUC1mRNA的表达;阳性对照组的癌转移性淋巴结均存在MUC1mRNA的表达。结论:MUC1较病理检查敏感,PCR产物点杂交进一步证实MUC1作为PCR标志物有较好的可靠性。 相似文献
62.
风疹易感人群婚前风疹疫苗接种预防先天性风疹综合征 总被引:1,自引:0,他引:1
目的探讨婚前风疹易感人群风疹疫苗接种在提高孕妇对风疹的免疫力,预防先天性风疹综合征中的作用.方法对10 913例婚前风疹病毒抗体IgG阴性者给予国产风疹减毒活疫苗注射.3个月随防671例,比较风疹疫苗接种前后该地区孕妇近期风疹感染的发病率.结果818例风疹病毒抗体IgG阴性者接种后抗体转阳率为99.8%.风疹疫苗接种前后3年孕妇近期风疹感染率分别为0.37%及0.08%,有明显下降,有非常显著差异(P<0.001).结论应用国产风疹减毒活疫苗对婚前易感人群作预防接种可提高育龄妇女对风疹的免疫力,降低孕期风疹感染的发生率,是预防先天性风疹综合征及风疹致畸的有效、安全措施. 相似文献
63.
《Journal of labelled compounds & radiopharmaceuticals》2003,46(6):531-537
Exposure of captodative enone systems to deuterium in the presence of Crabtree's catalyst ( 1 ) results in deuteration at the vinylic site β‐ to the ketone carbonyl, as well as at any accessible ortho‐position. β‐exchange is also observed during the reduction of ethyl cinnamate ( 3 ) catalyzed by 1 . Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
64.
川芎嗪对肾缺血再灌注时c-fos bcl-2 ICAM-1蛋白表达的影响 总被引:1,自引:0,他引:1
目的 探讨大鼠肾缺血再灌注损伤不同时间c -fos、细胞淋巴瘤 /白血病 - 2、细胞间粘附分子- 1蛋白的表达及川芎嗪对其影响。方法 用免疫组化法检测大鼠急性肾缺血再灌注不同时间内及川芎嗪干预后c -fos、细胞淋巴瘤 /白血病 - 2、细胞间粘附分子 - 1蛋白表达的分布及强度变化。结果 c -fos蛋白分布于近曲小管、远曲小管、集合管上皮细胞的细胞核、细胞浆内 ,再灌注后 1h表达明显增强 ,3h达高峰 ,6h锐减。细胞淋巴瘤 /白血病 - 2蛋白主要分布于近曲小管上皮细胞的细胞浆 ,再灌注后 1h表达明显增强 ,6h达高峰 ,2 4h仍有较强表达。细胞间粘附分子 - 1蛋白分布在肾血管、肾小管等部位 ,其中以肾血管为著 ,其表达增强于再灌注后 1h ,直到 2 4h仍有增高趋势。川芎嗪干预后c -fos、细胞间粘附分子 - 1蛋白表达明显下降 (P <0 0 1 )。细胞淋巴瘤 /白血病 - 2表达明显增高 (P <0 .0 1 )。结论 川芎嗪对肾缺血再灌注损伤有较好的保护作用 相似文献
65.
Christian J. Sauder Cheryl X. Zhang Malen A. Link W. Paul Duprex Kathryn M. Carbone Steven A. Rubin 《Vaccine》2009
The recent global resurgence of mumps has drawn attention to the continued need for robust mumps immunization programs. Unfortunately, some vaccines derived from inadequately attenuated vaccine strains of mumps virus have caused meningitis in vaccinees, leading to withdrawal of certain vaccine strains from the market, public resistance to vaccination, or in some cases, cessation of national mumps vaccination programs. The most widely implicated mumps vaccine in cases of postvaccination meningitis is derived from the Urabe AM9 strain, which remains in use in some countries. The Urabe AM9 vaccine virus has been shown to exhibit a considerable degree of nucleotide and amino acid heterogeneity. Some studies have specifically implicated variants containing a lysine residue at amino acid position 335 in the hemagglutinin-neuraminidase (HN) protein with neurotoxicity, whereas a glutamic acid residue at this position was associated with attenuation. To test this hypothesis we generated two modified Urabe AM9 cDNA clones coding either for a lysine or a glutamic acid at position 335 in the HN gene. The two viruses were rescued by reverse genetics and characterized in vitro and in vivo. Both viruses exhibited similar growth kinetics in neuronal and non-neuronal cell lines and were of similar neurotoxicity when tested in rats, suggesting that amino acid 335 is not a crucial determinant of Urabe AM9 growth or neurovirulence. 相似文献
66.
Moussa Ndong Machiko Kazami Tsukasa Suzuki Mariko Uehara Shin-ichi Katsumata Hirohumi Inoue Ken-Ichi Kobayashi Tadahiro Tadokoro Kazuharu Suzuki Yuji Yamamoto 《Nutrition Research》2009,29(9):640-647
Iron deficiency (ID) is one of the most commonly known forms of nutritional deficiencies. Low body iron is thought to induce neurologic defects but may also play a protective role against cancer development by cell growth arrest. Thus, ID may affect cellular pathways controlling cell growth and proliferation, the mechanism of which is still not fully understood. The serine/threonine protein kinase Akt and its downstream target, the mammalian Target of Rapamycin (mTOR), is known to play a crucial role in the regulation of cell growth and survival. Therefore, we hypothesized that Akt/mTOR pathway could be influenced by ID. Three-week-old male Wistar-strain rats were divided into 3 groups and the 2 groups had free access to a control diet (C group) or an iron-deficient diet (D group). The third group (PF group) were pair-fed the control diet to the mean intake of the D group. After 4 weeks, rats were killed and their brains were sampled. In separate experiments, COS-1 cells were cultured with or without the iron chelator deferoxamine. Western blots of brain samples and COS-1 lysates were used to analyze the expression and phosphorylation state of Akt, TSC2, mTOR, and S6 kinase proteins implicated in the Akt/mTOR pathway. Using 2 different ID models, we show for the first time that iron deficiency depresses Akt activity in rats and in COS-1 cells, leading to a decrease in mTOR activity. 相似文献
67.
Chandipura virus (CHPV) has emerged as an important pediatric encephalitis-causing pathogen with very high mortality in India. No specific vaccine or treatment is available till date. We attempted to prepare a candidate vaccine employing recombinant CHPV Glycoprotein (rGp). The Glycoprotein gene (G-gene) of CHPV was expressed using Baculovirus expression system. The rGp was purified by HPLC and used for mice immunization, 3 doses, and 4 weeks apart. One microgram rGp was found to be optimum. Sero-conversion was observed as early as 2nd week by detecting anti-CHPV IgG antibodies. Antibody titres were immunogen-concentration dependent. Intracerebral challenge of the immunized mice with 100 LD50 of the homologous strain demonstrated 90% protection. In in vitro neutralization, antibodies from the immunized mice were able to neutralize heterologous viruses. There was 60% T cell proliferation observed against rGp in immunized mice. The study shows that rGp induces both arms of immune response and represents an ideal vaccine candidate for further evaluations. 相似文献
68.
目的 研究藏药抱茎獐牙菜Swertia franchetiana中的苷类成分。方法 用各种柱色谱方法进行分离纯化,根据理化性质和波谱解析鉴定其化学结构。结果 从抱茎獐牙菜的水溶性部分得到11个化合物,分别鉴定为芒果苷(mangiferin,Ⅰ)、异荭草苷(isoorlentin,Ⅱ)、当药黄素(swertisin,Ⅲ)、当药醇苷(swertianolin,Ⅳ)、1-羟基-3,5-二甲氧基汕酮-1-O-[β-D-吡喃木糖(1→6)-β-D-吡喃葡萄糖(Ⅴ)、1-羟基一3,7,8-三甲氧基汕酮-1-O-[β-D-吡喃葡萄糖(Ⅵ)、1-羟基-2,3,5-三甲氧基汕酮-1-O-[β-D-吡喃木糖(1→6)-β-D-吡喃葡萄糖(Ⅶ)、5-醛基1-异色满酮(Ⅶ)、獐牙菜苦苷(swartiamarin,Ⅸ)、龙胆苦苷(gentipicroside,Ⅹ)和獐牙菜苷(sweroside,Ⅺ)。结论 化合物Ⅵ~Ⅺ均为首次从该植物中得到,其中Ⅶ为首次从獐牙菜属植物中得到。 相似文献
69.
目的:探讨异丙酚和芬太尼混合液静脉麻醉、笑气吸入麻醉及2%利多卡因宫颈局部浸润麻醉三种镇痛方法在人工流产手术中的疗效比较。方法:自2003年8月至2004年1月对236例妇科门诊早孕要求终止妊娠的妇女实施无痛人工流产术。随机分成3组。A组:异丙酚+芬太尼静脉麻醉(85例);B组:N2O(笑气)吸入麻醉(88例);C组:2%利多卡因宫颈局部浸润麻醉(63例),观察人流术中其镇痛效果并对疼痛进行分级。结果:A组85例100%可达到完全不痛(疼痛分级为0级);B组65.90%可达到完全不痛,Ⅰ级23.86%,Ⅱ级9.09%,Ⅲ级1.15%;C组0例可达到完全不痛,Ⅰ级63.49%,Ⅱ级30.16%,Ⅲ级6.35%。结论:受术者如无心肺疾患及人流禁忌证,无痛人工流产术应选择异丙酚+芬太尼静脉麻醉可达到完全无痛,痛苦最小。 相似文献
70.
Relaxin down-regulates renal fibroblast function and promotes matrix remodelling in vitro. 总被引:1,自引:0,他引:1
Rosemary Masterson Tim D Hewitson Kristen Kelynack Marina Martic Laura Parry Ross Bathgate Ian Darby Gavin Becker 《Nephrology, dialysis, transplantation》2004,19(3):544-552
BACKGROUND: Renal fibroblasts are important effector cells in tubulointerstitial fibrosis, with experimental antifibrotic strategies focusing on the functional down-regulation of these cells. Several experimental models of fibrosis have provided evidence for the effectiveness of the polypeptide hormone relaxin as a potential antifibrotic agent. This study was conducted to further elucidate the antifibrotic mechanisms of relaxin on renal fibroblasts in vitro. METHODS: Rat cortical fibroblasts were obtained from outgrowth culture of renal tissue isolated from kidneys 3 days post-unilateral ureteric obstruction and constituted 100% of cells studied. A relaxin radio-receptor assay was used to establish binding of relaxin to renal fibroblasts in vitro. Functional studies then examined the effects of H2 relaxin (0, 1, 10 and 100 ng/ml) on fibroblast kinetics, expression of alpha-smooth muscle actin (alpha-SMA), total collagen synthesis, collagenase production and collagen-I lattice contraction. CTGF mRNA expression was also measured by northern analysis. RESULTS: H2 relaxin bound with high affinity to rat renal fibroblasts, but receptor numbers were low. Consistent with its previously reported bimodal effect, transforming growth factor (TGF-beta 1) reduced fibroblast proliferation, an effect abrogated by H2 relaxin. Fibroblasts exposed to H2 relaxin (100 ng/ml) for 24 h demonstrated decreased immunostaining for alpha-SMA and reduced alpha-SMA protein expression compared with controls. There was a trend for a relaxin-mediated reduction in total collagen synthesis and alpha 1(I) mRNA expression with large dose-related increases in collagenase protein expression being observed. TGF-beta 1-stimulated collagen-I lattice contraction was significantly inhibited following co-incubation with 100 ng/ml relaxin. Incremental doses of H2 relaxin had no significant effect on CTGF mRNA expression. CONCLUSIONS: The findings of this study suggest that the antifibrotic effects of relaxin involve down-regulation of fibroblast activity, increase in collagenase synthesis and restructuring of collagen-I lattices, which are consistent with its known physiological role of matrix remodelling. Although there appears to be an interaction between TGF-beta 1 and H2 relaxin, this does not appear to involve a reduction in CTGF mRNA expression. 相似文献