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1.
目的 研究异型增生程度不同的口腔白斑和不同分级的鳞癌中谷胱苷肽S转移酶π(GST π)的表达 ,探讨GST π在口腔鳞癌发生发展中的作用。 方法 采用免疫S -P法 ,对 5 4例轻、中、重度异型增生 ,4 7例高、中、低分化的口腔鳞癌 ,7例口腔粘膜上皮单纯增生患者组织进行GST π检测。 结果 口腔粘膜上皮单纯增生组织中未见GST π的表达 ,轻、中、重度异型增生病例中的GST π阳性率分别为4 7.8%、5 2 .9%和 6 4 .2 % ,高于单纯增生组 (P <0 .0 1) ;高分化鳞癌GST π阳性率为 6 4 .7% ,中、低分化鳞癌组分别为 2 8.5 %及 2 2 .2 % ,中、低分化鳞癌组表达均低于高分化鳞癌组及异型增生组 (P <0 .0 5 )。 结论 GST π表达的变化与口腔鳞癌早期的发生发展密切相关 相似文献
2.
Abstract: Native chemical ligation has proven to be a powerful method for the synthesis of small proteins and the semisynthesis of larger ones. The essential synthetic intermediates, which are C‐terminal peptide thioesters, cannot survive the repetitive piperidine deprotection steps of Nα‐9‐fluorenylmethoxycarbonyl (Fmoc) chemistry. Therefore, peptide scientists who prefer to not use Nα‐t‐butyloxycarbonyl (Boc) chemistry need to adopt more esoteric strategies and tactics in order to integrate ligation approaches with Fmoc chemistry. In the present work, side‐chain and backbone anchoring strategies have been used to prepare the required suitably (partially) protected and/or activated peptide intermediates spanning the length of bovine pancreatic trypsin inhibitor (BPTI). Three separate strategies for managing the critical N‐terminal cysteine residue have been developed: (i) incorporation of Nα‐9‐fluorenylmethoxycarbonyl‐S‐(N‐methyl‐N‐phenylcarbamoyl)sulfenylcysteine [Fmoc‐Cys(Snm)‐OH], allowing creation of an otherwise fully protected resin‐bound intermediate with N‐terminal free Cys; (ii) incorporation of Nα‐9‐fluorenylmethoxycarbonyl‐S‐triphenylmethylcysteine [Fmoc‐Cys(Trt)‐OH], generating a stable Fmoc‐Cys(H)‐peptide upon acidolytic cleavage; and (iii) incorporation of Nα‐t‐butyloxycarbonyl‐S‐fluorenylmethylcysteine [Boc‐Cys(Fm)‐OH], generating a stable H‐Cys(Fm)‐peptide upon cleavage. In separate stages of these strategies, thioesters are established at the C‐termini by selective deprotection and coupling steps carried out while peptides remain bound to the supports. Pilot native chemical ligations were pursued directly on‐resin, as well as in solution after cleavage/purification. 相似文献
3.
TERUAKI HONGO CHIEKO WATANABE SHUICHI OKADA NORIKO INOUE SHUHEI YAJIMA YUJI FUJII TAKEHIKO OHZEKI 《Pediatrics international》2003,45(1):60-64
BACKGROUND: In an effort to improve the quality of life of children with cancer, this study analyzes the signs and symptoms at the end of life in such children. It is hoped that these data will contribute to the development of appropriate programs to address the challenges faced by these children. PROCEDURE: Between 1994 and 2000, 28 children died after treatment for cancer at Hamamatsu University Hospital, Japan. The circumstances, signs and symptoms at the end of life of these children were analyzed through their medical records. RESULTS: Of the 28 children, the underlying diseases were leukemia/lymphoma (LL group; n=11), brain tumors (BT group; n=7), and other solid tumors (OST group; n=10). Records showed poor appetite (100%), dyspnea (82.1%), pain (75.0%), fatigue (71.4%), nausea/vomiting (57.1%), constipation (46.4%) and diarrhea (21.4%) among these children. Anxiety was reported in 53.6% of the entire group of 28 children; however, no child in the BT group manifested anxiety. However, disturbance of consciousness was reported in all children in the BT group, which was significantly greater than in the other groups. Awareness, fear or acceptance of the imminence of his/her own death as indicated by verbal expression was reported in nine children (32.1%). CONCLUSIONS: Using the data obtained in the present study, we describe situations faced in the terminal care of children. It is important to address the problems revealed by this analysis in order to achieve improvements in both the physical and psychological care of children with terminal cancer. 相似文献
4.
Beginning in the late 1980s, after a long period of declining interest in home care for the terminally ill, several projects and experiments were initiated in the Netherlands. This article describes this trend and provides background information on the Dutch health services, a definition of terminal home care, and statistical information about the different types of home care in the Netherlands. Findings from 3 recent studies of these projects and experiments are presented along with the guidelines for providing good terminal home care formulated by the Dutch Health Council in 1991. 相似文献
5.
应用原位杂交技术,观察了二乙基亚硝胺(DEN)诱发大鼠肝癌前病变组织中胎盘型谷胱甘肽S转移酶(GST-P)mRNA的表达。结果显示,GST-PmRNA主要在癌前病变肝组织中的变异灶及灶外卵圆形细胞内表达,且在变异灶间或和同一灶内阳性细胞间表达程度不尽一致,而正常肝、再生肝组织中未见其表达。提示在分子水平上变异灶细胞及卵圆型细胞可能成为实验性肝癌的癌前期细胞 相似文献
6.
重组O-GLcNAc糖基转移酶在昆虫细胞中的表达和纯化 总被引:1,自引:1,他引:0
蛋白质的 O- Glc NAc糖基化修饰是一种细胞核蛋白与细胞浆蛋白的蛋白质翻译后修饰。不同于膜蛋白和分泌蛋白的糖基化修饰 ,与蛋白质磷酸化修饰相似。催化蛋白质 O- Glc NAc糖基转移酶 ( OGT)已被克隆。用Hi5昆虫细胞系统表达并纯化了具有活性的重组 OGT。在 Hi5昆虫细胞中表达的鼠肝 OGT带有一 His 6标记片段。经镍离子螯合柱纯化后 ,其比活性达到 0 .88nmol· min- 1·m g- 1 OGT。因此本研究为进一步研究蛋白 O- Glc NAc糖基化修饰提供重要资源 相似文献
7.
George Wolf DPhil 《Nutrition reviews》2007,65(8):385-388
Retinol-binding protein (RBP) is the transport protein that carries retinol in the circulation from the liver to its target tissues. The existence of a cell-surface receptor on the target cells, which mediates the uptake of retinol from RBP, has been known since 1975. Recently, it was identified as an integral transmem-brane protein named STRA6 that is inducible by retinoic acid in certain cancer cells. The receptor was found to be highly specific for RBP, with high affinity, and to be localized in all tissues known to require retinol for their function, particularly the pigment epithelium of the eye. 相似文献
8.
9.
Yasuhiko Tamada Hiromichi Takama Toshihiko Ikeya Takashi Yokochi Hijiri Mori Yoshinari Matsumoto 《The Journal of dermatology》1995,22(12):913-916
Lewis Y (Ley) antigen, a difucosylated tetrasaccharide found on type 2 blood group oligosaccharides of glycolipids and glycoproteins, is thought to be a phenotypic marker predictive of cell differentiation. The distribution of this antigen in human anagen hair follicles was examined by immunohistochemical staining using a monoclonal antibody (AH-6) to Ley. In the bulbar and suprabulbar portion of anagen hair follicles, Ley antigen was detected in the three layers of the inner root sheath. Subsequently, the positive staining became translocated to the innermost layer of the outer root sheath in the middle part of the hair follicles. In the upper portion of the hair follicles, Ley antigen was found in the outer cells of the outer root sheath. These findings suggested that the expression of Ley antigen in the anagen hair follicles was correlated with the processes of keratinization or terminal differentiation. 相似文献
10.
异烟肼、利福平治疗肺结核致肝毒性易感基因的研究 总被引:2,自引:0,他引:2
目的:探讨N-乙酰基转移酶(NAT2)基因型与异烟肼、利福平治疗肺结核致肝毒性的相关性。方法:通过聚合酶链反应-限制性片段长度多态性(PCR—RFLP)技术分析67例经利福平、异烟肼治疗后发生或未发生肝功能异常的肺结核患者NAT2基因多态性的部位、性质及发生率。结果:病例组和对照组857位密码子多态性分别是20.3%和7.1%,两组差异显著。结论:NAT2基因型与异烟肼和利福平所致肝毒性关系密切,其中857位密码子点突变可能是结核患者发生肝毒性的易感基因型之一。 相似文献