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101.
目的 探讨血浆内皮素 (ET)及降钙素基因相关肽 (CGRP)在腰椎间盘突出症(PLID)患者手术前后的变化及其意义。方法 采用放射免疫法检测 40例正常人及 40例患者手术前后的血浆CGRP及ET值。结果  40例PLID患者术前血浆ET值明显高于正常对照组 ,术后ET值明显低于术前 (P <0 .0 1) ,但患者术后血浆ET值与正常对照组差异无显著性 (P >0 .0 5 )。40例PLID患者术前血浆CGRP值与正常对照组比较差异无显著性 (P >0 .0 5 ) ,40例PLID患者术后疼痛明显改善 ,且其血浆CGRP值明显高于术前及正常对照组 (P <0 .0 1)。正常对照组ET与CGRP无明显相关 ,病组术前ET与CGRP呈正相关 ,而术后两者无明显相关。结论 ET与CGRP共同参与了PLID的发病过程 ,为探讨PLID保守治疗方法提供了依据。  相似文献   
102.
S-4-methoxytrityl cysteine was synthesized and converted into the corresponding Fmoc-Cys(Mmt)-OH by its reaction with Fmoc-OSu. As compared to the corresponding Fmoc-Cys(Trt)-OH, the S-Mmt-function was found to be considerably more acid labile. Quantitative S-Mmt-removal occurs selectively in the presence of groups of the tert butyl type and S-Trt by treatment with 0.5–1.0% TFA. The new derivative was successfully utilized in the SPPS of Tyr1-somatostatin on 2-chlorotrityl resin. In this synthesis groups of the Trt-type were exclusively used for amino acid side-chain protection. Quantitative cleavage from the resin and complete deprotection was performed by treatment with 3% TFA in DCM–TES (95:5) for 30 min at RT. We observed no reduction of tryptophan under these conditions. © Munksgaard 1996.  相似文献   
103.
测定7例心力衰竭患儿及44例健康儿童血浆心钠素浓度,发现心力衰竭患儿血浆心钠素浓度较健康儿童增加,且与病情轻重有关,心力衰竭程度越重,心钠素浓度越高,此系心脏通过降低心脏前、后负荷以改善心功能的代偿机制。2个月至12岁健康儿童血浆心钠素水平不受性别及年龄的影响。  相似文献   
104.
All eukaryotic cells contain enzymes that are able to catalyze the transfer of Arg from tRNA to the N-terminus of naturally short lived or damaged cytosolic proteins. For certain test proteins, it has been shown that the addition of Arg to the N-terminus leads to their degradation via the ubiquitin proteolytic pathway. The mechanisms used by cells for identifying proteins for arginylation and regulating arginylation are not known. The present study reports the isolation of a peptide from rat brain that is able to inhibit the arginylation of proteins in brain extracts. We suggest that this peptide is the physiological regulator of arginylation in rat brain.  相似文献   
105.
A strategy for directing and enhancing B cell immune responses against synthetic peptide determinants has been developed in order to produce antibodies specifically against protein epitopes of clinical relevance. A peptide sequence based upon the MUC-1 mucin protein core was selected for this purpose since anti-MUC-1 antibodies have proven diagnostic application and therapeutic potential in human breast and ovarian cancer. Peptide constructs were synthesised co-linearly linking the immunodominant B cell determinant region, PDTRPAP, in the protein core of the MUC-1 mucin, to sequence 111 – 120 of influenza haemagglutinin A/X-31, a determinant recognised by T helper cells through association with MHC class II molecules. Induction of anti-MUC-1 antibodies to the B cell determinant region by immunisation with peptide was shown to be dependent upon both the presence and the position of the T cell determinant. In addition, haplotype mismatching with respect to the T cell determinant resulted in a significant lowering of the anti-MUC-1 antibody response in peptide construct immunised mice. These findings are relevant to the design of immunogens to produce antibodies against peptide epitopes of tumour associated proteins and glycoproteins.  相似文献   
106.
目的 为观察利多卡因对重型颅脑损伤患血浆降钙素基因相关肽、钙调素水平及其预后的影响。方法 将64例重型颅脑损伤患按随机原则分成利多卡因治疗组和常规治疗组,分别测定治疗前及治疗开始后第2、4、7天血浆CGRP、CaM含量,伤后6个月进行预后判断并进行比较分析。结果 重型颅脑损伤后患血浆CGRP水平下降而CaM水平升高,利多卡因治疗后可使上述改变显减轻并显改善患预后(P<0.05)。结论 重型颅脑损伤后血浆CGRP水平下降而CaM水平升高,参与了继发性脑损伤的病理生理过程,早期应用利多可因治疗可通过对CGRP和CaM水平的影响,减轻继发性脑损伤,发挥脑保护作用。  相似文献   
107.
目的 探讨降钙素基因相关肽对髂股静脉血栓形成的影响。方法 回顾性分析 5 0例髂股静脉血栓形成患者降钙素基因相关肽 (CGRP)的水平 ,以及对比研究联合应用尿激酶和复方丹参注射液治疗前后CGRP的变化。结果 急性髂股静脉血栓形成患者均存在高水平的CGRP ,与对照组比较具有显著性差异 (P <0 0 1) ;治疗后 6h血浆CGRP水平明显升高 ,3d达到最高峰 ,15d接近正常水平。结论 CGRP可以作为髂股静脉血栓形成的诊断指标之一 ,联合应用尿激酶和复方丹参注射液对髂股静脉血栓形成有较好的疗效。  相似文献   
108.
The use of in vitro immunization technology for the generation of human antigen-specific antibodies has essentially resulted in low affinity IgM antibodies, resembling an in vivo primary immune response. We now describe a detailed reproducible protocol for a two-step in vitro immunization, which yields isotype switched, antigen-specific human antibodies. The immunizing antigen was a 30aa synthetic peptide, containing both a B (15aa V3 peptide of the HIV-1) and a T helper cell epitope (15aa peptide from tetanus toxin). The immunization protocol includes: (i) a selection procedure of donors with a memory T cell response against tetatus toxoid; (ii) immunization of mature naive peripheral B lymphocytes in two distinct phases, involving a primary and a secondary step. None of the donors which were examined after primary 7immunization showed at any time an IgG anti-V3 specific antibody response, while all the donors showed an IgM response. After the secondary immunization step, anti-V3 antibodies of both IgM and IgG isotypes were detected. The switch frequency event was high among the tested donors (5/8).  相似文献   
109.
The synthesis is of Tyr(P)-containing peptides by the use of Fmoc-Tyr(PO3Me2)-OH in Fmoc/solid phase synthesis is complicated since, firstly, piperidine causes cleavage of the methyl group from the -Tyr(PO3 Me2)-residue during peptide synthesis and, secondly, harsh conditions are needed for its final cleavage. A very simple method for the synthesis of Tyr(P)-containing peptides using t-butyl phosphate protection is described. The protected phosphotyrosine derivative, Fmoc-Tyr(PO3tBu2)-OH was prepared in high yield from Fmoc-Tyr-OH by a one-step procedure which employed di-t-butyl N,N-diethyl-phosphoramidite as the phosphorylation reagent. The use of this derivative in Fmoc/solid phase peptide synthesis is demonstrated by the preparation of the Tyr(P)-containing peptides, Ala-Glu-Tyr(P)-Ser-Ala and Ser-Ser-Ser-Tyr(P)-Tyr(P).  相似文献   
110.
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