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81.
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   
82.
目的探讨血液透滤清除IL-6在重症急性胰腺炎治疗中的作用及机理。方法根据诊断标准对2002年7月至2006年6月来我院就诊的178例重症急性胰腺炎患者随机分组:血滤组(HF组)85人,非血滤组(NHF组)93人。比较两组患者局部和全身表现,观察各时相点促炎细胞因子血清IL-6的测定值的差异。结果HF组与NHF组比较:腹痛腹胀持续时间为(18.8±4.2)hvs(89.7±28.1)h(P〈0.05);治疗后第10天APACHEⅡ积分为(5.5±3.6)分vs(13.8±3.8)分(P〈0.05);住院天数和医疗费为(28.2±12.4)天vs(42.4±11.2)天和(4.38±2.8)万元vs(7.46±2.2)万元,(P〈0.05)。治疗后各时相点血清IL-6检测结果:HF组较NHF组显著降低(P〈0.05);MODS发病率和病死率分别为12.47%vs.36.28%和4.28%vs.12.82%,两者差异有统计学显著意义(P〈0.05)。结论早期短时血滤有利于纠正重症急性胰腺炎患者血清促炎细胞因子过度释放,使病情减轻,降低MODS发病率和病死率,提高疗效。  相似文献   
83.
CD44v6、P27蛋白在乳腺癌组织中的表达及意义   总被引:3,自引:0,他引:3  
目的 探讨乳腺癌中CD44v6、p27蛋白表达的意义。方法 应用免疫组化S-P法检测65例乳腺癌中CD44v6、p27蛋白表达。结果 65例乳腺癌中CD44v6、p27蛋白表达总阳性率分别为58.4%、38.4%。CD44v6蛋白阳性表达率与乳腺癌组织学类型、腋淋巴结转移呈正相关(P<0.05,P<0.01),与预后呈负相关(P<0.01),与组织学分级无明显相关性(P>0.05);p27蛋白阳性表达与乳腺癌组织学类型、组织学分级及腋淋巴结转移呈负相关(P<0.05),与预后呈正相关(P<0.05)。结论 CD44v6、p27蛋白表达与乳腺癌浸润、转移及预后显著相关,检测乳腺癌中CD44v6、p27蛋白表达水平,对判断乳腺癌恶性程度、复发转移潜能,评估患者预后及术后选择合理治疗方案有一定参考价值。  相似文献   
84.
Early multiple organ dysfunction syndrome appears to be facilitated with bacterial translocation in severely burn injury, yet the mechanisms of bacterial translocation remains in dispute. The aim of this study was to investigate the potential role of intestinal bifidobacteria in the pathogenesis of gut-derived bacteria/endotoxin translocation following burns and the effects of bifidobacterial supplement on gut barrier. Methods: Wistar rats were randomly divided into burn group (Burn, n=60),sham burn group (SB, n=10) in experiment Ⅰ , and burn + saline group (BS, n=30), burn + bifidobacteria group (BB, n=30), and sham-burn + saline group (SS, n= 10) in experiment Ⅱ. Animals in BB group were fed bifidobacterial preparation (5 × 109 CFU/ml) after burns, 1.5ml,twice daily. Animals in BS and SS were fed saline. Samples were taken on days 1, 3, and 5 in burn groups, and on day 3 in sham-burn groups. The incidence of bacteria/endotoxin translocation and counts of Bifidobacterium, Fungi and Escherichia coli in gut mucosa were determined with standard methods. The levels of sIgA in mucus of small intestine were measured by RIA. The positive sIgA expression in lamina propria and ileum mucosal injury was evaluated light microscopically by blinded examiners. Results: Our results showed that the incidence of bacterial translocation was increased after burns, which was accompanied by significant decrease in number of bifidobacteria but significant increase in E. coli and fungi in gut mucosa, and elevation of levels of plasma endotoxin and IL-6 (P<0. 001).The incidence of bacterial translocation was markedly reduced after 3- and 5-day supplementation of bifidobacteria compared with control group (P<0.05). The counts of mucosal bifidobacteria were increased by 4- to 40-fold,while E. coli and fungi were decreased by 2- to 30-fold and 10- to 150-fold, respectively, after bifidobacterial supplementation in contrast to control group. The damage of mucosa tended to be less pronounced after 3-day bifidobacteria-supplemented formula compared with control group [grade 2(0-6) vs. grade 4(3-6), P<0.05]. Moreover, the expression and release of sIgA was markedly augmented after 3-day bifidobacteria-supplementation formula and it returned to normal range on day 5. Conclusion: The decrease in counts and proportion of bifidobacteria in mucous membrane flora may play an important role in the development of bacteria/endotoxin translocation following thermal injury. The supplement of exogenous bifidobacteria could per se improve gut barriers, and attenuate bacteria/endotoxin translocation secondary to major burns.  相似文献   
85.
C. Hawkes  S. Kar   《Brain Research Reviews》2004,44(2-3):117-140
The insulin-like growth factor-II/mannose-6-phosphate (IGF-II/M6P) receptor is a multifunctional single transmembrane glycoprotein which, along with the cation-dependent M6P (CD-M6P) receptor, mediates the trafficking of M6P-containing lysosomal enzymes from the trans-Golgi network (TGN) to lysosomes. Cell surface IGF-II/M6P receptors also function in the degradation of the non-glycosylated IGF-II polypeptide hormone, as well as in the capture and activation/degradation of extracellular M6P-bearing ligands. In recent years, the multifaceted role of the receptor has become apparent, as several lines of evidence have indicated that in addition to its role in lysosomal enzyme trafficking, clearance and/or activation of a variety of growth factors and endocytosis-mediated degradation of IGF-II, the IGF-II/M6P receptor may also mediate transmembrane signal transduction in response to IGF-II binding under certain conditions. However, very little is known about the physiological significance of the receptor in the function of the central nervous system (CNS). This review aims to delineate what is currently known about IGF-II/M6P receptor structure, its ligand binding properties and role in lysosomal enzyme transport. It also summarizes the recent data regarding the role of the receptor in the CNS, including its distribution, possible importance for normal and activity-dependent functioning as well as its implications in neurodegenerative disorders such as Alzheimer's disease (AD).  相似文献   
86.
The medial globus pallidus plays a crucial role in generation of L‐DOPA‐induced dyskinesia in patients with Parkinson's disease. The 6‐hydroxydopamine‐lesioned rat exhibiting behavioral sensitization to L‐DOPA is one useful animal model for examining L‐DOPA‐induced dyskinesia. To determine neuropathological abnormality responsible for behavioral sensitization, the medial globus pallidus and the substantia nigra reticulata in 6‐hydroxydopamine‐lesioned rats treated with L‐DOPA were examined. Intermittent L‐DOPA treatment induced hypertrophy of the lesioned‐side of medial globus pallidus and substantia nigra reticulata of 6‐hydroxydopamine‐lesioned rats with behavioral sensitization to L‐DOPA. Additionally, coadministration of a 5‐HT1A receptor agonist, 8‐hydroxy‐2(di‐n‐propylamino)tetralin with L‐DOPA, alleviated the hypertrophy with improvement of the behavioral sensitization. These results suggest that hypertrophy of the medial globus pallidus and substantia nigra reticulata is associated with induction of behavioral sensitization to L‐DOPA in 6‐hydroxydopamine‐lesioned rats. Therefore, neuropathological changes corresponding to hypertrophy might underlie L‐DOPA‐induced dyskinesia in patients with Parkinson's disease.  相似文献   
87.
胃癌是最常见的癌肿之一,应用原位杂交技术检测胃癌组织中IL—6及其受体mRNA的表达情况,具有灵敏度高、特异性强的特点,而且较直观地在组织原位和转录水平对标本中IL—6及其受体进行研究,这使得形态学观察与功能学检测相结合,更能反映胃粘膜不同病变细胞分泌IL—6及其受体的情况。  相似文献   
88.
目的:在基因表达水平上研究黏附分子(E-cadherin,CD44v6)与卵巢癌转移的关系。方法:用免疫组化S-P法,选取1997~2002年间石蜡包埋的卵巢上皮性肿瘤组织块107块,其中良性上皮性肿瘤30例,交界瘤13例,恶性34例(Ⅰ、Ⅱ期4例,Ⅲ、Ⅳ期30例),对30例恶性晚期(Ⅲ、Ⅳ期)病例选取对应的大网膜转移组织。结果:30例良性上皮性肿瘤组织中,E-钙黏附蛋白100%强阳性表达,CD44v6100%阴性。13例交界瘤中,E-钙黏附蛋白有11例(84.6%)强阳性,CD44v6有1例弱阳性表达。34例恶性上皮性肿瘤中,E-钙黏附素有24例(70.6%)阳性表达,CD44v6有11例(32.4%)阳性表达。二指标在良性上皮性肿瘤与卵巢癌之间的阳性表达有显著性差异(P=0.001,P=0.000)。二指标在原发灶和大网膜转移灶之间表达无显著差别(P=1.000,P=1.000)。结论:E-cadherin及CD44v6在上皮性卵巢肿瘤中的表达呈相反趋势,E-cadherin及CD44v6与卵巢癌组织学分级及预后无明显相关性。  相似文献   
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