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51.
目的研究CD44v9和基质金属蛋白酶-9(MMP-9)在结直肠癌和癌旁组织中表达的临床意义。方法采用RT-PCR方法分别检测46例结直肠癌及癌旁组织CD44v9及MMP-9的阳性表达情况。结果46例结直肠癌组织中CD44v9和MMP-9的阳性表达率分别是58.7%和82.6%,明显高于癌旁组织(58.7%和47.8%),两者比较差异均有统计学意义(P<0.001)。CD44v9和MMP-9在结直肠癌组织的阳性表达率与肿瘤的大小、分化高低、浸润深度、临床分期及淋巴结转移相关,而且两者在结直肠癌中的表达呈正相关。结论CD44v9和MMP-9与结直肠癌侵袭和转移性有关,可作为预测肿瘤转移潜能的指标。  相似文献   
52.
目的本文检测血管内皮生长因子(VEGF)和基质金属蛋白酶(MMP-9)在大肠癌患者血清中的水平,探讨其与大肠癌恶性程度、浸润、转移的关系。方法用ELISA法对48例大肠癌患者及40例正常对照者血清VEGF和MMP-9进行检测。结果大肠癌患者血清VEGF、MMP-9的水平分别为(665.8±232.8)ng/L;(532.7±208.9)ug/L。显著高于对照组(391.6±135.2)ng/L;(317.8±132.2)ug/L(P<0.01)。并与组织分化程度、Duke’s分期有关。低分化者及C、D期患者较中、高度分化及A、B期高(P<0.01)。结论大肠癌患者血清VEGF和MMP-9水平增高,与肿瘤的组织分化程度、转移、分期有关,提示VEGF、MMP-9对大肠癌恶性程度的判断有一定的价值。  相似文献   
53.
54.
Automatic analysis of electromyography (EMG) signals, first operated in 1950 with analogic machines, steeply expanded from 1980 when fast computers and worthwhile programs became available. On-line measurement of response area and latency, averaging of low amplitude waves, fast sorting of motor unit potential shape parameters, computation of the “jitter” between two muscle fibers, turns/amplitude and spectral analysis of interferential pattern records, are some examples of programs currently offered in modern EMG machines. Other techniques are still reserved for research purposes: scanning EMG, decomposition of nerve and muscle compound potentials, measurement of the threshold and firing rate of motor units, trace analysis using tracking models. Finally, the credit for artificial intelligence systems (knowledge based systems, fuzzy logic, neuronal networks) is still not clearly stated.  相似文献   
55.
Four of 82 patients with Guillain-Barré syndrome (GBS) and 1 of 12 with multifocal motor neuropathy (MMN), who previously had had Mycoplasma pneumoniae infections, had serum antibody to galactocerebroside (Gal-C). Two patients with GBS without mycoplasma infection also had anti-Gal-C antibody, whereas none of the normal or the disease controls had it. As Gal-C is a major glycolipid antigen in myelin, anti-Gal-C antibody may function in the pathogenesis of autoimmune demyelinative neuropathies. Mycoplasma pneumoniae appears to be an important preceding infectious agent in autoimmune neuropathies with anti-Gal-C antibody. © 1995 John Wiley & Sons, Inc.  相似文献   
56.
Abstract: We analyzed the expression of CEA, CA19-9, CA125, CA15-3 (DF3), PCNA and p53 immunohistochemically in 14 tissue specimens of mucosal cancers in adenoma, seven tubulovillous adenoma specimens, and 16 tubular adenoma specimens. The rates of positive staining for mucosal cancer in adenoma, tubulovillous adenoma and tubular adenoma specimens, respectively, were: for CEA: 100%, 85.7% and 75%; for CA19-9: 71.4%, 71.4% and 56.2%; for CA125:0%, 0% and 0%;for CA15-3 (DF3): 64.3 %, 0% and 0 %; for PCNA: 100%, 88.9% and 56.2%; and for p53: 35.7%, 0% and 0% . The results suggest that the expressions of CEA, CA19-9, CA15-3 (DF3), PCNA and p53 are related to colorectal tumorigenesis. None of the specimens studied showed staining for CA125, suggesting that CA125 is not involved in the early stages of colorectal carcinogenesis. There was no significant difference in the rates of positive staining for CEA and CA19-9 among mucosal cancer in adenoma, tubular adenoma and tubulovillous adenoma specimens. However, the rates of positive staining for PCNA and p53 were significantly higher in mucosal cancer in adenoma specimens than for tubular adenoma specimens (p<0.05), and the rate of CA15-3 (DF3) positive staining was significantly higher for mucosal cancer in adenoma than for tubulovillous adenoma (p<0.01) and tubular adenoma (p< 0.001) specimens. Therefore, the CA15-3 (DF3) antigen is an immunohistochemical marker for colorectal carcinomas. The present results suggest that CA15-3 (DF3), PCNA and p53 play important roles in the genesis of colorectal adenomas.  相似文献   
57.
目的:观察地塞米松(DXM)对哮喘大鼠Th1/Th2失衡以及嗜酸细胞(EOS)fas、bcl-2 mRNA表达的影响,探讨糖皮质激素治疗哮喘气道炎症的作用机制.方法:清洁级雄性SD大鼠30只,随机分为3组:正常对照组(C),哮喘组(A),地塞米松治疗组(T),每组10只.采用卵清白蛋白制作大鼠哮喘模型.用夹心酶联免疫吸附试验(sandwich ELISA)法检测血浆及支气管肺泡灌洗液(BALF)中IL-4、IFN-γ的水平;用原位杂交法检测fas和bcl-2 mRNA在气道壁EOS上的表达.结果:A组大鼠IFN-γ表达水平较C组明显下调(P<0.01),同时IL-4表达水平则有明显上调(P<0.01),表现出明显的Th1/Th2失衡.fas mRNA的表达在A组明显下降(P<0.01),bcl-2 mRNA的表达则有明显上调(P<0.01).地塞米松治疗在纠正A组大鼠Th1/Th2失衡的同时可上调fas mRNA的表达,下调bcl-2 mRNA的表达.结论:纠正哮喘大鼠Th1/Th2失衡,调节EOS fas、bcl-2 mRNA的表达是地塞米松减轻哮喘气道炎症的可能机制之一.  相似文献   
58.
Introduction. – L'objectif de cette étude est d'observer l'influence des paramètres anthropométriques sur la performance en aviron, chez des rameurs de niveau national et international.Synthèse des faits. – Les mesures anthropométriques ont été réalisées sur 88 rameurs (dont 11 évoluant au niveau international) lors des championnats de France de 2002. Ces mesures ont été corrélées aux performances réalisées sur ergomètre et en bateau. Des différences significatives sont mises en évidence entre les caractéristiques anthropométriques des rameurs de niveau national et international. Ces caractéristiques semblent être reliées directement aux performances ergométriques et non à celles réalisées en bateau.Conclusion. – L'influence des caractéristiques anthropométriques sur la performance en aviron pourrait être modifiée en fonction des niveaux de compétition.Aim. – Observe the influence of anthropometrics characteristics on rowing performance, at national and international level.Results. – Anthropometrics measurements of 88 rowers (included 11 international rowers) were realized during the national championships, data were correlated to ergometer and boat performances. Significant differences appear between anthropometrics characteristics of national and international rowers. Anthropometrics parameters seem related to ergometer performance but not to boat performances.Conclusion. – The influence of anthropometrics characteristics on rowing performance could be modified by the competitive level.  相似文献   
59.
目的 :探讨超声引导下经皮穿刺活检与CA19 9联合检测对胰腺占位性病变的诊断价值。 方法 :对 30例超声检查怀疑胰腺占位性病变者行血清学CA19 9检测 ,并在体表B超引导下 ,用 18G或 19G切割活检针和 2 2G抽吸活检针行组织学和细胞学检查。 结果 :CA19 9诊断的敏感性为 92 % ,特异性 5 0 % ,准确性 92 %。超声引导经皮穿刺活检 30例患者总穿刺成功率为 93.3% (2 8/ 30 ) ,2 6例胰腺癌患者穿刺成功率为 92 .3% (2 4 / 2 6 ) ,活检阳性者 2 3例 ,其诊断敏感性为 88.4 % ,特异性 10 0 % ,准确性 88.4 %。CA19 9与超声引导经皮穿刺活检联合检测对胰腺占位性病变诊断的敏感性为 92 .3%、特异性 10 0 %、准确性 92 .3% ,与单行超声引导经皮穿刺活检比较有显著差异 (P <0 .0 5 ) ,而且对患者的治疗及预后有指导意义。穿刺结束后除个别患者有轻微腹痛外 ,无一例出现出血、胰瘘及胃穿孔等并发症。 结论 :体表B超引导下经皮穿刺与CA19 9联合检测对胰腺占位性病变诊断的敏感性、特异性、准确性较单一检测高 ,而且对患者的治疗及预后有一定价值 ,是一种安全、可靠的方法。  相似文献   
60.
It has been demonstrated in our previous studies that Calbindin-D9k (CaBP-9k) is a potent biomarker for screening estrogen-like chemicals in the rat model. Although treatments with 17beta-estradiol (E2) and endocrine disrupting compounds resulted in the up-regulation of uterine CaBP-9k, the mechanism of CaBP-9k induction by these compounds through two subtypes of estrogen receptors (ERalpha and ERbeta) is unclear. Thus, in the present study, immature rats were treated with propyl pyrazole triol (PPT, an ERalpha-selective ligand), diarylpropionitrile (DPN, an ERbeta-selective ligand), E2, or dimethyl sulfoxide (DMSO, a vehicle control) for three days in order to clarify which subtype of ER is involved in the uterine CaBP-9k induction. Following injection with these ER ligands, uterine CaBP-9k expression was analyzed by Northern blot and immunoblot assays. Uterine CaBP-9k expression is mainly mediated by PPT in a dose- and time-dependent manner in immature rats, whereas no significant alteration of the uterine CaBP-9k gene was observed after DPN treatment. In addition, an estrogenicity of PPT in inducing CaBP-9k expression was completely blocked by the anti-estrogen ICI 182,780, implying that uterine CaBP-9k is solely induced by ERalpha. A single treatment with PPT rapidly increased the protein levels of ERalpha and PR, an E2-mediated gene, in these tissues. Taken together, these results indicate that uterine CaBP-9k is induced by E2 and endocrine disrupting chemicals via the ERalpha pathway, but not ERbeta, in the uterus of immature rats.  相似文献   
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