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61.
内源性转化生长因子β1对膀胱癌细胞体外生长的影响   总被引:2,自引:0,他引:2  
目的:研究内源性转化生长因子β1(TGFβ1)对膀胱癌细胞增殖的影响及机制。方法:构建携TGFβ1反义RNA的复制缺陷型逆转录病毒载体pRevTβ-AS,转染膀胱癌EJ细胞株,观察抑制内源性TGFβ1表达对EJ细胞体外增殖的影响;流式细胞仪分析转染后细胞周期时相分布的改变。结果:将TGFβ1反义RNA导入EJ细胞并有效表达;抑制TGFβ1表达可以降低靶细胞的生长速度和克隆形成率,使细胞增殖指数下降12%;反义RNA转染的EJ细胞G0和G1期细胞占65.7%,高于对照组细胞,S期细胞占20.5%,低于对照组细胞。结论:内源性TGFβ1通过诱导膀胱癌细胞G1→S期转换,促进肿瘤细胞体外增殖。  相似文献   
62.
63.
创伤性休克后血浆黏附分子的变化及不同复苏液的影响   总被引:7,自引:0,他引:7  
目的 探讨创伤性休克兔中性粒细胞黏附分子CD11b、血清可溶性细胞间黏附分子(sICAM ) 1的动态变化及不同复苏液的影响。方法  72只创伤性休克模型兔分为 6组 ,林格氏液组按失血量 2倍输入乳酸林格氏液 ,其他各组按 6ml/kg分别输入右旋糖酐 40、70 6代血浆、7.5 %氯化钠和 2 0 %白蛋白。分别采用流式细胞仪、酶联免疫吸附法检测CD11b、sICAM 1表达值。结果 各实验组休克 1hCD11b及sICAM 1表达增高 ,与对照组比较差异有显著性 (P <0 .0 5 ) ,并于12h达最高值 (林格氏液组 85 .6± 12 .1,60 9.3± 10 1.3 ;高渗盐组 77.5± 10 .3 ,5 18.5± 87.2 ;白蛋白组 78.2± 10 .7,5 2 2 .4± 88.3 ;P <0 .0 1)。高渗盐和白蛋白组 2 4、48hCD11b和sICAM 1分别为5 9 .2± 6.9,5 4.6± 5 .9;3 60 .1± 68.4,2 74.4± 40 .1;5 8.9± 6.4,5 5 .0± 5 .8;3 5 2 .6± 65 .3 ,2 70 .2±3 8.2 ,较林格氏液组 (72 .3± 10 .1,65 .8± 8.3 ;5 0 2 .6± 84.5 ,3 42 .4± 63 .1)降低 (P <0 .0 5 ) ;高渗盐和白蛋白组 (8.3 % )复苏 48h动物死亡率较林格氏液组 (4 1.7% )低 (P <0 .0 5 )。结论 创伤性休克时PMNCD11b和sICAM 1表达增加 ;采用 7.5 %氯化钠或 2 0 %白蛋白复苏时表达值及死亡率较乳酸林格氏液低。  相似文献   
64.
Both morphine (M) and naloxone (NL) have been reported to have NMDA receptor blocking effects, regarded as the reason of opiate physical dependence development. On the other hand, glutamate (GLU) has been known to induce the contraction of isolated guinea pig ileum via acetylcholine release. Therefore, different concentrations of M or NL were investigated on the 1 mM GLU-induced contraction of isolated guinea pig ileum fixed at a resting tension of 1 g in isolated organ bath. The mean value (359.3 +/- 20 mg) of the GLU-elicited contraction force was significantly reduced (318.4 +/- 19.4) by 25 nM M concentration in the medium. Consequently, 500 and 750 nM M caused further decreases in a rather dose-dependent manner (270.8 +/- 17.4 and 167.8 +/- 16.5 mg, respectively). One micromolar M contraction nearly abolished (8.0 +/- 8.2 mg) the GLU-induced contraction. A similar effect was obtained with the naloxone concentrations of 10, 20, 40, and 50 microM. In addition, NL has been shown to elicit the contraction of the isolated M-dependent guinea pig ileum. In the present study, 20- and 30-microM NL concentrations in the bathing medium caused the contraction of the ileum made M-dependent by preincubation with M (333.0 +/- 32.4 and 309.5 +/- 17.7 mg, respectively). These contraction forces were significantly reduced when the NL concentration was increased to 40 microM. And, 50 microM NL concentration not only failed to induce contraction but caused a relaxation (-10.6 +/- 2.3) as well. The results were considered supporting evidence for the fact that both M and NL are NMDA receptor blockers.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
65.
We have performed this technique bilaterally on 39 patients with chronic subluxation and 13 patients with recurrent dislocation since 1985 and have had good results with patient satisfaction. These patients had significantly higher articular eminences than normal control individuals. Also, we have used echography as a new application of an old technique, to evaluate the patients objectively in the preoperative and postoperative periods.  相似文献   
66.
67.
Abstract Alzheimer's disease (AD) is defined pathologically by the presence of β-amyloid plaques, neurofibrillary tangles and extensive neuronal loss. Evidence indicates that increased DNA damage may contribute to neuronal loss in AD. Recently, it has been shown that in AD neurons have a reduced capacity for some types of DNA repair. Polymorphisms in DNA repair genes may be associated with differences in repair efficiency of DNA damage. Variants of several DNA repair genes, including the base excision repair gene XRCC1, have been described previously. We hypothesised that Arg194Trp polymorphism of XRCC1 gene may contribute to genetic susceptibility for AD. In order to test this hypothesis, we investigated Arg194Trp polymorphism at the XRCC1 gene in the DNA samples of 98 patients with AD and 95 healthy subjects. The frequency of the Trp allele was more pronounced among cases (11.2%) compared with controls (5.8%). On combining the homozygous and heterozygous variants of each codon, the variants seemed to be at twofold risk of AD, although the risk estimates were not statistically significant (OR=1.95, 95% CI 0.88–4.34, p=0.09). In addition, the 194Trp allele revealed a borderline significance (OR=2.05, 95% CI 0.96–4.37, p=0.056). According to our results, it may be speculated that the polymorphic variants of XRCC1 codon 194 have a role in the development of AD.  相似文献   
68.
p21对缺血-再灌注损伤后肾小管上皮细胞演变的影响   总被引:2,自引:0,他引:2  
目的 探讨p21对缺血-再灌注损伤(IRI)后肾小管上皮细胞演变的影响。方法 选择低龄(2个月龄)和高龄(12个月龄)p21(+/+)和p21(-/-)鼠,建立左肾IRI模型。于IRI后0、1、3、7d及1、3、6个月光镜下观察肾小管组织学变化,采用免疫组化法检测肾小管上皮细胞增殖细胞核抗原(PCNA)表达,组织化学染色观察肾小管上皮细胞衰老相关β-半乳糖苷酶(SA-β-gal)活力,末端脱氧核糖转移酶介导的生物素化脱氧尿嘧啶缺刻标记技术(TUNEL)检测肾小管上皮细胞凋亡。结果 IRI后0d,肾小管以坏死为主,高龄鼠比低龄鼠严重、p21(-/-)鼠比p21(+/+)鼠严重(P均〈0.05)。肾小管上皮细胞凋亡在IRI 1d后出现,7d达高峰,且高龄鼠比低龄鼠明显、p21(-/-)鼠比p21(+/+)鼠明显(P均d0.05)。低龄鼠IRI后1个月出现SA—β-gal染色阳性的肾小管上皮细胞,而对侧肾此时未见衰老细胞,3和6个月时衰老的肾小管上皮细胞显著增多,且p21(+/+)鼠比p21(-/-)鼠明显(P〈0.05);p21(+/+)高龄鼠IRI后0d双肾即可见大量的SA-β-gal染色阳性肾小管上皮细胞,且较p21(-/-)鼠显著增多(P〈O.05),但1d后,p21(+/+)和p21(-/-)鼠IRI肾衰老细胞均明显减少(P均〈0.05),1个月后又呈进行性增加,且p21(+/+)鼠始终比p21(-/-)鼠严重。高龄和低龄p21(+/+)鼠PCNA阳性染色细胞出现的几率差异无显著性(P〉0.05),但低龄鼠细胞增殖能力要强于高龄鼠;而p21(-/-)鼠的细胞增殖能力明显强于p21(+/+)鼠,低龄鼠更为显著(P均〈0.05)。对高龄鼠IRI后1d细胞衰老和凋亡进行相关分析显示,二者呈显著负相关Cp21(+/+)鼠:r=-0.82,P〈0.001,p21(-/-)鼠:r=-0.76,P〈0.0013。结论 ①IRI可促进正常肾小管上皮细胞衰老的进程;②已经进入衰老状态的肾小管上皮细胞在遭受IRI刺激后,更易走向死亡[坏死和(或)凋亡];③p21在IRI所致肾小管上皮细胞演变过程中发挥重要的调控作用。  相似文献   
69.
There are 2 main factors contributing to the strength of tendon repair: the tensile strength of the material used in repair and the tendon-holding capacity of the suture configuration. In the current study, we aimed to find a technique with high repair strength by increasing both the tensile strength of the material and the tendon-holding capacity of the configuration. We developed metal implants (models 1 and 2) made from stainless-steel wire with 2 different spiral-shaped configurations. We measured tendon-holding capacities of these alternative implants biomechanically and compared them with frequently used suture techniques, the Bunnell and locking loop, which were achieved with 5 Ticron sutures. Sixty-four sheep Achilles' tendons were used in the study as 16 tendons in each group. Model 2 was more resistant to deformation under loading when compared with model 1. The results demonstrated that model 2 was superior to model 1 and both suture techniques. This study could be accepted as a step for reaching a strong tendon repair technique. It should be emphasized that the technique needs to be improved technically to make it convenient for clinical use.  相似文献   
70.
Ischemic changes and acute or subacute cardiac failure after arterial switch operation generally results from imperfect transfer of coronary arteries to the neoaorta. Peroperative and early postoperative myocardial ischemia is the main cause of death in these patients. We present an unusual cause of myocardial ischemia and cardiac failure after arterial switch: a congenital coronary artery fistula between the circumflex artery and the right ventricle. The symptoms imitate coronary translocation failure. In differential diagnosis of the coronary perfusion problems encountered after the arterial switch operation, coronary artery fistula should not be forgotten, although it is rare.  相似文献   
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