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11.
PUVA治疗诱导皮肤线粒体DNA 4977 bp缺失突变累积的研究   总被引:1,自引:0,他引:1  
为探讨线粒体DNA(mitochondrialDNA,mtDNA)4977bp缺失突变与皮肤光老化之间的关系,采用三条引物PCR的方法检测长波紫外线光化学疗法(PUVA)治疗的银屑病患者背部非皮损区皮肤mtDNA4977bp缺失突变的累积。结果发现,在PUVA治疗期间3~21天、治疗后1~6个月和治疗后6个月以上的各组活检标本中,发生4977bp缺失突变的mtDNA占总mtDNA比例分别为0.06,0.12和0.19,和未经PUVA治疗的对照组比较均有显著性差异(P<0.01)。表明线粒体DNA4977bp缺失突变累积与皮肤光老化密切相关,可能作为衡量皮肤紫外线损伤程度的分子生物学标志。  相似文献   
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13.
目的:探讨子宫内膜增生性病变与子宫内膜癌的超声鉴别诊断及内膜癌肌浸程度的估价.方法:采用术前B超、术后大体标本观察测量,对123例子宫内膜病变患者的声像图资料进行分析并与手术后病理结果对照.结果:①子宫内膜病变者子宫三径之和平均值均大于正常值;②58.6%的子宫内膜增生过长病变患者内膜形态以条形、梭形和正常形态回声;35%的Ⅱ期以上子宫内膜癌患者内膜回声以积液为主兼有其它图像类型;③大于50岁患者不同病理类型病变的子宫内膜平均厚度均超过其正常内膜厚度值,但无明显的规律性.小于50岁的患者内膜增厚主要以子宫内膜增生过长病变为主占48%;④通过超声测量子宫内膜厚度判断子宫内膜癌浅肌层和深肌层浸润符合率均为71.4%.结论:超声检查对判断子宫内膜病变病理类型有一定帮助,内膜厚度、内膜形态、回声特点、及内膜与肌层间的关系等,仅提示病变存在的可能性,要鉴别病变的良恶性、肌层浸润深度,须根据上述回声特点进行综合分析.  相似文献   
14.
原发性肝癌患者肝切除术前、后免疫细胞表型分析   总被引:1,自引:1,他引:0  
目的研究原发性肝癌(PrimaryLiverCarcinoma,PLC)患者肝切除术前、后免疫细胞表型的变化。方法采用直接免疫荧光标记,流量血细胞计数法(FlowCytometry,FCM)检测方法,动态观察120例PLC患者肝切除术前后外周血T淋巴细胞亚群、NK细胞和HLA鄄DR含量变化。结果肝切除术前肝功能Child鄄PughB级、OGTTL型和术前施行肝动脉栓塞化疗患者外周血CD8+T细胞含量明显低于正常人组,CD4+/CD8+比值则较高(P<0郾05)。全部肝癌患者肝切除术前、后CD3+CD4+T细胞和NK细胞(CD3-CD16+CD56+)含量无明显差异。术后第1天、第3天、第7天和第2周外周血淋巴细胞CD3+CD8+含量明显低于肝切除术前和术后第3周(P<0.01);而CD4+/CD8+比值则显著高于肝切除术前和术后第3周(P<0郾01)。结论PLC合并肝硬变肝储备功能不足、术前肝动脉栓塞化疗和肝切除术可导致机体细胞免疫功能低下,PLC患者肝切除术前行肝动脉栓塞化疗的价值有待深入研究。  相似文献   
15.
1 宋代社会经济、医事制度与历史地理 1.1 宋代的社会经济 宋朝是我国历史上继唐朝之后,社会经济发展、科技文化进步的一个历史时期,后世有"治隆唐宋"之说.公元960年陈桥兵变,赵匡胤(宋太祖)"黄袍加身"以后,遂代周而自立,是为宋朝,史称北宋.当时的社会在经历了五代十国的战乱之后而趋于安定,经济逐渐恢复,科学也日益发达.  相似文献   
16.
切开复位内固定治疗Gartland Ⅲ型肱骨髁上骨折   总被引:2,自引:0,他引:2  
目的探讨切开复位内固定治疗Gartland Ⅲ型肱骨髁上骨折的疗效。方法1999年10月-2005年4月,对62例平均年龄7.5岁的患儿,应用切开复位克氏针固定治疗Gartland Ⅲ型肱骨髁上骨折。其中伸直尺偏型41例,伸直桡偏型18例,伸直中间型3例;无伴发血管、神经损伤和筋膜室间隔综合征。闭合性骨折47例,开放性骨折15例。结果术后56例获得随访,随访时间为6~15个月,平均11.5个月。所有骨折均获得愈合。根据Flynn标准进行疗效评价,其中优22例(占39.3%),良21例(37.5%),可9例(16.1%),差4例(7.1%)。伤后8h内手术的优良率为89.7%,伤后8h后手术的优良率为63.0%。直接手术治疗的优良率为90.1%,曾接受手法复位的优良率为67.7%。结论切开复位内固定治疗Gartland Ⅲ型肱骨髁上骨折可取得满意的疗效,是安全、有效的治疗方法。  相似文献   
17.
Chymase is known to generate angiotensin II in the vascular wall. In this study we investigated a novel role for chymase other than angiotensin II production in vascular proliferation after balloon injury. Chymase promoted the migration of vascular smooth muscle cells in the matrix-coated invasion chambers and activated promatrix metalloproteinase-2 obtained from the culture medium of vascular smooth muscle cells. Two weeks after balloon injury, significant neointimal formation was found in dog carotid arteries. After injury, active matrix metalloproteinase-2 was increased in parallel with the augmentation of chymase activity that was seen in the proliferating region of the vascular wall. The oral administration of NK3201 (1 mg/kg per day), a chymase inhibitor, prevented neointimal formation and significantly suppressed both active matrix metalloproteinase-2 and chymase activities 2 weeks after injury. These results suggest that chymase inhibitors can prevent the development of intimal hyperplasia via the inhibition of matrix metalloproteinase-2 activation in balloon-injured arteries.  相似文献   
18.
The FIGNL1 gene was proven to be a new subfamily member of ATPases associated with diverse cellular activities (AAA proteins). In this in vitro study, the AAA proteins inhibited osteoblast proliferation and stimulated osteoblast differentiation. We showed that FIGNL1 may play some regulatory role in osteoblastogenesis. INTRODUCTION: The fidgetin-like 1 (FIGNL1) gene encodes a new subfamily member of ATPases associated with diverse cellular activities (AAA proteins). Although the FIGNL1 protein localizes to both the nucleus and cytoplasm, the function of FIGNL1 remains unknown. In a previous study, we identified several genes that mediate the anabolic effects of basic fibroblast growth factor (bFGF) on bone by using microarray data. FIGNL1 was one of the genes that downregulated >2-fold in MC3T3-E1 cells after treatment with bFGF. Therefore, this study was aimed to identify and confirm the function of FIGNL1 on osteoblastogenesis. MATERIALS AND METHODS: We examined the effect of the FIGNL1 gene on proliferation, differentiation, and apoptosis in mouse osteoblast cells (MC3T3-E1 and mouse primary calvarial cells) using flow cytometry, RT-PCR, cell proliferation assay, and cell death assay. MC3T3-E1 cells and mouse calvarial cells were transfected with small interfering RNA (siRNA) directed against the FIGNL1 or nontargeting control siRNA and examined by cell proliferation and cell death assays. Also, FIGNL1 was fused to enhance green fluorescent protein (EGFP), and the EGFP-fused protein was transiently expressed in MC3T3-E1 cells. RESULTS: Reduced expression of FIGNL1 by bFGF and TGF-beta1 treatment was verified by RT-PCR analysis. Overexpression of FIGNL1 reduced the proliferation of MC3T3-E1 and calvarial cells, more than the mock transfected control cells did. In contrast, siFIGNL1 transfection significantly increased the proliferation of osteoblasts, whereas overexpression of FIGNL1 did not seem to alter apoptosis in osteoblasts. Meanwhile, overexpression of FIGNL1 enhanced the mRNA expression of alkaline phosphatase (ALP) and osteocalcin (OCN) in osteoblasts. In contrast, siFIGNL1 decreased the expression of ALP and OCN. A pEGFP-FIGNL1 transfected into MCT3-E1 cells had an initially ubiquitous distribution and rapidly translocated to the nucleus 1 h after bFGF treatment. CONCLUSIONS: From these results, we proposed that FIGNL1, a subfamily member of the AAA family of proteins, might play some regulatory role in osteoblast proliferation and differentiation. Further analyses of FIGNL1 will be needed to better delineate the mechanisms contributing to the inhibition of proliferation and stimulation of osteoblast differentiation.  相似文献   
19.
The beta-adrenoceptor (beta-AR)-stimulatory guanine nucleotide-binding (Gs) protein system has been shown to play important roles in the cardiovascular system. The gene encoding the alpha-subunit of Gs proteins (GNAS1) is a candidate genetic determinant for hypertension. Because alcohol consumption is known to affect blood pressure partly through the beta-AR-Gs protein system, we examined the possible interaction between GNAS1 T393C polymorphism and drinking status in the association with hypertension in the present study. As a result, a non-significant but reasonable trend supporting the presence of an interaction was shown (p = 0.076). In line with this trend, the T393C polymorphism significantly interacted with drinking status in the association with systolic blood pressure (p = 0.028). Moreover, supporting the presence of an interaction, T allele carriers consistently had a higher probability of hypertension, higher systolic blood pressure, and higher diastolic blood pressure than CC homozygotes in non-drinkers and light drinkers. In contrast, CC homozygotes consistently had a higher probability of hypertension, higher systolic blood pressure, and higher diastolic blood pressure than T allele carriers in moderate to heavy drinkers. The present study also showed a significant interaction between the T393C polymorphism and drinking status in the association with pulse pressure (p = 0.026), reflected by a significant association between the T393C polymorphism and pulse pressure in moderate to heavy drinkers (p = 0.026). These findings may be helpful in conducting further molecular and biological studies on the relationship among the effects of alcohol, the beta-AR-Gs protein system, and hypertension.  相似文献   
20.
OBJECTIVE: To investigate the serial CT findings of Paragonimus westermani infected dogs and the microscopic structures of the worm cysts using Micro-CT. MATERIALS AND METHODS: This study was approved by the committee on animal research at our institution. Fifteen dogs infected with P. westermani underwent serial contrast-enhanced CT scans at pre-infection, after 10 days of infection, and monthly thereafter until six months for determining the radiologic-pathologic correlation. Three dogs (one dog each time) were sacrificed at 1, 3 and 6 months, respectively. After fixation of the lungs, both multi-detector CT and Micro-CT were performed for examining the worm cysts. RESULTS: The initial findings were pleural effusion and/or subpleural ground-glass opacities or linear opacities at day 10. At day 30, subpleural and peribronchial nodules appeared with hydropneumothorax and abdominal or chest wall air bubbles. Cavitary change and bronchial dilatation began to be seen on CT scan at day 30 and this was mostly seen together with mediastinal lymphadenopathy at day 60. Thereafter, subpleural ground-glass opacities and nodules with or without cavitary changes were persistently observed until day 180. After cavitary change of the nodules, the migratory features of the subpleural or peribronchial nodules were seen on all the serial CT scans. Micro-CT showed that the cyst wall contained dilated interconnected tubular structures, which had communications with the cavity and the adjacent distal bronchus. CONCLUSION: The CT findings of paragonimiasis depend on the migratory stage of the worms. The worm cyst can have numerous interconnected tubular channels within its own wall and these channels have connections with the cavity and the adjacent distal bronchus.  相似文献   
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