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61.
The aim of this study was to clarify and compare the temporal course of bone mineral density (BMD) between fast bone losers and normal residents in Miyama Village, a rural Japanese community. BMD was measured over a 10-year period in a cohort study in Miyama Village, Wakayama Prefecture, Japan, to provide information on rate of bone loss in the mature and elderly population. Subjects (n=400) were selected by sex and age stratum from the full list of residents born in 1910–1949, with 50 men and 50 women in each age decade. Baseline BMD of the lumbar spine and proximal femur was measured using dual energy X-ray absorptiometry in 1990, 1993, 1997 and 2000. In the cohort, 171 men and 189 women completed the follow-up survey performed in 1993. After calculating the rate of bone loss between 1990 and 1993, the greatest tertile from the distribution of bone loss was categorized as fast bone losers, with the remainder considered as normal subjects. Changes in BMD were compared between normal subjects and fast bone losers over the 10-year period. Mean rate of change for BMD at both lumbar spine and femoral neck in fast bone losers recovered to levels similar to those in normal subjects over 7 years of observation. By contrast, BMD at the lumbar spine and femoral neck decreased steeply over the 10-year period in both groups, and mean BMD for fast bone losers was significantly lower than that of normal subjects (P<0.05). These differences were apparent only at the lumbar spine in both men and women, even after adjusting for age. These results indicate that fast bone loss is a transient phenomenon rather than a fixed status, although individuals who have been categorized as fast bone losers at some stage continue to display low BMD in the lumbar spine.  相似文献   
62.
BACKGROUND: Although it is clear that dissemination via the blood system involves angiogenesis, it is uncertain whether tumors also induce lymphangiogenesis or simply invade existing peritumoral vessels. The purpose of this study was to elucidate changes in tumor blood and lymph vessels in cases involving the invasion of squamous cell carcinoma in the oral cavity, and its significance. Blood and lymph vessels densities in tongue carcinomas induced in hamsters were investigated. METHODS: Tongue cancer was induced by abrading the right margin of the tongue of each hamster with an endodontic barbed broach and subsequently applying 1.0% 9,10-dimenthl-1,2-benzanthracene (DMBA) dissolved in acetone, three times a week, at the same site. Fresh frozen sections were prepared and blood vessels stained blue by perfusion with Coomassie Brilliant Blue and lymph vessels stained brown for 5'-nucleotidase. The effects on the blood vessels and lymph vessels were observed. RESULTS: The results showed that blood and lymph vessel densities were greater in the advanced carcinoma tissues than in normal tissue. These were compared in terms of the mode of cancer invasion. As tumor invasion progressed, the blood vessel density decreased but lymph vessel density tended to be higher in high-degree tumor invasion than in low-degree tumor invasion. The expression of vascular endothelial growth factor-C was seen more frequently as tumor invasion progressed. CONCLUSIONS: The present findings indicated that angiogenesis and lymphangiogenesis are affected by cancerous invasion.  相似文献   
63.
用超离心法制备人血清高密度脂蛋白(HDL);甲醇/氯仿脱脂;经Sephadex G-150层析及DEAE-纤维素(DE-52)离子交换得纯化载脂蛋白A-I(Apo A-I),免疫新西兰兔,获得效价为1:32的特异性抗人Apo A-I抗血清。用本室建立的单向火箭免疫电泳法测定了158名健康中年人与9名老人的血清Apo A—I含量,结果发现:β-脂蛋白<5g/L,总胆固醇<2mmol/L的人血清Apo A-I含量男女分别为2.06±0.16g/L和2.07±0.15g/L;而β脂蛋白≥5g/L,总胆固醇≥2mmol/L的人血清Apo A-I含量男女分别为1.75±0.15g/L和1.82±0.1g/L,由此可见,血脂正常的男性和女性的Apo A—I含量均显著高于血脂高的男性和女性。80岁以上老年人的血清Apo A-I含量为2.1±0.1g/L,也在正常范围。与文献报道比较,我国人的血清Apo A-I含量高于外国人,这与我国人HDL水平较外国人高一致。  相似文献   
64.
体重、体质指数、腰围和腰臀比对正常成人骨密度的影响   总被引:2,自引:1,他引:1  
目的探讨体重、体质指数(BMI)和腰围、腰臀比(WHR)对正常成人骨密度的影响。方法采用MarcomMx8000多层螺旋CT测定560例正常成人腰椎松质骨密度,将受试者按年龄不同分为青年组、中年组和老年组,然后在同年龄组根据BMI及腰围的不同将受试者分为肥胖组和正常体重组,分析骨密度与体重、BMI、腰围及WHR的关系。结果①以BMI分组,老年肥胖组BMD高于体重正常组(P<0.05);②以腰围分组,中年女性肥胖组BMD低于非肥胖组(P<0.05);③青年组和中年组BMD与腰围及WHR呈负相关,老年组BMD与体重和BMI呈正相关与腰围和WHR不相关。结论预防骨质疏松症在中青年应提倡运动锻炼,避免肥胖,在老年人不应该过分强调降低体重减少肥胖以避免骨量的丢失。  相似文献   
65.
Abstract Surgical treatment of proximal humeral fractures still remains a challenge. This is primarily due to the fact that sufficient implant fixation in humeral head fractures is often not achieved due to substantial bone tissue loss with increasing age. In the last few years the locking plates and locking nails have been introduced into clinical practice with varying results. The biomechanical studies have focused on locking plate osteosynthesis as well. The following paper focuses on bone quality, biomechanical studies and biology of proper osteosynthesis and reviews the most recent literature.  相似文献   
66.
奥曲肽对肝动脉栓塞治疗大鼠肝癌影响的实验研究   总被引:2,自引:1,他引:1  
目的 观察奥曲肽(octreotide)降低肝动脉栓塞(HAE)促进肿瘤新生血管生长的作用以及抑瘤作用。方法 采用大鼠肝内种植Walker 256瘤株制作肝癌模型,分为对照组、Octreotide组、HAE组和HAE+octreotide组共四组。定期切取肿瘤标本测量肿瘤体积,检测标本中的血管内皮生长因子(VEGF)的表达及微血管密度(MVD)。结果 各干预组肿瘤体积均小于对照组(P<0.01), HAE+octreotide组肿瘤体积也小于 HAE组(P<0.05); HAE+octrotide组 VEGF表达低于HAE组(P<0.05);Octreotide组、HAE+octreotide组 MVD表达低于对照组(P<0.05)。结论 在对大鼠肝癌的治疗中,行肝动脉栓塞时联用奥曲肽,可降低单纯肝动脉栓塞引起的癌组织 VEGF高表达,减少肿瘤新生血管形成,加强其抑瘤作用。  相似文献   
67.
目的探讨多层螺旋CT(MSCT)肺密度测定对结缔组织病(CTD)肺间质病变(ILL)早期诊断的临床意义。方法对222例CTD患者及50名正常对照者,应用MSCT附带的Pulmo自动评估软件进行上、中、下肺区的密度测定,并同时进行肺高分辨扫描(}-IR(_1、),分析二者的变化与CTD伴ILL的关系。结果222例cm患者中197例平均肺密度有不同程度的增高,25例平均肺密度正常。157例HRCT有不同程度的肺间质病变,65例HRCT正常。50名正常对照者HRCT均正常,8名平均肺密度有不同程度的增高,42名平均肺密度正常。结论采用MSCT与HRCT对CTD伴ILL的检测结果差异有统计学意义,P=0.000(双侧),因此MSCT平均肺密度测定对早期诊断CTD伴ILL比HRCT更敏感,更有临床意义。  相似文献   
68.
审慎诊治脉络膜恶性黑色素瘤   总被引:1,自引:0,他引:1  
目的 探讨脉络膜恶性黑色素瘤的传统治疗、影像学临床特点及确诊符合率,以指导临床。方法 经临床确诊为脉络膜恶性黑色素瘤患者26例26眼,年龄41~73岁。术前视力0.2至光感。局部及全身检查除外肿瘤原发病灶及转移病灶。结果 26例行眼球摘除术,病理检查结果符合率为88.46%(23/26)。3例3眼病理检查结果为脉络膜出血。结论 审慎诊治脉络膜恶性黑色素瘤,提高确诊率,现代的包括手术在内的治疗方法应加以考虑。  相似文献   
69.
The accuracy of 2D phase contrast (PC) magnetic resonance angiography (MRA) depends on the alignment between the vessels and the imaging plane. PC MRA imaging of blood flow is challenging when the flow in several vessels is to be evaluated with one acquisition. For this purpose, semi-automatic determination of the plane most perpendicular to several vessels is proposed based on centerlines extracted from 3D MRA. Arterial centerlines are extracted from 3D MRA based on iterative estimation-prediction, multi-scale analysis of image moments, and a second-order shape model. The optimal plane is determined by minimizing misalignment between its normal vector and the centerlines’ tangent vectors. The method was evaluated on a phantom and on 35 patients, by seeking the optimal plane for cerebral blood flow quantification simultaneously in internal carotids and vertebral arteries. In the phantom, difference of orientation and of height between known and calculated planes was 1.2° and 2.5 mm, respectively. In the patients, all but one centerline were correctly extracted and the misalignment of the plane was within 12° per artery. Semi-automatic centerline extraction simplifies and automates determination of the plane orthogonal to one vessel, thereby permitting automatic simultaneous minimization of the misalignment with several vessels in PC MRA.  相似文献   
70.
目的 探讨以聚羟基乙酸(PGA)包裹特定形态的医用假体材料--多孔高密度聚乙烯(HDPE,商品名为MEDPOR)为支架,应用软骨细胞诱导骨髓基质干细胞(BMSCs),共培养构建特定形态的带内支撑组织工程化软骨医用假体的可能性.方法 以直径3 mm、长5 mm的圆柱形HDPE,外裹 1 mm厚PGA为支架,将体外分别培养的新生猪BMSCs和耳郭软骨细胞按7∶3混合,以10×10 7/ml细胞浓度接种于支架上,同时以相同浓度的单纯软骨细胞和单纯BMSCs分别接种,作为阳性对照组(PC组)和阴性对照组(NC组).经体外培养2周及在裸鼠皮下移植4、8周后取材 ,行大体观察、组织学、组织化学及免疫组化检测.结果 各组细胞均与材料黏附良好.实验组和阳性对照组均形成了大体形态良好的HDPE-软骨复合体,内支撑的HDPE与外层软骨结合紧密.组织学可见成熟的软骨陷窝结构,软骨渗入HDPE孔隙内部、异染基质及Ⅱ型胶原呈强阳性表达.结论 以HDPE为内支撑,外裹PGA的支架,接种混合细胞,可于皮下构建特定形态、组织学良好的HDPE-软骨复合体.  相似文献   
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