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61.
Determination of bone mineral density by dual x-ray absorptiometry in patients with uncemented total hip arthroplasty. 总被引:9,自引:0,他引:9
Bone remodeling is an expected sequela with total hip arthroplasty (THA). Although there are several methods of estimating bone response in THA patients from radiographs, there are no accurate and generally accepted methods for quantitative determinations in vivo. In this study, we describe an application of dual x-ray absorptiometry (DXA) for measuring bone mineral content and bone mineral density in the proximal femur following THA. DXA is a noninvasive technique with minimal radiation exposure (< 5 mrem). Various aspects of measurement error (accuracy and reliability) of this application of DXA were determined in a series of studies reported here. Accuracy error (how similar are the measured and actual values) was < 1% determined in bone phantoms of four densities. Precision error (how reproducible are the measurements) was also < 1% at all four densities in the phantoms and was only slightly elevated (0.9-1.5%) in repeated measurements of implanted cadaver femora. Precision error in vivo, determined both from multiple replicates on five patients and from duplicate scans on 30 patients, was further elevated but remained < 5%. Contributions to precision error, rotation of the leg, and interoperator variability were assessed; none was found to elevate precision error appreciably. We suggest that DXA is a feasible method for quantifying bone response following THA, and will allow discrimination of small changes (> 5%) not previously measurable. 相似文献
62.
Contact finite element stress analysis of porous ingrowth acetabular cup implantation, ingrowth, and loosening 总被引:2,自引:0,他引:2
Two-dimensional linear and contact finite element analyses were conducted of total hip arthroplasty using metal-backed, porous ingrowth acetabular components. The stress transmission characteristics from the component to the surrounding bone were given special attention. Resultant loads of 20 and 40 degrees medial of vertical were studied, and the influence of adding a metal flange to the rim of the cup was evaluated. The results indicated that when a conventional metal-backed component (without a flange) is initially implanted and subjected to normal loading, these components may experience distraction between the component and the surrounding bone at inferior sites. Compressive stresses in the superior dome cancellous bone, however, will be substantial. If complete porous ingrowth is achieved, the superior dome compressive stresses will be reduced and substantial shear stresses created. In addition, high local bone stresses were found at the component rim. If bone ingrowth is achieved only in specific locations, stress transmission will be dictated by those locations and may differ markedly from the case of complete bone ingrowth. In the event that no porous ingrowth is achieved and a fibrous layer forms around the component, the interface stresses will be similar to those calculated for the natural hip. The addition of a flange to the rim of the cup will reduce the magnitude of the radial stresses transmitted to the cancellous bone superiorly and medially by directly transferring some of the load to the lateral wall of the pelvis. The flange will also help to relieve the high local stresses that are found at the component rim. 相似文献
63.
目的 探讨全胃切除术后保留幽门间置空肠代胃术的临床应用。方法 1987年至今,对60例胃癌患者临床应用保留幽门的间置空肠代胃术式,评估其疗效。结果 60例患者无手术死亡,术后幽门舒缩功能及代胃的食糜搅拌、贮存功能良好,无返流性食管炎、倾倒综合症、营养不良等并发症。结论 保留幽门的间置空肠双腔代胃术能明显地改善全胃切除术后患者的生活质量。 相似文献
64.
65.
目的 研究影响或导致儿童甲状腺肿大率(甲肿率)、尿碘、盐碘三项指标变异程度的因素。方法 用设计效率(DEFF)作为评价变异程度的指标。结果 在西部12省中,儿童甲肿率的DEFF在3.0左右的有9个省,占75.0%;尿碘水平的DEFF在1.0~3.5之间的有6个省,占50.0%;合格碘盐食用率的DEFF有11省在3.0以上。有4个省加碘盐覆盖率的DEFF在3.0左右。结论 除了充分考虑非抽样因素对甲肿率、尿碘、盐碘三项指标变异程度的影响外,还应对西部监测中样本的数量作进一步的推算,使样本量这一影响指标变异程度的主要因素更加科学、合理,从而为全国的碘缺乏病监测工作提供科学依据。 相似文献
66.
Optimal surgery remains the mainstay of best outcome for rectal cancer. The demonstration, during the 3rd Annual Pelican Surgical Workshop Symposium, of an abdomino‐perineal excision (APE) performed in the ‘Berlin position’, further added to the debate on optimal surgical technique. Much interest was created at the 1st Pelican symposium with the demonstration, by the Swedish surgeon Dr Torbjorn Holm, of a prone APE and the delivery of a ‘cylindrical’ specimen and the potential to reduce local recurrence using this approach. The high rates of local recurrence following APE and the discussions as to optimal technique have led to the development of a proposed MERCURY Study Group study to assess the benefit of a radical APE, with careful assessment of the impact that this operation may have on morbidity. A German study has also been proposed adopting the UK's multidisciplinary team approach. It aims at targeting preoperative chemoradiotherapy at those patients in whom a radical APE or total mesorectal excision is likely to result in an involved surgical resection margin. In this article we review the evidence for improving the surgical technique for low rectal cancer. We believe improvements may be best achieved through continued European prospective, multi‐centre, multidisciplinary studies. 相似文献
67.
A M Abdel Gader A A Al-Mishari S A Awadalla N M Buyuomi T Khashoggi M Al-Hakeem 《International journal of gynaecology and obstetrics》2006,95(3):248-253
OBJECTIVE: To clarify the role played by tissue factor pathway inhibitor (TFPI) in pregnancy hypertension. METHODS: Using enzyme-linked immunosorbent assays, hemostatic measurements were obtained for women with pre-eclampsia (n=51), nonproteinuric hypertension of pregnancy (n=62), postpartum pre-eclampsia 24 h after childbirth (n=31), and no hypertension (healthy pregnant controls, n=100). RESULTS: There was a significant increase in circulating free TFPI levels in women with pre-eclampsia (9.7+/-6.2 ng/mL) or nonproteinuric hypertension of pregnancy (8.3+/-5.3 ng/mL) compared with healthy controls (5.3+/-2.1 ng/mL). In women with pre-eclampsia the levels remained elevated after placental delivery (10.6+/-4.0 ng/mL). Free protein S levels were significantly higher in women with pre-eclampsia (40.0%+/-10.7%), nonproteinuric hypertension of pregnancy (37.1%+/-12.5%), or postpartum pre-eclampsia (39.3%+/-9.1%) than in healthy pregnant controls (32.2%+/-8.5%). CONCLUSION: Increased levels of the physiologically active free forms of TFPI and free protein S, 2 coagulation inhibitors, may protect women with pregnancy-induced hypertension from the risks of hemostatic activation. 相似文献
68.
Sho Haneda M.D. Kouhei Fukushima M.D. Yuji Funayama M.D. Chikashi Shibata M.D. Ken-Ichi Takahashi M.D. Hitoshi Ogawa M.D. Munenori Nagao M.D. Kazuhiro Watanabe M.D. Iwao Sasaki M.D. 《Journal of gastrointestinal surgery》2006,10(7):1051-1059
Our previous studies demonstrated that sodium glucose cotransporter 1 (SGLT-1) was induced in the remnant ileum of total colectomized
rats via the action of factors other than hyperaldosteronism. The aim of the present study was to clarify whether fecal stream
is required for the enhancement of SGLT-1-mediated sodium transport. Twenty-seven pairs of ileal tissues were obtained from
the proximal and distal side, respectively, of loop ileostomy after total proctocolectomy. Mucosae were mounted in an Ussing
chamber to evaluate glucose-coupled sodium transport. Levels of SGLT-1 mRNA in proximal and distal mucosae were compared by
Northern blotting. Villous height and crypt depth were measured to test for correlations between mucosal structure and SGLT-1-mediated
sodium transport or mRNA expression levels. Both glucose-coupled sodium transport and expression of SGLT-1 mRNA were significantly
lower in distal mucosae relative to proximal mucosae. In distal mucosae, villous height, but not crypt depth, was significantly
lower than in proximal mucosae, demonstrating a positive correlation between villous height and SGLT-1 function and expression.
Comparative studies of proximal and distal mucosae demonstrated that in addition to hormonal changes, fecal stream is required
for full induction of the sodium transport system (which includes SGLT-1-mediated transport) in the remnant ileum following
total proctocolectomy.
Presented in part at the Forty-Sixth Annual Meeting of The Society for Surgery of the Alimentary Tract, Chicago, Illinois,
May 14–19, 2005 (poster presentation).
This work was supported by Grants-in-Aid for Scientific Research 10557118 and 14657295 from the Ministry of Education, Science
and Culture of Japan to K. Fukushima, and by Kanae Foundation to K. Fukushima. 相似文献
69.
目的探讨脑利钠肽(BNP)在评价功能性单心室患者行全腔静脉-肺动脉连接术(TCPC)后心功能中的价值及其意义。方法选择2004年4~11月间连续在我科随访的TCPC后患者11例(TCPC组),男7例,女4例;年龄8.2±4.1岁;随访时间2.1±1.6年。按照改良R oss标准对临床心功能评分。采集外周静脉血3m l,用酶标免疫法测定血浆BNP浓度。其中6例同期用磁共振成像(M R I)测定心功能,对BNP做相关因素分析。9人健康儿童作为正常对照(对照组)。结果(1)TCPC组血浆BNP水平为400pg/m l(IQR 200-690),较对照组的110 pg/m l(IQR 90-190)增高(P=0.003);(2)M R I测定结果:TCPC组6例患者舒张期末容量指数为65.76±8.65 m l/m2,收缩期末容量指数为31.90±6.36 m l/m2,心搏出量指数为39.09±11.76 m l/m2,射血分数(EF)为0.52±0.06,心脏指数(C I)为2.38±0.58 L/m in.m2,心肌质量指数为103.49±21.57 g/m2,心肌质量/心室舒张期末容量为1.57±0.24;(3)TCPC组BNP水平与手术时年龄呈明显正相关(r=0.632,P=0.041);BNP水平与上述M R I指标、R oss评分、性别、年龄、脉搏血氧饱和度(SpO2)及主心室类型等因素无关。结论TCPC后近2年神经内分泌系统仍处于应激状态,BNP增高可能与TCPC后特有的血流动力学状态有关;血浆BNP水平不能作为正确评估TCPC后心功能状态的指标。 相似文献
70.
目的比较使用桡动脉和乳内动脉全动脉化冠状动脉旁路移植术(CABG)与使用一根乳内动脉和静脉做常规CABG的近期手术结果。方法从1999年1月到2005年1月,阜外心血管病医院共有123例患者(男114例、女9例,年龄52.2±10.1岁)采用全动脉化CABG(全动脉化组),血管移植材料为乳内动脉和桡动脉,目标血管桥在2根以上;同期行常规CABG115例(男102例、女13例,年龄60.3±9.1岁),血管的移植材料为一根乳内动脉和若干静脉桥(常规手术组)。比较两组患者术前、术中和术后的临床结果。结果术前资料比较,全动脉化组的患者年龄更小,常规手术组3支病变患者较多(54.5%vs.86.1%,P=0.001),全动脉化组有更多患者选择非体外循环CABG(26.0%vs.57.4%,P=0.001);在体外循环CABG中,全动脉化组需要更长的手术时间;平均移植血管根数全动脉化组少于常规手术组(2.6±0.7根vs.3.4±0.9根,P=0.001);住院死亡率全动脉化组为0.8%,常规手术组为0.9%,两组比较差异无统计学意义(P=1.000);术后近期并发症发生情况两组结果相似。结论对选择适合的患者采用全动脉化CABG能够提供较为安全的近期手术结果。 相似文献