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81.
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
82.
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
83.
目的:研究乙肝后肝硬化患者消化性溃疡的临床特点及治疗转归,探讨内镜下止血及小剂量心得安对肝源性溃疡愈合的影响。方法:肝源性溃疡75例,观察其发病年龄、临床表现、溃疡部位、HP感染率、出血率及7d内止血率及溃疡愈合率等特点,随机分为治疗组37例,内镜下止血 心得安 泰胃美治疗,对照组38例,用维生素B6 泰胃美治疗;另外选单纯性消化性溃疡73例,随机对照2组36例,用维生素B6 泰胃美治疗,对照3组37例,内镜下止血 维生素B6 泰胃美治疗。结果:肝源性溃疡发病年龄较单纯性消化性溃疡晚10年,溃疡部位以复合性溃疡居多和并出血率高,内镜下止血 小剂量心得安可明显提高肝源性溃疡7d内止血率,促进肝源性溃疡愈合率,与对照组具有统计学意义(P<0.01)。结论:肝源性溃疡难以治愈互易并出血,互以复合性溃疡多见,门静脉高压因素可能从中发挥作用,内镜下注射及喷洒止血剂及口服小剂量心得安及用制酸护肝治疗能有效止血,促进溃疡的愈合。 相似文献
84.
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
85.
86.
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
87.
三七总皂甙(PNS)能抑制心肌总ATP酶活力,但对Na~( )-K~( )-ATP酶无明显影响。三七皂甙单体Rb_1及Rg_1对心肌总ATP酶活力均有抑制作用,但Rb_1的抑制效力显著大于Rg_1·Rb_1能抑制豚鼠离体心房肌的自律性和收缩性,Rg_1也能抑制豚鼠离体心房肌的自律性,但对心房肌的收缩性却无明显影响。提示PNS抑制心肌收缩力这一作用的主要有效成份是Rb_1· 相似文献
88.
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
89.
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
90.
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