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71.
目的:观察菱形孔隙及方形孔隙两种不同几何形状多孔层设计股骨柄假体的生物学固定效果,分析孔隙几何形状对假体生物学固定的影响。方法:于2003-03/2004-04在中山大学医学部动物中心完成全部实验过程。纳入24只成年杂种犬,雌雄不拘,以随机数字表法均分为2组,即菱形孔隙组及方形孔隙组,各12只。自行设计完成犬骨重建型股骨柄假体,将股骨柄假体近2/3段表层改成两种不同几何形状的粗大多孔层结构,钛丝表面假体,钛丝直径改为1.0mm,孔径加大至5.0mm,孔隙度可达80%。菱形孔隙组钛丝沿股骨假体柄呈螺旋形排列并斜形相交,方形孔隙组钛丝沿股骨假体柄纵横排列并直角相交。均将假体表面孔隙内充填自体股骨头颈骨质制成的骨泥后,行右侧人工股骨头置换术。术后6个月行X射线摄片、组织学检查及生物力学测试,以股骨近端骨吸收情况、新生骨长入深度及孔隙充满度、假体-骨界面最大剪切强度测量为评价指标,了解假体内外成骨和固定情况。结果:菱形孔隙组及方形孔隙组各12只,实验中手术不成功或术后生存不够观察时间的均予实验过程中随时补足,最终每组12只进入结果分析。①组织学观察显示菱形孔隙组多孔层孔隙内最大骨长入深度及孔隙内新生骨平均充盈率均优于方形孔隙组(3000,2450μm;96.2%,71.6%)。②菱形孔隙组假体-骨界面最大剪切强度高于方形孔隙组,差异有显著性意义[(8.57±0.51),(3.15±0.41)N/mm2,P<0.01]。③菱形孔隙组6个月标本肉眼及X射线观察股骨近端无明显骨吸收,优于方形孔隙组;所有实验犬术后伤口缝线任其自行脱落,除1只伤口感染并于术后17d死亡外,余实验犬均伤口愈合良好,未出现不良反应。结论:股骨柄假体表面不同几何形状多孔层设计能影响其生物学固定效果,菱形孔隙设计优于方形孔隙。 相似文献
72.
Frates MC Benson CB Charboneau JW Cibas ES Clark OH Coleman BG Cronan JJ Doubilet PM Evans DB Goellner JR Hay ID Hertzberg BS Intenzo CM Jeffrey RB Langer JE Larsen PR Mandel SJ Middleton WD Reading CC Sherman SI Tessler FN 《Ultrasound quarterly》2006,22(4):231-8; discussion 239-40
The Society of Radiologists in Ultrasound convened a panel of specialists from a variety of medical disciplines to come to a consensus on the management of thyroid nodules identified with thyroid ultrasonography (US), with particular focus on which nodules should be subjected to US-guided fine needle aspiration and which thyroid nodules need not be subjected to fine-needle aspiration. The panel met in Washington, DC, October 26-27, 2004, and created this consensus statement. The recommendations in this consensus statement, which are based on analysis of the current literature and common practice strategies, are thought to represent a reasonable approach to thyroid nodular disease. 相似文献
73.
Solid organ transplantation has shown improvement in patient and graft survival rates due to the development of immunosuppression in the last fifty years; however only the last two decades led to the development of new, baseline immunosuppressive drugs that avoid the unlikely side effects of calcineurin inhibitors, especially nephrotoxicity. The transplanted organ is foreign to the host and, therefore, it induces a complex immune response of the recipient. In this review, a brief outline of immune response is given, followed by the introduction of new immunosuppressive drugs acting via variant pathways. These are compounds which are already in use or becoming shortly available and are potential future alternatives for the calcineurin inhibitors. This paper highlights the role of co-stimulation blockade with belatacept and the recently even more intensively studied field of tolerance induction. 相似文献
74.
Background
There is little information available to inform choice of technique for appendiceal stump control in pediatric laparoscopic appendectomy (LA). We compared complications (stump leak, intra-abdominal abscess formation [IAA], surgical site infection [SSI]) in children undergoing LA for perforated (PA) and nonperforated appendicitis (NPA) by technique of appendiceal stump control.Methods
All children who underwent LA for confirmed acute appendicitis between 2006 and 2009 were reviewed. Choice of stump control (endoloop [EL] or endostapler [ES]) was determined by surgeon preference. Interactions between stump closure techniques and other potential confounders (intra-abdominal drain, irrigation, different antibiotic regimens) were explored using a logistic regression model.Results
Of 242 patients undergoing LA, 57 (23.6%) had PA. In the PA group the appendiceal stump was closed with EL in 47 (82.5%) patients, while in the NPA group EL was used in 161 (87%) patients. Among PA patients, IAA was more common in the ES than the EL group (5 of 10 [50%] v. 6 of 47 [12.7%]). There was no significant difference in rates of SSI. Among NPA patients, there were no differences in rates of IAA or SSI. There were no stump leaks in either group. Logistic regression analysis confirmed the predictive effect of ES use on IAA formation in PA (adjusted odds ratio 7.09; 95% confidence interval 1.08–46.13; p = 0.042).Conclusion
Our data suggest that in most cases of PA, the appendiceal stump can be safely controlled with EL. Within the PA group, the higher rates of IAA seen in ES patients may be attributable to the quality of the appendiceal stump rather than the technique of closure. 相似文献75.
BackgroundAbdominal wall defects in children are not always amenable to primary repair and may require a patch. The ideal material has yet to be established. We sought to evaluate our experience using the bioabsorbable material Surgisis (Cook Surgical, Bloomington, IN) for abdominal closure.MethodsA retrospective chart review of abdominal wall defects repaired with Surgisis in our institution from 2000 to 2010 was performed. Data extracted included cause of defect, age at operation, possibility of skin coverage, recurrence, length of follow-up, and rate of wound infection.ResultsThirteen patients were identified. Cause of defect was gastroschisis (n = 2), ventral hernia after diaphragmatic hernia repair (n = 2), and omphalocele (n = 9). At median follow-up of 60 months (range, 10-90), 5 (38%) of 13 patients recurred, and 1 patient recurred twice. All recurrences required subsequent patch closure. Six instances of wound infection required antibiotics. None required patch removal. There was a trend toward more frequent recurrence among infants undergoing patch repair (3/4 recurrences in this group) than neonates (1/4 recurrences) or children older than 18 months (1/5 recurrences).ConclusionOur data suggest that Surgisis is moderately successful in the repair of pediatric abdominal wall defects. We noted a trend toward a higher recurrence rate in infants. Further studies investigating timing of repair and alternative biosynthetic materials are warranted. 相似文献
76.
Background/PurposeMost surgeons recommend daily dilatation after surgery for Hirschsprung disease and anorectal malformations. Our goal was to critically evaluate the potential risks and benefits of this practice.MethodsA retrospective chart review was carried out of all children undergoing repair of Hirschsprung disease or anorectal malformation over 5 years. Patients with long segment Hirschsprung disease or anal stenosis were excluded.ResultsThere were 95 patients, of which 34 had Hirschsprung disease and 61 had an anorectal malformation. Postoperatively, 65 underwent routine dilatation by parents; and 30 underwent weekly calibration by the surgeon, with daily dilatation by the parents only if the anastomosis was felt to be narrow. Of the 30 children undergoing weekly calibration, only 5 (17%) developed late narrowing that required conversion to the daily parental dilatation approach. There were no significant differences between the 2 approaches with respect to stricture development, anastomotic disruption, perineal excoriation, or enterocolitis.ConclusionWeekly calibration by the surgeon is associated with similar outcomes to daily dilatation by the parents. Because this approach is kinder to the parents and the child, it should be seriously considered for the postoperative management of children with Hirschsprung disease or anorectal malformations. 相似文献
77.
H Van Remoortel S Giavedoni Y Raste C Burtin Z Louvaris E Gimeno-Santos D Langer A Glendenning NS Hopkinson I Vogiatzis BT Peterson F Wilson B Mann R Rabinovich MA Puhan T Troosters 《The international journal of behavioral nutrition and physical activity》2012,9(1):84
ABSTRACT: The assessment of physical activity in healthy populations and in those with chronic diseases is challenging. The aim of this systematic review was to identify whether available activity monitors (AM) have been appropriately validated for use in assessing physical activity in these groups. Following a systematic literature search we found 134 papers meeting the inclusion criteria; 40 conducted in a field setting (validation against doubly labelled water), 86 in a laboratory setting (validation against a metabolic cart, metabolic chamber) and 8 in a field and laboratory setting. Correlation coefficients between AM outcomes and energy expenditure (EE) by the criterion method (doubly labelled water and metabolic cart/chamber) and percentage mean differences between EE estimation from the monitor and EE measurement by the criterion method were extracted. Random-effects meta-analyses were performed to pool the results across studies where possible. Types of devices were compared using meta-regression analyses. Most validation studies had been performed in healthy adults (n = 118), with few carried out in patients with chronic diseases (n = 16). For total EE, correlation coefficients were statistically significantly lower in uniaxial compared to multisensor devices. For active EE, correlations were slightly but not significantly lower in uniaxial compared to triaxial and multisensor devices. Uniaxial devices tended to underestimate TEE (12.07 (95%CI; -18.28 to 5.85) %) compared to triaxial (6.85 (95%CI; -18.20 to 4.49) %, p = 0.37) and were statistically significantly less accurate than multisensor devices (3.64 (95%CI; -8.97 to 1.70) %, p<0.001). TEE was underestimated during slow walking speeds in 69% of the lab validation studies compared to 37%, 30% and 37% of the studies during intermediate, fast walking speed and running, respectively. The high level of heterogeneity in the validation studies is only partly explained by the type of activity monitor and the activity monitor outcome. Triaxial and multisensor devices tend to be more valid monitors. Since activity monitors are less accurate at slow walking speeds and information about validated activity monitors in chronic disease populations is lacking, proper validation studies in these populations are needed prior to their inclusion in clinical trials. 相似文献
78.
79.
Barry PM Gardner TJ Funk E Oren E Field K Shaw T Langer AJ 《Emerging infectious diseases》2012,18(1):113-116
In 2008, diagnosis and investigation of 2 multidrug-resistant tuberculosis cases with matching genotypes led to identification of an outbreak among foreign-born persons who performed short-term seafood production work in Alaska during 2006. Tuberculosis control programs should consider the possibility of domestic transmission even among foreign-born patients. 相似文献
80.