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41.
Background Intravitreal triamcinolone acetonide (TA) has been widely used as a therapeutic method for many ocular diseases, but a consensus on an appropriate safe therapeutic window of dosage for intravitreal injection, and whether vehicle of TA should be reduced or eliminated, has not yet been reached. The aim of this article is to investigate these issues.Methods Forty New Zealand white rabbits were divided into four experimental groups and one control group. Four or 25 mg TA, with vehicle either reduced or not, was injected into the vitreous cavity of rabbits in experimental groups. Rabbits in the control group received 0.2 ml intravitreal sterile saline solution. Intraocular pressures (IOP) were measured by a Tonopen tonometer. Values of lens density were measured by a Pentacam system. Soluble protein, total antioxidation capacity, reduced glutathione (GSH), glutathion peroxidase (GSH-px), and superoxide dismutase (SOD) in lens were measured by specific kits. ERG and pathological examinations, including light and electron microscopy of the retina, were also performed.Results Elevation of IOP was noted in all experimental groups after intravitreal TA (P<0.01, paired t-test). Significant increase of lens density was noticed at 1 week after intravitreal TA in the 25 mg vehicle-containing group (P<0.0001, paired t-test). Significant loss of GSH-px activity was noticed at the end of the study (P<0.05, paired t-test), while SOD activity increased (P<0.05, paired t-test). Amplitudes of ERG waves declined significantly in vehicle-containing groups (P<0.01, paired t-test) at the end of the study. Pathological examination showed obvious retinal toxicity in vehicle-containing groups.Conclusions Vehicle of TA should be eliminated or reduced before intravitreal injection to avoid potential retinal toxicity and transient increase in lens density.Presented at Chinese Academy of Fundus Disease Meeting, April, 2005.This study was supported by the 985 Fund of Peking University, Beijing.The authors have no financial interest in any instruments or drugs mentioned in this study.  相似文献   
42.
肱骨骨不连的手术治疗   总被引:4,自引:0,他引:4  
目的探讨肱骨骨不连的手术治疗方法及疗效。方法1998年12月~2005年5月共收治肱骨骨不连患者25例,均为肱骨骨折内固定术后发生骨不连,其中3例并发骨髓炎,6例合并不同程度肱骨骨缺损,骨缺损长度为3~6cm。骨不连病程8个月~5年。15例行吻合血管游离腓骨移植,10例采用加压交锁髓内针进行肱骨固定并辅以自体骨植骨。结果术后25例均得到随访,时间6个月~6年2个月。吻合血管游离腓骨移植组中移植的腓骨段均与肱骨干形成骨性愈合,平均骨性愈合时间为3.1个月;交锁髓内针组平均骨愈合时间为3.8个月。按Crates和Whittle肩肘关节功能评价标准,腓骨移植组:优9例,良4例,差2例;交锁髓内针组:优5例,良3例,差2例。结论应用加压交锁髓内针辅以自体骨移植对硬化性肱骨骨不连是一种有效的外科治疗方法;对合并骨髓炎、大段骨缺损及严重骨质疏松的肱骨骨不连,采用吻合血管游离腓骨移植可一期进行修复与重建。  相似文献   
43.
Early micromotion of implant components and periprosthetic bone loss in patients undergoing total knee arthroplasty are thought to contribute to late aseptic loosening. In the pursuit of longer implant survival, the administration of bisphosphonates may be advocated as a means to buffer implants against microinstability and periprosthetic bone loss. A bibliographic search identified one metaanalysis and two randomised controlled trials dealing with this topic. Current evidence supports the hypothesis that the inhibiting effects of bisphosphonates on bone resorption reduce implant micromotion and periprosthetic bone loss at the one-year follow-up. Tested bisphosphonates include clodronate, pamidronate and alendronate. However, a decline in periprosthetic BMD is observed at the three-year follow-up following a sixmonth course of bisphosphonate administration. Length of follow-up in available studies is currently too short to determine whether bisphosphonates increase the longevity of implants. Furthermore, the optimal dose, modality and length of bisphosphonate administration have yet to be determined.  相似文献   
44.
目的:探讨血管生成、细胞增殖指数、DNA倍性在胰腺导管癌发生、发展中的作用及临床意义。方法:对29例胰腺导管癌和7例慢性胰腺炎患者的石蜡包埋标本作苏木精鄄伊红(HE)染色,CD34、Ki67免疫组织化学染色,镜下计算微血管密度(MVD)及Ki67阳性细胞比例,同时用流式细胞仪(FCM)检测细胞核DNA倍性,计算异倍体出现率及S期比例,并结合临床病理资料对各项指标作相关分析。结果:胰腺导管癌和慢性胰腺炎都有较多的新生血管。MVD值在胰腺导管癌高、中、低分化3组之间差异无显著性。按肿瘤直径分为≤1.5cm、1.6~2.9cm、≥3cm3组,此3组间MVD值、Ki67阳性细胞百分率、DNA异倍体出现率及肿瘤周围有无浸润的差异都非常显著(P<0.01)。肿瘤越大,MVD值、Ki67阳性细胞百分率及DNA异倍体出现率越高。结论:胰腺导管癌的发生、发展伴血管生成和DNA合成增加,联合测定MVD、Ki67阳性细胞百分率、DNA倍型可能为胰腺导管癌临床预后预测提供辅助参考指标。  相似文献   
45.
目的观察大黄素和小剂量雌激素联合应用对去卵巢大鼠骨质疏松的预防作用.方法3月龄大鼠双侧卵巢去除术后预防用药90 d.用骨组织形态计量学方法,测定大鼠胫骨近端松质骨静态参数和动态参数,观察骨物理生长指标、血清生化指标和器官指数.结果大黄素90 mg·kg-1·d-1和己烯雌酚5 μg·kg-1·d-1联合应用可抑制去卵巢大鼠的破骨细胞活性,完全对抗其骨转化率增高和骨量丢失的骨质疏松症状,与己烯雌酚30 μg·kg-1·d-1的作用相当,且降低己烯雌酚对子宫和肝脏的刺激作用.结论大黄素和小剂量己烯雌酚联合应用可预防去卵巢大鼠骨质疏松.  相似文献   
46.
带浅静脉干逆行皮瓣早期微血管构筑变化的体视学研究   总被引:4,自引:0,他引:4  
目的 探讨带浅静脉干的逆行皮瓣早期微血管构筑变化的特点以供临床实践参考。方法 应用生物体视学技术测量带浅静脉干皮瓣微血管体积密度,结合组织学观察,与不带静脉干皮瓣作对照比较。结果 带浅静脉干皮瓣组微血管密度整体水平高于不带静脉干皮瓣组(P〈0.05)。结论 浅静脉干的存在有利于皮瓣的血管化进程,保留浅静脉干对皮瓣成活有利。  相似文献   
47.
Growth hormone (GH) is fundamental for the maintenance of bone mass and metabolism both during childhood and in adulthood. This effect is due to a complex interaction between circulating GH and IGF-I produced peripherally. In vitro data and experimental animal models have clarified many of the regulatory mechanisms underlying the characteristic skeletal changes occurring in acromegaly. This review focuses on the effects of GH excess on bone metabolism and mass in acromegalic patients and, in particular, on the influence of factors such as hypogonadism, gender, age and therapy on bone metabolism and arthropathy.  相似文献   
48.
手术治疗胸腰椎结核合并后凸畸形   总被引:7,自引:1,他引:6  
目的:探讨单切口双入路椎弓根系统内固定、后外侧植骨同期病灶清除、椎间植骨治疗胸腰椎结核合并后凸畸形的疗效。方法:对78例胸腰椎结核合并后凸畸形患者采用单切口双入路行后外侧植骨椎弓根系统内固定,同期病灶清除、椎间植骨治疗,观察患者症状及截瘫改善情况,后凸畸形矫正情况及植骨融合情况。结果:所有患者症状均明显改善,48例合并截瘫的患者中,25例完全恢复正常,7例ASIA分级改善1 ̄3级;植骨均在术后6个月 ̄1年融合,治愈率52.08%,好转率14.58%。后凸Cobb角平均矫正28.7°,随访1.4 ̄6.5年,平均2.6年,后凸角平均丢失2.9°。结论:单切口双入路后外侧椎弓根系统内固定同期病灶清除、椎间植骨可恢复脊柱的即刻稳定性,有利于植骨融合,后凸畸形矫正满意。  相似文献   
49.
肥胖者骨密度与体重及其他体成分关系的研究   总被引:3,自引:0,他引:3       下载免费PDF全文
目的肥胖易伴发多种慢性疾病。本文探讨肥胖者体重与体成份(脂肪、肌肉)之间的关系及其对临床减重的意义。方法经临床确诊系单纯性肥胖者45例,男17例,女28例。使用美国LunarDPX-L型双能X线吸收测量仪(DXA),测量全身骨、第2~4腰椎、股骨颈骨矿密度(BMD)及体脂肪和肌肉量,并计算体重指数(BMI=W/H2)、体重(kg)/身高(m)即W/H数值进行比较分析。结果男性体重平均94.54±17.41kg,BMI33±4.87。女性体重平均124.37±14.0kg,BMI35.41±6.39。男女两性全身BMD与体重相关,分别为r=0.415,P<0.05,r=0.529,P<0.0025。女性体重与脂肪、肌肉之间呈正相关分别为r=0.522,P<0.0025、r=0.612,P<0.005。男性体重与BMI、W/H及全身肌肉量相关,与脂肪组织无明显相关。男女性W/H较BMI相关系数高。男性全身BMD与全身肌肉量正相关r=0.421,P<0.05。女性全身及股骨颈BMD与脂肪量相关r=0.360,P<0.05、r=0.323,P<0.05。女性全身肌肉量与股骨颈BMD呈正相关r=0.373,P<0.05。结论①肥胖者体重增加,男性以肌肉增加为主,女性脂肪和肌肉都增加;②男性全身骨密度增高与肌肉量增加有关,而女性则主要为脂肪量增加;③女性肌肉、脂肪量与股骨颈BMD密切相关;④体重(kg)/身高(m)比计算体重指数能更准确地反映总体肥胖的程度。  相似文献   
50.
Introduction Patients with cystic fibrosis (CF) are known to be at risk for early osteoporosis, and the mechanisms that mediate bone loss are still being delineated. The aim of the present investigation was to investigate if a correlation exists in these patients between skeletal measurements by dual-energy x-ray absorptiometry (DXA) and two anabolic factors, dehydroepiandrosterone (DHEA) and insulin-like growth factor I (IGF-I), and proresorptive factors such as the cytokines interleukin-1β, tumor necrosis factor α, and interleukin-6. Methods We studied 32 outpatients (18 females; mean age: 26.2 ± 7.9 years) at a tertiary care medical center. The subjects had venous samples obtained, underwent anthropometric and bone mineral density (BMD) measurements, and completed a health survey. Serum IGF-I concentrations were below the age-adjusted mean in 78% of the participants, and DHEA sulfate (DHEAS) concentrations were low in 72%. Serum concentrations of all cytokines were on the low side of normal; nonetheless, there was a modest inverse correlation between IL-1β and BMD at all sites. Results In univariate analyses, IGF-I and DHEAS were significant correlates of BMD or bone mineral content. In final multivariate models controlling for anthropometric and other variables of relevance to bone density, only IGF-I was identified as a significant independent skeletal predictor. While alterations in DHEAS, IGF-I, and specific cytokines may contribute to skeletal deficits in patients with CF, of these factors a low IGF-I concentration appears to be most strongly correlated with BMD. Conclusions These findings may have therapeutic implications for enhancing bone density in these patients.  相似文献   
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