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61.
The rubric complementary medicine covers a variety of approaches that may seem alike only in their being outside conventional care and training. We have asked experienced practitioners to present their own pieces of this jigsaw, realising that these clinical fragments, when seen together, create excitement but also confusion. Of course, this forum is not intended to be a comprehensive review of relevant complementary treatments, and often the individual apporaches to clinical problems will appear totally unrelated, while their apparent effectiveness stretches the biomedical model and conventional research methodology beyond their capacity. With this in mind, we intend that forthcoming articles and reviews will expand on the therapies themselves, and discuss the evidence supporting them.  相似文献   
62.
结合当前国内外尿液分析的发展现状和目前国内常规检验工作忽视尿有形成分检查的错误倾向,笔者参考国家(际)标准、文献及本人的临床实践、科研成果,阐述了尿液有形成分检查的临床价值、标准检验流程,评论了应用各种仪器进行镜检筛选的优点与不足,并对如何加强我国尿液分析的质最管理提出了见解.  相似文献   
63.
Guidelines recommend that patients with COPD are stratified arbitrarily by baseline severity (FEV1) to decide when to initiate combination treatment with a long-acting β2-agonist and an inhaled corticosteroid. Assessment of baseline FEV1 as a continuous variable may provide a more reliable prediction of treatment effects. Patients from a 1-year, parallel-group, randomized controlled trial comparing 50 μg salmeterol (Sal), 500 μg fluticasone propionate (FP), the combination (Sal/FP) and placebo, (bid), were categorized post hoc into FEV1 <50% and FEV1 ≥50% predicted subgroups (n=949/513 respectively). Treatment effects on clinical outcomes – lung function, exacerbations, health status, diary card symptoms, and adverse events – were investigated. Treatment responses based on a pre-specified analysis explored treatment differences by severity as a continuous variable. Lung function improved with active treatment irrespective of FEV1; Sal/FP had greatest effect. This improvement appeared additive in milder disease; synergistic in severe disease. Active therapy significantly reduced exacerbation rate in patients with FEV1 <50% predicted, not in milder disease. Health status and breathlessness improved with Sal/FP irrespective of baseline FEV1; adverse events were similar across subgroups. The spirometric response to Sal/FP varied with baseline FEV1, and clinical benefits were not restricted to patients with severe disease. These data have implications for COPD management decisions, suggesting that arbitrary stratifications of baseline severity are not necessarily indicative of treatment efficacy and that the benefits of assessing baseline severity as a continuous variable should be assessed in future trials.  相似文献   
64.
Objective To compare the effects of 2 vascular carriers, arteriovenous loop and arteri-ovenous bundle, on inducing angiogenesis in coral scaffold of vascularized tissue-engineered bone in animal models.Methods Thirty-six adult male New Zealand rabbits were randomized into 2 even groups.In group A, an arteriovenous loop (AVL) was formed by microsurgical anastomosis at the proximal ends between the femoral poptiteal artery and vein, and placed in the circular side groove of the coral block (6 mm × 8 mm × 10 mm) .In group B, flow-through vessels bundles of both femoral artery and vein were placed in the side grooves of the coral block.All the implants in 2 groups were wrapped by a micro-porous expand-ed-polytetrafluoroethylene (ePTFE) membrane, and fixed subcutaneously by suturing.Evaluation methods included gross morphological observations, histological examinations, India ink perfusion and vascular casting after 2, 4, 6 weeks.The density of blood vessels was analyzed by the statistical software SPSS 10.0.Results All the corals were encased by newly formed fibrovascular tissues in 2 groups.Ink-stained vessels distributed the surfaces and side grooves, and invaded the interspaces of corals.The degree of vascularization increased over the course of experiment.Blood vessel density demonstrated a significant continuous increase between 2 and 6 weeks after implantation in group A.The mean value of blood vessel density in group A (2 weeks 276.60±4.67, 4 weeks 517.20±10.66, 6 weeks 707.00 ±11.87) was significantly higher than in group B (2 weeks 153.60 ±7.16, 4 weeks 269.40±6.80, 6 weeks 279.20±6.53) (P <0.01).Vascular casting showed that in group A, significant blood vessels sprouted from all areas of the loop, espe-cially at the entrance of the arteriovenous pediele where the small tubes were densely interconnected.In group B, however, no blood vessels sprouted from the arteriovenous bundles and only some small vessels grew from the entrance and exit.Conclusions A vascularized coral model can be constructed by inserting an ar-teriovenous loop or an arteriovenous bundle, useful in vascular bone tissue engineering.The former, however, have stronger abilities to induce angiogenesis than the latter.  相似文献   
65.
Calculations of radiation flux and dose distributions for boron neutron capture therapy (BNCT) of brain tumors are typically performed using sophisticated three-dimensional analytical models based on either a homogeneous approximation or a simplified few-region approximation to the actual highly heterogeneous geometry of the irradiation volume. Such models should be validated by comparison with calculations using detailed models in which all significant macroscopic tissue heterogeneities and geometric structures are explicitly represented as faithfully as possible. This paper describes such a validation exercise for BNCT of canine brain tumors. Geometric measurements of the canine anatomical structures of interest for this work were performed by dissecting and examining two essentially identical Labrador retriever heads. Chemical analyses of various tissue samples taken during the dissections were conducted to obtain measurements of elemental compositions for the tissues of interest. The resulting geometry and tissue composition data were then used to construct a detailed heterogeneous calculational model of the Labrador head. Calculations of three-dimensional radiation flux distributions pertinent to BNCT were performed for this model using the TORT discrete-ordinates radiation transport code. The calculations were repeated for a corresponding volume-weighted homogeneous-tissue model. Comparison of the results showed that peak neutron and photon flux magnitudes were quite similar for the two models (within 5%), but that the spatial flux profiles were shifted in the heterogeneous model such that the fluxes in some locations away from the peak differed from the corresponding fluxes in the homogeneous model by as much as 10%-20%. Differences of this magnitude can be therapeutically significant, emphasizing the need for proper validation of simplified treatment planning models.  相似文献   
66.
Twelve patients with metastatic colon cancer were treated with 131I-chimeric B72.3 (IgG-4) at total doses of 28 or 36 mCi/m2 in two or three weekly fractions. Bone marrow suppression was the only significant side effect. The degree of bone marrow suppression adjusted for whole-body dose was modestly but statistically significantly (p = 0.04) less than that seen with identical doses given as a single infusion for the total dose of 36 mCi/m2. Nine of twelve patients developed an antibody response to ch B72.3, which altered the kinetics of radiolabeled antibody in four patients given a second course of therapy. One patient had a minor response that lasted 4 mo. Fractionation of this particular radiolabeled antibody at the dose schedule used produced a modest increase in the therapeutic window in regard to administered dose.  相似文献   
67.
Six cases were examined to review the important anaesthetic implications of Larsen's syndrome. Potential problems arising in these patients are highlighted and emphasis placed on cervical spine and airway/respiratory management.  相似文献   
68.
目的:制备脑干缺血动物模型并观察大鼠脑干缺血后早期组织学病理的超微结构。方法:应用两点电凝基底动脉的方法制作鼠脑干缺血动物模型。结果:病理学观察发现脑干缺血2小时即可出现超早期病理变化,并随时间的延长缺血性损害逐渐加重。结论:两点电凝基底动脉后可以造成稳定的脑干缺血,对急性脑干缺血的病理学研究有一定的价值。  相似文献   
69.
目的评价血清铁参数与高血胆固醇症(HCL)病人心肌灌注、室壁运动异常及血管造影显示的冠状动脉疾病(CAD)程度的相互关系.方法选择38名具有高血胆固醇症(LDL-C>3.38mmol/L)从未治疗过的男性病人(平均年龄59±6岁)作为HCL组和32名年龄匹配而胆固醇水平正常(NCL)的男性为NCL组,进行冠状动脉造影并在10d内行SPECT检查,应用99mTc-甲氧基异丙基异氰(MIBI)进行静息/负荷门控断层心肌灌注显像、室壁运动功能图像分析;同时测定血清铁参数、血脂及常规血液学参数.结果在HCL组发现血清铁蛋白(SF)与心肌灌注系数(r=0.70,P<0.01),可逆系数(r=0.66,P<0.01)和室壁运动系数(r=0.53,P<0.05)之间呈显著性相关;而总铁结合力与灌注系数之间呈一弱(负)相关(r=-0.52,P<0.05).在NCL组铁参数与灌注系数及室壁运动系数之间无显著性相关.多元回归分析证实血清铁蛋白水平是决定HCL病人中心肌灌注的独立因素(β=0.55,P>0.05).铁参数与两组通过冠状动脉造影(CAG)进行评分所定义的CAD程度无关.结论体内铁贮水平升高与HCL病人心肌灌注和功能异常的严重性和程度有着密切的关系,但与CAD的造影显示的病变范围无关.血清铁蛋白水平增高,可增加铁介导的氧化应力和LDL过氧化作用,导致HCL相关的血管内皮功能紊乱并进一步损伤心肌灌注和室壁运动功能.  相似文献   
70.
远端蒂筋膜皮瓣内浅静脉干定时放血的临床应用   总被引:3,自引:1,他引:2  
[目的]探讨预防远端蒂筋膜皮瓣静脉危象和提高皮瓣成活质量的方法. [方法]通过于26例大面积下肢皮神经营养血管远端蒂筋膜皮瓣内浅静脉干远心端蒂部结扎,近心端留置静脉留置针外引流,每天6 h定量放血,连续5d,密切观察皮瓣血供及肿胀情况. [结果]26例皮瓣全部成活,无1例出现静脉危象,无明显肿胀期.随访1~2年,皮瓣质地柔软,无明显色素沉着,均恢复保护性感觉. [结论]此方法能预防远端蒂筋膜皮瓣的静脉危象,提高皮瓣的成活质量.  相似文献   
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