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41.
A layer‐by‐layer approach is used to anchor small gold nanoparticles onto organic nanotubes resulting from the self‐assembly and polymerization of diacetylene‐containing nitrilotriacetic amphiphiles. The obtained nanotube–gold hybrid is used as a catalyst for the aerobic oxidation of various silanes. With minimal gold loading (0.05 mol%), all substrates are converted into the corresponding silanols with hydrogen gas as the only by‐product. The catalyst operates under mild conditions and can be easily recycled, losing neither activity nor selectivity.

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42.
In order that evidence‐based medicine can prevent “too much medicine”, it has to provide evidence in support of “gold standard” findings for use as diagnostic criteria, on which the assessment of other diagnostic tests and the outcomes of randomized controlled trials depend. When the results of such gold standard tests are numerical, cut‐off points have to be positioned, also based on evidence, to identify those in whom offering a treatment can be justified. Such a diagnosis depends on eliminating conditions that mimic the one to be treated. The distributions of the candidate gold standard test results in those with and without the required outcome of treatment are then used with Bayes rule to create curves that show the probabilities of the outcome with and without treatment. It is these curves that are used to identify a cut‐off point for offering a treatment to a patient and also to inform the patient's decision to accept or reject the suggested treatment. This decision is arrived at by balancing the probabilities of beneficial outcomes against the probabilities of harmful outcomes and other costs. The approach is illustrated with data from a randomized controlled trial on treating diabetic albuminuria with an angiotensin receptor blocker to prevent the development of the surrogate end‐point of “biochemical nephropathy”. The same approach can be applied to nonsurrogate outcomes such as death, disability, quality of life, relief of symptoms, and their prevention. Those with treatment‐justifying diagnoses such as “diabetic albuminuria” usually form part of a broader group such as “type 2 diabetes mellitus”. Any of these can be made the subject of evidence‐based differential diagnostic strategies.  相似文献   
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省、市、县三级实验室分别采用镜检法、胶体金法及巢式PCR法对泰安市2015-2019年输入性疟疾进行诊断与复核。共诊断与复核输入性疟疾病例122例,其中镜检法和胶体金法的符合率分别为94.3%(115/122)和95.9%(117/122),镜检阴性率为5.7%(7/122),均为恶性疟;胶体金法阴性率为4.1%(5/122),3例非恶性疟和2例恶性疟阴性,3种检验方法符合率差异有统计学意义(P <0.05)。其中恶性疟和间日疟诊断符合率最高,均达100%,对卵形疟诊断符合率最低,仅为12/18,对4种疟原虫实验室诊断符合率差异有统计学意义(P <0.01)。医疗机构中初诊合格率为94.3%(115/122),市、县级疾病预防控制机构复核合格率分别为97.5%(119/122)和95.1%(116/122),差异无统计学意义(P> 0.05)。今后应继续加强市、县级疟疾实验室镜检人员技能培训,积极开展疟疾核酸检测,以进一步提升医疗及疾病预防控制机构的疟疾诊断水平。  相似文献   
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=O4 探讨结核感染T细胞斑点试验(T-cell spot of Tuberculosis,T-SPOT.TB)在手、腕部腱鞘结核诊断中的临床应用价值。方法通过对2012年1月至2018年1月我院收集 64例怀疑手、腕部腱鞘结核临床资料进行回顾性分析,根据病理诊断及临床表现判断有无结核分枝杆菌感染;全部病例均经过T-SPOT.TB和胶体金标法分别进行体外γ-干扰素释放试验和血清结核抗体检测,采用Kappa、χ2检验进行统计学分析。-结果- 共收集分析相关病例64例,其中诊断为手、腕部腱鞘结核(结核病例)21例,非手、腕部腱鞘结核(非结核病例)43例。经T-SPOT.TB检测,结核病例阳性者20例,非结核病例阴性者40例,灵敏度为95.2%,特异度为93.0%,阳性预测值为87.6%,阴性预测值为97.6%。经胶体金标法检测血清结核抗体,结核病例阳性者5例,非结核病例阴性者37例,灵敏度为23.8%,特异度为86.0%,阳性预测值为45.4%,阴性预测值为69.8%。与临床诊断比较,T-SPOT.TB和胶体金标法的Kappa值分别为0.862和0.112,T-SPOT.TB比胶体金标法具有更好的一致性,且灵敏度、阳性预测值和阴性预测值均明显更高,差异有统计学意义(P<0.05)。-结论- T-SPOT.TB在手、腕部腱鞘结核诊断中具有良好的辅助诊断价值。  相似文献   
47.
This article provides a perspective on the challenges of appropriate glucose measurement in the context of glucose clamp experiments. In a first step, the core outcome parameters of a clamp experiment, the blood glucose target level, and the glucose infusion rate will be identified. The relation of these core parameters to glucose measurement are discussed. From there, the core quality parameters of glucose measurement within a clinical research setting are identified and assessed in light of their practical implications, with a specific consideration of the work presented by Cohen et al. in this issue of the Journal of Diabetes Science and Technology.  相似文献   
48.
Summary Blood insulin, blood glucose and the biosynthesis and release of insulin have been studied in mice made obese with a single injection of gold thioglucose. In such mice, blood glucose levels were normal, though serum insulin rose in parallel with the development of obesity. When compared with controls, insulin secretion and synthesis were increased in isolated islets of Langerhans from obese mice, over a wide range of glucose concentrations. However, in obese animals, insulin biosynthesis was augmented above control levels at 2 mmol/l glucose, whilst the increase in insulin secretion accompanying obesity only became evident at glucose concentrations > 5 mmol/l. After 2 min incubation, cyclic AMP rose more in islets from obese mice than in controls, though cyclic AMP levels did not significantly differ in either group after 10 min incubation with glucose. Glucose oxidation was also increased in islets of Langerhans from obese mice. It seems possible that changes in glucose oxidation, as well as in cyclic AMP levels, contribute to the alteration in the B cell response in this type of obesity.  相似文献   
49.
The aim of the present work is to study the role of the different forces involved in the agglutination of immune γ-globulin (IgG) covered latex particles due to antigen-antibody reaction. An experimental investigation on the adsorption of IgG molecules on three latexes with different surface charge densities is described. Photon correlation spectroscopy was used to determine the hydrodynamic layer thickness of the IgG molecules adsorbed on the latexes. In order to get an insight into the forces acting between two antibody-covered particles approaching each other, the colloidal stability and immunoreactivity of these biocomplexes were studied. They can be stabilized by electrostatic or hydration forces. The immunological agglutination of IgGimmobilized latex particles due to the addition of the antigen was quantified through scattered light intensity measurements. The immunoresponse increases with ionic strength of the medium until a maximum value is achieved. Above this maximum, the immunoreactivity decreases.  相似文献   
50.
目的:评价酶联免疫法和胶体金法用于肺炎衣原体IgM抗体(CP-IgM)检测抗干扰能力的差异。方法:检测方法的优劣一定程度上源于该方法抗干扰能力的强弱,体现在准确率、敏感性、特异性等相关指标上,选取219例临床疑为肺炎衣原体感染患者血清作为研究样本,分别采用酶联免疫法和胶体金法检测肺炎衣原体IgM抗体。比较两种方法检测结果的真阳性例数、真阴性例数、假阳性例数、假阴性例数,并计算两种方法相应的准确率、敏感性、特异性,进而评价两种检测方法的抗干扰能力。结果:酶联免疫法检测肺炎衣原体IgM抗体比胶体金法的真阳性例数与真阴性例数多;而假阳性例数和假阴性例数均少;酶联免疫法的准确率、敏感性、特异性均高于胶体金法(P<0.05)。结论:酶联免疫法检测肺炎衣原体IgM抗体的抗干扰能力比胶体金法更强,检测结果准确性更高。  相似文献   
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