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排序方式: 共有1312条查询结果,搜索用时 15 毫秒
1.
目的探讨针刺干预对大鼠单眼视觉剥夺后视皮层方位柱“漂移”和通道重组的影响,初步阐明其作用机制。  相似文献   
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目的:建立较优的甘草质控成分(水分、总灰分、甘草苷、甘草酸)的近红外定量模型,实现快速检测。方法:基于2015年版《中国药典》方法测定97批甘草中水分、总灰分、甘草苷及甘草酸的含量。采用近红外光谱仪扫描其近红外光谱。采用R语言筛选最佳光谱预处理方法,建立近红外定量模型。结果:水分和甘草苷近红外定量模型的最佳预处理方法为一阶导数,其中水分测试集和验证集的相关系数分别为0.930 0和0.929 9,均方根误差分别为0.243 2和0.203 8,甘草苷测试集和验证集的相关系数分别为0.930 3和0.907 6,均方根误差分别为0.093 9和0.128 9;总灰分近红外定量模型的最佳预处理方法为MSC,测试集和验证集的相关系数分别为0.926 5和0.917 7,预测均方根误差分别为0.109 6和0.103 7;甘草酸近红外定量模型的最佳预处理方法为SNV,测试集和验证集的相关系数分别为0.918 1和0.915 7,预测均方根误差分别为0.274 8和0.236 0。结论:该研究建立了较优的甘草质控成分的近红外定量模型,其模型的准确度均较高,为实现快速检测奠定了基础。  相似文献   
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A growing body of research highlights the importance of cognition for prediction of falls in Parkinson's disease (PD). However, a previously proposed prediction model for future near falls and falls in PD, which includes history of near falls, tandem gait, and retropulsion, was developed without considering cognitive impairment. Therefore, by using a sample of 64 individuals with relatively mild PD and not excluding those with impaired cognition we aimed to externally validate the previously proposed model as well as to explore the value of additional predictors that also consider cognitive impairment. Since this validation study failed to support the proposed model in a PD sample including individuals with impaired global cognition, extended analyses generated a new model including dyskinesia (item 32 of Unified PD Rating Scale) and frontal lobe impairment (Frontal Assessment Battery—FAB) as significant independent predictors for future near falls and falls in PD. The discriminant ability of this new model was acceptable (AUC, 0. 80; 95% CI 0.68‐0.91). Replacing the continuous FAB scores by a dichotomized version of FAB with a cut‐off score ≤14 yielded slightly lower but still acceptable discriminant ability (AUC, 0. 79; 95% CI 0.68‐0.91). Further studies are needed to test our new model and the proposed cut‐off score of FAB in additional samples. Taken together, our observations suggest potentially important additions to the evidence base for clinical fall prediction in PD with concomitant cognitive impairment.  相似文献   
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Near‐infrared photoimmunotherapy (NIR‐PIT) is a molecularly targeted cancer phototherapy that is based on injecting a conjugate of a silicon‐phthalocyanine derivative, IRdye 700DX (IR700), and a monoclonal antibody that targets an expressed antigen on the cancer cell surface. Subsequent local exposure to NIR light results in the rapid and highly selective immunogenic cell death of targeted cancer cells. Because many cancers grow in bones through which light does not penetrate well, the goal of this study was to determine if NIR‐PIT can effectively treat cancers in bone. A bovine rib was used as a bone sample. Because the sample’s NIR light transmittance was shown to be approximately 4.52% in preliminary tests, it was hypothesized that a maximum radiation dosage of 128 and 1500 J/cm2 would be sufficient to induce cell death in in vitro target cells and in vivo mouse tumor models, respectively. Cell viability was measured through bioluminescence studies comparing relative luciferase activity, as well as a cytotoxicity assay. In the in vitro model, tumor cell viability was significantly decreased after 64 and 128 J/cm2 NIR light irradiation through the bone. An in vivo mouse tumor model also showed that 1500 J/cm2 NIR light irradiation through the bone significantly reduced tumor viability at both 24 and 48 hours posttreatment compared to the control group (P = .026 and .040 respectively). Therefore, despite limitations in light transmission, NIR‐PIT nevertheless is capable of effectively treating cancers within bone.  相似文献   
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Purpose of the study: the aim of this study was to synthesize PFC fNIRS outcomes on the effects of cognitive tasks compared to resting/baseline tasks in healthy adults from studies utilizing a pre/post design.

Material and methods: original research studies were searched from seven databases (MEDLINE, EMBASE, CENTRAL, CINAHL, SCOPUS, PEDro and PubMed). Subsequently, two independent reviewers screened the titles and abstracts followed by full-text reviews to assess the studies' eligibility.

Results: eleven studies met the inclusion criteria and had data abstracted and quality assessed. Methodology varied considerably and yet cognitive tasks resulted in the ΔO2Hb increasing in 8 of the 11 and ΔHHb decreasing in 8 of 8 studies that reported this outcome. The cognitive tasks from 10 of the 11 studies were classified as “Working Memory” and “Verbal Fluency Tasks”.

Conclusions: although, the data comparison was challenging provided the heterogeneity in methodology, the results across studies were similar.  相似文献   

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雷晓晴  王秀丽  李耿  付梅红  张秀荣  陈芳宁 《中草药》2019,50(16):3947-3954
目的应用近红外光谱(NIRS)技术结合偏最小二乘法(PLS)建立当归中多指标成分的快速无损检测方法,以更好地控制当归药材和饮片的质量。方法采集购买不同产地的当归样品共108批。建立同时测定当归中7种成分含量的超高效液相色谱(UPLC)方法,并以其测定值为参比;以积分球漫反射模式采集当归样品的NIRS图;采用PLS等化学计量学手段建立各指标性成分的参比值与NIRS图的定量校正模型。分别对建模过程的各个阶段进行优化,包括样本集的选择、不同预处理方法和不同光谱区段的选择。结果所建立的绿原酸、阿魏酸、异绿原酸A、藁本内酯、丁烯基苯肽、洋川芎内酯I和欧当归内酯A的模型校正集相关系数分别为0.937 6、0.970 2、0.963 4、0.991 1、0.962 4、0.966 6和0.947 6;预测均方差分别为0.072 1、0.038 9、0.011 3、0.483 0、0.017 5、0.178 0和0.097 0。NIRS模型预测值与UPLC测定值具有良好的线性相关关系,模型预测效果良好。结论采用NIRS技术结合PLS可以快速对当归中绿原酸、阿魏酸、异绿原酸A、藁本内酯、丁烯基苯肽、洋川芎内酯I和欧当归内酯A 7种成分的含量进行检测,方法操作简便、结果可靠。  相似文献   
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