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51.
正Cadmium(Cd), a toxic heavy metal commonly found in the environment, can cause toxic reactions at a dose of 30 mg. Cd is absorbed into the body mainly through the respiratory tract, digestive tract, 相似文献
52.
目的 采用Meta分析对比四维子宫输卵管超声造影(4D-HyCoSy)与子宫输卵管造影(HSG)评估输卵管通畅性的效能。方法 系统搜索PubMed、Cochrane Library、Embase、Web of Science、中国生物医学文献数据库、中国知网、万方医学网及维普数据库中建库至今有关4D-HyCoSy和/或HSG评估输卵管通畅性的文献。由2名研究人员依据纳入标准和排除标准筛选文献并提取信息;分别计算4D-HyCoSy和HSG评估输卵管通畅性的合并敏感度(SEN)、特异度(SPE)及诊断比值比(DOR),绘制综合受试者工作特征(SROC)曲线,获得曲线下面积(AUC),并以Medcalc 19.1.1统计软件比较AUC。结果 最终纳入19篇文献、1 358例疑似输卵管因素导致不孕患者,其中4篇同时采用4D-HyCoSy及HSG评估输卵管通畅性,10篇仅以4D-HyCoSy评估,5篇仅以HSG评估。Meta分析结果显示,4D-HyCoSy评估输卵管通畅性的合并SEN、SPE及DOR分别为0.92[95%CI(0.91,0.94)]、0.91[95%CI(0.89,0.93)]及115.06[95%CI(54.23,224.10)];HSG评估输卵管通畅性的合并SEN、SPE及DOR分别为0.84[95%CI(0.81,0.87)]、0.80[95%CI(0.76,0.83)]及28.64[95%CI(10.08,81.35)]。4D-HyCoSy评估输卵管通畅性的AUC为0.98[95%CI(0.96,0.99)],HSG为0.93[95%CI(0.90,0.95)],差异有统计学意义(Z=6.97,P<0.01)。结论 4D-HyCoSy评估输卵管通畅性的效能高于HSG。 相似文献
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55.
目的 探讨甲状腺癌根治术中不同途径显露喉返神经的应用情况.方法 根据随机数字表法将92例进行甲状腺癌根治术的患者随机分为对照组和观察组,每组46例.对照组采用甲状腺下动脉途径法显露喉返神经,观察组采用甲状腺最下动脉途径法显露喉返神经.比较两组患者寻找喉返神经的时间、术中出血量、手术时间、术后声音嘶哑和喉返神经损伤的发生率.结果 观察组患者寻找喉返神经的时间和手术时间均明显短于对照组患者,差异均有统计学意义(P﹤0.01).观察组患者的术中出血量明显少于对照组患者,差异有统计学意义(P﹤0.01).观察组患者术后声音嘶哑和喉返神经损伤的发生率均低于对照组患者,差异均有统计学意义(P﹤0.05).结论 甲状腺癌根治术中应用不同途径显露喉返神经,其效果存在差异.与甲状腺下动脉途径法相比,甲状腺最下动脉途径法能够明显缩短寻找喉返神经的时间和手术时间,减少术中出血量,降低术后声音嘶哑和喉返神经损伤的发生率,值得临床推广应用. 相似文献
56.
Yi Li Ying Chen Xiang Li Jian Wu Jing-Ying Pan Ri-Xin Cai Ri-Yun Yang Xiao-Dong Wang 《中国神经再生研究》2019,(9)
In the search for a therapeutic schedule for spinal cord injury, it is necessary to understand key genes and their corresponding regulatory networks involved in the spinal cord injury process. However, ad hoc selection and analysis of one or two genes cannot fully reveal the complex molecular biological mechanisms of spinal cord injury. The emergence of second-generation sequencing technology(RNA sequencing) has provided a better method. In this study, RNA sequencing technology was used to analyze differentially expressed genes at different time points after spinal cord injury in rat models established by contusion of the eighth thoracic segment. The numbers of genes that changed significantly were 944, 1362 and 1421 at 1, 4 and 7 days after spinal cord injury respectively. After gene ontology analysis and temporal expression analysis of the differentially expressed genes, C5ar1, Socs3 and CCL6 genes were then selected and identified by real-time polymerase chain reaction and western blot assay. The mRNA expression trends of C5ar1, Socs3 and CCL6 genes were consistent with the RNA sequencing results. Further verification and analysis of C5ar1 indicate that the level of protein expression of C5ar1 was consistent with its nucleic acid level after spinal cord injury. C5ar1 was mainly expressed in neurons and astrocytes. Finally, the gene Itgb2,which may be related to C5ar1, was found by Chilibot database and literature search. Immunofluorescence histochemical results showed that the expression of Itgb2 was highly consistent with that of C5ar1. Itgb2 was expressed in astrocytes. RNA sequencing technology can screen differentially expressed genes at different time points after spinal cord injury. Through analysis and verification, genes strongly associated with spinal cord injury can be screened. This can provide experimental data for further determining the molecular mechanism of spinal cord injury, and also provide possible targets for the treatment of spinal cord injury. This study was approved ethically by the Laboratory Animal Ethics Committee of Jiangsu Province, China(approval No. 2018-0306-001) on March 6, 2018. 相似文献
57.
知识点模块网格化模型在肾内科实习生带教中的应用 《医学教育管理》2019,5(1):34-37
目的 运用知识点模块网格化构建带教模型,观察其在肾内科实习生中的应用效果。方法 根据《内科学》(第八版)肾内科教学大纲要求,结合肾内科病房常见病、多发病的临床特点,精心挑选相关知识点,以理论为支撑点,以服务于实习带教工作为靶目标,各个知识点之间有临床的关联性,最终形成网格化的诊治分
析模型。将血尿、蛋白尿、高血压、水肿、肾小球滤过率为切入点,设定肾病综合征、系统性红斑狼疮、糖尿病肾病和急、慢性肾功能衰竭为临床知识必须掌握点,从病史、症状、体征和实验室检查几方面来培养实习生的诊疗思维,并通过知识点来关联疾病的诊治,从而帮助他们在有限的肾内科实习期间尽可能掌握肾内科临床知识。结果 本研究开展一年以来,对于来肾内科轮转的51 名实习生进行了模块网格化模型训练,实习生普遍反映该模型有很好的学习效果,让他们了解了肾内科临床重点,并能和理论学习的知识点有机融合在一起,开阔了实习生的诊疗视野,也便于对其他科知识点的学习。结论 基于知识点模块网格化,构建模型在肾内科实习生中有很好的带教作用,学生接受肾内科知识点的记忆增强,并能进一步推广到内科其他内容的实习带教中。 相似文献
58.
To investigate the feasibility of arterial spin labeling (ASL) blood flow (BF) and its histogram analysis to distinguish early-stage nasopharyngeal carcinoma (NPC) from nasopharyngeal lymphoid hyperplasia (NPLH).Sixty-three stage T1 NPC patients and benign NPLH patients underwent ASL on a 3.0-T magnetic resonance imaging system. BF histogram parameters were derived automatically, including the mean, median, maximum, minimum, kurtosis, skewness, and variance. Absolute values were obtained for skewness and kurtosis (absolute value of skewness [AVS] and absolute value of kurtosis [AVK], respectively). The Mann–Whitney U test, receiver operating characteristic curve, and multiple logistic regression models were used for statistical analysis.The mean, maximum, and variance of ASL BF values were significantly higher in early-stage NPC than in NPLH (all P < 0.0001), while the median and AVK values of early-stage NPC were also significantly higher than those of NPLH (all P < 0.001). No significant difference was found between the minimum and AVS values in early-stage NPC compared with NPLH (P = 0.125 and P = 0.084, respectively). The area under the curve (AUC) of the maximum was significantly higher than those of the mean and median (P < 0.05). The AUC of variance was significantly higher than those of the other parameters (all P < 0.05). Multivariate analysis showed that variance was the only independent predictor of outcome (P < 0.05).ASL BF and its histogram analysis could distinguish early-stage NPC from NPLH, and the variance value was a unique independent predictor. 相似文献
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