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排序方式: 共有371条查询结果,搜索用时 10 毫秒
81.
82.
Tohoru Takeda Jin Wu Qingkai Huo Tetsuya Yuasa Kazuyuki Hyodo Takao Akatsuka 《Journal of synchrotron radiation》2008,15(5):528-531
Fluorescent X‐ray computed tomography (FXCT) enables visualization of myocardial fatty acid metabolism by using non‐radio‐iodinated I‐5‐(p‐iodophenyl)‐3‐(R,S)‐methylpentadecanoice acid (BMIPP). In this experiment, age‐dependent myocardial metabolic impairment was successfully imaged and analyzed quantitatively in J2N‐k cardiomyopathic hamster using FXCT. 相似文献
83.
Xueting Yao Chao Xu Yurong Cao Lin Lin Hanxu Wu Chang Wang 《Biomedical chromatography : BMC》2019,33(3)
Radiation‐induced brain injury involves acute, early delayed and late delayed damage based on the time‐course and clinical manifestations. The acute symptoms are mostly transient and reversible, whereas the late delayed radiation‐induced changes are progressive and irreversible. Therefore, evaluation of the organ‐specific early response to ionizing radiation exposure is necessary for improving treatment strategies and minimizing possible damage at an early stage after radiation exposure. In the current study, the gas chromatography–mass spectrometry technique based on metabolomics coupled with metabolic correlation network was applied to investigate the early metabolic characterization of rat brain tissues following irradiation. Our findings showed that the metabolic response to irradiation was not just limited to the variations of individual metabolite levels, but also accompanied by alterations of network correlations among various metabolites. Metabolite clustering indicated that energy metabolism disorder and inflammation response were induced following radiation exposure. The correlation networks revealed that the strong positive correlations of differential metabolites were highly reduced and significant negative linkages were highlighted in irradiated groups even without statistical changes in metabolic levels. Our findings provided new insights into our understanding of the radiation‐induced acute brain injury mechanism and clues as to the therapy target for clinical applications. 相似文献
84.
网球发球的背肌损伤原因及康复 总被引:1,自引:0,他引:1
运用运动解剖学的基本知识和方法,对网球发球背肌损伤的不同征象和原因作了详细的分析,并依据受伤的不同情况,给出了切合实际的治疗措施和康复训练方案。 相似文献
85.
目的 探讨脑外伤患者血浆脂联素水平的变化规律及与脑外伤严重度的相关性。方法 选取86例重型脑外伤患者
和86例健康体检者,分别于入院时、入院后第1、2、3、5、7天和体检时清晨空腹抽取静脉血,ELISA 法测定血浆脂联素水平。结果 脑外伤后血浆脂联素水平6h内升高,24h到达高峰,后逐渐下降,入院时、入院后第1、2、3、5、7天的血浆脂联素水平均明显高于健康对照组(均P<0.01);蛛网膜下腔出血、环池消失、中线移位(>5mm)和瞳孔散大患者各个时间点血浆脂联素水平显著高于其对照组(均P<0.01)。入院时格拉斯哥昏迷评分与各个时间点血浆脂联素水平均呈负相关(均P<0.01)。结论 脑外伤后血浆脂联素水平升高,与脑外伤严重度显著相关。 相似文献
86.
Fan-lin Wu Yong-hao Hu Peng Ji Chen-chen Li Jian He 《Biomedical chromatography : BMC》2022,36(6):e5362
87.
In this paper we investigate the bubble collapse dynamics under shock-induced loading near soft and rigid bio-materials, during shock wave lithotripsy. A novel numerical framework was developed, that employs a Diffuse Interface Method (DIM) accounting for the interaction across fluid–solid-gas interfaces. For the resolution of the extended variety of length scales, due to the dynamic and fine interfacial structures, an Adaptive Mesh Refinement (AMR) framework for unstructured grids was incorporated. This multi-material multi-scale approach aims to reduce the numerical diffusion and preserve sharp interfaces. The presented numerical framework is validated for cases of bubble dynamics, under high and low ambient pressure ratios, shock-induced collapses, and wave transmission problems across a fluid–solid interface, against theoretical and numerical results. Three different configurations of shock-induced collapse applications near a kidney stone and soft tissue have been simulated for different stand-off distances and bubble attachment configurations. The obtained results reveal the detailed collapse dynamics, jet formation, solid deformation, rebound, primary and secondary shock wave emissions, and secondary collapse that govern the near-solid collapse and penetration mechanisms. Significant correlations of the problem configuration to the overall collapse mechanisms were found, stemming from the contact angle/attachment of the bubble and from the properties of solid material. In general, bubbles with their center closer to the kidney stone surface produce more violent collapses. For the soft tissue, the bubble movement prior to the collapse is of great importance as new structures can emerge which can trap the liquid jet into induced crevices. Finally, the tissue penetration is examined for these cases and a novel tension-driven tissue injury mechanism is elucidated, emanating from the complex interaction of the bubble/tissue interaction during the secondary collapse phase of an entrapped bubble in an induced crevice with the liquid jet. 相似文献
88.
89.
目的 应用低氧血症二次脑损伤大鼠模型,探讨低氧血症对轻型颅脑损伤(mTBI)后海马神经元及轴索组织结构的二
次损伤作用。方法 采用随机数字表法将大鼠分为正常对照组(8 只)、单纯mTBI 组(10 只)、单纯低氧血症组(10只)及低氧血症二次脑损伤组(10只)。在自制旋转装置致大鼠mTBI基础上,利用动物呼吸机获得控制性低氧血症,从而构建低氧血症二次脑损伤模型。脑损伤后1 周,应用HE染色、免疫组化β-APP 染色及电镜观察大鼠海马组织结构病理学变化。结果 HE 染色发现单纯低氧血症组大鼠海马神经元结构完整、排列有序、神经组织结构致密、未见明显神经元丢失及神经组织结构疏松等病理变化,单纯mTBI组及低氧血症二次脑损伤组大鼠均出现海马神经元肿胀、胞质淡染、密度降低、排列不规则及神经组织结构疏松等损伤表现,但低氧血症二次脑损伤组较单纯mTBI组明显。免疫组化β-APP 染色及电镜观察到低氧血症二次脑损伤组大鼠海马存在轴索肿胀扭曲变形、髓鞘板层分
离及轴索球形成等轴索损伤表现。结论 低氧血症二次脑损伤可明显加重mTBI后海马神经元及轴索组织结构的损伤,及早预防、发现和治疗低氧血症对改善mTBI患者预后具有积极意义。 相似文献
90.
急性心肌梗塞患者血清硒,锌,铜,钙,镁,铁,锶含量的测定 总被引:4,自引:0,他引:4
分别对29例急性心肌梗塞(AMI)病人和40例健康人进行血清中七种微量、常量元素含量测定,结果表明,AMI患者血清Se、Zn、Ca较正常对照组明显降低;血清Cu显著增高,血清Fe、Mg较对照组低,差异不显著;血清Sr两组无差异。对AMI患者与血清硒及各元素间相互关系进行了探讨,指出调整人体微量、常量元素的不平衡状况,对冠心病和AMI的发生、发展和康复有一定的临床意义。 相似文献