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91.
激光汽化活体生物组织的传热过程分析 总被引:3,自引:0,他引:3
目的:研究激光汽化生物活体组织的传热过程及其影响因素,方法:基于血液灌注率温度依赖型Pennes生物传热方程,建立激光与生物活体组织热相互作用的一般模型,研究组织表面发生汽化相变,中间组织出现热凝结,内层组织发生温升的过程,由此探讨组织中的激光传输特性,以及血液灌注率和边界冷却等因素的影响情况。结果:通过数值计算,得出活体组织表面汽化速度及内部温度分布,研究表明,活体组织对不同激光的吸收能力,血液灌注率与边界冷却放松择组织汽化速度,组织凝结过程及温度分布有显著影响。结论:该模型可用于预测激光汽化蚀除组织的过程,分析结果对激光临床应用具有理论指导意义。 相似文献
92.
目的:探讨精氨酸加压素受体(AVPR1A、AVPR1B)和催产素受体(OXTR)基因多态性在青少年男性暴力攻击行为发生中的作用,并进一步分析基因与基因的交互作用。方法:采用SNa Pshot基因分型技术对138名暴力攻击行为男性少教人员(暴力组)、98名非暴力男性少教人员(非暴力组)以及153名正常成年男性(正常组)的AVPR1A(rs1042615)、AVPR1B(rs28632197)、OXTR(rs13316193、rs2254298、rs53576、rs2268498、rs237885)进行基因分型检测,分析3组间的等位基因和基因型频率。采用多因子降维法(MDR)构建影响暴力攻击行为发生的基因-基因间交互作用模型。结果:暴力组AVPR1B基因rs28632197位点A等位基因频率明显高于非暴力组和正常组(P均0.017),OR值分别为2.24及2.63,95%CI分别为(1.45~3.47)和(1.78~3.88);暴力组与非暴力组及正常组在基因型分布差异有统计学意义(P0.05),暴力组含A等位基因的基因型(AA/AG)明显高于非暴力组和正常组(P0.017);其余位点组间差异无统计学意义。AVPR1B(rs28632197)与OXTR(rs53576)在暴力攻击行为的发生中存在基因间交互作用。结论:AVPR1B基因多态性可能与暴力攻击行为相关;AVPR1B与OXTR基因的交互作用可能增加暴力攻击行为的发生风险。 相似文献
93.
Martin Stacho Sara Letzner Carsten Theiss Martina Manns Onur Güntürkün 《The Journal of comparative neurology》2016,524(14):2886-2913
Previous studies have demonstrated that the optic tecta of the left and right brain halves reciprocally inhibit each other in birds. In mammals, the superior colliculus receives inhibitory γ‐aminobutyric acid (GABA)ergic input from the basal ganglia via both the ipsilateral and the contralateral substantia nigra pars reticulata (SNr). This contralateral SNr projection is important in intertectal inhibition. Because the basal ganglia are evolutionarily conserved, the tectal projections of the SNr may show a similar pattern in birds. Therefore, the SNr could be a relay station in an indirect tecto–tectal pathway constituting the neuronal substrate for the tecto–tectal inhibition. To test this hypothesis, we performed bilateral anterograde and retrograde tectal tracing combined with GABA immunohistochemistry in pigeons. Suprisingly, the SNr has only ipsilateral projections to the optic tectum, and these are non‐GABAergic. Inhibitory GABAergic input to the contralateral optic tectum arises instead from a nearby tegmental region that receives input from the ipsilateral optic tectum. Thus, a disynaptic pathway exists that possibly constitutes the anatomical substrate for the inhibitory tecto–tectal interaction. This pathway likely plays an important role in attentional switches between the laterally placed eyes of birds. J. Comp. Neurol. 524:2886–2913, 2016. © 2016 Wiley Periodicals, Inc. 相似文献
94.
目的 分析体感交互技术训练对帕金森病患者平衡功能、足底压力及跌倒发生率的影响。方法 选取2020年2月-2022年4月三二〇一医院收治的115例帕金森患者,按不同训练方案分为常规组(n=56)与体感交互组(n=59)。常规药物治疗期间,常规组实施传统平衡训练,体感交互组接受体感交互技术训练。比较两组训练4周后Berg平衡量表(Berg Balance Scale,BBS)评分,动、静态足底压力分布,跌倒发生率。结果 训练后体感交互组BBS评分高于常规组(P<0.05);训练前后比较,常规组BBS评分无统计学意义(P>0.05),体感交互组BBS评分有所提升,具有统计学意义(P<0.05)。训练前两组静态、动态足底压力分布无统计学意义(P>0.05),两组静态站立时双脚压力由低到高排序为:2区<1区<3区<6区<5区<4区<7区<8区;行走时左足:2区<6区<1区<3区<5区<4区<7区<8区,右足:2区<6区<1区<3区<5区<7区<8区<4区。训练后两组站立时双足的3区压力上升,双足压力:2区<1区<6区<5区<3区<4区<7区<8区;行走时左足:2区<6区<1区<5区<3区<4区<7区<8区,右足压力分区未变。训练后两组静态跌倒风险指数评分上升,动态跌倒风险指数评分下降,且体感交互组评分优于常规组(P<0.05)。1个月随访期间,常规组发生11例跌倒,体感交互组发生2例,体感交互组跌倒发生率3.39%低于常规组19.64%(P<0.05)。结论 体感交互技术训练能有效改善帕金森患者平衡功能康复情况,有助于更好调整动、静态足底压力分布,降低跌倒风险,减少跌倒发生情况。 相似文献
95.
Bach T Muschter R Sroka R Gravas S Skolarikos A Herrmann TR Bayer T Knoll T Abbou CC Janetschek G Bachmann A Rassweiler JJ 《European urology》2012,61(2):317-325
Context
Laser treatment of benign prostatic obstruction (BPO) has become more prevalent in recent years. Although multiple surgical approaches exist, there is confusion about laser-tissue interaction, especially in terms of physical aspects and with respect to the optimal treatment modality.Objective
To compare available laser systems with respect to physical fundamentals and to discuss the similarities and differences among introduced laser devices.Evidence acquisition
The paper is based on the second expert meeting on the laser treatment of BPO organised by the European Association of Urology Section of Uro-Technology. A systematic literature search was also carried out to cover the topic of laser treatment of BPO extensively.Evidence synthesis
The principles of generation of laser radiation, laser fibre construction, the types of energy emission, and laser-tissue interaction are discussed in detail for the laser systems used in the treatment of BPO. The most relevant laser systems are compared and their physical properties discussed in depth.Conclusions
Laser treatment of BPO is gaining widespread acceptance. Detailed knowledge of the physical principles allows the surgeon to discriminate between available laser systems and their possible pitfalls to guarantee high safety levels for the patient. 相似文献96.
Tomoko Sonoda Junichi Takada Kousuke Iba Sumiyo Asakura Toshihiko Yamashita Mitsuru Mori 《Journal of orthopaedic research》2012,30(10):1529-1534
We hypothesized that environmental factors might affect the relationship between genetic predisposition and the risk of bone mineral density (BMD) loss. Cases were 114 Japanese women with a confirmed diagnosis of postmenopausal osteoporosis and controls were 171 general Japanese women. Genetic risk of SNPs in the estrogen receptors was analyzed by a case–control study. The interaction between gene and environmental factors for osteoporosis were assessed by a case‐only design. Significant increases in osteoporosis risk were observed with minor alleles of rs2077647 located in the first exon and rs2234693 located in the first intron of estrogen receptor α (ESRα). Haplotype CC at these risk SNPs was strongly associated with osteoporosis risk (odds ratio [OR] = 3.15, 95% confidence interval [CI] = 1.83–5.41). There was a statistically significant interaction between haplotype CC and alcohol drinking; moderate alcohol consumption decreased genetic risk of osteoporosis (OR = 0.22, 95%CI = 0.05–0.83). © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 30:1529–1534, 2012 相似文献
97.
98.
背景 细菌脂多糖(lipopolysaccharide,LPS)可激活细胞合成和释放多种细胞因子,导致全身炎症反应.LPS识别及跨膜信号转导是引起细胞效应的关键,成为近年的研究热点.目的 对新近提出的“LPS受体簇”理论和大电导Ca2+激活K+通道(MaxiK)在LPS信号识别中的作用研究进展进行综述.内容 LPS与CD14结合后,不同的信号分子在脂质筏内聚集,LPS被释放到脂质双分子层,并与由多种受体分子组成的受体簇相互作用.根据不同的细胞类型和细菌刺激,形成了不同的LPS受体簇.MaxiK通道在LPS诱导的巨噬细胞信号转导过程的早期即被激活.并且以IκB-α/NF-κB为中心的促炎症反应依赖MaxiK的功能.趋向 需要进一步研究来阐明LPS受体簇在细胞膜特定区域内形成的确切分子机制,以及组成受体簇的几种蛋白分子在刺激识别和信号转导过程中的作用. 相似文献
99.
Oberbeck R Schmitz D Wilsenack K Schüler M Biskup C Schedlowski M Nast-Kolb D Exton MS 《The Journal of surgical research》2003,113(2):248-256
BACKGROUND: The immunomodulatory properties of the pituitary hormone prolactin have been demonstrated. It was proposed that prolactin is important in maintaining normal immune response in several pathological states. We investigated the effect of prolactin administration on the survival and cellular immune functions during systemic inflammation. MATERIALS AND METHODS: Male NMRI mice were subjected to laparotomy (LAP) or sepsis induced by cecal ligation and puncture (CLP). Mice were treated with either saline (LAP/saline; CLP/saline) or prolactin (LAP/PRL, CLP/RPL; 4 mg/kg s.c.). Survival of septic mice was determined 24 and 48 h after CLP. Forty-eight hours after the septic challenge, the proliferative capacity, cytokine release (IL-2, IL-6, IFN-gamma) and apoptosis of splenocytes were determined. Additionally, monitoring of circulating leukocyte distribution was performed (WBC; CD3+, CD4+, CD8+, B220+, NK1.1+, F4/80+ cells by FASCan). RESULTS: CLP was accompanied by a mortality of 47% and induced a decrease in splenocyte proliferation and apoptosis rate. Administration of prolactin significantly increased the mortality of septic mice (81%). This was paralleled by a further decrease of splenocyte proliferation and an increased splenocyte apoptosis. In addition, administration of prolactin augmented the sepsis-induced inhibition of IL-2 release, attenuated the sepsis-induced inhibition of IFN-gamma release, and did not affect the release of IL-6. However, prolactin did not affect the sepsis-induced changes of circulating leukocyte subpopulations. CONCLUSIONS: We conclude that prolactin has profound immunomodulatory properties and that administration of prolactin in pharmacological doses is associated with a decreased survival and an inhibition of cellular immune functions in septic mice. 相似文献
100.
The Eph family of receptor tyrosine kinases and their membrane-bound ligands, the ephrins, play a central role in pattern formation during embryonic development and there is growing evidence that they are also instrumental in the control of tissue dynamics in the adult. The mammary gland is a paradigm for morphogenic processes occurring in the adult, since the gland develops predominantly postnatally and is subjected to continuous cyclic remodeling according to functional demands. Thus, pattern formation and the establishment of a functional organ structure are permanent themes in the mammary gland life cycle. In this paper we summarize the experimental evidence and discuss possible mechanisms by which Ephs and ephrins are modulating mammary epithelial cell adhesion, communication, and migration. Furthermore, we speculate on the different aspects of their influence on normal mammary gland development, function, and carcinogenesis. 相似文献