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211.
In order to visualize the global and downstream neuronal responses to deep brain stimulation (DBS) at various targets, we have developed a protocol for using blood oxygen level dependent (BOLD) functional magnetic resonance imaging (fMRI) to image rodents with simultaneous DBS. DBS fMRI presents a number of technical challenges, including accuracy of electrode implantation, MR artifacts created by the electrode, choice of anesthesia and paralytic to minimize any neuronal effects while simultaneously eliminating animal motion, and maintenance of physiological parameters, deviation from which can confound the BOLD signal. Our laboratory has developed a set of procedures that are capable of overcoming most of these possible issues. For electrical stimulation, a homemade tungsten bipolar microelectrode is used, inserted stereotactically at the stimulation site in the anesthetized subject. In preparation for imaging, rodents are fixed on a plastic headpiece and transferred to the magnet bore. For sedation and paralysis during scanning, a cocktail of dexmedetomidine and pancuronium is continuously infused, along with a minimal dose of isoflurane; this preparation minimizes the BOLD ceiling effect of volatile anesthetics. In this example experiment, stimulation of the subthalamic nucleus (STN) produces BOLD responses which are observed primarily in ipsilateral cortical regions, centered in motor cortex. Simultaneous DBS and fMRI allows the unambiguous modulation of neural circuits dependent on stimulation location and stimulation parameters, and permits observation of neuronal modulations free of regional bias. This technique may be used to explore the downstream effects of modulating neural circuitry at nearly any brain region, with implications for both experimental and clinical DBS.  相似文献   
212.
The use of mouse models in experimental research is of enormous importance for the study of hepatic physiology and pathophysiological disturbances. However, due to the small size of the mouse, technical details of the intraoperative monitoring procedure suitable for the mouse were rarely described. Previously we have reported a monitoring procedure to obtain hemodynamic parameters for rats. Now, we adapted the procedure to acquire systemic and hepatic hemodynamic parameters in mice, a species ten-fold smaller than rats. This film demonstrates the instrumentation of the animals as well as the data acquisition process needed to assess systemic and hepatic hemodynamics in mice. Vital parameters, including body temperature, respiratory rate and heart rate were recorded throughout the whole procedure. Systemic hemodynamic parameters consist of carotid artery pressure (CAP) and central venous pressure (CVP). Hepatic perfusion parameters include portal vein pressure (PVP), portal flow rate as well as the flow rate of the common hepatic artery (table 1). Instrumentation and data acquisition to record the normal values was completed within 1.5 h. Systemic and hepatic hemodynamic parameters remained within normal ranges during this procedure.This procedure is challenging but feasible. We have already applied this procedure to assess hepatic hemodynamics in normal mice as well as during 70% partial hepatectomy and in liver lobe clamping experiments. Mean PVP after resection (n= 20), was 11.41±2.94 cmH2O which was significantly higher (P<0.05) than before resection (6.87±2.39 cmH2O). The results of liver lobe clamping experiment indicated that this monitoring procedure is sensitive and suitable for detecting small changes in portal pressure and portal flow rate. In conclusion, this procedure is reliable in the hands of an experienced micro-surgeon but should be limited to experiments where mice are absolutely needed.  相似文献   
213.
华南稻田农田害鼠复合防治指标的理论研究   总被引:1,自引:0,他引:1  
何淼  冯志勇 《生态学报》2003,23(1):211-217
依据对华南地区稻田3种主要害鼠黄毛鼠、板齿鼠和小家鼠的田间捕获率调查,以及对害鼠造成的相应水稻产量损失率(y)研究,建立了水稻产量损失率与鼠密度关系的多元线性回归方程。确定板齿鼠作为本项研究的标准鼠种,利用3种农田鼠害的捕获率在回归方程中对应的系数,计算出农田害鼠的标准当量损害指标。结果显示,每个标准鼠单位造成的水稻产量损失率分别相当于4.084个黄毛鼠当量单位,或31.593个小家鼠当量单位。进一步,对原始调查数据进行二次处理,建立了标准当量(x)与(y)的相互关系数学模型;文中配合EIL计算公式,求出了在不同水稻产量和不同灭鼠效果等条件下的华南农田害鼠的复合防治指标。  相似文献   
214.
Background Muscle recovery following peripheral nerve repair is sup-optimal. Follistatin (FST), a potent muscle stimulant, enhances muscle size and satellite cell counts following reinnervation when administered as recombinant FST DNA via viral vectors. Local administration of recombinant FST protein, if effective, would be more clinically translatable but has yet to be investigated following muscle reinnervation. Objective  The aim of this study is to assess the effect of direct delivery of recombinant FST protein on muscle recovery following muscle reinnervation. Materials and Methods  In total, 72 Sprague-Dawley rats underwent temporary (3 or 6 months) denervation or sham denervation. After reinnervation, rats received FST protein (isoform FS-288) or sham treatment via a subcutaneous osmotic pump delivery system. Outcome measures included muscle force, muscle histomorphology, and FST protein quantification. Results  Follistatin treatment resulted in smaller muscles after 3 months denervation ( p  = 0.019) and reduced force after 3 months sham denervation ( p  < 0.001). Conversely, after 6 months of denervation, FST treatment trended toward increased force output ( p  = 0.066). Follistatin increased satellite cell counts after denervation ( p  < 0.001) but reduced satellite cell counts after sham denervation ( p  = 0.037). Conclusion  Follistatin had mixed effects on muscle weight and force. Direct FST protein delivery enhanced satellite cell counts following reinnervation. The positive effect on the satellite cell population is intriguing and warrants further investigation.  相似文献   
215.
Adipose‐derived stromal cells (ADSC) are increasingly used in clinical applications due to their regenerative capabilities. However, ADSC therapies show variable results. This study analysed the effects of specific factors of ex‐obese patients on ADSC functions. ADSC were harvested from abdominal tissues (N = 20) after massive weight loss. Patients were grouped according to age, sex, current and maximum body mass index (BMI), BMI difference, weight loss method, smoking and infection at the surgical site. ADSC surface markers, viability, migration, transmigration, sprouting, differentiation potential, cytokine secretion, telomere length and mtDNA copy number were analysed. All ADSC expressed CD73, CD90, CD105, while functional properties differed significantly among patients. A high BMI difference due to massive weight loss was negatively correlated with ADSC proliferation, migration and transmigration, while age, sex or weight loss method had a smaller effect. ADSC from female and younger donors and individuals after weight loss by increase of exercise and diet change had a higher activity. Telomere length, mtDNA copy number, differentiation potential and the secretome did not correlate with patient factors or cell function. Therefore, we suggest that factors such as age, sex, increase of exercise and especially weight loss should be considered for patient selection and planning of regenerative therapies.  相似文献   
216.
目的 探究胃肠道手术患者术后感染病原菌及其感染高危因素,为该类患者的治疗提供参考.方法 选择2017年1月至2019年10月于我院行胃肠道手术的106例患者为研究对象,检测感染患者病原菌分布,同时检测感染与非感染患者肠道菌群情况,分析患者术后感染的相关危险因素.结果 106例胃肠道手术患者中感染18例(16.98%),...  相似文献   
217.
袁帅  付和平  武晓东  兴安  甘红军  岳秀贤 《生态学报》2017,37(14):4795-4806
放牧被认为是草地生态系统的主要干扰之一。许多研究表明,放牧影响了啮齿动物的个体条件、繁殖、种群动态、群落组成及群落多样性等多个方面。由于受传统统计学方法的限制,这些研究只是单独的对放牧作用进行假设检验,而没有将多个假设放在同一个框架内进行验证。2006—2011年,采用标志重捕法对内蒙古阿拉善荒漠区不同放牧生境中啮齿动物优势种的数量进行研究并使用结构方程建模的方法将可能影响荒漠啮齿动物优势种的环境因子(气候条件、土壤硬度、植物隐蔽、植物生物量等19个指标)与啮齿动物优势种种群动态结合后进行多假设检验,旨在找出不同放牧干扰下制约优势啮齿动物环境因子的发生途径。结果表明:气候条件对五趾跳鼠和三趾跳鼠有直接不利影响,隐蔽对于两足活动的五趾跳鼠有负效应,而对四足活动的子午沙鼠有正效应。植物生物量对五趾跳鼠有正效应,但对子午沙鼠有负效应。土壤硬度的增加间接的有利于五趾跳鼠,对子午沙鼠有直接的正效应。因此荒漠啮齿动物优势种种群动态是多个过程共同作用的结果,气候条件是驱动啮齿动物种群动态的根本原因,而放牧会因为改变植物隐蔽而影响啮齿动物在群落中的组成。  相似文献   
218.
目的:研究妊娠期卵巢过度刺激综合征合并卵巢蒂扭转行腹腔镜下保留卵巢术的可行性及安全性。方法:对本院2010年1月-2017年12月妇科住院的9例妊娠期卵巢过度刺激综合征合并卵巢蒂扭转患者进行腹腔镜下保留卵巢术,观察其发病时间、卵巢扭转情况、手术时间、术中出血量、术后并发症及妊娠结局等。结果:9例患者术后均无明显并发症发生,术后随访9例患者妊娠结局均良好,其中,8例患者足月产,1例早产。结论:腹腔镜下妊娠期卵巢过度刺激综合征合并卵巢蒂扭转保留卵巢术对患者维持妊娠及生育功能的影响小、术后并发症低,是一种安全、可行性强的手术。  相似文献   
219.
化学灭鼠对长江流域农区鼠类群落结构的影响   总被引:8,自引:2,他引:6  
张美文  王勇  李波  郭聪  陈安国 《生态学报》2003,23(2):320-329
长江流域农业生态系统内,农田的主要害鼠为褐家鼠、黑线姬鼠、黄胸鼠、小家鼠、东方田鼠等,各地的鼠种组成有所不同,优势鼠种也因地而异。农房区的害鼠主要有褐家鼠、小家鼠、黄胸鼠3种,优势鼠种各地亦有区别。但经化学灭鼠后的残留鼠种却有一共同的特点:灭鼠活动对褐家鼠种群的打击最大,灭后褐家鼠种群密度下降幅度最大;相对而言,小型鼠黑线姬鼠(农田区)与小家鼠(农舍区)及栖息在房屋上层的黄胸鼠,常成为灭鼠活动后的主要残留鼠种。化学灭鼠后鼠类群落结构比灭前都要发生较大的变化,这种差别中维持3a左右,但经过3-4a左右的恢复后,灭鼠区的鼠类群落组成与相似环境内自然演变区的已达基本一致。可见,化学灭鼠活动可以在短时间内对害鼠群落结构造成重大的影响,从长期看,害鼠群落的演变有着自身的规律,灭鼠后一定时期,鼠类群落结构将恢复到环境所决定的水平,灭鼠区的长期演替结构仍与相似环境内未灭鼠区的一样。  相似文献   
220.
目的:基于问题的学习(PBL)结合询证医学(EMB)模式在普通外科临床教学中的应用。方法:选择2015年9月到2016年1月在我院学习的普通外科专业学生74例纳入本次研究,根据简单数字随机表法将其划分为观察组(PBL结合EBM教学模式)以及对照组(传统教学模式)各37例,对比两组考试成绩,课程相关指标,以及评优情况。结果:观察组的基础知识得分、主观题考试得分、个案分析得分以及总分均分别明显高于对照组,差异均有统计学意义(均P0.05)。观察组的课前准备时间、课堂发言次数及授课满意度均明显大于对照组,差异均有统计学意义(均P0.05)。观察组药物选择合理、患者状态评估准确以及符合临床实际上的评优率均明显高于对照组,差异有统计学意义(P0.05)。结论:PBL结合EBM模式应用在普通外科的临床教学过程中,效果明显,能较好地激发学生学习兴趣并提高其学习成绩,还可提升学生的评优率,值得给予推广。  相似文献   
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