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101.
Robert C. Knowlton MD Nicholas D. Lawn FRACP James M. Mountz MD PhD Ojha Buddhiwardhan MD Suzanne Miller RN BSN Jorge G. Burneo MD Ruben I. Kuzniecky MD 《Journal of neuroimaging》2004,14(4):324-330
PURPOSE: To examine the application of statistical parametric mapping (SPM) to analyze ictal single-photon emission computed tomography (SPECT) scans in surgical candidates with extratemporal lobe epilepsy. METHODS: The authors selected patients who underwent successful ictal SPECT acquisition in the process of surgical treatment of intractable partial epilepsy. Thirteen patients were identified who met inclusion criteria for confident seizure localization from either intracranial electroencephalogram recordings or epilepsy surgery outcome. In these cases, ictal scans were registered to an in-house-developed normal SPECT atlas composed of 14 spatially normalized brains of normal subjects. SPM96 was used to test on a voxel-by-voxel basis for statistically significant increases in blood flow associated with each patient's ictal scan. The results were then mapped back onto the patient's magnetic resonance image (MRI) for final interpretation. Statistical parametric mapping (SPM) analysis of ictal SPECT scans was compared to both conventional visual interpretation and the analysis of subtraction ictal SPECT co-registered to MRI (SISCOM). RESULTS: Ten of 13 patient scans showed localizing focal ictal increases in regional cerebral blood flow, all of which were concordant with ultimate epilepsy localization. Of the 3 cases not localized with SPM, 1 was localized by conventional visual interpretation and another, not localized by visual interpretation, was correctly localized with SISCOM. Two cases not localized by SISCOM were localized by both visual and SPM analysis. CONCLUSIONS: This work provides supportive evidence for proof of principle that SPM can be used to provide objective, accurate analysis of ictal SPECT scans in patients with extratemporal lobe epilepsy. 相似文献
102.
静脉血气分析及其临床应用进展 总被引:2,自引:0,他引:2
动脉血气分析是严重心肺疾病和许多代谢性疾病的重要检测手段,在血流动力学稳定状态下,动、静脉血气的CO2气体含量和酸碱参数非常接近,但在循环功能衰竭等情况下,动、静脉血气出现分离现象,此时可能需同时作静脉血气。静脉血气分析对危重患者特别是循环衰竭的患者可以提供组织氧合和酸碱状态更切实的评价,并可能对有效复苏提供更好的指导。 相似文献
103.
玉郎伞提取物对大鼠自发性高血压的影响 总被引:3,自引:0,他引:3
目的:研究玉郎伞提取物(YLS)对自发性高血压大鼠(SHR)及正常大鼠血压(BP)的影响。方法:应用颈动脉插管测压法,连接MS2000多媒体生物信号记录系统测定静注YLS前及药后20s、30s、lmin、2min、5min时的收缩压(SP)、舒张压(DP)、平均动脉压(MP)。结果:YLS使SHR及正常大鼠血压明显降低(P<0.01),降压作用维持时间较短,给药后5min血压基本恢复正常;YLS对去甲肾上腺素(NA)和异丙肾上腺素(ISO)的作用无明显影响。结论:YLS对正常大鼠及SHR血压有明显的降低作用。 相似文献
104.
服用左炔诺孕酮滴丸和妈富隆1年对血压、血糖和血脂的影响 总被引:1,自引:0,他引:1
杨玉健 《天津医科大学学报》2003,9(3):373-377
目的:观察第二、三代口服避孕药(COC)对育龄妇女体重指数、血压、血糖和血脂的影响。方法:将自愿服用COC避孕1年的妇女105例随机分为两组,其中54例给予第二代COC(EE/LNG组),51例给予第三代COC(EE/DG组)。并对研究前后所有病例的体重指数(BMI)、血压、血糖和血脂代谢指标进行比较分析。结果:EE/LNG组:BMI、收缩压、舒张压、甘油三酯(TG)、总胆固醇(TC)、低密度脂蛋白(LDL)和载脂蛋白B(ApoB)水平均升高,高密度脂蛋白(HDL)水平下降,血糖、载脂蛋白AI(ApoAI)水平无明显改变。EE/DG组收缩压、TG、HDL水平升高,BMI、舒张压、血糖、TC、LDL、ApoAI和ApoB均未发生显著变化。以上所有测量指标均未超出正常范围。结论:使用1年第二、三代COC对妇女BMI、血压和血脂代谢都有微弱的影响,对空腹血糖无明显影响。第三代COC对妇女BMI、收缩压、舒张压、TG、TC、LDL、HDL水平和ApoB的不利影响小于第二代,更加安全可靠。 相似文献
105.
Andrew M Speer Mark W Willis Peter Herscovitch Margaret Daube-Witherspoon Jennifer Repella Shelton Brenda E Benson Robert M Post Eric M Wassermann 《Neuropsychopharmacology》2003,54(8):818-825
BACKGROUND: Repetitive transcranial magnetic stimulation (rTMS) affects the excitability of the motor cortex and is thought to influence activity in other brain areas as well. We combined the administration of varying intensities of 1-Hz rTMS of the motor cortex with simultaneous positron emission tomography (PET) to delineate local and distant effects on brain activity. METHODS: Ten healthy subjects received 1-Hz rTMS to the optimal position over motor cortex (M1) for producing a twitch in the right hand at 80, 90, 100, 110, and 120% of the twitch threshold, while regional cerebral blood flow (rCBF) was measured using H(2)(15)O and PET. Repetitive transcranial magnetic stimulation (rTMS) was delivered in 75-pulse trains at each intensity every 10 min through a figure-eight coil. The regional relationship of stimulation intensity to normalized rCBF was assessed statistically. RESULTS: Intensity-dependent rCBF increases were produced under the M1 stimulation site in ipsilateral primary auditory cortex, contralateral cerebellum, and bilateral putamen, insula, and red nucleus. Intensity-dependent reductions in rCBF occurred in contralateral frontal and parietal cortices and bilateral anterior cingulate gyrus and occipital cortex. CONCLUSIONS: This study demonstrates that 1-Hz rTMS delivered to the primary motor cortex (M1) produces intensity-dependent increases in brain activity locally and has associated effects in distant sites with known connections to M1. 相似文献
106.
本文观察了52侧(男46,女6)成人尸体臀上动、静脉深上支进入髂嵴情况.臀上动、静脉深上支分为前、中、后支;本文测量了臀上动、静脉深上支的外径及各分支进入髂嵴的距离.臀上动、静脉深上支的分支在髂嵴前部及中部分布较多,前支的分支为3~8支,其中以4~6支者为多见,占78.8±5.5%;中支的分支1~4支,其中以2~3者为多见,占73.1±6.1%.因此,臀上动脉深上支作为游离髂骨移植术取髂嵴的前部和中部较宜. 相似文献
107.
Katsuyoshi Hori Maroh Suzuki Shigeru Tanda Sachiko Saito Mika Shinozaki Qiu-Hang Zhang 《Cancer science》1991,82(11):1309-1316
To elucidate the significance of angiotensin II (AID-induced hypertension chemotherapy, changes of tissue blood flow both in normal subcutis and in tumors (AH109A, LY80) were measured with the hydrogen gas clearance method. A newly-developed anesthetic machine was used to keep the animals' condition constant. Tissue blood flow in normal subcutis and tumors always fluctuated with time under normotension. The nature and the rate of fluctuation in tumor Wood flow were almost identical in two different types of tumors. However, the fluctuation of blood flow in tumor and that in normal subcutis were almost always inversely related when blood flows in these different tissues were measured simultaneously, i.e., when tissue blood flow in normal subcutis decreased, tumor blood flow increased, and vice versa. The findings supported the idea that the connection mode between the tumor vascular bed and normal vascular bed is a parallel circuit. Vascular resistance in the normal vascular bed under All-induced hypertension seemed to be greater than that under normotension, because the All-increased tumor blood flow always exceeded the maximum tumor blood flow under normotension. Due to the fluctuations of tumor blood flow, no-flow or low-flow areas, resistant to delivery of anti-cancer drugs, moved sporadically within the tumor under the normotensive condition. However, good conditions for drug delivery to tumor tissue were induced by All-induced hypertension. 相似文献
108.
B. BEGAUD L. DANG TRAN J.L. MONTASTRUC and P. MONTASTRUC 《Fundamental & clinical pharmacology》1987,1(3):153-159
The cardiovascular effects of mesulergine were studied in anesthetized dogs. Intravenous (IV) administration (0.3 mg/kg) significantly decreased blood pressure in neurogenic hypertensive dogs without any change in heart rate. This effect was completely antagonized by IV administration of domperidone (0.5 mg/kg). Intracisternal administration of mesulergine (0.03, 0.3 and 3 mg/kg) did not produce any change in blood pressure. However, with the highest dose we observed a significant rise in heart rate during the first 2 min (which was probably nonspecific). These results suggest that mesulergine lowers blood pressure in sinoaortic-denervated dogs by means of a peripheral mechanism probably involving DA2 receptors. The findings confirm the potential interest of dopamine-receptor agonists as future antihypertensive agents. 相似文献
109.
以23例肾功能不全与20例肾功正常患者的唾液尿素氮、钠、钾、舌面pH值和血液的相应生化检查作对照。结果唾液尿素氮、钾与血尿素氮、钾成正相关性。证实了中医“津血同源”“肾为唾”的理论。 相似文献
110.
C. Frostell M.D. H. Blomqvist C.-J. Wickerts 《Acta anaesthesiologica Scandinavica》1987,31(8):711-716
Twenty-four mongrel dogs were anaesthetized and ventilated mechanically in the supine position. Extravascular lung water (EVLW) and central blood volume (CBV) were measured with a double indicator (dye/cold) dilution technique. Both indicators were detected intravascularly in the aortic root with a fibreoptic thermistor catheter. Seven dogs ventilated with a positive end-expiratory pressure (PEEP) of 1.0 kPa (10 cmH2O) for a short period of time (less than 20 min) displayed no significant change in EVLW as measured with the indicator dilution technique (= EVLWi), while reductions were seen in both CBV (15%, P less than 0.01) and cardiac output (CO-thermodilution technique) (10%, P less than 0.05). Another seven dogs ventilated with a PEEP of 1.0 kPa for 8 h showed a gradual increase in EVLWi. After 8 h, a mean increase of 34% (P less than 0.01) was recorded, and the increase was also verified by post-mortem gravimetric determination of EVLW (= EVLWg), displaying an increase of 61% (P less than 0.01). In five dogs ventilated with zero end-expiratory pressure (ZEEP) for 8 h, no changes in EVLWi, CO, and CBV were observed, and EVLWg was mean 4.39 g/kg body weight (BW). Five additional dogs were sacrificed after 15 min of anaesthesia without catheterization and EVLWg was found to be 4.24 g/kg BW. It is concluded that EVLWi does not change measurably during ZEEP or short periods of PEEP. However, long periods (8 h) of PEEP result in elevated EVLWi values. Gravimetry supports these conclusions.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献