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131.
目的:观察小鼠胃肠运动昼夜节律及药物对节律的影响。方法:小鼠不同时间点灌胃给予蒸馏水及实验药物,同步测定胃排空及小肠推进运动情况。结果:小鼠胃排空及小肠推进运动存在昼夜节律;普瑞博思促进胃肠运动存在时间效应,但对节律无明显影响;阿托品抑制胃肠运动可使原有昼夜节律消失。结论:小鼠胃肠运动功能存在昼夜节律,药物对胃肠运动功能的作用存在时间效应,可使节律发生不同变化。  相似文献   
132.
神经干细胞静脉移植治疗脊髓损伤的实验研究   总被引:3,自引:0,他引:3  
[目的]观察神经干细胞静脉移植对损伤大鼠脊髓功能的治疗作用。[方法]取孕14—16dSD胎鼠的脑室下区组织,体外培养后鉴定细胞。制作脊髓全切模型,伤后1周将Brdu标记好的神经干细胞通过尾静脉注射移植到大鼠体内,移植后及8周行皮层体感诱发电位(CSEP)检测和BBB功能评分,并留损伤脊髓处作病理切片及免疫组化染色。[结果](1)移植后8周BBB评分损伤组、移植组都有所恢复,但都未达到正常水平,移植组恢复较好;(2)模型制作后,CSEP波均消失,细胞移植后8周移植组的波形有不同程度的恢复,但潜伏期延长;(3)移植组大鼠脊髓损伤处存在大量Brdu染色阳性细胞,表明移植的细胞在体内可到达损伤脊髓处并能存活;脊髓损伤部位NF-200及GFAP染色阳性的细胞表明移植的细胞可以分化为具有神经元和胶质细胞特性的细胞。[结论]静脉移植的神经干细胞能到达损伤区代替受损的神经元及神经胶质细胞,使损伤的脊髓功能得到一定程度的恢复。  相似文献   
133.
Atrial fibrillation (AF) may be associated with activation of atrial natriuretic peptide (ANP). The exact trigger for the release of ANP is still being debated. Atrial volume, pressure, and wall stretch are considered to be the main determinants of ANP activation. The aim of the study was to evaluate plasma ANP concentrations in patients with persistent AF and to analyze the echocardiographic determinants of ANP concentration in this group. The study population included 67 patients, 59 ± 7 years of age, with a median AF duration of 5.5 months (range 0.1–12). The relationship between plasma ANP concentrations and echocardiographic left atrial (LA) diameter and volume, and left ventricular (LV) diameter and ejection fraction (EF) was analyzed by logistic regression analysis. The median baseline plasma ANP concentration was 63 pg/mL (range 21–126) in the study group versus 34 pg/mL (range 16–73) in a control group. The mean left antero-posterior atrial dimension, LA volume, LV enddiastolic diameter, and LVEF were 48 mm, 104 mL, 52 mm, and 54%, respectively. A significant linear positive correlation was found between plasma ANP concentration and maximal LA volume (r = 0.62, P < 0.01). A negative correlation was found between LVEF and plasma ANP concentration (r =−0.42, P = 0.01). However, by multivariate regression analysis, no echocardiographic parameter was an independent predictor of plasma ANP concentration. Plasma ANP concentrations were independent of echocardiographic measurements of LA size or LV size and function in patients with persistent AF.  相似文献   
134.
目的:探讨运用DSA设备作吞咽功能检查的价值。材料和方法:用DSA设备对正常组24例,咽异感症患者32例,做上至颅底、下达第七颈椎平面的正侧位动态采集,了解吞咽状况,并行咽传输时间测定,进行对照研究。结果:正常对照组咽传输时间为1.441±0.302s,咽异感症患者咽传输时间为1.367±0.409s,两组结果相比统计学上无显著差异,但后者较易发生咽部钡剂滞留等改变。结论:DSA机由于采集速度快,不但在心血管检查及介入治疗方面有重要意义,而且在非血管性脏器的动力学检查中也起着一定的作用。由于能完整记录钡剂通过咽部的全过程,故此方法是吞咽功能检查的良好方法之一。  相似文献   
135.
A novel balanced SSFP technique for the separation or suppression of different resonance frequencies (e.g., fat suppression) is presented. The method is based on applying two alternating and different repetition times, TR(1) and TR(2). This RF scheme manipulates the sensitivity of balanced SSFP to off-resonance effects by a modification of the frequency response profile. Starting from a general approach, an optimally broadened stopband within the frequency response function is designed. This is achieved with a TR(2) being one third of TR(1) and an RF-pulse phase increment of 90 degrees . With this approach TR(2) is too short ( approximately 1 ms) to switch imaging gradients and is only used to change the frequency sensitivity. Without a significant change of the spectral position of the stopband, TR(1) can be varied over a range of values ( approximately 2.5-4.5 ms) while TR(2) and phase cycling is kept constant. On-resonance spins show a magnetization behavior similar to balanced SSFP, but with maximal magnetization at flip angles about 10 degrees lower than in balanced SSFP. The total scan time is increased by about 30% compared to conventional balanced SSFP. The new technique was applied on phantoms and volunteers to produce rapid, fat suppressed images.  相似文献   
136.
Sodium MRI of the human kidney at 3 Tesla.   总被引:6,自引:0,他引:6  
The sodium concentration gradient in the kidney (from the cortex to the medulla) serves to regulate fluid homeostasis and is tightly coupled to renal function. It was previously shown that renal function and pathophysiology can be characterized in rat kidneys by measuring the sodium gradient with (23)Na MRI. This study demonstrates for the first time the ability of (23)Na MRI to map the distribution of sodium in the human kidney and to quantify the corticomedullary sodium gradient. The study was performed on a 3T Signa LX scanner (GE) using an in-house-built quadrature surface coil. (23)Na images of volunteers were acquired using a 3D coronal gradient-echo sequence at a spatial resolution of 0.3 x 0.3 x 1.5 cm(3) in a 25-min scan time. The signal intensity (relative to the noise) increased linearly from the cortex to each of the medullae with a mean slope of 1.6 +/- 0.2 in relative arbitrary units per mm (Rel.u./mm, N = 6) and then decreased, as expected, toward the renal pelvis. Water deprivation (12 hr) induced a significant increase of 25% (P < 0.05) in this gradient. Based on these results, we suggest that sodium MRI can serve as a valuable noninvasive method for functional imaging of the human kidney.  相似文献   
137.
Objectives –  To assess long‐term functioning and disability after traumatic brain injury (TBI). Material and methods –  Individuals (n = 88) in Norrbotten, northern Sweden, who had been transferred for neurosurgical care were assessed with internationally established TBI outcome measures 6–15 years post‐injury. Results –  There was an improvement in overall outcome from discharge from inpatient rehabilitation to follow‐up. Many individuals had a high degree of motor and cognitive functioning, which enabled them to live independently in their own home without assistance, but there remained a disability related to community reintegration and social participation. This affected their productivity and to some degree their marital stability. The remaining disability and reduced productivity were related to the age at injury and the injury severity. Conclusions –  Our data showed that individuals with a TBI can achieve and maintain a high degree of functioning many years after the injury. Increasing age and a greater injury severity contributed to their long‐term disability.  相似文献   
138.
231例毛细支气管炎,危重型38例占16.4%,抢救成功31例占81.6%。本文讨论了危重型毛细支气管炎并多器官功能衰竭的发生与预后及平喘药物的合理选用。认为早期应用免疫疗法、迅速平喘、保护重要器官功能及合理治疗并存症是抢救成功的关键。  相似文献   
139.
俞劼 《药学教育》2006,22(3):25-27
针对当前激励作用在大学生日常教育活动中的异化和弱化趋势,围绕其在大学生日常教育活动中的应用,阐述了强化和提升激励作用的途径和方式.结合实际,从激励目标的确立、激励方式的选择、激励过程的实施三个层次进行论证.提出构建多层次、多维度的激励目标体系,促进学生的全面发展.  相似文献   
140.
目的观察颈内动脉输注脐血单核细胞(Human cord blood mononuclear cells,HCMNCs)对血管性痴呆(Vascular dementia,VD)大鼠认知功能及脑组织脑源性神经营养因子(Brain-derivedneurotrophicfactor,BDNF)含量的影响。方法改良Pulsinellis四血管阻断法建立VD大鼠模型;体外分离HCMNCs,术后24h颈内动脉输注数量为3×106/0.5ml的BrdU标记细胞;利用穿梭箱系统和ELISA法检测注射HCMNCs后2、4、8周VD大鼠学习记忆能力以及脑组织BDNF含量的变化。结果模型组大鼠主动回避反应比率明显低于对照组(P<0.01),治疗组较模型组显著提高(P<0.01)。术后2周模型组大鼠脑组织BDNF含量较对照组明显增高(P<0.01),4周时达到高峰(P<0.01),8周时则明显下降,与2周时相比有显著性差异(P<0.05);颈内动脉输注HCMNCs后治疗组大鼠脑组织BDNF含量较模型组显著升高(P<0.01),4周时最高(P<0.01),8周时略有下降,但仍维持在较高水平,与4周时相比无显著性差异(P>0.05)。结论颈内动脉输注HCMNCs可显著改善VD大鼠学习记忆能力,增加VD大鼠脑组织BDNF含量,具有脑保护作用。  相似文献   
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