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71.
With the development of interventional therapy, it is necessary for evaluating cerebral vessels to instruct treatment and determine prognosis of patients with ischemic stroke; however, correlation of distribution of infarction focus and clinical symptoms with degrees of cerebrovasoular stricture is still unclear.OBJECTIVE: To evaluate the characteristics of cerebral arterial stricture of patients with ischemic stroke with transcranial Doppler (TCD) and color duplex flow imaging (CDFI) and compare the correlation between distribution of cerebral infarction focus and clinical types with magnetic resonance imaging (MRI).DESIGN: Contrast observation.SETTING: Department of Neurology, the First Hospital of Jilin University.PARTICIPANTS: A total of 159 patients with ischemic stroke were selected from the Department of Neurology, the First Hospital of Jilin University from January to December 2005, including 106 males and 53 females aged from 27 to 88 years. Bases on diagnostic criteria of cerebrovascular disease established by Rao et al, clinical manifestations of all patients were evaluated with CT or nuclear magnetic resonance. All patients provided the confirmed consent.METHODS: The accepted patients received TCD and CDFI examination at 1 week after onset of ischemic stroke. Among them, 112 patients received cerebrovascular imaging examination simultaneously. MRI was used to check cerebral infarction focus and cerebrovascular stricture > 50% was regarded as the accepted vessels. In addition, DWI-T2 TCD (Germany) was used to check middle cerebral artery, and degrees of middle cerebral artery were classified into mild, moderate and severe stricture based on blood velocity (140 cm/s,180 cm/s). Stroke was classified based on characteristics of infarction focus and clinical symptoms showed with MRI and correlation with degrees of cerebrovascular stricture was analyzed simultaneously.MAIN OUTCOME MEASURES: Correlation between the characteristics of ischemic stroke and clinical symptoms checked with TCD and CDFI.RESULTS: A total of 159 patients with ischemic stroke were involved in the final analysis; in addition, 112 oases received cerebrovascular imaging examination simultaneously. ① MRI results of 159 patients with cerebral artery occlusive disease (CAOD): There were 131 patients (82.3%) with cerebral infarction, 40 (25.2%)with transient ischemic attack and 4 (2.5%) with subclavian steal syndrome (SSS). ② Infarction types with MRI examination: There were 33 patients (20.8%) with solitary cerebral infarction and 98 (61.6%) with multiple-cerebral infarction. ③ Results of TCD, CDFI, MRI angiography, CT angiography and digital subtraction angiography (DSA): Among 112 patients, 181 lesion sites (61 .8%) were located in cranium and 112 lesion sites were located out of cranium; especially, lesion site was mostly observed in stem of middle cerebral artery (31.2%) and watershed of basilar artery (7.2%) in cranium and the beginning site of internal carotid artery (21 .4%) out of cranium. ④ Correlation of vascular stricture checking with TCD, MRI and clinical diagnosis: On one hand, MRI and clinical diagnosis demonstrated that 68 patients had a watershed infarction; meanwhile,TCD examination indicated that there were 3 patients with mild vascular stricture, 24 with moderate vascular stricture and 36 with severe vascular stricture. On the other hand, among 68 patients with non-watershed infarction, there were 27 patient with mild vascular stricture, 26 with moderate vascular stricture and 15 with severe vascular stricture. There were significant differences (x2 =26.854, P =0.001 ). Clinical diagnosis indicated that 40 patients had transient ischemic attack and TCD examination demonstrated that there were 8 patient with mild vascular stricture, 12 with moderate vascular stricture and 20 with severe vascular stricture. There were significant differences as compared with 68 patients with watershed infarction (x2 =21.258, P =0.001). ⑤Correlation of vascular stricture checking with CDFI, MRI and clinical diagnosis: On one hand, among patients who were determined as watershed infarction with MRI and clinical diagnosis, CDFI examination indicated that there were 32 patients with mild vascular stricture at neck, 25 with moderate vascular stricture and 6 with severe vascular stricture. On the other hand, among patients with non-watershed infarction, there were 48 patient with mild vascular stricture, 18 with moderate vascular stricture and 2 with severe vascular stricture.There were significant differences (x2 =6.018, P =0.019). Among patients with transient ischemic attack checking with clinical diagnosis, there were 23 patient with mild vascular stricture, 9 with moderate vascular stricture and 8 with severe vascular stricture. There were no significant differences as compared with patients with non-watershed infarction (x2 =0.597, P=0.440).CONCLUSION: ① TCD and CDFI are effective marks to determine cerebral arterial stricture and hemodynamical changes. ② Infarction and transient ischemic attack at watershed are generally clinical phenotypes of CAOD patients and infarction at watershed is correlated with degrees of cerebrovascular stricture.③ TCD, MRI and clinical analysis of stroke types are significant for instructing treatment and evaluate prognosis.  相似文献   
72.
抗人生长激素免疫血清的制备和鉴定   总被引:1,自引:1,他引:0  
Using small dosage of human growth hormone to immunize rabbit or guinea pig, it is able to induce anti-hGH antibody formation with high titre and high affinity that could be applied to hGH RIA. In the present study five rabbits and three guinea pigs were immunized with 125-200 micrograms and 250-285 micrograms per animal of hGH respectively, followed by boosters of 10-20 or 160-250 micrograms of hGH at 2-4 week intervals for 6 or 3 months. Blood was drown 1-2 weeks before each booster for determination of antibody formation. Antibody titre and affinity were successively observed and specificity of antibody was determined for the final bleeding. It was shown that titres of immune sera from guinea pigs were much higher than those of rabbit immune sera, but vice versa for antibody affinity. This might be due to larger immunogen dose used for guinea pigs than for rabbits. Fourteen different peptide hormones were tested in reference to cross-immunoreactivity to anti-hGH antibody. It could be demonstrated that the major cross-reactive hormones are hFSH and hLH, and hTSH also reacts to rabbit anti-hGH immune sera at a lesser degree. These cross reactivities are obviously owing to the molecular homogeneities between hGH and these hormones especially of their alpha-subunits.  相似文献   
73.
现察口腔修复临床电刀龈成形术的效果。方法:对81例口腔修复门诊牙体缺损患者用电刀进行牙龈成形术并定期复诊观察。结果:81例术后牙龈全部达到修复要求而立即修复,其中70例术后牙龈稳定,占总数的86.4%。结论:电刀龈成形术是口腔修复临床上一种可行的治疗手段。  相似文献   
74.
In order to investigate the effect of ligustrazine (Lig)i.p.on peritoneal permeability in peritoneal dialysis and its side effects,creatinine was given intravenously and continuously to maintain the high plasma creatinine level.All the rabbits were divided into three groups:normal control group (goup A),group B treated with 0.12% Lig and group C treated with 0.24% Lig.The peritoneal dialysis of all rabbits lasted 2h.The plasma and dialysate levels of glucose,protein and creatining were observed immediate,30min,60min,90min,120min after dialysis.Creastinine dialysate/plasma ratio (D/P),protein D/P ratio,grucose D/Do at different time points after dialysis and creatinine mass transfer area coefficient (MTAC) at 120min were calculated.The structures of peritoneum were observed under optical microscope and electron microscope after continuously intraperitoneal injection of Lig for 14 days.The results showed that the 90-min and 12-min creatinine D/P ratios in the group C were higher than in the group A.The 120-min creatinine MATC in the group C was higher than in the group A.The rabbits treated with Lig did not show significant structure changes of peritoneum and signs of peritoneal irritation.It was suggested that Lig could increase mass transfer ability of peritoneum without significant side effects.  相似文献   
75.
H Deng  X Ma  R Xu  X Chen  Y Zhao  L Yin  D Han 《中国中药杂志》1992,17(4):233-6, inside backcover
The results indicated that RSM could significantly inhibit the lipid peroxidation of normal livers and cultured hepatocytes of rats, induce liver microsomal cytochrome P450 in normal rats, increase nucleic acids, proteins, urea and cerolloplasmin of damaged cultured hepatocytes of rats, relieve ultrastructural damage of cultured hepatocytes induced by CCl4. The pharmacological actions mentioned above should be considered as important mechanisms of RSM against liver injury.  相似文献   
76.
本文采用高效液相色谱法分析研究了进口药品脑活素注射液中的氨基酸含量及其低分子肽的肽图。试验结果反映了该药品的内在质量,同时提出控制质量的可靠方法.  相似文献   
77.
为探讨金属硫蛋白(MT)对豚鼠乳头肌缺血再灌注损伤所致心律失常的影响,利用标准玻璃微电极技术,采用缺氧及复氧豚鼠乳头肌模型,模拟体内缺血再灌注损伤,观察不同浓度MT对豚鼠乳头肌电生理特性的影响。结果显示低浓度的MT(0.002mmol/L)对正常及缺氧和复氧豚鼠乳头肌的动作电位(AP)有关参数及自律性均无影响;中等浓度的MT(0.02mmol/L)仅使正常乳头肌的AP复极达50%时程(APD50)缩短24%(P<0.05),但使缺氧乳头肌的AP复极达20%时程(APD20)、APD50和AP复极达90%时程(APD90)分别缩短68%、56%和43%(P均<0.01),并使静息电位(RP)、AP幅值(APA)和0相最大上升速率(Vmax)分别增加30%、30%和45%(P均<0.01);高浓度的MT(0.1mmol/L)使正常豚鼠乳头肌的APD20、APD50和APD90分别缩短57%、54%和50%(P均<0.01),并且RP、APA及Vmax分别下降22%(P<0.05)、28%(P<0.01)和29%(P<0.05),而使缺氧豚鼠乳头肌的APD20、APD50和APD90分别延长92%、78%和50%(P均<0.01),对RP、APA及Vmax无明显影响。在复氧期间,0.02mmol/L的MT可使自律性的发生率从77.8%降至55.6%(P<0.05);而0.1mmol/L的MT则使自律性的发生率从77.8%降至22.2%(P  相似文献   
78.
本文介绍了用实验方法研究不同管电压, 钢板厚度与散射线之间的关系.结果表明, 透射比随管电压升高而增加, 并随钢板厚度增加而下降;散射比随散射角的增大而逐渐下降, 至180°时为最低值。此研究为X射线探伤作业的辐射防护提供了依据。  相似文献   
79.
鲍善芬  李寒濂 《营养学报》1994,16(4):401-405
对我院老年病房四季112份全膳食中的15种元素(钾、钠、钙、磷、镁、锌、铜、铁、锰、硒、铝、钴、铬、钼、镍)进行了实测。结果表明:钾的平均日摄入量为1809+38mg,接近RDA值的下限;钠的平均日摄入量为5972±146mg远高于1100~3300mg的供给标准。钙、磷、镁的日摄入量已达到了RDA值的标准。全膳食中锌、铜的含量分别为11.68±0.19mg和1.72±0.10rng,略低于RDA值(15mg及2~3mg)的标准,锰含量为3.41±0.09mg硒为98±2.5μg,都处于安全与适宜摄入范围(2.5~5.0mg和50~200μ9)。钴、铬、钼、镍均为人体必需的微量元素、目前我国尚未建立有关营养供给量标准。该项研究结果可为今后确定其推荐供给量标准提供必要的基础资料.  相似文献   
80.
目的研究重庆市新生儿黄疸儿G6PD三种常见基因突变与其临床表现特点之间的关系。初步估计其基因突变频率并探讨其临床意义和遗传学特征。方法应用突变特异性扩增系统(ARMS)法,检测54例重庆市新生儿黄疸儿的G6PD基因突变类型。结果检出G1388A突变39例(72%),G1376T突变8例(15%),未定型者7例(13%)。未检出G95A。结论本研究首次对重庆市新生儿黄疸儿进行G1388A、G1376T和A95G突变检测。提示G1388A和G1376T为重庆市新生儿黄疸儿G6PD缺乏症基因突变的主要类型。ARMS法是一种简便、快速、经济的检测G6PD已知基因突变的方法。本研究发现这两种突变类型仅见于中国人和华裔人群,具有遗传学及临床意义。  相似文献   
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