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161.
Jane S. Paulsen David P. Salmon Andreas U. Monsch Nelson Butters Michael R. Swenson Mark W. Bondi 《Journal of clinical psychology》1995,51(1):48-58
This study compared the discriminative utility of problem-solving and memory tasks in patients with Alzheimer's and Huntington's disease and in age-, education-, and gender-matched normal control subjects. Problem-solving was assessed with a modified version of the Wisconsin Card Sorting Test. Memory was measured with a 10–item, 6-trial version of the Buschke Selective Reminding Test. Receiver Operating Characteristic curves were plotted to determine which measure provided the highest sensitivity (i.e., hit rate) and specificity (i.e., correct rejection rate). Both tests provided excellent detection of dementia (88 to 98% classification accuracy), but were less robust in differentiating between dementia groups. Findings underscore the suitability of both measures to detect mild dementia, but emphasize the importance of specific memory measures to differentiate between cortical and subcortical dementia. 相似文献
162.
Anke de Haan Markus A. Landolt Eiko I. Fried Kristian Kleinke Eva Alisic Richard Bryant Karen Salmon Sue-Huei Chen Shu-Tsen Liu Tim Dalgleish Anna McKinnon Alice Alberici Jade Claxton Julia Diehle Ramón Lindauer Carlijn de Roos Sarah L. Halligan Rachel Hiller Christian H. Kristensen Beatriz O.M. Lobo Nicole M. Volkmann Meghan Marsac Lamia Barakat Nancy Kassam-Adams Reginald D.V. Nixon Susan Hogan Raija-Leena Punamäki Esa Palosaari Elizabeth Schilpzand Rowena Conroy Patrick Smith William Yule Richard Meiser-Stedman 《Journal of child psychology and psychiatry, and allied disciplines》2020,61(1):77-87
163.
164.
The nigrostriatal dopaminergic system assessed in vivo by positron emission tomography in healthy volunteer subjects and patients with Parkinson's disease 总被引:12,自引:0,他引:12
K L Leenders E P Salmon P Tyrrell D Perani D J Brooks H Sager T Jones C D Marsden R S Frackowiak 《Archives of neurology》1990,47(12):1290-1298
A group of healthy control subjects and patients with Parkinson's disease were investigated using positron emission tomography and two tracers as indicators of different specific properties of the presynaptic dopaminergic system in caudate nucleus and putamen. The first tracer, 6-L-(18F)-fluorodopa, was used as an analog of levodopa to assess its regional brain uptake, conversion into, and retention as dopamine and further metabolites. The second tracer, (11C)-nomifensine was employed as an indicator of striatal monaminergic reuptake sites that are principally dopaminergic. We have used this tracer to assess dopaminergic nerve terminal density. In patients with Parkinson's disease, striatal uptake of both tracers was decreased, putamen being significantly more affected than caudate. Side-to-side differences of uptake in putamen, but not caudate, correlated with corresponding left-right differences of scored clinical motor performance. Both 6-L(18F)-fluorodopa and (11C)-nomifensine tracer uptake in putamen was decreased on average to 40% of normal values, suggesting that a substantial part of the cellular elements of the dopaminergic nigrostriatal system is still intact in living parkinsonian patients. This is in contrast to the generally extreme depletion of endogenous dopamine in the putamen of patients found at postmortem. Our results lend support to the search for drug treatments that protect against further nigrostriatal cell loss and that could be exhibited as soon as the disease manifests clinically. If successful, a sufficient striatal nerve terminal pool would remain so that the effectiveness of levodopa as a dopamine repletor could persist. 相似文献
165.
H M Heshmati G Turpin K Nahoul A Carayon D Salmon A Gueguen J L de Gennes 《Acta endocrinologica》1985,108(4):565-569
In order to evaluate the effect of hyperprolactinaemia on gonadal function in men, testicular stimulation by human chorionic gonadotrophin (hCG) (5000 IU/day, 3 consecutive days) was performed on 6 men with chronic hyperprolactinaemia and 6 control subjects. The following parameters were measured before and during the 4 consecutive days following the injections of hCG: the concentration in plasma of testosterone (T), oestradiol-17 beta (E2), dihydrotestosterone (DHT) and the urinary excretion of testosterone glucuronide (TG) and 5 alpha-androstane-3 alpha, 17 beta-diol glucuronide (3 alpha-Diol G). The rises in T, E2, DHT and the ratios of T/DHT and TG/3 alpha-Diol G were similar in both groups, but the rises in TG and 3 alpha-Diol G were lower in the hyperprolactinaemic group after hCG. There was no correlation between the response of T and the increment of E2 in either group. It is suggested that in men with chronic hyperprolactinaemia: 1) there is diminished testicular response to hCG; this could be due to chronic gonadotrophin deficiency or to a direct effect of hyperprolactinaemia on the testes, 2) there is no modulation of T synthesis through inhibition of aromatase activity and E2 secretion and 3) the 5 alpha-reduction of T is not deficient. 相似文献
166.
The ability to clone primary tumors in soft agar has proven useful in the study of the kinetics and biological properties of tumor stem cells. We report the development of an in vitro assay which permits formation of colonies of human monoclonal plasma cells in soft agar. Colony growth has been observed from bone marrow aspirates from 75% of the 70 patients with multiple myeloma or related monoclonal disorders studied. Growth was induced with either 0.02 ml of human type O erythrocytes or 0.25 ml of medium conditioned by the adherent spleen cells of mineral oil-primed BALB/c mice. 5-500 colonies appeared after 2-3 wk in culture yielding a plating efficiency of 0.001-0.1%. The number of myeloma colonies was proportional to the number of cells plated between concentrations of 10(5)-10(6) and back-extrapolated through zero, suggesting that colonies were clones derived from single myeloma stem cells. Morphological, histochemical, and functional criteria showed the colonies to consist of immature plasmablasts and mature plasma cells. 60-80% of cells picked from colonies contained intracytoplasmic monoclonal immunoglobulin. Colony growth was most easily achieved from the bone marrow cells of untreated patients or those in relapse. Only 50% of bone marrow samples from patients in remission were successfully cultured. Tritiated thymidine suicide studies provided evidence that for most myeloma patients, a very high proportion of myeloma colony-forming cells was actively in transit through the cell cycle. Velocity sedimentation at 1 g showed myeloma stem cells sedimented in a broad band with a peak at 13 mm/h. Antibody to granulocyte colony-stimulating factor did not reduce the number or size of the colonies. Increased numbers of myeloma colonies were seen when the marrow was depleted of colony-stimulating factor elaborating adherent cells before plating. This bioassay should prove useful in studying the in vitro biological behavior of certain bone marrow-derived (B)-cell neoplasia. In addition, systematic and predictive studies of anticancer drug effects on myeloma stem cells should now be feasible. 相似文献
167.
四种中成药对气血双虚模型小鼠血象及免疫水平的影响 总被引:1,自引:0,他引:1
目的:为艾滋病抗病毒疗法所致的骨髓不良反应筛选疗效确切的中成药,观察分析参芪颗粒、复方阿胶浆、贞芪扶正颗粒、复方皂矾丸四种中成药对放血和注射环磷酰胺联合复制的气血双虚模型小鼠血象及免疫水平的影响。方法:实验于2005-08/09在河南中医学院药理实验室完成。①参芪颗粒(江西山高制药有限公司生产,批号040702);复方阿胶浆(山东东阿阿胶股份有限公司生产,批号050446);贞芪扶正颗粒(甘肃扶正药业科技股份有限公司生产,批号040803);复方皂矾丸(陕西郝其军制药有限责任公司生产,批号041014);当归补血口服液(郑州市协和制药厂生产,批号041122);环磷酰胺(上海华联制药有限公司生产,批号050101)。②选取清洁级昆明种小鼠150只,随机数字表法分为15组,10只/组:1~3组分别灌服参芪颗粒混悬液3,2,1g/kg;4~6组分别灌服复方阿胶浆30,20,10mL/kg;7~9组分别灌服贞芪扶正颗粒混悬液15,10,5g/kg;10~12组分别灌服复方皂矾丸混悬液2.4,1.6,0.8g/kg;第13组灌服当归补血口服液10g/kg;剩余2组为空白对照组和模型对照组,分别给于同体积生理盐水10g/kg。各组给药1次/d,连续给药10d。③除空白对照组外,其他各组从给药第1天开始建立气血双虚模型。每只鼠尾部放血0.25mL/10g,然后分别于第2,4,6,8天腹腔注射环磷酰胺80,40,40,40mg/kg。空白对照组同时间点仅腹腔注射等体积生理盐水。末次注射环磷酰胺后2h,眼眶取血,一部分用于血象测定,另一部分离心取血清,测定血细胞比容及血清中巨噬细胞集落刺激因子水平;解剖取胸腺和脾脏,检测胸腺皮质厚度、胸腺淋巴细胞数、脾小结大小、脾脏淋巴细胞数病理学指标的变化。结果:150只小鼠全部进入结果分析,放血和注射环磷酰胺并用可成功建立小鼠气血双虚模型。①与模型对照组比较,参芪颗粒3g/kg组、贞芪扶正颗粒10,5g/kg组、复方皂矾丸1.6g/kg组均可升高气血双虚模型小鼠白细胞水平(t=2.18~2.74,P<0.05),贞芪扶正颗粒15g/kg组作用更为显著(t=2.98,P<0.01);参芪颗粒1g/kg组、复方阿胶浆20mL/kg组、贞芪扶正颗粒15,10g/kg组均可升高红细胞水平(t=2.44~2.69,P<0.05),复方阿胶浆30mL/kg组、贞芪扶正颗粒5g/kg组、复方皂矾丸2.4,1.6g/kg组作用更为显著(t=2.91~3.66,P<0.01);当归补血口服液组、复方阿胶浆20mL/kg组、参芪颗粒3,1g/kg组、贞芪扶正颗粒15,10,5g/kg组均可升高血红蛋白水平(t=2.27~2.85,P<0.05),复方阿胶浆30mL/kg组、复方皂矾丸2.4,1.6g/kg组作用更为显著(t=3.07~4.04,P<0.01);当归补血口服液组、参芪颗粒3,2g/kg组均可升高血小板水平(t=2.20~2.41,P<0.05)。②与模型对照组比较,参芪颗粒2g/kg组、贞芪扶正颗粒5g/kg组均可升高气血双虚模型小鼠血细胞比容(t=2.01~2.62,P<0.05),参芪颗粒1g/kg组、复方阿胶浆30,20,10mL/kg组、贞芪扶正颗粒15,10,5g/kg组、复方皂矾丸2.4,1.6,0.8g/kg组作用更为显著(t=3.18~4.36,P<0.01);参芪颗粒2g/kg组、复方阿胶浆30,20,10mL/kg组、贞芪扶正颗粒15,10,5g/kg组、复方皂矾丸2.4,1.6g/kg组均可显著升高巨噬细胞集落刺激因子水平(t=3.60~6.80,P<0.01)。③与模型对照组比较,当归补血口服液组、参芪颗粒3,2,1g/kg组、复方阿胶浆30,20,10mL/kg组、贞芪扶正颗粒15,10,5g/kg组、复方皂矾丸2.4,1.6,0.8g/kg组均可显著增加气血双虚模型小鼠胸腺皮质厚度(t=3.71~9.34,P<0.01),增大脾小结(t=3.36~11.97,P<0.01),增加脾脏淋巴细胞数(t=4.29~10.44,P<0.01);复方阿胶浆30mL/kg组可明显增加小鼠胸腺淋巴细胞数(t=2.45,P<0.05),当归补血口服液组、参芪颗粒3,2,1g/kg组、复方阿胶浆20,10mL/kg组、贞芪扶正颗粒15,10,5g/kg组、复方皂矾丸2.4g/kg组作用更为显著(t=3.22~8.20,P<0.01)。结论:①四种中成药对气血双虚模型小鼠血红蛋白升高作用相近,以复方阿胶浆和贞芪扶正颗粒对白细胞和红细胞水平升高作用为强,以复方阿胶浆和贞芪扶正颗粒对血小板水平升高作用为优。②四种中成药对气血双虚模型小鼠血细胞比容的影响无差异,以贞芪扶正颗粒和复方皂矾丸对巨噬细胞集落刺激因子水平的升高作用为优。③以参芪颗粒、复方阿胶浆、贞芪扶正颗粒对胸腺皮质厚度和淋巴细胞数的促进作用为优,以参芪颗粒、贞芪扶正颗粒、复方皂矾丸对脾小结和脾脏淋巴细胞数的促进作用为优。 相似文献
168.
169.
目的:利用免疫磁性细胞分选系统分离纯化骨髓衍生肝干细胞亚群c-Kit lin-。方法:实验于2006-07/08在南方医科大学实验动物中心完成。6~8周龄的SPF级纯系BALB/C雄性小鼠10只,体质量18~20g。收集小鼠股骨骨髓细胞,利用免疫磁性细胞分选系统,通过两步法分选纯化c-Kit lin-:将获取的lin-细胞悬液8℃条件下1500r/min离心10min,弃上清,按80μL/107加入Buffer重悬细胞。按20μL/107加生物素抗体磁珠,混匀,4℃冰箱孵育15min,按1mL/107加入Buffer洗细胞1次,8℃条件下1500r/min离心10min,弃上清,按500μL/108加入Buffer重悬细胞。Buffer500μL润MS柱,悬液过柱后,Buffer500μL/次洗柱3次,柱子脱离磁场,加1mLBuffer,用配套柱塞推出柱中的c-Kit lin-细胞,收集到c-kit lin-细胞,细胞计数。取2.0×106个细胞分成10等份,流式细胞仪分析c-Kit lin-细胞纯度,计算回收率,评估纯化效率,苔盼兰染色检测纯化前后的细胞活力。计算活细胞的百分率。细胞纯度和细胞回收率的计算:细胞纯度=分离产物中的阳性细胞数/分离细胞的总细胞数×100%,细胞回收率=分离产物中的阳性细胞数/起始标本阳性细胞总数×100%。结果:10只小鼠均进入结果分析。利用免疫磁性细胞分选系统分选出的骨髓衍生肝干细胞亚群c-Kit lin-细胞纯度和回收率分别为(77.98±2.34)%,75.40%,纯化前后细胞活力不受影响。结论:免疫磁性细胞分选系统能有效分选骨髓衍生肝干细胞亚群c-Kit lin-,纯度和回收率高,且不影响细胞活力。 相似文献
170.
目的:观察白藜芦醇对一次性力竭游泳大鼠肝脏组织的作用及发挥作用的最佳口服剂量。方法:实验于2006-05/07在成都体育学院运动医学系动物实验室完成。①实验分组:选取雄性SD大鼠70只,随机分为7组,每组10只,分别为安静对照组,运动对照组,运动 15mg/kg白藜芦醇组,运动 50mg/kg白藜芦醇组,运动 100mg/kg白藜芦醇组,运动 200mg/kg白藜芦醇组,运动 300mg/kg白藜芦醇组。②实验干预:不同剂量白藜芦醇组每天灌胃15,50,100,200,300mg/kg白藜芦醇,安静对照组和运动对照组分别灌胃相同体积的溶媒(二甲亚砜 生理盐水),连续5周。末次给予实验用样品1h后,各运动组每只鼠尾跟部负荷3%体质量铅皮,置于水深50cm、水温(31±1)℃游泳槽中游泳。游泳力竭后即刻,股动脉取血并迅速取出肝组织。③指标检测:赖氏比色法测定血清中谷丙转氨酶活性;邻苯三酚自氧化法测定肝组织超氧化物歧化酶活性;硫代巴比妥酸法测定肝组织丙二醛含量。结果:纳入动物70只,均进入结果分析。①血清谷丙转氨酶活性和肝组织中丙二醛含量:运动对照组显著高于安静对照组,不同剂量白藜芦醇组低于运动对照组(P<0.05或P<0.01)。运动 100,200,300mg/kg白藜芦醇组低于运动 15,50mg/kg白藜芦醇组[谷丙转氨酶活性:(972.36±121.86),(944.36±105.35),(888.34±88.68),(1773.52±89.35),(1377.78±27.01)nkat/L,P<0.01;丙二醛含量:(7.90±2.56),(7.69±3.69),(7.13±2.62),(19.90±2.21),(12.16±1.78)μmol/g,P<0.05]。100,200,300mg/kg白藜芦醇组间差异无显著性。②肝脏组织中超氧化物歧化酶活性:运动对照组显著低于安静对照组,不同剂量白藜芦醇组高于运动对照组(P<0.05或P<0.01)。运动 100,200,300mg/kg白藜芦醇组高于15,50mg/kg白藜芦醇组[(2325.80±163.37),(2379.14±121.86),(2447.16±89.18),(1096.05±120.19),(1514.64±28.17)μkat/g,P<0.01]。结论:①白藜芦醇对力竭性运动大鼠肝脏组织具有保护作用。②100,200,300mg/kg白藜芦醇对肝脏组织发挥保护作用效果优于15,50mg/kg,建议使用100mg/kg白藜芦醇就能达到理想效果。 相似文献