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1.
目的建立一种狼疮样肾炎动物模型,为人类狼疮性肾炎(LN)实验和临床研究提供基础。方法取雌性亲代DBA/2的淋巴细胞分4次经静脉注射雌性子代F1代杂交鼠(C57BL6× DBA2)。注射时间为0,3,7,10 d。每次注射淋巴细胞数为50× 106。结果尿白蛋白于第4次注射后2周开始升高,第12周达高峰;血抗ds-DNA水平于第4次注射后2周已明显升高,至第4周达高峰,各时点与对照组差异明显。普通光镜(PAS、PASM)示肾小球基底膜增厚,系膜轻度增生,小管间质炎症细胞浸润;免疫荧光示IgG沿基底膜呈线状或颗粒状沉积,部分小管基底膜亦可见其沉积;电镜显示膜性肾炎改变,基底膜增宽,内有电子致密物沉积,上皮细胞足交融合。结论本实验所建立狼疮样肾炎动物模型,主要为膜性肾炎。  相似文献   

2.
采用复杂性分析中的样品熵算法,计算并分析了受试者在单任务事件以及双任务事件活动过程中的神经电生理数据.在利用样品熵算法对短时程(秒)脑电数据的复杂度和规则度进行计算之前,首先应用了代替数据分析法,以排除所分析的实验数据是由线性加随机部分构成.所有的实验数据分别在单任务和双任务等不同的生理条件下采集.其中单任务为一个听觉辨别任务;双任务有两种形式,分别为听觉任务和不同的震动任务的结合.计算结果显示,任何一种双任务过程中脑电信号的熵值都明显的低于单任务状态时脑电信号的熵值(P<0.05~0.001).研究表明对应于受试者仅仅进行单任务工作而言,当受试者处于双任务工作状态时大脑的神经信息传递可能会受到某种程度的削弱,神经信息流通的范围也可能更为孤立.结果进一步说明对于短时程(秒)脑电信号分析,样品熵算法是有效的非线性分析方法.  相似文献   

3.
大鼠心脏血压超负荷诱导左心室HSP70基因表达   总被引:15,自引:1,他引:14  
黄生宁  杨鸿 《生理学报》1994,46(4):333-337
本工作应用热休克蛋白70(HSP70)核酸分子杂交方法,测定了大鼠腹主动脉缩窄后左心室HSP70mRNA的水平。结果表明:大鼠腹主动脉缩窄后4h,动脉血压已明显升高,并持续在高水平上;大鼠左心室重/体重比在第三天开始增加,然后持续升高,第4周时比对照组增加59%;左心室HSP70mRNA在腹主动脉缩窄后4h已明显升高,1d,2d,1w均维持在高水平,1w后逐渐消失。实验结果提示:大鼠心肌负荷增加早期,左心室HSP70mRNA表达明显增加。  相似文献   

4.
微型生态系统中正磷酸直的周转时间的估算   总被引:3,自引:1,他引:2  
在考查罗非鱼或鲢、鳙下行影响的微型生态系统实验后期,以水柱正磷酸盐(PO4-P)完全被浮游植物摄取所需要的时间为指标,估算了系统中PO4-P的周转时间,其中浮游折PO4-P摄取率是采用挂瓶法来测定和估算的。结果表明,两组实验中大多数有鱼系统的浮游植物PO4-P摄取率都显地比无鱼系统高,而PO4-P周转时间的估算值均显地小于无鱼系统,经相关分析测定,两组实验中浮游植物的PO4-P摄取率皆显地正  相似文献   

5.
张涛  杨卓 《生物物理学报》2005,21(2):157-165
首先应用混沌计算方法:关联维数D2和最大李亚普努夫指数LLE,以及替代数据分析法,分析了男性受试者在平静状态下记录的呼吸系统时间序列的混沌特征。同时,在呼吸变量的非线性分析中首次引进了被称为C0复杂度的新技术.它的应用将有助于更好地理解自主神经系统中潜在的生理过程。LLE计算的替代数据法分析结果显示,没有明确的证据可以证实受试者在平静状态下的呼吸时序的模态是混沌的。然而,C0复杂度的计算结果却表明大部分呼吸系统的时间序列表现为某种程度的复杂性,这为呼吸模态的非随机变化的属性提供了部分的实验和计算证据。更进一步,C0复杂度有可能以一种新的、确定的方式给出呼吸系统在激励状态下的量化改变。  相似文献   

6.
RAPD在双歧杆菌菌种鉴定及分型研究中的应用   总被引:3,自引:0,他引:3  
采用近年来兴起的一种新的分子生物学分型技术RAPD即AP-PCR对20株4种不不双歧杆菌进行了基因指纹图谱的构建,其结果不同双歧杆菌种间存在同源性和多态性。本研究结果表明RAPD技术可用于双歧杆菌菌种鉴定及分型。  相似文献   

7.
选取20名年轻的(21-29岁)和20名年老的(70—80岁)血压正常的健康受试者为研究对象,以12位、250Hz采集每位受试者的指端脉搏波数据、为了研究脉搏波波形特征与生理因素的关系,提出了脉搏波导数最大值这一新的特征参数,该参数具有灵敏度高、计算简单的优点.我们用MATLAB编程自动检测出波形特征点的位置,并计算出每位受试者的各项特征参数值、结果如下:脉搏波导数最大值是年轻组明显大于年老组(P〈0.01),波图面积的K值是年轻组小于年老组(P〈0.1).结果预示了这些指标可作为评价心血管系统功能的重要依据。  相似文献   

8.
小鼠每天腹腔注射4-氨公-2’,4’-二氯二苯醚(2’,4’-dicl)及4-氨基-4’-甲基二苯醚(4’-CH3)4天,于末次给药24h后实验,发现:(1)以小鼠戊巴比妥睡眠时间作为体内P450活性指标,4’-CH3组P450活性高于生理盐水组,而2’,4’-diCl组小鼠体内P450活性低于生理盐水组。(2)两处理组小鼠体外测得肝微粒体P450含量均显著高于生理盐水组(P<0.05),低于苯巴比妥组。(3)2’,4’-diCl组小鼠由zoxazolamine引起的瘫痪时间显著高于生理盐水组(P<0.01),提示该化合物对体内P448活性亦有抑制作用。体外实验也发现,两者对BNF诱导的大鼠肝微粒体P448的活性均有不同程度的抑制。  相似文献   

9.
李松涛  钟少斌 《遗传学报》1995,22(2):103-108
RAPD是一种新发展的分子标记技术,本实验利用这种技术对小麦抗白粉病基因Pm4a的近等基因系进行分析。在100个随机引物中找到了3个引物在这对抗白粉病的近等基因系中所扩增出的带型出现差异。并根据理论计算所找到的差异与抗生基因Pm4a连锁的概率是0.7,即3个差异中应有2个标记与抗性基因连锁。  相似文献   

10.
本工作调查了常氧和三种减压低氧环境中,中度吸气阻力(IR,0.44kPa·s·L ̄(-1)负荷对最大有氧工作能力(VO_(2max))的影响。受试者为6名健康的男性青年。结果表明:无IR负荷及IR负荷条件下,VO_(2max)和耐力时间(ET)均显示出随低氧程度的增加而显著降低(P<0.01);与常氧环境的结果相似,在低氧环境中IR负荷导致了VO_(2max)的进一步减小(P<0.01)。上述结果提示,无论常氧和低氧环境,中度的IR负荷均可导致人员极限工作能力的下降。  相似文献   

11.
目的:探索中国汉族人群Toll样受体4基因Asp299Gly多态性与阿尔茨海默病(AD)相关性。方法:样本来源于2010.01-2012.01上海普陀区人民医院门诊及病房、瑞金医院、华山医院痴呆专病门诊就诊的200例AD患者(年龄在45-85岁之间)与同时期入组的患者配偶或体检中心200例健康对照(统计分析时有10例患者因故剔除),所有入组者为无血缘关系的中国汉族人。AD诊断由神经科专科医生参照美国国立神经病学、语言交流障碍和卒中老年性痴呆和相关疾病学会工作小组(NINCDS-ADRDA)关于AD的诊断标准确定。所有入组者抽取随机静脉血2 ml,血样标本使用双脱氧链终止法进行TLR4基因Asp299Gly突变检测。实验前期随机抽取部分血样进行TLR4蛋白定量测定。因为使用双脱氧链终止法未检测到TLR4基因Asp299Gly突变型,在实验后期我们又使用连接酶检测反应法对其中352例样本进行TLR4基因Asp299Gly突变复测及ApoE等位基因型检测。结果:与对照组相比,AD组外周血TLR4蛋白含量增高,其差异性具有统计学意义(P<0.05)。基因检测结果显示TLR4基因Asp299Gly突变两组均为野生型A,AD组ApoEε4基因型频率(包含纯合子及杂合子)高达35.90%,明显高于对照组(17.35%)。结论:AD组外周血TLR4蛋白表达量增高提示TLR4与AD发病有一定相关性,但没有证据表明TLR4基因Asp299Gly突变与AD发病有相关性。  相似文献   

12.
动脉粥样硬化病人LDL受体基因启动子序列的高甲基化改变   总被引:1,自引:0,他引:1  
探讨动脉粥样硬化(Atherosclerosis,AS)病人LDLR基因启动子区12个CpG二核苷酸结构甲基化的改变。改进并联合应用巢式、Touchdown—PCR,甲基化敏感单链构象分析法(methylationsensitive—single—stand conformation analysis,MS—SSCA),对61例AS病人及28例健康对照者的LDLR基因启动子区CpG岛的甲基化状态进行检测。在AS患者中发现三种不同的甲基化模式,即完全甲基化、部分甲基化和非甲基化。61例AS患者中有2例完全甲基化,13例部分甲基化,其余为非甲基化.甲基化率为24.59%;28例正常对照者中仅1例发生部分甲基化,甲基化率为3.57%。两组甲基化率差异有显著性(P〈0.05)。AS病人LDLR基因启动子区甲基化程度增高,在LDLR基因调控区的高甲基化修饰可能参与了AS的发病。同时,改进并联合应用的巢式PCR、Touchdown—PCR.MS—SSCA法降低了对DNA模板严格度的要求,提高了灵敏度和特异性,在检测基因甲基化中具有方便、经济、效率高的优点,有良好的应用前景。  相似文献   

13.
Consumer test subjects were split into four groups: (1) Rewarded — told they would receive payment; (2) Unrewarded — told they would not receive payment; (3) Hungry — told not to eat before the test; and (4) Pre-fed — told to eat a meal before the test. Hedonic responses for four breaded fish samples were collected. The test design was then repeated using microwave popcorn as stimuli. Rewarded subjects and hungry subjects rated samples higher than did either the unrewarded subjects or the pre-fed subjects. The responses of both the rewarded and the hungry subjects indicated no hedonic differences between samples; but among the unrewarded and the pre-fed subjects, significant differences between samples were found. Results present a dilemma for those experimenters using acceptance ratings by consumers to guide product development. This paper discusses the issue of whether these, and other unresolved factors, need to be controlled when conducting consumer tests.  相似文献   

14.
A batch-contact alumina-extraction method has been used to separate [18F]-L-6-fluorodopa (FD) from its principal metabolite, 3-O-methyl-[18F]-6-fluorodopa (3-OMe-FD), in arterial blood plasma samples collected from subjects pretreated with carbidopa during positron emission tomography (PET) scans. The time course of the metabolite-corrected blood plasma activity is then used as an input function for kinetic analysis of striatal FD uptake. Results obtained from using the batch-contact alumina-extraction method were compared with those from high performance liquid chromatography, and also with those from a chromatographic alumina cartridge technique developed in this laboratory. In 60 human subjects including normal healthy volunteers and patients diagnosed as having a movement disorder, arterial blood plasma samples were collected after FD injection during a two-hour PET scan and analyzed by the batch-contact alumina-extraction method. The activity ratio (metabolites/FD) increased linearly with time for all subjects. However, there was a wide variation in the slope of the plot of the activity ratio (metabolites/FD) versus time among the subjects. No significant linear or curved relationship was observed between the slope and the age of the subject. Separation of FD from its metabolites is therefore necessary for each PET-FD study conducted.  相似文献   

15.
Typically, diagnosis of enteric fever due to Salmonella spp. is by bacterial isolation from blood culture; however, the blood culture method is slow, not always available, and not informative in patients with antibiotic treatment. Salmonella spp. uses the hilA gene (component of the pathogenicity island I) to invade epithelial cells and produce infection. Using the hilA gene sequence a PCR test was designed to detect Salmonella in blood samples. The sensitivity (S), specificity (SP), positive predictive value (PPV) and negative predictive value (NPV) of the PCR method were obtained by testing the blood samples from 34 patients with suspected of enteric fever. Presence of S. typhi was confirmed by blood culture. Blood samples were also tested from 35 patients with infections due to other non-Salmonella pathogens, again corroborated by blood culture (Klebsiella pneumoniae, 9; Serratia marcescens, 5; Escherichia coli, 4; Pseudomonas aeruginosa, 9; Providencia alcalifaciens, 4; Enterobacter cloacae, 4). Control samples were obtained from 150 healthy volunteers. The S, SP, PPV and NPV for the PCR method were all 100%. The lowest number of colony forming units/ml detected by PCR in blood samples was 10.  相似文献   

16.
Normal and malignant melanocytes produce melanins and melanin-related metabolites, most of which are retained in the cells but some are secreted into the blood and then excreted in the urine. In this study, we developed a method to measure levels of eumelanin in urine samples and evaluated its clinical significance in comparison with the melanin-related metabolites 6-hydroxy-5-methoxyindole-2-carboxylic acid (6H5MI2C) and 5-S-cysteinyldopa (5-S-CD), and with pheomelanin, measured after degradation as 4-amino-3-hydroxyphenylalanine (4-AHP). The method is based on the production of pyrrole-2,3,5-tricarboxylic acid (PTCA) on permanganate oxidation of eumelanin, followed by quantification by liquid chromatography. For 118 urine samples from 10 control subjects, mean urinary excretions of PTCA, 6H5MI2C, 5-S-CD and 4-AHP were 19, 67, 37 and 59 micromol/mol creatinine respectively. In melanoma patients (n = 45), the mean urinary excretions of PTCA, 6H5MI2C, 5-S-CD, and 4-AHP were 91, 926, 4070 and 3530 micromol/mol creatinine respectively. Median level of PTCA in melanoma patients was elevated 2.1-fold compared with control subjects. The degrees of elevation for 6H5MI2C, 5-S-CD, and 4-AHP were 1.8-, 22- and 6.2-fold respectively. Thus, although urinary PTCA is of little clinical value in following the progression of melanoma, urinary 4-AHP appears to be of considerable value in this respect.  相似文献   

17.
In this study we have analyzed the effects of variations in the concentrations of oxygen and of blood sugar on light sensitivity; i.e. dark adaptation. The experiments were carried out in an air-conditioned light-proof chamber where the concentrations of oxygen could be changed by dilution with nitrogen or by inhaling oxygen from a cylinder. The blood sugar was lowered by the injection of insulin and raised by the ingestion of glucose. The dark adaptation curves were plotted from data secured with an apparatus built according to specifications outlined by Hecht and Shlaer. During each experiment, observations were first made in normal air with the subject under basal conditions followed by one, and in most instances two, periods under the desired experimental conditions involving either anoxia or hyper- or hypoglycemia or variations in both the oxygen tension and blood sugar at the same time. 1. Dark adaptation curves were plotted (threshold against time) in normal air and compared with those obtained while inhaling lowered concentrations of oxygen. A decrease in sensitivity was observed with lowered oxygen tensions. Both the rod and cone portions of the curves were influenced in a similar way. These effects were counteracted by inhaling oxygen, the final rod thresholds returning to about the level of the normal base line in air or even below it within 2 to 3 minutes. The impairment was greatest for those with a poorer tolerance for low O2. Both the inter- and intra-individual variability in thresholds increased significantly at the highest altitude. 2. In a second series of tests control curves were obtained in normal air. Then while each subject remained dark adapted, the concentrations of oxygen were gradually decreased. The regeneration of visual purple was apparently complete during the 40 minutes of dark adaptation, yet in each case the thresholds continued to rise in direct proportion to the degree of anoxia. The inhalation of oxygen from a cylinder quickly counteracted the effects for the thresholds returned to the original control level within 2 to 3 minutes. 3. In experiments where the blood sugar was raised by the ingestion of glucose in normal air, no significant changes in the thresholds were observed except when the blood sugar was rapidly falling toward the end of the glucose tolerance tests. However, when glucose was ingested at the end of an experiment in low oxygen, while the subject remained dark adapted, the effects of the anoxia were largely counteracted within 6 to 8 minutes. 4. The influence of low blood sugar on light sensitivity was then studied by injecting insulin. The thresholds were raised as soon as the effects of the insulin produced a fall in the blood sugar. When the subjects inhaled oxygen the thresholds were lowered. Then when the oxygen was withdrawn so that the subject was breathing normal air, the thresholds rose again within 1 to 2 minutes. Finally, if the blood sugar was raised by ingesting glucose, the average threshold fell to the original control level or even below it. 5. The combined effects of low oxygen and low blood sugar on light sensitivity were studied in one subject (W. F.). These effects appeared to be greater than when a similar degree of anoxia or hypoglycemia was brought about separately. 6. In a series of experiments on ten subjects the dark adaptation curves were obtained both in the basal state and after a normal breakfast. In nine of the ten subjects, the food increased the sensitivity of the subjects to light. 7. The experiments reported above lend support to the hypothesis that both anoxia and hypoglycemia produce their effects on light sensitivity in essentially the same way; namely, by slowing the oxidative processes. Consequently the effects of anoxia may be ameliorated by giving glucose and the effects of hypoglycemia by inhaling oxygen. In our opinion, the changes may be attributed directly to the effects on the nervous tissue of the visual mechanism and the brain rather than on the photochemical processes of the retina.  相似文献   

18.
Vasoactive intestinal polypeptide (VIP) is now considered to be a prolactin-releasing factor (PRF). The aim of this study was to determine the VIP concentration in peripheral blood in patients with prolactin-secreting adenoma compared to healthy subjects. We also examined the effect of bromocriptine administration on the plasma VIP concentration in patients with prolactinoma. Nine patients with prolactinoma (6 women and 3 men, aged 27-50) and 7 healthy control subjects (4 women and 3 men, aged 26-40) were examined. Blood samples for prolactin and VIP were collected at 06:00, 12:00, 18:00, 24:00. In prolactinoma blood was taken before and after bromocriptine administration. Serum prolactin concentration was determined by the radioimmunoassay. VIP concentration was measured by a specific radioimmunoassay Kit-INCSTAR Corp. (Minnesota, USA). Statistical significance was calculated using the analysis of variance. A single 5 mg oral dose of bromocriptine decreased the mean prolactin concentration during the first 24 hours of treatment. Plasma VIP concentration was higher in prolactinoma patients compared to healthy subjects. There was no change in plasma VIP level after bromocriptine administration. In conclusion: in patients with prolactin secreting adenoma the plasma VIP concentration is increased.  相似文献   

19.
Patients with chronic obstructive pulmonary disease (COPD) who are defined as frequent exacerbators suffer with 2 or more exacerbations every year. The molecular mechanisms responsible for this phenotype are poorly understood. We investigated gene expression profile patterns associated with frequent exacerbations in sputum and blood cells in a well-characterised cohort. Samples from subjects from the ECLIPSE COPD cohort were used; sputum and blood samples from 138 subjects were used for microarray gene expression analysis, while blood samples from 438 subjects were used for polymerase chain reaction (PCR) testing. Using microarray, 150 genes were differentially expressed in blood (>±1.5 fold change, p≤0.01) between frequent compared to non-exacerbators. In sputum cells, only 6 genes were differentially expressed. The differentially regulated genes in blood included downregulation of those involved in lymphocyte signalling and upregulation of pro-apoptotic signalling genes. Multivariate analysis of the microarray data followed by confirmatory PCR analysis identified 3 genes that predicted frequent exacerbations; B3GNT, LAF4 and ARHGEF10. The sensitivity and specificity of these 3 genes to predict the frequent exacerbator phenotype was 88% and 33% respectively. There are alterations in systemic immune function associated with frequent exacerbations; down-regulation of lymphocyte function and a shift towards pro-apoptosis mechanisms are apparent in patients with frequent exacerbations.  相似文献   

20.
Oral administration of carnitine in normal and diabetic subjects showed a marked decrease in the level of blood glucose during the oral glucose tolerance test (OGTT) except for the three hour samples in diabetic subjects, while a decrease in the level of subsequent blood pyruvate samples was observed during the OGTT in normal and diabetic subjects after the administration of carnitine. During the OGTT, the peak of blood glucose and blood pyruvate level was generally delayed in the diabetic subjects. Furthermore, the mean blood pyruvate levels were elevated above those of normal subjects during the late stages of the test. The mean levels of blood glucose and blood pyruvate of all samples after the administration of carnitine were significantly higher in diabetics than the corresponding values in noramls. Carnitine administration decreased the total blood amino acid nitrogen level only in diabetic subjects. Carnitine caused a highly significant increase in the activity of serum alanine aminotransferase in normal and diabetic subjects, while it had no effect on the activity of serum aspartate aminotransferase. In goats, the level of blood glucose during the intravenous glucose tolerance test (IVGTT) was not affected by carnitine (1,3 or 6 mg/kg body weight). Carnitine in all doses used had no effect on the total blood amino acid nitrogen during the IVGTT, or on the activity of serum alanine aminotransferase and serum aspartate aminotransferase in the fasting samples. Acetyl-D,L-beta-methylcholine had no effect on the level of blood glucose, total blood amino acid nitrogen, the activity of serum alanine aminotransferase or serum aspartate aminotransferase in normal and diabetic subjects. The level of blood pyruvate decreased both in normal and diabetic subjects, in the samples that represented the peak of the curve. Glycine betaine had no effect on blood glucose, pyruvate, total blood amino acid nitrogen and the activity of serum alanine aminotransferase or serum aspartate amino transferase in normal and diabetic subjects or in goats.  相似文献   

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