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51.
The long-held belief that degeneration of the cholinergic basal forebrain was central to Alzheimer's disease (AD) pathogenesis and occurred early in the disease process has been questioned recently. In this regard, changes in some cholinergic basal forebrain (CBF) markers (e.g. the high affinity trkA receptor) but not others (e.g., cortical choline acetyltransferase [ChAT] activity, the number of ChAT and vesicular acetylcholine transporter-immunoreactive neurons) suggest specific phenotypic changes, but not frank neuronal degeneration, early in the disease process. The present study examined the expression of the low affinity p75 neurotrophin receptor (p75(NTR)), an excellent marker of CBF neurons, in postmortem tissue derived from clinically well-characterized individuals who have been classified as having no cognitive impairment (NCI), mild cognitive impairment (MCI), and mild AD. Relative to NCI individuals, a significant and similar reduction in the number of nucleus basalis p75(NTR)-immunoreactive neurons was seen in individuals with MCI (38%) and mild AD (43%). The number of p75(NTR)-immunoreactive nucleus basalis neurons was significantly correlated with performance on the Mini-Mental State Exam, a Global Cognitive Test score, as well as some individual tests of working memory and attention. These data, together with previous reports, support the concept that phenotypic changes, but not frank neuronal degeneration, occur early in cognitive decline. Although there was no difference in p75(NTR) CBF cell reduction between MCI and AD, it remains to be determined whether these findings lend support to the hypothesis that MCI is a prodromal stage of AD.  相似文献   
52.
目的 了解含 β-神经生长因子 (β- NGF)基因的表达质粒 PSVCEP NGF- CAT在培养肌母细胞中的表达及 L ipofect AMINE阳离子脂质体介导的转染效率。方法 将表达质粒 PSVCEP NGF- CAT经 L ipofectAMINE转染至培养成的肌母细胞中 ,用免疫细胞化学方法检测基因在肌母细胞内的表达。结果 培养肌母细胞在转染 6小时吞噬脂质体最显著 ,转染 48小时后约 40 %的肌母细胞胞质内有β- NGF基因表达。结论 含β- NGF基因的表达质粒 PSVCEP NGF- CAT可以在培养肌母细胞中表达 ,脂质体转染的方法简便、有效  相似文献   
53.
Detection of cell apoptosis by MTT assay.]   总被引:1,自引:0,他引:1  
OBJECTIVE: To study the feasibility of using MTT assay to detect cell apoptosis. METHODS: K562 cells were grown in RPMI 1640 medium supplemented with 10% calf serum and 4 micromol/L arsenic trioxide. Apoptosis was induced in the cultured cells by As2O3, and the cells were detected with optical microscope, DNA gel electrophoresis and MTT staining respectively. RESULT: MTT staining could also accurately detect cell apoptosis, by which the apoptotic cells were easily distinguished from normal cells and dead cells. CONCLUSION: MTT staining is simple, convenient and practical for detecting cell apoptosis.  相似文献   
54.
人胎盘基因表达谱芯片的初步研究   总被引:5,自引:2,他引:3  
目的:制备人胎盘基因表达谱芯片,并用于基因差异表达分析。方法:用基因芯片点样仪将胎盘基因文库探讨打印在氨基包被的玻片上制备表达谱芯片。分别提取对照组与三氧化二砷处理的K562细胞总RNA,纯化mRNA后反转录成cDNA,再以限制性显示技术进行荧光标记,将两组荧光标记的样品混合后与芯片进行杂交,杂交后清洗芯片,干燥后对芯片进行扫描,分析杂交结果。结果:建立了较可靠的制备与检测基因表达谱芯片的方法,并筛选出45个差异表达基因片段,结论:制备的人胎盘基因表达谱芯片可有效地应用于基因的差异表达分析。  相似文献   
55.
目的 :研究tritonWR 13 3 9致小鼠高脂血症时血清二乙基对硝基苯磷酸酯酶 (ParaoxonaseI ,PON 1)活性的变化及PON 1活性与血浆脂质含量之间的关系。方法 :在小鼠尾静脉注射tritonWR13 3 9后的 3h ,6h ,12h ,2 4h ,48h ,72h ,眼球摘除术取血 ,用酶标法测定小鼠血浆总胆固醇 (TC) ,甘油三酯 (TG ) ,高密度脂蛋白 -胆固醇 (HDL -C) ,载脂蛋白AI (ApoAI) ,载脂蛋白B (ApoB含量 ) ,并计算出ApoAI/ApoB ,HDL -C/TC比值 ,用分光光度计法测定PONI活性。结果 :TritonWR 13 3 9尾静脉注射后 3h ,小鼠血浆TC和TG含量即急剧增高 ,与对照组相比 ,P <0 .0 1,分别在注射后 2 4h和 3h达到峰值 ,随后逐渐下降 ,其中血浆TG含量在注射后 48h即恢复正常水平。tritonWR13 3 9尾静脉注射后 3h ,小鼠血浆HDL -C和ApoB含量急剧增高 ,与对照组相比 ,P <0 .0 5,分别在注射后 2 4h和 6h达到峰值 ,随后逐渐下降 ,分别在注射后 48h和 72h恢复正常水平。tritonWR13 3 9尾静脉注射后 3h ,小鼠血浆ApoAI含量即急剧降低 ,与对照组相比 ,P <0 .0 5,随后逐渐增高 ,在注射后 6h即恢复正常水平。tritonWR 13 3 9尾静脉注射后 3h ,小鼠血浆ApoAI/ApoB和HDL-C/TC比值减少 ,与对照组相比 ,P <0 .0 1,随后逐渐增高 ,其中ApoAI/ApoB比值在 72h恢复  相似文献   
56.
BACKGROUND: Gastric cancer (GC) is the leading cause of cancer deaths in China. Our study prospectively evaluated the impact of repeated endoscopic screens on GC mortality in a high-risk population in China. METHODS: Between 1989 and 1999, a population-based gastroscopic screening was conducted in 4,394 residents of Linqu County, China, a region with the highest rates of GC worldwide. Residents ages 35 to 64 years received initial gastroscopies with biopsies in 1989. Repeated endoscopies were performed in 1994 and 1999. Cancer occurrences and deaths were actively monitored throughout the entire period until July 2000. Mortality from GC was compared with expected values based on mortality rates obtained for Linqu in the 1990-1992 Chinese Cancer Mortality Survey. RESULTS: Between March 1989 and July 2000, 39,303 person-years were accumulated; 85 new GCs occurred, 29 (34.5%) were in early stage. Fifty-eight cases (68%) were identified at one of the screens. The number of observed deaths from GC (37) was close to the expected (36.8). The standardized mortality ratio was 1.01 (95% CI 0.72-1.37) for the entire cohort, 1.13 (95% CI 0.77-1.57) for males, and 0.65 (95% CI 0.26-1.32) for females. CONCLUSIONS: Despite high population coverage with repeated screens, no reduction in GC mortality was observed in this high-risk population in China.  相似文献   
57.
Dimethyl isosorbide (DMI), which is currently under investigation for its potential use as a pharmaceutical vehicle and drug permeation enhancer, is a water-miscible liquid with relatively low viscosity. The solubilization behavior of DMI as a cosolvent for nonpolar drugs was characterized via dielectric constant measurements of binary solvent systems containing DMI and either water, propylene glycol (PG), or polyethylene glycol (PEG). Evidence from the dielectric constant profiles and NMR studies suggest that DMI undergoes complexation with water and PG, but not with PEG, through hydrogen bonding interactions. The solvent complexation exhibited a major effect on the solubilities of prednisone, dexamethasone, and prednisolone in the mixed solvent systems. Maximum solubility of each drug was found to occur near a DMI/water or DMI/PG concentration ratio of 1:2. In the DMI–PEG mixed system, while there is no apparent interaction between DMI and PEG molecules, the solubility of prednisone was found to increase with decreasing dielectric constant.  相似文献   
58.
谷氨酰胺肠外营养对创伤后多器官衰竭患者的营养作用   总被引:1,自引:0,他引:1  
目的探讨补充谷氨酰胺(Gln)的肠外营养在严重创伤后多器官衰竭(MOF)患者治疗中的作用。方法采用随机对照方法,将60例MOF患者分为Gln组和对照组,每组30例。Gln组给予Gln1.5ml/kg联合常规治疗[热量104~125kJ/(kg·d),其中脂肪供热40%,氮供给量为0.2~0.25g/(kg·d)的完全胃肠外营养(TPN)支持];对照组仅给予常规治疗,连续7d。对照分析营养指标、免疫指标、并发症及临床结果。结果所有患者营养指标(血清白蛋白、前清蛋白、转铁蛋白)和免疫指标(IgG、IgA、IgM)明显减低,处于负氮平衡。第8天时,Gln组营养指标明显高于治疗前及对照组(P<0.05),负氮平衡得到纠正(P<0.05),而对照组仅血清白蛋白、转铁蛋白较治疗前增高(P<0.05),仍处于负氮平衡(P>0.05)。Gln组免疫指标明显高于治疗前及对照组(P<0.01),而对照组仅IgG高于治疗前(P<0.01)。对照组14例(46.7%)出现了血清胆红素、丙氨酸转氨酶和血糖的升高,而Gln组仅4例(13.3%)增高(P<0.05),至14d时对照组病死率为36.7%,而Gln组仅为10%,两者相比差异有显著性(P<0.05)。结论应用Gln的肠外营养能够明显纠正MOF患者的营养代谢障碍,纠正负氮平衡,增强免疫功能,降低并发症及病死率。  相似文献   
59.
赤芍总苷对沙土鼠全脑缺血再灌注损伤的保护作用   总被引:3,自引:0,他引:3  
OBJECTIVE: To study the protective effects of the total paeony glycoside (TPG) against global cerebral ischemia-reperfusion injury in gerbils. METHODS: Gerbils models of global cerebral ischemia-reperfusion injury were prepared by bilateral common carotid artery ligation for 12 min followed by 24-hour reperfusion. The effects of TGP on brain edema index, superoxide dismatase (SOD) activity and malonaldehyde (MDA) concentration of the cerebral tissue homogenate and pathology of the brain were examined 24 h after model establishment. RESULTS: Compared with the model group, TPG at the doses of 200 and 400 mg/kg could significantly relieve brain edema, enhance SOD activity and lower MDA concentration in the gerbils. Pathological examination showed that the gerbils with TPG treatment had milder injury of the cells in the hippocampal CA1 region. CONCLUSIONS: TPG has obvious protective effects against global cerebral ischemia-reperfusion injury.  相似文献   
60.
Background:  Clusterin is a ubiquitous 80 kDa heterodimeric glycoprotein previously shown to be expressed on tumor cells of systemic and, to a lesser extent, primary cutaneous anaplastic large cell lymphoma (PC-ALCL). Lymphomatoid papulosis (LyP), an important differential diagnosis of ALCL, has been studied for clusterin expression in only a small number of cases. The aim of this study was to compare clusterin immunostaining patterns in LyP and other cutaneous histologic simulants with those of PC-ALCL.
Methods:  Formalin-fixed, paraffin-embedded sections of PC-ALCL (6), LyP (20), mycosis fungoides with large cell transformation (MF-LCT, 12), pityriasis lichenoides et varioliformis acuta (PLEVA, 12), arthropod bite reaction (ABR, 12) and lymphomatoid reactions (LR, 9) were immunostained for clusterin and evaluated for staining pattern and distribution. All diagnoses were made with clinicopathologic correlation.
Results:  Characteristic dot-like Golgi staining was identified in 10/20 LyP (50%), 4/6 PC-ALCL (67%) and 9/12 MF-LCT (75%). Two of 12 PLEVA (17%), 1 of 12 ABR (8%) and 2 of 8 LR (25%) had lymphocytes (< 25%) with diffuse cytoplasmic staining. Dermal dendritic cells stained strongly for clusterin. High background staining occurred in some cases.
Conclusion:  Clusterin immunostaining does not reliably distinguish between LyP, PC-ALCL or MF-LCT, but could distinguish LyP from its reactive histologic simulants.  相似文献   
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