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71.
马尔尼菲青霉病不同类型病变中免疫反应观察   总被引:2,自引:0,他引:2  
选用2组病变类型不同的6例马尔尼菲青霉病人病变组织,采用免疫组化PAP法,观察病变组织中l8淋巴细胞、巨噬细胞、IgG、IgM、乙等免疫指标。结果发现马尔尼菲青霉病的病变类型取决于机体的免疫功能状态,人体抗马尔尼菲青霉免疫以细胞免疫为主,组织中T细胞的存在对于杀灭真菌、局限病变具有积极意义;体液免疫特别是特异性抗体的出现除具有促进细胞免疫功能外,可能也是脓肿成因之一。  相似文献   
72.
在综合疗法的基础上加用异搏定3~5天治疗流行性出血热(EHF)发热后期病人41例,在尿蛋白转阴、越期率,特别是越少尿期平明显优于对照组,但对 BUN 水平的影响与对照组无异,异搏定对防治 EHF 急性肾衰具有一定疗效。  相似文献   
73.
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   
74.
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   
75.
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   
76.
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   
77.
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   
78.
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   
79.
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   
80.
目的探讨窒息新生儿出生体重对其血清中高同型半胱氨酸血症及低叶酸水平的关系。方法同期出生的新生儿分为正常组和窒息组,并分别分为正常体重及低体重组。应用酶联免疫吸附实验方法检测血清中Hcy水平。应用放射免疫法测定血中叶酸浓度。结果窒息组正常体重儿血清同型半胱氨酸为(10.50±2.19)μmol/L,低体重儿为(15.82±2.51)μmol/L,对照组正常体重儿血清同型半胱氨酸为(7.73±0.61)μmol/L,低体重儿为(7.45±0.43)μmol/L。在窒息组内低体重儿血清同型半胱氨酸水平明显高于正常体重儿(P<0.001),且窒息低体重组儿血清同型半胱氨酸水平明显高于正常对照组儿,不论其出生体重如何(P<0.001)。血清叶酸水平检测结果显示窒息组正常体重儿血清叶酸水平为(2.74±0.16)μg/L,低体重儿为(2.29±0.25)μg/L,对照组正常体重儿血清叶酸为(3.33±0.23)μg/L,低体重儿为(3.02±0.29)μg/L。窒息组患儿无论正常体重儿还是低体重儿其血清叶酸水平变化均不显著(P>0.05)。结论缺氧窒息合并低出生体重者血清同型半胱氨酸水平显著升高。  相似文献   
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