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991.
目的:探讨三氧化二砷(As2O3) 治疗慢性粒细胞性白血病(CML) 的机制。方法:以CML细胞系K562 为模型,通过细胞增殖、活力检测、形态学观察、肿瘤集落形成的琼脂糖凝胶电泳等检验。结果:经≥2.5μmol/LAs2O3 处理的K562 细胞可出现增殖受抑和凋亡的形态学改变及DNA片段化。结论:As2O3 能有效地诱导K562 细胞凋亡。 相似文献
992.
目的建立用斑点免疫金渗滤试验(DIGFA)检测血请中登革病毒抗原的方法。方法一株DV4型特异性单克隆抗体点加于硝酸纤维膜上,以捕获血清中的DV4抗原。借助黄病毒组反应性单克隆抗体、生物素化革抗鼠IgG抗体、金标SPA和金标亲合素,建立用DIGFA检测血清中登革病毒抗原的方法。结果常规DIGFA检测的敏感性高于病毒分离,而生物素一亲合素DIGFA(BA-DIGFA)的敏感性又高于常规的DIGFA。常规DIGFA可检测到5、0TCID50的病毒抗原,BA-DIGFA可检测到43TCID50的病毒抗原。结论作者建立的BA-DIGFA简便、快速、敏感、特异,可用于快速诊断登革病毒4型感染。 相似文献
993.
Alzheimer's disease is characterized by the tissue deposition of beta-amyloid peptide (Abeta) in the brain. Recent studies have shown apoproteins (apo) in amyloid plaques and associated with high-density lipoprotein (HDL) particles in the cerebrospinal fluid (CSF). Western blot analysis revealed that serum amyloid A (apoSAA) protein was present in control and AD patients at low levels compared to apoE and apoA-I, however, AD brains showed a significant increase over control values. Analysis of CSF-HDL from control and AD individuals showed that apoA-I, apoE and apoSAA were on the particle. Immuno-cytochemical analysis showed that SAA was detected in senile plaques in AD tissue, but was predominantly localized to neuritic plaques. ApoE staining of AD brain confirmed that most plaques contained the apoprotein, similar to Abeta immunoreactivity, whereas apoA-I expressed little staining of senile plaques. No significant differences were detected in the level of apoSAA when compared to APOE genotype in AD samples, suggesting that interactions with apoE were non-specific. These data imply that the specific interactions of SAA with Abeta in the neuritic plaques may play a role in AD. 相似文献
994.
Rapid induction of cytokine gene expression in the lung after single and fractionated doses of radiation 总被引:4,自引:0,他引:4
Hong JH Chiang CS Tsao CY Lin PY McBride WH Wu CJ 《International journal of radiation biology》1999,75(11):1421-1427
PURPOSE: To investigate cytokine gene expression in the lung after single and fractionated doses of radiation, and to investigate the effect of steroids and the genetic background. MATERIALS AND METHODS: Expression of cytokine genes (mTNF-alpha, mIL-1alpha, mIL-1beta, mIL-2, mIL-3, mIL-4, mIL-5, mIL-6, mIFN-gamma) in the lungs of C3H/HeJ and C57BL/6J mice was measured by RNase protection assay at different times after various doses of radiation. The effects of dexamethasone and fractionated radiation treatment on gene expression were also studied. RESULTS: IL-1beta was the major cytokine induced in the lungs of C3H/HeJ mice within the first day after thoracic irradiation. Radiation doses as low as 1 Gy were effective. Responses to 20 Gy irradiation peaked within 4-8h and subsided by 24 h. With the exception of IL-1alpha and TNF-alpha, the other cytokines that were investigated had undetectable pre-treatment mRNA levels and were not radiation inducible. Similar responses were seen in C57BL/6J mice, although TNF-alpha was induced and there were some quantitative differences. Pre-treatment of C3H/HeJ mice with dexamethasone reduced basal and induced IL-1 levels, but complete inhibition was not achieved. Dexamethasone was also effective if given immediately after irradiation. Fractionated daily doses of radiation (4 Gy/day) helped to maintain cytokine gene expression for a longer period. CONCLUSIONS: Inflammatory genes are rapidly induced in the lung by irradiation. This response cannot be readily abolished by steroid pre-treatment. Fractionated treatment schedules help to perpetuate the response. 相似文献
995.
BACKGROUND/AIM: A mechanism suggested to cause injury to preserved organs is the generation of oxygen free radicals. Lipid peroxidation is one of the biological damages caused by oxygen free radicals. It is our aim to investigate whether magnolol, a strong antioxidant, suppresses the generation of oxygen free radicals and improves the viability of cold-preserved warm-reperfused rat livers. MATERIALS AND METHODS: In vitro lipid peroxidation was induced in rat hepatic mitochondria with ADP and FeSO4. The inhibitory effect of magnolol on lipid peroxidation was measured with oxygen consumption and malondialdehyde (MDA) formation. Subsequently, we preserved and reperfused rat livers in preservation solutions that contained magnolol. The hepatic enzymes and liver MDA were measured to assess the protective effect of magnolol on isolated rat livers. RESULTS: In rat hepatic mitochondria, magnolol was 470 times more potent than alpha-tocopherol in inhibiting oxygen consumption and 340 times more potent than alpha-tocopherol in inhibiting MDA formation. Addition of magnolol to Ringer's lactate solution had a protective effect, in terms of MDA formation and leakage of hepatic enzymes, on warm-reperfused but not cold-stored liver tissue. Addition of magnolol to University of Wisconsin (UW) solution, a widely used preservation solution, did not modify the effect of this solution on isolated liver tissues. CONCLUSIONS: We conclude that magnolol is an effective antioxidant and suppresses lipid peroxidation in rat liver mitochondria and can be used as a rinsing solution in protecting transplanted organs from lipid peroxidation during reperfusion, especially for those organs not preserved with UW solution. 相似文献
996.
Chiu HJ Tsai SJ Chen JY Lin CY Bai YM Song HL Lai HC Hong CJ 《Psychiatry research》1999,87(2-3):245-248
We investigated the association between schizophrenic psychosis and an intronic polymorphism of the presenilin-1 (PS1) gene in a Chinese population. Schizophrenic and control groups had similar PS1 genotype distributions and allele frequencies, indicating that this polymorphism may not be involved in the development of schizophrenia. 相似文献
997.
We report a girl who developed severe and fatal hyperkalemia following rapid and massive blood transfusion during surgery. She was 7-year-old, 20-kg in weight, and received wide resection of the femoral bone with custom prosthesis implant because of malignant femoral osteosarcoma. During the procedure, bleeding was active and profuse and amounted to about 3,000 mL in 4 h, eventuating in shock. Despite rapid transfusion with 15 units of packed red blood cells (RBC) still she remained hypotensive and hypovolemic. When we switched to give her whole blood, actually 100 mL having been given, widening of QRS complex followed immediately by cardiac arrest developed. Cardiopulmonary resuscitation although started at once was unsuccessful. At this juncture, arterial blood gas analysis showed acidosis and severe hyperkalemia (10.3 mmol/L), possibly resulting from transfusion of blood of older storage. The case reminded us once again the importance and necessity of the use of potassium-low blood component (fresh, saline-washed RBCs) in case of massive and rapid blood transfusion especially in pediatric patients with hypovolemia and low cardiac output. 相似文献
998.
999.
医院固定资产管理存在的问题及对策 总被引:20,自引:2,他引:18
赵红 《中华医院管理杂志》1999,15(6):381-383
目前,医院的固定资产管理中存在着:一是责权问题,即账物不清,产权不清,移交不清。二是工作制度问题,即账反映不真实、残值不入账、盘盈盘亏处理不当、盲目购置等。解决上述问题的策略:①做好产权的界定和登记;②建立有效的管理机构;③完善和实施各项固定资产管理的制度。 相似文献
1000.