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61.
用吐温80-乙醚(TE)法、蔗糖-丙酮(SA)法、丙酮-乙醚(AE)法分别从肾综合征出血热病毒(HFRSV)感染的Vero-E6细胞培养和乳小白鼠脑组织中制备病毒血凝素(HAN),定量对比证明其制备效果,结果无明显差异。粗制HAN经高压液相色谱(EPLC)纯化,有4个洗脱峰,血凝活性物质存在于峰1。纯化HAN在SDS-PAGE中呈单一区带,分子量56.6KD,HAN相对含量79.6%。纯化HAN在蔗糖密度梯度液中有一条1.15~1.16g/cm3的沉淀,粗制HAN有3条沉淀。电镜观察纯化HAN中为大小相等的球状颗粒。粗制HAN的高密度沉淀中可见到病样颗粒。对几种常用消毒剂、氧化剂、去垢剂对HAN的灭活作用做了实验对比观察。 相似文献
62.
PHARMACOKINETICSOFCUPRIC-BIS(SALICYLALDEHYDE-2-FURANTHIOCARBOXY-HYDRAZONATE)DICHLORIDE(CSFTCH)INRABBITS¥GaoYunsheng;ZhuYuyun(... 相似文献
63.
Stefan Farese Kushiar Shojaati Bert Kadereit Felix J Frey Markus G Mohaupt 《Nephrology, dialysis, transplantation》2006,21(7):1984-1987
Volume expansion in the presence of elevated aldosterone availabilityis a hallmark of normal pregnancy. Intravascular volume depletioncharacterizes severe pregnancy-associated disease conditionssuch as intra-uterine growth retardation, chronic hypertensionor pre-eclampsia [1]. Two hypotheses have been forwarded toexplain volume depletion in pregnancy: the first hypothesischarges inappropriate sensing of vascular overfilling,resulting in an increased transendothelial loss of fluid tothe extravascular compartment. In contrast, the second hypothesisfocuses on vascular underfilling due to inappropriatelylow aldosterone levels. The second hypothesis is based on theassumption that a compensatory increase in the circulating fluidvolume is required in normal pregnancy to support fetal substratedelivery. According to the second concept, maternal blood pressureincreases due to counter-regulatory mechanisms when placentalblood supply is reduced [2]. In support of the underfillinghypothesis are observations that a 相似文献
64.
A cohort mortality study among cobalt and sodium workers in an electrochemical plant 总被引:3,自引:0,他引:3
J M Mur J J Moulin M P Charruyer-Seinerra J Lafitte 《American journal of industrial medicine》1987,11(1):75-81
We have studied the mortality between 1950 and 1980 of a cohort of 1,143 workers in an electrochemical plant producing cobalt and sodium. The mortality of the whole cohort is significantly lower than in the French population for all causes of death (SMR = 0.77), and especially for deaths from circulatory system diseases (SMR = 0.59). However, among cobalt production workers, there is a relative over-mortality, especially from lung cancers (SMR = 4.66, 4 cases). The relationship between cobalt production and lung cancer mortality was supported by a case-control study nested in the cohort study. The authenticity of the occupational origin of this risk could not be established due to the low number of cases and because the role of tobacco consumption could not be taken into account. Other studies should be carried out in plants producing or using cobalt. 相似文献
65.
66.
2%HPMC对兔眼内压及角膜内皮影响的实验研究 总被引:5,自引:0,他引:5
报导了2%羟丙基甲基纤维素(HPMC)、1%透明质酸钠(Na-HA)及平衡盐液(BSS)分别注入兔眼前房后,其眼内压、角膜内皮细胞数及内皮细胞形态的变化。证实自制2%HPMC 与进口1%Na-HA 性能基本相同,仅有一过性眼压升高,不损害角膜内皮,能在眼前节手术及人工晶体植入时有效地保护角膜内皮细胞。 相似文献
67.
Michael S NOBES Carol A POLLOCK Pan T HENG Michaelj FIELD 《Nephrology (Carlton, Vic.)》1995,1(4):277-283
Summary: The present studies assessed the effects of manipulating extracellular sodium (Na) concentration and Na transport on cellular hypertrophy and hyperplasia in primary culture of rat proximal tubular cells. A concentration-dependent effect on thymidine incorporation and protein content was observed with cell culture media Na concentration of 130, 140 and 150 mmol/L. This effect was independent of osmolality (matched with mannitol) and no stimulatory effect occurred if choline was substituted for Na. Cells derived from sham-operated (Sx) animals exposed to a higher media concentration of Na (150 vs 140 mmol/L) had both stimulated thymidine incorporation to 186.8 ± 35.41% (P<0.05) and enhanced cell protein content to 134.7 ± 135% (P<0.05). This effect was more pronounced in cell cultures derived from unilaterally nephrectomized (Nx) animals, being 212.8 ± 31.5% (P<0.01) for thymidine incorporation (P<0.05 vs cells from sham-operated animals grown in high Na media) and 114.4 ± 3.2% (P<0.001) for protein content (P=0.11 vs sham-operated cells grown in similar conditions). the addition of 10?4 mmol/L ethylisopropyl amiloride hydrochloride (EIPA) to Nx cells in a normal or high Na concentration media resulted in a decrease in cellular protein content to 82.6 ± 6.8% (P<0.05) and 85.5 ± 0.2% (P<0.0001) compared to respective controls. 10?4 mol/L EIPA in media supplemented with insulin-like growth factor (IGF-1) blocked the proliferative response normally seen in response to this growth factor from 156.6 ± 13.7 to 27.5 ± 3.1% (P<0.0001) compared to control. However, the presence of EIPA did not abrogate the hypertrophic response elicited by IGF-1 (cell protein content 128.1 ± 13.1% of control with IGF-1 vs 124.9 ± 12.5 with IGF-1 and EIPA; P= n.s.). Addition of 10?4 mol/L EIPA to 10% serum derived from either Sx or Nx animals blocked the growth response to the sera, limiting the cellular protein content to 76.6 ± 5.5% (P<0.0001) and 89.7 ± 4.4% (P<0.0001) and thymidine incorporation to quiescent levels of 0.2 ± 0.1% (P<0.0001) and 0.4 ± 0.1% (P<0.0001) compared to respective controls. In summary, rat renal proximal tubular cell growth is influenced by Na concentrations in the cell culture environment and inhibited in the presence of EIPA. This supports a role for altered epithelial transport in the cellular growth response to a number of stimuli. 相似文献
68.
高效液相色谱法测定硫酸奈替米星注射液的含量 总被引:4,自引:0,他引:4
目的采用高效液相色谱法测定硫酸奈替米星及注射液的含量。方法以μ-Diamonsil—C18为分析柱,流动相为1.5%的磷酸二氢钾-乙睛,流速为1.0ml/min,检测渡长为205nm。含量测定用峰面积外标法。结果硫酸奈替米星在0.1—1.6mg/ml浓度范围内呈现良好线性关系,r=0.9998.平均回收率为99.5%,RSD=0.4%(n=9)。结论本方法操作简便、快速,结果准确可靠,重现性好,均能很好地满足质量控制的要求,为开辟氨基糖苷类抗生素含量测定的仪器提供了一定借鉴。 相似文献
69.
70.
高迁移率族蛋白B1对大鼠脾脏树突状细胞表面共刺激分子表达的影响 总被引:10,自引:1,他引:9
目的观察高迁移率族蛋白B1(HMGB1)对树突状细胞(dendritic cells,DC)表面共刺激分子表达的影响,并对其机制进行初步探讨。方法分离正常Wistar大鼠脾脏DC后置于96孔培养板(1×10~5/孔),采用HMGB1刺激,观察HMGB1刺激与DC表面共刺激分子CD80、CD86和主要组织相容性复合物(MHC)Ⅱ表达的时间-效应关系及剂量-效应关系。结果HMGB1刺激后,DC表面共刺激分子CD80、CD86和MHCⅡ表达分别于24~72 h明显上调(P<0.05,0.01),其中以作用48 h后DC表面共刺激分子表达上调尤为显著(P<0.01);0.1μg/ml、1μg/ml、10μg/ml的HMGB1刺激均可诱导DC表面共刺激分子CD80、CD86和MHCⅡ表达增强(P<0.05,0.01),其中HMGB1的浓度在1μg/ml时,大鼠DC表面共刺激分子CD80、CD86和MHCⅡ的表达增强最明显(P<0.01)。结论HMGB1能诱导DC表面共刺激分子表达增强,HMGB1可能是诱导DC成熟的免疫刺激信号。 相似文献