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排序方式: 共有1171条查询结果,搜索用时 15 毫秒
91.
急性淋巴细胞白血病(上) 总被引:2,自引:0,他引:2
急性淋巴细胞白血病是淋巴前体细胞异常引起的恶性疾病,儿童与成人均可能发生。儿童发病高峰2~5岁。有效治疗的稳步进展使本病在儿童中的治愈率80%以上,同时为新的治疗方案提供了良机,新方案将保留我们在白血病无病生存病例中获得的治疗经验,同时减轻当前强化治疗方案中的毒副作用。 相似文献
92.
冠心病合并2型糖尿病患者血脂检测 总被引:1,自引:0,他引:1
目的:观察冠心病(CHD)合并2型糖尿病患者血脂水平的变化,并探讨CHD合并2型糖尿病的危险性与脂质代谢紊乱间的相关性.方法:检测CHD组患者29(男18,女11)例,年龄40~70(平均55.2)岁;CHD合并2型糖尿病组[CHD伴非胰岛素依赖型糖尿病(NIDDM)]患者22(男12,女10)例,年龄41~70(平均56.5)岁;正常对照组[健康献血员31(男17,女14)例,年龄38~50(平均43.5)岁]的血脂水平.结果:CHD伴NIDDM组患者总胆固醇(TC),三酰甘油(TG),低密度脂蛋白胆固醇(LDLC)和载脂蛋白B(ApoB)水平明显高于CHD组患者[TC:(5.87±1.02)mmol/Lvs(4.10±1.13)mmol/L;TG:(2.10±1.05)mmol/Lvs(1.13±0.85)mmol/L;LDLC:(4.23±0.97)mmol/Lvs(2.97±0.90)mmol/L;ApoB:(0.90±0.18)mmol/Lvs(0.58±0.19)mmol/L,均P<0.01],但CHD伴NIDDM组患者高密度脂蛋白胆固醇(HDLC),载脂蛋白A1(ApoA1)水平明显低于CHD组患者[HDLC(0.71±0.12)mmol/Lvs(0.94±0.16)mmol/L,ApoA1:(0.73±0.19)mmol/Lvs(1.03±0.20)mmol/L,均P<0.01].结论:CHD合并2型糖尿病患者在脂质代谢紊乱方面存在更多致CHD的危险因素,应重视这类患者的血脂检测并及时纠正脂质代谢紊乱,以降低CHD的危险性. 相似文献
93.
无环鸟苷亲脂性前体药物脂质体的制备及体外抗病毒活性(英文) 总被引:2,自引:0,他引:2
本文通过将无环鸟苷(acyclovir,简称ACV)2’位羟基分别与月桂酰氯或棕榈酰氯进行酯化反应,制得亲脂性前体药物无环鸟苷月桂酸酯和无环鸟苷棕榈酸酯(分别简称为C12-ACV和C16-ACV),使脂质体包封率从ACV的29.9%提高到C12-ACV的95.6%和C16-ACV的97.1%;漏泄实验表明在4℃透析60h后,一半以上的ACV从脂质体中漏泄,而C12-ACV和C16-ACV的滞留率分别为70%和80%;体外抗疱疹病毒的试验中,在最低试验浓度0.044μmol/L时,ACV不显示抗病毒活性,而C16-ACV脂质体抑制细胞病变率达75%,说明前体药物通过与脂质体脂膜的结合增加了药物的进入细胞能力,从而提高了ACV的抗病毒能力。 相似文献
94.
SUMMARY: Peritonitis and exit‐site infections remain the most important limitations to the delivery of continuous ambulatory peritoneal dialysis (CAPD). Contamination of the peritoneum, from endogenous or exogenous sources, is responsible for most peritonitis episodes. Patients usually present with a cloudy bag, although other causes should be distinguished. Clinical suspicion of peritonitis should be followed rapidly by microbiological examination and empirical treatment. Microbiological confirmation allows for subsequent treatment based on sensitivities. Other interventions such as catheter removal may be appropriate in some patients. Exit‐site infections should also be identified and treated early. Peritonitis may be further prevented by adequate exit‐site care, hygienic methods, and techniques to minimise early contamination of the exit site. Mupirocin may also have a role in preventing infections caused by Staphylococcus aureus. 相似文献
95.
Rapparini C Saraceni V Lauria LM Barroso PF Vellozo V Cruz M Aquino S Durovni B 《The Journal of hospital infection》2007,65(2):131-137
Healthcare workers (HCWs) frequently face the risk of occupational infection from bloodborne pathogens following exposure to blood and body fluids. This study describes the results of a surveillance system of occupational exposure to bloodborne pathogens among HCWs in Rio de Janeiro, Brazil, during an eight-year period. A total of 15 035 exposures reported from 537 health units were reviewed. Six circumstances comprised nearly 70% of the reported exposures: recapping needles (14%), performing surgical procedures or handling surgical equipment (14%), handling trash (13%), during disposal into sharps containers (13%), performing percutaneous venepuncture (10%) and during blood drawing (5%). Easily preventable exposures, such as incidents related to recapping needles, handling trash, and sharps left in an inappropriate place, represented 30% of the exposures reported. Post-exposure prophylaxis (PEP) for human immunodeficiency virus (HIV) was initiated for 46% of exposed HCWs. Although Brazilian guidelines indicate that PEP is usually not recommended for exposures with insignificant or very low risk of HIV infection, PEP was prescribed to a large proportion of exposed HCWs under these circumstances. The prevention of occupational exposure to bloodborne pathogens among HCWs and their safety must be considered as a public health issue. Although infection-preventative measures such as antiretroviral drugs and rapid tests are available, this study shows that there are still a high number of easily preventable exposures. The implementation of more effective prevention strategies is urgently required in this country. 相似文献
96.
目的 研究Ewing’s肉瘤细胞系 (RM 82 )X 射线外照射后肿瘤坏死因子 (TNF α)和转化生长因子 (TGF β)mRNA表达水平的变化 ,探讨X 射线诱导内源性TNF α和TGF β产生的可能性及意义。 方法 应用实时荧光RT PCR ,检测接受不同剂量X 线照射 (2Gy ,5Gy ,10Gy ,2 0Gy ,30Gy ,4 0Gy)和受照后不同时间 (1h ,3h ,6h ,12h ,2 4h ,4 8h ,72h)。TNF α和TGF βmRNA表达水平的变化。 结果 RM 82细胞TNF αmRNA表达水平较外照射前显著升高。一方面受照后TNF αmRNA表达逐渐升高 ,照射剂量达 4 0Gy时TNF αmRNA表达水平达高峰 ,为正常对照组的 10 8倍 ;另一方面 ,照射后 3h后TNF αmRNA表达逐渐升高 ,6h达高峰 ,为正常对照组的 18倍。相反 ,TGF βmRNA表达水平X 射线照射前后无显著变化。结论 Ewing’s肉瘤细胞系 (RM 82 )接受X 线照射后TNF αmRNA表达明显升高 ,且呈现时间、剂量依赖性。放射治疗可诱导Ewing’s肉瘤细胞系 (RM 82... 相似文献
97.
98.
丹酚酸A对大鼠半乳糖性白内障形成的抑制作用 总被引:20,自引:0,他引:20
业已证明,丹酚酸A有较强的抗氧化和清除自由基等多方面的作用。本实验用大鼠半乳糖性白内障模型,研究局部应用丹酚酸A对白内障形成的影响。结果表明,局部用0.05%的丹酚酸A(每日滴眼两次)对白内障的形成有一定的抑制作用,使白内障形成过程减缓。而且给药组动物晶体内过氧化氢和脂质过氧化产物(MDA)含量减少,蛋白巯基和总巯基增加。体外实验表明,丹酚酸A对醛糖还原酶有一定抑制作用。以上结果提示,丹酚酸A可通过不同途径抑制白内障的形成,对糖性白内障的防治有一定意义。 相似文献
99.
Human burst-forming units-erythroid need direct interaction with stem cell factor for further development 总被引:6,自引:3,他引:6
To understand the factors that regulate the early growth and development of immature erythroid progenitor cells, the burst-forming units-erythroid (BFU-E), it is necessary to have both highly purified target cells and a medium free of serum. When highly purified human blood BFU-E were cultured in a serum-free medium adequate for the growth of later erythroid progenitors, BFU-E would not grow even with the addition of recombinant human interleukin-3 (rIL-3), known to be essential for these cells. However, the addition of recombinant human stem cell factor (rSCF), which supports germ cell and pluripotential stem cell growth, stimulated BFU-E to grow equally well in serum-free as in serum-containing medium. Limiting dilution studies showed that rSCF acts directly on the BFU-E that do not require accessory cells for growth. Furthermore, rSCF was necessary for BFU-E development during the initial 7 days of culture, until these cells reached the stage of the late progenitors, the colony-forming units-erythroid (CFU-E). These studies indicate that early erythropoiesis is dependent on the direct action of SCF that not only affects early stem cells but is continually necessary for the further development of committed erythroid progenitor cells until the CFU-E stage of maturation. 相似文献
100.