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101.
Trisomy 8/8q is a common cytogenetic event in myelocytic malignancies, ranging from myelodysplastic syndrome (MDS) to acute myelocytic leukemia (AML) to blastic transformation of chronic myelocytic leukemia. Isochromosome 8q results in the same gene dosage effect. Duplication of i(8q), resulting in pentasomy 8q, has been reported only in two cases of AML. A patient with fibrosing alveolitis on prolonged cyclophosphamide treatment developed therapy-related MDS. Karyotyping, FISH, and CGH analysis showed a duplicated i(8q) among other complex abnormalities. The clinical features of 11 cases of myelocytic leukemia with pentasomy and hexasomy 8/8q were summarized. Compared with trisomy and tetrasomy 8, significant features included reduced median survival (90 days), treatment refractoriness (even with transplantation), monocytic differentiation, trilineage dysplasia, and radiation or toxin exposure. Increasing copy numbers of chromosome 8/8q may therefore be a marker of advanced leukemic evolution, exposure to toxins, underlying myelodysplasia, and an overall poor prognosis. 相似文献
102.
Li Wan Xiaoping Zhang Simi Gunaseelan Shahriar Pooyan Olivia Debrah Michael J Leibowitz Arnold B Rabson Stanley Stein Patrick J Sinko 《AIDS research and therapy》2006,3(1):12-15
Background
Current anti-AIDS therapeutic agents and treatment regimens can provide a dramatically improved quality of life for HIV-positive people, many of whom have no detectable viral load for prolonged periods of time. Despite this, curing AIDS remains an elusive goal, partially due to the occurrence of drug resistance. Since the development of resistance is linked to, among other things, fluctuating drug levels, our long-term goal has been to develop nanotechnology-based drug delivery systems that can improve therapy by more precisely controlling drug concentrations in target cells. The theme of the current study is to investigate the value of combining AIDS drugs and modifiers of cellular uptake into macromolecular conjugates having novel pharmacological properties. 相似文献103.
基于扩展Infomax ICA的ERP少次提取方法研究 总被引:1,自引:0,他引:1
事件相关电位(event related potential,ERP)提取是脑电研究的重点之一,目前临床上主要通过相干平均的方法来获取.由于脑电的非平稳性,使其需要大量重复刺激才能获得,对于受试者极不方便,也不利于ERP的实时检测.本文以反映大脑稀少认知事件的相关电位P300为例,采用扩展Infomax(extended informationmaximization)独立分量分析(independent component analysis,ICA)算法,先滤除眼动、工频干扰,再重构脑电数据,最后经少次叠加即可得到与通常需多次相干平均结果相近的比较满意的P300波形.说明ICA算法在ERP的峰值和潜伏期模式识别上具有较为明显的效果,具有潜在的临床工程应用价值. 相似文献
104.
The role of mPer1 in morphine dependence in mice 总被引:6,自引:0,他引:6
Liu Y Wang Y Wan C Zhou W Peng T Liu Y Wang Z Li G Cornelisson G Halberg F 《Neuroscience》2005,130(2):383-388
Investigations using Drosophila melanogaster have shown that the circadian clock gene period can influence behavioral responses to cocaine, and the mouse homologues, mPer1 and mPer2, modulate cocaine sensitization and reward. In the present study, we applied DNAzyme targeting mPer1 to interfere the expression of mPer1 in CNS in mice and studied the role of mPer1 on morphine dependence. We found that the DNAzyme could attenuate the expression of mPer1 in CNS in mice. Mice treated with DNAzyme and morphine synchronously did not show preference to the morphine-trained side, whereas the control group did. In contrast, mice treated with DNAzyme after morphine showed preference to the morphine-trained side as well as the control group did. These results indicate that drug dependence seems to be influenced at least partially by mPer1, but mPer1 cannot affect morphine dependence that has been formed. 相似文献
105.
106.
目的通过石灰水对埃及伊蚊生活史幼期不同阶段生长发育影响的实验室研究,评价生石灰对防治埃及伊蚊的干预效果,为生石灰用于埃及伊蚊的防治提供实验数据。方法将一定数量的埃及伊蚊依据不同发育阶段(卵、Ⅰ~Ⅳ龄期蚊幼、蛹)分别饲养于石灰水中,观察蚊幼活动情况,记录不同时期相应孵化时间、孵化率和死亡率,同时将实验室过夜自来水(实验室脱氯水)饲养蚊虫作对照,分析比较不同饲养环境、不同发育阶段埃及伊蚊发育的变化差异。结果对照组埃及伊蚊卵的平均孵化时间为1.75 d,而试验组(1.3 g/L石灰水饲养)埃及伊蚊卵的平均孵化时间为3.84 d,是对照组的2.19倍,孵化时间的差异具有统计学意义(t=36.02,P<0.05)。试验组埃及伊蚊卵孵化率为59.3%,对照组为89.3%,两组之间孵化率的差异具有统计学意义(χ^(2)=35.38,P<0.05)。Ⅰ~Ⅳ龄试验组蚊幼死亡率分别为44.0%、92.0%、97.3%、98.7%,显著高于对照组蚊幼死亡率,两组之间死亡率的差异具有统计学意义(χ^(2)值为65.79~276.53,P<0.05)。试验组蛹的死亡率为98.7%,显著高于对照组的死亡率,两组之间死亡率的差异具有统计学意义(χ^(2)=280.35,P<0.05)。对照组埃及伊蚊卵、蚊幼和蛹的死亡率分别为10.7%、2.3%和2.0%,三组之间死亡率的差异具有统计学意义(χ^(2)=25.09,P<0.05)。对照组埃及伊蚊卵的死亡率明显高于蚊幼和蛹。试验组埃及伊蚊卵、蚊幼和蛹的死亡率分别为40.7%、83.0%和98.7%,三组之间死亡率差异具有统计学意义(χ^(2)=170.88,P<0.05)。结论石灰水对埃及伊蚊不同发育阶段均具有明显抑制作用,对蛹的杀灭作用最大,其次是蚊幼和卵。随着埃及伊蚊幼虫年龄的增长,石灰水对其抑制效果逐渐增强。但生石灰对埃及伊蚊成蚊的防治效果有待进一步的现场验证。 相似文献
107.
Ching Shan Wan Jade Mitchell Andrea B. Maier 《Journal of the American Medical Directors Association》2021,22(6):1331.e1-1331.e9
ObjectivesTo evaluate the effect of Hospital Admission Risk Program (HARP) on unplanned hospitalization, bed days, and mortality of enrolled individuals and to evaluate the cost-effectiveness of HARP.DesignA retrospective longitudinal analysis of hospital administrative data.InterventionIndividuals at risk of hospitalization were provided with multidisciplinary, community-based care support managed by care coordinators including integrated care planning, education, monitoring, service linkages, and general practitioner liaison over 6-9 months.Setting and ParticipantsIndividuals who were enrolled into 1 of 8 HARP chronic disease management programs between July 1, 2017, and June 30, 2018, at the Royal Melbourne Hospital, Australia.MethodsHospital admissions between 18 months before and 18 months after HARP enrollment were analyzed. Total hospital costs were compared between 18 months before and 12 months after HARP enrollment.ResultsA total of 1553 individuals with a median age of 71 years (interquartile range 60-81), 63.4% males, were admitted to HARP. Both unplanned hospitalizations and bed days were reduced during the HARP intervention compared to within 3 months before enrollment in each of the HARP management programs. After the HARP intervention, cardiac coach, cardiac heart failure, chronic respiratory, diabetes comanagement, and medication management programs had higher hospitalizations and bed days than individuals’ baseline of at least 3 months before HARP enrollment. Individuals in cardiac heart failure and chronic respiratory management programs had a higher mortality rate than other HARP chronic disease management programs. Individuals in cardiac coach, diabetes comanagement, and medication management programs had lower hospital costs during the HARP intervention compared to within 3 months before HARP enrollment.Conclusions and ImplicationsHARP reduced unplanned hospitalization and bed days but did not return individuals’ hospital use to baseline before the intervention. The variations in mortality between HARP chronic disease management programs implies that condition-specific goals between programs is preferable. 相似文献
108.
Pyoeng Gyun Choe Chang Kyung Kang Hyeon Jeong Suh Jongtak Jung Kyoung-Ho Song Ji Hwan Bang Eu Suk Kim Hong Bin Kim Sang Won Park Nam Joong Kim Wan Beom Park Myoung-don Oh 《Emerging infectious diseases》2021,27(1):327
We investigated the kinetics of severe acute respiratory syndrome coronavirus 2 neutralizing antibodies in 7 asymptomatic persons and 11 patients with pneumonia. The geometric mean titer of neutralizing antibodies declined from 219.4 at 2 months to 143.7 at 5 months after infection, indicating a waning antibody response. 相似文献
110.
目的:探讨治疗创伤对高血压性脑出血患者血糖及按期预后的影响。方法:采用局麻血肿穿刺抽吸治疗(治疗组32例)及全麻外科手术血肿清除治疗(对照组30例),比较术后的血糖变化,结果:治疗组血肿穿刺抽吸后血糖高峰值水平显著低于对照组(P<0.01),而治疗后第1,2,周血糖降至正常者治疗组显著高于对照组(P<0.05),病死率治疗组6.25%,对照组26.7%),两组比较差异显著(P<0.05),结论:高血压性脑出血患者血肿穿刺抽吸治疗较外科手术血肿清除治疗有血糖峰值低,恢复正常的速度快,病死率低,对脑组织的损伤小等优点,值得临床推广。 相似文献