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161.
mRNA差异显示法筛选和克隆胎肝中差异表达基因   总被引:1,自引:1,他引:0  
张俊杰  陈南春  陈苏民 《医学争鸣》2000,21(12):S242-S242
0 引言 胎肝正处于生长发育阶段 ,其中表达的一些基因在成人肝脏中处于关闭状态 ,当成人肝脏部分切除或肝细胞广泛受损时 ,剩余肝细胞表现出很强的再生能力 ,再生成年肝脏和肝癌细胞中都出现有发育早期基因的表达 [1 ] .克隆这类胎肝中差异表达的基因 ,将有助于了解肝脏的发育过程 ,并为肝脏再生及肝脏相关疾病的研究提供线索 .1 材料和方法1.1 材料 胎肝和成人肝组织分别由西京医院妇产科和肝胆外科提供 .差示 PCR引物为 5′端 10碱基随机引物 I(RPI) :5′- AGCCACCATG- 3′ ;5′端 10碱基随机引物 II(RPII) :5′- TAGCAG…  相似文献   
162.
Purpose.?To evaluate the psychometric and administrative properties of outcome measures in the ICF Participation category, which are used in stroke rehabilitation research and reported in the published literature.

Method.?Critical review and synthesis of measurement properties for six commonly reported instruments in the stroke rehabilitation literature. Each instrument was rated using the eight evaluation criteria proposed by the UK Health Technology Assessment (HTA) programme. The instruments were also assessed for the rigour with which their reliability, validity and responsiveness were reported in the published literature.

Results.?Validity has been well reported for at least half of the measures reviewed. However, methods for reporting specific measurement qualities of outcome instruments were inconsistent. Responsiveness of measures has not been well documented. Of the three ICF categories, Participation seems to be most problematic with respect to: (a) lack of consensus on the range of domains required for measurement in stroke; (b) much greater emphasis on health-related quality of life, relative to subjective quality of life in general; (c) the inclusion of a mixture of measurements from all three ICF categories.

Conclusions.?The reader is encouraged to examine carefully the nature and scope of outcome measurement used in reporting the strength of evidence for improved participation associated with stroke rehabilitation. There is no consensus regarding the most important indicators of successful involvement in a life situation and which ones best represent the societal perspective of functioning. In particular, quality of life outcomes lack adequate conceptual frameworks to guide the process of development and validation of measures.  相似文献   
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BackgroundEar related diseases are commonly seen in clinics worldwide especially among children. They are associated with significant morbidity and frequent hospital visits. Limited data exists regarding the burden of ear disease among Nigerian children.ObjectiveTo determine the prevalence of ear-related problems among children presenting at the Paediatric and Otorhinolaryngology clinics of the University of Nigeria Teaching Hospital, Enugu.ResultsThree thousand and twenty-one children were seen during the study period. Out of these, 248 children (8.2%) presented with ear-related problems. Chronic otitis media (30.5%), acute otitis media (29.9%), cerumen auris (11.3%), otitis externa (10.1%), hearing impairment (7.3%) and foreign body in the ear (5.7%) were the most commonly diagnosed ear-related problems.ConclusionEar-related problems among children presenting at the UNTH Enugu were not uncommon. However, otitis media was the most commonly diagnosed ailment affecting the ears in children.  相似文献   
165.
The influence of dosage time of midazolam on its pharmacokinetics and effects on the central nervous system were investigated in six healthy volunteers, with pharmacokinetic-pharmacodynamic modeling. Each volunteer received single oral doses of 15 mg midazolam on four separate occasions: 8 AM, 2 PM, 8 PM, and 2 AM. An almost significant circadian variation was found in elimination half-life, shortest at 2 PM (1.26 +/- 0.47 hours, mean +/- SD) and longest at 2 AM (1.57 +/- 0.44 hours) (p = 0.05). Drug effects measured were alpha activity of the electroencepalograph and P100 latency of the visual-evoked response. The maximum drug effect (Emax) model described the concentration-effect relationship, extended with either a threshold drug concentration or a sigmoidicity parameter. A significant circadian variation was found in baseline alpha activity: highest at 8 AM (109% +/- 19% of the 24-hour mean) and lowest at 2 AM (80% +/- 12%). For alpha activity the drug concentration at half-maximum effect of both threshold Emax model and sigmoid Emax model showed lower values at 8 AM and 2 AM and higher values at 2 PM and 8 PM. However, these differences were either not significant (p = 0.10, threshold model) or on the verge of statistical significance (p = 0.05, sigmoid model). No circadian variation was found in the parameters describing the effect on the visual-evoked response. We conclude that the sensitivity of the central nervous system to midazolam, as reflected in alpha activity, possibly shows a circadian variation.  相似文献   
166.
From September 1992 to January 1994, we evaluated the use of the CEPRATE SC stem cell concentrator (CellPro, Inc, Bothell, WA) to select CD34+ cells from the bone marrow (BM) of 25 patients with non-Hodgkin's lymphoma in complete remission. This system uses the biotinylated 12.8 IgM MoAb to select CD34+ cells. Cells are retained on an avidin column and detached by agitation. Fifteen patients have been transplanted with the CD34+ purified fraction. The CD34+ purified fraction of the 25 processed BMs contained a median of 0.54% of the original nucleated cells in a volume of 5 to 10 mL. The median concentration of CD34+ cells was 49% (range, 12% to 80%), and the median enrichment of CD34+ cells was 33-fold (range, 9- to 85-fold). This selected CD34+ fraction retained 60% (range, 15% to 95%) of late granulocyte-macrophage colony- forming units (CFU-GM), 55% (range, 12% to 99%) of early CFU-GM, and 31% (range, 2% to 100%) erythroid burst-forming units (BFU-E) corresponding to median enrichments of 22-fold (range, 1- to 71-fold), 19-fold (range, 2- to 58-fold), and 14-fold (range, 2- to 200-fold), respectively. There was a correlation between immune phenotypes and progenitor cells. In the initial buffy-coat fractions, the percentage of CD34+ cells was correlated to the cloning efficiency of both late CFU-GM (P < .05) and early CFU-GM (P < .001). In the final selected fraction, there was a correlation between the percentage of CD34+/CD33- and the cloning efficiency of early CFU-GM (P < .05) and between the percentage of CD34+/CD33+ and the cloning efficiency of late CFU-GM (P < .05). Lymphoma cells positive for t(14; 18) were found by polymerase chain reaction in 9 of 14 buffy coats tested before CD34+ cell purification. In 8 cases, the CD34(+)-selected fraction was found to be negative, and the CD34- fraction was found to be positive. After cryopreservation, the recoveries of progenitor cells in the CD34(+)- purified fraction were 79% for late CFU-GM, 71% for early CFU-GM, and 73% for BFU-E. The 15 patients transplanted with the concentrated CD34+ fraction received a median dose of 1 x 10(6) CD34+ cells/kg (range, 0.3 to 2.96) and 10.62 x 10(4) early CFU-GM/kg (range, 0.92 to 25.55). Median days to recovery to 0.5 x 10(9)/L neutrophils and 50 x 10(9)/L platelets were days 15 (range, 10 to 33) and 23 (range, 11 to 68), respectively.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
167.
168.
Douay  L; Hu  C; Giarratana  MC; Bouchet  S; Conlon  J; Capizzi  RL; Gorin  NC 《Blood》1995,86(7):2849-2855
One of the principal challenges of cancer chemotherapy is the relative inability of most anticancer drugs to distinguish between normal and neoplastic tissues. Consequently, a broad range of toxicities are experienced by patients, especially myelosuppression. Amifostine, a phosphorylated aminothiol, increases the selectivity of specific anticancer drugs for neoplastic cells by protecting normal tissues. One potential application of this protector is during bone marrow purging to selectively remove contaminating cancer cells. This study took normal or leukemic marrow from human subjects and evaluated the ability of amifostine to selectively protect normal bone marrow progenitor cells versus leukemic progenitor cells from the cytotoxic effect of mafosfamide. The dose response of mafosfamide amifostine on leukemia colony-forming units or normal marrow progenitor cells was determined and the LD95 was calculated. Amifostine pretreatment resulted in a statistically significant protection of granulocyte-macrophage colony- forming units and erythroid blast-forming units from the toxicity of mafosfamide (P = .031). Thus, amifostine protection of normal marrow progenitor cells allows a higher LD95 concentration of mafosfamide to be used in ex vivo purging. In contrast, amifostine pretreatment increased the cytotoxicity of mafosfamide on the fresh human leukemia progenitor cells (P = .006). The dual effect of amifostine protection of normal marrow progenitor cells coupled with amifostine-induced sensitization of the leukemia cells increases the possible cell-kill of leukemic stem cells. With amifostine pretreatment, at the LD95 concentrations of mafosfamide for marrow progenitor cells, there was an estimated 6 log increase in cell-kill of the leukemia cells. This selective cell-kill offers the potential for lowering the incidence of leukemic relapse, while preserving more normal stem cells for autologous transplantation.  相似文献   
169.
170.
26 consecutive patients (37 hips) with avascular necrosis (AVN) of the femoral head treated surgically at our institution from 1999 to 2008 were reviewed. The aims of the study were to evaluate the risk factors associated with AVN in HIV positive and HIV negative individuals, and assess early response to total hip replacement (THR) surgery in HIV positive and negative patients. There were 15 male and 11 female patients in total. The mean age for all patients was 47.1± 8.0 years (range, 33 to 66 years). 12 patients were HIV positive, 11 patients were HIV negative and 3 patients had unknown HIV status. Excessive alcohol intake was the most common risk factor for developing AVN .15 patients (58%) had more than one risk factor for AVN and only 2/12 (17%) HIV positive patients had no other risk factor apart from HIV infection. There were no early postoperative complications in 34 arthroplasties in both HIV positive and negative patients. The aetiology of AVN seems often to be multifactorial, even in the presence of HIV infection. Early response to arthroplasty surgery in AVN of the femoral head is equally good irrespective of the HIV serostatus of the patients.  相似文献   
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