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51.
A nationwide study of intracellular drug metabolite concentrations in children prescribed 6-mercaptopurine for the treatment of lymphoblastic leukaemia was carried out to assess interpatient variability at a standardised dose. Nine children (2% of the total) had completely undetectable metabolites, indicative of non-compliance. Five were adolescents, but otherwise they had no obvious distinguishing characteristics. Not taking any 6-mercaptopurine at all is uncommon, but the problem cannot be predicted. The total number of children who do not comply cannot be determined from this study, but the nine children described represent only a fraction of these. 相似文献
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Zhao P Cao J Zhao LJ Qin ZL Ke JS Pan W Ren H Yu JG Qi ZT 《第二军医大学学报》2006,27(5):506-506
The nucleocapsid (N) protein of SARS-coronavirus (SARS-CoV) is the key protein for the formation of the helical nucleocapsid during virion assembly. This protein is believed to be more conserved than other proteins of the virus, such as spike and membrane glycoprotein. In this study, the N protein of SARS-CoV was expressed in Escherichia coli DHSalpha and identified with pooled sera from patients in the convalescence phase of SARS. A plasmid pCI-N, encoding the full-length N gene of SARS-CoV, was constructed. Expression of the N protein was observed in COS1 cells following transfection with pCI-N. The immune responses induced by intramuscular immunization with pCI-N were evaluated in a murine model. Serum anti-N immunoglobutins and splenocytes proliferative responses against N protein were observed in immunized BALB/c mice. The major immunoglobulin G subclass recognizing N protein was immunoglobulin G2a, and stimulated splenocytes secreted high levels of gamma interferon and IL-2 in response to N protein. More importantly, the immunized mice produced strong delayed-type hypersensitivity (DTH) and CD^8+ CTL responses to N protein. 相似文献
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Diffusion-Weighted Magnetic Resonance Imaging as a Cancer Biomarker: Consensus and Recommendations 总被引:3,自引:0,他引:3 下载免费PDF全文
Anwar R Padhani Guoying Liu Dow Mu-Koh Thomas L Chenevert Harriet C Thoeny Taro Takahara Andrew Dzik-Jurasz Brian D Ross Marc Van Cauteren David Collins Dima A Hammoud Gordon JS Rustin Bachir Taouli Peter L Choyke 《Neoplasia (New York, N.Y.)》2009,11(2):102-125
On May 3, 2008, a National Cancer Institute (NCI)-sponsored open consensus conference was held in Toronto, Ontario, Canada, during the 2008 International Society for Magnetic Resonance in Medicine Meeting. Approximately 100 experts and stakeholders summarized the current understanding of diffusion-weighted magnetic resonance imaging (DW-MRI) and reached consensus on the use of DW-MRI as a cancer imaging biomarker. DW-MRI should be tested as an imaging biomarker in the context of well-defined clinical trials, by adding DW-MRI to existing NCI-sponsored trials, particularly those with tissue sampling or survival indicators. Where possible, DW-MRI measurements should be compared with histologic indices including cellularity and tissue response. There is a need for tissue equivalent diffusivity phantoms; meanwhile, simple fluid-filled phantoms should be used. Monoexponential assessments of apparent diffusion coefficient values should use two b values (> 100 and between 500 and 1000 mm2/sec depending on the application). Free breathing with multiple acquisitions is superior to complex gating techniques. Baseline patient reproducibility studies should be part of study designs. Both region of interest and histogram analysis of apparent diffusion coefficient measurements should be obtained. Standards for measurement, analysis, and display are needed. Annotated data from validation studies (along with outcome measures) should be made publicly available. Magnetic resonance imaging vendors should be engaged in this process. The NCI should establish a task force of experts (physicists, radiologists, and oncologists) to plan, organize technical aspects, and conduct pilot trials. The American College of Radiology Imaging Network infrastructure may be suitable for these purposes. There is an extraordinary opportunity for DW-MRI to evolve into a clinically valuable imaging tool, potentially important for drug development. 相似文献
54.
千层塔中三萜成分的研究 总被引:5,自引:0,他引:5
前曾报道自千层塔[Huperzia serrata Thunb.(Trev)=Lycopodium serratum Thunb(Trev.)]中分得具有胆碱酯酶抑制活性的新生物碱——石杉碱甲、石杉碱乙、甲基石杉碱乙及已知生物碱8-deoxyserratinine,serratinine,lycodoline及lycoclavine。为进一步阐明该植物的化学成分,我们对其三萜成分进行了研究。从浙江安吉产的千层塔植物中分到六个石松三萜,其中一个为新化合物,经下述方法推定为serratenediol-21-acetate(Ⅰ)。另五 相似文献
55.
本文报道我国西南产麻黄——丽江麻黄Ephedra likiangensis Florin、匍枝丽江麻黄E.likiangensis f.mairei(Florin)C.Y.Cheng、藏麻黄E.saxatilis Royle ex Florin、山岭麻黄E.gerardiana Wall、垫状山岭麻黄E.gerardiana Var.congesta C.Y.Cheng、矮麻黄E.minuta Florin和异株矮麻黄E.minuta var.dioeca C.Y.Cheng,以及形态组织特征较特殊的宁夏产斑子麻黄E.lepidosperma C.Y.Cheng、新疆产窄膜麻黄E.lomatolepis Schrenk,西藏产西藏中麻黄E.intermedia var.tibetica Stapf的生药形态组织学研究结果。并根据对国产麻黄的生药形态组织学的系统研究结果,分别编写了各种国产麻黄(包括13种3变种1变型)的生药性状和生药显微特征检索表。 相似文献
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Erin C. Strumpf Nichole Austin Ariella Lang Shelley Derksen James Bolton Marni Brownell Patricia Gregory Dan Chateau Maureen Heaman 《Health services research》2022,57(4):786
ObjectiveTo evaluate the effects of early pregnancy loss on subsequent health care use and costs.Data SourcesLinked administrative health databases from Manitoba, Canada.Study DesignThis was a population‐based cohort study. The exposure of interest was first recorded ectopic pregnancy or miscarriage (EPM). Outcomes included visits to all ambulatory care providers, family physicians (FPs), specialists, and hospitals, as well as the costs associated with these visits. We also assessed the impact of EPM on a global measure of health service utilization and the incidence and costs of psychotropic medications.Data Collection/Extraction MethodsWe identified women who experienced their first recorded loss (EPM) from 2003–2012 and created a propensity score model to match these women to women who experienced a live birth, with outcome measures available through 31 December 2014. We used a difference in differences approach with multivariable negative binomial models and generalized estimating equations (GEE) to assess the impact of EPM on the aforementioned health care utilization indicators.Principal FindingsEPM was associated with a short‐term increase in visits to, and costs associated with, certain ambulatory care providers. These findings were driven in large part by increased visits/costs to FPs (rate difference [RD]: $19.92 [95% CI: $16.33, $23.51]) and obstetrician‐gynecologists (OB‐GYNs) (RD $9.41 [95% CI: $8.42, $10.40]) in the year immediately following the loss, excluding care associated with the loss itself. We also detected an increase in hospital stays and costs and a decrease in the use of psychotropic medications relative to matched controls.ConclusionPregnancy loss may lead to subsequent increases in certain types of health care utilization. While the absolute costs associated with post‐EPM care are relatively small, the observed patterns of service utilization are informative for providers and policy makers seeking to support women following a loss. 相似文献
60.
目的:通过使用CT三维测量髋臼发育情况及髋臼对股骨头覆盖率对比性观察,整体反映髋臼发育情况。方法:①观察对象:选择2003-06/2005-04对41例发育性髋关节脱位患者55个髋关节。其中男12例,女29例;年龄18个月~6岁。患髋右侧23例,左侧32例,其中双侧12例。健康侧27髋。患儿家属均知情同意。②实验方法:所有患儿使用PQ6000型多层螺旋CT扫描,扫描数据进行骨组织三维重建。将测量数据制成图表,显示三维的髋臼发育情况,并量化表示髋臼的缺损情况。③实验评估:计算不同截面正常侧髋臼指数、中心边缘角(假设符合正态分布)的均数、标准差、分布范围及95%可信区间。观察发育性髋关节脱位术前术后骨骼形态学变化。分别在术前、术后测量患者患侧髋臼指数、中心边缘角和前倾角,测量值均分别与正常值进行对比。结果:患侧55个髋,健康侧27髋,均进入结果分析。①发育性髋关节脱位术前术后骨骼形态学变化:术前55侧发育性髋关节脱位髋关节脱位程度为,参照T"nnis分类方法,Ⅰ度5髋(9.1%),Ⅱ度11髋(20%),Ⅲ度32髋(58.2%),Ⅳ度7髋(12.7%)。术后患者均表现髋臼α角均>90°,头臼呈同心圆对位,Shenton线连续,股骨头较术前明显发育,原先未出现头骺的患者,出现头骺,但较正常仍偏小;髋臼口呈类圆形,髋臼边缘欠光滑,髋臼整体呈一定程度前倾。②术前术后髋臼指数、中心边缘角和前倾角变化对比:术后患者的髋臼指数和前倾角与正常对照组之间差异无显著性(P>0.05),术后患者的中心边缘角大于正常对照组[(33.4±2.6)°(29.1±2.0)°,P<0.01],术后患者的髋臼指数和前倾角测量值均小于术前(P<0.01)。结论:介绍了一种对髋臼形态测量的新方法,它能够全面反映髋臼的发育情况,不但增加了对中心边缘髋臼病理改变的认识程度,还为手术提供了精确的可信度较高的矫形设计方案。 相似文献