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0 引言 人类免疫缺陷病毒 (human immunodeficiencyvirus,HIV) - 1编码的反式激活蛋白 TAT具有独特的跨膜运转方式 ,而且有转导速度快 ,效率高的特点 ,被称为蛋白转导结构域 (protein transduction domain,PTD) [1 ,2 ] .本研究用PCR扩增了慢性粒细胞白血病慢粒 bcr/ abl融合蛋白的基因片段 ,在其 5′端融合 PTD结构域的编码区后在大肠杆菌中进行了表达 .表达产物经纯化后 ,加入培养的 HL 6 0细胞 ,表达的蛋白可直接进入细胞内 .这一结果为用外源蛋白负载(L oading)免疫细胞提供了新的途径 .1 材料和方法1.1 DNA重组 人工合… 相似文献
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The prevalence of microalbuminuria was assessed in 50 patients of non-insulin dependent diabetes mellitus. The mean age of patients was 52.1 ± 11.6 years and the duration of diabetes was 8.3 ± 6.8 years. Twenty (40%) patients had microalbuminuria. Microalbuminuria was more common in patients with a longer duration of diabetes (more than 5 years), a poor glycaemic control, and higher systolic blood pressure.KEY WORDS: Microalbuminuria, Diabetes mellitus, Diabetic nephropathy, Chronic renal failure 相似文献
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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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Jennifer L. Biggs Jamie S. Sutherell Rochelle Remus Eric S. Armbrecht 《Teaching and learning in medicine》2018,30(2):202-212
Problem: Student–preceptor discontinuity during 3rd-year clerkships limits the quality and quantity of supervision, teaching, and feedback. Although longitudinal integrative clerkships increase continuity and are associated with improved student and preceptor experience, they require schoolwide curricular reform. Alternative innovations enhancing student–preceptor relationships within the constraints of a traditional block clerkship may demonstrate similar benefits. Intervention: We piloted a continuity-enhanced general pediatric ambulatory schedule during 2 consecutive clerkship blocks in 2013. Students in the continuity-enhanced model (n = 29) were assigned 1–3 primary clinic preceptors, whereas those in the traditional model (n = 30) worked with 5–8. Data were gathered from student assessments and anonymous student and preceptor surveys. We used t and Fisher's exact tests to compare the two groups and performed thematic analysis of free-text survey comments. Context: Our school utilizes a block clerkship model with approximately 30 students rotating through the pediatric clerkship every 8 weeks. During the 3-week ambulatory portion, students spend 8 half days in the general pediatric ambulatory clinic. At the conclusion of each clinic, attendings completed brief student evaluation cards. Traditionally, student and attending schedules were created independently, resulting in transient supervisory relationships and dissatisfaction with clinical engagement, feedback, and evaluation. Outcome: Seventy-three percent (43/59) of the students completed the survey. Ten general ambulatory attendings collectively completed 87.5% (35/40) of the monthly surveys. Continuity students received significantly more narrative evaluation comments (10.6 vs. 5.8, p <. 001) from general ambulatory clinic attendings and were more likely to have at least one general ambulatory clinic attending endorse being able to provide meaningful feedback and evaluation (n = 29, 100% vs. n = 20, 66.7%, p <. 001). Continuity students were also more likely to endorse being able to ask at least one of these attendings for a letter of recommendation (71.4% vs. 9.1%, p <. 001) and to have at least one general ambulatory clinic attending endorse being able to provide a meaningful letter of recommendation if asked (62.1% vs. 3.3%, p <. 001). Students (88.4%) and attendings (85.7%) preferred the continuity-enhanced schedule. The most frequent theme of both student and attending free-text survey remarks were relationships and assessment. Lessons Learned: Intentional scheduling of clerkship students to enhance preceptor continuity resulted in significant positive outcomes echoing the relationship-based educational benefits of longitudinal clerkships, particularly in regards to student assessment and feedback. Clerkship directors and other medical educators should consider implementing small changes within block clerkships to maximize student–preceptor continuity. 相似文献
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