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691.
692.
Problem: Longitudinal patient contacts are being implemented worldwide as a way to enhance a patient-centered orientation among medical students. In large medical schools, longitudinal integrated clerkships may not be feasible, so other ways must be sought to expose students to prolonged contact with patients. Intervention: Medical students were attached to a family practice and assigned a panel of 4 patients to follow over the 3 years of their clinical training. Their role was that of companion on the patient’s medical journey. The program consisted of several encounters, joining the patient in the medical setting for significant events, and written assignments. This intervention was piloted with 35 students. We describe our experiences from the 1st pilot year of this program. Context: The intervention was performed with 3rd-year students—of a 6-year curriculum—at a large medical school in the Netherlands. Outcome: Finding enough patients per practice was feasible. On the whole, students fulfilled the program’s expectations regarding frequency of patient encounters and assignments. The most frequent problems encountered by the students were uncertainty about their role and setting boundaries in their contact with the patients. They needed more preceptor supervision and coaching than they received. Lessons Learned: For junior students, close and structured supervision led by the faculty is necessary to help them navigate and learn from a panel of patients. Students need guidance about what role they should take on and on how to manage both their own and their patient’s expectations. Guided reflection is necessary to help students give meaning to their experiences with patients.  相似文献   
693.
We studied 253 children aged <15 years. Phase 1 included 193 children with migraine (1.1 and 1.2) divided into two groups (<10 and ≥ 10 years). We studied the relationship between age and migraine type, headache characteristics, and associated symptoms of the International Headache Society (IHS) definition. A higher frequency of migraine with aura, pulsatile quality, and unilateral location was observed in older children. In phase 2 we studied 176 children with headache (excluding migraine with aura), comparing diagnostic criteria, definition items, sensitivity, and specificity. The results showed that item B of the definition was the most frequent cause of exclusion in the 1.7 diagnostic group. Compared with Vahlquist and the IHS, the Prensky criteria were the most sensitive. Sensitivity was >70% for pain of moderate/severe intensity, duration between 2 and 48 h, isolated photophobia, isolated phonophobia, and aggravation with physical activity. Specificity was >70%, for nausea, vomiting, phonophobia and photophobia, isolated photophobia, aggravation with physical activity, and isolated phonophobia. Based on three alternative definitions, each modifying one item of the IHS definition, the sensitivity and specificity of these alternative definitions were compared with the "extended" criteria (children with migraine without aura and migrainous disturbance, according to the IHS criteria, grouped together). Exclusion of headache duration increased sensitivity by 10%, compared to restrictive IHS criteria, without decreasing specificity.  相似文献   
694.
目的:观察普伐他汀、阿司匹林联用对家兔颈动脉血管成形术后内膜增殖进展的影响及其作用机制。方法:实验于2002-03/12在北京中医药大学教育部中医内科学重点学科实验室完成。雄性日本大耳白兔30只,体质量1.8~2.0kg,动物适应性喂养1周后随机数字表法分为正常对照组(n=9)、假手术组(n=6)、模型组(n=9)、治疗组(n=6)。模型组和治疗组动物氯胺酮、速眠新混合肌注麻醉,沿气管正中切开皮肤,剥离颈总动脉,给予电刺激。术后第2天开始饲喂高脂饲料(胆固醇:0.7%,猪油:3%,普通饲料96.3%);正常对照组无任何干预措施;假手术组仅剥离颈总动脉,不做电刺激,喂高脂饲料;动物连续喂养8周后超声评价颈总动脉,根据B超选择颈总动脉有斑块或血流明显改变者作颈总动脉球囊扩张术。正常对照组、模型组、假手术组喂普通饲料,治疗组喂普伐他汀与阿司匹林含药饲料(普伐他汀5.046mg/kg,阿司匹林2.268g/kg),4周后测血脂和C-反应蛋白浓度、血清一氧化氮及转化生长因子β水平,观察颈动脉组织病理形态学改变,半定量分析增生内膜中胶原含量的变化,免疫组织化学方法分析增生内膜中巨噬细胞和平滑肌细胞阳性百分率。结果:纳入大耳白兔30只,正常对照组中途死亡1只,死因为牙齿畸型影响进食;模型组1只因电刺激8周时超声评价颈动脉未形成斑块及血流无明显改变而剔出实验,进入分析28只。与模型组比,普伐他汀与阿司匹林联用4周后,治疗组胆固醇及三酰甘油水平明显下降[(4.12±2.30),(0.74±0.17)mmol/L;(0.47±0.27),(0.39±0.14)mmol/L;P<0.05],血清C-反应蛋白水平和转化生长因子β水平均降低[(0.86±0.27),(0.57±0.30)mg/L;(3.45±0.77),(3.23±0.34)ng/L;P<0.05],一氧化氮水平升高[(41.79±35.78),(90.14±32.54)mmol/L;P<0.05],动脉内膜增殖程度明显减轻,管腔狭窄率降低,内中膜厚度及内中膜面积比降低[(71.91±14.90)%,(47.20±18.74)%;(0.41±0.17),(0.26±0.04)mm;1.66±0.63,0.78±0.34;P均<0.05],动脉内膜胶原含量减少(30.92±10.05,21.93±5.81,P<0.01),动脉内膜巨噬细胞阳性百分率降低[(13.94±4.91)%,(7.29±7.28)%,P<0.05],平滑肌细胞含量无明显差异(38.37±5.67,35.79±10.68,P>0.05)。结论:普伐他汀与阿司匹林联用具有抑制内膜增生和减少新生内膜胶原含量的作用,其机制与两药抑制炎症反应、保护内皮功能及抑制细胞外基质生成等有关。  相似文献   
695.
目的:利用巢式逆转录-聚合酶链反应扩增的方法,从肌肉组织中扩增人骨形成蛋白2全长cDNA并构建真核表达载体系统。方法:实验于2003-10/2005-10在苏州大学基因工程教研室和北京大学第三医院骨科实验室完成。提取成人肌肉组织内的总RNA,设计内外两对引物以巢式逆转录-聚合酶链反应扩增方法分两次扩增出人骨形成蛋白2全长1188bp基因,经T-A克隆装入pUCM-T质粒载体内,测序验证后,将克隆质粒以Hind Ⅲ和Xba Ⅰ双酶切后与pcDNA3.0载体相连接,构建真核表达载体系统。结果:利用巢式逆转录-聚合酶链反应扩增方法能从成人肌肉组织内扩增出1188bp的人骨形成蛋白2全长cDNA基因,其测序结果显示与Genebank报道序列完全相符。将扩增序列双酶切后与pcDNA3.0载体相连接,经电泳验证,能构建人骨形成蛋白2全长基因的真核表达系统。结论:巢式逆转录-聚合酶链反应扩增方法能从成人肌肉组织内扩增出人骨形成蛋白2全长cDNA基因,并克隆构建真核表达载体系统,为下一步基因组织工程人工骨实验奠定基础。  相似文献   
696.
目的:探讨退行性变腰椎间盘MRI信号强度和髓核蛋白多糖含量之间的相关性,评价MRI在椎间盘生化状态评估中的价值。方法:①对象:随机选择的腰椎间盘髓核样本,取自2006-08/2007-01在山东省千佛山医院手术的33例患有腰椎间盘突出症的患者,患者对实验均知情同意。②方法:术前测量腰椎间盘正中矢状面MRIT2WI信号值;术后用紫外分光光度法测量髓核蛋白多糖的含量。③评估指标:对照研究依据Minnatertti法分为Ⅱ类、Ⅲ类腰椎间盘的MRIT2WI信号强度及髓核蛋白多糖含量,并用Pearson相关检验评估两者之间的相关性。结果:Ⅲ类腰椎间盘正中矢状位T2WI信号强度和髓核蛋白多糖含量明显低于Ⅱ类椎间盘(P<0.001),MRIT2WI信号值和髓核蛋白多糖含量之间的相关系数分别为0.674,0.658(P<0.001)。结论:腰椎间盘MRIT2WI信号强度随髓核蛋白多糖含量的减少而降低,二者之间有明显的相关性。MRI是评价椎间盘生化状态的良好工具。  相似文献   
697.
698.
自身免疫性肝炎患者自身抗体的测定及意义   总被引:2,自引:1,他引:2  
目的:探讨自身抗体测定对诊断自身免疫性肝炎的临床意义.方法:采用间接免疫荧光法(IIF)检测47例自身免疫性肝炎患者、158例非自身免疫性肝炎患者及40例健康体检者体内抗核抗体(ANA)、抗平滑肌抗体(SMA)、抗中性粒细胞胞质抗体(ANCA)、抗线粒体抗体(AMA)等自身抗体,ELISA法检测抗MPO抗体,并对结果进行回顾性分析.结果:ANA、SMA及ANCA检出率的比较,结果显示AIH中阳性率最高为SMA(66.0%, 31/47),而非AIH中则为6.3%(10/158),两组差异有非常显著性意义(P<0.01).经X2检验, SMA、AMA和MPO抗体检测在AIH与PBC中,均有非常显著性意义(P<0.01).AIH各型自身抗体检测结果表明,AIH-Ⅰ与ANA、SMA和ANCA相关,AIH-Ⅱ与LKM相关,而AIH=Ⅲ与SLA和ANCA相关.结论:血清自身抗体的检测对诊断、治疗和阻止自身免疫性肝炎的发展有着十分重要作用,对提高AIH在临床上同其他肝病鉴别诊断和治疗有着非常重要的意义.  相似文献   
699.
The human granulocyte-colony stimulating factor gene (G-CSF) is localized at 17q11.2-q21, the region of one of the breakpoints in the 15;17 chromosome translocation specific for acute promyelocytic leukemia (APL). As G-CSF induces differentiation and loss of tumorigenicity in myeloid leukemic cells or cell lines, it was possible that the translocation in APL involved the DNA of the G-CSF coding region or its regulatory region. In situ hybridization to chromosomes with the t(15;17) from patients with the APL translocation using a G- CSF cDNA clone revealed that the coding region of this gene is proximal to the t(15;17) breakpoint on chromosome 17. Southern analysis of DNA from patients with the APL translocation showed no differences in hybridization between normal and leukemic cells. These results indicate that the G-CSF coding sequence is not disrupted by the chromosomal rearrangement characteristic of APL.  相似文献   
700.
Wang  LM; Michieli  P; Lie  WR; Liu  F; Lee  CC; Minty  A; Sun  XJ; Levine  A; White  MF; Pierce  JH 《Blood》1995,86(11):4218-4227
Interleukin-13 (IL-13) induced a potent mitogenic response in IL-3- dependent TF-1 cells and DNA synthesis to a lesser extent in MO7E and FDC-P1 cells. IL-13 stimulation of these lines, like IL-4 and insulin- like growth factor-1 (IGF-1), resulted in tyrosine phosphorylation of a 170-kD substrate. The tyrosine-phosphorylated 170-kD substrate strongly associated with the 85-kD subunit of phosphoinositol-3 (PI-3) kinase and with Grb-2. Anti-4PS serum readily detected the 170-kD substrate in lysates from both TF-1 and FDC-P1 cells stimulated with IL-13 or IL-4. These data provide evidence that IL-13 induces tyrosine phosphorylation of the 4PS substrate, providing an essential interface between the IL- 13 receptor and signaling molecules containing SH2 domains. IL-13 and IL-4 stimulation of murine L cell fibroblasts, which endogenously express the IL-4 receptor (IL-4R alpha) and lack expression of the IL-2 receptor gamma subunit (IL-2R gamma), resulted in tyrosine phosphorylation of insulin receptor substrate-1 (IRS-1)/4PS. Enhanced tyrosine phosphorylation of IRS-1/4PS was observed in response to IL-4, but not IL-13 treatment of L cells transfected with the IL-2R gamma chain. These results indicate that IL-13 does not use the IL-2R gamma subunit in its receptor complex and that expression of IL-2R gamma enhances, but is not absolutely required for mediating IL-4-induced tyrosine phosphorylation of IRS-1/4PS.  相似文献   
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