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121.
Context Residents in all disciplines serve as clinical teachers for medical students. Since the 1970s, there has been increasing evidence to demonstrate that residents wish to teach and that they respond positively to formal teacher training. Effective resident‐as‐teacher (RaT) programmes have resulted in improved resident teaching skills. Current evidence, however, is not clear about the specific features of an effective RaT programme. Objectives This study was performed in order to investigate the effectiveness of RaT programmes on resident teaching abilities and to identify the features that ensure success. Methods of assessment used to ascertain the effectiveness of RaT programmes are also explored. Methods The literature search covered the period between 1971 and 2008. Articles focusing on improving resident teaching skills were included. Each study was reviewed by two reviewers and data were collected using a standard abstraction summary sheet. Study outcomes were graded according to a modified Kirkpatrick's model of educational outcomes. Results Twenty‐nine studies met review inclusion criteria. Interventions included workshops, seminars, lectures and teaching retreats. Twenty‐six studies used a pre‐ and post‐intervention outcome comparison method. Subjective outcome measures included resident self‐evaluation of teaching skills or evaluation by medical students, peers and faculty members. Objective outcome measures included written tests, evaluation of teaching performance by independent raters and utilisation of objective structured teaching examinations. One study objectively measured learning outcomes at the level of medical students, utilising the results of an objective structured clinical examination. Overall resident satisfaction with RaT programmes was high. Participants reported positive changes in attitudes towards teaching. Participant knowledge of educational principles improved. Study methodologies allowed for significant risks of bias. Conclusions More rigorous study designs and the use of objective outcome measures are needed to ascertain the true effectiveness of RaT programmes. Future research should focus on determining the impact of RaT programmes on learning achievement at the level of medical students. 相似文献
122.
翼腭窝的CT三维成像 总被引:2,自引:0,他引:2
目的:探讨CT三维成像评价翼腭窝解剖结构的价值。材料和方法:使用Philips Mx8000型多层CT检查仪对5个成人头颅标本进行准直1mm或0.5mm的容积采集,并将数据输入配套Mxview工作站(SGI02)进行三维重建处理,包括容积显示(VR)和三维正交多平面重建(MPR)。鼻腔内侧壁相关结构进行测量并与标本测量进行对比。结果:CT三维正交多平面重建图像可以十分清楚地显示翼腭窝结构及其6个通路结构,VR可以清楚、准确地显示鼻腔内侧壁结构,并均可以获得准确测量。结论:CT容积采集结合合理的三维重建可以直观、立体地显示翼腭窝解剖及其相关通连结构。 相似文献
123.
Yih-Sharng Chen Hsi-Yu Yu 《European journal of cardio-thoracic surgery》2005,27(5):931-2; author reply 932
124.
125.
目的:研究安氏II类错畸形对青春期面部骨轮廓发育的影响。方法:收集安氏II类错畸形的成人患者和青少年患者共362例。摄取头颅定位侧位片及头颅定位正位片。对面高、面宽等19项测量项目做比较分析及t检验。结果:①安氏II类青少年患者与正常青少年相比,下颌基骨长度、下颌长度较小,但无统计学差异。②安氏II类成年患者与正常成年人相比,下颌基骨长度、下颌长度有显著性差异。③安氏II类患者下颌骨在青春发育期有向前、向上旋转的趋势。结论:安氏II类错畸形患者经过青春期发育,使面部畸形程度更加严重。本研究得出安氏II类错畸形对青春期面部骨轮廓发育的影响,对正颌外科和正畸治疗具有参考意义。 相似文献
126.
C K H Yu A T Papageorghiou R Bindra K Spencer K H Nicolaides 《The journal of maternal-fetal & neonatal medicine》2004,16(3):158-162
OBJECTIVE: To investigate whether maternal plasma sex hormone-binding globulin (SHBG) concentrations are reduced in women who subsequently develop pre-eclampsia. METHODS: This was a cross-sectional study, carried out at antenatal clinics in seven hospitals in and around London. Healthy women underwent uterine artery Doppler velocimetry as a screening method for pre-eclampsia at 22-24 weeks of gestation. The first group (408 women) had normal uterine artery Doppler waveforms (mean uterine artery pulsatility index (PI) below 1.6). The second group (274 women) had increased impedance to flow in the uterine arteries (mean PI above the 95th centile, 1.6). Maternal plasma SHBG concentrations were measured retrospectively using a competitive chemiluminescent immunoassay. Pre-eclampsia was as defined by the International Society for the Study of Hypertension in Pregnancy. RESULTS: Plasma SHBG concentrations in the 80 (11.7%) women who subsequently developed pre-eclampsia were significantly lower than in the 585 (85.8%) women with normal pregnancy outcomes (median 336, range 142-674 nmol/l vs. median 336, range 142-674 nmol/l, p = 0.001). There was a strong correlation between SHBG concentrations and body mass index (r =-0.232246, p < 0.0001). There were no significant differences in maternal plasma SHBG concentrations in women with abnormal uterine artery Doppler (n = 274) compared with controls (n = 408) (median 324, range 101-635 nmol/l vs. median 336, range 142-674 nmol/l, p = 0.09). CONCLUSION: Maternal plasma SHBG concentrations are reduced in women who subsequently develop pre-eclampsia. 相似文献
127.
目的探讨乳腺癌术后胸部气压固定带的制作及临床应用价值。方法将64例乳腺癌术后患者随机分为观察组和对照组各32例,对照组采用传统的绷带加压包扎,观察组采用自行设计并制作的胸部气压固定带加压包扎。观察两组术后引流量、拔管时间及并发症的发生情况。结果观察组皮下积液发生率显著低于对照组(P〈0.05),术后24h引流量、置管时间显著少于/短于对照组(均P〈0.01)。结论乳腺癌术后使用胸部气压固定带加压固定可减少渗出,缩短置管时间,降低皮下积液发生率。 相似文献
128.
Padmaja Yalamanchili Eric Wexler Megan Hayes Ming Yu Jody Bozek Mikhail Kagan Heike S. Radeke Michael Azure Ajay Purohit David S. Casebier Simon P. Robinson 《Journal of nuclear cardiology》2007,14(6):782-788
Background
BMS-747158-02 is a novel fluorine 18-labeled pyridazinone derivative designed for cardiac imaging. The uptake and retention
mechanisms of F-18 BMS-747158-02 in cardiac myocytes were studied in vitro, and the biodistribution of F-18 BMS-747158-02
was studied in vivo in mice.
Methods and Results
Fluorine 19 BMS-747158-01 inhibited mitochondrial complex I (MC-I) in bovine heart submitochondrial particles with an IC50 of 16.6±3 nmol/L that was comparable to the reference inhibitors of MC-1, rotenone, pyridaben, and deguelin (IC50 of 18.2±6.7 nmol/L, 19.8±2.6 nmol/L, and 23.1±1.5 nmol/L, respectively). F-18 BMS-747158-02 had high uptake in monolayers
of neonatal rat cardiomyocytes (10.3%±0.7% of incubated drug at 60 minutes) that was inhibited by 200 nmol/L of rotenone (91%±2%)
and deguelin (89%±3%). In contrast, an inactive pyridaben analog, P-0 (IC50 value>4 μmol/L in MC-1 assay), did not inhibit the binding of F-18 BMS-747158-02 in cardiomyocytes. Uptake and washout kinetics
for F-18 BMS-747158-02 in rat cardiomyocytes indicated that the time to half-maximal (t1/2) uptake was very rapid (approximately 35 seconds), and washout t1/2 for efflux of F-18 BMS-747158-02 was greater than 120 minutes. In vivo biodistribution studies in mice showed that F-18 BMS-747158-02
had substatial myocardial uptake (9.5%±0.5% of injected dose per gram) at 60 minutes and heart-to-lung and heart-to-liver
ratios of 14.1±2.5 and 8.3±0.5, respectively. Positron emission tomography imaging in the mouse allowed clear cardiac visualization
and demonstrated sustained myocardial uptake through 55 minutes.
Conclusions
F-18 BMS-747158-02 is a novel positron emission tomography cardiac tracer targeting MC-I in cardiomyocytes with rapid uptake
and slow washout. These characteristics allow fast and sustained accumulation in the heart. 相似文献
129.
Seong-Beom Koh Byung-Jo Kim Moon Ho Park Sung-Wook Yu Kun-Woo Park Dae Hie Lee 《Journal of clinical neuroscience》2007,14(11):1073-1077
Cerebral infarction as a complication of tubercular (TB) meningitis is not uncommon, but an adequate comparison of patients with and without stroke has not been carried out. This study was performed to evaluate the clinical characteristics of cerebral infarction secondary to TB meningitis, and to investigate predictive factors for cerebral infarction in patients with TB meningitis. Patients with TB meningitis were recruited over a period of 56 months. They were divided into two groups, those with and those without stroke. Demographic features and clinical, laboratory, and neuroradiological findings were compared between the two groups. We classified strokes into subtypes using neuroimaging findings. Of the 38 patients who were diagnosed with TB meningitis, eight also experienced cerebral infarction. The percentage of cerebrospinal fluid leukocytes that were neutrophils was significantly higher in patients with stroke (68%) than in patients without stroke (31%; p=0.0001). Upon initial CT imaging, meningeal enhancement was found in 11 patients, and of these patients, six experienced stroke. There were no significant differences between the groups with respect to other clinical and laboratory features, including demographic features, time between meningitis onset and treatment initiation, peripheral white blood cell count, and cerebrospinal fluid findings. Five of the eight patients who developed stroke had lacunar infarcts. One of the three patients with territorial nonlacunar infarction died due to herniation. When treating patients with TB meningitis, the possibility of cerebral infarction should be considered when patients develop focal neurological signs, meningeal enhancement on a CT scan, and sustained polymorphic cerebrospinal fluid pleocytosis. 相似文献
130.
目的探讨定量测定肝癌患者血清12种肿瘤标志物的临床意义。方法用蛋白芯片技术定量测定42例正常人、46例肝癌、41例肝炎和23例肝硬化患者血清12种肿瘤标志物的变化并对检测效果进行评价。结果42例正常人CA-199(KU/L)、NSE(g/L)、CEA(g/L)、CA-242(KU/L)、Ferritin(g/L)、β-HCG(g/L)、AFP(g/L)、f-PSA(g/L)、PSA(g/L)、CA-125(KU/L)、HGH(g/L)和CA-153(KU/L)的含量分别为12.42±10.62、2.22±1.43、1.28±1.20、5.72±5.73、91.17±79.43、0.64±0.34、2.96±3.93、0.13±0.11、0.61±1.40、5.46±9.65、1.61±2.40、9.83±9.51;46例肝癌患者血清12种肿瘤标志物含量依次为:35.09±39.50、2.83±4.13、2.98±8.72、8.47±23.42、157.50±129.77、0.72±0.72、87.58±63.27、0.15±0.19、0.58±1.88、56.34±102.02、3.63±4.57、15.65±51.09;41例肝炎患者其含量依次为:76.23±96.57、4.12±4.94、2.06±3.92、4.68±6.99、298.76±326.82、1.00±0.74、63.16±91.76、0.11±0.006、0.27±0.94、18.57±36.60、3.63±4.00、6.13±6.86;23例肝硬化患者其含量依次为:49.85±75.60、5.47±14.97、1.71±1.77、12.44±34.55、278.32±326.82、0.70±0.54、52.89±98.28、0.22±0.21、2.24±4.36、111.50±191.99、2.15±0.99、10.51±15.79。该蛋白芯片测定的敏感性为50.0%,特异性为64.2%,阳性预测值为37.7%,阴性预测值为74.7%。结论采用蛋白芯片技术同时测定患者血清多种肿瘤标志物,对普查肿瘤和临床疗效观察有较好应用价值。 相似文献