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71.
Antiproliferative Activity Against MCF‐7 Breast Cancer Cells by Diamino‐Triazaspirodiene Antifolates
Xiang Ma Renee Ser‐Peng Woon Paul Chi‐Lui Ho Wai‐Keung Chui 《Chemical biology & drug design》2009,74(3):322-326
Two triazaspirodienes, having similar phenoxy propyloxy side chain, were identified as potent mammalian dihydrofolate reductase inhibitors; one having a 6,5‐spiro bicyclic ring system (IC50 = 2.3 nm ) and the other a 6,6‐spiro bicyclic system (IC50 = 6.9 nm ). They also showed more than 50% antiproliferative activity against the MCF‐7 breast cancer cells at 20 μm . This study demonstrated the potential lead of the diamino‐triazaspirodienes in anticancer chemotherapeutical agents’ discovery. 相似文献
72.
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
73.
目的探讨散发型Creutzfeldt-Jakob病(sCJD)的MR特点。方法回顾性分析3例临床诊断为sCJD的患者资料,MR采用SE T1 WI、快速自旋回波(FSE)T2 WI、扩散加权成像(DWI)扫描,观察其MR表现特征。结果3例SE TI WI和FSE T2 WI序列对基底节区和皮质的病变显示不佳,DWI则可清晰地显示病变,额、顶、枕叶皮质最常受累,表现为高信号,病变可对称,也可不对称,皮层下区脑白质信号未见异常。双侧尾状核、丘脑也可受累,DWI上呈高信号。晚期脑实质广泛萎缩,以皮质为著。结论sCJD采用DWI序列结合其特征性的临床表现可作出较为准确的诊断。 相似文献
74.
75.
Serum IgA and IgG functional antibodies and their subclasses to Streptococcus pneumoniae capsular antigen found in two aged‐matched cohorts of children with and without otitis media with effusion The relationship between acute otitis media and otitis media with effusion (OME) is uncertain and the aetiology of OME is multifactorial. Otitis media with effusion may be an inflammatory condition; both bacteria and viral infections could play a part in this inflammation. The four bacteria Streptococcus pneumoniae, Haemophilus influenza, Staphylococcus aureus and Branhamella catarrhalis cause 60% of the infections whereas S. pneumoniae accounts for up to 35%. IgA provides the dominant surface response to polysaccharide and lipopolysaccharide antigens, of which IgA2 is the main subclass. Once the mucosa has been breached, most protection is provided by IgG. IgG2 acts mainly against bacterial capsular antigens. This study looked at two groups of 50 children with and without OME who were aged between 3 and 10 years. The aims were to determine if, firstly, the levels of the serum immunoglobulins were different in the two groups, secondly whether these children made the appropriate antibody response to the capsular antigen to S. pneumoniae (PCP), and finally if there was a delay in the maturity of the IgA response. The total IgG, IgA and all subclass levels were measured using radial immunodiffusion. Levels of functional IgA and IgG were measured using ELISAs (25 patients in each group). The results were analysed with non‐parametric tests. The immunoglobulin levels were within the normal levels for both groups. There were very good correlations between the IgG total anti‐PCP and the IgG2 anti‐PCP (R > 0.9, p = 0.001). There was a good correlation between the levels of both IgG total and IgG2 anti‐PCP against IgA total anti‐PCP in both groups (R > 0.85, p > 0.01). This confirms a normal antibody response between both groups of patients. The ages of the controls and patients (50 samples) were correlated with increasing titres of circulating functional antibodies (P = 0.001). This is highly suggestive of a normal age‐related response. In conclusion, the findings were contradictory to our original hypothesis that there is a subtle difference in surface protection between children with and without OME. We believe that a previous history of recurrent acute otitis media is unrelated to the development of OME after 3 years of age. 相似文献
76.
77.
This study examined the effects of cognitive-behavioral group therapy (CBT) on the self-esteem, depression, and self-efficacy of runaway adolescents residing in a shelter in Seoul, South Korea. The study used a control group pretest-posttest design. The experimental group and the control group consisted of 14 and 13 male subjects, respectively, with subjects having been randomly assigned to these groups. The experimental group participated in a CBT that consisted of eight sessions over an 8-week period; the control group did not participate in the program. To examine the effects of the CBT on dependent variables, the Wilcoxon signed rank test was used. The scores on depression decreased significantly (z = -2.325, p = .02) and those on self-efficacy increased significantly (z = -2.098, p = .03) after the intervention in the experimental group. There was no significant change on self-esteem (z = -1.19, p = .23). In the control group, the scores on depression, self-esteem, and self-efficacy did not change significantly after the intervention period. The CBT developed in this study consisted of structured and specific content that could be usefully applied to runaway adolescents residing in a shelter. 相似文献
78.
79.
In cases of displaced greater tuberosity fractures, treatments by arthroscopic-assisted reduction and percutaneous screw fixation have been reported. However, in cases in which there is a comminuted fracture or a minimally displaced fracture combined with concomitant lesions such as rotator cuff tear or labral pathology, it is difficult to reduce the fracture and to treat other pathologies by use of a percutaneous screw. Recently, many surgeons have used the double-row repair method in rotator cuff repair, which provides a tendon-bone interface better suited for biologic healing and restoring normal anatomy. In accordance with this method, we used the arthroscopic technique of double-row suture anchor fixation for a minimally displaced greater tuberosity fracture without additional incision. Initially, debridement was performed on the fracture surface by use of a shaver, and the medial-row anchor was inserted through the anterior portal or the intact cuff. Two lateral-row anchors were inserted just anterior and posterior to the lower margin of the fractured fragment under C-arm guidance. The medial-row sutures and lateral-row sutures were then placed. Arthroscopic double-row suture anchor fixation of a displaced greater tuberosity fracture restores the original footprint of the rotator cuff and normal tendon-bone interface of the displaced greater tuberosity fracture. 相似文献
80.