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1.
1 建立新型师生关系是实施素质教育的需要
传统教学中,教师是知识的载体,是教学活动的主宰。学生是教师知识传授的对象。课堂上,教师站在讲台上严肃认真地讲解。学生规规矩矩地坐在座位上专心听讲。教师讲的知识点,学生掌握了,就达到教学目的了。教师对学生最为关注的是其学习成绩。学生对教师则敬而远之,甚至关系紧张,很难向教师敞开心扉、畅所欲言。素质教育的核心就是创新教育。而这种师生关系严重阻碍了学生个性的发展和创新意识的培养。 相似文献
2.
Kei Kamide Yoshihiro Kokubo Hironori Hanada Junko Nagura Jin Yang Shin Takiuchi Chihiro Tanaka Mariko Banno Yoshikazu Miwa Masayoshi Yoshii Tetsutaro Matayoshi Hisayo Yasuda Takeshi Horio Akira Okayama Hitonobu Tomoike Yuhei Kawano Toshiyuki Miyata 《Hypertension research》2006,29(4):243-252
Mutations in the gene encoding 11beta-hydroxysteroid dehydrogenase type 2, HSD11B2, cause a rare monogenic juvenile hypertensive syndrome called apparent mineralocorticoid excess (AME). In AME, defective HSD11B2 enzyme activity results in overstimulation of the mineralocorticoid receptor (MR) by cortisol, causing sodium retention, hypokalemia, and salt-dependent hypertension. Here, we have studied whether genetic variations in HDS11B2 are implicated in essential hypertension in Japanese hypertensives and the general population. By sequencing the entire coding region and the promoter region of HDS11B2 in 953 Japanese hypertensives, we identified five missense mutations in 11 patients (L14F, n = 5; R74H, n = 1; R147H, n = 3; T156I, n = 1; R335H, n = 1) and one novel frameshift mutation (4884Gdel, n = 1) in a heterozygous state, in addition to 19 genetic variations. All genetic variations identified were rare, with minor allele frequencies less than 0.005. Four of 12 patients with the missense/frameshift mutations showed renal failure. Four missense mutations, L14F, R74H, R147H, and R335H, were successfully genotyped in the general population, with a sample size of 3,655 individuals (2,175 normotensives and 1,480 hypertensives). Mutations L14F, R74H, R147H, and R335H were identified in hypertensives (n = 6, 8, 3, and 0, respectively) and normotensives (n = 8, 12, 5, and 0, respectively) with a similar frequency, suggesting that these missense mutations may not strongly affect the etiology of essential hypertension. Since the allele frequency of all of the genetic variations identified in this study was rare, an association study was not conducted. Taken together, our results indicate that missense mutations in HSD11B2 do not substantially contribute to essential hypertension in Japanese. 相似文献
3.
4.
Jin Sik Burm 《Journal of plastic, reconstructive & aesthetic surgery》2006,59(3):253-256
This paper describes the use of a composite graft from the mastoid area consisting of full-thickness skin peripherally and selectively localised fascia-fat tissue underneath the skin centrally for immediate reconstruction of moderate defects of the nasal tip including the columella and soft triangle. Mastoid composite grafting is a simple and safe procedure that avoids partial graft loss and provides adequate augmentation of soft tissue, easy reshaping of the new nostril rim, minimal post-operative shrinkage, and no donor-site morbidity. Then, it results in a satisfactory nasal appearance with adequate tip projection and symmetry. This procedure may represent a preferred method of nasal tip reconstruction. 相似文献
5.
Ayad Al Darrab Jerome Fan Christopher M B Fernandes Rosanne Zimmerman Rhonda Smith Andrew Worster Teresa Smith Kelly O'Connor 《European journal of emergency medicine》2006,13(1):32-35
STUDY OBJECTIVES: Use of fast track has been shown to improve the emergency department flow of less urgent patients. It has been speculated, however, that this could negatively affect the care of urgent patients. The objective of this study was to determine whether a dedicated fast track for less urgent patients [Canadian Triage and Acuity scale category 4/5 (CTAS 4/5)] affected (1) the time to assessment for urgent patients (CTAS 3), (2) the length of stay for less urgent patients (CTAS 4 and 5), and (3) the left-without-being-seen rate. METHODS: In June 2003, fast track was opened in our emergency department from 13:00 to 19:00 h. A before-after intervention comparison analysis was completed for 1 week in Aug 2002 and the same week in Aug 2003. Data collected included (1) time to assessment of CTAS 3 patients, (2) the length of stay for CTAS 4/5 patients, and (3) percentage of patients who left without being seen. RESULTS: A total of 368 patients were reviewed for 2002 and 380 patients were reviewed for 2003. Median time to assessment of CTAS 3 patients presenting from 13:00 to 19:00 h was reduced from 66 min (Interquartile range: 40, 94 min) in 2002 to 60 min (IQR: 38, 108 min) after fast track was open in 2003 (P = 0.95). Median length of stay of CTAS 4 and 5 patients was reduced from 170 min (IQR: 111, 256 min) to 110 min (IQR: 69, 185 min) (P < 0.001). The overall left-without-being-seen rate decreased from 5% (20/368) to 2% (9/380). CONCLUSION: A dedicated fast track for CTAS 4/5 patients can reduce the length of stay and the left-without-being-seen rate with no impact on CTAS 3 patients seen in the main emergency department. 相似文献
6.
目的 探讨Lugol液染色对食管早期癌和癌前病变的诊断价值。方法 对45例食管黏膜可疑病变经内镜以2%Lugol液喷洒染色,观察黏膜染色情况,并取活检送病理组织学检查。结果 45例食管病变染色后,39例呈浅染色或不染色,其中食管癌8例(食管早期癌5例,进展期癌3例),Barrett食管5例,轻至中度不典型增生1l例。本组Lugol液染色对食管早期癌和癌前病变的检出率达46.7%。结论 内镜下应用Lugol液染色结合活检有助于食管早期癌和癌前病变的诊断,且操作简便,具有重要的临床价值。 相似文献
7.
Jin Hwan Ahn Joon Ho Wang Jae Chul Yoo Sung Kon Kim Jung Ho Park Jong Woong Park 《Knee surgery, sports traumatology, arthroscopy》2006,14(12):1288-1291
This article describes a modified suture technique designed for the vertical repair of the anterior horn of the meniscus after arthroscopic decompression of a large meniscal cyst. This procedure comprises of three steps: first, the meniscus was pierced vertically using a suture hook and a No. 0 PDS suture. Second, both ends of the No. 0 PDS on the femoral and tibial surfaces of the meniscus were pulled to the outside of the joint capsule using a spinal needle preloaded with suture material. Finally, a skin incision was made adjacent to the suture materials, and both ends were tied. We recommend this technique not only for the vertical repair of the anterior horn of the meniscus after decompression of large meniscal cyst, but also to repair a longitudinal tear of the meniscus. 相似文献
8.
9.
β-胡萝卜素立体异构体对环磷酰胺处理小鼠免疫功能的比较研究 总被引:3,自引:0,他引:3
就β-胡萝卜素立体异构体对环磷酰胺处理小鼠的免疫功能影响进行了比较研究。结果显示β-胡萝卜素立体异构体对外磷酰胺造成的免疫功能低下具有不同程度的改善作用,提高胸腺和脾脏指数,增强脾脏细胞对刀豆素A(ConA)的反应性和NK活性,血清溶菌酶含量也有所增加。综合各项指标,9-顺式和全反式混合物的作用最明显,提示一定浓度的9-顺式对于提高β-胡萝卜素对机体的总体作用是有一定意义的。 相似文献
10.
Hitoshi Ogino Nongchana Klangsuk Wu Jin Christopher T. Bowles Magdi H. Yacoub 《Artificial organs》1995,19(6):525-534
Abstract: The dependence of transient pressure characteristics of a ventricular assist device (VAD) on the compliance of its housing and cannulas was investigated in a mock circulation. The peak rate of change of pressure ( dP/dt max ) values was greater in the cannulas than other compartments and was associated with valve closure-induced pressure oscillations. When cannula compliance was increased from 0.0057 to 0.0129 cm3 /mm Hg, these values decreased by ˜20%, and outflow cannula pressure oscillation frequency decreased from 17.5 Hz by 35%. This trend was also apparent in the inflow. A VAD housing compliance increase from 0.0162 to 0.0483 cm3 /mm Hg caused a dP/dt max decrease of 30% in both the blood chamber and the outflow cannula. The effect of this change on the inflow was weaker implying that housing absorbs the energy associated with outflow deceleration more effectively than the inflow. These findings suggest that increasing VAD housing and cannulas compliance can improve hydrodynamic performance. 相似文献