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61.
62.
英语阅读障碍儿童词汇命名加工特征的研究 总被引:1,自引:1,他引:0
目的研究英语阅读障碍儿童操作英语词汇的相关能力 ,探索英语阅读障碍的表现特点与矫治的手段。方法英语真、假词命名实验 ,观察 3 4名阅读障碍儿童和 3 4名对照组儿童的实验结果。结果 ( 1)障碍组右视野在真、假词的命名时间上与对照组存在显著差异 ;( 2 )障碍组在真词和假词上的命名错误率均大于正常组 ,假词命名的错误率大幅增加。 ( 3 )障碍组右视野的真词命名时间明显长于左视野 ,假词命名的错误率也明显大于左视野。结论英语阅读障碍的儿童显示出了操作英语语音能力的欠缺以及左测大脑半球活动水平不足的倾向。 相似文献
63.
This paper reports the morphometric analysis results of 100 cases of bladder tumor cells with a Q-900 computer-assisted image analysis system. According to the nuclear area, axis ratio and area ratio of tumor nuclei, bladder transitional cell tumors were divided into 4 grades. This system is called the morphometric grading system (M grading). The results show that the higher the M grading, the lower the survival rate and the higher the recurrence rate. As the M grade increases the tumors could be accompanied by muscular invasion. When recurring, the tumor has a poor prognosis if M grading increases. We conclude that the morphometric grading system is able to yield a quantitative pathologic diagnosis and can predict the biological behavior of bladder tumors. Recently, new techniques for diagnosing and predicting the biological behavior of bladder tumors have been developed. One such technique is morphometric analysis of bladder transitional cell carcinoma with computer-assisted image instruments [1]. Because this morphometric method is easily applicable to pathological section routinely stained with HE and the results are reproducible and more objective, the studies about morphometric analysis of bladder tumor have increased in recent times. This paper reports the preliminary morphometric analysis results of bladder tumor cells examined by a Q-900 image analysis instrument for 100 cases. 相似文献
64.
发挥远程教育优势推进医学继续教育发展 总被引:9,自引:0,他引:9
《教育部关于加强高校网络教育学院管理提高教学质量的若干意见》中强调指出:高校网络教育学院要以在职人员的继续教育为主,要充分发挥网络教育的优势,为在职人员更新知识、增强技能、不断学习、不断提高提供良好的服务。然而,要使医学院校在开展继续教育中发挥更大的作用,推进医学继续教育的发展,远程教育不仅是解决这一问题的有效途径,而且将成为开展医学继续教育的强大动力。 相似文献
65.
66.
Lee L. Q. Pu 《European journal of plastic surgery》2007,30(1):19-24
A soleus flap as a local reconstructive option for soft-tissue coverage of a tibial wound in the distal third of the leg has
never been well recognized. In a 2-year period, seven patients underwent reconstruction of a less extensive tibial wound (4 × 3
to 10 × 4 cm) in the distal third of the leg after orthopedic trauma with the laterally extended medial hemisoleus flap. The
flap was elevated with emphasis on the preservation of the most distal perforators from the posterior tibial vessels to the
flap as possible while allowing adequate rotation of the flap to cover the exposed tibia and/or hardware and on the possible
preservation of foot planter flexion by reconstruction of the proximal Achilles’ tendon. In this series, there was no total
or partial flap loss. All patients healed their tibial wounds primarily with reliable soft-tissue coverage, evidenced fracture
healing, and good cosmetic outcome during follow-up. Thus, the laterally extended medial hemisoleus flap described by the
author can be a reliable option for soft-tissue coverage of a less extensive tibial wound in the distal third of the leg.
It offers a more cost-effective approach for managing this unique problem and can be performed by most reconstructive surgeons
without microsurgical expertise. 相似文献
67.
68.
S. Friedman R. Komorowski W. Maillet H. Q. Nguyen C. D. Torneck 《Dental traumatology》1998,14(5):225-231
Abstract— NdYAG laser-induced modification of the root surface may inhibit development of external inflammatory resorption in replanted teeth. This study tested this hypothesis in vivo. The pulp chambers of six mandibular premolars in each of two dogs were accessed, inoculated with plaque, and sealed (Groups 1, 2). Two additional premolars in each dog were endodontically treated without inoculation (Groups 3, 4). After 2 weeks, teeth were hemisected and extracted. Each root had a 2times3 mm surface area denuded of cementum on the buccal and lingual surface. In Groups 1 (n= 12 roots) and 3 (n=4), the denuded surfaces were wiped with 15% EDTA, coated with black ink, and irradiated with Nd:YAG laser (0.75 W, 15 ppc, 300 pm tip, 20 s). In Groups 2 (n= 12) and 4 (n= 4), the surfaces were wiped with 15% EDTA, and rinsed with sterile saline for 20 s. Roots were replanted within 5 min. The dogs were perfwion-euthanised 10 weeks after replantation. Block specimens were removed, decalcified, embedded and horizontally sectioned (6 pm) at 180-pm intervals, resulting in 10 to 14 cross-sections of each root. From these, the middle five consecutive sections were stained with hematoxylin and eosin, and observed by light microscopy for occurrence of surface, inflammatory and replacement resorption on the denuded surfaces. No obvious differences were noted between the laser-irradiated and non-irradiated surfaces. Inflammatory resorption was frequent in Groups 1 and 2, and absent in Groups 3 and 4. Replacement resorption was minimal in Groups 1 and 2, and frequent in Groups 3 and 4. Differences between Groups 1 and 2, and between Groups 3 and 4 were not significant, whereas the differences between the two pairs of groups were statistically significant (chi-square and two-way ANOVA, P>0.006). These results did not support the hypothesis, and questioned the clinical validity of the surface modification in NdYAG laser-irradiated den-tin. Therefore, the clinical application of NdYAG laser to the root surfaces of replanted teeth is not warranted. 相似文献
69.
Q. Peng J. Moan Jahn M. Nesland Jan F. Evensen M. Kongshaug C. Rimington 《Lasers in medical science》1990,5(4):399-409
Observations on time-dependent localization of tetra(3-hydroxyphenyl)porphin (3-THPP) in human malignant melanoma transplanted to athymic nude mice from 1 to 120 h after intraperitoneal (i.p.) 10 mg kg–1 b.w. administration were made by means of fluorescence microscopy. Fluorescence was found on the membrane of the melanoma cells and in the cytoplasm with a peak fluorescence intensity at 24 h post-injection of 3-THPP. The growth of the tumour cells was obviously inhibited at an early stage after PCT. Morphological changes of the tumour at various intervals after treatment by PCT with 3-THPP were also observed. Diffuse degeneration of the tumour cells with swelling of mitochondria and endoplasmic reticulum, heterochromatin aggregation and margination, etc., and subsequently diffuse necrosis with little or no the background of tumorous vascular response were found at an early stage after PCT. On the other hand, it was also observed that the necrosis of the melanoma areas was caused as a consequence of tumorous vascular injury at a later stage after PCT. Thus, two tumoricidal processes caused by PCT with 3-THPP were seen: a direct phototoxic action on tumour cells at an early stage after PCT and an indirect effect secondary to tumorous vascular injury at a later period after PCT. 相似文献
70.
Poverty, health services, and health status in rural America 总被引:5,自引:0,他引:5
Access to health services for everyone has been a major policy goal in the United States: inequitable access is assumed to lead to inequitable health status, particularly for low-income groups. A sophisticated model of the relation between poverty, health care needs, service use, and health outcomes is used to analyze cross-sectional data on 7,823 adults from 36 rural communities. Improved access and use are helpful, but evidence clearly indicates that combined health and social initiatives will be necessary to reduce inequalities in health status. 相似文献