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21.
普通高等学校医药类专业物理教师队伍现状调查分析 总被引:9,自引:2,他引:7
对全国28省(市)的69所普通高等学校医药类专业物理教师队伍现状进行了调查,分析讨论了普通高等学校医药类专业物理教师队伍面临的问题、原因和对策。 相似文献
22.
O. V. Karachentseva V. N. Yartsev D. P. Dvoretsky I. V. Zhdanova 《Acta physiologica (Oxford, England)》2005,185(2):99-107
Aim: Dependence of the melatonin‐evoked potentiation of the rat tail artery neurogenic reactivity on degree of the change in the reactivity was studied. Method: Electrical field stimulation‐evoked contractile response of the juvenile rat tail artery segment under isometric conditions was recorded. 0.1 μm melatonin was administered after the change in the response produced both spontaneously and by acidification (pH 6.6) or alkalinization (pH 7.8) of the solution. Results: During the course of experiment, the contraction force continuously declined, being reduced by 12 ± 5, 24 ± 7 and 32 ± 6% at 20, 70, and 170 min after beginning of experiment, respectively. Melatonin applied at these time points increased the contraction by 20 ± 5, 41 ± 10, and 48 ± 8%, respectively, relative to control. This increase in potentiating effect of melatonin during the course of experiment was not because of sensitization of the segment to the hormone. Acidosis‐induced considerable decline in neurogenic contraction was counteracted by melatonin, while after alkalosis‐induced augmentation in the contraction the hormone was not effective. Melatonin increased the artery response to 0.1 μm noradrenaline. Conclusion: These data suggest that melatonin can restore an attenuated neurogenic reactivity of the juvenile rat tail artery. The effect is more pronounced with further decrease in reactivity and might be due to a change in sensitivity of the post‐junctional membrane to noradrenaline. 相似文献
23.
Efficient high-frequency body coil for high-field MRI. 总被引:1,自引:0,他引:1
J T Vaughan G Adriany C J Snyder J Tian T Thiel L Bolinger H Liu L DelaBarre K Ugurbil 《Magnetic resonance in medicine》2004,52(4):851-859
The use of body coils is favored for homogeneous excitation, and such coils are often paired with surface coils or arrays for sensitive reception in many MRI applications. While the body coil's physical size and resultant electrical length make this circuit difficult to design for any field strength, recent efforts to build efficient body coils for applications at 3T and above have been especially challenging. To meet this challenge, we developed an efficient new transverse electromagnetic (TEM) body coil and demonstrated its use in human studies at field strengths up to 4 T. Head, body, and breast images were acquired within peak power constraints of <8 kW. Bench studies indicate that these body coils are feasible to 8 T. RF shimming was used to remove a high-field-related cardiac imaging artifact in these preliminary studies. P41RR13230 相似文献
24.
目的 研究应用个体化营养方案对慢性阻塞性肺疾病 (COPD)患者进行营养治疗后的病情变化 ,评价个体化营养方案对病情的影响 ,阐明个体化营养方案的治疗价值。方法 选择 80例COPD患者 ,随机分为实验组与对照组 ,实验组应用个体化方案进行营养治疗 ,对照组采用普通膳食 ,观察营养状况、临床表现、病情急性发作次数、住院次数、治疗费用、并发症、呼吸衰竭发生率、死亡率、肺通气功能的变化。结果 实验组营养状况显著好于对照组P <0. 0 5 ,实验组病情急性发作次数、住院天数减少 ,治疗费用降低 ,与对照组比 ,差异显著P <0 . 0 5 ,实验组临床表现减轻 ,与对照组比差异显著P <0 . 0 5 ,实验组患者肺功能有所改善 ,差异显著P <0 . 0 5 ,实验组并发症、呼衰发生率、死亡率与对照组比显著降低P <0 . 0 5。结论 个体化营养方案简便易行、科学、经济 ,患者易接受 ,应用该个体化营养方案对COPD患者实施营养支持 ,营养效果明显 ,能确切改善患者病情。 相似文献
25.
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
26.
BACKGROUND: The hamster cheek-pouch carcinogenesis model is a well-known animal system that closely mimics the development of premalignant and malignant lesions in human oral cancer. Our aim was to numerically characterize the premalignant and malignant lesions and expressions of field cancerization in this model using ploidy as the end-point. METHODS: To study the DNA content and proliferation status of the cells in this model we assessed the Feulgen reaction and the immunohistochemical reaction for 5-bromo-2-deoxiuridine (BrdU) in different histological areas of serial tissue sections of the cheek pouches of animals injected with BrdU. RESULTS: Ploidy values were higher in cancerized epithelia with no unusual microscopic features (NUMF), in preneoplastic and tumor areas than in control epithelia. The aneuploidy index was higher in NUMF areas than in control and differed significantly from control in preneoplastic areas and carcinoma. CONCLUSIONS: The unexpected alteration in DNA content observed in NUMF epithelia is of great relevance as a biomarker of field cancerized areas. 相似文献
27.
Purpose. To estimate disease activity in patients with systemic sclerosis using contrast-enhanced MRI of the skin.
Material and Methods. In a pre-study, sequences of a low-field (0.2 T) scanner (Artoscan, Esaote, Genova, Italy) were optimized for detection of
intravenous contrast (0.1 mmol/l Gd-DTPA) in six patients with the autoimmune disease systemic scleroderma. Based on the results
of the pre-study, 17 patients with scleroderma (7 sclerotic/10 active inflammatory disease) were scanned using gradient-spoiled
3D GRE sequences (FA 90 °, TR 100 ms, TE 18 ms), which had been established as most sensitive for intravenous contrast. Contrast
enhancement of the skin was determined quantitatively by contrast-to-noise ratios (CNR), comparing post- to pre-contrast and
dynamic scans (for 6 min, 1 acquisition/min). Patients in the chronic state with sclerodactylia and active inflammation of
the hands were considered separately and compared to a control group (n = 10) matched according to age.
Results. CNR increase after intravenous contrast was significantly higher in patients with active disease (86 ± 16 % increase) than
sclerosing disease (29 ± 3 %, p < 0.05) and the control group (4 ± 2 %, p < 0.05). The dynamic examination showed a significantly slower decrease after the peak rise in the first minute in patients
with active disease (CNR 15.4 ± 0.7 to 14.2 ± 1.4) than in those with chronic disease (14.1 ± 0.5 to 11.3 ± 0.9, p < 0.05).
Discussion. Capillary leakage is the most likely explanation for the increased enhancement in patients with active scleroderma. Using
sequences optimized for contrast detection, disease activity in the course of scleroderma and response to therapy can be determined
by MRI in the future.
相似文献
28.
Ureteropelvic junction obstruction was noted in a newborn male infant with acro-pectoro-renal field defect. To our knowledge, this association has not previously been reported. Ultrasonography of the urinary tract should be performed on all children with aplasia of the pectoralis major muscle. 相似文献
29.
石刻雕塑作业劳动卫生学调查及实验研究 总被引:1,自引:0,他引:1
测定了石雕作业粉尘浓度,几何平均浓度为82.35~3.67mg/m3。工人职业性健康检查结果,接尘工人的咽部充血、咳嗽、咯痰检出率高于对照组;肺功能低下的检出率也高于对照组。该厂自1972年以来发生尘肺患者17例,其病情发展和晋期缓慢,发病工龄长。动物实验研究表明,石雕粉尘有轻微的致纤维化作用。 相似文献
30.
高频电磁场对工人行为功能的影响 总被引:6,自引:0,他引:6
采用世界卫生组织推荐的神经行为核心测试组合(WHO-NCTB),对高频作业工人41名(平均工龄13.9a(年)及年龄、性别、文化程度与接触组相匹配的对照组工人39名(平均工龄13.3a)分别进行了行为功能测试。结果表明高频作业工人部分情感状态得分和某些行为功能得分与对照组相比差异有显著性。长期接触高频电磁场可能引起工人情感状态改变,记忆力减退、注意力分散及心理运动稳定度下降。 相似文献