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Yue Chunfang Yin Liying 《国际中华应用心理学杂志》2005,2(3):178-181
There are the problems that influence English teaching, because the learners have the wrong understandings about the target needs and learning needs. The article analyses and discusses the teaching methods on dealing with the matter. The author thinks the teachers' adjustable function counting for much more. 相似文献
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重庆地区异常妊娠妇女弓形虫感染的调查分析 总被引:4,自引:0,他引:4
弓形虫 (Toxoplasmosis,TOX)是一种形似弦月状的胞内寄生虫 ,又称弓形体 ,它广泛寄生于动物身上 ,是一种人畜均可感染的寄生虫 ,分布于世界各地 ,人感染后均可引起弓形虫病。弓形虫病是一种严重危害母婴健康的寄生虫病 ,孕妇感染了弓形虫后 ,虽然其本人情况轻微 ,但可通过母婴垂直传播 ,导致胎儿多种器官受损而引起流产 ,死胎或新生儿中枢神经系统障碍。据不完全统计 ,全世界约有 5亿人感染了弓形虫 ,美国每年有 30 0 0多例先天性弓形虫病患儿出生 ,我国每年可能有 9万名先天性弓形虫病患儿出生。调查了解我市孕妇弓形虫感… 相似文献
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BACKGROUND: Under the normal circumstance, there exist some synapses with inactive functions in central nervous system (CNS), but these functions are activated following nerve injury. At the early stage of brain injury, the abnormal functions of brain are varied, and they have very strong plasticity and are corrected easily.
OBJECTIVE: To observe the changes of neuronal morphology in hippocampal CA1 region and memory function in newborn rats with hypoxic-ischemic encephalopathy(HIE) from ischemia 6 hours to adult.
DESIGN: Completely randomized grouping, controlled experiment.
SETTING: Taian Health Center for Women and Children; Taishan Medical College.
MATERIALS: Altogether 120 seven-day-old Wistar rats, of clean grade, were provided by the Experimental Animal Center, Shandong University of Traditional Chinese Medicine. Synaptophysin (SYN) polyclonal antibody was provided by Maixin Biological Company, Fuzhou.
METHODS: This experiment was carried out in the Laboratory of Morphology, Taishan Medical College between October 2000 and December 2003. ① The newborn rats were randomly divided into 2 groups: model group and control group, 60 rats in each group. Five rats were chosen from each group at postoperative 6 hours, 24 hours, 72 hours, 7 days, 2 weeks and 3 weeks separately for immunohistochemical staining. Fifteen newborn rats were chosen from each group at postoperative 4 weeks and 2 months separately for testing memory ability (After test, 5 rats from each group were sacrificed and used for immunohistochemical staining)② The right common carotid artery of newborn rats of model group was ligated under the anesthetized status. After two hours of incubation, the rats were placed for 2 hours in a container filled with nitrogen oxygen atmosphere containing 0.08 volume fraction of oxygen, thus, HIE models were created; As for the newborn rats in the control group, only blood vessels were isolated, and they were not ligated and hypoxia-treated. ③ Thalamencephal tissue sections of newborn rats of two groups were performed DAB developing and haematoxylin slight staining. Cells with normal nucleous in 250 μm-long granular layer which started from hippocampal CA1 region were counted with image analysis system under high-fold optical microscope (×600), and the thickness of granular layer was measured. The absorbance (A) of positive reactant of SYN in immunohistochemically-stained CA1 region was measured. Learning and memory ability were measured with step through test 3 times successively. ④ t test and paired t test were used for comparing intergroup and intragroup difference of measurement data respectively, and Chi-square for comparing the difference of enumeration data.
MAIN OUTCOME MEASURES: Comparison of cytological changes in hippocampal CA1 region and memory ability at different postoperative time points between two groups.
RESULTS: Totally 120 newborn rats were involved in the result analysis. ① Cell morphological changes in hippocampal CA1 region: In the control group, with aging, perikaryon, nucleus and nucleolus in cortex of parietal lobe were significantly increased, Nissl body was compacted, the amount of neurons was declined, but the A of SYN positive reactant was relatively increased. In the model group, at postoperative each time point, neurons were seriously shrunk and dark-stained, nucleus was contracted, chromatin was condensed, nucleolus was unclear, even cells disappeared, especially the cells in 6 hours and 24 hours groups. The amount of neurons with normal morphology in hippocampal CA1 region and granular layer thickness in the model group at postoperative each time point were significantly less or smaller than those in the control group at postoperative 6 hours respectively (t =3.002-1.254, P < 0.01). The A value of SYN positive reactant at postoperative 2, 3 and 4 weeks was significantly higher than that at previous time point (t =2.011-2.716,P < 0.05-0.01). ② Test results of learning and memory ability: In the first test, there was no significant difference in the ratio of rats which kept memory ability between two groups (P > 0.05); In the third test, the ratio of rats which kept memory ability in the model group was significantly lower than that in the control group at postoperative 4 weeks and 2 months[53%(8/15),100%(15/15);60%(9/15),93%(14/15),χ 2=2.863,2.901,P < 0.01].
CONCLUSION: The destroyed hippocampal structure induces the decrease of learning and memory ability of developmental rats. Early interference can increase the quality of neurons and also promote functional development of the nervous system. 相似文献
5.
临河地区发现异常血红蛋白 总被引:1,自引:0,他引:1
我们在对巴盟临河地区进行异常血红蛋白病普查中,发现一例G组慢泳异常血红蛋白。G Coushatta[β_(22)(B_4)-Glu→Ala]经理化性质测定及化学结构分析,证明是β链第22位Glu为Ala取代,与Hb G Cous-hatta为同一变异物。 1 材料和方法溶血液制备用CCl_4法,pH8.6TEB缓冲液醋纤膜电同本室常规。血红蛋白 (Hb)含量测定用光密度法pH6.25酸性琼脂电泳用Vella法。异丙醇实验用Carrel法热不稳定实验见参考文献。Hb H包涵体实验同参考文献。 相似文献
6.
LJM, a 41-year-old schizophrenic Chinese man with bilateral anterior cingulate gyrus (Brodmann's area 24) lesions and also a small lesion in right amygdala after an operation, was compared with normal as well as brain-damaged and schizophrenic controls in identification of morphed facial expressions of six basic emotions. In repeated administrations of the test for recognition of facial emotions, over a 1- year period, LJM performed significantly worse for expressions of fear compared with the three groups of controls. Recognition of other emotions was not significantly different from that of the controls, except that his recognition of disgust during the first session (but not in two subsequent sessions) was worse than normal and brain-damaged controls but not worse than schizophrenic controls. The dissociation between recognition of fear and other emotions supported the view that the brain has separable networks for processing different emotions, and that the right amygdala as well as the anterior part of bilateral cingulate gyrus are possible substrates involved in the special network for perception of fear. The results from the various groups of Chinese subjects indicate that they perceive emotions in a categorical manner, and that the six basic emotions are likely to be cross-cultural universals. 相似文献
7.
Since the publication of the AAPM Task Group 43 report in 1995, Model 200 103Pd seed, which has been widely used in prostate seed implants and other brachytherapy procedures, has undergone some changes in its internal geometry resulting from the manufacturer's transition from lower specific activity reactor-produced 103Pd ("heavy seeds") to higher specific activity accelerator-produced radioactive material ("light seeds"). Based on previously reported theoretical calculations and measurements, the dose rate constants and the radial dose functions of the two types of seeds are nearly the same and have already been reported. In this work, the anisotropy function of the "light seed" was experimentally measured and an averaging method for the determination of the anisotropy constant from distance-dependent values of anisotropy factors is presented based upon the continuous low dose rate irradiation linear quadratic model for cell killing. The anisotropy function of Model 200 103Pd "light seeds" was measured in a Solid Water phantom using 1 X 1 x 1 mm micro LiF TLD chips at radial distances of 1, 2, 3, 4, 5, and 6 cm and at angles from 0 to 90 degrees with respect to the longitudinal axis of the seeds. At a radial distance of 1 cm, the measured anisotropy function of the 103Pd "light seed" is considerably lower than that of the 103Pd "heavy seed" reported in the TG 43 report. Our measured values at all radial distances are in excellent agreement with the results of a Monte Carlo simulation reported by Weaver, except for points along and near the seed longitudinal axis. The anisotropy constant of the 103Pd "light seed" was calculated using the linear quadratic biological model for cell killing in 30 clinical implants. For the model 200 "light seed," it has a value of 0.865. However, our biological model calculations lead us to conclude that if the anisotropy factors of an interstitial brachytherapy seed vary significantly over radial distances anisotropy constant should not be used as an approximation for anisotropy characteristics of a brachytherapy seed. 相似文献
8.
A large area and highly sensitive thermoluminescent (TL) sheet film was used for two-dimensional dose distribution measurements at millimetre distances from a 103Pd interstitial brachytherapy source. The TL film is made of Teflon homogeneously mixed with small particles of thermoluminescent material (BaSO4: Eu doped). This TL sheet (5 cm x 5 cm) was used to determine the relative dosimetric characteristics (i.e., radial dose function, 2D and 1D anisotropy functions, as defined by the updated AAPM Task Group No 43 report) of the model 200 103Pd source that emits low energy photons (21 keV). The two-dimensional dosimetry data were obtained for distances from the source surface to 15 mm. The radial dose function measured with the TL sheet is in reasonable agreement within 11% with the values recommended in the updated AAPM TG-43 report. All the measured 2D dose distributions showed limited symmetry about the source axes. The differences between the 1D anisotropy function values measured with the TL sheet and the data recommended in the updated AAPM TG-43 report were 10% at 5 mm and 7.5% at 10 mm, respectively, for the model 200 103Pd seed. Our experiments have demonstrated that it is feasible to use the TL sheet as a dosimeter in the determination of the dosimetric characteristics in the immediate vicinity of interstitial brachytherapy sources emitting low energy photons. 相似文献
9.
Dopaminergic modulation of cortical activity has been implicated in the formation of reward associations. There is abundant evidence for dopaminergic effects on olfactory processing. Using an olfactory discrimination task, the authors show that D1 and D2 dopamine receptors can regulate rats' olfactory discrimination capacities and that the effects of receptor activation functionally oppose one another. Injection of either the D1 agonist SKF 38393 (10 mg/kg) or the D2 antagonist spiperone (0.62 mg/kg) facilitated the discrimination of similar odorants but had no effect on the discrimination of dissimilar odorants, whereas both the D, antagonist SCH 23390 (0.025 mg/kg) and the D2 agonist quinpirole (0.2 mg/kg) significantly impaired rats' ability to discriminate similar and dissimilar odorants. 相似文献
10.