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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
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N M Genev J R Flack P L Hoskins J E Overland D K Yue J R Turtle 《Diabetic medicine》1992,9(5):475-479
Two hundred Type 2 diabetic patients newly referred to the diabetes centre at a large university teaching hospital were studied over an 8-month period. Patients completed a diabetes knowledge questionnaire, and specified their educational priorities by selecting six diabetes-related topics from a list of 14. After giving 1 h of individual education and using the same list, the educators selected six topics which they considered to be most important for that particular patient to know. Choice of educational priorities differed between the patients and the corresponding educator (p less than 0.001). In only 38% of cases did the educators' first three priorities coincide with those of the patients. The major discrepancies were in the selection of 'sick day management' and 'complications', especially favoured by patients, as against 'oral hypoglycaemic agents' and other therapy-related topics, especially favoured by educators. Diabetes knowledge was a determinant of educational priority for patients (p less than 0.001) but not educators. In contrast, only the educators' overall choices were affected by duration of diabetes (p less than 0.001). Diabetes treatment type influenced both patients' and educators' selection of priorities (p less than 0.001). We conclude that an educational strategy which relies on health professionals' perceptions to determine what diabetic patients need to know may be inadequate. 相似文献
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Summary In this study the technique of labelling the cell membrane with DPH fluorescence polarization was used to observe the membrane
fluidity of B lymphocytic cell lines and tonsillar cells from healthy persons; the modulation effect on membrane-fluidity
induced by McAbs against isotypic and idiotypic determinants of IgM from patients with leukemia was studied as well. The expression
of the corresponding isotypic and idiotypic determinants of IgM on the cell membrane was determined. The results show that
the membrane fluidity of leukemic cell lines is remarkably higher than that of tonsillar cells from healthy persons, and McAbs
against isotypic determinants of leukemic IgM can enhance the membrane fluidity of all kinds of cells mentioned above. However,
the anti-idiotypic monoclonal antibody increased only the membrane fluidity of leukemic cell lines. These results indicated
that there was a close relationship between the effect of McAbs on cell membrane fluidity and the expression of corresponding
isotypic and idiotypic determinants of IgM on the cell membrane. 相似文献
25.
目的探讨常温及低温体外循环心脏直视手术对细胞因子及补体的影响。方法选择先天性和风湿性心脏病患者40例,随机分为常温组及低温组各20例,分别于术晨、体外循环结束时及术后1、4、7、14 d抽取患者静脉血标本,测定血浆TNF、IL-2、C3、C4值。结果两组术前各项检查指标无显著差异。(1)两组术后1~4 d的IL-2水平较术前显著下降,至术后7 d恢复正常。体外循环结束至术后4 d,低温组IL-2显著低于常温组。(2)体外循环结束时以及术后1、4、7 d,常温组TNF水平显著低于低温组。两组体外循环结束时及术后1、4 d均高于术前,常温组至术后7 d、低温组术后14 d恢复正常。(3)体外循环结束时及术后1、7 d,常温组C3水平高于低温组,术后4 d两组无差别;常温组及低温组于体外循环结束时、术后1、4 d均低于术前,至术后7 d常温组恢复正常,低温组至术后14 d恢复至术前水平。(4)两组体外循环结束时及术后1、4 d C4水平均低于术前。体外循环结束时、术后1 d,常温组C4水平高于低温组。结论常温体外循环心脏直视手术对细胞因子及补体的影响显著轻于低温组,因而对术后机体的恢复优于低温方法。 相似文献
26.
Most studies have been unable to identify reliable acoustic cues for the recognition of the English nonsibilant fricatives [see text]. The present study was designed to test the extent to which the perception of these fricatives by normal-hearing adults is based on other sources of information, namely, linguistic context and visual information. In Experiment 1, target words beginning with /f/, /theta/, /s/, or [see text] were preceded by either a semantically congruous or incongruous precursor sentence. Results showed an effect of linguistic context on the perception of the distinction between /f/ and /theta/ and on the acoustically more robust distinction between /s/ and [see text]. In Experiment 2, participants identified syllables consisting of the fricatives [see text] paired with the vowels /i, a, u/. Three conditions were contrasted: Stimuli were presented with (a) both auditory and visual information, (b) auditory information alone, or (c) visual information alone. When errors in terms of voicing were ignored in all 3 conditions, results indicated that perception of these fricatives is as good with visual information alone as with both auditory and visual information combined, and better than for auditory information alone. These findings suggest that accurate perception of nonsibilant fricatives derives from a combination of acoustic, linguistic, and visual information. 相似文献
27.
Molineux Graham; McCrea Clay; Yan Xiao Qiang; Kerzic Patrick; McNiece Ian 《Blood》1997,89(11):3998-4004
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直视下经尿道内切开术治疗尿道狭窄 总被引:6,自引:0,他引:6
目的:探讨直视下经尿道内次切开术治疗尿道狭窄的有效性和安全性。方法:总结直视下经尿道内切开术治疗68例尿道狭窄和闭锁患者的疗效和经验,63例1次手术成功;3例行2次、2例行3次成功。结果:68例中,57例术后随访3~71个月,平均28.3个月,43例(75%)均排尿通畅;2例暂时性尿失禁者分别于术后3~6月内恢复。结论:直视下经尿道内切开术创伤小,并发症少,疗效确切,是尿道狭窄和闭锁的首选治疗方法。 相似文献