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Morphological and functional changes in the blood-spinal cord barrier of rabbits in an experimental spinal cord presyrinx state 被引量:2
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作者 Jianfeng Li1, Haiying Liu1, Qingjun Zhang2 1Department of Neurosurgery, Fourth Hospital, Hebei Medical University, Shijiazhuang 050011, Hebei Province, China 2Department of Neurosurgery, People’s Hospital, Peking University, Beijing 100044, China 《Neural Regeneration Research》 SCIE CAS CSCD 2006年第7期597-600,共4页
BACKGROUND: Presyrinx state of spinal cord can reflect the initial lesion of syringomyelia (SM). The early trials has proved that ischamia and edema are main pathological changes of presyrinx state. OBJECTIVE: To esta... BACKGROUND: Presyrinx state of spinal cord can reflect the initial lesion of syringomyelia (SM). The early trials has proved that ischamia and edema are main pathological changes of presyrinx state. OBJECTIVE: To establish SM model of rabbits for investigating the relationship between changes of morphous and function of blood-spinal cord barrier and the edema degree, histological changes in presyrinx state of SM, and to explore the mechanism of the presyrinx state of SM. DESIGN: Randomized controlled animal experiment. SETTING: Department of Neurosurgery, Fourth Hospital, Heibei Medical University. MATERIALS: Sixty Chinese healthy white rabbits, aged 3.5-4.5 months, weighing 1.5-2.0 kg, were provided by Experimental Animal Center of Hebei Medical University [certification: (SYXK(Ji)2003-0026)]. Evan's blue (EB) and dimethylformamide (DMF) were purchased from Jingmei Biotech Co., Ltd. RM2125 paraffin section cutter (Leica Company, Japan), H-7500 transmission electron microscope (Hitachi Company, Japan), PM-20 light microscope photograph system (Olympus Company, Japan). METHODS: The experiment was carried out in the Laboratory of Neurosurgery Department, Second Hospital of Hebei Medical University from January to June 2006. ① All the rabbits were randomly divided into two groups: model group (n =40), control group (n =20). Rabbits in two groups were divided into five subgroups once again at five time points (1st, 3rd, 7th, 14th, 21st days, n =8 and n =4 at each time point in the model group and control group, respectively). Under ketamine anesthesia, 0.6 mL Kaolin solution (250 g/L, 37 ℃) was injected into the cisterna magna of rabbits in model group, while 0.6 mL physiological saline (37 ℃) was injected into the rabbits of control group. ② On the 1st, 3rd, 7th, 14th, 21st days after kaolin injection, cervical cord samples were harvested after sacrifice of animal. Quantitative analysis on the function of blood-spinal cord barrier was performed by Evan's blue technique. Water content of spinal cord was measured by dry-wet weighing technique. Samples were fixed in 40 g/L paraform for haematoxylin and eosin staining. Pathological and ultramicrostructural observation was carried out under a light microscope and H-7500 electron microscope, respectively. ③ The comparison of measurement data was performed with analysis of variance. MAIN OUTCOME MEASURES: The changes of water content, Evan's blue content and pathology in upper cervical cord of presyrinx state at different time points. RESULTS: All the 60 rabbits were involved in the result analysis. ① Ultramicrostructural observation: During the whole process of occurrence and development of presyrinx state of spinal cord, no obvious morphological changes of blood-spinal cord barrier were found. Microvascular endothelial cells were in integrity in morphology, basal membrane was continuous and smooth, and the structure of tight junction was not destructed remarkably. ②Water content of spinal cord: Compared with control group, the water content of spinal cord was increased on the 1st day [(68.35±0.7)% vs.(66.51±0.32)%, F =7.387, P =0.026] after kaolin injection, more prominent on the 3rd day [(72.70±0.88)%, F =123.48, P =0.000], reached its peak on the 7th-14th day [(72.92±0.86)%, F =135.94, P =0.000; (72.18±0.55)%, F =28.18, P =0.001], and was declined slowly after 21 days[(70.03±0.77)%,F =11.51, P =0.009], but it was still higher than that of control group [(65.98±0.56)%, F = 11.51, P =0.009].③ Evan's blue content in spinal cord tissue: It started to rise on the 3rd day after operation [(2.79±0.42) mg/L, F =61.35, P =0.000], reached its peak on the 7th day [(3.53±0.45) mg/L, F =528.35, P =0.000], and kept this high level till the 14th day [(3.45± 0.35) mg/L, F =326.57, P =0.000]. It decreased on the 21st day [(3.36±0.27) mg/L], but was still higher than normal level[(1.69±0.16)mg/L,F = 58.63,P =0.000]. ④ Neurologic function score: The neurologic function score of rabbits in the model group was close to that in the control group preoperatively and on the postoperative 1st and 3rd days (F =2.667, P =0.141);Abnormal nerve function appeared on the postoperative 7th day (F =32.667, P =0.00), and the neurologic function scores were gradually decreased with the elongation of time. The neurologic function scores in the model group were significantly lower than those in the control group on the postoperative 14th and 21st days (F =42.667, 34.571,P =0.00). CONCLUSION: Under the presyrinx state of spinal cord of experimental rabbits, the destruction of blood-spinal cord barrier of spinal cord and spinal edema co-exist with the same changing tendency. Although morphological integrity of blood-spinal cord barrier is kept, the function of blood-spinal cord barrier was destroyed in the early stage and permeability is increased. This functional disorder plays an important role in the occurrence and development of presyrinx state of SM. 展开更多
关键词 Morphological and functional changes in the blood-spinal cord barrier of rabbits in an experimental spinal cord presyrinx state
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Coseismic Coulomb stress changes induced by a 2020-2021 M_(W)>7.0 Alaska earthquake sequence in and around the Shumagin gap and its influence on the Alaska-Aleutian subduction interface
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作者 Lei Yang Jianjun Wang Caijun Xu 《Geodesy and Geodynamics》 EI CSCD 2024年第1期1-12,共12页
Three M_(W)>7.0 earthquakes in 2020-2021 occurred in the Shumagin seismic gap and its adjacent area of the Alaska-Aleutian subduction zone,including the Mw7.8 Simeonof thrust earthquake on July 22,2020,the M_(W)7.6... Three M_(W)>7.0 earthquakes in 2020-2021 occurred in the Shumagin seismic gap and its adjacent area of the Alaska-Aleutian subduction zone,including the Mw7.8 Simeonof thrust earthquake on July 22,2020,the M_(W)7.6 Sand Point strike-slip earthquake on October 19,2020,and the M_(W)8.2 Chignik thrust earthquake on July 29,2021.The spatial and temporal proximity of these three earthquakes prompts us to probe stress-triggering effects among them.Here we examine the coseismic Coulomb stress change imparted by the three earthquakes and their influence on the subduction interface.Our results show that:(1)The Simeonof earthquake has strong loading effects on the subsequent Sand Point and Chignik earthquakes,with the Coulomb stress changes of 3.95 bars and 2.89 bars,respectively.The Coulomb stress change caused by the Sand Point earthquake at the hypocenter of the Chignik earthquake is merely around 0.01 bars,suggesting the negligible triggering effect on the latter earthquake;(2)The triggering effects of the Simeonof,Sand Point,and Chignik earthquakes on aftershocks within three months are not well pronounced because of the triggering rates of 38%,14%,and 43%respectively.Other factors may have played an important role in promoting the occurrence of these aftershocks,such as the roughness of the subduction interface,the complicated velocity structure of the lithosphere,and the heterogeneous prestress therein;(3)The three earthquakes caused remarkable coseismic Coulomb stress changes at the subduction interface nearby these mainshocks,with an average Coulomb stress change of 3.2 bars in the shallow region directly inwards the trench. 展开更多
关键词 The 2020-2021 Alaska earthquake SEQUENCE Coseismic Coulomb stress change Mainshock-aftershock triggering The Alaska-Aleutian subduction interface The Shumagin gap
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Changes in cortical activation patterns accompanying somatosensory recovery in a stroke patient: a functional magnetic resonance imaging study 被引量:3
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作者 Yong Hyun Kwon Mi Young Lee 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第15期1485-1488,共4页
The somatosensory system plays a crucial role in executing precise movements by providing sensory feedback (Farrer et al., 2003; Rabin and Gordon, 2004). Somatosensory dys- function is a common problem following str... The somatosensory system plays a crucial role in executing precise movements by providing sensory feedback (Farrer et al., 2003; Rabin and Gordon, 2004). Somatosensory dys- function is a common problem following stroke. In partic- ular, somatosensory impairments, such as impairment in touch, proprioception, light touch, and vibration have been frequently observed (Carey et al., 1993; Sullivan and Hed- man, 2008; Tyson et al., 2008). Patients with somatosensory dysfunction show negative effects on motor control, and it sometimes becomes difficult to perform daily activities independently. 展开更多
关键词 SMA changes in cortical activation patterns accompanying somatosensory recovery in a stroke patient a functional magnetic resonance imaging study
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Functional changes after spinal lesions: implications for interventions 被引量:1
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作者 David Parker 《Neural Regeneration Research》 SCIE CAS CSCD 2018年第5期811-812,共2页
We have known for many years that the spinal cord can generate some basic locomotor outputs under specific experimental conditions without any input from the brain or the periphery(Stuart and Hultborn,2008).However,... We have known for many years that the spinal cord can generate some basic locomotor outputs under specific experimental conditions without any input from the brain or the periphery(Stuart and Hultborn,2008).However,when inputs from the brain are lost following spinal cord injury(SCI),the mammalian spinal cord is unable to generate normal,goal-directed locomotor outputs. 展开更多
关键词 functional changes after spinal lesions implications for interventions
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Assessing Sexual Function amongst Hong Kong Chinese Patients with Gynecological Cancer: Translation and Validation of the Sexual Function-Vaginal Changes Questionnaire (SVQ) 被引量:1
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作者 Ka-ming CHOW Winnie K.W. SO Carmen W.H. CHAN 《Clinical oncology and cancer researeh》 CAS CSCD 2010年第4期230-233,共4页
OBJECTIVE The study aims to translate the Sexual FunctionVaginal Changes Questionnaire (SVQ) into Chinese and to establish its psychometric properties.METHODS A Chinese SVQ was developed by the use of the Brislin mo... OBJECTIVE The study aims to translate the Sexual FunctionVaginal Changes Questionnaire (SVQ) into Chinese and to establish its psychometric properties.METHODS A Chinese SVQ was developed by the use of the Brislin model of translation. The content validity and semantic equivalence were assessed by an expert panel. The translated version of SVQ was administered to 75 Hong Kong Chinese women who were suffered from gynecological cancer to test its psychometric properties.RESULTS The Chinese version of SVQ was compared to the original study for factor analysis. Internal consistency, itemtoscale correlations and test-retest reliability were high. The convergent and divergent validities supported the Chinese SVQ to CONCLUSION We conclude that the Chinese SVQ appears to be a valid, reliable and feasible disease-specific tool for the assessment of sexual function among Chinese patients. 展开更多
关键词 sexual function-vaginal changes questionnaire sexual function Hong Kong Chinese
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Time-dependent effects of castration on the bladder function and histological changes in the bladder and blood vessels
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作者 Tomohiro Magari Yasuhiro Shibata +3 位作者 Seiji Arai Bunzo Kashiwagi Keiji Suzuki Kazuhiro Suzuki 《Asian Journal of Andrology》 SCIE CAS CSCD 2014年第3期457-460,共4页
We examined the effect of androgens on bladder blood flow (BBF), bladder function and histological changes in castrated male rats. Male Wistar rats were classified into unoperated group (control group), groups cas... We examined the effect of androgens on bladder blood flow (BBF), bladder function and histological changes in castrated male rats. Male Wistar rats were classified into unoperated group (control group), groups castrated at the age of 8weeks (group 8wPC) and groups castrated at the age of 4weeks (group 4wPC). Each rat was used at the age of 20weeks. BBF was measured using fluorescent microspheres. Bladder cystometry was performed without anesthesia or restraint; the bladder was first irrigated with saline and then with 0.25% acetic acid (AA) solution. Maximum voiding pressure and voiding interval were measured. The bladder and lilac artery were histologically examined for differences in smooth muscle and quantity of collagen fiber to analyze the effect of castration on the smooth muscle content. No differences were noted in BBF following castration. The voiding intervals for all groups were shortened (P 〈 0.001) following AA irrigation. No significant difference was noted in the maximum voiding pressure. Histological changes were observed in bladder and lilac artery. Smooth muscle/collagen ratio at the bladder was lower in groups 8wPC and 4wPC compared to the control group (P 〈 0.01), while that at the lilac artery was decreased in group 4wPC compared to the control group (P〈 0.001). In conclusion, our findings indicate that castration does not alter BBF, but leads to histological changes in the bladder as well as its associated blood vessels. 展开更多
关键词 bladder blood flow bladder function CASTRATION fluorescent microsphere method histological changes smooth muscle/collagen ratio
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Existence of Monotone Positive Solution for a Fourth-Order Three-Point BVP with Sign-Changing Green’s Function
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作者 Junrui Yue Yun Zhang Qingyue Bai 《Open Journal of Applied Sciences》 2024年第1期63-69,共7页
This paper is concerned with the following fourth-order three-point boundary value problem , where , we discuss the existence of positive solutions to the above problem by applying to the fixed point theory in cones a... This paper is concerned with the following fourth-order three-point boundary value problem , where , we discuss the existence of positive solutions to the above problem by applying to the fixed point theory in cones and iterative technique. 展开更多
关键词 Fourth-Order Three-Point Boundary Value Problem Sign-changing Green’s function Fixed Point Index Iterative Technique Monotone Positive Solution EXISTENCE
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The Pursuit of Fallacy in Density Functional Theory: The Quest for Exchange and Correlation, the Rigorous Treatment of Exchange in the Kohn-Sham Formalism and the Continuing Search for Correlation
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作者 A. Gonis 《World Journal of Condensed Matter Physics》 2014年第3期200-225,共26页
As pointed out in the paper preceding this one, in the case of functionals whose independent variable must obey conditions of integral normalization, conventional functional differentiation, defined in terms of an arb... As pointed out in the paper preceding this one, in the case of functionals whose independent variable must obey conditions of integral normalization, conventional functional differentiation, defined in terms of an arbitrary test function, is generally inapplicable and functional derivatives with respect to the density must be evaluated through the alternative and widely used limiting procedure based on the Dirac delta function. This leads to the determination of the rate of change of the dependent variable with respect to its independent variable at each isolated pair, , that may not be part of a functional (a set of ordered pairs). This extends the concept of functional derivative to expectation values of operators with respect to wave functions leading to a density even if the wave functions (and expectation values) do not form functionals. This new formulation of functional differentiation forms the basis for the study of the mathematical integrity of a number of concepts in density functional theory (DFT) such as the existence of a universal functional of the density, of orbital-free density functional theory, the derivative discontinuity of the exchange and correlation functional and the extension of DFT to open systems characterized by densities with fractional normalization. It is shown that no universal functional exists but, rather, a universal process based only on the density and independent of the possible existence of a potential, leads to unique functionals of the density determined through the minimization procedure of the constrained search. The mathematical integrity of two methodologies proposed for the treatment of the Coulomb interaction, the self-interaction free method and the optimized effective potential method is examined and the methodologies are compared in terms of numerical calculations. As emerges from this analysis, the optimized effective potential method is found to be numerically approximate but formally invalid, contrary to the rigorously exact results of the self-interaction-free method. 展开更多
关键词 DENSITY functional THEORY Variational Properties of DENSITY functional THEORY Self-Interaction Error Optimized Effective Potential functional DERIVATIVE Parametric DERIVATIVE functional Rate of change DERIVATIVE Discontinuity Orbital-Free DENSITY functional THEORY EXchangE and CORRELATION functional
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THE EFFECT OF MOXIBUSTION ON THE CHANGES OF 5-HT AND IMMUNE FUNCTION OF RAT INFECTED WITH EHFV
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作者 宋小鸽 唐照亮 +5 位作者 刘冰怀 产美英 程惠娟 周眉声 董朝阳 倪大石 《World Journal of Acupuncture-Moxibustion》 1996年第4期45-48,共4页
Authors observated the effect of moxibustion on changes of 5-HT and immunefunction of rat infected with EHFV.The results show that moxibustion could enhance the phago-cytosis of peritoneal macrophage of rat infected w... Authors observated the effect of moxibustion on changes of 5-HT and immunefunction of rat infected with EHFV.The results show that moxibustion could enhance the phago-cytosis of peritoneal macrophage of rat infected with EHFV,increase the roset rate of RBC C<sub>3</sub>brecptor,decrease the content of 5-HT in plasma.There is a significant dffeerence between EHFVinfected group and moxibustion group.That suggests the moxibustion could enhance the immunefunction of body,regulate the metablic disturbance of 5-HT in plasma,maintain the internal en-vironment of body and enhance the force of body to anti EHFV.Maybe that can play an impor-tant role in the mechanism of moxibustion treating EHF. 展开更多
关键词 Epidemic HEMORRHAGIC Fever(EHF) MOXIBUSTION IMMUNOLOGICAL function 5- HT
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Free Vibration of Geometrically Nonlinear Functionally Graded Micro-switches under Electrostatic Force and Temperature Change
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作者 Xiaoli Jia Chengbao Feng Kun Tang 《Journal of Mechanics Engineering and Automation》 2015年第1期26-32,共7页
The free vibration characteristics of functionally graded micro-switches under combined electrostatic, axial residual stress and temperature change is investigated, with an emphasis on the effect of geometric nonlinea... The free vibration characteristics of functionally graded micro-switches under combined electrostatic, axial residual stress and temperature change is investigated, with an emphasis on the effect of geometric nonlinear deformation due to mid-plane stretching, the influence of volume fraction profile parameter and temperature change. The micro-switch considered in this study is made of either homogeneous material or non-homogeneous functionally graded material with two material phases. Taking the temperature-dependency of the effective material properties into consideration, the Voigt model is used to simulate the material properties of the FGMs (functionally graded materials). The principle of virtual work is used to derive the nonlinear governing differential equation. The eigenvalue problem which describes free vibration of the micro-beam at its statically deflected state is then solved using DQM (differential quadrature method). The natural frequencies of clamped-clamped micro-switches are obtained. The solutions are validated through direct comparisons with experimental results reported in previous studies. A parametric study is conducted to show the effects of geometric nonlinearity, material composition, temperature change and geometrical parameters for the natural frequencies. 展开更多
关键词 Micro-switch free vibration functionally graded materials temperature change
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Anatomical changes in the somatosensory system after large sensory loss predict strategies to promote functional recovery after spinal cord injury
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作者 Chia-Chi Liao Jamie L.Reed Hui-Xin Qi 《Neural Regeneration Research》 SCIE CAS CSCD 2016年第4期575-577,共3页
Among cases of spinal cord injury are injuries involving the dorsal column in the cervical spinal cord that interrupt the major cutaneous afferents from the hand to the cuneate nucleus(Cu)in the brainstem.Deprivatio... Among cases of spinal cord injury are injuries involving the dorsal column in the cervical spinal cord that interrupt the major cutaneous afferents from the hand to the cuneate nucleus(Cu)in the brainstem.Deprivation of touch and proprioceptive inputs consequently impair skilled hand use. 展开更多
关键词 DCL Anatomical changes in the somatosensory system after large sensory loss predict strategies to promote functional recovery after spinal cord injury
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Changes in hippocampal neurons and memory function during the developmental stage of newborn rats with hypoxic-ischemic encephalopathy
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作者 Chuanjun Liu1, Yue Li2, Huiying Gao3 1Department of Pediatric Internal Medicine, Taian Health Center for Women and Children,Taian 271000, Shandong Province, China 2Department of Anatomy, 3Department of Histology and Embryology, Taishan Medical College, Taian 271000, Shandong Province, China 《Neural Regeneration Research》 SCIE CAS CSCD 2006年第8期681-684,共4页
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 injur... 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. 展开更多
关键词 changes in hippocampal neurons and memory function during the developmental stage of newborn rats with hypoxic-ischemic encephalopathy
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Cardiac functional and ultrastructural changes in early diabetic cardiomyopathy rabbits
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作者 DONG Rui-min,XIE Xu-jing,ZHENG Zheng-da,XIONG Zhao-jun (Department of Cardiology The Third Affiliated Hospital of Sun Yat-sen University Guangzhou 510012,China) 《岭南心血管病杂志》 2011年第S1期242-243,共2页
Objectives It is not fully clarified how diabetes mellitus induced cardiac dysfunction and myocardial ultrastructural changes in the early state.In the present study,we provided an integrated approach to investigate e... Objectives It is not fully clarified how diabetes mellitus induced cardiac dysfunction and myocardial ultrastructural changes in the early state.In the present study,we provided an integrated approach to investigate early changes in myocardial function of diabetic rabbits and assessed the structural alteration.Methods and Results Diabetes was induced by alloxan injection.After 30 days,echocardio- graphy and left ventricular cannulation were performed in dia- betic(D,n=8) and control rabbits(C,n= 10).After catheterization, animals were killed for histological studies.Hema-toxylin -eosin and Masson’s Trichrome staining of the heart were analyzed.The ultrastructure of left ventricle was also examined with electron microscopy.Echocardiography revealed that early diabetic cardiomyopathy had impaired LV diastolic function expressed by diminished E-waves,increased Awaves, E/A ratio reversion and increased E-wave deceleration time(EDT).Concurrently,LV end-diastolic pressure(LVEDP) and diastolic time constant(T) were increased,minimum dP/ dt(LV-dp/dt)was reduced,obtained through cardiac catheterization.There were no significant differences in LV ejection fraction(EF),LV peak systolic pressure(LVSP), or maximum dP/dt(LV + dp/dt).Qualitative light microscopy revealed no histologic changes in myocardium from diabetic rabbits.The most evident ultrastructural change was spotted myofibrillar damage,while interstitial fibrosis was slight.Conclusions These results suggest that early diabetic cardiomyopathy in animal model is characterized by left ventricular diastolic dysfunction,both impaired active relaxation and increased passive chamber stiffness.Whereas,left ventricular systolic function can remain normal.It might partly contribute to myofibrillar damage,but not myocardial fibrosis. 展开更多
关键词 Cardiac functional and ultrastructural changes in early diabetic cardiomyopathy rabbits
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Dynamic changes of cellular immune function and individualized adjustments of immunosup-pressant for the management of severe infection after liver transplantation
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作者 李瑞东 《外科研究与新技术》 2011年第4期276-276,共1页
Objective To explore the dynamic changes of the cellular immune function in severe infection after liver transplantation,and to guide the individualized immunology adjustment. Methods 378 cases of liver transplantatio... Objective To explore the dynamic changes of the cellular immune function in severe infection after liver transplantation,and to guide the individualized immunology adjustment. Methods 378 cases of liver transplantation were analyzed retrospectively. Seventy - four cases ( infection group) suffered serious infection,including 54 cases cured ( cure group) ,20 cases died ( 展开更多
关键词 than Dynamic changes of cellular immune function and individualized adjustments of immunosup-pressant for the management of severe infection after liver transplantation
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The Glacier Area Changes in the Qangtang Plateau Based on the Multi-temporal Grid Method and its Sensitivity to Climate Change 被引量:5
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作者 WANG Liping XIE Zichu +3 位作者 WANG Xin LIU Shiyin DING Liangfu SHANGGUAN Donghui 《Journal of Mountain Science》 SCIE CSCD 2011年第6期882-893,共12页
Glacier area changes in the Qangtang Plateau are analyzed during 1970-2000 using air photos,relevant photogrammetric maps and satellite images based on the multi-temporal grid method.The results indicate that the melt... Glacier area changes in the Qangtang Plateau are analyzed during 1970-2000 using air photos,relevant photogrammetric maps and satellite images based on the multi-temporal grid method.The results indicate that the melting of glaciers accelerated,only a few of glaciers in an advancing state during 1970-2000 in the whole Qangtang Plateau.However,the glaciers seemed still more stable in the study area than in most areas of western China.We estimate that glacier retreat was likely due to air temperature warming during 1970-2000 in the Qangtang Plateau.Furthermore,the functional model of glacier system is applied to study climate sensitivity of glacier area changes,which indicates that glacier lifespan mainly depends on the heating rate,secondly the precipitation,and precipitation increasing can slow down glacier retreat and make glacier lifespan prolonged. 展开更多
关键词 The Qangtang Plateau Glacier change MULTI-TEMPORAL Climate change functional model ofglacier system Simulation
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Time-Temperature Charge Function of a High Dynamic Thermal Heat Storage with Phase Change Material 被引量:1
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作者 Johannes Goeke Andreas Henne 《Energy and Power Engineering》 2015年第2期41-54,共14页
A thermal heat storage system with an energy content of 40 kWh and a temperature of 58°C will be presented. This storage system is suitable for supporting the use of renewable energies in buildings and for absorb... A thermal heat storage system with an energy content of 40 kWh and a temperature of 58°C will be presented. This storage system is suitable for supporting the use of renewable energies in buildings and for absorbing solar heat, heat from co-generation and heat pumps or electric heat from excess wind and solar power. The storage system is equipped with a plate heat exchanger that is so powerful that even with small temperature differences between the flow temperature and the storage temperature a high load dynamic is achieved. The storage system has a performance of 2.8 kW at 4 K and 10.6 kW at a temperature difference of 10 K. Thus, large performance variations in solar thermal systems or CHP plants can be buffered very well. Further a storage charge function Q(T, t) will be presented to characterize the performance of the storage. 展开更多
关键词 THERMAL STORAGE Phase change Material (PCM) Plate Heat EXchangER Dynamic Performance STORAGE CHARGE function
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Developmental and Condition-Related Changes in the Prefrontal Cortex Activity during Rest 被引量:1
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作者 Ling-Yin Liang Jia-Jin Jason Chen +1 位作者 Patricia A. Shewokis Nancy Getchell 《Journal of Behavioral and Brain Science》 2016年第12期485-497,共13页
The prefrontal cortex (PFC) plays an important role in cognitive process related to executive function, but is also active during resting states. Quantifying prefrontal cortex activity during resting states provides a... The prefrontal cortex (PFC) plays an important role in cognitive process related to executive function, but is also active during resting states. Quantifying prefrontal cortex activity during resting states provides a baseline for interpreting task-induced brain activity. Researchers commonly use resting conditions where participants are prompted to stare at a screen (eyes open) or close their eyes (eyes closed). Are these two conditions equivalent representations of a baseline resting state? Further, does prefrontal cortex activity during these conditions change as a function of development? The aim of this study was to examine differences in prefrontal cortex activity between eyes open and eyes closed conditions during resting states in children and adults to provide a rationale of proper selection of baseline condition in future research. Thirty-six participants in 3 age groups were recruited in this study including twenty-four adults, five 12 - 15 years old children, and seven 8 - 11 years old children. Relative changes in concentrations of oxygenated hemoglobin (Δoxy-Hb) and deoxygenated hemoglobin (Δdeoxy-Hb) were obtained by using functional Near-Infrared Spectroscopy (fNIRS) in eyes closed (EC) and eyes open (EO) conditions, 3 minutes each. Contrasts were tested to compare the differences of Δoxy-Hb and Δdeoxy-Hb between eyes open and eyes closed conditions. The EC condition had significantly higher Δoxy-Hb than EO when all groups were combined (t (17.268) = 3.021, p = .008, Cohen’s d = –0.72). When comparing Δoxy-Hb between eyes conditions within each group, the younger group had significantly higher Δoxy-Hb in EC than EO (t (9.459) = 2.734, p = 0.022, Cohen’s d = –1.46). Based on these results, the EO condition may be a better baseline condition, particularly in studies with younger children, since it has less activity in the PFC that could interfere with interpretations of task-induced activity. 展开更多
关键词 functional Near-Infrared Spectroscopy (fNIRS) Developmental changes Resting Conditions Eyes Open (EO) Eyes Closed (EC)
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Assessing Density Functionals for Describing Methane Dissociative Chemisorption on Pt(110)-(2×1)Surface 被引量:1
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作者 Fenfei Wei Egidius W.F.Smeets +3 位作者 Johannes Voss Geert-Jan Kroes Sen Lin Hua Guo 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2021年第6期883-895,I0004,共14页
In this work,we explore the suitability of several density functionals with the generalized gradient approximation(GGA)and beyond for describing the dissociative chemisorption of methane on the reconstructed Pt(110)-(... In this work,we explore the suitability of several density functionals with the generalized gradient approximation(GGA)and beyond for describing the dissociative chemisorption of methane on the reconstructed Pt(110)-(2×1)surface.The bulk and surface structures of the metal,methane adsorption energy,and dissociation barrier are used to assess the functionals.A van der Waals corrected GGA functional(optPBE-vdW)and a metaGGA functional with van der Waals correction(MS PBEl-rVV10)are selected for ab initio molecular dynamics calculations of the sticking probability.Our results suggest that the use of these two functionals may lead to a better agreement with existing experimental results,thus serving as a good starting point for future development of reliable machine-learned potential energy surfaces for the dissociation of methane on the Pt(110)-(2×1)surface. 展开更多
关键词 functionalS METHANE DISSOCIATION Pt(110)-(2×1)
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Interaction of Photoactive[Fe(CN)_6]^(4-) with TiO_2 Anatase(101) Surface:A Periodic Density Functional Theory Study 被引量:2
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作者 XU Ying CHEN Wen-Kai CAO Mei-Juan LIU Shu-Hong LI Jun-Qian 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2007年第3期361-366,共6页
The plane-wave pseudopotential function method, based on density-functional theory, has been used to calculate the adsorption, electronic band structures, orbitals and optical absorption spectrum of [Fe(CN)6]^4- on ... The plane-wave pseudopotential function method, based on density-functional theory, has been used to calculate the adsorption, electronic band structures, orbitals and optical absorption spectrum of [Fe(CN)6]^4- on TiOz anatase(101) surface. Our calculations reveal that the surface-modified anatase system has large adsorption energy and a much narrower band gap. [Fe(CN)6]^4- adsorption on the (101) surface could lead to a large red shift of the anatase optical absorption threshold, which extends into a visible region significantly. The calculated results are in agreement with the experiment and other theoretical studies reasonably. It is very important for the understanding and further development ofphotovoltaic materials that are active under visible light. 展开更多
关键词 density functional theory (DFT) [Fe(CN)6]^4- anatase(101) surface adsorption absorption
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Effects of naloxone hydrochloride on pulmonary function, blood gas changes and inflammatory factors in patients with COPD combined with respiratory failure 被引量:1
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作者 Juan Wu Jun Wang Yi Zhang 《Journal of Hainan Medical University》 2017年第22期37-40,共4页
Objective: To investigate the effects of naloxone hydrochloride on pulmonary function, blood gas changes and inflammatory factors in patients with COPD combined with respiratory failure. Methods: According to random d... Objective: To investigate the effects of naloxone hydrochloride on pulmonary function, blood gas changes and inflammatory factors in patients with COPD combined with respiratory failure. Methods: According to random data table method, 80 cases of COPD combined with respiratory failure were randomly divided into the control group (n=40) and observation group (n=40), patients in the control group were treated with noninvasive positive pressure ventilation on the basis of routine symptomatic treatment, on the basis of the treatment of the control group, the observation group received naloxone hydrochloride therapy. The levels of pulmonary function, blood gas changes and inflammatory factors were compared in two groups before and after treatment. Results: The levels of serum FEV1, FVC, PEF, PaCO2, PaO2, PaO2/FiO2, TNF-α and PCT in the two groups before treatment were not statistically significant. After treatment, the levels of FEV1, FVC, PEF in the control group and observation group were (70.01±0.36)%, (2.16±0.41) L, (2.98±0.45) L/s and (81.71±0.53)%, (3.65±0.55) L, (4.36±0.43) L/s, which were significantly higher than those in the same group before treatment, and the levels in observation group were significantly higher than those in the control group;the levels of PaCO2, PaO2 and PaO22/FiO2 in the two groups were (59.62±6.47) mmHg, (65.53±7.36) mmHg, (323.89±10.47) and (46.59±6.64) mmHg, (73.65±8.26) mmHg, (398.64±14.06), compared with the same group before treatment, PaCO2 levels were significantly lower in both groups, and the observation group was significantly lower than the control group, PaO2,PaO2/FiO2 levels were significantly increased in both groups, and the observation group was significantly higher than the control group;the levels of TNF-α, PCT in the two groups were (23.28±4.53) pg/mL, (5.22±2.13) ng/mL and (16.61±4.12) pg/mL, (2.07±1.21) ng/mL, which were significantly lower than those in the same group before treatment, moreover, the observation group levels were significantly lower than those in the control group. Conclusion:Treatment of COPD with respiratory failure by naloxone hydrochloride can effectively reduce the level of inflammatory factors, and improved lung function and blood gas levels, which has important clinical value. 展开更多
关键词 NALOXONE HYDROCHLORIDE COPD COMBINED with RESPIRATORY failure Pulmonary function Blood gas changes INFLAMMATORY factors
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