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During the development of visual cortex, the structure of neurons will adaptively change and adjust according to the changes of external environment, which shows structural plasticity.The experience-dependent plasticity of visual cortex is based on the structural changes of neurons, which mainly include change of synaptic connections, disappearance or increase of dendritic spines, turnover of dendritic spines, changes in the size of dendritic spines, changes in postsynaptic density and alterations of perineuronal nets.The structural changes of neurons have significant influence on the plasticity of visual cortex function and structure, and are highly associated with some molecules or non-neuronal components such as paired immunoglobulin-like receptor B, Ly-6/neurotoxin-like protein 1, Nogo, microglia and extracellular matrix and so on.In addition, external intervention factors such as abnormal visual experience and environmental enrichment can have significant impact on the regulation of the structural changes of neurons, and finally influence the development of visual function and the recovery from visual impairment.In comparison with the functional studies, studies on the structural plasticity of visual cortical neurons depend on the state-of-the-art imaging techniques at cellular or sub-cellular level with more visualizable and convincing results.The constant exploration of the structural plasticity of visual cortex will enhance our understanding of visual development-related diseases, such as amblyopia, and lay the foundation for related basic research and innovative treatments.Advances in the structural plasticity of visual cortex were reviewed in this article.
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Objective:To evaluate the changes in subfoveal choroidal thickness (SFCT) in amblyopic eyes.Methods:A evidence-based medicine study. Chinese and English as search terms for amblyopia and choroid was used to search literature in Wanfang, CNKI, and PubMed of National Library of Medicine. Incomplete or irrelevant literature and review literature were excluded. The literature was meta-analyzed using STATA 15.0. The weighted mean difference (WMD) and 95% confidence interval ( CI) were selected as the estimated value of effect size, and subgroup analysis and sensitivity analysis were used to detect the source of heterogeneity. Results:According to the search strategy, 75 articles were initially retrieved, and 15 articles were finally included for meta-analysis. A total of 650 patients with amblyopia, aged 3 to 65 years old, were included. The enhanced depth imaging technology of spectral domain optical coherence tomography was used to measure SFCT. The results of meta analysis showed that SFCT of amblyopic eyes was more effective than the contralateral eye (WMD=18.89 μm, 95% CI 14.81-22.98 μm, P<0.001) and normal eyes were thicken (WMD=39.49 μm, 95% CI 33.88-45.09 μm, P<0.001). There was no statistically significant difference in SFCT between anisometropic and strabismic amblyopia eyes (WMD=-5.03 μm, 95% CI -19.50-9.44 μm, P=0.495). Conclusions:The SFCT of amblyopic eyes in amblyopic patients is thicker than that of the contralateral eye and normal eyes. There is no difference in SFCT between anisometropia and strabismus amblyopia.
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Objective:To master the changes of Kashin-Beck disease and the examination and acceptance in Zhalantun City, and to provide scientific basis for formulating prevention and control strategies of Kashin-Beck disease.Methods:From 2016 to 2017, in each county under the jurisdiction of Zhalantun City, 5 townships affected by the disease were selected, 3 villages were selected from each township, and the prevalence of Kashin-Beck disease of all residential children aged 7 to 12 years who lived in the villages for more than 6 months were investigated. The clinical and X-ray diagnosis were performed according to the "Diagnosis of Kashin-Beck Disease" (WS/T 207-2010) standard, and the prevalence of Kashin-Beck disease in children aged 7 to 12 years in Zhalantun City in 2016 and 2017 were compared. In accordance with the "Key Endemic Disease Control and Elimination Evaluation Measures" ([2014]79), the condition of Kashin-Beck disease and the implementation of its prevention and control measures was assessed.Results:From 2016 to 2017, 1 697 children aged 7 to 12 years were examined, there were no clinical cases of Kashin-Beck disease and 11 cases of X-ray positive changes. Among them, 844 children were examined in 2016, the positive rate of X-ray was 0.24% (2/844), the positive rate of metaphyseal was 0.24% (2/844), and no positive changes of extremities and triad were detected. A total of 853 children were examined in 2017, the positive rate of X-ray was 1.06% (9/853), the positive rate of metaphyseal was 1.06% (9/853), and no positive changes of extremities and triad were detected. The positive rate of X-ray and metaphyseal of Kashin-Beck disease in children aged 7 - 12 years in 2017 were higher than those in 2016 (χ 2 = 4.409, 4.409, P < 0.05). All surveyed villages had reached the national elimination standard (no clinical cases for children aged 7 - 12 years, X-ray positive rate ≤3% and no cases of hand bone end changes); the organization management scores of Kashin-Beck disease prevention and treatment in Zhalantun City in 2016 and 2017 were 88 points, reaching the qualified standard ( > 85 points). Conclusion:The condition of Kashin-Beck disease in Zhalantun City has reached the standard of elimination, which lays a foundation for further comprehensive elimination of Kaschin-Beck disease in Hulunbuir City.
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Background The characteristics of eye movement waveforms in congenital nystagmus eyes is so complicated that the time-series waveform can hardly demonstrate the oscillational kinetic property of the eye movement of nystagmus,which is not convenient for the clinical diagnosis and evaluation.The eye movement system is a nonlinear feedback control system,and phase portrait analysis is a useful method in describing the characteristics of movement in a nonlinear system.Objective This study was to establish the phase portrait analysis method of the eye movement waveforms in congenital nystagmus eyes and provide a new technique for the clinical diagnosis and evaluation of congenital nystagmus.Methods A prospective series-case observational study was performed.This study complied with the Declaration of Helsinki and was approved by Ethic Commission of Tianjin Eye Hospital.Written informed consent was obtained from each patient before examination.Twenty-five patients with congenital nystagmus were enrolled and received examination of video-oculography (VOG) in Tianjin Eye Hospital from April 2012 to February 2013,including 12 patients with congenital motor nystagmus (CMN) and 13 patients with latent nystagmus (LN).The VOG data were format-converted and processed by a Matlab routine.VOG-based phase portraits of eye movement cycles were drawn and related parameters were measured from the phase portraits for further analysis and comparison.Main measurement indexes were cycle position shift (CPS),slow phase peak velocity (SPV),standardized slow-phase peak (SSPV),fast phase peak velocity (FPV) and standardized fast-phase peak velocity (SFPV).Two principal types of waveforms,increasing-velocity type and decreasing-velocity type were compared.Results The phase portraits of the waveforms of congenital nystagmus were cycles of reciprocating trajectories.The slow phases were in dense ribbon region,and the fast phases were in sparse annular region,and all the trajectories travelled in clockwise.The CPS,SPV and FPV of increasing-velocity type were (4.646 ± 1.565),(223.821 ± 114.049),(767.481 ±263.560) ° per second,respectively.The CPS,SPV and FPV of decreasing-velocity type were (9.373 ±4.189),(357.531 ± 154.300) and (1 148.706 ±541.362) ° per second,respectively.The SPVs and FPVs of both increasing-velocity type and decreasing-velocity type showed strong correlation with CPS,respectively (the increasing-velocity type:rSPV-CPS =0.685,P=0.000;rFPV-CPS =0.680,P=0.000;the decreasing-velocity type rSPV-CPS =0.783,P =0.000;rFPV-CPS =0.803,P =0.000).FPVs were significantly larger than SPVs in both types of waveforms (t =6.558,P =0.000;t =5.068,P =0.000).The SSPV of increasing-velocity type was (48.062 ± 15.365) ° per second,which was slightly larger than (41.099± 17.027) ° per second of decreasing-velocity type,with no significant difference between them (t=1.070,P=0.296).The SFPV of increasing-velocity type was (171.186±47.825)° per second,which was larger than (125.317-±38.266)° per second of decreasing-velocity type,showing a significant difference between them (t =2.658,P =0.014).Conclusions Phase portraits can visualize the cyclically dynamic features of congenital nystagmus in a direct way.It facilitates the measurement of eye movement amplitude,speed and other parameters.The phase portrait analysis method provides a novel useful tool in the clinical diagnosis and treatment efficacy evaluation of congenital nystagmus.
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Background The visual development is completed during the critical period in human and mammals.However,the critical period is not the initial of receiving visual experience.It is known that before the onset of critical period in mammals,such as mouse,there is an earlier stage for visual development,the pre-critical period.The research of response characteristics of the visual cortical neurons and the synaptic plasticity in the pre-critical period is still in the exploratory stage.Objective The study aimed to preliminarily investigate the response properties of neurons and synaptic plasticity in mouse visual cortex during the pre-critical period.Methods Fortyeight postnatal day 13-17 C57BL/6J mice were used for in vivo whole-cell recordings and in vitro brain slice wholecell recordings.In vivo whole-cell recordings were done in anesthetized mice.Moving bars in different directions were produced and controlled by a Matlab program.Cell recordings were obtained at the depth of layer Ⅳ of visual cortex.Step current stimuli under current clamp were given to measure the membrane response properties of neurons.Optimal visual stimuli were given to measure the in vivo largest responses of membrane potentials.In vitro experiments were performed after in vivo experiments.All cells were given current step stimuli to measure the membrane response properties of neurons.Different intensities of white-matter-to-layer-Ⅳpathway stimulation were given to measure the evoked response properties.All cells from 48 mice were randomized into 4 groups according to different stimulus training modes,including low frequency stimulation (LFS),high frequency theta-burst stimulation (TBS),pre-post synaptic timing stimulation (pre-post TS) and post-pre synaptic timing stimulation (post-pre TS).Under the voltage clamp of-70 mV,excitatory postsynaptic currents (EPSCs) before and after training were recorded to measure the plastic changes of excitatory synaptic connections.pClamp 10 was used for the pre-analysis of data and Matlab 2008a was used for statistical analysis.The use and care of the animals followed the Statement for the Use of Animals in Ophthalmic and Vision Research.Results Thirty-nine cells and 48 cells were successfully recorded in the in vivo and in vitro experiments,respectively.The steady-state average number of action potentials (APs) were (1.01 ± 0.03)/sweep and (1.01 ±0.05)/sweep,the AP thresholds were (-40.2 ± 3.2) mV and (-39.6 ±2.0) mV,and the threshold step current levels were (126.7 ± 17.4) pA and (129.6 ± 17.5) pA in the in vivo and in vitro recordings,respectively,with no significant differences between them (APs:t =0.512,P =0.610;AP thresholds:t =-1.074,P =0.286;current levels:t =-0.776,P =0.440).Under the optimal visual or pathway stimulation,the average peak response of membrane potentials was (7.3 ±4.3)mV and (6.4±2.8)mV with rarely evoked APs in the in vivo and in vitro experiments,respectively,with no significant difference between them (t =1.234,P =0.221).Under the in vitro recording,the EPSCs before LFS were [(138.1 ±51.9)pA],which was significantly higher than that after LFS [(76.1 ± 34.8)pA] (t=4.437,P=0.001),but no significant differences were seen in EPSCs before and after TBS (t=-0.756,P=0.466).The EPSCs before and after pre-post TS were (122.4±62.2)pA and (78.5±46.7)pA,and those before and after post-pre TS were (131.9 ±48.0) pA and (74.3 ± 30.7) pA,showing significant differences between them (pre-post TS:t =3.558,P =0.004;post-pre TS:t =4.283,P =0.001).Conclusions The construction of fundamental neural circuits in layer Ⅳ of mouse visual cortex is completed during pre-critical period.However,the membrane responsive capability of neurons and the synaptic connections are in an immature state,and the evoked responses to visual pathway inputs are basically subthreshold.The strength of synaptic connections is depressed with low frequency stimulation or pre-post/post-pre synaptic timing stimulation,and kept unchanged with high frequency stimulation.The development of visual neural system of PSP in mouse presents different characteristics from CP.
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Objective To evaluate the promotional effectiveness of different TCM appropriate technology packages; To provide a scientific basis for improving the technology package. Methods 8 assessment indexes, including input costs, the number of experts, the number of people with senior professional post, the number of grassroots people under the guidance of experts, the number of training hours, the number of people receiving training, evaluating rate and the number of users were selected. TOPSIS method was used to evaluate the promotional effectiveness of five kinds of TCM packages in grassroots. Results The Ci values for appropriate technology packages were 0.76 for pains in neck, shoulder, waist and lower extremities, 0.49 for gynecological diseases, 0.44 for infantile diarrhea, 0.66 for chronic gastropathy, and 0.00 for tumors. Conclusion The effectiveness of promotion of TCM appropriate technology packages from high to low is pains in neck, shoulder, waist and lower extremities package, chronic gastropathy package, gynecological diseases package, infantile diarrhea package, tumors package.
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BACKGROUND:Femoral neck fracture is mainly fixed by three inverted triangle cannulated screws. Scholars have proposed to add a cannulated screw to enhance the fixation strength of femoral neck fracture of Pauwels III type based on three cannulated screw fixation, but the stability is not verified. OBJECTIVE:To analyze the biomechanical stability and stress of the three and four cannulated screws for the treatment of the Pauwels III femoral neck fractures. METHODS:The CT imaging results of the fourth generation of artificial bone sawbones were imported into the Mimics software wherein a three-dimensional finite element model of the proximal femur was prepared and introduced in the 3-matic software. Models of middlesegment of femoral neck with Pauwels III fractures were established. Cannulated screw models were established with UG 8.0 software and introduced in the fractures models. Finally, finite element models of Pauwels III femoral neck fractures fixed with three and four screws were established. In the same condition, an axial load of 411 N was applied on the femoral head with Abaqus software. The displacement of two markers of the broken ends and internal fixation system Von Mises stress distribution were compared between the two models. RESULTS AND CONCLUSION:(1) The displacement was 0.42 mm in three screws model, and 0.17 mm in the four screws model. (2) Von Mises stress peak was 547 MPa and 27.8 MPa in both models. The peak value was lower in models of fourscrews than that of three screws. Stress concentration position was at the fracture site in both models. The stress range of models of four screws was more extensive and scattered. (3) Finite element analysis results demonstrated that four-screw implantation for Pauwels III femoral neck fractures had strong anti-shearing force and biomechanical stability. Clinical advantages need further clinical comparative study.
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Objective To investigate the clinical utility of keyhole craniotomy for Cholesteatmas in the cerebello-pontine angle region presenting as Trigeminal neuralgia by using keyhole craniotomy. Methods Clinical data of 35 pa-tients with Cholesteatmas in the cerebellopontine angle region presenting as Trigeminal neuralgia was analyzed retrospec-tively. All patients received suboccipital retrosigmoid keyhole craniotomy. Thirty cases who received conventional craniot-omy group were served as control group. A comparative analysis was conducted to assess the difference between these two groups in microsurgical methods, effects and complications. Results All patients were confirmed with MR diagnosis. In keyhole group, all patients had no pain symptoms of trigeminal neuralgia after surgical operation. The symptoms disap-peared immediately in 33 cases and gradually disappeared in 2 cases within one month following keyhole craniotomy. The tumors were totally removed in 25 cases and almost completely in 10 cases. The surgical duration was shorten in key-hole group than in conventional group (126±48 vs. 216±66 min;t=2.536, P<0.05). The amount of bleeding was smaller in keyhole group than in conventional group (91.3±52.2 vs. 186.3±65.4 mL;t=2.163, P<0.05). Postoperative neurologi-cal function was assessed in House-Brackmann. In keyhole group, there were 32 cases in class Ⅰ and 3 in grade Ⅱ. Two patients had hearing loss which was improved gradually in three months. In conventional group, there were 25 cases in class Ⅰ and 5 in grade Ⅱ (χ2=4.158, P<0.05). Postoperative hearing evaluation (AAO-HNS) revealed that there were 33 cases in grade A , and 2 in grade B in the keyhole group, whereas there were 27 cases in grade A and 3 in grade B in the conventional group(χ2=5.167, P<0.05). There were no relapse of tumors and death during 3 month to 5 years follow-up. Conclusions The suboccipital retrosigmoid keyhole craniotomy is a valid choice for Cholesteatmas in the cerebellopontine angle region presenting as Trigeminal neuralgia.
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Background EyeLink 2000 high speed video eye tracker has been used in ophthalmology to evaluate the ocular movement ability.Its systemic precision depends on the performance of the eye tracker, and it is also an essential parameter for the evaluation of the data quality.Therefore, the impact of infrared intensity should be illustrated.Objective This study was to assess the systemic precision of the video eye tracker and evaluate the impact of infrared intensity on the result.Methods The EyeLink 2000 high speed video eye tracker and a pair of artificial eyes were used in this study.Firstly the artificial eyes were fixed to the corresponding position as the real human eyes.Each session of recording was undertaken under the different infrared intensities (100％ , 75％ and 50％).The sampling frequency of binocular recording was set as 1 000 Hz.Each session was sequentially recorded for 60 seconds.The systemic precision was calculated as the root mean square (RMS) of angular distances between successive data points.The RMS values under the different infrared intensities were compared.Results The highest RMS values were (0.005 01 ± 0.000 20) ° under the 100％ infrared intensity.As the decline of infrared intensities ,RMS values were gradually raised, showing a significant difference among different infrared intensity groups (F =3 791.447, P＜0.01).The differences were also significant between different groups (all at P＜0.05).Conclusions EyeLink 2 000 video eye tracker has good system precision.The infrared intensity influence the system precision of the video eye tracker.
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Objective To study the relevance between the level of thyroid hormone and anti‐thyroid peroxidase antibody (TPOAb) during gestation period .Methods From November 2011 to May 2014 ,150 gravidas were chosen as objectives ,and were divided into 2 groups according TPOAb .The clinical feature ,level of thyroid hormone ,pregnancy outcome ,and complication of neo‐phyte between 2 groups were compared .Results In 150 gravidas ,44 were positive in TPOAb and 106 were negative .The age ,ges‐tational weeks and BMI between two groups had no statistical difference(P>0 .05) .At the early and middle pregnancy as well as at the late pregnancy ,the level of thyroid hormone between two groups had statistical difference(P<0 .05);In study group ,the level of thyroid hormone of early and middle pregnancy and that of late pregnancy had statistical difference(P<0 .05) .The rate of unde‐sirable gestational outcome and that of neophyte complication between two groups had statistical difference(P<0 .05) .Conclusion During gestation period ,the TPOAb was significant for the diagnosis of the sub‐clinical hypothyroidism ,as well for prognosis of gravidas .
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Seven guaiane-type sesquiterpenoids, a new compound 6-formyl-5-isopropyl-3-hydroxymethyl-7-methyl-1H-indene (1), a new natural product 5-isopropyl-3, 7-dimethyl-1H-indene-1-one (2), along with five known compounds: guaiazulene (3), 4-formyl-7-isopropyl-10-methylazulene (4), sesquiterpene ketolactone (5), alismoxide (6) and guaia-1 (5), 6-diene (7), were isolated from gorgonian Muriceides collaris collected in South China Sea. Their structures were elucidated on the basis of extensive spectroscopic analysis [MS, IR, 1H NMR, 13C NMR (DEPT), HMQC, HMBC, NOESY] and by comparison of the spectral data with those of the literatures.
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Foreign specialist physician system has been implemented for more than 100 years. China piloted its own specialist physician system from 2004. The article compared foreign specialist physician system with China’s pilot system. Combined with TCM clinical characteristics and laws, the article also discussed to set up Chinese medical specialist system which is in accordance with both international conventions and TCM laws of development as well as docking the pilot system.
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OBJECTIVE:To study the bioequivalence of the domestic and the imported mycophenolate mofetil capsules in human body.METHODS:A single dose of 1 000mg domestic mycophenolate mofetil capsules(trial)or its reference capsule(imported ones)were given to each volunteer in a randomized double cross-over design.The plasma concentration was determined by RP-HPLC.The pharmacokinetic parameters of two preparations were calculated and the bioequivalence of which was evaluated.RESULTS:The main pharmacokinetic parameter of the trial vs.the reference preparations of mycophenolate mofetil capsules were as follows:Cmax:(26.38?9.55)versus(25.84?12.08)?g?mL-1;tmax:(0.79?0.40)h versus(0.94?0.59)h;t1/2:(18.01?7.65)h versus(15.62?8.50)h;AUC0～48:(54.69?15.58)versus(51.68?12.36)?g?h?mL-1;AUC0～∞:(61.10?17.06)versus(57.99?17.21)?g?h?mL-1.The relative bioavailability of the trial preparation was(107.22?25.39)%.CONCLUSION:The results suggest that the two formulations are bioequivalent.
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Objective To investigate the chemical constituents of gorgonian Muriceides collaris. Methods The compounds were isolated and purified by silica gel column,Sephadex LH-20 column chromatography and HPLC. Their chemical structures were identified by physicochemical analysis,spectroscopic analysis,and comparison with the data of literatures. Results From the CH3OH soluble extract of Muriceides collaris,nine compounds were isolated,and their structures were determined as cholesterol (1),batyl alcohol (2),benzoic acid (3),uracil (4),thymine (5),2'-deoxyuridine (6),2'-deoxythymidine (7),thymidine (8) and 2'-deoxyadenosine (9),respectively. Conclusion All compounds were obtained from the species Muriceides collaris for the first time.