The Extensible Markup Language(XML)files,widely used for storing and exchanging information on the web require efficient parsing mechanisms to improve the performance of the applications.With the existing Document Obj...The Extensible Markup Language(XML)files,widely used for storing and exchanging information on the web require efficient parsing mechanisms to improve the performance of the applications.With the existing Document Object Model(DOM)based parsing,the performance degrades due to sequential processing and large memory requirements,thereby requiring an efficient XML parser to mitigate these issues.In this paper,we propose a Parallel XML Tree Generator(PXTG)algorithm for accelerating the parsing of XML files and a Regression-based XML Parsing Framework(RXPF)that analyzes and predicts performance through profiling,regression,and code generation for efficient parsing.The PXTG algorithm is based on dividing the XML file into n parts and producing n trees in parallel.The profiling phase of the RXPF framework produces a dataset by measuring the performance of various parsing models including StAX,SAX,DOM,JDOM,and PXTG on different cores by using multiple file sizes.The regression phase produces the prediction model,based on which the final code for efficient parsing of XML files is produced through the code generation phase.The RXPF framework has shown a significant improvement in performance varying from 9.54%to 32.34%over other existing models used for parsing XML files.展开更多
In this paper, we present a modular incremental statistical model for English full parsing. Unlike other full parsing approaches in which the analysis of the sentence is a uniform process, our model separates the full...In this paper, we present a modular incremental statistical model for English full parsing. Unlike other full parsing approaches in which the analysis of the sentence is a uniform process, our model separates the full parsing into shallow parsing and sentence skeleton parsing. In shallow parsing, we finish POS tagging, Base NP identification, prepositional phrase attachment and subordinate clause identification. In skeleton parsing, we use a layered feature-oriented statistical method. Modularity possesses the advantage of solving different problems in parsing with corresponding mechanisms. Feature-oriented rule is able to express the complex lingual phenomena at the key point if needed. Evaluated on Penn Treebank corpus, we obtained 89.2% precision and 89.8% recall.展开更多
AIM: To compare the postoperative visual acuity among eyes with proliferative diabetic retinopathy(PDR) of different stages after pars plana vitrectomy(PPV) in type 2 diabetic patients. METHODS: A retrospective study ...AIM: To compare the postoperative visual acuity among eyes with proliferative diabetic retinopathy(PDR) of different stages after pars plana vitrectomy(PPV) in type 2 diabetic patients. METHODS: A retrospective study was conducted for PDR eyes undergoing PPV in type 2 diabetic patients. All patients were divided into three groups based on Chinese Ocular Fundus Diseases Society(COFDS) classification for PDR: Group A(primary vitreous hemorrhage), Group B(primary fibrovascular proliferation) and Group C(primary vitreous hemorrhage and/or fibrovascular proliferative combined with retinal detachment). The postoperative visual acuity and the change between postoperative and preoperative visual acuity were compared among three groups. The associated risk factors for postoperative visual acuity were analyzed in the univariate and multiple linear aggression. RESULTS: In total, 195 eyes of 195 patients were collected in this study, including 71 eyes of 71 patients in Group A, 75 eyes of 75 patients in Group B and 49 eyes of 49 patients in Group C. The eyes in Group A got better postoperative best-corrected visual acuity(BCVA) compared to the eyes in Group B and C(0.48±0.48 vs 0.89±0.63, P<0.001;0.48±0.48 vs 1.04±0.67, P<0.001;respectively). The eyes in Group A got more improvement of BCVA compared to the eyes in Group B and C(1.07±0.70 vs 0.73±0.68, P=0.004;1.07±0.70 vs 0.77±0.78, P=0.024;respectively). In the multiple linear regression analysis, primary fibro-proliferative type(β=0.194, 95%CI=0.060-0.447, P=0.01), retinal detachment type(β=0.244, 95%CI=0.132-0.579, P=0.02), baseline log MAR BCVA(β=0.192, 95%CI=0.068-0.345, P=0.004), silicone oil tamponade(β=0.272, 95%CI=0.173-0.528, P<0.001) was positively correlated with postoperative log MAR BCVA. Eyes undergoing phacovitrectomy had better postoperative BCVA(β=-0.144, 95%CI=-0.389 to-0.027, P=0.025). CONCLUSION: PDR eyes of primary vitreous hemorrhage type usually have better visual acuity prognosis compared to primary fibrovascular proliferation type and retinal detachment type. COFDS classification for PDR may have a high prognostic value for postoperative visual outcome and surgical management indications.展开更多
Because neurons are susceptible to oxidative damage and thioredoxin reductase 1 is extensively distributed in the central nervous system and has antioxidant properties, we speculated that the enzyme may be involved in...Because neurons are susceptible to oxidative damage and thioredoxin reductase 1 is extensively distributed in the central nervous system and has antioxidant properties, we speculated that the enzyme may be involved in the pathogenesis of Parkinson's disease. A Parkinson's disease model was produced by intraperitoneal injection of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine into C57BL/6 mice. Real-time reverse transcription-PCR, western blot analysis and colorimetric assay showed that the levels of thioredoxin reductase 1 mRNA and protein were decreased, along with a significant reduction in thioredoxin reductase activity, in the midbrain of Parkinson's disease mice compared with normal mice. Immunohistochemical staining revealed that the number of thioredoxin reductase 1-positive neurons in the substantia nigra pars compacta of Parkinson's disease mice was significantly decreased compared with normal mice. These experimental findings suggest that the expression of thioredoxin reductase 1 in the substantia nigra pars compacta of Parkinson's disease mice is significantly decreased, and that the enzyme may be associated with disease onset.展开更多
AIM:To describe the clinical characters of rhegmatogenous retinal detachment(RRD) associated with massive spontaneous suprachoroidal hemorrhage(SSCH). To evaluate optimal timing and prognosis of pars plana vitrectomy....AIM:To describe the clinical characters of rhegmatogenous retinal detachment(RRD) associated with massive spontaneous suprachoroidal hemorrhage(SSCH). To evaluate optimal timing and prognosis of pars plana vitrectomy.METHODS:A retrospective review of 6 cases(6 eyes)of RRD and massive SSCH among 3772 cases of RRD was conducted. All of 6 patients were treated with twenty-gauge vitrectomy, suprachoroidal blood drainage,phacoemulsification(PHACO) or lensectomy and silicon oil tamponade. The clinical characters, intraoperative findings and treatment outcomes were reported.RESULTS:In the 6 affected eyes of 6 patients(3 men and 3 women; mean age, 53.83y; range 34-61y),preoperative visual acuity ranged from faint light perception(LP) to counting finger(CF). The average interventional duration from visual decreased to surgery was 12.8 d(range 9-15d). All eyes were associated with high myopia and the mean ocular length was 30.32 mm(range 28.14-32.32 mm). Choroidal hemorrhage were successfully drained in the operation of all 6 eyes.Intraoperative findings showed there were multiple retinal breaks in all 6 eyes and in 4 eyes breaks were along supratemporal and/or infratemporal retinal vascular arcade, especially in the edge of chorioretinal atrophy areas. These patients were followed up from 6 to 34mo(Mean, 23.5mo). The best-corrected visual acuity after surgery varied from CF to 20/100, with improvement in 5eyes(83.33%) and no change in 1 eye(16.67%). Ocular hypertension ocurred in 1 eye(16.67%), which wassuccessfully treated by silicon oil removal combined with trabeculectomy. In 4 eyes, tractional retinal detachment caused by proliferative vitreoretinopathy(PVR) appeared and a secondary surgery of pre-retinal membrane peeling and silicon oil retained were performed. In 4eyes, silicon oil cannot be removed. The initial and final reattachment rates were 33.33% and 66.67%, respectively.CONCLUSION:RRD associated with massive SSCH is an extremely rare event. The most common risk factor is long axial length. Vitrectomy and choroidal blood drainage can effectively remove suprachoroidal hemorrhage and promote retinal reattachment in these eyes. However, silicon oil could not be removed in most eyes and final visual acuities are generally poor.展开更多
AIMTo evaluate outcomes of combined pars plana vitrectomy and Baerveldt glaucoma implant (PPV-BGI) placement for refractory glaucoma.METHODSThe medical records of 92 eyes (89 patients) that underwent PPV-BGI were retr...AIMTo evaluate outcomes of combined pars plana vitrectomy and Baerveldt glaucoma implant (PPV-BGI) placement for refractory glaucoma.METHODSThe medical records of 92 eyes (89 patients) that underwent PPV-BGI were retrospectively reviewed, including 43 eyes with neovascular glaucoma (NVG) and 49 eyes with other types of glaucoma (non-NVG).RESULTSOutcome measures were visual acuity (VA), intraocular pressure (IOP), glaucoma medical therapy, complications, and success [VA>hand motions (HM), IOP≥6 mm Hg and ≤21 mm Hg, no subsequent glaucoma surgery]. Cumulative success rates for the non-NVG group and NVG group were 79% and 40% at 1y, respectively (P=0.038). No difference in the rates of surgical success were found between pars plana and anterior chamber tube placement. Preoperative IOP (mean±SD) was 30.3±11.7 mm Hg in the Non-NVG group and 40.0±10.6 mm Hg in the NVG group, and IOP was reduced to 15±9.5 mm Hg in the non-NVG group and 15±10.5 mm Hg in the NVG at 1y. Number of glaucoma medications (mean±SD) decreased from 2.7±1.3 in the non-NVG group and 2.8±1.3 in the NVG group preoperatively to 0.76±1.18 in the non-NVG group and 0.51±1.00 in the NVG group at 1y. Improvement in VA of ≥2 Snellen lines was observed in 25 (27%) eyes, although only 33% of non-NVG eyes and 2.3% of NVG eyes maintained VA better than 20/200 at 1y. Nonclearing vitreous hemorrhage was the most common postoperative complication occurring in 16 (17%) eyes, and postoperative suprachoroidal hemorrhages developed in 5 (5.4%) eyes.CONCLUSIONPPV-BGI is a viable surgical option for eyes with refractory glaucoma, but visual outcomes are frequently poor because of ocular comorbidities, especially in eyes with NVG. The location of tube placement does not influence surgical outcome and should be left to the discretion of the surgeon.展开更多
AIM: To report the results of rhegmatogenous retinal detachment(RRD) repair after pars plana vitrectomy(PPV) without operative use of heavy liquid, and utilizing air tamponade in selected cases.METHODS: RRD pati...AIM: To report the results of rhegmatogenous retinal detachment(RRD) repair after pars plana vitrectomy(PPV) without operative use of heavy liquid, and utilizing air tamponade in selected cases.METHODS: RRD patients without severity of proliferative vitreoretinopathy C2 or more underwent PPV without operative use of heavy liquid, and utilizing air tamponade were consecutively enrolled. Alternative postoperative facedown position or lateral position was required for 3-5 d.RESULTS: Totally 36 eyes of 36 patients(24 males, 66.7%) aged 53.8±10.9 y underwent this modified surgery. The mean number of retinal break was 2.1±1.3. Most of the eyes(29, 80.6%) had retinal detachment involving more than one quadrant. Twenty-two(61.1%) eyes with cataract had combined phacoemulsification and intraocular lens implantation. The mean follow up time was 4.6±1.8 mo. Two eyes with retinal redetachment underwent a second retinal repair surgery with silicone oil tamponade, yielding the primary reattachment rate to 94.4%(34/36). Six(16.7%) eyes had intraocular pressure higher than 25 mm Hg. The visual acuity(logMAR) improved from 0.98±0.74 preoperatively to 0.52±0.31 postoperatively(P〈0.001). CONCLUSION: The success rate of this modified retinal repair surgery is comparable with traditional surgery. This technique can be considered for certain retinal detachment patients, since its apparent advantages included lower surgical complications, reduced surgery expenditure, shorter time for postoperative facedown position, and avoiding silicone oil removal surgery.展开更多
Information content security is a branch of cyberspace security. How to effectively manage and use Weibo comment information has become a research focus in the field of information content security. Three main tasks i...Information content security is a branch of cyberspace security. How to effectively manage and use Weibo comment information has become a research focus in the field of information content security. Three main tasks involved are emotion sentence identification and classification,emotion tendency classification,and emotion expression extraction. Combining with the latent Dirichlet allocation(LDA) model,a Gibbs sampling implementation for inference of our algorithm is presented,and can be used to categorize emotion tendency automatically with the computer. In accordance with the lower ratio of recall for emotion expression extraction in Weibo,use dependency parsing,divided into two categories with subject and object,summarized six kinds of dependency models from evaluating objects and emotion words,and proposed that a merge algorithm for evaluating objects can be accurately evaluated by participating in a public bakeoff and in the shared tasks among the best methods in the sub-task of emotion expression extraction,indicating the value of our method as not only innovative but practical.展开更多
AIM:To describe and evaluate the efficacy of Ahmed glaucoma valve implantation(AGV)combined with pars plana vitrectomy(PPV)in a single surgical act for the treatment of advanced neovascular glaucoma(NVG).METHODS:Retro...AIM:To describe and evaluate the efficacy of Ahmed glaucoma valve implantation(AGV)combined with pars plana vitrectomy(PPV)in a single surgical act for the treatment of advanced neovascular glaucoma(NVG).METHODS:Retrospective observational case series included 51 eyes from 50 patients with severe NVG treated with PPV,AGV,and panretinal photocoagulation and/or cryotherapy in a single surgical act during a 13-year period(2005-2018).Preoperative,intraoperative and postoperative data at day 1 and months 1,3,6,21,and 24 were systematically collected.Definition of surgical success was stablished at IOP between 6 and 21 mm Hg with or without topical treatment.RESULTS:Main indications for surgery were NVG secondary to proliferative diabetic retinopathy(39.2%)and central retinal vein occlusion(37.3%).Mean(±SD)preoperative IOP was 42.0±11.2 mm Hg decreasing to 15.5±7.1 mm Hg at 12 mo and 15.8±9.1 mm Hg at 24 mo of follow up.Cumulative incidence of success of IOP control was 76.0%at first postoperative month,reaching 88.3%at 6 mo.Prevalence of successful IOP control at long term was 74.4%at 12 mo and 71.4%at 24 mo.Eye evisceration for unsuccessful NVG management was required in 1 case(2.0%).CONCLUSION:Combination of AGV implantation and PPV in a single act may be a suitable option for severe forms of NVG in a case-by-case basis for effective IOP control and a complete panretinal photocoagulation.展开更多
AIM: To determine the rate and possible contributors for post-pars plana vitrectomy(PPV) epiretinal membrane(ERM) in patients treated for rhegmatogenous retinal detachment(RRD). METHODS: This prospective, nonrandomize...AIM: To determine the rate and possible contributors for post-pars plana vitrectomy(PPV) epiretinal membrane(ERM) in patients treated for rhegmatogenous retinal detachment(RRD). METHODS: This prospective, nonrandomized study comprised 47 consecutive patients(47 eyes) with acute RRD treated with 23 G post-PPV. All participants were followed prospectively for 6 mo for the development of ERM using spectral domain optical coherence tomography. Preoperative and intraoperative data were collected by questionnaires to surgeons. Main outcome measure was the percentage of the ERM formation following post-PPV for RRD. RESULTS: ERM developed postoperatively in 23 eyes(48.9%), none necessitated surgical removal. There was a statistically significant difference between patients with and without ERM postoperatively in preoperative best corrected visual acuity(median log MAR 1.9 vs 0.3, respectively;P=0.003) rate of macula-off(69.6% vs 37.5%, respectively, P=0.028), and rate of ≥5 cryo-applications(55.6% and 18.8%, respectively, P=0.039). ERM developed mainly between the 1st and 3rd months of follow-up. Macula-off status increased the risk of ERM, with the odds ratio of 3.81(P=0.031). CONCLUSION: ERM is a frequent post RRD finding, and its development is associated with macula-off RRD.展开更多
AIM:To compare changes in anterior segment topography and axial length(AL)evaluated with Pentacam and IOL Master after pars plana vitrectomy(PPV)performed with and without vitreous base shaving.METHODS:This prospectiv...AIM:To compare changes in anterior segment topography and axial length(AL)evaluated with Pentacam and IOL Master after pars plana vitrectomy(PPV)performed with and without vitreous base shaving.METHODS:This prospective study included patients who underwent PPV or phacoemulsification+PPV(Phaco+PPV)for various indications.Patients who underwent total posterior hyaloid detachment and excessive vitreous base shaving with scleral indentation were referred to as complete PPV(c-PPV).The patients whom posterior hyaloid was separated as far as the posterior arcades and vitreous base shaving with scleral depression was not performed were classified as the partial PPV(p-PPV)group.All patients underwent detailed ophthalmologic examinations preoperatively and lwk,I,and 3mo postoperatively.Changes in the anterior chamber depth(ACD),anterior chamber volume(ACV),iridocorneal angle(ICA)f central corneal thickness(Cd),and keratometric measurements(K1 and K2)were evaluated with Pentacam HR.Changes in the AL measurements were analyzed with IOL Master.RESULTS:A significant increase in ACD was observed in c-PPV cases(P=0.02),but this increase was not significant in the p-PPV group(P=0.053).In contrast,ICA increased significantly in the c-PPV group(P=0.02)but decreased in the p-PPV group(P=0.09).BCVA was significantly improved in the c-PPV group from week 1(P<0.001)while the increase in the p-PPV group reached significance at 3mo(P=0.035).Cd increased in the first week and later returned to baseline in both groups.No significant differences in the other parameters were observed between the groups,and there were no significant changes in intraocular pressure,ACV,AL,K1 or K2 values(P>0.05 for all).CONCLUSION:Incomplete posterior hyaloid excision and not removing the vitreous base in PPV surgeries may create a more stable anterior chamber,thus preventing the downward movement of the lens-iris diaphragm,and may cause ciliary body retraction,thereby reducing ICA.Awareness of these effects can provide some amount of guidance to physicians in selecting the appropriate PPV procedure and preempting surgical complications.展开更多
Head-driven statistical models for natural language parsing are the most representative lexicalized syntactic parsing models, but they only utilize semantic dependency between words, and do not incorporate other seman...Head-driven statistical models for natural language parsing are the most representative lexicalized syntactic parsing models, but they only utilize semantic dependency between words, and do not incorporate other semantic information such as semantic collocation and semantic category. Some improvements on this distinctive parser are presented. Firstly, "valency" is an essential semantic feature of words. Once the valency of word is determined, the collocation of the word is clear, and the sentence structure can be directly derived. Thus, a syntactic parsing model combining valence structure with semantic dependency is purposed on the base of head-driven statistical syntactic parsing models. Secondly, semantic role labeling(SRL) is very necessary for deep natural language processing. An integrated parsing approach is proposed to integrate semantic parsing into the syntactic parsing process. Experiments are conducted for the refined statistical parser. The results show that 87.12% precision and 85.04% recall are obtained, and F measure is improved by 5.68% compared with the head-driven parsing model introduced by Collins.展开更多
Natural language parsing is a task of great importance and extreme difficulty. In this paper, we present a full Chinese parsing system based on a two-stage approach. Rather than identifying all phrases by a uniform mo...Natural language parsing is a task of great importance and extreme difficulty. In this paper, we present a full Chinese parsing system based on a two-stage approach. Rather than identifying all phrases by a uniform model, we utilize a divide and conquer strategy. We propose an effective and fast method based on Markov model to identify the base phrases. Then we make the first attempt to extend one of the best English parsing models i.e. the head-driven model to recognize Chinese complex phrases. Our two-stage approach is superior to the uniform approach in two aspects. First, it creates synergy between the Markov model and the head-driven model. Second, it reduces the complexity of full Chinese parsing and makes the parsing system space and time efficient. We evaluate our approach in PARSEVAL measures on the open test set, the parsing system performances at 87.53% precision, 87.95% recall.展开更多
This paper proposes a new way to improve the performance of dependency parser: subdividing verbs according to their grammatical functions and integrating the information of verb subclasses into lexicalized parsing mod...This paper proposes a new way to improve the performance of dependency parser: subdividing verbs according to their grammatical functions and integrating the information of verb subclasses into lexicalized parsing model. Firstly,the scheme of verb subdivision is described. Secondly,a maximum entropy model is presented to distinguish verb subclasses. Finally,a statistical parser is developed to evaluate the verb subdivision. Experimental results indicate that the use of verb subclasses has a good influence on parsing performance.展开更多
文摘The Extensible Markup Language(XML)files,widely used for storing and exchanging information on the web require efficient parsing mechanisms to improve the performance of the applications.With the existing Document Object Model(DOM)based parsing,the performance degrades due to sequential processing and large memory requirements,thereby requiring an efficient XML parser to mitigate these issues.In this paper,we propose a Parallel XML Tree Generator(PXTG)algorithm for accelerating the parsing of XML files and a Regression-based XML Parsing Framework(RXPF)that analyzes and predicts performance through profiling,regression,and code generation for efficient parsing.The PXTG algorithm is based on dividing the XML file into n parts and producing n trees in parallel.The profiling phase of the RXPF framework produces a dataset by measuring the performance of various parsing models including StAX,SAX,DOM,JDOM,and PXTG on different cores by using multiple file sizes.The regression phase produces the prediction model,based on which the final code for efficient parsing of XML files is produced through the code generation phase.The RXPF framework has shown a significant improvement in performance varying from 9.54%to 32.34%over other existing models used for parsing XML files.
文摘In this paper, we present a modular incremental statistical model for English full parsing. Unlike other full parsing approaches in which the analysis of the sentence is a uniform process, our model separates the full parsing into shallow parsing and sentence skeleton parsing. In shallow parsing, we finish POS tagging, Base NP identification, prepositional phrase attachment and subordinate clause identification. In skeleton parsing, we use a layered feature-oriented statistical method. Modularity possesses the advantage of solving different problems in parsing with corresponding mechanisms. Feature-oriented rule is able to express the complex lingual phenomena at the key point if needed. Evaluated on Penn Treebank corpus, we obtained 89.2% precision and 89.8% recall.
基金Supported in part by the National Science Foundation of Liaoning Province,China(No.2020-MS-360)Shenyang Science and Technology Bureau(No.RC210267)。
文摘AIM: To compare the postoperative visual acuity among eyes with proliferative diabetic retinopathy(PDR) of different stages after pars plana vitrectomy(PPV) in type 2 diabetic patients. METHODS: A retrospective study was conducted for PDR eyes undergoing PPV in type 2 diabetic patients. All patients were divided into three groups based on Chinese Ocular Fundus Diseases Society(COFDS) classification for PDR: Group A(primary vitreous hemorrhage), Group B(primary fibrovascular proliferation) and Group C(primary vitreous hemorrhage and/or fibrovascular proliferative combined with retinal detachment). The postoperative visual acuity and the change between postoperative and preoperative visual acuity were compared among three groups. The associated risk factors for postoperative visual acuity were analyzed in the univariate and multiple linear aggression. RESULTS: In total, 195 eyes of 195 patients were collected in this study, including 71 eyes of 71 patients in Group A, 75 eyes of 75 patients in Group B and 49 eyes of 49 patients in Group C. The eyes in Group A got better postoperative best-corrected visual acuity(BCVA) compared to the eyes in Group B and C(0.48±0.48 vs 0.89±0.63, P<0.001;0.48±0.48 vs 1.04±0.67, P<0.001;respectively). The eyes in Group A got more improvement of BCVA compared to the eyes in Group B and C(1.07±0.70 vs 0.73±0.68, P=0.004;1.07±0.70 vs 0.77±0.78, P=0.024;respectively). In the multiple linear regression analysis, primary fibro-proliferative type(β=0.194, 95%CI=0.060-0.447, P=0.01), retinal detachment type(β=0.244, 95%CI=0.132-0.579, P=0.02), baseline log MAR BCVA(β=0.192, 95%CI=0.068-0.345, P=0.004), silicone oil tamponade(β=0.272, 95%CI=0.173-0.528, P<0.001) was positively correlated with postoperative log MAR BCVA. Eyes undergoing phacovitrectomy had better postoperative BCVA(β=-0.144, 95%CI=-0.389 to-0.027, P=0.025). CONCLUSION: PDR eyes of primary vitreous hemorrhage type usually have better visual acuity prognosis compared to primary fibrovascular proliferation type and retinal detachment type. COFDS classification for PDR may have a high prognostic value for postoperative visual outcome and surgical management indications.
基金supported by the Fundamental Research Funds for the Central Universities, No. lzujbky-2011-83Project of the International Cooperation and Communion Department of Chinese Education Ministry (46th batch)the Science Foundation of Key Laboratory of Preclinical Study for New Drugs of Gansu Province, No. GSKFKT-0804
文摘Because neurons are susceptible to oxidative damage and thioredoxin reductase 1 is extensively distributed in the central nervous system and has antioxidant properties, we speculated that the enzyme may be involved in the pathogenesis of Parkinson's disease. A Parkinson's disease model was produced by intraperitoneal injection of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine into C57BL/6 mice. Real-time reverse transcription-PCR, western blot analysis and colorimetric assay showed that the levels of thioredoxin reductase 1 mRNA and protein were decreased, along with a significant reduction in thioredoxin reductase activity, in the midbrain of Parkinson's disease mice compared with normal mice. Immunohistochemical staining revealed that the number of thioredoxin reductase 1-positive neurons in the substantia nigra pars compacta of Parkinson's disease mice was significantly decreased compared with normal mice. These experimental findings suggest that the expression of thioredoxin reductase 1 in the substantia nigra pars compacta of Parkinson's disease mice is significantly decreased, and that the enzyme may be associated with disease onset.
文摘AIM:To describe the clinical characters of rhegmatogenous retinal detachment(RRD) associated with massive spontaneous suprachoroidal hemorrhage(SSCH). To evaluate optimal timing and prognosis of pars plana vitrectomy.METHODS:A retrospective review of 6 cases(6 eyes)of RRD and massive SSCH among 3772 cases of RRD was conducted. All of 6 patients were treated with twenty-gauge vitrectomy, suprachoroidal blood drainage,phacoemulsification(PHACO) or lensectomy and silicon oil tamponade. The clinical characters, intraoperative findings and treatment outcomes were reported.RESULTS:In the 6 affected eyes of 6 patients(3 men and 3 women; mean age, 53.83y; range 34-61y),preoperative visual acuity ranged from faint light perception(LP) to counting finger(CF). The average interventional duration from visual decreased to surgery was 12.8 d(range 9-15d). All eyes were associated with high myopia and the mean ocular length was 30.32 mm(range 28.14-32.32 mm). Choroidal hemorrhage were successfully drained in the operation of all 6 eyes.Intraoperative findings showed there were multiple retinal breaks in all 6 eyes and in 4 eyes breaks were along supratemporal and/or infratemporal retinal vascular arcade, especially in the edge of chorioretinal atrophy areas. These patients were followed up from 6 to 34mo(Mean, 23.5mo). The best-corrected visual acuity after surgery varied from CF to 20/100, with improvement in 5eyes(83.33%) and no change in 1 eye(16.67%). Ocular hypertension ocurred in 1 eye(16.67%), which wassuccessfully treated by silicon oil removal combined with trabeculectomy. In 4 eyes, tractional retinal detachment caused by proliferative vitreoretinopathy(PVR) appeared and a secondary surgery of pre-retinal membrane peeling and silicon oil retained were performed. In 4eyes, silicon oil cannot be removed. The initial and final reattachment rates were 33.33% and 66.67%, respectively.CONCLUSION:RRD associated with massive SSCH is an extremely rare event. The most common risk factor is long axial length. Vitrectomy and choroidal blood drainage can effectively remove suprachoroidal hemorrhage and promote retinal reattachment in these eyes. However, silicon oil could not be removed in most eyes and final visual acuities are generally poor.
文摘AIMTo evaluate outcomes of combined pars plana vitrectomy and Baerveldt glaucoma implant (PPV-BGI) placement for refractory glaucoma.METHODSThe medical records of 92 eyes (89 patients) that underwent PPV-BGI were retrospectively reviewed, including 43 eyes with neovascular glaucoma (NVG) and 49 eyes with other types of glaucoma (non-NVG).RESULTSOutcome measures were visual acuity (VA), intraocular pressure (IOP), glaucoma medical therapy, complications, and success [VA>hand motions (HM), IOP≥6 mm Hg and ≤21 mm Hg, no subsequent glaucoma surgery]. Cumulative success rates for the non-NVG group and NVG group were 79% and 40% at 1y, respectively (P=0.038). No difference in the rates of surgical success were found between pars plana and anterior chamber tube placement. Preoperative IOP (mean±SD) was 30.3±11.7 mm Hg in the Non-NVG group and 40.0±10.6 mm Hg in the NVG group, and IOP was reduced to 15±9.5 mm Hg in the non-NVG group and 15±10.5 mm Hg in the NVG at 1y. Number of glaucoma medications (mean±SD) decreased from 2.7±1.3 in the non-NVG group and 2.8±1.3 in the NVG group preoperatively to 0.76±1.18 in the non-NVG group and 0.51±1.00 in the NVG group at 1y. Improvement in VA of ≥2 Snellen lines was observed in 25 (27%) eyes, although only 33% of non-NVG eyes and 2.3% of NVG eyes maintained VA better than 20/200 at 1y. Nonclearing vitreous hemorrhage was the most common postoperative complication occurring in 16 (17%) eyes, and postoperative suprachoroidal hemorrhages developed in 5 (5.4%) eyes.CONCLUSIONPPV-BGI is a viable surgical option for eyes with refractory glaucoma, but visual outcomes are frequently poor because of ocular comorbidities, especially in eyes with NVG. The location of tube placement does not influence surgical outcome and should be left to the discretion of the surgeon.
基金Supported by the Innovation Research Project of the Eye Hospital of Wenzhou Medical University (No. YNCX201308)
文摘AIM: To report the results of rhegmatogenous retinal detachment(RRD) repair after pars plana vitrectomy(PPV) without operative use of heavy liquid, and utilizing air tamponade in selected cases.METHODS: RRD patients without severity of proliferative vitreoretinopathy C2 or more underwent PPV without operative use of heavy liquid, and utilizing air tamponade were consecutively enrolled. Alternative postoperative facedown position or lateral position was required for 3-5 d.RESULTS: Totally 36 eyes of 36 patients(24 males, 66.7%) aged 53.8±10.9 y underwent this modified surgery. The mean number of retinal break was 2.1±1.3. Most of the eyes(29, 80.6%) had retinal detachment involving more than one quadrant. Twenty-two(61.1%) eyes with cataract had combined phacoemulsification and intraocular lens implantation. The mean follow up time was 4.6±1.8 mo. Two eyes with retinal redetachment underwent a second retinal repair surgery with silicone oil tamponade, yielding the primary reattachment rate to 94.4%(34/36). Six(16.7%) eyes had intraocular pressure higher than 25 mm Hg. The visual acuity(logMAR) improved from 0.98±0.74 preoperatively to 0.52±0.31 postoperatively(P〈0.001). CONCLUSION: The success rate of this modified retinal repair surgery is comparable with traditional surgery. This technique can be considered for certain retinal detachment patients, since its apparent advantages included lower surgical complications, reduced surgery expenditure, shorter time for postoperative facedown position, and avoiding silicone oil removal surgery.
基金supported by National Key Basic Research Program of China (No.2014CB340600)partially supported by National Natural Science Foundation of China (Grant Nos.61332019,61672531)partially supported by National Social Science Foundation of China (Grant No.14GJ003-152)
文摘Information content security is a branch of cyberspace security. How to effectively manage and use Weibo comment information has become a research focus in the field of information content security. Three main tasks involved are emotion sentence identification and classification,emotion tendency classification,and emotion expression extraction. Combining with the latent Dirichlet allocation(LDA) model,a Gibbs sampling implementation for inference of our algorithm is presented,and can be used to categorize emotion tendency automatically with the computer. In accordance with the lower ratio of recall for emotion expression extraction in Weibo,use dependency parsing,divided into two categories with subject and object,summarized six kinds of dependency models from evaluating objects and emotion words,and proposed that a merge algorithm for evaluating objects can be accurately evaluated by participating in a public bakeoff and in the shared tasks among the best methods in the sub-task of emotion expression extraction,indicating the value of our method as not only innovative but practical.
文摘AIM:To describe and evaluate the efficacy of Ahmed glaucoma valve implantation(AGV)combined with pars plana vitrectomy(PPV)in a single surgical act for the treatment of advanced neovascular glaucoma(NVG).METHODS:Retrospective observational case series included 51 eyes from 50 patients with severe NVG treated with PPV,AGV,and panretinal photocoagulation and/or cryotherapy in a single surgical act during a 13-year period(2005-2018).Preoperative,intraoperative and postoperative data at day 1 and months 1,3,6,21,and 24 were systematically collected.Definition of surgical success was stablished at IOP between 6 and 21 mm Hg with or without topical treatment.RESULTS:Main indications for surgery were NVG secondary to proliferative diabetic retinopathy(39.2%)and central retinal vein occlusion(37.3%).Mean(±SD)preoperative IOP was 42.0±11.2 mm Hg decreasing to 15.5±7.1 mm Hg at 12 mo and 15.8±9.1 mm Hg at 24 mo of follow up.Cumulative incidence of success of IOP control was 76.0%at first postoperative month,reaching 88.3%at 6 mo.Prevalence of successful IOP control at long term was 74.4%at 12 mo and 71.4%at 24 mo.Eye evisceration for unsuccessful NVG management was required in 1 case(2.0%).CONCLUSION:Combination of AGV implantation and PPV in a single act may be a suitable option for severe forms of NVG in a case-by-case basis for effective IOP control and a complete panretinal photocoagulation.
文摘AIM: To determine the rate and possible contributors for post-pars plana vitrectomy(PPV) epiretinal membrane(ERM) in patients treated for rhegmatogenous retinal detachment(RRD). METHODS: This prospective, nonrandomized study comprised 47 consecutive patients(47 eyes) with acute RRD treated with 23 G post-PPV. All participants were followed prospectively for 6 mo for the development of ERM using spectral domain optical coherence tomography. Preoperative and intraoperative data were collected by questionnaires to surgeons. Main outcome measure was the percentage of the ERM formation following post-PPV for RRD. RESULTS: ERM developed postoperatively in 23 eyes(48.9%), none necessitated surgical removal. There was a statistically significant difference between patients with and without ERM postoperatively in preoperative best corrected visual acuity(median log MAR 1.9 vs 0.3, respectively;P=0.003) rate of macula-off(69.6% vs 37.5%, respectively, P=0.028), and rate of ≥5 cryo-applications(55.6% and 18.8%, respectively, P=0.039). ERM developed mainly between the 1st and 3rd months of follow-up. Macula-off status increased the risk of ERM, with the odds ratio of 3.81(P=0.031). CONCLUSION: ERM is a frequent post RRD finding, and its development is associated with macula-off RRD.
文摘AIM:To compare changes in anterior segment topography and axial length(AL)evaluated with Pentacam and IOL Master after pars plana vitrectomy(PPV)performed with and without vitreous base shaving.METHODS:This prospective study included patients who underwent PPV or phacoemulsification+PPV(Phaco+PPV)for various indications.Patients who underwent total posterior hyaloid detachment and excessive vitreous base shaving with scleral indentation were referred to as complete PPV(c-PPV).The patients whom posterior hyaloid was separated as far as the posterior arcades and vitreous base shaving with scleral depression was not performed were classified as the partial PPV(p-PPV)group.All patients underwent detailed ophthalmologic examinations preoperatively and lwk,I,and 3mo postoperatively.Changes in the anterior chamber depth(ACD),anterior chamber volume(ACV),iridocorneal angle(ICA)f central corneal thickness(Cd),and keratometric measurements(K1 and K2)were evaluated with Pentacam HR.Changes in the AL measurements were analyzed with IOL Master.RESULTS:A significant increase in ACD was observed in c-PPV cases(P=0.02),but this increase was not significant in the p-PPV group(P=0.053).In contrast,ICA increased significantly in the c-PPV group(P=0.02)but decreased in the p-PPV group(P=0.09).BCVA was significantly improved in the c-PPV group from week 1(P<0.001)while the increase in the p-PPV group reached significance at 3mo(P=0.035).Cd increased in the first week and later returned to baseline in both groups.No significant differences in the other parameters were observed between the groups,and there were no significant changes in intraocular pressure,ACV,AL,K1 or K2 values(P>0.05 for all).CONCLUSION:Incomplete posterior hyaloid excision and not removing the vitreous base in PPV surgeries may create a more stable anterior chamber,thus preventing the downward movement of the lens-iris diaphragm,and may cause ciliary body retraction,thereby reducing ICA.Awareness of these effects can provide some amount of guidance to physicians in selecting the appropriate PPV procedure and preempting surgical complications.
基金Project(61262035) supported by the National Natural Science Foundation of ChinaProjects(GJJ12271,GJJ12742) supported by the Science and Technology Foundation of Education Department of Jiangxi Province,ChinaProject(20122BAB201033) supported by the Natural Science Foundation of Jiangxi Province,China
文摘Head-driven statistical models for natural language parsing are the most representative lexicalized syntactic parsing models, but they only utilize semantic dependency between words, and do not incorporate other semantic information such as semantic collocation and semantic category. Some improvements on this distinctive parser are presented. Firstly, "valency" is an essential semantic feature of words. Once the valency of word is determined, the collocation of the word is clear, and the sentence structure can be directly derived. Thus, a syntactic parsing model combining valence structure with semantic dependency is purposed on the base of head-driven statistical syntactic parsing models. Secondly, semantic role labeling(SRL) is very necessary for deep natural language processing. An integrated parsing approach is proposed to integrate semantic parsing into the syntactic parsing process. Experiments are conducted for the refined statistical parser. The results show that 87.12% precision and 85.04% recall are obtained, and F measure is improved by 5.68% compared with the head-driven parsing model introduced by Collins.
基金国家高技术研究发展计划(863计划),the National Natural Science Foundation of China
文摘Natural language parsing is a task of great importance and extreme difficulty. In this paper, we present a full Chinese parsing system based on a two-stage approach. Rather than identifying all phrases by a uniform model, we utilize a divide and conquer strategy. We propose an effective and fast method based on Markov model to identify the base phrases. Then we make the first attempt to extend one of the best English parsing models i.e. the head-driven model to recognize Chinese complex phrases. Our two-stage approach is superior to the uniform approach in two aspects. First, it creates synergy between the Markov model and the head-driven model. Second, it reduces the complexity of full Chinese parsing and makes the parsing system space and time efficient. We evaluate our approach in PARSEVAL measures on the open test set, the parsing system performances at 87.53% precision, 87.95% recall.
基金the National Natural Science Foundation of China (No.60435020, 60575042 and 60503072).
文摘This paper proposes a new way to improve the performance of dependency parser: subdividing verbs according to their grammatical functions and integrating the information of verb subclasses into lexicalized parsing model. Firstly,the scheme of verb subdivision is described. Secondly,a maximum entropy model is presented to distinguish verb subclasses. Finally,a statistical parser is developed to evaluate the verb subdivision. Experimental results indicate that the use of verb subclasses has a good influence on parsing performance.