内镜黏膜下剥离术治疗食管和胃早癌及癌前病变的价值以及术后病理差异分析(附337例报告)

目的探讨内镜黏膜下剥离术(ESD)治疗食管和胃早癌及癌前病变的临床疗效,并分析手术前后标本病理特点的差异。方法 337例研究对象术前经胃镜活检标本检查确诊为早期食管癌、早期胃癌或癌前病变,均经ESD治疗,观察其临床表现特征、术前及术后病理特点的差异等。结果共切除病灶372处,其中多发病变30例。术前钳取活检总正确率为55.91%(208/372),漏诊率6.72%(25/372),对高级别上皮内瘤变(HGIN)和早癌的低估率为19.86%(29/146)。边缘/基底阳性率4.57%(17/372)。结论 ESD是治疗食管及胃早癌及癌前病变的有效方法,并且可以提高病理的诊断正确率。ESD术前的病理活检正确率需进一步提高。ESD病理标本阳性与术前判断病变、ESD操作有关。

Urban and river flooding:Comparison of flood risk management approaches in the UK and China and an assessment of future knowledge needs

Increased urbanisation,economic growth,and long-term climate variability have made both the UK and China more susceptible to urban and river flooding,putting people and property at increased risk.This paper presents a review of the current flooding challenges that are affecting the UK and China and the actions that each country is undertaking to tackle these problems.Particular emphases in this paper are laid on(1)learning from previous flooding events in the UK and China,and(2)which management methodologies are commonly used to reduce flood risk.The paper concludes with a strategic research plan suggested by the authors,together with proposed ways to overcome identified knowledge gaps in flood management.Recommendations briefly comprise the engagement of all stakeholders to ensure a proactive approach to land use planning,early warning systems,and water-sensitive urban design or redesign through more effective policy,multi-level flood models,and data driven models of water quantity and quality.

B7-H4 expression is elevated in human U251 glioma stem-like cells and is inducible in monocytes cultured with U251 stem-like cell conditioned medium

Previous studies indicated that B7-H4,the youngest B7 family,negatively regulates T cell-mediated immunity and is significantly overexpressed in many human tumors.Tumor stem cells are purported to play a role in tumor renewal and resistance to radiation and chemotherapy.However,the link between B7-H4and tumor stem cells is unclear.In this study,we investigated B7-H4 expression in the medium of human glioma U251 cell cultures.Immunofluorescence results showed that U251 cells cultured in serum-free medium(supplemented with 2%B27,20 ng/mL epidermal growth factor,20 ng/mL basic fibroblast growth factor)maintained stem-like cell characteristics,including expression of stem cell marker CD133 and the neural progenitor cell markers nestin and SOX2.In contrast,U251 cells cultured in serum-containing medium highly expressed differentiation marker glial fibrillary acidic protein.Flow cytometry analysis showed serum-free medium-cultured U251 cells expressed higher intracellular B7-H4 than serumcontaining medium-cultured U251 cells(24%-35%vs.8%-11%,P<0.001).Immunofluorescence in purified monocytes from normal human peripheral blood mononuclear cells revealed moderate expression of B7-H4 after stimulation with conditioned medium from U251 cells cultured in serum-containing medium.Moreover,conditioned medium from U251 stem-like cells had a significant stimulation effect on B7-H4expression compared with serum-containing conditioned medium(P<0.01).Negative costimulatory molecule B7-H4 was preferentially expressed in U251 stem-like cells,and conditioned medium from these cells more effectively induced monocytes to express B7-H4 than conditioned medium from U251 cells cultured in the presence of serum.Our results show that U251 stem-like cells may play a more crucial role in tumor immunoloregulation with high expression of B7-H4.

STUDY ON PYROLYSIS OF POLYPHENYLSILSESQUIOXANE

X-ray photoelectron spectroscopy and Raman spectroscopy were' used to determine the chemical change of polyphenylsilsesquioxane (PPSQ) during pyrolysis in flowing nitrogen. Two temperature ranges were found for pyrolysed PPSQ below and above 600degreesC, respectively. The former is related to the rearrangement of PPSQ backbone and the latter reflects that most of backbone structure of PPSQ might be broken down and unorganized. Carbon formed in carbonization of PPSQ sample pyrolysed at 900degreesC should be sp(3) bonded carbon with crystallite size effects or defects.

Large post-liquefaction deformation of sand:Mechanisms and modeling considering water absorption in shearing and seismic wave conditions

Large deformation of sand due to soil liquefaction is a major cause for seismic damage.In this study,the mechanisms and modeling of large post-liquefaction deformation of sand considering the significant influence of water absorption in shearing and seismic wave conditions.Assessment of case histories from past earthquakes and review of existing studies highlight the importance of the two factors.Based on the micro and macro scale mechanisms for post-liquefaction shear deformation,the mechanism for water absorption in shearing after initial liquefaction is revealed.This is aided by novel designed constant water-absorption-rate shear tests.Water absorption in shearing can be classified into three types,including partial water absorption,complete water absorption,and compulsory water absorption.Under the influence of water absorption in shearing,even a strongly dilative sand under naturally drained conditions could experience instability and large shear deformation.The mechanism for amplification of post-liquefaction deformation under surface wave load is also explained via element tests and theoretical analysis.This shows that surface wave–shear wave coupling can induce asymmetrical force and resistance in sand,resulting in asymmetrical accumulation of deformation,which is amplified by liquefaction.A constitutive model,referred to as CycLiq,is formulated to capture the large deformation of sand considering water absorption in shearing and seismic wave conditions,along with its numerical implementation algorithm.The model is comprehensively calibrated based on various types of element tests and validated against centrifuge shaking table tests in the liquefaction experiments and analysis projects(LEAP).The model,along with various numerical analysis methods,is adopted in the successful simulation of water absorption in shearing and Rayleigh wave-shear wave coupling induced large liquefaction deformation.Furthermore,the model is applied to high-performance simulation for large-scale soil-structure interaction in liquefiable ground,including underground structures,dams,quay walls,and offshore wind turbines.

Does Early Postsurgical Temozolomide Plus Concomitant Radiochemotherapy Regimen Have Any Benefit in Newly-diagnosed Glioblastoma Patients？ A Multi-center, Randomized, Parallel, Open-label, Phase II Clinical Trial

Background： The radiochemotherapy regimen concomitantly employing temozolomide （TMZ） chemotherapy and radiotherapy （RT） 4 weeks after surgery, followed by 6 cycles of TMZ is a common treatment for glioblastoma （GBM）. However, its median overall survival （OS） is only 14.6 months. This study was to explore the effectiveness and safety of early TMZ chemotherapy between surgery and chemoradiotherapy plus the standard concomitant radiochemotherapy regimen. Methods： A randomized, parallel group, open-label study of 99 newly diagnosed GBM patients was conducted at 10 independent Chinese neurosurgical departments from June 2008 to June 2012. Patients were treated with concomitant radiochemotherapy regimen plus early postsurgical temozolomide （early TMZ group） or standard concomitant radiochemotherapy regimen （control group）. Overall response was assessed based on objective tumor assessments, administration ofcorticosteroid and neurological status test. Hematological, biochemical, laboratory, adverse event （AE）, and neurological condition were measured for 24 months of tbllow-up. The primary efficacy endpoint of this study was overall survival （OS）. The secondary endpoint was progression free survival （PFS）. Results： The median OS time in the early TMZ group was 17.6 months, compared with 13.2 months in the control group （log-rank test P 0.021 ）. In addition, the OS rate in the early TMZ group was higher at 6, 12, and 18 months than in the control group, respectively （P 〈 0.05）. The median PFS time was 8.7 months in the early TMZ group and 10.4 months in the control group （log-rank test P = 0.695）. AEs occurred in 29 （55.8%） and 31（73.8%） patients respectively in early and control groups, including nausea （15.4% vs. 33.3%）, vomiting （7.7% vs. 28.6%）, fever （7.7% vs. 11.9%）, and headache （3.8% vs. 23.8%）. Only 30.8% and 33.3% were drug-related, respectively. Conclusions： Addition of TMZ chemotherapy in the early break of the standard concomitant radiochemotherapy regimen was well tolerated and significantly improved the OS of the GBM patients, compared with standard concomitant radiochemotherapy regimen. However, a larger randomized trial is warranted to verify these results.

Case Report:Granulomatous hypophysitis:two case reports and literature review

Granulomatous hypophysitis （GRH） is extremely rare and commonly presents with chronic inflammatory of the enlarged pituitary gland. In our study, 66-year-old and 57-year-old women, both Chinese, were diagnosed with GRH presenting preoperatively definite imageology characters as pituitary adenoma. The 66-year-old woman presented with a year of headache, half a year of gradual decrease of visual acuity, and one month of right ptosis. Serum prolaetin level was slightly elevated. Screening computed tomography （CT） scanning revealed typical low density mass found on the enlarged sella, which demonstrated invasive extension from the sella to the right cavernous sinus by contrast enhanced magnetic resonance imaging （MRI）. Consequently, the patient was diagnosed with probable invasive pituitary adenoma. The other 57-year-old woman complained a light headache and had been previously treated as nonfunctional pituitary adenoma in other hospital. Finally these two patients underwent transsphenoidal microsurgery and were diagnosed with GRH according to postoperative histopathology. They then were treated with steroid. During the follow-up, the clinical symptoms such as headache, visual damage, and ptosis vanished, and the mass of the sellae dramatically shrank on repeated MR images. Clinically and radiologically, GRH is a rare sellar entity easily to be misdiagnosed as a pituitary adenoma. Trans-sphenoidal surgery can decompress the optical nerve or oculomotornerve as a therapeutic strategy, and support biopsy or further pathological diagnosis. However, the hormonal therapy should be emphasized both as diagnostic and therapeutic strategies. Conservative and tentative steroid treatment should be performed in preoperative period without acute nerve damage.

Predictive significance of serum inhibin B on testicular haploid gamete retrieval outcomes in nonobstructive azoospermic men

The purpose of this study was to determine the diagnostic accuracy of serum inhibin B(INHB)as a predictor of the retrieval outcome of testicular haploid gametes(spermatids and testicular spermatozoa)in nonobstructive azoospermic men.Serum hormone levels,testicular volume,and histological evaluation were performed in 403 Chin ese non obstructive azoospermic men.Testicular haploid gamete was successfully retrieved in 213 of 403 patients(52.85%).The haploid gamete group always had higher INHB levels than the non-haploid gamete group.According to the receiver operating characteristic(ROC)curve analysis,INHB was a good predictor of testicular haploid gamete retrieval outcome in all patients(sensitivity:77.93%and specificity:91.58%)and patients with normal follicle-stimulating hormone(FSH;sensitivity:88.52%and specificity:70.83%).The area under the ROC curve(AUC)of INHB was similar to that of FSH in all patients or patients with normal FSH.In patients with elevated FSH,INHB was superior to FSH in predicting the presence of haploid gamete(AUC:0.73 vs 0.55,P<0.05),with a sensitivity of 60.00%and a specificity of 80.28%.It con eluded that serum INHB as an effective marker for spermatoge nesis was a sign ificant predictor of testicular haploid gamete retrieval outcomes in nonobstructive azoospermic men.Especially,INHB is superior to FSH in predicting the presenee of haploid gamete in the patients with elevated FSH.

A constrained neural network model for soil liquefaction assessment with global applicability

A constrained back propagation neural network(C-BPNN)model for standard penetration test based soil liquefaction assessment with global applicability is developed,incorporating existing knowledge for liquefaction triggering mechanism and empirical relationships.For its development and validation,a comprehensive liquefaction data set is compiled,covering more than 600 liquefaction sites from 36 earthquakes in 10 countries over 50 years with 13 complete information entries.The C-BPNN model design procedure for liquefaction assessment is established by considering appropriate constraints,input data selection,and computation and calibration procedures.Existing empirical relationships for overburden correction and fines content adjustment are shown to be able to improve the prediction success rate of the neural network model,and are thus adopted as constraints for the C-BPNN model.The effectiveness of the C-BPNN method is validated using the liquefaction data set and compared with that of several liquefaction assessment methods currently adopted in engineering practice.The C-BPNN liquefaction model is shown to have improved prediction accuracy and high global adaptability.

Application of Keyhole Microneurosurgery in China

INTRODUCTIONMicroneurosurgery made its debut in the early 1960s. It became popular in the medical field and became a primary operation method in neurosurgery since it improved the efficacy of neurosurgery with a less surgery-related injury. Over the past five decades, the accumulation of experience of microsurgery, improvement of microsurgery techniques, refined micro-instruments, and advanced preoperative diagnostic imaging allowed the evolution of microneurosurgery techniques and further reduced surgery-related trauma.

Effects of antiepileptic drugs on bone mineral density and bone metabolism in children: a meta-analysis

Objective： The aim of our meta-analysis was to assess the effects of antiepileptic drugs on bone mineral density and bone metabolism in epileptic children. Methods： Searches of Pub Med and Web of Science were undertaken to identify studies evaluating the association between antiepileptic drugs and bone mineral density and bone metabolism. Results： A total of 22 studies with 1492 subjects were included in our research. We identified：（1） a reduction in bone mineral density at lumbar spine（standardized mean difference（SMD）=-0.30, 95% confidence interval（CI） [-0.61,-0.05]）, trochanter（mean difference（MD）=-0.07, 95% CI [-0.10,-0.05]）, femoral neck（MD=-0.05, 95% CI [-0.09,-0.02]）, and total body bone mineral density（MD=-0.33, 95% CI [-0.51,-0.15]）;（2） a reduction in 25-hydroxyvitamin D（MD=-3.37, 95% CI [-5.94,-0.80]） and an increase in serum alkaline phosphatase（SMD=0.71, 95% CI [0.38, 1.05]）;（3） no significant changes in serum parathyroid hormone, calcium, or phosphorus. Conclusions： Our meta-analysis suggests that treatment with antiepileptic drugs may be associated with decreased bone mineral density in epileptic children.

A bidirectional brain-computer interface for effective epilepsy control

Brain-computer interfaces(BCIs) can provide direct bidirectional communication between the brain and a machine. Recently, the BCI technique has been used in seizure control. Usually, a closed-loop system based on BCI is set up which delivers a therapic electrical stimulus only in response to seizure onsets. In this way, the side effects of neurostimulation can be greatly reduced. In this paper, a new BCI-based responsive stimulation system is proposed. With an efficient morphology-based seizure detector, seizure events can be identified in the early stages which trigger electrical stimulations to be sent to the cortex of the brain. The proposed system was tested on rats with penicillin-induced epileptic seizures. Online experiments show that 83% of the seizures could be detected successfully with a short average time delay of 3.11 s. With the therapy of the BCI-based seizure control system, most seizures were suppressed within 10 s. Compared with the control group, the average seizure duration was reduced by 30.7%. Therefore, the proposed system can control epileptic seizures effectively and has potential in clinical applications.

Hydrogen induced room-temperature ferromagnetism in Co-doped ZnO: first-principles and Monte Carlo study

The structural stability, vibrational and magnetic properties of hydrogen doped ZnO:Co have been studied by first-principles calculations based on density functional theory. Bond-center(BC) sites were identified to be most stable sites for hydrogen, the corresponding vibrational frequencies including anharmonic contributions were calculated. Its magnetic properties were investigated as well. The calculated results reveal that hydrogen could induce the change of electronic transfer, leading to a decrease of magnetic moment. However, the magnetic coupling between Co atoms is greatly strengthen. The results simulated by Monte Carlo method indicate that hydrogen can induce the Curie temperature to increase from 200 to 300 K.

Effects of the mixing degree upstream of the diverging area on the pollutant allocation characteristics of a braided river

The mixing degree upstream of the diverging area is one of the important factors influencing the pollutant allocation characteristics of braided rivers,but the effect remains unclear at present.In this paper,physical model tests were designed to study the effect on the pollutant flux ratio with six branching forms and a series of longitudinal discharge distances.The results indicated that the mixing degree upstream of the diverging area,which is closely related to the longitudinal discharge distance,notably affected the pollutant flux ratio.The lower the mixing degree,the larger was the deviation of the pollutant flux ratio from the discharge ratio.Moreover,a linear relationship was attained between the dimensionless mixing degree and the dimensionless deviation of the pollutant flux ratio from the discharge ratio.Consideration of different branching angles or different water layers or different branches did not affect this trend.The experimental results further demonstrated that the intercept and slope of the aforementioned linear relationship depended on the branching angle and exhibited an opposite monotonicity with a symmetric branch angle as the dividing point.These results help towards a better understanding of the mechanism of the factors influencing pollutant transport in complicated braided rivers,and provide a new approach to predicting the pollutant flux ratio of braided rivers.

有限空间内圆形射流时均流速特性研究（英文）

目的:圆形射流在实际工程中有着重要应用。本文旨在探讨弗劳德数(Fr)、跌坎高度和淹没度的变化对有界圆形射流时均流速在主流方向、横向和垂向上的衰减扩散规律的影响,对圆形射流的现有研究成果作进一步的补充。创新点:1.推导出圆形跌坎射流主流方向上流速与射流距离之间的关系;2.综合考虑了不同Fr、跌坎高度和淹没度对有限空间内的圆形射流流速分布的影响。方法:1.通过理论推导,验证流速测量方法的可行性和合理性;2.通过试验的方法,分析Fr、跌坎高度和淹没度的变化对圆形射流时均流速衰减和扩散的影响规律。结论:1.得出圆形射流主流方向流速衰减的公式;圆形射流的横向流速分布与高斯、柯西-洛伦兹分布吻合较好。2.当Re>1×104时,Fr变化对流速衰减影响较小。3.当X/d<10时,横向和垂向流速扩散与主流方向的距离呈二次方关系。4.时均流速最大值的位置与Fr和S/d无关。

A REAL-TIME AFM STUDY ON CRYSTAL NUCLEATION AND GROWTH IN NANODROPLETS OF ISOTACTIC POLYPROPYLENE

Isotactic polypropylene （iPP） nanodroplets were prepared by using the classical droplet method in this study. The formation of nanodroplets allowed the controlled observation of polymer nucleation as well as access to crystal growth at exceptionally high supercooling in /PP. Three cases including the heterogeneous nucleation and fast crystallization in iPP droplets, the formation of multiple independent homogeneous nuclei within a single droplet and a single nucleus within a single droplet were detected by using atomic force microscopy （AFM） during gradually cooling after remelting the nanodroplets. Moreover, it is found that when the volume of droplet is larger than the value of ca. 130000 nm3, the first case was observed. Otherwise, the latter two cases appeared. The temperature at which the onset of nucleation was observed in individual droplets was found to be mainly dependent on height of the droplets when the size scale of the droplet is comparable to the size of the critical nucleus in at least one dimension, which indicates the nucleation behavior under confinement.

Experimental study of anti-cavitation mechanism of valve lintel natural aeration of high head lock

To study the serious valve top gap cavitation of Datengxia high head single-lift ship lock,the 1:1 scale slice experiment is carried out,to truly reveal the gap flow characteristics,as well as the valve top gap cavitation characteristics and the anti-cavitation mechanism of natural aeration.Three kinds of cavitation,namely,the throat cavitation,the mainstream inner cavitation,and the valve plate cavitation,are determined and they are found to occur step-by-step in the gap section in the development of the cavitation.According to the anti-cavitation mechanism of the natural aeration,the pressure of the gap flow through the ventilation is increased,to avoid the mainstream inner cavitation and the valve plate cavitation,and to weaken the throat cavitation.The negative pressure zone in the gap section gradually extends with the development of the cavitation until the gap section is filled with a stable−10 m water head.When the natural aeration measure is employed,the pressure in the gap section approximately reaches the−2 m water head,and the cavitation disappears.The systematic tests reveal the quadratic polynomial relationship between the pressure in the gap and the ventilation per meter width.The pressure,which corresponds to the maximum value of the ventilation at the beginning of the gap,approximately reaches the−2 m water head,and the pressure and the ventilation reach the equilibrium state limit.When the pressure in the gap increases when the valve is opened,the ventilation gradually decreases until the natural aeration stops.The gap section length for the high head valves has a great effect on the natural aeration and should be long enough to maintain the stable negative pressure in the gap,whereas the throat width has a minimal effect.Results can be used for the anti-cavitation design of the high head lock valve.