mlsa-iai-msu-lab/ru_sci_bench_zho_cite_reranking huggingface dataset:
Enhance of TiO_2 dopants incorporated reduced graphene oxide via RF magnetron sputtering for efficient dye-sensitised solar cells

In particular, the dye-sensitised solar cells (DSSCs) have a high potential in the rational energy conversion efficiency to secure our sustainable energy source. In the present study, advanced radio frequency (RF) magnetron sputtering technique was applied to incorporate titanium dioxide (TiO_2) dopants into reduced graphene oxide (rGO) nanosheet for improving the power conversion efficiency (PCE) of DSSCs device. An optimum TiO_2 content incorporated onto rGO nanosheet plays an important role in improving the PCE of DSSCs by minimising the recombination losses of photo-induced charge carriers. Based on the results obtained, 40-s sputtering duration for incorporating TiO_2 dopants onto rGO nanosheet exhibits a maximum PCE of 8.78% than that of pure rGO film (0.68%). In fact, the presence of optimum content of TiO_2 dopants within rGO nanosheet could act as mediators for efficient separation photo-induced charge carriers. However, the excessive of sputtering duration (e.g. 60 s) of TiO_2 dopants onto rGO nanosheet results higher charge recombination and lowers the PCE of DSSCs (5.39%).
A simple calculation model for thermodynamic equilibrium information between precipitation and matrix

A simple theoretical model was developed to predict equilibrium between precipitate and matrix in a multicomponent microalloyed steel.The solute concentration in the matrix,the composition and the volume fraction of the precipitated second phases,and the reduction in critical precipitation temperature of AlN induced by carbonitride were quantified by the proposed thermodynamic model.The results predicted by the developed model and those by other approaches are in a good agreement.The main advantages of this model over the existing models are that the process of formulation derivation is simple and the model can be easily solved by a personal program.
性染色体数目异常疾病诊断技术研究进展

性染色体数目异常疾病是一类严重困扰人类生活的综合征,患者多能生存,但常有性腺发育不全、多发畸形、不育等异常表现。该病无法治愈,经激素替代治疗等干预措施可有效缓解症状,但早期确诊严重依赖于相关临床诊断技术的发展。该文拟就现今常见检测性染色体数目异常技术的发展作一综述,比较各技术优缺点及评价其在临床诊断中的应用价值,以方便检验工作者科学合理地采用相关技术,为临床提供更为准确可靠的实验室依据,推进对该类疾病的诊治与研究。
Recent Advances in Hydrometallation of Alkenes and Alkynes via the First Row Transition Metal Catalysis

Hydrometallation of alkenes and alkynes provides a straightforward route to access alkyl- or alkenyl-metal reagents, which have a wide range of applications in organic transformations. In recent years, the first row transition metals (such as copper, nickel, cobalt, iron, etc.) have emerged high activity and selectivity in this area with the aid of a variety of ligands. This review covers the recent advances in the hydrometallation of minimally functionalized unsaturated C—C bonds (including alkenes, alkynes, dienes, allenes, enynes, etc.), as well as transformations involving catalytic hydrometallation process via the first row transition metal catalysis.
Synthesis of Aryl Hydrazines via CuI/BMPO Catalyzed Cross-Coupling of Aryl Halides with Hydrazine Hydrate in Water

The N,N’-bis(2,6-dimethylphenyl)oxalamide was discovered as a powerful ligand for Cu-catalyzed cross-coupling of aryl halides with hydrazine hydrate, leading to the formation of a variety of aryl hydrazines at 80 o C in water under the assistance of K_3PO_4 and 4 mol% cetyltrimethylammonium bromide from aryl bromides and aryl iodides. Good to excellent yields were observed in most cases.
Empirical formulae for electric double-layer repulsion between two arbitrarily inclined clay particles

To understand the mesoscopic mechanism of clayey soil in view of macroscopic behavior, it is essential to quantitatively calculate the electric double-layer repulsion between arbitrarily inclined clay particles. However, suitable calculation methods with high efficiency and accuracy are still rare at present in literature. Based on a great number of numerical calculations of the repulsion between two inclined platy clay particles, explicit empirical formulae for estimating electric double-layer repulsion between clay particles are put forward. Comparison between the empirical solutions and corresponding numerical results shows that the proposed formulae have a reasonable accuracy, and application of the presented formula is easy and efficient.
Amodified logarithmic spiralmethod for determining passive earth pressure

In this study, a modified logarithmic spiral method is proposed to determine the passive earth pressure and failure surface of cohesionless sloping backfill, with presence of wallesoil interface friction. The proposed method is based on a limit equilibrium analysis wherein the assumed profile of the backfill failure surface is a composite of logarithmic spiral and its tangent. If the wallesoil interface is smooth, a straight line does not need to be assumed for the failure surface. The geometry of the failure surface is determined using the Mohr circle analysis of the soil. The resultant passive earth thrust is computed considering equilibrium of moments. The passive earth pressure coefficients are calculated with varied values of soil internal friction angle and cohesion, wall friction angle and inclination angle, and sloping backfill angle. This method is verified with the finite element method (FEM) by comparing the horizontal passive earth pressure and failure surface. The results agree well with other solutions, particularly with those obtained by the FEM. The implementation of the present method is efficient. The logarithmic spiral theory is rigorous and self-explanatory for the geotechnical engineer.
Finite element analyses of slope stability problems using non-associated plasticity

In recent years, finite element analyses have increasingly been utilized for slope stability problems. In comparison to limit equilibrium methods, numerical analyses do not require any definition of the failure mechanism a priori and enable the determination of the safety level more accurately. The paper compares the performances of strength reduction finite element analysis (SRFEA) with finite element limit analysis (FELA), whereby the focus is related to non-associated plasticity. Displacement-based finite element analyses using a strength reduction technique suffer from numerical instabilities when using non-associated plasticity, especially when dealing with high friction angles but moderate dilatancy angles. The FELA on the other hand provides rigorous upper and lower bounds of the factor of safety (FoS) but is restricted to associated flow rules. Suggestions to overcome this problem, proposed by Davis (1968), lead to conservative FoSs; therefore, an enhanced procedure has been investigated. When using the modified approach, both the SRFEA and the FELA provide very similar results. Further studies highlight the advantages of using an adaptive mesh refinement to determine FoSs. Additionally, it is shown that the initial stress field does not affect the FoS when using a Mohr-Coulomb failure criterion.
肝脏离断联合门静脉结扎及肝动脉栓塞治疗晚期肝癌

近年来虽然肝癌的基础和临床研究不断进展,但肝癌发病率和病死率并无明显下降。因此,提高晚期肝癌患者生存率、延长生存时间,改善患者生存质量显得尤为重要。联合门静脉结扎及肝脏离断的二步肝切除术(associating liver partition with portal vein ligation for staged hepatectomy, ALPPS)可以在仅保留肝I段或IV段的前提下完全切除病肝。在该手术的启发下,我院对5例不可切除肝癌患者采用肝脏离断联合门静脉结扎及肝动脉栓塞治的方法治疗,取得较好近期效果。
Graphene-Gold Nanoparticle-modified Electrochemical Sensor for Detection of Kanamycin Based on Target-induced Aptamer Displacement

A highly sensitive and selective label-free electrochemical sensor was developed for the determination of kanamycin. To improve the sensitivity of the electrochemical sensor, graphene-gold nanoparticles were prepared by a one-step electrochemical coreduction process and were modified on the surface of a glassy carbon electrode. The double-stranded DNA(ds-DNA) duplex probe was immobilized onto the graphene-gold nanoparticle-modified electrode. The introduction of target kanamycin induced the displacement of aptamer from the ds-DNA duplex into the solution. Methylene blue(MB) as a redox indicator monitored the current change using differential pulse voltammetry. Under optimal conditions, the designed electrochemical aptasensor exhibited a wide linear range from 0.1 pmol/L to 10 pmol/L with a detection limit of 0.03 pmol/L for kanamycin. The experimental strategy enabled the direct analysis of milk samples, and the results showed high sensitivity and good selectivity.
Mechanical properties and deformation mechanisms of Ti-3Al-5Mo-4.5 V alloy with varied β phase stability

Evolution of deformation mechanisms and mechanical properties of Ti-3Al-5Mo-4.5 V alloy with different β phase stability have been systematically investigated. β phase stability alteration is achieved through quenching temperature variation from dual α+β field(700 ℃) to single β field(880 ℃). Tensile tests at ambient temperature show that apparent yield strength of the alloy experiences an abrupt decrease followed by a significant increase from 700 ℃ to 880 ℃. Work hardening behavior is characterized by transition from the initial two-regime feature to the three-stage outlook. Concurrently, the maximum working hardening rate drops from 14000 MPa to 3000 MPa, which is concurrent with the shrinking volume fraction of primary α phase. Detailed discussion about the relationship between deformation mechanisms and β phase stability has been outlined.
Goldenhar综合征合并喉软骨发育不全患儿眼科手术麻醉一例

Goldernhar综合征患儿的气道管理是整个麻醉管理的重中之重,选择合适的气道管理方案,可以在满足通气和手术需要的同时,减少麻醉相关并发症。此外,还应兼顾并存的疾病制定个体化的麻醉方案。
涎腺上皮肌上皮癌1例

讨论EMC是一种罕见的涎腺上皮性恶性肿瘤,发病率仅占涎腺肿瘤的0.5%,主要发生于头颈部,以腮腺常见.多数EMC CT表现为卵圆形、边界清楚的软组织密度肿块,其内可见不均匀低密度囊变坏死区,增强扫描肿块实性部分持续明显强化,囊性部分不强化.EMC呈浸润性生长,可侵及邻近组织,伴淋巴结及远处转移;组织病理检查可见肌上皮和腺上皮成分,免疫组化SMA、S-100、P53、P63等呈不同程度阳性表达,Ki-67阳性细胞>10%对本病具有诊断价值.EMC常需与腮腺肌上皮瘤、黏液表皮样癌、腺样囊性癌、腺癌、恶性混合瘤等相鉴别:①肌上皮瘤多为边界清楚、密度均匀的软组织肿块,CT增强扫描轻微强化;②黏液表皮样癌特征性表现为内部低密度囊腔;③腺样囊性癌多呈低密度筛样表现,沿神经浸润性生长并可侵及颅内;④腺癌生长快,密度不均,病灶中心常见坏死,边界不清,且常突破涎腺包膜;⑤恶性混合瘤形态不规则,增强扫描呈轻度强化,病灶内可见条状高密度.目前术前影像学诊断EMC困难,最终确诊仍有赖于病理检查.
Practice and Exploration of the Delimitation and Implementation of Urban Development Boundary in Hangzhou

The urban development boundary is an institutional arrangement of overall planning and regulations of regional urban-rural space and ecological space, an important public policy which ensures the healthy and orderly development of urbanization, and one of the key contents that deepens the reform of the economic system. The delimitation of the urban development boundary is considered as a significant content for urban master plan revision and a fundamental basis for urban space layout and infrastructure layout in Hangzhou. As to the methods of delimitation, from the requirements of overall and long-term regional development, with the idea of “seeking the greatest common divisor,” and in line with the layout requirements of population, facilities, and economic activities, the 18 space control elements sorted out according to the laws are integrated to form “one space map” that meets various requirements through interdepartmental negotiation and consultation. It should adhere to the principles including that it should follow related laws, should be implemented in space, should have multi-plan integration, and should be easy in operation. The Hangzhou Municipal Government formulates the Implementation Plan of the Hangzhou Urban Development Boundary, which, in line with the overall requirements of an intensive and highly efficient production space, a livable and moderate living space, and a pleasant and picturesque ecological space, classifies and disposes the present construction outside the urban development boundary, specifies the protection and utilization requirements for the space outside the urban development boundary, promotes the integration of functions inside and outside the urban development boundary, and establishes long-term management mechanisms including formulating regulations, dynamic monitoring, assessments of government performance, and social supervision.
“Street Portraits” of Old City Streets in the New Data Environment: A Case Study on the Old City of Beijing

As China's economic development turns into the “New Normal,” the focus of urban development and construction have transformed from “physical expansion” to “built-up area improvement.” Street, as the most fundamental component of public space, is of great significance to be interpreted and studied. This study attempts to quantify all the composing elements in urban streets to create “Street Portraits” which can clearly describe the characteristics of the street. Taking Beijing as an example, this study aims to make a comprehensive and objective evaluation of the streets in the Old City of Beijing. Methodologically, the properties of a street are identified and categorized into three aspects: street function, street vitality, and street quality, which further helps establish an evaluation indicator system for the “Street Portraits.” In result, various “Street Portraits” of the Old City of Beijing are presented by data visualization, by using the Nightingale Rose diagram tool to integrate all the indicators of individual streets and thus describing the distinctive “Street Portraits.” In the end, the paper discusses how the finding can influence the street space improvement and design in the future.
长三角地区医疗器械产业创新系统要素配置效率动态研究

本文以产业创新系统理论框架为基础,将产业创新系统功能及其演化的规律与医疗器械产业相结合,构建医疗器械产业创新系统分析框架。在该框架下,建立长三角地区医疗器械产业创新系统的指标体系,对创新系统效率进行评价与分析。结果显示,在医疗器械产业创新系统发展的不同阶段,系统对创新要素在数量与质量等方面的需求存在差异,医疗器械产业在动态演化过程中,资金方面的需求正在降低,而人力资源需求日益增加。建议产业发展应关注资源利用效率的下降,重点提高资金利用效率,政府转变角色,增加人才培养。
大黄牡丹汤调节TLR/MyD88/NF-κB-p65信号治疗对急危重症患者急性肠功能障碍的临床研究

目的研究大黄牡丹汤能否通过调节TLR/MyD88/NF-κB-p65信号通路来治疗急危重症患者急性肠功能障碍的临床疗效。方法将57例患者随机分为对照组(30例)与大黄牡丹汤组(27例),另选取16例健康成年人作为正常组。治疗7 d后,3组患者采血,检测血清中SOD、MDA、IL-1β、IL-6、IL-10、TNF-α、TLR2、TLR4、MyD88、NF- κB-p65、p-NF-κB-p65水平,以及血液白细胞中TLR2、TLR4、MyD88、NF-κB-p65、p-NF-κB-p65蛋白表达水平。结果与对照组比较,大黄牡丹汤组血清中MDA、IL-1β、IL-6、TNF-α、TLR2、TLR4、MyD88、NF-κB-p65、p-NF- κB-p65水平显著降低(P < 0.05),IL-10水平、SOD活力显著升高(P < 0.05);血液白细胞中TLR2、TLR4、MyD88、 p-NF-κB-p65蛋白表达水平显著降低(P < 0.05)。结论大黄牡丹汤可通过调控TLR/MyD88/NF-κB-p65信号,对急危重症患者急性肠功能障碍发挥治疗作用。
川芎-天麻不同配比在血瘀型偏头痛大鼠中的药动学行为

目的考察川芎-天麻不同配比在血瘀型偏头痛大鼠中的药动学行为。方法18只大鼠随机分为川芎组、川芎-天麻(1∶ 0.25)组、川芎-天麻(1∶ 1)组,每组6只,分别灌胃给予不同配比剂量的阿魏酸/川芎嗪、天麻素/天麻苷元。采用皮下注射硝酸甘油+肾上腺皮质激素+冰浴法制备血瘀型偏头痛大鼠模型,于颈静脉插入微透析探针实时收集不同时间点血透析液,UPLC-MS法测定样品中阿魏酸、川芎嗪含有量,绘制药时曲线,计算药动学参数。结果对川芎嗪而言,川芎-天麻组其T_(1/2)、C_(max)、AUC_(0~ ∞)与川芎组比较显著增加(P < 0.05,P < 0.01),以1∶ 0.25组更显著(P < 0.05,P < 0.01),并且该组MRT_(0~ ∞)也显著增加(P < 0.01);对阿魏酸而言,川芎-天麻组其C_(max)与川芎组比较显著增加(P < 0.05,P < 0.01),其中1∶ 0.25组T_(1/2)、MRT_(0~ ∞)也显著增加(P < 0.05,P < 0.01),并且该组T_(1/2)、MRT_(0~ ∞)、AUC_(0~ ∞)显著高于1∶ 1组(P < 0.05)。结论天麻可延长川芎中阿魏酸、川芎嗪在体内的作用时间,从而使其更好地发挥治疗血瘀型偏头痛的作用。
Structures of the human pre-catalytic spliceosome and its precursor spliceosome

The pre-catalytic spliceosome (B complex) is preceded by its precursor spliceosome (pre-B complex) and followed by the activated spliceosome (Bact complex). The pre-B-to-B and B-to-Bact transitions are driven by the ATPase/helicases Prp28 and Brr2, respectively. In this study, we report the cryo-electron microscopy structures of the human pre-B complex and the human B complex at an average resolution of 5.7 and 3.8 A, respectively. In the pre-B complex, U1 and U2 small nuclear ribonucleoproteins (snRNPs) associate with two edges of the tetrahedron-shaped U4/U6.U5 tri-snRNP. The pre-mRNA is yet to be recognized by U5 or U6 small nuclear RNA (snRNA), and loop I of U5 snRNA remains unengaged. In the B complex, U1 snRNP and Prp28 are dissociated, the 5'-exon is anchored to loop I of U5 snRNA, and the 5'-splice site is recognized by U6 snRNA through duplex formation. In sharp contrast to S. cerevisiae, most components of U2 snRNP and tri-snRNP, exemplified by Brr2, undergo pronounced rearrangements in the human pre-B-to-B transition. Structural analysis reveals mechanistic insights into the assembly and activation of the human spliceosome.
Investigation of straightforward impedance eduction method on single-degree-of-freedom acoustic liners

In order to address the current aircraft noise problem,the knowledge of impedance of acoustic liners subjected to high-intensity sound and grazing flow is of crucial importance to the design of high-efficiency acoustic nacelles.To this end,the present study is twofold.Firstly,the StraightForward impedance eduction Method (SFM) is evaluated by the strategy that the impedance of a liner specimen is firstly experimentally educed on a flow duct using the SFM,and then its accuracy is checked by comparing the numerical prediction with the measured wall sound pressure of the flow duct.Secondly,the effects of grazing flow and high-intensity sound on the impedance behavior of two single-layer liners are investigated based on comparisons between educed impedance and predictions by three impedance models.The performance of the SFM is validated by showing that the educed impedance leads to excellent agreement between the simulation and the measured wall sound pressure for different grazing flow Mach numbers and Sound Pressure Levels (SPLs) and over a frequency range from 3000 Hz down to 500 Hz.The grazing flow effect generally has the tendency that the acoustic resistance exhibits a slight decrease before it increases linearly with an increase in Mach,predicted successfully by the sound-vortex interaction theoretical model and the Kooi semi-empirical impedance model.However,the Goodrich semi-empirical impedance model gives only a simple linear relation of acoustic resistance starting from Mach zero.Additionally,when the SPL increases from 110 to 140 dB in the present investigation,the acoustic resistance exhibits a significant increase at all frequencies in the absence of flow;however,the resistance decreases slightly under a grazing flow of Mach 0.117.It indicates that the SPL effect can be greatly inhibited when flow is present,and the grazing flow effect can be reduced partly as well at a relatively high SPL.
Aircraft robust multidisciplinary design optimization methodology based on fuzzy preference function

This paper presents a Fuzzy Preference Function-based Robust Multidisciplinary Design Optimization (FPF-RMDO) methodology.This method is an effective approach to multidisciplinary systems,which can be used to designer experiences during the design optimization process by fuzzy preference functions.In this study,two optimizations are done for Predator MQ-1 Unmanned Aerial Vehicle (UAV):(A) deterministic optimization and (B) robust optimization.In both problems,minimization of takeoff weight and drag is considered as objective functions,which have been optimized using Non-dominated Sorting Genetic Algorithm (NSGA).In the robust design optimization,cruise altitude and velocity are considered as uncertainties that are modeled by the Monte Carlo Simulation (MCS) method.Aerodynamics,stability and control,mass properties,performance,and center of gravity are used for multidisciplinary analysis.Robust design optimization results show 46% and 42% robustness improvement for takeoff weight and cruise drag relative to optimal design respectively.
Prenatal Exposure to Perfluorooctane Sulfonate impairs Placental Angiogenesis and Induces Aberrant Expression of LncRNA Xist

Perfluorooctane sulfonate (PFOS) is a class of stable organic compounds with wide industrial,commercial,and consumer applications,such as in textiles,paper,pesticides,and shampoos.It is readily absorbed,but poorly eliminated,with the elimination half-life of approximately 5 years.Hence,there have been concerns regarding its potential damage to human health.Some studies have indicated that the exposure to PFOS might have adverse effects on human gestation.In particular,PFOS can be freely transferred to the placenta,inducing developmental toxicity and causing fetal growth retardation.
Association of HLA-DR3 and HLA-DR15 Polymorphisms with Risk of Systemic Lupus Erythematosus

Background: Systemic lupus erythematosus (SLE) is an autoimmune disease under genetic control. Growing evidences support the genetic predisposition of HLA-DRB1 gene polymorphisms to SLE, yet the results are not often reproducible. The purpose of this study was to assess the association of two polymorphisms of HLA-DRB1 gene (HLA-DR3 and HLA-DR15) with the risk of SLE via a comprehensive meta-analysis. Methods: This study complied with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. Case-control studies on HLA-DRB1 and SLE were searched from PubMed, Elsevier Science, Springer Link, Medline, and Cochrane Library database as of June 2018. Analysis was based on the random-effects model using STATA software version 14.0. Results: A total of 23 studies were retained for analysis, including 5261 cases and 9838 controls. Overall analysis revealed that HLA-DR3 and HLA-DR15 polymorphisms were associated with the significant risk of SLE (odds ratio [OR]: 1.60, 95% confidence interval (CI): 1.316-1.934,P = 0.129 and OR: 1.68,95% CI: 1.334-2.112, P = 0.001,respectively). Subgroup analyses demonstrated that for both HLA-DR3 and HLA-DR15 polymorphisms, ethnicity was a possible source of heterogeneity. Specifically, HLA-DR3 polymorphism was not associated with SLE in White populations (OR: 1.60,95% CI: 1.320-1.960, P = 0.522) and HLA-DR15 polymorphism in East Asian populations (OR: 1.65, 95% CI: 1.248-2.173, P = 0.001). In addition, source of control was another possible source for both HLA-DR3 and HLA-DR15 polymorphisms, with observable significance for HLA-DR3 in only population-based studies (OR: 1.65, 95% CI: 1.370-1.990, P = 0.244) and for HLA-DR15 in both population-based and hospital-based studies (OR: 1.38,95% CI: 1.078-1.760, P=0.123 and OR: 2.08, 95% CI: 1.738-2.490,P=0.881,respectively). Conclusions: HLA-D RBI gene may be a SLE-susceptibility gene, and it shows evident ethnic heterogeneity. Further prospective validations across multiple ethnical groups are warranted.
护理预警体系在院内静脉血栓栓塞症防治中的构建与效果评价

对比2016年至2017年我院院内静脉血栓栓塞症新增病例及新发病例数,结果显示,2017年护理预警实施后全院住院患者静脉血栓栓塞症和肺血栓栓塞症新增病例减少( P = 0.001), 深静脉血栓形成和静脉血栓栓塞症新发病例亦有下降( P = 0.01, P = 0.03) 。建立以护理为主导的静脉血栓栓塞症预警管理体系,能够充分发挥临床护士的主观能动作用,提高院内静脉血栓栓塞症防治管理水平,减少住院患者静脉血栓栓塞症事件的发生,特别是对减少深静脉血栓形成的发生具有显著意义。
2007—2015年天津市居民脑卒中发病和死亡流行特征

2015年,我国每年新发脑血管病患者约270万,且呈持续上升趋势,脑卒中是中国居民第一位死因,其带来的疾病负担已成为中国疾病中的第一位.1990-2013年中国脑卒中标化死亡率呈下降趋势,由199.7/10万降到157.3/ 10万,其中脑梗死上升了28.8%,而脑出血则下降了37.7%;而对于发病趋势仅限于某些市级层面的描述(如深圳市),为了解脑卒中的发病趋势,需要更多的数据支持.此外,在慢性病研究中,常以死亡发病比作为评价登记数据完整性的指标;目前,对脑卒中死亡发病比的研究并不多,仅局限于某些市的结果,因此,有必要采用天津市20多年脑卒中发病监测系统对脑卒中的死亡发病比进行研究.
Quasinormal Modes of the Planar Black Holes of a Particular Lovelock Theory

In this work, we study the scalar quasinormal modes of a planar black hole metric in asymptotic anti-de Sitter spacetime derived from a particular Lovelock theory. The quasinormal frequencies are evaluated by adopting the Horowitz-Hubeny method as well as a matrix formalism. Also, the temporal evolution of small perturbations is studied by using finite difference method. The roles of the dimension of the spacetime, the parameter of the metric k, as well as the temperature of the background black hole, are discussed. It is observed that the particular form of the metric leads to quasinormal frequencies whose real parts are numerically insignificant. The black hole metric is found to be stable against small scalar perturbations.
T型腹膜囊袋固定术治疗游走脾二例

对于游走脾的治疗,主要有脾切除和脾固定术.随着对脾脏功能的认识,对于合并扭转坏死的采用脾切除术,对于没有扭转或者没有坏死的一般采用脾固定术.因儿童脾切除后易引起凶险性感染,特别是在4 ~5岁以下儿童,应尽量保脾或部分脾切除,也可采用自体脾移植.脾固定术有多种方法,包括直接缝合脾脏或用一个可吸收的网套支持,固定于横膈和前腹壁;将脾脏置于后腹膜小袋;缝合脾门至脾床;结肠置于脾脏前方,同时将为固定于前腹壁等.我们采用"T”型腹膜囊袋固定术治疗游走脾2例,手术顺利,术后及随访效果满意.术中需要根据脾脏大小决定囊袋的大小.对较大的脾脏,腹膜后囊袋要尽可能的大,位置尽量靠近正常脾窝处,可以自侧腹膜开始游离,直至后腹膜,可以向中线和下放延伸,注意紧贴腹膜,避免损伤血管出血.由于囊袋内放置有脾脏,对囊袋有压迫作用,一般不需要放置引流管.该手术方法具有以下优势:(1)游离侧腹膜至后腹膜,形成腹膜囊袋,范围大,可将较大的脾脏置于囊袋内;(2)将整个脾脏装进腹膜囊袋内固定,手术效果可靠,有效的避免了再次移位和扭转;(3)脾蒂从"T"型切口的横切口内经过,留有足够大的脾蒂血管通道再进行缝合固定,既起到了脾脏的固定作用,又避免了腹膜囊袋对脾蒂的压迫,使脾脏血运不受影响.