盐酸小檗碱对体外培养人牙周膜细胞炎性反应影响的初步分析

目的:研究盐酸小檗碱(Ber)作用于体外培养的人牙周膜细胞(PDLCs),在脂多糖(LPS)刺激下,合成和分泌前列腺素E2(PGE2)、白细胞介素-1β(IL-1β)和白细胞介素-6(IL-6)的变化,初步推断Ber对牙周炎的治疗作用.方法:将体外培养的PDLCs根据加入LPS与否设定为NLPS和LPS两大组,再根据培养液中Ber终浓度0μmL、5μg/mL、10μg/mL和20μg/mL将其分为NLPS0、NLPS1、NLPS2、NLPS3以及LPS0、LPS1 、LPS2和LPS3共八个组,用ELISA法检测上清液中PGE2、IL-1β和IL-6的浓度.结果:培养48h后,各组PGE2、IL-6和IL-1β有一定的表达量,NLPS各组该三者表达的差异无统计学意义(P＞0.05);加入LPS后,LPSO组上清液中PGB、1L-1β和IL-6表达明显升高,与NLPS各组之间差异具有统计学意义(P＜0.05);在加入LPS的同时加入Ber后与LPS0组比较PGE2、IL-1β和IL-6表达明显下降(P＜ 0.05);PGE2表达,LPS各组差异具有统计学意义(P＜0.05),其中除LPS3以外.其他LPS组与NLPS各对应组差异具有统计学意义(P＜ 0.05);IL-1β表达,LPSO与其他LPS组差异有统计学意义(P＜0.05),而LPS1、LPS2和LPS3之间差异无统计学意义(P＞0.05),且该三组与NLPS对应组之间差异无统计学意义(P＞0.05);IL-6表达,随着Ber浓度升高,各LPS组表达逐渐降低(P＜0.05),且与对应NLPS组差异有统计学意义(P＜0.05).结论:Ber可以抑制LPS刺激体外培养的PDLCs产生的炎性反应.     

海藻多糖对小鼠骨髓放射性急性损伤的保护作用

目的 :观察中药海藻多糖对小鼠骨髓放射性急性损伤的保护作用。方法 :检测小鼠骨髓有核细胞总数、DNA含量及嗜多色性红细胞微核率。结果 :小鼠接受 2 Gyγ射线照射后 ,小鼠骨髓有核细胞总数、DNA含量明显降低 (P<0 .0 1) ,骨髓嗜多色性红细胞微核率明显升高 (P<0 .0 1) ;2 0、40 mg/kg剂量的海藻多糖能有效防止照射小鼠骨髓有核细胞总数、DNA含量降低 (P<0 .0 5 ) ;10、2 0、40 mg/kg剂量的海藻多糖能防止照射小鼠骨髓嗜多色性红细胞微核率升高 (P<0 .0 5 )。结论 :中药海藻多糖预防性给药对小鼠骨髓放射性急性损伤有一定的保护作用     

氦氖激光照射对兔正畸牙周组织中胰岛素样生长因子-1(IGP-1)的表达影响

目的:研究氦氖激光对兔正畸牙周组织胰岛素样生长因子-I(1GF-1)表达的影响。方法:选择体重(1.5±0.2)Kg的健康的日本大耳白兔,随机分为1、3、5、7、14、21d组,每组3只,共18只。建立正畸牙移动模型,对实验动物右上颌第一磨牙相应的颊部进行氦氖激光照射,左侧为对照侧,自身对照研究。于标本处理后,进行IGF-1的免疫组化染色;对染色结果进行图象分析与统计学分析。结果:氦氖激光照射侧IGF-1免疫组化染色阳性细胞数量在张力区的表达均高于对照侧,3天、5天及7天组张力区IGF-1的表达与对照侧差异性显著;在照射侧和对照侧的压力区IGF-1的表达未见显著性差异。结论:氦氖激光照射明显促进了IGF-1在兔正畸牙周组织张力区的表达。     

~(60)C_oγ射线辐射小鼠肠壁屏障及脾T淋巴细胞增殖活性改变的观察

目的 :探讨6 0 Co 线照射小鼠肠壁机械屏障及免疫损伤状况 ,为放射损伤后内源性感染的防治提供实验资料。方法 :3 0只小鼠随机分成三组 ,分别为Ⅰ ( 0Gy)、Ⅱ ( 4 5Gy)和Ⅲ ( 6 0Gy)组。于全身一次性照射后第 9天行HE染色观察肠壁病理组织学改变 ,同时采用MTT法检测脾T淋巴细胞的增殖活性。结论 :( 1)组织学观察发现6 0 Co 线照射组肠粘膜轻度充血 ,细胞连接疏松 ;( 2 )不同照射剂量组小鼠脾T淋巴细胞增殖活性均较对照组显著下降 ,且随照射剂量增大 ,增殖活性明显下降。结论 :6 0 Co 射线照射小鼠肠壁机械屏障及脾T淋巴细胞增殖功能的受损为其内源性感染创造了条件和机会。     

^60Coγ射线辐射小鼠肠壁屏障及脾T淋巴细胞增殖活性改变的观察

目的：探讨^60Coγ线照射小鼠肠壁机械屏障及免疫损伤状况,为放射损伤后内源性感染的防治提供实验资料,方法：30只小鼠随机分成三组,分别为Ⅰ（0Gy)、Ⅱ(4.5Gy)和Ⅲ（6.0Gy)组,于全身一次性照射后第9天行HE染色观察肠壁病理组织学改变,同时采用MTT法检测脾T淋巴细胞的增殖活性。结论：（1）组织学观察发现^60Coγ线照射组肠粘膜轻度充血,细胞连接疏松;（2）不同照射剂量组小鼠脾T淋巴细胞增殖活性均较对照组显著下降,且随照射剂量增大,增殖活性明显下降。结论：^60Goγ射线照射小鼠肠壁机械屏障及脾T淋巴细胞增殖功能的受损为其内源性感染创造了条件和机会。     

氦氖激光照射胸腺区促进荷瘤小鼠T细胞的CD59表达与活化信号转导

探讨低功率氦氖激光照射对荷瘤小鼠T细胞CD59表达及其功能的影响.将(BALB/C)小鼠分为4组:Ⅰ组不做处理;Ⅱ组仅致瘤;Ⅲ组致瘤后每日照射胸腺区;Ⅳ组致瘤后隔日照射胸腺区.致瘤后第20天处死小鼠,分离培养胸腺T细胞.采用噻唑蓝(MTT)比色法测T细胞增殖,用免疫组化和免疫荧光测T细胞CD59表达量,然后用酶联免疫吸附测定法(ELISA)测T细胞活化后白介素2(IL-2)水平.用激光共聚焦测T细胞胞浆内钙离子变化,以及用流式细胞术测T细胞活化为CD+29T细胞的能力.结果表明,照射组肿瘤生长受抑;荷瘤组T细胞的CD59表达量、白介素2水平、增殖能力、钙离子浓度及活化的CD+25T细胞水平均低于正常组,但照射组明显高于非照射组.由此可见,激光照射促进了荷瘤小鼠T细胞CD59的表达,增强了其活化信号的转导.     

IL-6干预对3T3-L1脂肪细胞SAA表达的影响

目的观察IL-6干预对3T3-L1脂肪细胞血清淀粉样蛋白A(SAA)表达的影响。方法用不同浓度IL-6(0.1ng/ml,1ng/ml,10ng/ml)处理3T3-L1脂肪细胞24h、10ng/mlIL-6处理不同时间(6h、12h、24h),用ELISA技术检测各组SAA的表达。结果TNF-a能显著促进3T3-L1脂肪细胞SAA的表达,并呈剂量和时间依赖方式。结论IL-6可以通过促进3T3-L1脂肪细胞SAA的表达和分泌,参与胰岛素抵抗及血管并发症的形成。     

激光照射对脊髓损伤大鼠TNF-α、IL-6和IL-10表达的影响

应用Allen造模法制备大鼠急性脊髓损伤(SCI)模型,研究弱激光照射对损伤脊髓组织内肿瘤坏死因子α(TNF-α)、白介素-6(IL-6)和白介素-10(IL-10)表达的影响。68只SD大鼠随机分为正常组、SCI组和照射组,照射组应用810nm弱激光经皮照射相应的脊髓损伤节段。分别于术后1d、3d和7d进行BBB评分;1h、3h、6h、12h、1d、3d、5d和7d取材,酶联免疫吸附检测(ELISA)法检测受损脊髓组织内TNF-α、IL-6和IL-10的表达情况。实验发现,照射后7d照射组大鼠BBB评分高于SCI组,且有统计学意义(P0.05);与SCI组相比,照射组受损脊髓组织内TNF-α和IL-6的表达量均降低,且在术后6h、12h、1d(TNF-α)和6h、12h、5d(IL-6)差异有统计学意义(P0.05);IL-10的表达量在各个时间点均增高,且在术后1d、3d、5d和7d差异有统计学意义(P0.05)。结果表明弱激光照射能明显抑制脊髓损伤早期前炎症因子TNF-α和IL-6的表达,促进抑炎因子IL-10的表达,促进损伤后期大鼠运动功能的恢复。     

三氧化二砷对照射后人肺癌细胞MGMT和VEGF表达的影响

目的：本文探讨三氧化二砷（Arsenic trioxide,As2O3）对受照后人肺癌A2细胞株MGMT和VEGF表达的影响。方法：设立空白对照组、照射组（直线加速器X射线照射,2Gy）、As2O3组（1.0μmol/L As2O3）、As2O3＋照射组（1.0μmol/L As2O3＋X射线照射,2Gy）。平板克隆形成试验测定各实验组细胞集落形成率,用RT-PCR和免疫组化检测MGMT（甲基鸟嘌呤甲基转移酶）、VEGF（血管内皮生长因子）基因和蛋白水平的变化。结果：As2O3＋照射组细胞集落形成率较As2O3组及照射组明显下降,与As2O3组或照射组比较差异具有显著性（P〈0.01）。As2O3＋照射组细胞MGMT、VEGF基因表达明显减少,而且MGMT、VEGF蛋白的表达明显降低,与As2O3组或照射组比较差异具有显著性（P〈0.01）。结论：As2O3能使受照后人肺癌A2细胞MGMT、VEGF基因及蛋白表达水平明显下调,可能是As2O3对人肺癌细胞辐射增敏的机制之一。     

超声微泡介导野生型P53基因转染鼠视网膜母细胞瘤的实验研究

目的:探讨超声微泡造影剂在一定强度的超声波照射下介导野生型p53(wtp53)基因转染荷瘤小鼠的可行性,为实现外源基因高效,定向的转移目的奠定基础。方法:将12只BAlB/C(nu/nu)裸小鼠双眼玻璃体腔接种HXO-Rb44细胞,造模成功后,将动物随机分为2组,第1组于尾静脉注入含质粒的微泡造影剂;第2组尾静脉注射质粒与微泡的混合液,并立即以0.5W/cm2〔1〕的超声波辐照小鼠眼球60s,工作时间控制为20%。转染7天后,处死动物,摘除眼球,RT-PCR检测wtp53基因的表达情况。结果:超声照射组动物的肿瘤组织中均检测到wtp53的mRNA表达,而未照射组动物肿瘤组织中未检测到mRNA的表达。结论:超声微泡能使外源基因wtp53高效的转染小鼠RB肿瘤组织。     

AFM observation of OMVPE grown ErP on InP (0 0 1), (1 1 1)A and (1 1 1)B substrates

ErP has been grown on InP (0 0 1), (1 1 1)A and (1 1 1)B substrates by low-pressure organometallic vapor-phase epitaxy. The morphological change with growth temperature has been explored by atomic force microscope. On all the substrates, ErP is grown in island structure. Height and area size of the ErP islands on (1 1 1)A substrate exhibit an obvious dependence on growth temperature. ErP islands grown at 540°C, that is the suitable temperature for ErP formation, gather to step edges to make wires.     

Reliability of a consecutivek-out-of-r-from-n:F system

The reliability of the consecutive k-out-of-r-from-n:F system is studied. For k=2 an explicit solution is given for n components in line or in cycle in the i.i.d. case. For k⩾3 sharp lower and upper bounds are given for the reliability of the system and demonstrated for different values of n, k, r, p. These bounds are exact for r=n, n-1, n-2, n-3, and for these values the exact analytic solution is also given     

Distribution of the lifetime of consecutive k-within-m-out-of-n:F systems

The distribution of the lifetime (MTTF) of any consecutive k -within-m-out-of-n:F system, with independent exponentially distributed component lifetimes, is shown to be a convex combination of the distributions (MTTFs) of several convolutions of independent random variables, where each convolution represents a distinct path in the evolution of the system's history, and where in each convolution all but the last random variable is exponential. The last random variable in each convolution is either a zero lifetime or the lifetime of several disjoint consecutive k_i within m_i-out-of-n:F systems in series with each k_i<k, each m_i<m, and each n_i<n. This enables the calculations to proceed recursively. Calculations are facilitated by the symmetric nature of the convex combination     

Bounds for reliability of consecutivek-within-m-out-of-n:F systems

Upper and lower bounds for the reliability of a (linear or circular) consecutive k-within-m-out-of-n:F system with unequal component-failure probabilities are provided. Numerical calculations indicate that, for systems with components of good enough reliability, these bounds quite adequately estimate system reliability. The estimate is easy to calculate, having computational complexity O(m²×n). For identically distributed components, a Weibull limit theorem for system time-to-failure is proved     

Analysis of coplanar E-H planeT-junction using dissimilar rectangular waveguides

An analysis of a T-junction that differs from conventional H -plane T-junctions in that the T arm is rotated by 90° and coupling takes place through an inclined slot is presented. Since use of standard X-band waveguides results in such a T-junction operating above 11.7 GHz, nonstandard waveguide dimensions have been considered to bring down the operating frequency to 9.375 GHz. The effect of a change of the broad dimension of the primary feed waveguide on the resonant conductance is evaluated. The variations of resonant length with the angle of inclination of the slot, and coupling with frequency, are presented     

Electrochemical C-V profiling of heterojunctiondevice structures

Electrochemical capacitance-voltage profiles of multiple (In,Al) GaAs heterostructures have been measured and compared with the results of a numerical calculation of the apparent charge density based on a one-dimensional Poisson solver. The calculation, using layer thicknesses, dopings, and heterojunction band discontinuities obtained from MBE growth calibrations, is in overall agreement with the measured data. The largest discrepancy occurs between the expected and measured heterojunction band discontinuity. This difference is consistent with an electrolyte/semiconductor interface which is not planar on a scale comparable to the layer thickness     

Optimum control of N-input K-output matrixconverters

Significant developments of the general optimum control theory presented in a previous paper by the authors (1988) are discussed for the specific case of multiphase matrix converters. Results hold, regardless of system configuration, input and output voltage waveforms, and loads. Applications to the most practical converter structures are illustrated, and implementation criteria of the optimum control method are derived. Simulated results confirm the flexibility and effectiveness of the approach     

A generalization of consecutive-k-out-of-n:Fsystems

A linear (m, n)-lattice system consists of m ·n elements arranged like the elements of a (m ,n)-matrix, i.e. each of the m rows includes m elements, and each of the n columns includes m elements. A circular (m,n)-lattice system consists of m circles (centered at the same point) and n rays. The intersections of the circle and the rays represent the elements, i.e. each of the circles includes n elements and each of the rays has m elements. A (linear or circular) (m, n)-lattice system is a (linear or circular) connected-X-out-of-(m,n):F lattice system if it fails whenever at least one subset of connected failed components occurs which includes failed components connected in the meaning of connected-X. The paper presents some practical examples and the reliability formulas of simple systems using results of consecutive-k-out-of-n:F systems     

A technique for real-time measurement of Nth-orderderivativesdNV/dIN

A technique for the measurement of device derivatives d ^NV/dI^N of arbitrary order N described. Measurement is accomplished by injecting a test current composed of the sum of N square waves into the rest device, and then multiplying the corresponding voltage change by the product of those same square waves, followed by low-pass filtering. The algorithm is implemented in real time using a mixture of analog and digital circuitry, and its application to semiconductor laser control in high-speed optical communications is described     

Reliability of a k-out-of-n warm-standby system

A general closed-form equation is developed for system reliability of a k-out-of-n warm-standby system (dormant failures). The equation reduces to the hot and cold standby cases under the appropriate restrictions