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     

环境极低频电磁场对血液系统的影响

目的:探讨环境极低频电磁场对高校学生血液系统的影响.方法:参照《辐射环境保护管理导则》(HJ/T10-1996)对重庆某大学进行环境极低频电磁场监测,以监测结果为分组标准,将重庆某大学老校区学生537人设为观察组,以该校新校区学生516人为对照组.组织问卷调查了解血液系统相关疾病自主症状;采用全自动血液分析仪对两组学生的末梢血样本进行分析.结果:两校区电场强度和磁场强度均低于国际ICNIRP导则中相应频段的导出限值,老校区5Hz～ 1kHz频段电场和磁场强度平均值显著高于新校区(P＜0.05).观察组四肢无力发生率高于对照组(P＜0.05).观察组中性粒细胞、红细胞、红细胞压积、血红蛋白含量均高于对照组(P＜0.05),淋巴细胞计数、红细胞平均血红蛋白含量及浓度、血小板计数、血小板压积、血小板平均体积均低于对照组(P＜0.05);其中居住年限(暴露年限)与红细胞计数、血红蛋白含量呈正相关,与淋巴细胞计数呈负相关(P＜0.05).结论:相对较高水平5Hz～ 1kHz环境极低频电磁场暴露对大学生血象有弱影响,随暴露年限增加,红细胞计数、血红蛋白含量、淋巴细胞计数改变增大.     

淫羊藿苷对去卵巢快速老化小鼠(SAMP8)学习记忆及皮层氧化应激的影响

目的研究淫羊藿苷(ICA)对去卵巢雌性快速老化模型小鼠(SAMP8)学习记忆能力及抗氧化能力的影响。方法本实验以10月龄去卵巢雌性SAMP8小鼠为模型,以同月龄抗快速老化小鼠(SAMR1)为正常对照,以SAMP8假手术作为对照。实验共分为SAMR1组、SAMP8假手术组、SAMP8手术组、多奈哌齐组、己烯雌酚组、ICA75mg/kg组、ICA150mg/kg组7组。灌胃给药8周,通过Morris水迷宫检验ICA对SAMR1和SAMP8学习记忆能力的影响;测定大脑皮层中NO、MDA、SOD、GSH-Px活性。结果ICA150mg/kg、75mg/kg可明显改善OVX SAMP8定位航行潜伏期(P<0.05),提高空间探索能力,平台象限停留时间为ICA150mg/kg45.88±2.98s,ICA75mg/kg40.26±3.66s,OVX SAMP817.13±3.73s(P<0.05);可明显提高大脑皮层内SOD及GSH-Px活性(P<0.05),显著降低MDA及NO的水平(P<0.05)。结论ICA可以改善OVX SAMP8的学习记忆能力,可显著提高OVX SAMP8抗氧化能力。     

He-Ne激光照射的安全性

用功率为15～80 mW的He—Ne激光,以人的治疗剂量照射家兔,结果从所观察的各项卵巢内分泌和生殖功能的指标的变化,与对照组间的差别不显著(P>0.05)。观察各组剂量照射后的遗传毒性效应,结果各实验组的微核率均在正常范围以内,与空白对照组间的差别不显著(P>0.05),而与CTX阳性对照组间的差别极显著(P<0.01)。动物实验与临床观察一致,提示目前应用的各级治疗剂量均属于低功率,从卵巢功能和细胞遗传效应来说是比较安全的。     

牛磺酸对顺铂引起的小鼠肾髓质ATP酶活性变化的影响

目的 :探讨牛磺酸对顺铂引起的小鼠肾髓质ATP酶活性的影响 ;方法 :4 0只小鼠随机分为正常对照组、CDDP组、牛磺酸 2 0 0mg组 (Tau2 0 0 )和牛磺酸 4 0 0mg组 (Tau4 0 0 ) ,分取肾髓质、制备匀浆 ,用生化法测定Na ,K -ATP酶、Ca2 -ATP酶和Mg2 -ATP酶活性 ;结果 :CDDP组、Tau2 0 0组、Tau4 0 0组肾髓质Na ,K -ATP酶、Ca2 -ATP酶和Mg2 -ATP酶活性均明显低于正常对照组 (P <0 .0 1)。Tau2 0 0组、Tau4 0 0组肾髓质Na ,K -ATP酶和Ca2 -ATP酶活性均明显高于CDDP组 (P <0 .0 1或P <0 .0 5 ) ,而Mg2 -ATP酶活性与CDDP组相比无显著差别 (P >0 .0 5 ) ;结论 :牛磺酸可明显增加肾髓质Na ,K -ATP酶和Ca2 -ATP酶活性 ,对顺铂引起的肾毒性具有防治作用。     

半导体激光联合电针及康复干预治疗周围性面神经炎的疗效观察

目的:观察半导体低强度激光联合电针及康复干预治疗周围性面神经炎的临床疗效。方法:将急性周围性面神经炎患者76例,随机分成对照组和观察组各38例。对照组给予电针加早期康复干预;观察组在此基础上加用半导体激光仪照射治疗。评价治疗前后两组患者面神经功能及治疗后其临床疗效。结果:干预3周后,两组患者面神经功能评分均比治疗前明显提高(P<0.05);且观察组更高于对照组(P<0.05);干预后,两组疗效有显著差异(P相似文献   

小儿先心病中EEG和RAEP的临床评价

目的 :评价先心病儿脑电图 (EEG)、脑干听觉诱发电位 (BAEP)的变化。方法 :对 3 0例先心病儿童EEG、BAEP的变化进行对比观察 ,并以 3 0名健康儿童为对照组。结果 :1.EEG :发绀组 (CCHD)异常率为 80 %( 8/ 10 ) ,非发绀组 (NCCHD)异常率为 3 0 %( 6/ 2 0 ) ,差异显著 (P <0 .0 5 )。2 .BAEP :CCHD组异常率为 10 0 %( 10 / 10 ) ,NCCHD异常率为 65 %( 13 / 2 0 ) ,差异显著 (P<0 .0 5 ) ,Ⅴ波潜伏期 (PL)、Ⅲ -Ⅴ、Ⅰ -Ⅴ波峰间潜伏期 (IPL)先心病患儿与对照组比较 ,CCHD组显著延长 (P <0 .0 5 )。 3 .EEG与BAEP :EEG异常者BAEP均异常 ( 10 0 %) ,EEG正常者BAEP有 5 6.3 %异常。结论 :1、先心病患儿伴有脑功能异常 ,CCHD较NCCHD显著。 2、EEG与BAEP均可反映脑功能异常改变 ,但非完全同步 ,BAEP似乎较为敏感。     

重型α地中海贫血红细胞的拉曼光谱

采用光镊拉曼光谱(LTRS)方法收集一例重型α地中海贫血患者单个红细胞的拉曼光谱,分析同一群体内不同细胞间的光谱差异,从中了解地中海贫血红细胞的病理过程.结果发现,重型α地中海贫血患者红细胞的拉曼光谱信号显著低于正常对照,并检测到一定比例的有核红细胞;正常对照的红细胞拉曼光谱均一,而重型α地中海贫血患者的细胞形态和拉曼光谱均显示出多样性;中等大小、形态接近正常的一类红细胞,其细胞问光谱差异最大;单细胞拉曼光谱可观察到部分外表形态正常的红细胞,其血红蛋白可能发生了血红素凝集和蛋白质变性.     

光动力疗法对Louis肺癌鼠的杀伤及免疫效应

应用光动力疗法对 30只接种Louis肺癌瘤株的昆明小鼠作杀伤实验研究。对实验组与对照组荷瘤鼠抑瘤曲线、抑瘤率及免疫学指标进行检测。结果表明 ,两组肿瘤生长曲线存在明显差异 (P<0 0 5 )。两组肿瘤生长体积和肿瘤重量均存在明显差异 (P <0 0 1)。实验组瘤体积抑制率为 5 2 94 % ,瘤重量抑制率为 37 2 4 %。各免疫指标与对照组差异有显著性。说明光动力疗法对肿瘤细胞具有杀伤和抑制生长作用 ,并且对荷瘤小鼠的免疫功能有调节作用     

窄谱中波紫外线联合卤米松对寻常型白癜风患者皮肤炎症及黑素细胞功能的影响

探讨窄谱中波紫外线(NV-UVB)联合卤米松对 寻常型白癜风患者皮肤炎症及黑素细胞(MC)功能的影响。方法:选取2017年1月至2018年12月本院100例寻常型白癜风患 者,依据随机数字表分为A组和B组,每组50例,B组给予0.05%卤米松治疗,A组在此基础上 联合NV-UVB治疗,比较两组皮肤炎症[白介素(IL)-2、IL-17、IL-22]、MC功能[MC 、α-黑 色素细胞刺激素(α-MSH)]、治疗疗效、不良反应。结果:A组和B组治疗后IL-2、IL- 17、 IL-22明显低于治疗前,A组治疗后IL-2、IL-17、IL-22明显低于B组,有统计学差异(P<0.05);A组和B组治疗后MC、α-MSH 明显高于治疗前,A组治疗后MC、α-MSH明显高于B组,有 统计学差异(P<0.05);A组治疗有效率 为94.00%,明显高于B组的80.00%,有统计学 差异(P<0.05);B组和A组不良反应率为10.00%和14.00%,两组比较无统计学差异(P>0.05)。结 论:NV-UVB联合卤米松可有效改善寻常型白癜风患者皮肤炎症及MC功能,有利于提高患者 的治疗疗效,且安全性好,值得临床推广。     

Compression Stress–Strain Behavior of Sn-Ag-Cu Solders

New Pb-free alloys that are variations of the Sn-Ag-Cu (SAC) ternary system, having reduced Ag content, are being developed to address the poor shock load survivability of current SAC305, SAC396, and SAC405 compositions. However, the thermal mechanical fatigue properties must be determined for the new alloys in order to develop constitutive models for predicting solder joint fatigue. A long-term study was initiated to investigate the time-independent (stress–strain) and time-dependent (creep) deformation properties of the alloy 98.5Sn-1.0Ag-0.5Cu (wt.% SAC105). The compression stress–strain properties, which are reported herein, were obtained for the solder in as-cast and aged conditions. The test temperatures were −25°C, 25°C, 75°C, 125°C, and 160°C and the strain rates were 4.2 × 10⁻⁵ s⁻¹ and 8.3 × 10⁻⁴ s⁻¹. The SAC105 performance was compared with that of the 95.5Sn-3.9Ag-0.6Cu (SAC396) solder. Like the SAC396 solder, the SAC105 microstructure exhibited only small microstructural changes after deformation. The stress–strain curves showed work-hardening behavior that diminished with increased temperature to a degree that indicated dynamic recrystallization activity. The aging treatment had a small effect on the stress–strain curves, increasing the degree of work hardening. The yield stresses of SAC105 were significantly less than those of SAC396. The aging treatment caused a small drop in yield stress, as is observed with the SAC396 material. The static modulus values of SAC105 were lower than those of SAC396 and exhibited both temperature and aging treatment dependencies that differed from those of the SAC396 material. These trends clearly show that the stress–strain behavior of Sn-Ag-Cu solders is sensitive to the specific, individual composition.     

Hemolytic resistance of erythrocytes in the development of experimental tumors

Peculiarities of variations in the mechanical resistance of erythrocytes from mice with tumours were studied depending on the growth stage of tumours (lymphoma NK/Ly and sarcoma S-37). The accumulation of erythrocytes with the increased mechanical resistance at the stage of rapid tumour development (on the 4 to 6th days) was revealed by the kinetic method of ultrasonic haemolysis. Quantitative parameters of ultrasonic haemolytic resistance of erythrocytes from normal and tumour-bearing mice were used as criteria for the red blood cell changes depending on the cell age in blood. The increase of haemolytic resistance at the rapid stage of tumour growth may be caused by a higher number of "young" erythrocytes in blood. Ultrasonic haemolytic resistance increases when there is no changes in the erythrocyte quantity and hemoglobin concentration. The kinetic study of ultrasonic haemolysis of the erythrocytes isolated from peripheric blood permits estimating the reaction of the blood forming organs to the origin and development of tumours.     

Solder joint reliability and characteristics of deformation and crack growth of Sn-Ag-Cu versus eutectic Sn-Pb on a WLP in a thermal cycling test

Sn-Ag-Cu (SAC) is now recognized as the standard lead free solder alloy for packaging interconnect in the electronics industry. This paper analyzes the performance of both SAC and eutectic Sn-Pb solder alloys on Kulicke & Soffa's (K&S') Ultra CSP/spl reg/ wafer level package (WLP) at a thermal cycling (TC) test. The Ultra CSP standard Al/Ni-V/Cu under bump metallurgy (UBM) system was used to analyze if this UBM system with SAC solder would produce acceptable reliability in the TC test. In this study, two TC tests were performed. In the first test, two parts were removed from the TC chamber about every 200 cycles to investigate the characteristics of deformation and crack growth in the SAC and eutectic Sn-Pb Ultra CSP solder joints during TC testing. These TC test results showed that both the SAC and eutectic Sn-Pb Ultra CSPs exhibited normal solder joint fatigue failures during the testing. The SAC Ultra CSP had an equal or 18% higher Weibull life than the eutectic Sn-Pb one. Based on these results it was concluded that the SAC Ultra CSP with the Al/Ni-V/Cu UBM system produces acceptable solder joint reliability in a TC test. The results also revealed that the deformation and crack growth characteristics of the SAC and eutectic Sn-Pb Ultra CSP solder joints were significantly different. The eutectic Sn-Pb solder joints showed significant inelastic shear deformation during the TC testing while the SAC solder joints did not display significant inelastic deformation even at the high temperature regime of the TC test.     

Investigation on nano-reinforced solder paste after reflow soldering part 1: Effects of nano-reinforced solder paste on melting,hardness, spreading rate,and wetting quality

In this study, the effects of three distinctive contents of metal oxide [Iron Nickel Oxide (Fe₂NiO₄), Iron Oxide (Fe₂O₃), Nickel Oxide (NiO), and Indium Tin Oxide (ITO)] and carbon nanostructure [diamond (C)]-reinforced solder paste on melting behavior, hardness, spreading rate, and wetting angle after reflow soldering were differentiated. Each nanoparticle was mechanically mixed with SAC 305 solder paste to produce homogeneous nanocomposite solder alloys. Based on the results, the addition of nanoparticles slightly increased the melting point; except for the SAC 305-ITO and SAC 305-Diamond composite solder pastes. The SAC 305-ITO composite solder showed negligible effects, but the SAC 305-Diamond composite solder reduced the melting point. The SAC 305-Diamond composite solder exhibited a very high increment in solder hardness compared with other nanocomposite solder pastes. Reinforcement of 0.5 wt% diamond nanoparticles increased solder viscosity higher than other metal oxide nanoparticles. The flow rate of SAC 305-Diamond molten solder on Cu substrate decreased upon the nanoparticle addition during reflow soldering. The reduction in the spreading caused the enlargement in the wetting angle of solder paste. However, very low percentage of carbon nanostructure addition into molten solder alloys reduced the melting point and increased solder hardness with tolerable spreading rate and wetting quality, which enhanced solder reliability after reflow.     

眼底造影荧光强度的计算机定量分析

目的 :建立眼底血管荧光造影 (fundusfluoresceinangiography ,FFA)中荧光强度定量图像分析方法 ,以评价眼底病变的病变程度和预后。方法 :分析湿性增龄性黄斑变性 (age -relatedmaculardegeneration ,AMD)患者FFA图像脉络膜新生血管膜 (choroidalneovascularizition ,CNV)渗漏强度在造影各期的变化趋势 ,分析正常眼底后极部 6.2 0mm2 区域的FFA荧光强度在造影各期的变化趋势 ,二者进行比较 ,验证荧光强度定量分析方法的客观性、有效性和实用性。结果 :湿性AMD患者的FFA图像CNV荧光素渗漏强度造影各期均显著高于正常眼底后极部 6.2 0mm2 区(P <0 .0 5或P <0 .0 1) ,动静脉期至 72 0秒差别具有非常显著性意义 (P <0 .0 1)。 180秒～ 3 0 0秒差别最明显。结论 :对眼底疾病的病变程度和预后进行评估 ,荧光强度计算机定量图像分析方法是比较客观、有用的方法     

ILLLI对银屑病患者红细胞SOD和MDA变化的影响

目的:探索ILLLI治疗对银屑病患者红细胞SOD、MDA变化的影响。方法:以氦氖激光或半导体激光ILLLI,每次照射时间 1h,功率 5mW,每天 1次,10次为一疗程,观察治疗前后银屑病患者外周血红细胞SOD、MDA变化,并与正常人的结果作对比。结果:银屑病各组红细胞SOD含量在治疗前无显著差异,均低于正常对照组,正常对照组SOD平均高出患者2.6倍,统计学分析差异有显著性,p<0.05,治疗后,各组SOD含量均有明显上升,平均上升近2倍之多,p<0.05,且接近正常对照组,p>0.05。银屑病各组红细胞MDA含量在治疗前无明显差别,均高于正常对照组,平均高出正常人近2.4倍,差异有显著性,p<0.05,治疗后,各组MDA含量均有明显下降,平均下降近1倍,有统计学差异,p<0.05,但未恢复到正常人水平,与正常对照组之间仍存在显著性差异,p<0.05。结论:ILLLI治疗无论是He-Ne激光或是半导体激光对银屑病病员都能激活SOD,提高患者的抗氧化能力。     

Opportunistic Multi-Access: Multiuser Diversity, Relay-Aided Opportunistic Scheduling, and Traffic-Aided Smooth Admission Control

We study multi-access control in opportunistic communication systems, and propose two new schemes to address channel asymmetry and throughput-guaranteed admission control, respectively. We first devise a relay-aided opportunistic scheduling (RAOS) scheme, in which a user can choose to communicate with the base station either directly or using multiple hops (relay transmissions). We develop relay/direct link construction algorithms using either a channel-capacity-based criterion or a throughput-based criterion, and devise opportunistic scheduling schemes accordingly. Our results show that in the presence of channel asymmetry across users, the RAOS scheme performs significantly better than Qualcomm's HDR scheme. Next, we propose a traffic-aided smooth admission control (SAC) scheme that aims to guarantee throughput provisioning. Simply put, in the SAC scheme, the admission decision is spread over a trial period, by increasing gradually the amount of the time resource allocated to incoming users. Specifically, using the modified weighted proportional fair (WPF) scheduling, we devise a QoS driven weight adaptation algorithm, and the weights assigned to new users are increased in a guarded manner. Then an admission decision is made based on the measured throughput within a time-out window. A key feature is that we exploit explicitly the traffic information and throughput requirements in devising the back-off time. Our results show that the proposed SAC scheme works well in opportunistic communication systems.     

Elevated temperature aging of solder joints based on Sn-Ag-Cu: Effects on joint microstructure and shear strength

The shear strength behavior and microstructural effects after aging for 100 h and 1,000 h at 150°C are reported for near-eutectic Sn-Ag-Cu (SAC) solder joints (joining to Cu) made from Sn-3.5Ag (wt.%) and a set of SAC alloys (including Co- and Fe-modified SAC alloys). All joints in the as-soldered and 100-h aged condition experienced shear failure in a ductile manner by either uniform shear of the solder matrix (in the strongest solders) or by a more localized shear of the solder matrix adjacent to the Cu₆Sn₅ interfacial layer, consistent with other observations. After 1,000 h of aging, a level of embrittlement of the Cu₃Sn/Cu interface can be detected in some solder joints made with all of the SAC alloys and with Sn-3.5Ag, which can lead to partial debonding during shear testing. However, only ductile failure was observed in all solder joints made from the Co- and Fe-modified SAC alloys after aging for 1,000 h. Thus, the strategy of modifying a strong (high Cu content) SAC solder alloy with a substitutional alloy addition for Cu seems to be effective for producing a solder joint that retains both strength and ductility for extended isothermal aging at high temperatures.     

Thermal and mechanical effects of voids within flip chip soldering in LED packages

This paper investigates the effect of void percentage in the solder layer on the shear strength and thermal property of DA3547 packages by SAC soldering technology. X-ray observation and shear tests revealed that the increase of solder paste volume significantly decreases the void percentage in the solder layer and thus improved the shear strength of the packages. Furthermore, packages with lower void percentage showed a lower junction temperature based on the results of IR test and finite element simulation. The temperature difference due to the effect void percentage shows a correlation with the input power. For the DA3547 packages studied in this research, voids show limited influence on the junction temperature under 50 mA, the typical current recommended by Cree.