摆动筛运动的数学分析

本文分析了摆动筛的运动规律,并计算了位移、速度和加速度,分析了筛面上颗粒物体的受力情况,可供设计、制造和使用作参考。     

Mechanism of testicular atrophy induced by di-n-butyl phthalate in rats. Part 1

Repeated oral doses of di-n-butyl phthalate (DBP) to male rats caused a decrease in testicular fructose and glucose and a sloughing of the germ cells on the first day of treatment. On day 2, more severe sloughing was seen and was accompanied by decreases in testicular iron and zinc levels and increases in the level of inositol and cholesterols. The sloughing was followed by atrophy, accompanied by dissociation of the germ cells from the Sertoli cells and reduction of triglycerides, cholesterols and phospholipids containing choline and ethanolamine residues in the testis.     

肾盏切开联合经肾实质气压弹道碎石治疗复杂鹿角形结石

目的探讨肾盏切开联合经肾实质气压弹道碎石治疗复杂鹿角形结石的疗效。方法电刀切开积水较重的肾盏,气压弹道碎石杆对准结石碎石后分块取出。盏颈口狭窄但肾盏积水不严重者,将直径1 mm气压弹道碎石杆于肾实质处刺入结石位置,将肾盏内结石击碎后从盏颈口取出。结果19例均未阻断肾蒂,手术时间90-150 min,平均120 min。术中出血量100-250 ml,未输血。17例一次取石成功,术后无结石残余;1例术中残余泥沙状结石,术后经肾造瘘管冲洗引流排出;1例肾盏结石术中取石遗漏,术后经ESWL碎石后排净结石。15例随访10-60个月,平均18个月,结石复发2例,体外震波碎石后排净结石。结论肾盏切开联合经肾实质气压弹道碎石治疗复杂性鹿角形结石出血少,疗效可靠。     

电脑比配色仪与比色板之间的相近性分析

目的：通过对比色记录的分析，比较Vita比色板、松风Vintage Halo比色板和电脑比配色仪之间的相近性和差异性。方法：随机抽取100名年龄在21～24岁的本地在校大学生，由男女两位测试者使用电脑比配色仪、Vita比色板和松风Vintage Halo比色板对被测试者的左上中切牙进行比色分析。结果：三种比色方法均以A色调最为集中，占总数的55％以上。其次是D色调占总数20％以上。男女测试者的选色在A、R、VR．系列中无明显差异。结论：电脑比配色仪、Vita比色板、松风Vintage Halo比色板均不能完全覆盖本地区青年天然中切牙的色度特征，只在A色调系列中重复率较高。     

尿流改道及膀胱重建术的现状与展望

膀胱全切术后尿液的贮存与排出一直是未能满意解决的问题。自从1852年Simon报道输尿管乙状结肠吻合以来，经过一个多世纪的不断改进与创新，特别是1982年Kock用去管重建法制作贮尿囊的可控膀胱以来，尿流改道与膀胱重建术有了跨时代的进步和发展，显地提高了患术后生活质量。     

PFT-α对结肠上皮细胞凋亡和周期的影响及机制探讨

目的探讨p53抑制剂（p-fifty three inhibitor—alpha，PFT-α）对结肠上皮细胞凋亡、周期的影响及机制。研究PFT-α对热化疗损伤结肠上皮细胞的影响。方法顺铂联合温热处理原代培养结肠七皮细胞30min，对比加入不同浓度PFT-α后，Annexin V—FITC／PI染色，流式细胞仪检测细胞凋亡。PI染色检测细胞周期。Western blot检测结肠上皮细胞Cyclin B1和Cdc2（Tyr15）表达。结果不同浓度PFT-α作用于热化疗处理的结肠上皮细胞后，细胞凋亡率下降且呈剂量依赖性。流式细胞仪细胞周期分析显示在运用PFT-α后，结肠上皮细胞的G2／M延长，CyclinB1和Cde2（Tyr15）蛋白表达随PFT—α的剂量升高而逐渐增强。结论PFT-α可能通过促进CyclinB1蛋白表达，Cde2（Tyr15）磷酸化水平升高，降低CyclinB1／Cde2活性，细胞停滞于G2／M期，减轻热化疗对结肠上皮细胞的损伤。     

骨髓输液在PICU的应用探讨

目的　探讨骨髓输液在PICU的适应证、方法及临床效果。方法　选择PICU危重症建立静脉通道困难患儿 30例 ,采用 7号骨穿针或 7～ 9号头皮针于胫骨粗隆下 1～ 2cm穿刺、固定 ,接入医嘱液体 ,记录穿刺所需时间、入液速度及生命体征变化、并发症等。结果　 2 8例 1次成功 ,2例用头皮针者有堵塞 ,换针后重新穿刺成功 ,穿刺、固定到接入液体平均时间 (30± 10 )s。速率 :一般压力 (8± 3)ml (kg体重·h) ,加压下 (17± 6 )ml (kg体重·h) ,所有病例均达到了医嘱要求。骨髓输液持续时间 3～ 2 2h ,无 1例出现并发症。结论　骨髓输液在PICU危重症抢救中可迅速建立液体通道 ,争取抢救时间。头皮针比骨髓穿刺针易于固定 ,使用更方便     

A cyclic peptide–polymer probe for the detection of Clostridium botulinum neurotoxin serotype A

A Botulinum neurotoxin serotype A (BoNT/A) ELISA detection system was developed based upon an 11-mer cyclic peptide, termed C11-019, that was identified through peptide phage display technology. The assay employs a sandwich format using the C11-019 cyclic peptide attached to a PEMA (poly(ethylene maleic anhydride)) matrix as the capture phase and anti-BoNT/A polyclonal antibodies as the detection phase. Results reported demonstrate that the C11-019 peptide–polymer can specifically bind to BoNT/A with no cross-reactivity to other serotypes examined in assay buffers and a variety of body fluids and foodstuffs. When a highly sensitive chemiluminescent substrate was engaged, the detection of 1 pg/mL could be readily achieved within 3 h with a linear range of 0.1–1 ng/mL. These results demonstrate that an inexpensive peptide–polymer-based capture ELISA system can be used for rapid, sensitive and highly specific BoNT detection.     

高频超声引导定位前臂浅静脉穿刺

目的探讨高频超声引导定位穿刺前臂浅静脉的应用价值。方法对40例常规浅静脉穿刺失败，采用高频探头在同一体表区域寻找并标记浅静脉走行及深度，确认进针方向后再次静脉穿刺，必要时采用实时引导。结果11例经高频超声标记、29例经高频超声实时引导静脉穿刺均一次成功。结论高频超声引导下静脉穿刺的成功率高，无并发症，是一种简便有效的方法，值得在临床推广应用。     

A comparative study of using comet assay and gammaH2AX foci formation in the detection of N-methyl-N'-nitro-N-nitrosoguanidine-induced DNA damage.

Comet assay is a useful technique in the detection of DNA damages, particularly DNA strand breaks; and it has been utilized to show that a potent carcinogen N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), can induce such damages. Recently, gammaH2AX foci formation has been suggested as another sensitive way to detect DNA double strand breaks (DSBs). However, there is no systematic comparison being conducted to evaluate the consistency of these two methods. Using MNNG as a model chemical, the sensitivity of neutral comet assay and gammaH2AX foci formation in detecting MNNG-induced damage was studied. It was found that at concentrations of 0.1 and 1 microg/ml, both methods can detect MNNG-induced damage in human amnion FL cells. However, at 0.1 microg/ml, comet assay revealed more percentage of cells with DNA damage than gammaH2AX fluorescence revealed. On the other hand, while gammaH2AX foci were readily formed at very early times by 10 microg/ml MNNG treatment, neutral comet assay did not detect any significant DNA damage at the same time points. In addition, 10 microg/ml MNNG induced a distinct whole nuclei staining pattern of gammaH2AX, a type of DNA damage which was not detected by neutral comet assay but could be detected by alkaline comet assay. Therefore, gammaH2AX may be used as a sensitive indicator for DNA damage.