An anti-CD44 antibody does not enhance engraftment of DLA-identical marrow after low-dose total body irradiation

920 cGy total body irradiation (TBI) is adequate for consistently successful engraftment of marrow from dog leukocyte antigen (DLA)-identical littermates; however, the dose is inadequate to ensure a marrow graft from DLA-nonidentical unrelated donors. Such mismatched grafts are successful only after 1800 cGy, given in three fractions. While anti-T-cell reagents enhance engraftment of DLA-identical littermate marrow after 920 cGy, they fail to be effective in the DLA-nonidentical setting. However, a monoclonal antibody (mAb) to CD44, S5, was found to be very effective in enhancing engraftment of DLA-nonidentical marrow. The current study asked whether mAb S5 was also effective in the setting of DLA-identical littermate transplants. To this purpose, the TBI dose was lowered to 450 cGy, a dose after which 70% of such grafts failed. Four dogs were treated with antibody S5, 0.2 mg/kg on days −7 though −2 (per previously published protocol), given 450 cGy TBI followed by marrow grafts from their DLA-identical littermates. All four dogs rejected their grafts; two of these died from marrow aplasia, and two survived with endogenous marrow recovery. This result was not statistically significantly different from that in 17, historical (n = 5) and concurrent (n = 12), control dogs where 11 of 17 animals rejected. Even if ten experimental animals were transplanted and all six remaining dogs engrafted, the results still would not have been significantly different from control. This result is in contrast to the successful engraftment promoted by pretreatment with antibody S5 of DLA-nonidentical unrelated dogs, consistent with the notion that different host cells are involved in graft rejection in the two disparate histocompatibility settings.     

FRACTURE OF ABUTMENT SCREW SUPPORTING A CEMENTED IMPLANT-RETAINED PROSTHESIS WITH EXTERNAL HEXAGON CONNECTION: A CASE REPORT WITH SEM EVALUATION

One of the causes of implant failures in cemented implant-retained prostheses is the fracture of abutment screw or UCLA abutment. This article reports a case of simultaneous fracture of two UCLA abutments screws occurring in an implant-supported prosthesis placed in the mandibular molar region. The fractured structures were examined under scanning electron microscopy to investigate the probable causes of the failure, which were not related to failures on materials or fabrication of the screws, but rather were due to shear forces. The misfit in cemented prostheses may be the most likely cause of shear force generation.     

抑郁障碍患者人格特征与发病关系的研究

目的探讨抑郁障碍患者的人格特征与其疾病发病间的关系。方法采用自评抑郁量表(SDS)、艾森克人格问卷 (EPQ)、应对方式评定量表 (WCRS)和归因方式问卷 (ASQ)对 76名抑郁障碍患者进行测试 ,同时选取 84名健康被试进行对照研究。结果①抑郁组患者在EPQ中神经质 (N)与精神质 (P)的得分显著高于健康组。②WCRS的结果显示在“宣泄接纳”、“退避调节”两个因子上 ,抑郁组的平均得分低于健康组。③在ASQ的得分中 ,抑郁组在负性事件归因的自身性、持久性和整体性均显著高于健康组。④抑郁障碍患者的“神经质”人格特质与应对方式的“宣泄接纳”和“退避调节”因子呈负相关 (r = 0 .474)。结论抑郁障碍患者的人格特征可表现为较强的神经质及孤僻、交往障碍 ,他们这种人格特征及应对和归因方式在其发病过程中起着重要作用。     

99Tcm标记人源化抗人血小板膜糖蛋白Ⅲ a单克隆抗体SZ21F(ab)2血栓栓塞显像

目的用动物血栓栓塞模型显像评估99^Tc^m标记人源化抗人血小板膜糖蛋白（GP）Ⅲa单克隆抗体（简称单抗）F（ab）2片段SZ21F（ab）2的应用价值。方法通过体外抑制二磷酸腺苷（ADP）诱导的犬血小板聚集实验，评估SZ21F（ab）2与血小板结合的亲和性和特异性。以2-亚氨基噻吩盐酸盐（IT）法修饰SZ21F（ab）2分子的亚氨基，以99^Tc^m-葡庚糖酸钠（GH）转换络合法进行标记。分别用快速薄层层析（ITLC）法和ELISA测定标记物的放化纯及生物活性。对3条肺动脉血栓和8条（包括上述3条）后肢深静脉血栓栓塞比格犬模型进行显像研究。结果SZ21F（ab）2抑制ADP诱导的犬富含血小板血浆（PRP）聚集实验的半数有效剂量（IC50）为（2．49±1．88）μg／ml。ITLC法测得标记物的放化纯为90％～95％，ELISA测定结果表明标记后抗体保留了免疫活性。注射显像剂后1h，肺动脉血栓部位和后肢深静脉血栓部位均出现放射性浓聚。注射后3h，在体显像肺动脉血栓和后肢深静脉血栓栓塞模型的放射性靶／本底（T／B）比值分别为3．03±1．18和3．51±0.62。肺动脉血栓部位和后肢深静脉血栓部位的每克组织百分注射剂量率（％ID／g）分别为0．083％ID／g和0．076％ID／g。体外检测结果表明：肺动脉血栓与正常肺组织的单位质量放射性比值平均为12．8，后肢深静脉血栓与血液的单位质量放射性比值平均为5．2，与肌肉的比值平均为127.0。结论99^Tc^m-SZ21F（ab）2与人血小板具有较高的亲和力，有潜在的血栓显像应用前景。     

Selective Postsynaptic Inhibition of Tonic-firing Neurons in Substantia Gelatinosa by μ-Opioid Agonist

Background: Spinal substantia gelatinosa (SG) is a site of action of administered and endogenous opioid agonists and is an important element in the system of antinociception. However, little is known about the types of neurons serving as specific postsynaptic targets for opioid action within the SG. To study the spinal mechanisms of opioidergic analgesia, the authors compared the action of [mu]-opioid agonist [D-Ala2, N-Me-Phe4, Gly5-ol]-enkephalin (DAMGO) on SG neurons with different intrinsic firing properties.

Methods: Whole cell patch clamp recordings from spinal cord slices of Wistar rats were used to study the sensitivity of SG neurons to DAMGO.

Results: Three groups of neurons with distinct distributions in SG were classified: tonic-, adapting-, and delayed-firing neurons. DAMGO at 1 [mu]m concentration selectively hyperpolarized all tonic-firing neurons tested, whereas none of the adapting- or delayed-firing neurons were affected. The effect of DAMGO on tonic-firing neurons was due to activation of G protein-coupled inward-rectifier K+ conductance, which could be blocked by 500 [mu]m Ba2+ and 500 [mu]m Cs+ but increased by 50 [mu]m baclofen. As a functional consequence of DAMGO action, a majority of tonic-firing neurons changed their pattern of intrinsic firing from tonic to adapting.     

B超对急性腹腔内出血的诊断价值(附52例分析)

急性腹腔内出血常见于外伤和妇科急诊病人,是急腹症最常见的并发症.患者发病急,死亡率高,因此对急性腹腔内出血的早期诊断,尤其重要.超声与X线检查及X-CT检查相比,简便易行,对急性腹腔内出血的诊断具有重要价值.     

股骨转子间骨折GAMMA钉治疗临床分析

目的：评价GAMMA钉治疗股骨转子间骨折的效果。方法：对32例股骨转子间骨折采用GAMMA钉治疗。结果：经6～18月随访，所有病例均获骨性愈合，下肢功能及关节活动良好。其中1例为粉碎性骨折内固定后出现髋内翻，按X线评分标准90％病人满意。结论：GAMMA钉治疗股骨转子间骨折效果满意。     

抗戊型肝炎病毒重组蛋白单克隆抗体的制备和初步应用

目的:制备抗-戊型肝炎病毒的单克隆抗体,并将其用于分析戊型肝炎病毒不同毒株结构蛋白的抗原表位。方法:采用来自墨西哥株(Mexicanstrain)的戊型肝炎病毒重组蛋白(p166Mex)免疫Balb/c小鼠,取其脾细胞与SP2/0骨髓瘤细胞进行融合,经酶联免疫吸附试验(ELISA)法筛选阳性克隆,并将获得的单克隆抗体与戊型肝炎病毒缅甸株(Burmastrain)和美国株(USAstrain)的重组蛋白(p166Bur、p166US)进行交叉反应测定。结果:最终获得4株能稳定分泌抗-p166Mex的杂交瘤细胞株,即D8G10、E5E12、D4A3、B7E6。其中D8G10,E5E12和B7E6细胞株的培养上清液,还能分别与p166Bur和p166US重组蛋白发生阳性反应。结论:利用已获得的抗-p166Mex单克隆抗体,初步确定3种不同的戊型肝炎病毒重组蛋白(p166Bur、p166US、p166Mex)含有一种共同的抗原表位。     

2种清洗设备洗涤医用器械的质量分析

目的通过观察全自动清洗消毒器与超声波清洗机洗涤不同类医用器械的质量,找出不同器械的最佳洗涤方法,为制订各种器械洗涤流程提供依据。方法将回收器械随机分为A洗涤法和B洗涤法。A洗涤法:将回收器械直接放入全自动清洗消毒器内按程序进行清洗、消毒和干燥。B洗涤法:将器械放入超声波机内按程序加酶浸泡、超声波清洗、冷水热水喷淋清洗消毒、上油烘干。比较2种洗涤方法的洗涤效果。结果A洗涤法洗涤后齿类器械剩余残留物为0.52‰,非齿类器械剩余残留物为0.07‰,2种器械洗涤效果差异有统计学意义(!2=28.189,P=0.000),洗涤齿类器械效果差;B洗涤法洗涤齿类器械剩余残留物为0.04‰,非齿类器械剩余残留物为0.01‰,2种器械洗涤效果差异无统计学意义(!2=1.008,P=0.313)。而2组洗涤法洗涤齿类器械效果有统计学意义(!2=44.097,P=0.000);非齿类器械洗涤后剩余残留物对比不明显,洗涤效果差异无统计学意义(!2=2.667,P=0.102)。结论采用超声波清洗机清洗齿类器械洗涤效果佳;而采用全自动清洗消毒器洗涤齿类器械洗涤效果差,但洗涤非齿类器械洗涤容量大,效果好。     

甘草酸抗病毒活性的研究进展

以国内外发表的文献为材料,简述甘草酸在抗病毒方面研究进展。对甘草酸抗肝炎病毒、疱疹属病毒、HIV病毒及SAS病毒等机制进行了综述。甘草酸抗病毒活性强,能抑制多种不相关的DNA、RNA病毒的生长,并且不影响正常细胞的活性。但由于其脂溶性和生物利用度低,及长期使用会引起一些不良反应,而限制了它的应用。总的来说,甘草酸在抗病毒方面的前景良好,有其独特优势,但其抗病毒机制复杂,很多方面有待进一步研究。