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991.
PETERSEN DEBORAH WISSINK; POWERS JOHN F.; AARDEMA MARILYN J.; LEBOEUF ROBERT A.; SMITH LAURENCE A. 《Toxicological sciences》1989,13(1):137-145
The estimated single-dose oral toxicity (50% lethality) of succinatetartrates (ST) was 23 g/kg in rats. ST produced minimalto moderate dermal irritation but no evidence of systemic toxicityin a standard acute percutaneous toxicity test in rabbits. STwas not an eye irritant in a standard rabbit low-volume eyeirritation test ST was not genotoxic in a series of six genotoxicitytests. A 14-day oral gavage study in rats at a dose range of0.051.0 g ST/kg/day produced only gastric irritation.The no-observed-effect level (NOEL) for gastric irritation was0.1 g/kg for males and 0.05 g/kg for females. A 28-day percutaneoustoxicity study in rabbits produced minimal to moderate dermalirritation and no adverse systemic effects at a high dose of450 mg ST/kg/day. Single-dose absorption, distribution, andelimination (ADE) studies in male rats showed that 1015%of an oral dose and 13% of a dermal dose were absorbed.Approximately 98% of the orally administered ST was eliminatedas 14C in urine, feces, or expired CO2 after 72 hr. Approximately80% of the dermally absorbed 14C dose was eliminated in urine,feces, or expired CO2 after 72 hr. In conclusion, no adverseeffects were noted in acute toxicity, genotoxicity, or subchronictoxicity studies conducted with ST. 相似文献
992.
993.
目的探讨装潢居室空气中挥发性化合物的遗传毒性.方法采用小鼠骨髓嗜多染性红细胞微核试验和小鼠精子畸形试验检测居室装潢后空气中挥发性化合物的遗传毒性.结果该化合物对小鼠呼吸系统有明显的刺激作用,与阴性对照组比较,高、中、低剂量组的微核率、精子畸形率均有显著差异性.结论居室装潢后室内空气中挥发性化合物具有遗传毒性作用. 相似文献
994.
The monoclonal anti-idiotopic antibodies LCI and 9G4 bind two non-overlapping sets of VH 4 encoded antibodies. 9G4 exclusively binds VH 4–21 encoded antibodies, while LCI binds antibodies derived from VH 4 family gene segments V71-2, V71-4, VH 4-18, VH 72-I and V2-1. The VH 4–21 gene segment is utilized by most cold agglutinin (CA) antibodies with I/i specificity, while antibodies encoded by other VH 4 gene segments are associated not with CA disease, but primarily with rheumatoid-factor (RF) activity.
We previously determined that the idiotope to which 9G4 binds in VH 4-21-derived antibodies is located in framework region l (FR1). In the present study, by using mutational analysis involving individual framework- and complementarity-determining region exchanges between VH 4-2I- and V71-2-encoded antibodies, we have found that the idiotope to which LCI binds in V71-2-derived antibodies also maps to FR1. The LC1 idiotope is heavy (H)-chain associated, but requires pairing with a light (L) chain for LCI binding. Recombinant antibodies composed of a variety of kappa (k) and lambda L chains paired with either a V71-2 or VH 4–21 chain were produced in the baculovirus expression system. LCI bound all of the k-containing antibodies but did not bind the V71-2-encoded H chain alone nor to the two A-containing antibodies. This experiment demonstrates that not all light chains exert equivalent influence on the conformation of the H-chain idiotope. These results indicate that the FR1 of VH 4-encoded antibodies is immunogenic and suggest a physiological role of FR l during an immune response. 相似文献
We previously determined that the idiotope to which 9G4 binds in V
995.
全脑全脊髓照射仰卧位CT模拟定位技术 总被引:1,自引:1,他引:1
目的:探讨全脑全脊髓照射仰卧位CT模拟定位技术。方法:7名患者分别躺在真空负压袋固定器上,进行CT模拟定位,打印正侧位数字重建射线彩像(DRR)图,放射治疗前拍摄正侧位定位验证片,测量解剖参考点和射野边界之间的距离。结果:患者左右方向及背腹方向误差在2mm以内。人体上下方向误差在4mm以内;放疗后,患者受照射的皮肤部位均出现色素沉着。结论:仰卧位全脑全脊髓照射CT模拟定位技术可用于俯卧位不合作的患者。 相似文献
996.
改变在体兔左心室后负荷对其电生理参数的影响 总被引:3,自引:1,他引:3
目的:探讨改变在体兔左心室后负荷对室性心律失常发生情况及左心室电生理参数的影响。方法:改变左心室后负荷,观察室性心律失常发生情况,并测定左心室舒张阈值(VDT),相对不应期(RRP),有效不应期(ERP)及其不应期离散和心室纤颤阈(VFT)。结果:逐级增加左心室后负荷(AB级)可使左室空间RRP,ERP离散增加(B级,P<005),VFT降低(B级,P<001);各实验动物均出现室性心律失常(B级);而逐级减小左室后负荷(CD级),心室电生理参数无变化(P>005),各实验动物亦无室性心律失常发生。结论:增加左心室后负荷诱发室性心律失常,与左室空间不应期离散增加有关。 相似文献
997.
双歧杆菌对早产儿食道pH值的影响及临床意义 总被引:2,自引:0,他引:2
目的为探讨双歧杆菌对早产儿食道pH值的影响,及其对早产儿易发生的消化道疾病的防治意义。方法我们采用便携式24hpH值自动记录仪,对61例早产儿进行了食道pH值的动态监测。结果口服双歧杆菌活菌制剂组的30例早产儿,食道pH值明显高于未服药的对照组,t=2.4093,P<0.05。总pH值<4的时间占总观察时间的百分比显著小于对照组。并且治疗组发生消化道疾患的人数也较对照组少。结论早产儿口服双歧杆菌活菌制剂可以减少胃食道反流等消化道疾病的发生。 相似文献
998.
小鼠甲胎蛋白与结核杆菌热休克蛋白70基因融合载体的构建及体外表达 总被引:1,自引:0,他引:1
目的 构建小鼠甲胎蛋白(α-Fetoprotein,AFP)与结核杆菌热休克蛋白70(Mycobacterium tuberculosis heat shock protein 70,Mt.HSP70)基因融合载体.并研究其在真核细胞中的表达情况。方法 以pcDNA3.1为基本单位构建AFP及HSP70的融合表达载体,融合基因以G-S-G-G-S连接子连接;用脂质体将系列载体导入COS-7细胞.48h后以免疫化学方法检测其表达。结果 构建的AFP和HSP70的单独及融合表达载体导入COS-7细胞48h后经RT-PCR检测可扩增出相应片段,细胞免疫化学染色为阳性。结论 AFP和HSP70的单独及融合表达载体构建成功,并能在真核细胞中表达。 相似文献
999.
1000.
Intending to clarify the true Incidence of Invasive lobular carcinoma of the breast In Japanese women as well as the frequency of unilateral multlcentriclty, 362 cases of clinically defined monocentrlc breast cancer without pre-operative biopsy (previously fine needle aspiration or needle biopsy were routinely carried out for every case) were examined by whole mammary gland serial sectioning. On the basis of pathology and the World Health Organization classification of breast tumors, each case was assigned to one of two main histologlc types: Invasive lobular carcinoma (ILC) or Invasive ductal carcinoma (IDC). Invasive lobular carcinoma was further separated into classic and variant types by employing previously published criteria. Twenty-one cases of ILC (5.8%) were diagnosed, which Is more than In most previous Japanese studies. Unilateral multicentric breast carcinoma was detected In 9.5% of ILC and 16.1% of IDC (the difference was found not significant). Microscopically, ILC tumors were found to be, on average, larger than IDC. Patients with classic type ILC tended to be younger than those with variant type or IDC. Estrogen receptor expression was found more frequently In variant type ILC than in classic type. These results suggest that the incidence of invasive lobular carcinoma of the breast In Japanese women is low and that unilateral multicentricity Is not significantly higher in ILC than in IDC. 相似文献