毫米波辐射对白血病细胞的细胞结构、自由基和bcl-2基因表达的影响

目的 研究毫米波辐射对白血病细胞株的细胞结构、培养体系中的氧化自由基和抗氧化酶系,以及bcl-2基因表达的影响。方法 电镜显微技术研究细胞结构的变化,AnnexinV/PI双染法结合流式细胞术分析细胞株凋亡和坏死,硫代巴比妥酸（TBA）法和邻苯三酚法测定细胞株培养体系中的脂质过氧化物（LPO）和超氧化物歧化酶（SOD）的含量变化;流式细胞仪结合荧光标记抗体检测bcl-2基因表达。结果 毫米波辐射使白血病细胞株细胞结构产生显著的退行性变化,显著诱导细胞凋亡和坏死,抑制细胞活力,脂质过氧化物含量上升,SOD含量下降,bcl-2基因的表达显著下降。结论 毫米波辐射有明显的诱导白血病细胞凋亡的效应,其机制与辐射后氧化自由基水平上升、抗氧化酶系活性下降及bcl-2基因的表达下降有关。     

神经细胞粘附分子在人脑星形细胞瘤中的表达

研究神经细胞粘附分子在人脑星形细胞瘤发生发展中的作用。方法：用原位杂交和免疫组织化学方法检测４０例人脑星形细胞瘤组织中的ＮＣＡＭｍＲＮＡ及其蛋白（ＣＤ５６）的表达。结果：星形细胞瘤１,２级中ＮＣＡＭｍＲＮＡ及蛋白的表达显著高于星形细胞瘤３,４级,核酸与蛋白水平的检测结论一致。结论：ＮＣＡＭｍＲＮＡ及其蛋白的表达与星形细胞瘤的恶性程度有关,ＮＣＡＭ的高表达可与星形细胞瘤的侵袭转有关,并有可能成为星形     

天津市汉沽区媒介生物调查初报

本文报道了天津市汉沽区域媒介生物的调查结果:本地区有蚊类6种;鼠类5种;蝇类31种;蜚蠊类3种;蚤类2种;螨类1种。     

Biological response modifiers and infectious diseases: actual and potential therapeutic agents

Biological response modifiers (BRMs) are agents which can modify the immune response to cancer or invasion of the organism by infectious agents. An explosive appearance of new BRMs has resulted from the development of recombinant gene technology and the availability of monoclonal antibodies. Colony-stimulating factors first became available for the prevention of neutropenia but may also have a role in the treatment of infections. Interleukin-1 is being tested as a modular of hematopoiesis and may be useful as a helper factor for T- and B-cell function. Immunoglobulins are being used against viral and bacterial infections while interferons can prevent viral upper respiratory infections and suppress or irradicate some viral hepatitides. Other BRMs which show promise include chemical agents and traditional herbal medicines.     

Biological activity of tissue flaps in the treatment of complicated irradiation wounds

Within the last ten years, 79 patients were treated for 114 chronically contaminated, intractable irradiation wounds using various methods of the modern plastic surgery. Radical excision of the devitalised contaminated tissue has been impracticable in 25 cases due to the risk of life-threatening complications or significant functional loss. Different types of flaps such as cutaneous, fasciocutaneous, musculocutaneous, split muscle, isolated vascularised fascia and greater omentum have been used. Despite the incomplete excision, 84% of wounds healed primarily. The essential factor for good wound healing seems to be the biologic activity (BA) of the flap's deep tissue layer that directly contacts the wound bed. BA includes density of the vascular net, ability of neovascularisation, plasticity and specific immunological capacities. It seems to be possible to classify the flaps according to the BA level. Tissue defects in which the chances for radical debridement are poor need the highest BA level in the flap reconstruction.Presented to the European Congress on Wound Healing and Skin Physiology, Bochum, Germany, 1992     

Test chamber exposure of humans to 1,6-hexamethylene diisocyanate and isophorone diisocyanate

An isocyanate generation apparatus was developed and stable isocyanate atmospheres were obtained. At a concentration of 5 g 1,6-hexamethylene diisocyanate (HDI) per m³ the precision was found to be 7% (n = 5). Three volunteers were each exposed to three different concentrations of HDI (11.9, 20.5, and 22.1 g/m³) and three concentrations of isophorone diisocyanate (IPDI) (12.1, 17.7, and 50.7 g/m³), in an exposure chamber. The duration of the exposure was 2 h. Urine and blood samples were collected, and hydrolysed under alkaline conditions to the HDI and IPDI corresponding amines, 1,6-hexamethylene diamine (HDA) and isophorone diamine (IPDA), determined as their pentafluoropropionic anhydride amides (HDA-PFPA and IPDA-PFPA). The HDA-and IPDA-PFPA derivatives were analysed using liquid chromatography mass spectrometry with thermospray monitoring negative ions. When working up samples from the exposed persons without hydrolysis, no HDA or IPDA was seen. The average urinary excretion of the corresponding amine was 39% for HDI and 27% for IPDI. An association between the estimated inhaled dose and the total excreted amount was seen. The average urinary elimination half-time for HDA was 2.5 h and for IPDA, 2.8 h. The hydrolysis condition giving the highest yield of HDA and IPDA in urine was found to be hydrolysis with 3 M sodium hydroxide during 4 h. No HDA or IPDA could be found in hydrolysed plasma (< ca 0.1 g/l).     

Cancer risk assessment for health care workers occupationally exposed to cyclophosphamide

In the present study a cancer risk assessment of occupational exposure to cyclophosphamide (CP), a genotoxic carcinogenic antineoplastic agent, was carried out following two approaches based on (1) data from an animal study and (2) data on primary and secondary tumors in CP-treated patients. Data on the urinary excretion of CP in health care workers were used to estimate the uptake of CP, which ranged from 3.6 to 18 g/day. Based on data from an animal study, cancer risks were calculated for a health care worker with a body weight of 70 kg and a working period of 40 years, 200 days a year (linear extrapolation). The lifetime risks (70 years) of urinary bladder cancer in men and leukemias in men and women were found to be nearly the same and ranged from 95 to 600 per million. Based on the patient studies, cancer risks were calculated by multiplication of the 10-year cumulative incidence per gram of CP in patients by the estimated mean total uptake in health care workers over 10 years, 200 days a year. The risk of leukemias in women over 10 years ranged from 17 to 100 per million using the secondary tumor data (linear extrapolation). Comparable results were obtained for the risk of urinary bladder tumors and leukemias in men and women when primary tumor data were used. Thus, on an annual basis, cancer risks obtained from both the animal and the patient study were nearly the same and ranged from about 1.4 to 10 per million. In The Netherlands it is proposed that, for workers, a cancer risk per compound of one extra cancer case per million a year should be striven for (target risk) and that no risk higher than 100 per million a year (prohibitory risk) should be tolerated. From the animal and the patient study it appears that the target risk is exceeded but that the risk is still below the prohibitory risk.     

湖南麦饭石卫生学评价

目的　为开发利用湖南 Ｆ６、 Ｆ７ 麦饭石矿物营养的有益资源。方法　毒理学试验,观察实验动物存活、生长状况;生物活性实验,证实麦饭石中微量元素对动植物的营养作用。结果　急性、８０ 天生长试验实际无毒,并能提高小鼠的游泳耐力,延长金鱼存活时间,花卉枯萎时间后移,伤口愈合时间缩短以及吸附水中氰化物、铅、汞、砷、镉和甲醇等有毒物质。结论　麦饭石作为矿物营养资源具有广阔的的应用前景。     

The biological zero signal in laser doppler fluximetry – origins and practical implications

 This study seeks to identify the origin of the signal, known as biological zero, that is obtained using laser Doppler fluximetry when flow is arrested. It makes specific recommendations on how this signal should be measured and handled when undertaking flow studies. The experiments undertaken using flow models, animal and human tissue, organ preparations and human subjects showed that, although there may be contributions to the no-flow laser Doppler signal from vasomotion, Brownian motion from within the vascular compartment and the effects of cuff compression, the predominant contribution is from Brownian motion arising from the interstitial compartment. The biological zero signal is additive to the flow signal providing conditions within the interstitium remain constant with changes in blood flow. It is thus concluded that the biological zero signal arises from Brownian motion of the macro molecules within the interstitium. This signal should be obtained following 3–5 min of cuff occlusion with inflation applied rapidly with the smallest cuff that is compatible with flow arrest. Biological zero should be measured under each experimental condition and subtracted from the flow signal. Received: 13 August 1998 / Received after revision: 5 November 1998 / Accepted: 9 November 1998     

膨胀单体对环氧树脂的改性研究

介绍膨胀单体和膨胀聚合反应,综述膨胀单体对环氧树脂基复合材料,环氧树脂结合剂的改性研究及其进展,并提出今后的发展方向。