运动训练对雄性大鼠垂体─性腺轴功能的影响

本研究通过使用自己制造的大鼠流动水游泳池，对雄性大鼠进行了６周递增负荷的游泳训练，以此来探讨运动训练对大鼠垂体－性腺轴功能的影响，结果显示：与安静对照大鼠相比，训练大鼠的一般状态较差，血清睾酮水平显著降低（Ｐ＜０．０５），血清睾酮／皮质酮比值平均降低了３０％以上；而血清ＬＨ和ＦＳＨ水平未见明显变化。通过对大鼠睾丸组织ＬＨ／ＣＧ受体的测定，显示运动训练虽未引起其最大结合量的改变，却能使其解离常数显著升高（Ｐ＜０．０５）。提示此种训练可能通过降低睾丸ＬＨ／ＣＧ受体对垂体分泌ＬＨ的亲和力，从而影响睾酮的合成。     

吡那地尔对体外培养大鼠大脑皮层神经细胞缺氧缺糖损伤的保护作用

目的 :探讨ATP敏感性K+ 通道 (KATP)开放剂吡那地尔 (pinacidil,Pin)对缺氧缺糖再复氧损伤大鼠大脑皮层神经细胞的保护作用。方法 :体外培养大鼠大脑皮层神经细胞 ,细胞培养至 10d ,建立神经细胞缺氧缺糖损伤模型 ,观察Pin及KATP阻断剂格列苯脲对缺氧缺糖不同时间 ,再复氧 2 4h后细胞死亡率、丙二醛 (MDA)含量、超氧化物歧化酶 (SOD)活力的影响。结果 :缺氧缺糖、再复氧后大鼠的神经细胞死亡率均显著升高、MDA生成增多、SOD的活力下降 ,Pin干预后 ,细胞死亡率下降、MDA生成减少、SOD的活力升高 ;格列苯脲能拮抗Pin这种保护作用。结论 :Pin对缺氧缺糖损伤神经细胞具有保护作用 ,并与拮抗氧自由基有关     

重庆某高校桶装饮用水及饮水机微生物污染检测情况分析

目的 了解桶装饮用水及饮水机微生物污染状况，探讨其原因并提出处理措施。方法检测了25桶桶装饮用水及43台饮水机用水的细菌总数和霉菌。结果 桶装饮用水及饮水机用水的细菌总数和霉菌都有一定的超标。结论 造成桶装饮用水及饮水机用水水质微生物超标的原因包括生产厂家因素、用户因素、卫生部门监管力度、市场规范等等方面。     

中国饮用水源水中藻类卫生标准的研究

为制定饮用水源中藻类限值 ,结合国内外文献调查研究毒理学试验和现场生态学调查资料 ,根据世界卫生组织 (WHO)和卫生部推荐的饮用水中微囊藻毒素MC -LR的限值、藻类生物量和MC -LR浓度关系以及毒理学实验所得到的藻类的无作用浓度而制定饮用水源中藻类限值。结果显示 ,推荐饮用水源中藻类三级限值分别为 :安全限值 :1.0× 10 4个 升 ;警戒限值 :2 .1× 10 5个 升 ;危险限值 :1.2× 10 6 个 升。提示饮用水源中藻类限值在日常工作中有显著意义和可行性     

Type II sodium channels in spinal cord astrocytes in situ: Immunocytochemical observations

The expression of sodium channel α-subunit isoforms in astrocytes in adult rat spinal cord and optic nerve was examined utilizing immunocytochemical methods with antibodies generated against conserved and subtype-specific sequences of the sodium channel. In adult rat spinal cord, astrocytes within the dorsal and ventral funiculi were immunolabelled with antibody SP20, which recognizes a conserved sequence within sodium channel types I, II, and III. In addition, astrocytes within these spinal cord white matter tracts were immunostained with antibody SP11-II, which recognizes sodium channel type II. Antibodies SP11-I and SP32-III, which are directed against subtype-specific sequences in sodium channel types I and III, respectively, did not label astrocytes in the dorsal and ventral funiculi of the spinal cord. In optic nerves, astrocytes were immunostained with antibody SP20. However, no detectable labelling of cells within the optic nerve was observed with antibodies SP11-I, SP11-II, and SP32-III. These observations demonstrate that sodium channel II is expressed by astrocytes in spinal cord white matter. Moreover, these data suggest that regional factors regulate the level of sodium channel isoform expression in astrocytes.     

车载苯胺泄漏事故造成水井污染的监测分析

2003年12月30日一辆装载7.28t苯胺的槽车从宁波开往温州的路上在甬台温高速公路温岭市境内翻车,造成5.3t左右的苯胺泄漏在高速公路旁的环境中,除少量的液体被清除外,绝大部分渗入地下,造成了水井污染.从12月31日开始我们对周围的水井开展了监测,现将监测结果分析如下:     

Skin reactions to irritants assessed by non-invasive bioengineering methods

Pathophysiological components of irritant contact dermatitis caused by 3 chemically-different irritants were investigated. 20 healthy volunteers were patch tested with sodium lauryl sulphate, nonanoic acid and hydrochloric acid on the flexor side of the upper arm. The skin response was evaluated after 24, 48 and 96 h by visual scoring and measured by the following bioengineering methods: transepidermal water loss measurement, electrical conductance for measurement of skin hydration, laser Doppler flowmetry for measurement of cutaneous blood flow and 20 MHz ultrasound A-scan for measurement of skin thickness. In spite of homogeneous inflammatory responses, significant differences in the severity of the injury to the skin barrier function caused by the different irritants were found. Also significant differences between irritants were found in the time course of development of maximum irritant reactions. Bioengineering methods indicating inflammatory responses (measurement of blood flow and skin thickness) were helpful in quantifying the irritant response in general, while bioengineering methods indicating epidermal damage (measurement of TEWL and electrical conductance) were helpful in classifying the individual irritants.     

微电流与低浓度氯对水中脊髓灰质炎I型病毒的协同灭活效应

目的　观察微电流 (low amperage direct current,LDC)与游离氯 (free chlorine,FC)对水中脊髓灰质炎 I型病毒 (PV1 )的协同灭活效果 .方法　用微电流 0 .4～ 1 .2 m A·cm-2 协同氯 0 .2～ 0 .3 mg· L-1 处理污染 PV1水样 ,比较作用前后灭活率 K值评价灭活效果 ,用 Berenbaum方法判断微电流与氯灭活病毒有无协同效应 ,用蚀斑形成试验 (PFUA)和病毒细胞酶联免疫试验 (VELCIA)检测感染性和抗原性变化 .结果　实验观察到微电流达到 0 .4 m A· cm-2 对水中PV1有弱灭活作用 ,电流密度达到 1 .2 m A· cm-2 与 0 .2mg· L-1氯有协同灭活效应 ,微电流 1 .2 m A· cm-2与氯 0 .3mg· L-1协同消毒 30 min,水中病毒减少 4.0 8个对数级 ,而单独用氯仅减少 1 .93个对数级 ;协同作用后病毒感染性灭活增强 ,而抗原性灭活不明显 .结论　微电流协同氯可提高低浓度氯灭活水中病毒的效果     

几种评价保湿产品无创性测试方法的相关性评价

目的:对测量皮肤角质层含水量和屏障功能的几种无创性皮肤测试方法进行相关性评价。方法:采用SKICON-200测定皮肤电导法、皮肤保水功能测定、TEWL测定、受试者主观评价的方法,比较某种保湿霜/精华素使用前、后皮肤角质层含水量和屏障功能的变化,并分析这些方法之间的相关性。结果:保湿霜的效果优于精华素,SKICON-200测定皮肤电导法、皮肤保水功能测定以及部分受试者临床症状和主观评价指标(如红斑、脱屑情况,皮肤滋润度的改善、皮肤细纹数量变化和皮肤弹性改善)有很好的平行关系。TEWL结果在本试验中变化不大,与上述指标没有平行关系。结论:SKICON-200测定皮肤电导法、皮肤保水功能测定适合用于保湿化妆品的功效评价。TEWL测定对于屏障功能受损的皮肤可能更敏感,对于健康皮肤使用前、后比较可作为参考指标。