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41.
Isolation of rhinoviruses and coronaviruses from 38 colds in adults 总被引:10,自引:0,他引:10
Nasal washings were collected from 27 normal adults during 38 naturally acquired colds. The washings were exhaustively tested using tissue cultures, organ cultures and electron microscopy. Washings yielding no identifiable agent were inoculated into human volunteers, and further specimens obtained from the latter were examined by the same techniques in vitro. Viruses were identified in association with 25 of the original 38 colds (65.7%). Fifteen were rhinoviruses (39.5%), seven coronaviruses (18.4%), two were para-influenza viruses, and one was influenza virus. Use of organ cultures and of volunteers significantly increased the isolation rate. No agent was cultivated from the remaining 13 specimens, although tests in volunteers showed that cold-producing agents were present in five of them (13%). Three specimens gave doubtful results in volunteers, and five others, all collected within a period of six weeks in December and January, apparently contained no infectious agent. 相似文献
42.
Arjamaa O Mäkinen T Turunen L Huttunen P Leppäluoto J Vuolteenaho O Rintamäki H 《European journal of applied physiology》2001,84(1-2):48-53
In the study reported here, we examined blood pressure and endocrine responses in cold conditions during salt load in young
healthy subjects who had previously shown increased resting blood pressure during acutely increased sodium intake. Subjects
(n=53) added 121 mmol sodium into their normal diet for 1 week. If their mean arterial pressure had increased by a minimum of
5 mmHg compared to the previous measure they were selected for subsequent experiments. The subjects (n=8) were given 121 mmol supplemental sodium · day−1 for 14 days. They were then put into a wind tunnel for 15 min (temperature −15 °C, wind speed 3.5 · ms−1). Their blood pressure increased (P < 0.05) during the cold exposure, independent of the sodium intake. Their mean (SEM) plasma noradrenaline increased from
3.58 (0.62) nmol · l−1 to 5.61 (0.79) nmol · l−1 (P < 0.05) when the subjects were given a normal diet, and from 2.45 (0.57) nmol · l−1 to 5.06 (0.56) nmol · l−1 (P < 0.05) when the subjects were given an elevated sodium diet. The starting concentrations and the endpoint concentrations
were statistically similar. The plasma levels of the N-terminal fragment of pro-atrial natriuretic peptide decreased during
the whole-body cold exposure: with the sodium load the change was from 256.6 (25.5) nmol · l−1 to 208.0 (25.3) nmol · l−1, and with the normal diet, from 205.8 (16.4) nmol · l−1 to 175.1 (16.1) nmol · l−1. The haematocrit and red blood cell count increased (P < 0.05) with normal and elevated sodium diet in cold conditions, but haemoglobin increased (P < 0.05) only with high salt in cold conditions. To conclude, acutely increased sodium intake does not change the blood pressure
response or hormonal responses to exposure to acute cold stress in healthy subjects.
Accepted: 28 September 2000 相似文献
43.
目的:研究外源笥三磷酸腺苷(adenosine triphosphate,ATP)是否能够进入低温保存大鼠肝脏细胞内。方法:采用大鼠肝脏持续低温机器灌流保存模型,利用放射自显影技术判定[α-^32P]ATP是否进入细胞内。结果:灌流液中不加[α-^32P]ATP的A组光镜照片显示大鼠肝细胞内外均未见特异性标记银粒显影,而灌流液中含37MBq[α-^32P]ATP的B组光镜照片显示大鼠肝细胞内可见多个大小不等的[α-^32P]ATP自显影银粒分布,而肝窦及肝小叶中央静脉等血管内则几乎无黑色自显银粒分布。结论:外源性ATP能够进入低温保存大鼠肝细胞内。 相似文献
44.
类风湿性关节炎是一种常见的慢性自身免疫性复杂疾病, 病因尚不明确, 治疗困难, 国内常以传统中医药手段将其辨证分型, 遵循“同病异治”的原则对其进行治疗。中医药辨证治疗类风湿性关节炎历史悠久, 效果显著, 同时中药方剂多靶点、多成分的特点使其更有效的缓解各自适应证患者的炎症症状。近年来传统中医药与西医的关联日渐加深, 西医技术与手段在中药治疗 RA 上的广泛应用, 不仅使 RA 不同证型的差异更加清晰, 中医辨病更加准确, 更在针对类风湿性关节炎适应证的中药方剂在临床、药效、生物学与治疗机制方面的研究取得了较大进展。文章基于中医“同病异治” “辨证分型”的原则, 对治疗类风湿性关节炎代表方剂与其研究进展进行综述。 相似文献
45.
目的:观察高良姜、大高良姜、红豆蔻黄酮类成分对胃溃疡寒证大鼠环核苷酸水平及交感神经-肾上腺轴的影响,探讨3味山姜属中药温热药性的物质基础。方法:采用灌服冰知母水煎液与15%冰乙酸制备大鼠胃溃疡寒证模型,以干姜姜辣素为阳性对照,采用酶联免疫吸附试验(ELISA)法测定腺苷酸环化酶(AC)、磷酸二酯酶2(PDE2)、环磷酸腺苷(cAMP)、环磷酸鸟苷(cGMP)、促肾上腺皮质激素(ACTH)、多巴胺β羟化酶(D-β-H)含量。结果:与空白组比较,胃溃疡寒证模型组大鼠胃组织AC、cAMP含量及cAMP/cGMP比值显著降低,PDE2含量显著升高(P<0.01)。与模型组比较,高良姜、大高良姜、红豆蔻高低剂量组大鼠胃组织AC含量升高;高良姜、大高良姜、红豆蔻高低剂量组大鼠胃组织PDE2含量显著降低,cAMP含量、cAMP/cGMP比值显著升高(P<0.01或P<0.05)。结论:3味山姜属中药黄酮类成分通过调节胃溃疡寒证大鼠环核苷酸水平从而促进交感神经-肾上腺轴功能活动的作用,也体现出黄酮类成分药性温热。 相似文献
46.
常温氧合血性心停搏液持续灌注心肌保护效应的实验研究 总被引:2,自引:0,他引:2
目的 采用随机对比的实验研究方法从测定心肌酶学、氧自由基代谢产物及心肌特异性蛋白几个方面来探讨冷晶体心停搏液间断灌注及常温氧合血性心停搏液连续灌注两种灌注方法的心肌保护效应。方法14只犬随机分为①对照组:冷晶体心停搏液间断灌注;②实验组:常温氧合血性心停搏液连续灌注。采集不同时点的犬冠状静脉窦血为测定标本,测定心肌特异性酶CK-MB、心肌特异性钙蛋白T(cTn-T),氧自由基代谢产物丙二醛(MDA)。结果对照组在主动脉开放后,CK-MB、MDA、cTn-T明显升高,实验组升高幅度较小。两组间比较有显著差异(P<0.01)。结论常温氧合血性心停搏液连续灌注,可以充分保证心肌在常温停跳期间的血供和氧供,避免了心肌缺血缺氧,明显地减轻了心肌缺血再灌注损伤,是一种非缺血性、比较理想的心肌保护方法。 相似文献
47.
寒热证候与鼻鼽相关性的临床研究 总被引:9,自引:0,他引:9
目的:为研究寒热证候与鼻鼽(变应性鼻炎AR)发病的相关性,进而研究鼻鼽患者的体质证候特征。方法:以鼻窒(慢性单纯性鼻炎CSR)及健康志愿者为对照,调查鼻鼽患者发病的体质证候特征,包括中医证型、血清皮质醇(F)、血清甲状腺素(T3、T4)、血浆促肾上腺皮质激素(ACTH)、鼻分泌物分泌性IgA(sIgA)及外周血嗜碱性粒细胞(BC)脱颗粒情况。结果:鼻鼽患者中医辨证多属阳气虚弱型,其血清F及鼻分泌物 相似文献
48.
49.
目的:防止生物样品中的汞在消化过程中的逸失及在测量过程中由于汞的吸附造成器皿的污染。方法:采用消化还原一体化,在恒温水浴锅与自制恒温消化器消化样品,冷原子吸收法测定发中汞。结果:标准偏差小于0.013μg/g;变异小于10.2%;样品加标回收率介于89% ̄106%。结论:本方法有效地防止了汞的逸失及对器皿的污染,精密度与准确度均符合微量分析的要求。 相似文献
50.
The relationship between pituitary corticotropin-releasing hormone (CRH) receptor changes and corticotrope responsiveness was studied during chronic cold stress. Exposure of rats to 4°C caused a gradual increase in plasma adrenocorticotropic hormone (ACTH), reaching 3-fold over the basal levels by 6 h (P< 0.005), followed by a reduction to levels only 1.3-fold over basal by 60 h. Plasma corticosterone was significantly increased after 1 h (P<0.005) and remained elevated for up to the 60 h cold exposure (P < 0.005). No significant changes in plasma thyroid-stimulating hormone, prolactin, growth hormone or vasopressin were observed at 60 h of cold exposure. CRH receptor concentration in the anterior pituitary was unchanged after 18 or 60 h cold stress, whereas in neurointermediate lobe membranes was markedly elevated. Autoradiographic analysis of pituitary CRH receptors confirmed that the increase in CRH binding was confined to the intermediate pituitary. CRH receptor levels in membranes from two brain areas, frontal cortex and amygdala, were unchanged following 60 h cold stress. The areas under the curve for the plasma ACTH and corticosterone levels following an injection of 10μg/kg ovine CRH in conscious rats, were of similar magnitude in control and 60 h cold exposed rats. Plasma ACTH responses to ether stress were significantly higher in rats exposed to cold for 60 h than in controls. In the intermediate pituitary, basal ß-endorphin/lipotropin release from isolated intermediate pituitary cells was significantly lower in cold stressed rats, and despite the increase in CRH receptors CRH-stimulated values were not higher than in controls. Following 60 h cold exposure, immunoreactive CRH content was decreased in neurointermediate pituitary extracts, while it was slightly increased in the median eminence. Exposure to ether for 5 min resulted in a significant decrease in immunoreactive CRH in the median eminence of cold stressed rats, but not in the controls. The data show a lack of correlation between changes in CRH receptor levels and responsiveness of the corticotrope in the anterior and intermediate pituitary lobes. This suggests that postreceptor events and interaction of CRH with other regulators of ACTH secretion are more likely to account for the changes in pituitary responsiveness during chronic stress. 相似文献