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When living organisms become sick as a result of a bacterial infection, a suite of brain-mediated responses occur, including fever, anorexia and sleepiness. Systemic administration of lipopolysaccharide (LPS), a common constituent of bacterial cell walls, increases body temperature and non-rapid eye movement (NREM) sleep in animals and induces the production of pro-inflammatory prostaglandins (PGs). PGE2 is the principal mediator of fever, and both PGE2 and PGD2 regulate sleep–wake behavior. The extent to which PGE2 and PGD2 are involved in the effect of LPS on NREM sleep remains to be clarified. Therefore, we examined LPS-induced changes in body temperature and NREM sleep in mice with nervous system-specific knockouts (KO) for the PGE2 receptors type EP3 or EP4, in mice with total body KO of microsomal PGE synthase-1 or the PGD2 receptor type DP, and in mice treated with the cyclooxygenase (COX) inhibitor meloxicam. We observed that LPS-induced NREM sleep was slightly attenuated in mice lacking EP4 receptors in the nervous system, but was not affected in any of the other KO mice or in mice pretreated with the COX inhibitor. These results suggest that the effect of LPS on NREM sleep is partially dependent on PGs and is likely mediated mainly by other pro-inflammatory substances. In addition, our data show that the main effect of LPS on body temperature is hypothermia in the absence of nervous system EP3 receptors or in the presence of a COX inhibitor. 相似文献
3.
Anne T. Berg Shlomo Shinnar‡§ Eugene D. Shapiro Morton E. Salomon‡ Ellen F. Crain‡ W. Allen Hauser§ 《Epilepsia》1995,36(4):334-341
Summary We conducted a matched casecontrol study to identify risk factors for first febrile seizures, with special emphasis on characteristics of the acute illness episode. Cases were identified through hospital emergency departments; controls were identified through outpatient clinics and emergency departments. Sixtynine children with first febrile seizures and no history of previous unprovoked seizures were matched for age (±6 months), site of routine pediatric care, and date of visit (±weeks) with 1 or 2 febrile controls who had no history of previous febrile or unprovoked seizures. Medical records for the index visit were reviewed, and parents were interviewed by telephone. Illness characteristics examined included height of temperature, type of underlying illness, contact with a physician during the illness but before the index visit, and use of acetaminophen or decongestants. Family history of febrile and of unprovoked seizures, sociodemographic characteristics, daycare use, and selected preand perinatal variables were also studied. On multivariable analysis, significant independent risk factors were height of temperature, history of febrile seizures in a firstor in a higher degree relative. Gastroenteritis as the underlying illness had a significant inverse (i.e., protective) association with febrile seizures. Maternal smoking during pregnancy was a marginally significant predictor of febrile seizures. 相似文献
4.
目的:考核HFRS地鼠肾细胞Ⅱ型灭活疫苗的安全性、免疫法及其流行病学效果。方法:采用间接免疫荧光抗体试验(IFA)、微量细胞变性中和试验(MCPENT),检测接种者血中荧光抗体及中和抗体水平;调查接种组与对照组发病情况。结果:以怀宁、广德两县18个村为疫苗观察现场,接种组7499人,对照组7261人,中强反应率为224%(5/223)。3针全程免疫后中和抗体阳转率为63.33%(19/30),荧光抗体阳转率为38.58%(27/70);接种后1年内接种组无发病,对照组发病3例。结论:该疫苗的安全性较好;有一定水平的免疫应答,但防病效果应进一步观察确证。 相似文献
5.
18F-FDG PET显像在发热待查患者中筛查淋巴瘤的价值 总被引:6,自引:0,他引:6
目的 探讨18F 脱氧葡萄糖 (FDG)PET显像在长期发热患者中筛查淋巴瘤的价值。方法 对 5 9例长期发热患者 (发热持续时间至少 3周 ,测 3次体温超过 38 3℃ )的18F FDGPET显像资料进行回顾性分析 ,将18F FDGPET显像诊断结果与病理检查及随访结果进行比较。结果 5 9例长期发热患者中有 8例PET显像示恶性淋巴瘤可能 ,最后均经病理检查确诊为淋巴瘤 ,其中 2例为霍奇金淋巴瘤 ,6例为非霍奇金淋巴瘤。结论 PET显像示长期发热的淋巴瘤患者其病变淋巴结可在正常范围内 (<1 0cm或在体内较深部位 )。对长期发热患者 ,18F FDGPET显像可初步筛查淋巴瘤及排除其他肿瘤 ,可为穿刺活组织检查提供定位信息。 相似文献
6.
在杏仁内侧核微量注射精氨酸加压素(AVP)和精氨酸加压素单克隆抗体(AVPMc-Ab),观察其对兔内毒素(ET)性发热效应的影响。结果表明,杏仁内侧核微量注射AVP能明显抑制兔ET性发热效应,注射AVPMcAb则能明显提高兔ET性发热效应;而将AVP和AVPMCAb注射到杏仁外侧核则对兔ET性发热效应无明显影响。提示:杏仁内侧核也是AVP抗热作用的一个重要作用部位。 相似文献
7.
目的:探讨常见呼吸道发热疾病的临床特点及与传染性非典型肺炎(严重急性呼吸综合症,SAGS)的鉴别。方法:发热门诊诊治的以发热体温高于38℃伴呼吸道症状患者702例,对病因、临床表现、实验室检查、胸部X线、治疗及转归进行比较。结果:常见呼吸道发热患者中,急性上呼吸道感染596例占总数的85%,577病例白细胞计数不高占82%,淋巴细胞计数不降低,X线检查正常或仅有支气管炎表现。有基础肺部或全身疾病患者,虽然有发热,但往往以肺部或全身原发疾病相应症状为重要或首发表现,可有气急,体温以中度发热为主,78%病例有白细胞计数及中性比例升高。胸片除肺炎改变外,多有肺部基础疾病的表现,抗生素治疗有效;而单纯性肺炎胸部X线多表现为节段性或局灶性肺炎。这部分病例也以发热为主要或首发症状,一般表现为咳嗽、咳痰,气急少见,易与SARS混淆。结论:临床呼吸道发热疾病以急性上呼吸道感染最多见,容易忽略,要注意筛查。单纯性肺炎与SARS的鉴别,应结合流行病史、治疗反应及实验室检查结果进行。 相似文献
8.
Tetsuji Fujita Katsuhiko Yanaga 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2007,392(2):127-130
BACKGROUND: Although there is increasing evidence suggesting that the vagus nerve functions as a connector between the nervous and immune systems in animals, little is known about the role of the vagus nerve in postoperative acute phase response in humans. MATERIALS AND METHODS: The extent of fever and acute phase protein response and the production of inflammatory cytokine during the early postoperative period were compared among the patients who had undergone total gastrectomy including truncal vagotomy (n = 13), those having distal gastrectomy with division of vagal branches (n = 14), and the patients with vagal nerve preserving gastrectomy (n = 12). RESULTS: There was no significant difference in serum levels of C-reactive protein, alpha-1-antirypsin, and interleukin-6 among the three groups. Also, postoperative maximum body temperature was similar. CONCLUSIONS: Vagotomy did not influence acute phase response after gastric cancer surgery. A multipathway mechanism for acute phase response including the induction of fever is suggested. 相似文献
9.
本文采用荧光素钠正常鼠脑悬液做模拟示踪物质,对肾综合征出血热病毒气溶胶在空气中的物理稳定性进行了测定,并与其生物稳定性做了比较。结果表明:病毒气溶胶的粒子大小在1um左右,它随气溶胶的胶龄增长而减少,且其分散度变窄。初始气溶胶的物理回收率及其各胶龄的物理存留率均明显地高于它的生物回收率和生物存活率。本文还就肾综合征出血热病毒气溶胶的物理稳定性和生物稳定性,对本病空气传播的影响进行了讨论。 相似文献
10.
呼和浩特市历史上未曾发现流行性出血热自然疫源地,也未见到流行性出血热疫情报告。1995年3月,本市中文齐镇发生1例临床表现典型并经血清学证实的流行性出血热病例。病家及其周围居民区家鼠密度为3.61%,以褐家鼠为优势种。送检捕获鼠鼠肺51份,阳性率21.57%。病家周围健康人群流行性出血热隐性感染调查,阳性率2.71%(1/37)。流行病学调查表明,病人病前1周-2个月内无外出史,故病人系本地感染。动物流行病学调查证实,呼和浩特农区存在流行性出血热自然疫源地。 相似文献