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61.
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
62.
急性脑梗塞患者血清肿瘤坏死因子水平变化的观察 总被引:7,自引:0,他引:7
采用双抗体夹心ELISA法对30例正常对照和36例急性脑梗塞患者血清肿瘤坏死因子(TNF)水平进行了检测。结果显示:急性脑梗塞组血清TNF水平显著高于正常对照组,血清TNF水平变化与脑梗塞容积大小密切相关,恢复期血清TNF水平显著降低。结果提示,TNF参与了脑梗塞发生后病理变化过程,检测血清TNF对判定脑梗塞容积大小有一定的临床意义。 相似文献
63.
HA Carpay P Matthijsse M Steinbuch PGH Mulde 《Cephalalgia : an international journal of headache》1997,17(5):591-595
In an open, randomized cross-over study in 124 patients, we compared the efficacy, safety and patient preference of oral and subcutaneous sum triptan in the acute treatment of migraine. Patients were treated for 3 attacks or 3 months and then crossed over. Primary clinical efficacy was defined as a reduction in headache severity on a four-point self-rating scale from severe (3) or moderate (2) to mild (1) or none (0), or mild (1) to none (0). Efficacy was evaluated 2 h after the administration of subcutaneous and 4h after the administration of oral sumatriptan. Subcutaneous sumatriptan was significantly more effective than oral sumatriptan in relieving headache (over all three attacks 78% vs 61% improvement), improving clinical disability (55% vs 41 % improvement) and relieving nausea (69% vs 53%), vomiting (72% vs 32%) and phono- or photophobia (67% vs 49%). Median time to recurrence was shorter after subcutaneous (12.5 h) than after oral sumatriptan (18 h); the number of patients experiencing a recurrence was similar Patients reported more adverse events after subcutaneous sumatriptan (1.32 per attack) than after the oral form (0.85 per attack), but all adverse events were mild to moderate in intensity and of short duration. Patient opinion was more often positive after subcutaneous sumatriptan. These results may be useful in counselling patients to choose between the available marketed formulations of sumatriptan. 相似文献
64.
G. Lallement Didier Clarençon Catherine Masqueliez Dominique Baubichon Monique Galonnier Marie-France Burckhart Michel Peoc’h Jean Claude Mestries 《Archives of toxicology》1997,72(2):84-92
Organophosphorus nerve agents are still in use today in warfare and as terrorism compounds. Classical emergency treatment
of organophosphate poisoning includes the combined administration of a cholinesterase reactivator (an oxime), a muscarinic
cholinergic receptor antagonist (atropine) and a benzodiazepine anticonvulsant (diazepam). However, recent experiments with
primates have demonstrated that such treatment, even when administered immediately after organophosphate exposure, does not
rapidly restore normal electroencephalographic (EEG) activity and fails to totally prevent neuronal brain damage. The objective
of this study was to evaluate, in a realistic setting, the therapeutic benefit of administration of GK-11 (gacyclidine), an
antiglutamatergic compound, as a complement to the available emergency therapy against organophosphate poisoning. GK-11 was
injected at a dose of 0.1 mg/kg (i.v) after a 45-min latency period to heavily intoxicated (8 LD50) primates. Just after intoxication, man-equivalent doses of one autoinjector containing atropine/pralidoxime/diazepam were
administered. The effects of GK-11 were examined on survival, EEG activity, signs of toxicity, recovery after challenge and
central nervous system histology. The present data demonstrate that treatment with GK-11 prevents the mortality observed after
early administration of classical emergency medication alone. EEG recordings and clinical observations also revealed that
GK-11 prevented soman-induced seizures and motor convulsions. EEG analysis within the classical frequency bands (beta, theta,
alpha, delta) demonstrated that central activity was totally restored to normal after GK-11 treatment, but remained profoundly
altered in animals receiving atropine/pralidoxime/diazepam alone. GK-11 also markedly accelerated clinical recovery of soman-challenged
primates. Lastly, this drug totally prevented the neuropathology observed 3 weeks after soman exposure in animals treated
with classical emergency treatment alone. GK-11 represents a promising adjuvant therapy to the currently available emergency
polymedication to ensure optimal management of organophosphate poisoning in man. This drug is presently being evaluated in
a human clinical trial for a different neuroprotective indication.
Received: 16 June 1997 / Accepted: 23 September 1997 相似文献
65.
To define the underlying mechanism of neuromuscular transmission failure induced by anticholinesterases, we simultaneously performed surface recordings of compound muscle action potentials (CMAPs) and intracellular recordings of miniature end-plate potentials (MEPPs), miniature end-plate current (MEPCs), and end-plate potential (EPPs) in rat diaphragms exposed in vitro to 1 × 10?4 to 2 × 10?2 mmol/L neostigmine methylsulfate. At low concentrations of neostigmine, repetitive stimulation of the phrenic nerve resulted in decrement followed by complete recuperation of CMAP amplitudes. This bimodal pattern was associated with maximal end-plate depolarization at the beginning of the stimulation period, increased MEPP amplitudes, and prolonged time constants of MEPC decays. Higher concentrations of neostigmine resulted in a unimodal decline of amplitudes of CMAPs and EPPS, reduced MEPP amplitudes, and a double exponential time course of MEPC decays. These results indicate that low concentrations of anticholinesterases impaired neuromuscular transmission by producing transient depolarization of the end-plate region. Higher concentrations induced desensitization and direct blockade of the end-plate receptor channel, probably in its open conformation. © 1993 John Wiley & Soncs, Inc. 相似文献
66.
硝基胍的毒性研究 总被引:2,自引:1,他引:1
目的对硝基胍的毒性进行研究,为制订卫生标准提供依据.方法包括急性毒性试验、蓄积毒性试验及亚慢性毒性试验.结果硝基胍大鼠经口LD50为8 066 mg/kg,小鼠经口LD50为10 044 mg/kg,蓄积系数大于5.3.亚慢性毒性试验中,高剂量组雄性大鼠在染毒第3周和第8周,体重有明显的负增长(P<0.05);高剂量组雄性大鼠睾丸脏器系数明显高于对照组(P<0.05);红细胞免疫功能测定结果显示,中、高剂量组大鼠红细胞受体花环率分别为10.00±2.37和7.50±2.66,明显低于对照组(P<0.05,P<0.01).其余各项指标未见明显改变.结论硝基胍属于微毒级毒物,轻度蓄积,亚慢性毒性试验对动物有一定的影响. 相似文献
67.
Sumie Yamanaka Masanori Hashimoto Masuo Tobe Kazuo Kobayashi Jun Sekizawa Masao Nishimura 《Archives of toxicology》1990,64(4):262-268
We proposed a simple method for screening assessment of acute oral and dermal toxicity using only three rats and mice of each sex at each dose level. Animals were first treated with chemicals at a dose of 2000 mg/kg and were carefully observed for compound-related morbidity and mortality. If none of the animals died, the following toxicity tests were suspended. If some of the animals died, toxicity tests at doses of 200 and 20 mg/kg were performed. The approximate LD50 values calculated by this method showed little difference between two separate laboratories and were in good agreement with LD50 values reported in the literature. Our toxicological data also showed that LD50 values were about 2–2.5 times the MNLD (maximum non lethal dose) in acute oral and dermal toxicity. This meant that a chemical could be regarded as having an LD50 of about 4000 mg/kg or higher when there was no mortality at the dose of 2000 mg/kg. A chemical with such low toxicity would not require further testing for lethal effects. Therefore, this simple method combining the fixed-dose procedure with the limit test is suitable for determination of approximate LD50 values of chemicals and for screening for necessity for classical full LD50 test using many animals.This work was supported by a grant from Ministry of Health and Welfare in Japan (No. 467 and 511) 相似文献
68.
急性肠系膜静脉血栓形成16例临床分析 总被引:1,自引:0,他引:1
目的 分析急性肠系膜静脉血栓形成 (ASMVT)的临床特征和诊断方法。方法 对北京友谊医院 1985年 10月至 2 0 0 2年 10月确诊的 16例ASMVT的临床资料进行分析 ,并结合文献 ,总结ASMVT的临床特征和诊断方法。结果 16例ASMVT患者 ,年龄 19~ 6 4岁 (平均 4 5 9岁 )。主要症状有腹痛 ( 16 / 16 )、腹胀 ( 16 / 16 )、呕吐 ( 10 / 16 )、发热 ( 8/ 16 ) ,主要体征有腹部膨隆 ( 16 / 16 )、腹膜刺激征( 16 / 16 )。误诊率 75 % ( 12 / 16 ) ,死亡率 4 4 % ( 7/ 16 )。结论 ASMVT的临床表现有一定的特征 ,早期彩色超声检查、诊断性腹腔穿刺、结合CT或肠系膜上动脉造影异常发现可对ASMVT做出正确的诊断 ,早期手术可以降低死亡率 相似文献
69.
70.