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71.
72.
白藜芦醇甙对内毒素刺激小鼠腹腔巨噬细胞产生TNFα和NAG的影响 总被引:11,自引:0,他引:11
收集小鼠腹腔巨噬细胞,调整细胞浓度为5×10 ̄5/ml,加入24孔培养板每孔1ml,内毒素刺激前后不同时间加入白藜芦醇甙培养,检测上清中肿瘤坏死因子,溶酶体酶(N-乙酰-β-D氨基葡萄糖苷酶NAG)的变化,结果说明:白藜芦醇甙可减少上清中TNF_α和NAG的量,通过此可减少内毒素刺激产生的由TNF_α和NAG介导的组织损伤。 相似文献
73.
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
74.
Only palliative treatment may be contemplated when advanced oesophageal cancers present with dysphagia. Operability depends on respiratory, hepatic and nutritional status. Resectability may be assessed on the information provided by bronchoscopy, thoracic CT scan and surgical exploration. Advanced resectable oesophageal cancers require oesophagectomy without thoracotomy and radiotherapy. We performed 93 oesophagectomies in 106 advanced oesophageal cancers with a mortality rate of less than 2%. Non resectable advanced oesophageal cancers require bypass procedures. We performed 13 in the 106 cases. Inoperable advanced oesophageal cancers require radiotherapy in the absence of a fistula, laser therapy or an endoprosthesis for dysphagia. 相似文献
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Evidence that [3H]-alpha,beta-methylene ATP may label an endothelial-derived cell line 5'-nucleotidase with high affinity. 总被引:1,自引:1,他引:0
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A. D. Michel N. M. Chau T. P. Fan E. E. Frost P. P. Humphrey 《British journal of pharmacology》1995,115(5):767-774
1. In membranes prepared from a permanent cell line of endothelial origin (WEC cells), [3H]-alpha, beta-methylene ATP ([3H]-alpha, beta-meATP) labelled high (pKd = 9.5; Bmax = 3.75 pmol mg-1 protein) and low (pKd = 7.2; Bmax = 23.3 pmol mg-1 protein) affinity binding sites. The high affinity [3H]-alpha, beta-meATP binding sites in the WEC cell membranes could be selectively labelled with a low concentration of the radioligand (1 nM). In competition studies performed at a radioligand concentration of 1 nM, 88.6% of the sites possessed high affinity (pIC50 = 8.26) for alpha, beta-meATP. 2. The high affinity [3H]-alpha, beta-meATP binding sites appeared heterogeneous since in competition studies a number of nucleotide analogues (alpha, beta-meADP, ATP, ADP, AMP, GTP, GppNHp, GMP) and adenosine identified two populations of the sites labelled by 1 nM [3H]-alpha, beta-meATP. The proportion of sites with high affinity for these compounds was found to vary between 42 and 69%. 3. Approximately 60-69% of the binding sites labelled with 1 nM [3H]-alpha, beta-meATP possessed high affinity for alpha, beta-meADP (pIC50 = 8.87), AMP (pIC50 = 7.12), GMP (pIC50 = 7.34), UTP (pIC50 = 6.12), GTP (pIC50 = 7.59), GppNHp (pIC50 = 7.35) and adenosine (pIC50 = 5.45).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
78.
ATP synthesis from PCr through creatine kinase reaction was measured in vivo in rat leg muscle using 31P NMR magnetization transfer and progressive saturation. Both techniques determined a spin-lattice relaxation time for PCr of 3 s at rest and an identical forward rate constant of 0.22-0.26 s-1. In stimulated muscles, magnetization transfer showed that flux was not changed with a steady-state PCr of 54% of initial level. During stimulation inducing a PCr decrease to 38% of initial value, flux was significantly lowered by 30%. These findings could result from an accumulation of ions and water increases or from compartmentation of ATP and PCr in different pools either in the muscle cell or in the different muscle fibers. In addition, these results could reinforce the hypothesis against a crucial role for creatine kinase shuttle in the ATP supply in skeletal muscle. 相似文献
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