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排序方式: 共有851条查询结果,搜索用时 15 毫秒
1.
R Nikolov J Maslarova I Semkova 《Methods and findings in experimental and clinical pharmacology》1992,14(8):577-583
The central effects of endothelin-1 (ET-1) and their modification by the calcium entry blocker cinnarizine have been investigated using CNS and hypoxia/ischemia tests. CNS tests comprised behavior, horizontal and vertical motor activity and hot plate test. Hypoxia/ischemia tests used were hypobaric hypoxia and complete ischemia by decapitation. ET-1 was injected intracerebroventricularly (i.c.v.) in a volume of 0.01 ml at doses of 1.25, 2.5 and 5 pmol/mouse 15 min before the tests. Cinnarizine (10 mg/kg, i.p.) was administered 60 min prior to ET-1. The i.c.v. ET-1 at all the doses used decreased horizontal and vertical motor activity and produced barrel-rolling. Survival/gasping time of mice subjected to hypoxia/ischemia increased dose-dependently. ET-1 showed an antinociceptive effect. Cinnarizine attenuated the appearance of barrel-rolling, did not antagonize disturbances in motor activity and reversed the antinociceptive effect of ET-1. In hypobaric hypoxia and decapitation cinnarizine antagonized the effects of 5 pmol/mouse ET-1 and potentiated that of 1.25 pmol/mouse. The pharmacological modification of the ET-1 effects by cinnarizine strongly suggests that the CNS actions of ET-1 might be due to multiple mechanisms triggered by an increased influx of extracellular Ca2+ into the brain cells. 相似文献
2.
Inhibition by N-acetylcysteine of carcinogen-DNA adducts in the tracheal epithelium of rats exposed to cigarette smoke 总被引:1,自引:0,他引:1
Izzotti Alberto; Balansky Roumen; Scatolini Leonardo; Rovida Alessandra; De Flora Silvio 《Carcinogenesis》1995,16(3):669-672
The ability of the aminothiol N-acetylcysteine (NAC) to preventthe formation of carcinogen-DNA adducts in tracheal epithelialcells was investigated in Sprague-Dawley rats exposed whole-bodyto mainstream cigarette smoke for either 40 or 100 consecutivedays. 32P-Postlabelling analyses showed the occurrence of DNAadducts (12.49 adducts/108 nucleotides) after 40 days of exposure,with a trend to formation of characteristic diagonal radioactivezones. Total adduct levels were not further enhanced after 100days of exposure to smoke, although significant changes occurredin the amounts of individual adducts. NAC, given by gavage inthe 40 day study and in drinking water in the 100 day study,significantly inhibited the formation of smoke-related carcinogen-DNAadducts in the tracheal epithelium, to such an extent that adductlevels were not significantly higher than those detected insham-exposed control rats. Together with a variety of othermolecular, clastogenicity, metabolic, cytological and histopathologicalend-points investigated in rodents and with the preliminaryevidence arising from a study in humans, these results documentthe considerable efficacy of oral NAC in inhibiting smoke-relatedcarcinogen-DNA adducts. 相似文献
3.
Cytokine patterns in patients after major vascular surgery, hemorrhagic shock, and severe blunt trauma. Relation with subsequent adult respiratory distress syndrome and multiple organ failure. 总被引:29,自引:5,他引:24 下载免费PDF全文
R M Roumen T Hendriks J van der Ven-Jongekrijg G A Nieuwenhuijzen R W Sauerwein J W van der Meer R J Goris 《Annals of surgery》1993,218(6):769-776
OBJECTIVE: This study investigates the course of serum cytokine levels in patients with multiple trauma, patients with a ruptured abdominal aortic aneurysm (AAA), and patients undergoing elective AAA repair and the relationship of these cytokines to the development of adult respiratory distress syndrome (ARDS) and multiple organ failure (MOF). SUMMARY BACKGROUND DATA: Severe tissue trauma, hemorrhagic shock, and ischemia-reperfusion injury are pathophysiologic mechanisms that may result in an excessive uncontrolled activation of inflammatory cells and mediators. This inflammatory response is thought to play a key role in the development of (remote) cell and organ dysfunction, which is the basis of ARDS and MOF. METHODS: The study concerns 28 patients with multiple trauma, 20 patients admitted in shock because of a ruptured AAA, and 18 patients undergoing elective AAA repair. Arterial blood was serially sampled from admission (or at the start of elective operation) to day 13 in the intensive care unit, and the serum concentrations of tumor necrosis factor-alpha (TNF-alpha), interleukin (IL)-1 beta, and IL-6 were determined. RESULTS: Twenty-two patients died, 15 within 48 hours and 7 after several weeks, as a result of ARDS/MOF. At hospital admission and after 6 hours, these nonsurvivors had significantly higher plasma TNF-alpha and IL-1 beta levels than did the survivors. At the same measuring points, TNF-alpha and IL-1 beta were significantly more elevated in patients with ruptured AAA than in traumatized patients. However, IL-6 was significantly higher in the traumatized patients. In 10 patients, ARDS/MOF developed, and 41 had an uncomplicated course in this respect. Those with ARDS/MOF exhibited significantly different cytokine patterns in the early postinjury phase. TNF-alpha and IL-1 beta levels were higher mainly on the first day of admission; IL-6 concentrations were significantly elevated in patients with ARDS/MOF from the second day onward. The latter cytokine showed a good correlation with the daily MOF score during the whole 2-week observation period. CONCLUSIONS: In the early postinjury phase, higher concentrations of these cytokines are associated, not only with an increased mortality rate, but also with an increased risk for subsequent ARDS and MOF. These data therefore support the concept that these syndromes are caused by an overwhelming autodestructive inflammatory response. 相似文献
4.
The objective was to study age-related changes in sleep-wake stages in the rat by using precise polyphysiograph criteria for stage identification. Cortical and hippocampal electroencephalogram, and ocular and myographic activities were recorded in young, middle-aged, and old male Wistar rats to define 6 stages: active and quiet wake (AW, QW); light and deep slow wave sleep (SWS: S1, S2); intermediate stage of sleep (IS); and paradoxical sleep (PS). The old rats displayed a decrease in S1, S2, and IS, accompanied by an enhancement of AW. No age changes were found for QW and PS. It is suggested that the consolidation of SWS is primarily disturbed in the old rats, which may lead to a facilitation of wake. 相似文献
5.
Pauwels P Dal Cin P Roumen R van den Berghe H Sciot R 《Virchows Archiv : an international journal of pathology》1999,434(2):167-171
A case of an entirely intramuscular mixed tumour occurred in an 82-year-old man, who presented with a large mass in the region
of the right triceps muscle. A lobulated tumour was seen, with plump, round epithelioid cells embedded in a chondromyxoid
stroma. Immunohistochemical examination showed strong S100 protein and pancytokeratin positivity in most of the tumour cells.
Cytogenetic analysis revealed complex clonal chromosomal changes: 47, XY, +i (2) (q10), –15, der (17)t(15;17) (q11; p12),
+r. Differential diagnosis against extraskeletal myxoid chondrosarcoma (EMC) may be problematic, particularly in an incisional
biopsy. Chromosomal analysis can be very helpful in solving this problem, since EMC shows a specific reciprocal chromosome
translocation characterised as t (9;22) (q22–31) (q11–12).
Received: 8 July 1998 / Accepted: 22 September 1998 相似文献
6.
From the leaves and flowers of Crataegus monogyna and C. Pentagyna six new flavonoid-C- and O-glycosides respectively have been isolated and identified as 2'-O-rhamnosyl-orientin, 2'-O-rhamnosyl-isoorientin, 2'-O-rhamnosyl-isovitexin, rutin, spiraeosid, 8-methoxy-k?mpferol and 8-methoxy-k?mpferol-3-O-glucoside. The structure of O-rhamnosyl-vitexin and O-acetyl-O-rhamnosyl-vitexin isolated previously, have been elucidated unambigiously mainly by NMR- and MS-spectroscopy. 相似文献
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9.
Alison M. Dines David M. Wood Miguel Galicia Christopher M. Yates Fridtjof Heyerdahl Knut Erik Hovda Isabelle Giraudon Roumen Sedefov Paul I. Dargan Euro-DEN Research Group 《Journal of medical toxicology》2015,11(4):415-421
Cannabis is the most commonly used illicit drug in Europe, and is generally regarded
as having low acute toxicity. We present the findings of the first 6 months of data collection from
the Euro-DEN project on presentations related to cannabis use to further understand the acute
toxicity related to the use of cannabis. Data was extracted on clinical features, treatment and
outcome from the Euro-DEN minimum dataset for all cases of acute recreational drug toxicity reported
1st October 2013 to 31st March 2014 for all cannabis-related presentations. Of 2198 presentations
reported by 14 of the 16 Euro-DEN centres, 356 (16.2 %) involved cannabis either alone or together
with other drugs/alcohol. There were 36 that involved lone use of cannabis (1.6 % of all
presentations). Of the 35 non-fatal lone cannabis presentations, the most commonly reported features
were neuro-behavioural (agitation/aggression 8 (22.9 %), psychosis 7 (20.0 %), anxiety 7 (20.0 %))
and vomiting 6 (17.1 %). Most patients (25, 71.4 %) received no treatment and 30 (85.7 %) were
discharged/self-discharged from the ED. There was one fatality amongst these lone-cannabis cases: an
18-year-old male collapsed with an asystolic cardiac arrest whilst smoking cannabis and suffered
hypoxic brain injury related to prolonged cardiac arrest. THC was detected in a urine sample taken
at ED arrival; no other drugs were detected. Lone acute cannabis toxicity was typically associated
with neuro-behavioural symptoms and vomiting. Although uncommon, severe toxicity including
cardiovascular toxicity and death may be under-recognised, and it is important that Emergency
Physicians are aware of this. 相似文献
10.