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991.
A I Eidelman 《The Journal of pediatrics》1989,114(2):340-341
992.
The incidence and mortality of acute epiglottitis were retrospectively analysed covering a 12-year period, 1975-1987. The diagnosis was made by the laryngoscopic findings in 95% of patients. Based on 902 hospitalized patients, a mean annual incidence of 4.9 cases per 100,000 children and adults was found. Although adult patients predominated (60%), the incidence was far higher in children, 13.8 per 100,000 compared with 3.9 per 100,000 in adults. Two peaks in incidence were identified, one for the youngest children, and the second for young adults (15-29 years). Over the years the incidence varied little in adults, but decreased significantly in children over the last 6 years studied. The data presented indicate acute epiglottitis to be a more frequent disorder than previously believed but with less risk of a fatal outcome. The mortality rate was below 1% in children and adults and the annual incidence of death from acute epiglottitis was estimated at 0.5 cases per million. The primary admission of these patients to ENT units seems to be the single factor having the most powerful impact on mortality. 相似文献
993.
B J Braakhuis D A Laarman J J Nauta M van Walsum G A van Dongen G B Snow 《Archives of otolaryngology--head & neck surgery》1989,115(9):1076-1078
Tumor material from 91 patients with squamous cell carcinoma of the head and neck was transplanted subcutaneously in athymic nude mice. In the first (man to mouse) passage, the calculated mean probability of tumor take in a single mouse was 11%. The probability of growth in the first passage was significantly better for moderately and poorly differentiated tumors than for well-differentiated tumors. Also, the implantation of lymph node material resulted in a significantly better tumor take rate than material taken from a primary tumor. Transplantability was not dependent on the following characteristics: localization, T or N stage of the tumor, or the sex of the patients. Once growth was established, all variables studied had no influence on the probability of growth in the subsequent mouse passages. A relationship between tumor growth in nude mice and patient prognosis could not be found. When transplanting head and neck squamous cell carcinoma in nude mice, it has to be recognized that some tumor characteristics will influence the success of tumor growth. 相似文献
994.
To determine whether well-appearing children found incidentally to be neutropenic are at risk for an infectious complication, 44 consecutive months of hematology laboratory records were reviewed. One hundred nineteen patients had medical record documentation regarding clinical course, serial white blood cell counts, and the absence of serious infections, chronic illnesses, or a family history known to be associated with neutropenia. The median duration of documented neutropenia was 13 days (range, 1 to 491 days). Infectious complications occurred in 4 of the 36 patients who had neutropenia for more than 30 days (2 with stomatitis, 1 with cellulitis, and 1 with pneumonia) but in none with shorter durations of neutropenia. There were no significant associations between the development of an infectious complication and either the initial absolute neutrophil count or the lowest documented absolute neutrophil count, nor was there a correlation between the initial absolute neutrophil count and the duration of neutropenia. These data indicate that infectious complications occur in otherwise well children with unexplained neutropenia that persists, but these infections are infrequent and usually are superficial. 相似文献
995.
This paper suggests that like ethanol, methanol also produces certain changes in the steady state level of monoamines in hypothalamus and striatum of albino rats. Though, the toxic manifestations of methanol are attributed to the metabolic end product of methanol viz. formic acid by several workers, we report here that the methanol-induced brain monoamine changes, at least, could be attributed to the direct action of methanol rather than to its metabolic end products like formaldehyde or formate. Studies in the steady state level of rat brain monoamines have shown that after methanol administration (3 g/kg), there is severe depletion of dopamine level in striatum but a significant increase in the level of dopamine, serotonin and 5-hydroxy indole acetic acid in hypothalamus. At the same time, norepinephrine and epinephrine levels are reduced in hypothalamus as well as in striatum. These effects do not seem to be induced by metabolic acidosis. The changes in monoamine levels are very well correlated with the blood and brain level of methanol as evidenced by maintaining a higher methanol level either by simultaneous administration of ethanol or by blocking methanol metabolism by pretreatment with 4-methyl pyrazole and 3-amino-1,2,4-triazole. It is thus postulated that monoamine changes induced by methanol appear to be the direct effect of methanol per se on the monoaminergic neuronal membranes. 相似文献
996.
Dietary factors in the risk of bladder cancer 总被引:2,自引:0,他引:2
C La Vecchia E Negri A Decarli B D'Avanzo C Liberati S Franceschi 《Nutrition and cancer》1989,12(1):93-101
The relationship between selected dietary factors and the risk of bladder cancer was investigated in a case-control study conducted in northern Italy. The study included 163 cases and 181 controls who were hospitalized for acute, nonneoplastic or urinary tract diseases. The frequency of consumption of green vegetables and carrots was lower in the cases; thus, the estimated relative risks for the upper vs. the lower tertiles were 0.6 for green vegetables and 0.5 for carrots. Significant inverse trends in risk emerged with estimated carotenoid (as well as retinoid) intake. The apparent protection conveyed by vitamin A was stronger in current smokers. The risk of bladder cancer was not related to scores of fat and measures of alcohol consumption; the risk was elevated in coffee drinkers (although there was no tendency to rise with higher consumption), but it was reduced in tea drinkers. These findings were not explainable in terms of selection, information, or confounding bias. Thus, although available information is too uncertain for any precise definition of specific (micro)nutrients related to bladder cancer risk, the confirmation that several aspects of a less-affluent diet adversely affect the risk is still of interest in terms of a better understanding of bladder carcinogenesis. 相似文献
997.
Five 3'-fluorinated ribonucleosides were prepared and evaluated for their inhibitory properties against different viruses. The synthesis of these compounds was achieved by treatment of 2',5'-di-O-tritylated nucleoside analogues possessing a xylo-configuration with diethylaminosulfur trifluoride, followed by deprotection. 3'-Fluoro-3'-deoxyadenosine was active against a broad range of viruses, encompassing both DNA viruses [pox (vaccinia)], single-stranded (+) RNA viruses [picorna (polio, Coxsackie B), toga (sindbis, Semliki Forest)] and double-stranded RNA viruses (reo). In its antiviral activity spectrum 3'-fluoro-3'-deoxyadenosine clearly differed from those adenosine analogues that are known as inhibitors of S-adenosylhomocysteine hydrolase. 3'-Fluoro-3'-deoxyadenosine also proved effective in vivo, in inhibiting tail lesion formation in mice inoculated intravenously with vaccinia virus. 相似文献
998.
G J Blauw P van Brummelen P C Chang P Vermeij P A van Zwieten 《Journal of cardiovascular pharmacology》1989,14(1):14-21
The influence of age on the regional arterial and venous effects of serotonin (5-HT) was investigated in 13 young (aged 22-31 years) and seven older (aged 50-69 years) healthy volunteers. Single-dose infusions of 5-HT (1, 10, and 80 ng/kg/min) and of the 5-HT2 receptor antagonist ritanserin (50, 150, and 500 ng/kg/min) were administered into the brachial artery. Subsequently, the relative arterial and venous effects of the highest dose of 5-HT were investigated. Forearm blood flow (FBF) and maximum venous outflow (MVO) were measured by venous occlusion plethysmography. Heart rate (HR) and intraarterial (i.a.) blood pressure were recorded semicontinuously. In both age groups, 5-HT induced an initial transient arterial dilation, followed by a persistent increase in FBF for the doses of 1 and 10 ng/kg/min and a relative small decrease in FBF for the highest dose. In both age groups, the highest dose of 5-HT induced a similar large reduction in MVO (p less than 0.05 for both). The reduction in MVO was attenuated by ritanserin (500 ng/kg/min, p less than 0.05 for both groups). In the younger subjects, this dose of ritanserin also unmasked an arterial dilator effect of the highest dose of 5-HT (p less than 0.05). The single infusions of ritanserin did not influence FBF significantly in either study group. No significant differences were observed between the age groups. These results show that in the forearm of healthy subjects arterial and venous vascular responses to 5-HT were not age-related. In the arterial vascular bed, 5-HT acted predominantly as a vasodilator; at high doses, mainly venous vasoconstriction was observed.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
999.
Venom from the scorpion Pandinus imperator potently and selectively blocks voltage-gated K+ channels in bullfrog neurones (Pappone, P. A. and Cahalan, M. D. 1987, J. Neurosci. 7, 3300-3305). Its effects on neuromuscular transmission have now been assessed. Twitch tension studies on chick biventer cervicis preparations showed that the venom (1 microgram/ml and above) significantly augmented responses to nerve but not muscle stimulation; there was little change in postjunctional sensitivity to cholinoceptor agonists or K+-induced depolarization. Electrophysiological studies on mouse triangularis sterni preparations revealed that the venom had no effect on spontaneous transmitter release, but increased evoked transmitter release. Extracellular recordings of nerve terminal action potentials showed that the venom selectively reduced the component of the waveform associated with K+ currents. These results confirm that this venom can selectively block neuronal K+ currents, and they show that this can facilitate the release of acetylcholine at the neuromuscular junction. 相似文献
1000.
A topical formulation of ketoprofen, a widely used nonsteroidal antiinflammatory drug, has recently been developed. Ten healthy young subjects (mean age 23.5 +/- 2.5 years) received daily 15 g of 2.5% ketoprofen gel, corresponding to 375 mg on the skin of the back over an area of 750 cm2. Plasma samples were collected after the first dose and after 10 days of chronic treatment. Urine was also collected. Ketoprofen was assayed by HPLC. The peak plasma concentration was 144 +/- 91 ng/ml after the first administration with apparent absorption and elimination half-lives of 3.2 +/- 2.4 h and 27.7 +/- 18.0 h, respectively. The total quantities of ketoprofen eliminated in the urine represented about 2.6% of the first dose applied. At the end of the study, the apparent half-life of unchanged ketoprofen was 17.1 +/- 9.1 h, and there was no accumulation. In this study, no sign of local intolerance was seen. 相似文献