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61.
Clinical investigations of laser photobioactivation, or biostimulation, might be differently designed and more fruitful if knowledge of basic biochemical mechanisms were better understood. In this investigation, biochemical events identified as responses to 904 nm irradiation included increased ascorbic acid uptake by fibroblasts. These cells also showed increased hydroxyproline formation, and this was increased several-fold by the addition of proline to the medium. Maximum biochemical responses were observed at a pulse frequency of 67 Hz and a pulse width of 150 nsec with an energy density of approximately 7 mJ/cm2 per exposure. Elements in the mitochondrial cytochrome system are proposed as the radiation absorbing chromophore(s). Hypothetically, the energy generated is linked to ascorbic acid uptake, which in turn stimulates collagen synthesis. 相似文献
62.
M. Ahmad Agil S. Risco M. Mir M. C. Navarro M. A. Ocete J. Jimnez 《Phytotherapy research : PTR》1995,9(2):135-138
The dried (elaterium) or fresh juice from Ecballium elaterium fruit is used in the treatment of various inflammatory conditions in popular medicine. In this study the elaterium is examined for its analgesic and antipyretic effects in several animal models. The elaterium exhibits both analgesic and antipyretic activities. 相似文献
63.
应用0.5%环孢霉素A(cyclosporin A,CsA)滴眼治疗穿透性角膜移植术后发生免疫排斥患者16例(16只眼),治愈9只眼,好转6只眼,无效1只眼。随访5~24个月,其中2只眼因停药复发,1只眼于拆线后复发,继续用药或增加给药次数后治愈。研究表明0.5%CsA滴眼剂治疗术前移植床条件较好,角膜移植术后发生免疫排斥的病例可得到良好疗效;而对术前移植床条件较差,角膜移植术后发生免疫排斥的病例有一定的疗效。作者对眼局部应用CsA治疗角膜移植排斥的疗效和作用机理进行了讨论。 相似文献
64.
65.
Nicotine discrimination and self-administration in humans as a function of smoking status 总被引:2,自引:2,他引:0
Nicotine’s discriminative stimulus effects may be critical to understanding reinforcement of tobacco smoking. It is not known
whether regular nicotine exposure produces tolerance or sensitivity to these effects. In this study, male and female smokers
(n = 11) and never-smokers (n = 10) were trained to discriminate 20 μg/kg nicotine by nasal spray from placebo (0) on day 1. On day 2, both groups were
tested on generalization of this discrimination across intermittent presentations of 0, 3, 6, 12, and 20 μg/kg nicotine in
random order. Quantitative and quantal behavioral discrimination tasks, used in previous research, were employed. On day 3,
subjects were instructed to self-administer sprays from the 20 μg/kg nicotine versus 0 bottles in a concurrent-choice procedure.
All but one subject (female smoker) learned reliably to discriminate 20 μg/kg nicotine from placebo (≥ 80% correct) on day 1. Nicotine-appropriate responding on day 2 was attenuated in smokers versus never-smokers at 20 μg/kg
on the quantitative task and at 12 μg/kg on the quantal task, suggesting tolerance. There was no difference in responding
at other doses. Smokers also showed attenuated responses on the subjective measure of “head rush”, which was associated with
discrimination responding in both groups. Nicotine self-administration was significantly greater in smokers versus never-smokers,
who self-administered nicotine below chance levels, and was inversely related to discrimination behavior in never-smokers
but unrelated in smokers. Women smokers showed less change in nicotine-appropriate responding across generalization doses,
reported less confidence in discriminating training doses during acquisition on day 1, and tended to self-administer less
nicotine on day 3. These results indicate that smokers may become tolerant to the discriminative stimulus effects of nicotine,
perhaps promoting increased use.
Received: 1 October 1996/Final version: 28 January 1997 相似文献
66.
本文报道五例肿瘤患者在用抗癌药的治疗过程中,出现对心脏不同程度的毒性反应,并就有关几种抗癌药物的毒性作用机理及防治进行了讨论。 相似文献
67.
A detailed review of the adverse reactions of anticonvulsants is given, focusing on the definitions of drug toxicity, sources of information, patterns of durg utilization, pharmacokinetic variables and different mechanisms of action. The information available in the literature provides a wide spectrum of drug toxicity with no attempt at a practical definition of the reported events. This favors uncertainty among practising physicians, who are led to use the individual items with different attitudes. Suggestions are given for the evaluation, prevention and treatment of anticonvulsant drug toxicity.
Sommario La presente è una revisione critica dei diversi aspetti della tossicità dei farmaci antiepilettici. L'analisi della letteratura è condotta con particolare riferimento alle diverse fonti di informazione, ai pattern di utilizzo dei singoli principi attivi, ai dati farmacocinetici ed ai meccanismi di azione farmacologica sottostanti. L'ampio panorama che ne deriva non consente una definizione pratica degli effetti indesiderati degli anticonvulsivanti. Ciò determina incertezza e confusione nella pratica medica, con conseguente diversità di comportamenti. La rassegna si conclude con la presentazione di alcuni suggerimenti pratici per la valutazione, la prevenzione ed il trattamento della tossicità da anticonvulsivanti.相似文献
68.
当代大学生手淫行为比较普遍,很多大学生在上大学之前就养成了难以自控的手淫习惯。大学生手淫既影响了他们的身心健康,对他们在校园里健康成长成材也构成了严重的威胁。从思想与心里教育角度引导大学生正确对待手淫,促使他们养成积极健康的生活习惯,对他们将来人生的健康发展及营造和谐的校园风气具有重要的作用。文章论述了当代大学生手淫的根源、手淫危害、诱发因素、手淫动机及预防、矫治措施。 相似文献
69.
FRESH FROZEN PLASMA: IS IT FAREWELL? 总被引:1,自引:0,他引:1
JOHN CASH 《Vox sanguinis》1994,67(S3):121-124
70.
Karen A. Weissbecker 《Genetic epidemiology》1993,10(6):659-664
Hypertension, a major risk factor for cardiovascular diseases, is thought to be inherited to some extent. However, the nature of its genetic component remains unresolved. In the present study, data from a single large kindred (the HGAR1 pedigree) were used to search for evidence of single gene and multifactorial effects on diastolic blood pressure. Commingling analyses found that a mixture of three distributions fit the data significantly better than a single normal distribution, suggesting a major effect influencing diastolic blood pressure levels. However, segregation analysis, using regressive models, indicated that the transmission probabilities were not consistent with Mendelian expectations. There was no evidence of either major gene or polygenic effects on diastolic blood pressure levels in this family. © 1993 Wiley-Liss, Inc. 相似文献