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51.
J G Classé 《Journal of the American Optometric Association》1986,57(1):66-71
In establishing the liability of optometrists for negligence the courts have applied the same standard of care that is imposed upon other health care professionals, holding that optometrists must employ the minimum degree of skill, care and learning that is ordinarily exhibited by members of the profession who are in good standing. The leading cases establishing this standard have involved glaucoma, retinal detachment, and intraocular tumors. Optometrists have also been held liable under product liability law for injuries caused by ophthalmic lenses, which illustrates the trend toward strict liability. Other cases have involved the doctrine of informed consent. 相似文献
52.
Melatonin, a pineal hormone, released photoperiodically, was administered systemically in rats, previously implanted with semimicroelectrodes into six different brain structures. The multiunit electrical activity of these structures was recorded for 10 min before and 60 min after melatonin administration in unanesthetized, freely moving rats. Different melatonin doses (100, 200, 500, and 1000 micrograms/kg) produced changes in the electrical activity of all tested structures. However, amygdala, rostral hypothalamus and mesencephalic reticular formation showed the most important changes. The main effect induced by melatonin was a dose-related decrease of the spontaneous electrical activity. The significance of these effects is discussed within the context of the behavioral and endocrinological effects of melatonin. 相似文献
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55.
A. Jaén J. Sunyer X. Basagaña S. Chinn† J. P. Zock J. M. Antó‡ P. Burney† 《Clinical and experimental allergy》2002,32(12):1713-1719
BACKGROUND: The role of atopy in the evolution to chronic obstructive disease remains controversial. AIM: We aimed to assess the association between individual sensitization to common allergens and lung function. METHOD: We analysed data from 12,687 subjects aged 20 to 44 years, from 34 centres in 15 countries participating in the European Community Respiratory Health Survey (ECRHS). Participants performed a blood test, lung function test, methacholine challenge, and answered an administered questionnaire. The relationships between specific IgE, FEV1 and FEV1/FVC ratio were assessed for each study centre stratified by sex, followed by random effects meta-analysis. RESULTS: Asthmatics sensitized to house dust mite had a lower FEV1 (-119 mL in women and -112 mL in men) and FEV1/FVC ratio (-1.95%, and -2.48%) than asthmatics without sensitization. Asthmatics sensitized to cat had a lower FEV1 (statistically significant for women only) and a lower FEV1/FVC ratio. Asthmatic women sensitized to grass had a lower FEV1 and a lower ratio, and those sensitized to Cladosporium had a lower FEV1. A weak association was found with sensitization to cat and to Cladosporium among non-asthmatic women, which disappeared after adjusting for BHR. CONCLUSION: We conclude that atopy was related to a lower lung function, which was only apparent among asthmatics. This relationship was explained by specific sensitization to cat and to house dust mite, the latter being homogeneous across areas. 相似文献
56.
P Leprince F Heloire B Eymard P Léger D Duboc A Pavie 《The Journal of heart and lung transplantation》2002,21(7):822-824
A 28-year-old male patient diagnosed with Becker muscular dystrophy (BMD)-associated cardiomyopathy was successfully bridged to transplantation with the Cardiowest total artificial heart. Dramatic improvement of muscular functional status occurred following transplantation. 相似文献
57.
The triphalangeal thumb-brachyectrodactyly syndrome is a very rare autosomal dominant disorder of unknown etiology characterized by an unusual pattern of limb malformations: triphalangeal thumbs and brachyectrodactyly in the hands, and ectrodactyly in the feet. In a previous report, we described the clinical and radiographical features of three related subjects with the disease and suggest that due to the unusual combination of limb defects and to its phenotypic similarity with the limb malformative pattern induced by disrupting the Hoxd13 gene in mouse, the triphalangeal thumb-brachyectrodactyly syndrome might be caused by mutations in a HOX gene. After sequencing the entire coding region of HOXD13 and the highly conserved homeodomain encoding region of HOXA13, we do not detect any deleterious mutation in any of the patients excluding that alterations at these sequences are responsible for the disease. Mutations in regulatory regions of these genes or in other genes involved in limb development might be responsible for the disease. 相似文献
58.
C R Plata-Salamán 《Brain research bulletin》1991,27(5):737-738
Intracerebroventricular (ICV) microinfusion of recombinant human interleukin-1 beta (rhIL-1 beta, 0.125 to 2.0 ng/rat) dose-dependently suppressed 2 h and nighttime food intake in rats. The following daytime food intake did not change or increased. ICV infusion of bovine serum albumin (BSA), or heat-treated rhIL-1 beta had no effect on food intake. Pretreatment with dexamethasone (200 micrograms/rat, intraperitoneal) blocked the food intake suppression induced by low doses of rhIL-1 beta. This ability of dexamethasone, a synthetic corticosteroid, may have potential therapeutic implications in acute and chronic pathological processes associated with increased levels of IL-1 and appetite suppression. 相似文献
59.
Galanin-like immunoreactivity has been visualized in nerve fibers in the islets of Langerhans, suggesting an involvement of
galanin in the neural regulation of islet function. In this study, we investigated the effects of galanin on basal and stimulated
insulin and glucagon secretion by infusing the peptide at three different dose rates in rats. We also studied the direct effect
of galanin on insulin secretion from freshly isolated rat islets. At 320 pmol/kg/min, but not at 20 or 80 pmol/kg/min, galanin
lowered basal plasma insulin levels. In contrast, basal plasma glucagon levels were lowered by galanin already at 20 and 80
pmol/kg/min. Furthermore, galanin inhibited both glucose- and arginine-induced insulin release at all three dose levels, whereas
arginine-induced glucagon release was not affected by galanin. Glucose-stimulated insulin secretion from isolated rat islets
was dose-dependently suppressed by galanin (10-6-10-8M). Therefore, it is concluded that galanin in rats inhibits insulin secretion, both in vivo and in vitro, and that at lower
dose levels, the peptide also inhibits basal glucagon release. 相似文献
60.