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The reliability of auscultatory measurement of arterial blood pressure. A comparison of the standard and a new methodology 总被引:2,自引:0,他引:2
In 48 individuals with a wide range of arm circumferences blood pressure measured indirectly with two different cuffs was compared to direct intraarterial measurements. The two cuffs were a standard size cuff (12 X 35 cm) and a newly developed cuff, containing three rubber bags of different sizes, which automatically selects the appropriately sized bag in relation to arm circumference (Tricuff, Pressure Group AB, Sweden). The Tricuff correctly placed 42 of the 43 patients in the "normotensive" range, ie, diastolic blood pressure less than 90 mm Hg, whereas the standard cuff put only 33 of 44 patients in this range (P less than .005). The discrepancy was not only due to the expected better performance in patients with obese arms, but also in the subgroup of patients with arms in the range 22 to 31 cm, in which group both cuffs would measure blood pressure with a 12 cm wide rubber bag. The number of correctly identified "normotensive" patients was noticeably higher with the Tricuff than with the standard cuff (30/31 v 25/32, P = .053). The better specificity of the new cuff thus offers an improvement over the standard cuff. There are several potential clinical advantages of this, mainly that the risk of erroneously labelling normotensive individuals as hypertensive is reduced. 相似文献
54.
Sertoli cell monolayers were prepared from 19-day-old rat testes. On day 7 of culture cells were incubated for 24 hr in the presence or absence of ovine follicle stimulating hormone (oFSH). Cells were harvested, and adenylyl cyclase responses of the membrane particles to FSH, human chorionic gonadotropin (hCG), isoproterenol, and fluoride (F-) were examined in the presence of either GTP or the nonhydrolyzable guanylyl nucleotide GMP-P(NH)P. Culturing the cells in presence of FSH caused a hormone specific desensitization of FSH-responsive adenylyl cyclase, whereas responses to isoproterenol and fluoride were unaffected. Activation of Sertoli cell adenylyl cyclase by GTP and GMP-P(NH)P showed no difference between cells preincubated with or without FSH, indicating that FSH did not change the activity of the G/F (or N) component or its interaction with the catalytic subunit of the adenylyl cyclase. FSH-responsive adenylyl cyclase in cultured Sertoli cells has been shown to be selectively desensitized by homologous hormone. The mechanism may involve alteration or loss of the FSH receptor or changes in the "coupling" of the FSH receptors to the G/F component of the adenylyl cyclase, since there was no alteration in the guanylyl nucleotide and fluoride activation. 相似文献
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The present study was undertaken to evaluate possible beneficial effects of gammaglobulin treatment every 3 weeks during 6 months of 6-month to 2-year-old children. Every second of 44 children with recurrent acute otitis media (RAOM) received gammaglobulin, the other 22 served as controls. Nasal mucosal biopsy specimens were taken at 6-month intervals and analysed by light microscopy (LM) and scanning electron microscopy (SEM). Additional biopsies were obtained from another 15 children with RAOM and from 27 "healthy" children. No morphological differences in nasal mucosa could be demonstrated between the gammaglobulin treated and non-treated children. The structural changes observed in the first biopsy specimens usually persisted for at least 6 months, i.e. the study period, and were most prominent in the epithelium. Children with two or more episodes of acute otitis media (AOM) during the study period had more microabscesses compared to the children without any episode of AOM. Microabscesses were also more common in cases with secretory otitis media compared to cases with normal middle ear status. No morphological differences could be revealed related to the age of the children. Microabscesses, cell destruction and discontinuity of the epithelial lining were more common in children who harboured Branhamella catarrhalis in their nasopharynx. We conclude that intramuscular administration to children of gammaglobulin every 3 weeks during half a year neither improved their resistance to RAOM nor reduced the frequency or extent of structural changes in their nasal mucosa. 相似文献
56.
E. Pileblad P. S. Eriksson E. Hansson 《Journal of neural transmission (Vienna, Austria : 1996)》1991,86(1):43-49
Summary The concentration of the tripeptide glutathione (GSH) was measured in primary cultures of neurons and astroglial cells from rat cerebral cortex and brain stem. The concentration of GSH was found to be approximately 20 nmol/ mg protein in the neuronal culture from the cerebral cortex and ca. 40 nmol/ mg protein in the neuronal brain stem cultures. A GSH concentration of approximately 20 nmol/mg was observed in the astrocyte cultures from both brain regions. The possibility to increase the GSH concentration was tested by incubating the cultures in the presence of the GSH precursor -glutamylcysteine (-GC). In the cultured astrocytes -GC produced a dose-dependent increase in GSH. A similar increase was observed in the neuronal cultures, but this effect failed to reach statistical significance. 相似文献
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Kotarsky K Boketoft A Bristulf J Nilsson NE Norberg A Hansson S Owman C Sillard R Leeb-Lundberg LM Olde B 《The Journal of pharmacology and experimental therapeutics》2006,318(2):619-628
Here, the ligand binding, activation, and tissue distribution of the orphan G protein-coupled receptor (GPCR) GPR92 were studied. GPR92 binds and is activated by compounds based on the lysophosphatidic acid (LPA) backbone. The binding of LPA to GPR92 was of high affinity (K(D) = 6.4 +/- 0.9 nM) and led to an increase in both phosphoinositide hydrolysis and cAMP production. GPR92 is atypical in that it has a low sequence homology with the classic LPA(1-3) receptors (21-22%). Expression of GPR92 is mainly found in heart, placenta, spleen, brain, lung, and gut. Notably, GPR92 is highly expressed in the lymphocyte compartment of the gastrointestinal tract. It is the most abundant GPCR activated by LPA found in the small intestinal intraepithelial CD8+ cytotoxic T cells. 相似文献
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