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1.
Forty-nine children with asthma and their mothers were interviewed regarding their knowledge of asthma, factors that precipitated attacks, and how they attempted to reduce the probability of an attack. Many mothers and children were well aware of factors that precipitated attacks, but took little positive action to reduce attacks. The data suggest that much ill-health in asthmatic children could be reduced by improving education available to mothers and children. 相似文献
2.
Effect of nitric oxide on integrity, blood flow and cyclic GMP levels in the rat gastric mucosa: modulation by sialoadenectomy. 总被引:1,自引:0,他引:1 下载免费PDF全文
1. The effects of the nitrosothiol, S-nitroso N-acetylpenicillamine (SNAP) which liberates nitric oxide (NO), on ethanol-mediated gastric damage, blood flow and cyclic GMP levels in siaoloadenectomized (SALX) rats have been investigated. 2. Intraluminal instillation of ethanol (5-50% w/v) dose-dependently induced haemorrhagic damage and decreased NO synthase activity in the gastric mucosa. Both the extent of mucosal damage and inhibition of NO synthase activity were exacerbated in SALX rats. 3. Epidermal growth factor administration (5 and 10 micrograms kg-1, s.c.) reduced mucosal damage but did not restore NO synthase activity in ethanol-treated SALX rats. 4. SNAP infusion (0.01-1.0 micrograms kg-1 min-1, i.v.) attenuated haemorrhagic damage in ethanol-treated rats. The reduction in mucosal damage was significantly greater in SALX rats. 5. SNAP administration also caused an increase in gastric mucosal blood flow and cyclic GMP levels in control rats and both responses were augmented in SALX animals. 6. These data suggest that SALX is associated with increases in mucosal susceptibility to ethanol-mediated damage and reduces mucosal NO synthase activity. Epidermal growth factor does not appear to influence mucosal NO synthase in ethanol-treated rats. Furthermore, SALX augments the responsiveness of the gastric mucosa to NO administration. Therefore, factors from the salivary glands influence gastric NO formation and mucosal responsiveness to a NO donor. 相似文献
3.
This study reviews five cases of women with hyperthyroidism, three black women and two Hispanic women. Initially, two patients presented with voice changes, weight loss, and increased appetite. Only two patients presented with classical symptoms of hyperthyroidism. Examination showed all patients had diffusely enlarged thyroids and exaggerated reflexes. Two patients showed Graves'' opthalmopathy. 相似文献
4.
5.
Adenosine A1 receptor activation mediates suppression of (-) bicuculline methiodide-induced seizures in rat prepiriform cortex 总被引:1,自引:0,他引:1
P H Franklin G Zhang E D Tripp T F Murray 《The Journal of pharmacology and experimental therapeutics》1989,251(3):1229-1236
The protective effects of a series of stable adenosine analogs against generalized seizures initiated by focal injection of bicuculline methiodide into the rat prepiriform cortex (PPC) were studied by microinjection of these compounds into this brain area. The adenosine agonists, 5'-N-(ethyl)carboxamido-adenosine (NECA), cyclohexyladenosine, cyclopentyadenosine, 2-chloroadenosine and R- and S-phenylisopropyladenosine (R- and S-PIA), protected animals against seizures in a dose-dependent, and extremely potent manner. NECA, the most potent compound evaluated, completely prevented seizures at doses greater than or equal to 6.8 pmol. In contrast, heroic doses of the A2 selective ligand, 2-phenylaminoadenosine, afforded no protection against seizures. The rank order of potency of these compounds in suppressing seizures is as follows: NECA greater than cyclohexyladenosine greater than cyclopentyladenosine greater than or equal to R-PIA greater than 2-chloroadenosine greater than S-PIA much greater than 2-phenylaminoadenosine. These data suggest that the antiseizure activity of these compounds in the PPC results from activation of A1 adenosine receptors. Quantitative autoradiographic analysis of the distribution of tritiated adenosine agonists 30 min after microinjection in the PPC reveals that [3H]NECA diffuses to a significantly greater extent than R-[3H]PIA, which may contribute to the relatively greater potency of the former compound in suppressing bicuculline methiodide-induced seizures. These results suggest that adenosine A1 receptors may participate in the normal inhibitory regulation of the PPC, a forebrain area which may play a significant role in the pathobiology of epilepsy. 相似文献
6.
Philip J. Bossart M.D. F.A.C.E.P. Lenard Brunsdale M.D. Matt Hughes M.D. B. J. Manaster M.D. Ph.D. Anthony Doyle M.D. Kathy Murray M.D. David Tripp Ph.D. 《Emergency radiology》1997,4(1):26-29
To determine the utility of the lateral view of the chest in emergency department patients, records of all patients who had had 2-view chest x-rays ordered in the emergency department were reviewed retrospectively. A study radiologist recorded a reading of the posteroanterior (PA) radiograph alone. The lateral radiograph was then provided, along with the PA view, and a second reading was recorded. A comparison was then made between the first and second readings.A total of 417 sets of x-rays were included. The PA view alone successfully diagnosed or suspected 92% of pulmonary nodules, 95% of effusions, 97% of cases of emphysema, 98% of pneumonias, and 100% of cases of cardiomegaly, pulmonary edema, interstitial pulmonary disease, and atelectasis.In the emergency department patient population, lateral views of the chest have minimal diagnostic yield and therefore may be used selectively to safely decrease the amount of breast radiation exposure to young women. 相似文献
7.
R W Pinner B G Gellin W F Bibb C N Baker R Weaver S B Hunter S H Waterman L F Mocca C E Frasch C V Broome 《The Journal of infectious diseases》1991,164(2):368-374
Active surveillance for invasive meningococcal disease was conducted during 1986 and 1987 in six areas of the United States with a total population of approximately 34 million persons. The incidence of meningococcal disease was 1.3:10(5). The highest incidence of disease among the surveillance areas was in Los Angeles County (1.65:10(5). Neisseria meningitidis serogroups B and C caused about equal amounts of disease, which reflects a recent increase in the incidence of group C disease. Group C caused more than half of the cases of meningococcal disease in Los Angeles and Tennessee but less than one-third of the cases in Missouri and Oklahoma. Multilocus enzyme electrophoresis demonstrated that a group of closely related isolates of N. meningitidis was prevalent in Los Angeles during the surveillance period and was associated with an increased incidence of meningococcal disease there. 相似文献
8.
Irwin S. Johnsrude William M. Bogey Jr Michael D. Tripp 《Cardiovascular and interventional radiology》1994,17(6):336-338
Discovery of a postlumbosacral discectomy fistula between the right iliac artery and vein was obscured by an associated severe stricture of the infrarenal inferior vena cava in a 49-year-old man. During venous stenting for treatment of peripheral edema, the fistula was suspected because of faint pulsatile right iliac vein flow and increased O2 saturation of the venous blood. The suspicion was confirmed on subsequent iliac arteriography. Surgical closure of the fistula with arterial interposition grafting was then performed. The patient improved substantially. 相似文献
9.
Lipopolysaccharide (LPS) from Brucella abortus is less toxic than that from Escherichia coli, suggesting the possible use of B. abortus or LPS from B. abortus as a carrier in vaccines. 下载免费PDF全文
J Goldstein T Hoffman C Frasch E F Lizzio P R Beining D Hochstein Y L Lee R D Angus B Golding 《Infection and immunity》1992,60(4):1385-1389
Brucella abortus may be useful as a component of vaccines. This is because it possesses several unique properties as a carrier that enable it to stimulate human B cells even in the relative absence of T cells. Human immunodeficiency virus type 1 proteins conjugated to B. abortus could induce neutralizing antibodies against human immunodeficiency virus type 1. Recently we showed that the characteristics of lipopolysaccharide (LPS) derived from B. abortus are similar to those of the whole bacterium in that the LPS acts as a T-independent type 1 carrier in mice. In this study we wanted to determine whether LPS derived from B. abortus is associated with the adverse effects seen with other bacterial endotoxins. LPS purified from B. abortus by butanol extraction was shown to have less than 2% (wt/wt) contamination by protein and less than 1% (wt/wt) contamination by nucleic acids and to contain 1% (wt/wt) ketodeoxyoctanic acid. Compared with LPS derived from Escherichia coli, B. abortus LPS was 10,000-fold less potent in eliciting fever in rabbits, 268-fold less potent in killing D-galactosamine-sensitized mice, and 1,400-fold and 400-fold less potent in inducing interleukin-1 beta and tumor necrosis factor alpha production, respectively. These results suggest that B. abortus LPS is much less likely than the LPS from E. coli to evoke endotoxic shock; therefore, it may be feasible to incorporate B. abortus as a component of vaccines. 相似文献
10.
D J Herrmann R G Hamilton T Barington C E Frasch G Arakere O M?kel? L A Mitchell J Nagel G T Rijkers B Zegers 《Journal of immunological methods》1992,148(1-2):101-114
An international collaborative study was conducted at ten sites to examine the performance of enzyme immunoassays (EIAs) for the quantitation of IgG1, IgG2, IgG3, IgG4 and total IgG anti-Haemophilus influenzae type b (Hib) capsular polysaccharide in human serum. All groups used the same reagents: microtiter plates coated with polyribosylribitol phosphate (PRP) conjugated to poly-L-lysine (PLL), reference, control and test human sera, biotin-conjugated International Union of Immunological Societies (IUIS)-documented monoclonal anti-human IgG1-4 and IgG Pan detection antibodies, avidin-peroxidase and TMB substrate. Initial mixing of soluble PRP antigen or an equal volume of buffer with the 20 test sera prior to analysis confirmed PRP antigen specificity in all five EIAs with greater than 80% competitive inhibition at most sites. Positive correlation between the total IgG anti-Hib and sum of IgG1-4 anti-Hib was demonstrated (r2 = 0.99, Y = 1.13X -0.15). Good agreement was shown between the total IgG anti-Hib as measured by EIA and the total Hib-specific antibodies measured by the current radiolabeled antigen binding assay (r2 = 0.97, Y = 4.6X -5.8). Assay parallelism was demonstrated with an average interdilutional %CV of 22% and parallel dose-response curve slopes. The interdilutional %CVs were calculated as an average per sample of the variation of microgram/ml (corrected for dilution) at different dilutions per laboratory for all participating sites. The interlaboratory variation was the only performance parameter studied that exceeded the target level of 35% CV in all IgG1-4 and total IgG anti-Hib assays. IgG subclass distributions in the test sera demonstrated a predominance of IgG1 anti-Hib in the pediatric serum pools and IgG2 anti-Hib in the adult sera, with low but detectable levels of IgG3 and IgG4 anti-Hib in each group. 相似文献