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1.
James C Slaughter Thomas Lumley Lianne Sheppard Jane Q Koenig Gail G Shapiro 《Annals of allergy, asthma & immunology》2003,91(4):346-353
BACKGROUND: Exposure to air pollutants has been investigated as a possible cause of asthma attacks in children. OBJECTIVE: To investigate the short-term effects of air pollutants on a panel of 133 children with asthma who enrolled in the Childhood Asthma Management Program. METHODS: During screening, the children completed daily diary cards for an average of 58 days to indicate their medication use and asthma severity. We used ordinal logistic regression to compare the odds of a more serious relative to a less serious asthma attack, and we used a Poisson model to analyze medication use. In both analyses we accommodate dependence in the data and different periods of observation for study subjects. RESULTS: Our results indicate that a 10-microg/m3 increase in particulate matter less than or equal to 2.5 microm (PM2.5) lagged 1 day was associated with a 1.20 times increased odds of having a more serious asthma attack [95% confidence interval (CI), 1.05 to 1.37] and a 1.08-fold increase in medication use (95% CI, 1.01 to 1.15). A 10-microg/m3 increase in particulate matter less than or equal to 10 microm (PM10) increased the odds of a more serious asthma attack (odds ratio = 1.12; 95% CI, 1.04 to 1.22) and also increased medication use (relative risk = 1.05; 95% CI, 1.00 to 1.09). CONCLUSIONS: Increases in PM2.5 and PM10 are significantly associated with an increased risk of more severe asthma attacks and medication use in Seattle area children with asthma. We also found associations with carbon monoxide, but we believe that carbon monoxide is a marker for exposure to combustion byproducts. 相似文献
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Multiple genes encode nuclear factor 1-like proteins that bind to the promoter for 3-hydroxy-3-methylglutaryl-coenzyme A reductase. 总被引:37,自引:1,他引:36
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4.
RAFAEL BEYAR M.D. D.Sc. ARIEL ROGUIN M.D. JAAP HAMBURGER M.D. RE SAAIMAN M.D. ANTONIO L. BARTORELLI M.D. CARLO DiMARIO M.D. ANTONIO COLOMBO M.D. CHRISTIAN W. HAMM M.D. CHRISTOPHER J. WHITE M.D. J. MARCO M.D. PATRICK W. SERRUYS M.D. Ph.D. 《Journal of interventional cardiology》1997,10(4):277-286
The beStent is a new stainless steel, balloon-expandable mesh stent which has a unique serpentine design. Rotation of the unique low stress junctions upon expansion leads to orthogonal locking of the wires, maximizing radial strength and assuring zero shortening. The stent has delineating gold markers which assure precise positioning. We aim to present the initial acute results in a pilot registry for stent evaluation. Two hundred eighty-four stents were used in a total of 217 patients (age 57.9 ± 3.10 years; 178 males; 39 females) in seven centers, for variable indications. Stents of 15-, 25-, and 35-mm length were used. The arteries treated were the left anterior descending (n = 112, 42%), circumflex (n = 54, 20.2%), right coronary (n = 95, 35.5%), left main (n = 1, 0.4%), and vein graft (n = 5, 1.9%). Lesion types were: A in 42 patients (16.5%); B1 in 53 patients (20.7%); B2 in 81 patients (31.8%); and C in 79 patients (31%). One hundred fifty-nine patients required one stent, 40 patients required two stents, and 18 patients required three or more stents. Anticoagulation protocol included procedural heparin with aspirin with/without ticlopidine. Smooth angiographie results were obtained in all cases with no plaque herniation. Acute angiographic success was obtained in 97% of the patients, and acute clinical success in 95% of the patients. Complications within 30 days were: 3 deaths (1.4%) (2 noncardiac); 2 (0.9%) myocardial infarctions; and 2 (0.9%) stent thromboses. Therefore, the beStent is useful in treatment of complex lesions of variable length and complexity, providing excellent acute results with a low complication rate, in spite of unfavorable basic clinical and angiographie characteristics. 相似文献
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Microtubule dynamics in axons and dendrites. 总被引:9,自引:0,他引:9
We have investigated the stability, alpha-tubulin composition, and polarity orientation of microtubules (MTs) in the axons and dendrites of cultured sympathetic neurons. MT stability was evaluated in terms of sensitivity to nocodazole, a potent anti-MT drug. Nocodazole sensitivity was assayed by quantifying the loss of MT polymer as a function of time in 2 micrograms/ml of the drug. MTs in the axon and the dendrite exhibit striking similarities in their drug sensitivity. In both types of neurites, the kinetics of MT loss are biphasic, and are consistent with the existence of two types of MT polymer that depolymerize with half-times of MT polymer that depolymerize with half-times of approximately 3.5 min and approximately 130 min. We define the more rapidly depolymerizing polymer as drug-labile and the more slowly depolymerizing polymer as drug-stable. The proportion of MT polymer that is drug-stable is greater in axons (58%) than in dendrites (25%). On the basis of current understanding of the mechanism of action of nocodazole, we suggest that the drug-labile and drug-stable polymer observed in both axons and dendrites correspond to two distinct types of polymer that differ in their relative rates of turnover in vivo. In a previous study, we established that in the axon, these drug-stable and drug-labile types of MT polymer exist in the form of distinct domains on individual MTs, with the labile domain situated at the plus end of the stable domain (Baas and Black, J Cell Biol 111:495-509, 1990). Because of the great difference in drug sensitivity between the drug-labile and drug-stable MT polymer, we were able to dissect them apart by appropriate treatments with nocodazole. This permitted us to evaluate the drug-labile and drug-stable polymer in terms of polarity orientation and relative content of alpha-tubulin variants generated by posttranslational detyrosination or acetylation. In both the axon and the dendrite, the modified as well as unmodified alpha-tubulins are present in both drug-labile and drug-stable polymer, but at different levels. Specifically, the modified forms of alpha-tubulin are enriched in the drug-stable MT polymer compared to the drug-labile MT polymer. In studies on MT polarity orientation, we demonstrate that in axons, MTs are uniformly plus-end-distal, whereas in dendrites, MTs are non uniform in their polarity orientation, with roughly equal levels of the MTs having each orientation.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
7.
Perfluorochemicals as US contrast agents for tumor imaging and hepatosplenography: preliminary clinical results 总被引:3,自引:0,他引:3
Mattrey RF; Strich G; Shelton RE; Gosink BB; Leopold GR; Lee T; Forsythe J 《Radiology》1987,163(2):339-343
In animals, perfluorochemicals (PFCs) are effective ultrasound (US) contrast agents that produce hepatic, splenic, and tumor enhancement. The use of Fluosol-DA 20%, an emulsion of perfluorodecalin and perfluorotripropylamine, was studied in nine non-critically ill patients with cancer who had liver lesions. US studies without Fluosol were compared with studies obtained 24, 48, and 72 hours after Fluosol infusion. Vital signs and extensive laboratory analyses are performed before and after Fluosol infusion. Liver metastases from colonic, pancreatic, and gastric carcinoma exhibited rim or diffuse enhancement after a Fluosol dose of 1.6 g/kg or greater. Fluosol produced echogenic enhancement of the liver and spleen relative to kidney at a dose of 2.4 g/kg, allowing the detection of nonenhancing lesions. In addition, Fluosol at a dose of 1.6 g/kg or greater allowed detection of lesions not seen before contrast medium was administered in three of the seven patients studied. There was a mild increase in the level of serum glutamic oxaloacetic transaminase in two patients, one given 2.4 and the other 3.2 g/kg of Fluosol. Mild and transient allergic reactions without change in vital signs were experienced by two patients. 相似文献
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9.
Coralline hydroxyapatite bone graft substitutes: preliminary report of radiographic evaluation 总被引:1,自引:0,他引:1
A new bone graft substitute made by conversion of the calcium carbonate exoskeleton of reef-building sea coral into hydroxyapatite has recently become clinically available. The normal radiographic appearance of two forms of this material is described. In the immediate postoperative period, the exoskeletal architecture of these implants is readily appreciated. With graft incorporation over the ensuing months, their intrinsic structure is gradually lost in association with poor marginal definition. Evolving radiographic findings reflect the biocompatible nature of these implants, which provides the potential for ingrowth of native bone with preservation of the coralline scaffold, resulting in enhanced biomechanical properties. 相似文献
10.
Mutations in the retinal guanylate cyclase (RETGC-1) gene in dominant cone-rod dystrophy 总被引:3,自引:0,他引:3
Kelsell RE; Gregory-Evans K; Payne AM; Perrault I; Kaplan J; Yang RB; Garbers DL; Bird AC; Moore AT; Hunt DM 《Human molecular genetics》1998,7(7):1179-1184
The dominant cone-rod dystrophy gene CORD6 has previously been mapped to
within an 8 cM interval on chromosome 17p12-p13. The retinal- specific
guanylate cyclase gene (RETGC-1), which maps to within this genetic
interval and previously was implicated in Leber's congenital amaurosis, was
screened for mutations within this family and in a panel of small families
and individuals with various cone and cone- rod dystrophy phenotypes. A
missense mutation (E837D) was identified in affected members of the CORD6
family, as well as a second missense mutation (R838C) in three other
families with dominant cone-rod dystrophy. RETGC-1 is only the fourth gene
to be implicated in cone-rod dystrophy and this is the first report of
dominant mutations in this gene.
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