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排序方式: 共有1259条查询结果,搜索用时 31 毫秒
981.
Otitis media-related antibiotic prescribing patterns, outcomes, and expenditures in a pediatric medicaid population 总被引:1,自引:0,他引:1
BACKGROUND: Treatment of otitis media is the most frequent reason for administering antibiotics to children in the United States. However, only limited data are available on medical effectiveness of antibiotic prescribing patterns for otitis media and their associated expenditures or the factors that influence antibiotic prescribing. METHODS: The study population consisted of 131 169 children during 1991 and 157 065 children during 1992 who were =13 years of age and enrolled in Colorado's fee-for-service Medicaid program. Among these children, 5127 (1991) and 7254 (1992) were enrolled in the cohort treated for a "new" episode of acute otitis media. An analysis using this cohort was performed to document the antibiotics used to treat a new episode of acute otitis media, factors influencing antibiotic selection, and the short-term outcomes of therapy. An analysis using the entire Medicaid population was performed to document the annual use of antibiotics for otitis, the associated antibiotic expenditures, and factors influencing antibiotic selection. RESULTS: In the cohort analysis, office-based physicians prescribed second- and third-generation cephalosporins more often than did physicians in other settings (17% vs 9.7% and 11.8%), whereas hospital clinics prescribed trimethoprim plus sulfamethoxazole more frequently than did office-based physicians (19.2% vs 7.1% and 10.9%). Family physicians prescribed second- and third-generation cephalosporins more often than did pediatricians (16.6% vs 12.3%) but trimethoprim plus sulfamethoxazole and erythromycin plus sulfisoxazole less often than did pediatricians (10.5% vs 17%). The average rate of prescribing a second course of antibiotics within 24 days after initial antibiotic treatment of a new acute otitis media episode was 11.6% when less expensive antibiotics (amoxicillin, trimethoprim plus sulfamethoxazole, or erythromycin plus sulfisoxazole) were prescribed, and 13.2% when more expensive antibiotics (cefaclor, amoxicillin plus clavulanate, or cefixime) were prescribed. The average adverse drug reaction rate was 5.9% when less expensive antibiotics were prescribed, compared with 6.1% when more expensive antibiotics were prescribed. In each of the two study years, amoxicillin accounted for almost half of the total antibiotic fills but only 9% to 10% of the expenditures. Low-cost antibiotics (amoxicillin, trimethoprim plus sulfamethoxazole, and erythromycin plus sulfisoxazole) were prescribed for 66% to 67% of the total fills and accounted for 21% of the total projected expenditures. More expensive antibiotics (cefaclor, cefixime, amoxicillin plus clavulanate) prescribed for 30% of the fills generated 76% to 77% of expenditures. Cefaclor, prescribed for 17% to 18% of the total fills, generated 43% to 45% of total antibiotic expenses. CONCLUSIONS: The findings of this study document a preference for amoxicillin as the initial antibiotic for a new episode of acute otitis media. Although there was a wide variation in the selection of antibiotics to treat otitis, the more expensive antibiotics were not associated with better outcomes. This wide variation has important financial implications because of differences in antibiotic costs. Changes in prescribing patterns among initially uncomplicated children that reduce the use of high-cost antibiotics could reduce expenditures substantially without compromising short-term outcomes. 相似文献
982.
Along with the growing requirement to reduce building carbon emissions, a need has arisen to find energy efficient means of improving the quality of indoor air. Indoor plants have been shown to be capable of reducing most air pollutants; however, practical numbers of potted plants will not have the capacity to control many forms of air pollution, especially CO2. Green walls are space-efficient means of increasing the density of indoor plants. We assessed an active green wall for its potential to reduce CO2 in chambers and a test room. Chlorophytum comosum and Epipremnum aureum were both effective cultivars for CO2 removal at light densities greater than 50 μmol m?2 s?1. Substrate ventilation increased the rate of CO2 draw down from chambers, possibly due to increased leaf gas exchange rates. Green walls were then tested in a 15.65-m3 sealed simulation room, allowing the calculation of clean air delivery rate (CADR) and air changes per hour (ACH) equivalents based on CO2 draw down. Rates of CO2 draw down were modest under typical brightly lit indoor conditions (50 μmol m?2 s?1); however, when light intensity was increased to relatively bright levels, similar to indoor conditions next to a window or with the addition of supplementary lighting (250 μmol m?2 s?1), a 1-m2 green wall was capable of significant quantifiable reductions of high CO2 concentrations within a sealed room environment. Extrapolating these findings indicates that a 5-m2 green wall containing C. comosum could balance the respiratory emissions of a full-time occupant. 相似文献
983.
P J Hajduk J Dinges J M Schkeryantz D Janowick M Kaminski M Tufano D J Augeri A Petros V Nienaber P Zhong R Hammond M Coen B Beutel L Katz S W Fesik 《Journal of medicinal chemistry》1999,42(19):3852-3859
The Erm family of methyltransferases confers resistance to the macrolide-lincosamide-streptogramin type B (MLS) antibiotics through the methylation of 23S ribosomal RNA. Upon the methylation of RNA, the MLS antibiotics lose their ability to bind to the ribosome and exhibit their antibiotic activity. Using an NMR-based screen, we identified a series of triazine-containing compounds that bind weakly to ErmAM. These initial lead compounds were optimized by the parallel synthesis of a large number of analogues, resulting in compounds which inhibit the Erm-mediated methylation of rRNA in the low micromolar range. NMR and X-ray structures of enzyme/inhibitor complexes reveal that the inhibitors bind to the S-adenosylmethionine binding site on the Erm protein. These compounds represent novel methyltransferase inhibitors that serve as new leads for the reversal of Erm-mediated MLS antibiotic resistance. 相似文献
984.
Two frequent missense mutations in Pendred syndrome 总被引:8,自引:3,他引:8
Van Hauwe P; Everett LA; Coucke P; Scott DA; Kraft ML; Ris-Stalpers C; Bolder C; Otten B; de Vijlder JJ; Dietrich NL; Ramesh A; Srisailapathy SC; Parving A; Cremers CW; Willems PJ; Smith RJ; Green ED; Van Camp G 《Human molecular genetics》1998,7(7):1099-1104
Pendred syndrome is an autosomal recessive disorder characterized by early
childhood deafness and goiter. A century after its recognition as a
syndrome by Vaughan Pendred, the disease gene ( PDS ) was mapped to
chromosome 7q22-q31.1 and, recently, found to encode a putative sulfate
transporter. We performed mutation analysis of the PDS gene in patients
from 14 Pendred families originating from seven countries and identified
all mutations. The mutations include three single base deletions, one
splice site mutation and 10 missense mutations. One missense mutation
(L236P) was found in a homozygous state in two consanguineous families and
in a heterozygous state in five additional non-consanguineous families.
Another missense mutation (T416P) was found in a homozygous state in one
family and in a heterozygous state in four families. Pendred patients in
three non-consanguineous families were shown to be compound heterozygotes
for L236P and T416P. In total, one or both of these mutations were found in
nine of the 14 families analyzed. The identification of two frequent PDS
mutations will facilitate the molecular diagnosis of Pendred syndrome.
相似文献
985.
986.
987.
GM Hafen C Hurst J Yearwood J Smith Z Dzalilov PJ Robinson 《BMC medical informatics and decision making》2008,8(1):44
Background
Cystic fibrosis is the most common fatal genetic disorder in the Caucasian population. Scoring systems for assessment of Cystic fibrosis disease severity have been used for almost 50 years, without being adapted to the milder phenotype of the disease in the 21st century. The aim of this current project is to develop a new scoring system using a database and employing various statistical tools. This study protocol reports the development of the statistical tools in order to create such a scoring system. 相似文献988.
The human corpus luteum: reduction in macrophages during simulated maternal recognition of pregnancy 总被引:2,自引:0,他引:2
It has been shown that immune cells, particularly macrophages, accumulate
in the corpus luteum during luteolysis. This study aimed to investigate the
effect of maternal recognition of pregnancy on the localization and numbers
of macrophages in the human corpus luteum. Corpora lutea (n = 12) were
obtained from normally cycling women at the time of hysterectomy and were
dated on the basis of serial urinary luteinizing hormone (LH) estimation.
In addition, corpora lutea (n = 4) were collected from women who had
received daily doubling doses of human chorionic gonadotrophin (HCG) to
mimic the hormonal changes of early pregnancy. Macrophages were localized
by immunohistochemistry using an anti-CD68 antibody. Steroidogenic cells,
steroidogenic cells of thecal origin and endothelial cells were identified
on serial sections by immunohistochemistry for 3beta-hydroxysteroid
dehydrogenase, 17alpha-hydroxylase and von Willebrand factor, respectively.
The luteal cells capable of responding directly to HCG were identified by
isotopic in-situ hybridization for messenger RNA encoding LH/HCG receptors.
Macrophages were localized primarily to the vascular connective tissue and
theca-lutein areas of the corpus luteum, although some were found in the
granulosa-lutein cell layer. Macrophage numbers increased throughout the
luteal phase to a maximum in the late- luteal phase (P < 0.05). Luteal
'rescue' with HCG was associated with a marked reduction in the numbers of
tissue macrophages when compared with those of the late-luteal phase (P
< 0.001). One of the effects of HCG during maternal recognition of
pregnancy is to prevent the normal influx of macrophages into the corpus
luteum. As LH/HCG receptors localized to the steroidogenic cells, this
implies a fundamental role for steroidogenic cell products in the control
of macrophage influx into the human corpus luteum.
相似文献
989.
AIM: To compare an ultrasonic height measuring device (Gulliver) with mechanical stadiometry and the classical "book and tape measure" method. METHODS: Blinded duplicate measurements of height were made on each of 14 children by a pair of observers using a stadiometer (H) and Gulliver (G). Height was measured on a further 18 children by parents and an auxologist using Gulliver and the book and tape method (TM), and the results were compared with those obtained with a single stadiometry measurement. Finally, measurement of a rigid metal box was made on 10 occasions by the three methods. RESULTS: In the group of 14 children, the mean difference (range) in height (H minus G) was +2.8 cm (+0.5 to +4.55 cm), with H giving a systematically higher value in 276 of 280 individual measurements. In the group of 18 children, height by H was greater than by G or TM in 47 of 52 individual measurements. The mean (SD) height of the box by H (61.60 (0.07) cm) was greater than by G (60.96 (0.15) cm; p < 0.001) but not TM (61.4 (0.16) cm; p > 0.05). G and TM produced three times less reliable estimations of height than H, but with a large difference in cost, and there was evidence of systematic underrecording of height by 0.5 cm with G. CONCLUSIONS: Stadiometry is precise and reproducible, and can detect true changes in height over one month periods in mid-childhood, and should remain the standard way of observing growth. The book and tape method can produce clinically acceptable quarterly estimations of height that can be performed in the home. 相似文献
990.
Measured haplotype analysis of the angiotensin-I converting enzyme gene 总被引:20,自引:5,他引:20
Keavney B; McKenzie CA; Connell JM; Julier C; Ratcliffe PJ; Sobel E; Lathrop M; Farrall M 《Human molecular genetics》1998,7(11):1745-1751
Linkage and segregation analysis have shown that circulating angiotensin-I
converting enzyme (ACE) levels are influenced by a major quantitative trait
locus that maps within or close to the ACE gene. The D variant of a 287 bp
insertion/deletion (I/D) polymorphism in intron 16 of the gene is
associated with high ACE levels and may also be related to increased risk
of cardiovascular disease. Multiple variants that are in linkage
disequilibrium with the I/D polymorphism have been described, but it is
unknown if any of these are directly implicated, alone or in combination
with as yet undiscovered variants, in the determination of ACE levels. An
analysis of 10 polymorphisms spanning 26 kb of the ACE gene revealed a
limited number of haplotypes in Caucasian British families due to strong
linkage disequilibrium operating over this small chromosomal region. A
haplotype tree (cladogram) was constructed with three main branches (clades
A-C) which account for 90% of the observed haplotypes. Clade C is most
likely derived from clades A and B following an ancestral recombination
event. This evolutionary information was then used to direct a series of
nested, measured haplotype analyses that excluded upstream sequences,
including the ACE promoter, from harbouring the major ACE-linked variant
that explains 36% of the total trait variability. Residual familial
correlations were highly significant, suggesting the influence of
additional unlinked genes. Our results demonstrate that a combined
cladistic/measured haplotype analysis of polymorphisms within a gene
provides a powerful means to localize variants that directly influence a
quantitative trait.
相似文献