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排序方式: 共有1145条查询结果,搜索用时 15 毫秒
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Michael D. Cabana David Bruckman Susan L. Bratton Alex R. Kemper Noreen M. Clark 《The Journal of asthma》2003,40(7):741-749
Background. The National Heart, Lung, and Blood Institute (NHLBI) guidelines recommend that patients receive a follow-up outpatient asthma visit after being discharged from an emergency department (ED) for asthma. Objective. To measure the frequency of follow-up outpatient asthma visits and its association with repeat ED asthma visit. Design. We conducted a retrospective cohort study of children with asthma using claims data from a university-based managed care organization from 01 1998 to 10 2000. We performed a multivariate survival analysis using Cox proportional hazards model to determine the effect of follow-up outpatient asthma visits on the likelihood of a repeat ED asthma visit, after controlling for severity of illness, patient age, gender, insurance, and the specialty of the primary care provider. Results: A total of 561 children had 780 ED asthma visits. Of these, 103 (17%) had a repeat ED asthma visit within 1 year. Almost two-thirds of children (66%) did not receive outpatient follow-up for asthma within 30 days of an ED asthma visit. Outpatient asthma visits within 30 days of an ED asthma visit are associated with an increased likelihood (relative risk = 1.80; 95% confidence interval 1.19, 2.72) for repeat ED asthma visits within 1 year. Conclusions. Most patients do not have outpatient follow-up after an ED asthma visit. However, those patients that present for outpatient follow-up have an increased likelihood for repeat ED asthma visits. For the primary care provider, these outpatient follow-up visits signal an increased risk that a patient will return to the ED for asthma and are a key opportunity to prevent future ED asthma visits. 相似文献
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H. Noreen L. Steiner M. Davidson S. Johnson M. Segall A. B. Begovich 《Tissue antigens》1997,49(5):512-516
Six new DPB1 alleles were identified by PCR-SSOP methodologies in the course of a retrospective study of the role of HLA matching in the outcome of unrelated donor bone marrow transplantation. Sequencing confirmed that five of these alleles (DPB1*5901, *6801, *7101, *7201, and *7301) represent novel combinations of previously described sequence motifs in the variable regions of DPB1; the sixth (DPB1*7001) appears to result from a novel point mutation. These data support previous observations which suggest that multiple mechanisms, including segmental exchange and mutation, appear to be responsible for generating sequence diversity at the DPB1 locus. The extremely low discrepancy rate of 0.1% between the two laboratories which typed the samples, and the ability to predict the new sequences from probe hybridization patterns, indicate that SSOP is an accurate and efficient method for studying polymorphism at DPB1. 相似文献
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We report an infant with Pfeiffer syndrome (acrocephalosyndactyly type V) and a solid cartilaginous trachea lacking rings. This airway abnormality has been reported in a child with Crouzon syndrome but has not been described in Pfeiffer syndrome. 相似文献
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Chen Sharon A. Perlman Andrew J. Spanski Noreen Peterson C. Matthew Sanders Steven W. Jaffe Robert Martin Mary Yalcinkaya Tamir Cefalo Robert C. Chescheir Nancy C. Menard Mary K. Mordenti Joyce 《Pharmaceutical research》1993,10(6):834-838
The pharmacokinetics of recombinant human relaxin (rhRlx) after intravenous (iv) bolus administration and the absorption of rhRlx after intracervical or intravaginal administration were determined in nonpregnant women. The study was conducted in two parts. In part I, 25 women received 0.01 mg/kg rhRlx iv. After a minimum 7-day washout period, these women were dosed intracervically (n = 10) or intravaginally (n = 15) with 0.75 or 1.5 mg rhRlx, respectively, in 3% methylcellulose gel. Part II was a double-blind, randomized, three-way crossover study in 26 women. At 1-month intervals, each woman received one of three intravaginal treatments consisting of 0 (placebo), 1, or 6 mg rhRlx in 3% methylcellulose gel. The serum concentrations of relaxin following iv administration were described as the sum of three exponentials. The mean (±SD) initial, intermediate, and terminal half-lives were 0.09 ± 0.04, 0.72 ± 0.11, and 4.6 ± 1.2 hr, respectively. Most of the area under the curve was associated with the intermediate half-life. The weight-normalized clearance was 170 ± 50 mL/hr/kg. The observed peak concentration was 98 ± 29 ng/mL, and the weight-normalized initial volume of distribution was 78 ± 40 mL/kg, which is approximately equivalent to the serum volume. If central compartment elimination was assumed, the volume of distribution at steady state (V
ss/W) was 280 ± 100 mL/kg, which is approximately equivalent to extracellular fluid volume. V
ss/W could be as large as 1300 ± 400 mL/kg without this assumption. After intravaginal administration of the placebo gel, endogenous relaxin concentrations were evident (i.e., 20 pg/mL) in 9 of the 26 women (maximum concentrations, 23–234 pg/mL). A similar proportion of women (approximately 35–40%) exhibited measurable serum concentrations of relaxin following intravaginal rhRlx treatment; this proportion increased to 90% following intracervical rhRlx treatment. For both routes of administration, the maximum serum concentrations of relaxin were usually within the range of values observed for endogenous relaxin, suggesting that the absorption of rhRlx was minimal. 相似文献
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Nutritional predictors of insulin-like growth factor I and their relationships to cancer in men. 总被引:4,自引:0,他引:4
Edward Giovannucci Michael Pollak Yan Liu Elizabeth A Platz Noreen Majeed Eric B Rimm Walter C Willett 《Cancer epidemiology, biomarkers & prevention》2003,12(2):84-89
The insulin-like growth factor (IGF) axis may play opposing roles in health and disease.The age-related declines in growth hormone and IGF-I may be associated with potentially deleterious changes in body composition and functioning, but recent studies suggest that IGF-I levels may be related to risk of prostate, colorectal, premenopausal breast, and possibly other cancers. Thus, we studied dietary influences on plasma IGF-I and IGF-I:IGF-binding protein-3 ratio in 753 men in the Health Professionals Follow-Up Study who completed a food frequency questionnaire. In this generally well-nourished population of middle-aged to elderly men, plasma IGF-I and IGF-I:IGF-binding protein-3 molar ratio tended to increase with higher intake of protein and minerals, including potassium, zinc, magnesium, calcium, and phosphorus. Men with relatively high intakes of total protein (top quintile) and minerals (top quintile of the five minerals combined) had a 25% higher mean plasma level of IGF-I compared with those in the low quintiles simultaneously. The major sources of animal protein, including milk, fish, and poultry, but not red meat, as well as total vegetable protein, were associated with an increase in IGF-I levels. Energy intake was positively related to plasma IGF-I level but only in men with body mass index <25 kg/m(2). The age-related decline in plasma IGF-I may be exacerbated by low intakes of protein and minerals. The potential role of these dietary factors on cancer risk through altering IGF-I levels requires study. 相似文献
10.
MRI characteristics of the neurocentral synchondrosis 总被引:3,自引:0,他引:3
Rajwani T Bhargava R Moreau M Mahood J Raso VJ Jiang H Bagnall KM 《Pediatric radiology》2002,32(11):811-816
BACKGROUND AND OBJECTIVES: The neurocentral synchondrosis (NCS) is a cartilaginous growth plate that since the early 1900s has been implicated as a potential cause of adolescent idiopathic scoliosis (AIS). Previous studies have focused only on the closure age without characterizing normal NCS development. Using MRI, the normal development of the NCS image can be characterized, and the stages preceding the disappearance of this image can be specified. METHODS: A total of 405 NCSs were visualized in 11 normal pediatric patients using T1 and T2 transverse and sagittal MRI views. The images were correlated and the variety of images recorded to categorize the NCS into developmental stages. RESULTS: The development of the NCS was categorized into five developmental stages. The image of the NCS became absent in a specific pattern along the vertebral column, first in the cervical region (age 6), then in the lumbar region (age 12), and finally in the thoracic region (age 14). CONCLUSION: The normal development of the NCS at the level of individual vertebrae and also along the vertebral column as a whole was determined using MRI. These patterns of development are valuable and necessary to evaluate the role of the NCS in pathological conditions. 相似文献