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排序方式: 共有9125条查询结果,搜索用时 15 毫秒
71.
Estrogen receptor beta polymorphisms are associated with bone mass in women and men: the Framingham Study. 总被引:5,自引:0,他引:5
Amanda M Shearman David Karasik Kristen M Gruenthal Serkalem Demissie L Adrienne Cupples David E Housman Douglas P Kiel 《Journal of bone and mineral research》2004,19(5):773-781
ESR2 is expressed in bone cells, yet few studies have tested its variation for association with BMD, an important determinant of osteoporotic fractures. This was investigated in 723 men and 795 women from the Framingham study. Results show association of variation in this gene with BMD in both women and men. INTRODUCTION: Osteoporotic fracture risk is highly dependent on bone density, a quantitative multifactorial trait with a substantial genetic component. In contrast to the growing body of evidence that estrogen receptor alpha (ESR1) plays a role in bone metabolism, few studies have examined the estrogen receptor beta (ESR2) gene for association with BMD. An ESR2 CA repeat polymorphism, D14S1026, was associated with BMD in two small studies, each with <200 women. MATERIALS AND METHODS: The objective of this investigation was to assess whether D14S1026 or four other intronic polymorphisms were associated with BMD in 723 men and 795 women (mean age, 60 years) from the offspring cohort of the population-based Framingham Study. BMD was measured at the femur (neck, trochanter, and Ward's area) and the lumbar spine (L(2)-L(4)). RESULTS: In both women and men, there was significant association of D14S1026 genotype with measures of femoral but not spinal BMD. In addition, genotypes of two common single nucleotide polymorphisms, rs1256031 and rs1256059, in strong linkage disequilibrium with one another but not with D14S1026, were associated with measures of femoral BMD in men. The rs1256031 genotypes had up to a 4.0% difference in mean femoral BMD. An inferred rs1256031-D14S1026-rs1256059 haplotype C-23CA-T was significantly associated with reduced femoral BMD in women (p = 0.03, 0.003, and 0.01 for neck, trochanter, and Ward's area, respectively). Haplotype-based BMD differences ranged from 3.0% to 4.3%. CONCLUSIONS: We have observed significant association of common ESR2 variants with measures of femoral BMD in both men and women. 相似文献
72.
Brandt MM Wahl WL Yeom K Kazerooni E Wang SC 《The Journal of trauma》2004,56(5):1022-6; discussion 1026-8
BACKGROUND: We hypothesize that data collected from computed tomographic (CT) scans obtained for workup of chest or abdominal injuries provide data that are sufficient to screen for spinal fractures and will decrease the cost and time of spine evaluation after trauma. METHODS: We reviewed plain radiographs from 55 selected trauma patients who also underwent CT scanning of the chest, abdomen, and pelvis. We also timed the radiologic workup of 50 consecutive trauma patients to determine the time required to complete radiographic spine evaluation. RESULTS: Forty-seven patients had thoracolumbar fractures. Thirteen patients were found to have 33 thoracolumbar spine fractures identified by CT scan but not plain radiography. Fractures were found on initial trauma CT scans of the chest, abdomen, and pelvis obtained to evaluate for visceral injuries. No injuries seen on plain film were missed on CT scan. CONCLUSION: We recommend using the data acquired from CT scans to evaluate the spine, supplementing them with additional studies only when needed for further clarification. 相似文献
73.
In order to test the hypothesis that the increased myocardial collagen concentration in the older, spontaneously hypertensive (SH) rat is associated with altered T2 and T1, we performed in vitro studies of 70 left ventricles from 8-, 22-, and 33-week-old SH and Wistar-Kyoto (WKY) rats. We also measured the left ventricle/body weight (LV/BW) ratio (as a measure of hypertrophy), left ventricular water and fat content, and hydroxyproline concentration (as a measure of collagen). The LV/BW ration was not significantly different between 8-week-old SH rats and WKY rats but was significantly greater in SH rats than in WKY rats at 22 and 33 weeks of age. Comparing SH rats with WKY rats at 22 weeks of age, no significant difference existed in T1, T2, water content, or hydroxyproline concentration. However, at 33 weeks of age in SH rats compared with WKY rats, hydroxyproline concentration was significantly greater (4.3 +/- 0.6 mg/g, respectively; P less than .0005), water content was significantly greater (77.1% +/- 0.3% vs. 76.2% +/- 0.3%, respectively; P less than .0001), and T2 and T1 were significantly longer (T2: 52.6 +/- 2.1 msec vs. 48.6 +/- 2.2 msec, respectively; P less than .0001; T1: 656 +/- 14 msec vs. 619 +/- 12 msec, respectively; P less than .0001). In all SH rats combined, T2 and hydroxyproline concentration were significantly correlated (r = .63; P less than .0001). Thus, in SH rats, myocardial hypertrophy precedes increased collagen deposition. These data suggest that estimation of magnetic resonance relaxation times may permit noninvasive identification of increased myocardial collagen deposition independent from changes in myocardial hypertrophy. 相似文献
74.
Bein B Hanne P Hanss R Renner J Weber B Steinfath M Scholz J Tonner PH 《Anaesthesia》2004,59(11):1104-1110
Cardiac output (CO) determination based on partial CO(2) rebreathing has recently been introduced into clinical practice. The determination of flow is crucial for exact CO readings and the physical properties of xenon, i.e. high density and viscosity, may influence flow readings. This study compared echocardiography-derived CO measurements with the partial rebreathing method during total intravenous (TIVA) vs. xenon-based anaesthesia. Thirty-nine patients ASA physical status III undergoing aortic reconstruction were randomly assigned to receive either xenon (Xe, n = 20) or TIVA (T, n = 19) based general anaesthetic. Paired measurements were taken before xenon administration, after xenon administration, before and after clamping of the abdominal aorta and after declamping and at corresponding time points in the TIVA group. Data were analysed with a Bland-Altmann plot. Bias and precision were acceptable and comparable before xenon administration (T 0.54 +/- 0.92 l.min(-1) vs. Xe 0.11 +/- 1.1 l.min(-1)), but after xenon administration CO was largely overestimated by partial CO(2) rebreathing (T 0.04 +/- 0.91 l.min(-1) vs. Xe -4.0 +/- 2.1 l.min(-1)). In the TIVA group, bias and precision after declamping increased significantly (P < 0.01) compared to all time points except baseline. In its current application, the NICO cardiac output monitor appears to be inappropriate for determination of CO during xenon based anaesthesia. 相似文献
75.
Fox AM Pitzul K Bhojani F Kaplan M Moulton CA Wei AC McGilvray I Cleary S Okrainec A 《Surgical endoscopy》2012,26(5):1220-1230
Background
The cost implications of laparoscopic distal pancreatectomy (LDP) and a detailed breakdown of hospital expenditures has not been presented in the literature to date. This study aimed to compare hospital costs and short-term clinical outcomes between LDP and open distal pancreatectomy (ODP). 相似文献76.
CT and MRI-based Diagnosis of Craniocervical Dislocations: The Role of the Occipitoatlantal Ligament
Radcliff K Kepler C Reitman C Harrop J Vaccaro A 《Clinical orthopaedics and related research》2012,470(6):1602-1613
Background
Craniocervical dislocations are rare, potentially devastating injuries. A diagnosis of craniocervical dislocations may be delayed as a result of their low incidence and paucity of diagnostic criteria based on CT and MRI. Delay in diagnosis may contribute to neurological injury from secondary displacement resulting from instability. The purpose of this study was to define CT and MRI-based diagnostic criteria for craniocervical dislocations to facilitate early injury recognition and stabilization. 相似文献77.
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80.
Community-based treatment of acute uncomplicated bacterial rhinosinusitis with gatifloxacin. 总被引:2,自引:0,他引:2
Lawrence D Sher Michael D Poole Kristen Von Seggern Matthew A Wikler Susan C Nicholson George A Pankey 《Otolaryngology--head and neck surgery》2002,127(3):182-189
OBJECTIVE: We sought to evaluate gatifloxacin in adults with acute uncomplicated bacterial rhinosinusitis. STUDY DESIGN: TeqCES was an open-label, multicenter, noncomparative study of the safety and efficacy of gatifloxacin. More than 11,000 adult patients with acute uncomplicated rhinosinusitis received gatifloxacin 400 mg once daily for 10 days. RESULTS: Moraxella catarrhalis (91% beta-lactamase producers), Haemophilus influenzae (28% beta-lactamase producers), Streptococcus pneumoniae (18% intermediately resistant and 14% fully resistant to penicillin), and Staphylococcus aureus were the predominant pathogens isolated from purulent nasal discharge. More than 99% of rhinosinusitis pathogens isolated from the nasopharynx of patients meeting the clinical criteria for rhinosinusitis were susceptible to gatifloxacin. Among 10,353 patients whose clinical response could be determined, 91.6% were cured. Clinical cure rates exceeded 90% for the major pathogens. Gatifloxacin was well tolerated; drug-related adverse events that occurred in 1% or more of patients were nausea (4.4%), dizziness (1.8%), diarrhea (1.4%), and headache (1.0%). CONCLUSION: Gatifloxacin is effective for patients with acute bacterial rhinosinusitis in the community. 相似文献