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101.
We studied 364 index presentations to the Emergency Department of a children's hospital with a diagnosis of asthma. The admission rate for this group of children was about 31%. We developed a parsimonious multiple logistic regression model to predict asthma hospital admission based on asthma severity indicators. We then evaluated the model's predictive ability using two methods of cross-validation, using the same sample that was used for the predictive model, and using data from a split sample. The logistic regression model had a predictive accuracy of 90% (95% confidence interval 85–95%). The sensitivity and specificity were 86% and 88%, respectively. Cross-validation models confirmed that the predictive ability of the model was stable. In studies with limited sample sizes, it is possible to validate a model without setting aside a split sample for cross-validation. 相似文献
102.
Brent M Hanson Taylor P Kohn Alexander W Pastuszak Richard T Scott Jr Philip J Cheng James M Hotaling 《Asian journal of andrology》2021,(4):363-369
Many azoospermic men do not possess mature spermatozoa at the time of surgical sperm extraction.This study is a systematic review and meta-analysis evaluating o... 相似文献
103.
Benoxaprofen (BPF) induces a clinical photosensitivity which resembles idiopathic solar urticaria. This response is mediated by degranulation of mast cells. Since mast-cell degranulation is known to be modulated by phospholipid alteration, we examined the effect of BPF and ultraviolet radiation (UV) on phospholipid metabolism of C3H 10 T1/2 cells in culture. BPF + UVB (280-320 nm) induced release of [3H]arachidonic acid (AA) but did not alter the release of [3H]choline from prelabelled cells. This suggests that BPF photosensitizes phospholipase A2 activation. Such activation probably represents an integral step in the mechanism of BPF photosensitization of mast-cell degranulation. 相似文献
104.
We describe an additional case of spastic paretic hemifacial contracture, an uncommon condition characterized by sustained unilateral contraction of the facial muscles associated with mild ipsilateral facial paresis. This entity has only rarely been associated with multiple sclerosis (MS) and can be mistaken for hemifacial spasm. Early consideration of MS in the differential diagnosis of young patients admitted with these symptoms is essential. 相似文献
105.
B. H. Singsen A. S. Isaacson B. H. Bernstein M. J. Patzakis H. K. Kornreich K. K. King V. Hanson 《Arthritis \u0026amp; Rheumatology》1978,21(4):401-406
Fourteen children with juvenile rheumatoid arthritis and two with ankylosing spondylitis received 29 total hip replacements (THR). The ages at THR were 12 to 18 years, the median duration of prior hip disease was 7.1 years, and the minimum followup was one year (range 1–4 years, median 2.2 years). The primary indication for THR was pain in 5 hips and severe malposition or flexion contractures in 24 hips. (Sixteen of these also had some degree of pain.) All 29 hips demonstrated improved postoperative range of motion, and all were free of pain. In children, active rheumatic disease in other joints, prosthesis longevity, and possible lack of adequate motivation all merit special consideration prior to THR, but the results are encouraging. 相似文献
106.
Michael Sugarman Dennis G. Stobie Francisco P. Quismorio Roger Terry Virgil Hanson 《Arthritis \u0026amp; Rheumatology》1977,20(5):1125-1128
Five children with an inflammatory monarthritis due to penetration of the joint by plant thorns are presented. The clinical presentation was that of a transient acute synovitis followed by a relatively asymptomatic period, and later by chronic arthritis often after the thorn injury was forgotten. Histopathology demonstrated a granulomatous synovitis. Polarized light microscopy facilitated identification of the plant tissue within the synovium. Conservative medical therapy was ineffective, but surgical excision of the affected synovium resulted in normal joint function. The differential diagnosis of monarthritis in children is extensive, and awareness of this condition is necessary to elicit a comprehensive history and to avoid delay in treatment. 相似文献
107.
Lin PH Chronos NA Marijianowski MM Chen C Conklin B Bush RL Lumsden AB Hanson SR 《The Journal of surgical research》2003,112(1):84-90
PURPOSE: This study evaluates the effect of heparin-coated balloon-expandable stents on intimal hyperplasia following carotid artery stenting in a baboon model. MATERIALS AND METHODS: Balloon-expandable (Palmaz-Schatz) stents were placed in bilateral common carotid arteries in 26 male baboons (mean weight: 11.3 kg). In each animal, a heparin-coated (HC) carotid stent was placed on one side, whereas the contralateral carotid artery received an uncoated stent that served as a control. The carotid stents were harvested at 30 days (n = 13) and 90 days (n = 13). Arteriography was performed to assess the carotid patency, and intravascular ultrasound was used to determine neointimal and luminal areas. Histological, morphometric analysis, and scanning electron microscopy were performed in the stented carotid arteries. RESULTS: One animal was excluded in each of the 1-month and 3-month groups because of premature death. Ten control (83%) and 11 HC stents (92%) remained patent in the 30-day group. In contrast, 10 control (83%) and 10 HC stents (83%) remained patent in the 90-day group. Morphometric analysis of the 30-day group showed the HC-stented carotid arteries had larger luminal areas (13%, P < 0.05), less neointimal areas (38%, P < 0.05), less neointimal/media ratios (53%, P < 0.05), and equivalent medial areas (NS) when compared with the control group. Morphometric analysis of the 90-day data showed the HC-stented carotid arteries had less neointimal areas (38%, P < 0.05) and less neointimal/media ratios (48%, P < 0.05), whereas the luminal areas and medial areas remained equivalent (NS) when compared with the control group. CONCLUSIONS: Carotid stenting using heparin-coated stents reduces early intimal hyperplasia in a baboon model. This approach may represent a useful strategy for improving luminal patency in endovascular carotid intervention. 相似文献
108.
109.
Kojicic M Li G Hanson AC Lee KM Thakur L Vedre J Ahmed A Baddour LM Ryu JH Gajic O 《Critical care (London, England)》2012,16(2):R46-9
ABSTRACT: INTRODUCTION: Although pneumonia has been identified as the single most common risk factor for acute lung injury (ALI), we have a limited knowledge as to why ALI develops in some patients with pneumonia and not in others. The objective of this study was to determine frequency, risk factors, and outcome of ALI in patients with infectious pneumonia. METHODS: A retrospective cohort study of adult patients with microbiologically positive pneumonia, hospitalized at two Mayo Clinic Rochester hospitals between January 1, 2005, and December 31, 2007. In a subsequent nested case-control analysis, we evaluated the differences in prehospital and intrahospital exposures between patients with and without ALI/acute respiratory distress syndrome (ARDS) matched by specific pathogen, isolation site, gender, and closest age in a 1:1 manner. RESULTS: The study included 596 patients; 365 (61.2%) were men. The median age was 65 (IQR, 53 to 75) years. In total, 171 patients (28.7%) were diagnosed with ALI. The occurrence of ALI was less frequent in bacterial (n = 99 of 412, 24%) compared with viral (n = 19 of 55, 35%), fungal (n = 39 of 95, 41%), and mixed isolates pneumonias (n = 14 of 34, 41%; P = 0.002). After adjusting for baseline severity of illness and comorbidities, patients in whom ALI developed had a markedly increased risk of hospital death (ORadj 9.7; 95% CI, 6.0 to 15.9). In a nested case-control study, presence of shock (OR, 8.9; 95% CI, 2.8 to 45.9), inappropriate initial antimicrobial treatment (OR, 3.2; 95% CI, 1.3 to 8.5), and transfusions (OR, 4.8; 95% CI, 1.5 to 19.6) independently predicted ALI development. CONCLUSIONS: The development of ALI among patients hospitalized with infectious pneumonia varied among pulmonary pathogens and was associated with increased mortality. Inappropriate initial antimicrobial treatment and transfusion predict the development of ALI independent of pathogen. 相似文献
110.
Kanako J. Nagatomo Kevin A. Tompkins Hanson Fong Hai Zhang Brian L. Foster Emily Y. Chu 《Connective tissue research》2013,54(6):391-400
Bone morphogenetic proteins (BMPs) and BMP antagonists play a crucial role in the regulation of tooth development. One of the BMP extracellular antagonists, gremlin, is a highly conserved 20.7-kDa glycoprotein. Previously, researchers reported that transgenic mice overexpressing gremlin under the control of the osteocalcin promoter (gremlin OE) exhibit a skeletal phenotype and tooth fragility. To further define the tooth phenotype, teeth and surrounding supporting tissues, obtained from gremlin OE at ages of 4 weeks, 2 months, and 4 months, were examined. The histological results demonstrate that gremlin OE exhibit an enlarged pulp chamber with ectopic calcification and thinner dentin and enamel compared with wild-type control. In vitro studies using murine pulp cells revealed that gremlin inhibited BMP-4 mediated induction of Dspp. These data provide evidence that balanced interactions between BMP agonists/antagonists are required for proper development of teeth and surrounding tissues. It is clear that these interactions require further investigation to better define the mechanisms controlling tooth root formation (pulp, dentin, cementum, and surrounding tissue) to provide the information needed to successfully regenerate these tissues. 相似文献