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101.
Philip E Benson C W Ian Douglas Michael V Martin 《American journal of orthodontics and dentofacial orthopedics》2004,126(3):325-330
The objective of this study was to investigate the effect of fluoridated elastomeric ligatures on the microbiology of local dental plaque in vivo. This randomized, prospective, longitudinal, clinical trial had a split-mouth crossover design. The subjects were 30 patients at the beginning of their treatment with fixed orthodontic appliances in the orthodontic departments of the Liverpool and the Sheffield dental hospitals in the United Kingdom. The study consisted of 2 experimental periods of 6 weeks with a washout period between. Fluoridated elastomers were randomly allocated at the first visit to be placed around brackets on tooth numbers 12, 11, 33 or 22, 21, 43. Nonfluoridated elastomers were placed on the contralateral teeth. Standard nonantibacterial fluoridated toothpaste and mouthwash were supplied. After 6 weeks (visit 2), the elastomers were removed, placed in transport media, and plated on agar within 2 hours. Nonfluoridated elastomers were placed on all brackets for 1 visit to allow for a washout period. At visit 3, fluoridated elastomers were placed on the teeth contralateral to those that received them at visit 1. At visit 4, the procedures at visit 2 were repeated. Samples were collected on visits 2 and 4. A logistic regression was performed, with the presence or absence of streptococcal or anaerobic growth as the dependent variable. A mixed-effects analysis of variance was carried out with the percentage of streptococcal or anaerobic bacterial count as the dependent variable. The only significant independent variables were the subject variable (P =<.001) for the percentage of streptococcal and anaerobic bacterial count and the visit variable for the percentage of streptococcal count (P =<.001). The use of fluoridated or nonfluoridated elastomers was not significant for percentage of either streptococcal (P =.288) or anaerobic count (P =.230). Fluoridated elastomers are not effective at reducing local streptococcal or anaerobic bacterial growth after a clinically relevant time in the mouth. 相似文献
102.
Michael Robson Isabelle Côte Ian Abbs Geoffrey Koffman David Goldsmith 《American journal of transplantation》2003,3(3):324-327
Thrombotic microangiopathy is a rare but important finding in the context of organ transplantation. Acute renal insufficiency in the setting of hemolysis and thrombocytopenia, a triad that constitutes 'hemolytic uremic syndrome', can be associated with, or triggered by, conditions such as verocytotoxin-producing Escherichia coli, viral infections, malignant hypertension, scleroderma, allograft rejection, lupus erythematosus, pregnancy, and medications including mitomycin C, calcineurin inhibitors, and oral contraceptives. After renal transplantation, it can occur, as either a de novo episode, or recurrent disease. Calcineurin inhibitors have long been associated with post-transplantation thrombotic microangiopathy. Sirolimus has been used as a primary immunosuppressant in patients transplanted with a history of earlier hemolytic-uremic syndrome, and also as rescue therapy in patients with calcineurin-inhibitor-associated thrombotic microangiopathy. We describe four cases where there was significant thrombotic microangiopathy in the context of contemporaneous or contiguous calcineurin inhibitor and sirolimus usage. As the intrarenal cyclosporin concentration is thought to be significantly elevated when cyclosporin and sirolimus are used together, this may explain these findings, and mandates caution in their co-administration. 相似文献
103.
Wendy Packman Joselyn Fine Beth Chesterman Kelly vanZutphen Rama Golan Michael Amylon 《Children's Health Care》2004,33(3):201-215
This research was conducted at a summer camp for siblings of children with cancer. The camp is designed to address emotional problems, provide peer interaction and validation, and bolster siblings' self-esteem. Standardized measures assessing posttraumatic stress, anxiety, quality of life, and self-esteem were administered to 77 siblings (ages 6-17) prior to attending camp and again 3 months after camp. From pre- to post-camp, the siblings reported statistically significant decreases in symptoms of posttraumatic stress and anxiety, and statistically significant improvements in quality of life and self-esteem. These preliminary findings are encouraging and suggest the value of camp as a psychological intervention and provide a model for other pediatric cancer facilities designing intervention programs for siblings. 相似文献
104.
Ventilation imaging of the lung: Comparison of hyperpolarized helium-3 MR imaging with Xe-133 scintigraphy 总被引:1,自引:0,他引:1
Talissa A. Altes MD Patrice K. Rehm MD Frank Harrell PhD Michael Salerno PhD Thomas M. Daniel MD Eduard E. de Lange MD 《Academic radiology》2004,11(7):729-734
RATIONALE AND OBJECTIVES: To compare hyperpolarized helium-3 (HHe) magnetic resonance imaging (MRI) of the lung with standard Xe-133 lung ventilation scintigraphy. MATERIALS AND METHODS: We performed a retrospective review of 15 subjects who underwent HHe MRI and Xe-133 lung ventilation imaging. Coronal MRI sections were acquired after a single inhalation of HHe gas, and standard posterior planar lung ventilation scintigraphy was performed during continuous breathing of Xe-133 gas. The first breath scintigram of each patient was compared with a composite MR image composed of the sum of the individual MR images and with the individual helium-3 MR images. Ventilation defects on the two imaging modalities were compared for size, conspicuity, and concordance in presence and location. Assessment was done separately for each of four lung quadrants. RESULTS: Comparing the composite HHe MR images with Xe-133 scintigraphy, ventilation defect size, conspicuity and concordance were the same in 67% (40/60), 63% (38/60), and 62% (37/60) quadrants, respectively. Comparing the individual HHe MR image sections with the Xe-133 ventilation scan, there was concordance between the ventilation defects in 27% (16/60) of quadrants. More defects were identified on the individual HHe MR images in 62% (37/60) of quadrants. CONCLUSION: There was good agreement between composite HHe MR image and first breath Xe-133 scintigraphic images, supporting the widely held assumption that HHe MRI likely depicts first breath lung ventilation. 相似文献
105.
106.
107.
Osteochondral Fracture of the Fourth Metatarsal Head Treated by Open Reduction and Internal Fixation
Praveen K.R. Mereddy MBBS MSOrth DNB Orth MRCSEd Andrew Molloy MBchB MRCS FRCS Michael S. Hennessy BSc MBchB FRCSEd 《The Journal of foot and ankle surgery》2007,46(4):320-322
Fracture of the metatarsal head is uncommon, and reports of isolated osteochondral fracture of the metatarsal head are rare. Because of the distal location of the fracture, it is difficult to achieve and maintain reduction, and potential complications include avascular necrosis and subchondral fatigue fracture. The authors present a case of an osteochondral fracture in a 40-year-old man, which was treated by open reduction and internal fixation with a single twist-off screw, with good results 12 months postoperatively. 相似文献
108.
109.
Michael T Fitch David E Manthey Henderson D McGinnis Bret A Nicks Manoj Pariyadath 《BMC medical education》2008,8(1):38
Background
Skin and soft tissue infections are increasingly prevalent clinical problems, and it is important for health care practitioners to be well trained in how to treat skin abscesses. A realistic model of abscess incision and drainage will allow trainees to learn and practice this basic physician procedure. 相似文献110.
Michelle L. DeOliveira Timothy M. Pawlik Ana L. Gleisner Lia Assumpcaom Gaspar J. Lopes-Filho Michael A. Choti 《Journal of gastrointestinal surgery》2007,11(8):970-976
Survival after resection of colorectal liver metastases has traditionally been associated with clinicopathologic factors.
We sought to investigate whether echogenicity of colorectal liver metastasis as assessed by intraoperative ultrasound (IOUS)
was a prognostic factor after hepatic resection. Prospective data on tumor IOUS appearance were collected in 84 patients who
underwent hepatic resection for colorectal liver metastasis. Images were digitally recorded, blindly reviewed, and scored
for echogenicity (hypo-, iso-, or hyperechoic). The median tumor number was 1 and the median tumor size was 5.0 cm. At the
time of surgery, the IOUS appearance of the colorectal liver metastases were hypoechoic in 35 (41.7%) patients, isoechoic
in 37 (44.0%) patients, and hyperechoic in 12 (14.3%) patients. Traditional clinicopathologic prognostic factors were similarly
distributed among the three echogenicity groups (all p > 0.05). Patients with a hypoechoic lesion had a significantly shorter median survival (30.2 months) compared with patients
who had either an isoechoic (53.2 months) or hyperechoic (42.3 months) lesion (p = 0.005). The 5-year survival after hepatic resection of colorectal liver metastasis was also associated with the echogenic
appearance of the lesion (hypoechoic 14.4 vs isoechoic 37.4 vs hyperechoic 46.2%) (p < 0.05). Intraoperative ultrasound echogenicity should be considered a prognostic factor after hepatic resection of metastatic
colorectal cancer.
This study was presented at the 47th annual meeting of The Society for Surgery of the Alimentary Tract, Los Angeles, CA, USA,
22 May 2006. 相似文献