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41.
Hossam B El-Zawawy Corey S Gill Rick W Wright Linda J Sandell 《Journal of orthopaedic research》2006,24(12):2150-2158
Smoking delays the healing process and increases morbidity associated with many common musculoskeletal disorders, including long bone fracture. In the current study, a murine model of tibial fracture healing was used to test the hypothesis that smoking delays chondrogenesis after fracture. Mice were divided into two groups, a nonsmoking control group and a group exposed to cigarette smoke for 1 month prior to surgical tibial fracture. Mice were euthanized at 7, 14, and 28 days after surgery. The outcomes measured were immunohistochemical staining for type II collagen protein expression as a marker of cartilage matrix and proliferating cell nuclear antigen (PCNA) staining to measure proliferation at the site of injury. Toluidine blue staining and histomorphometry were used to quantify areas of cartilaginous and noncartilaginous fracture callus. Radiographs were analyzed for evidence of remodeling after injury. At day 7 after injury, mice exposed to cigarette smoke had a smaller fracture callus with less cartilage matrix compared to controls. Proliferation was present at high levels in both groups at this time point, but proliferating cells had a more immature morphology in the smoking group. At day 14, chondrogenesis was more active in smokers compared to controls, while a higher percentage of bone was present in the control animals. At day 28, X-ray analysis revealed a larger fracture callus remaining in the smoking animals. Together, these findings show that the chondrogenic phase of tibial fracture healing is delayed by smoking. This study represents, to our knowledge, the first analysis of molecular and cellular mechanisms of healing in a smoking mouse fracture model. 相似文献
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A L Harris S Nicholson R Sainsbury C Wright J Farndon 《Journal of the National Cancer Institute. Monographs》1992,(11):181-187
Analysis of epidermal growth factor receptor (EGFr) and estrogen receptor (ER) was performed on tumor samples from 231 patients with operable breast cancer followed for up to 6 years after surgery. The median duration of follow-up in patients still alive at the time of analysis was 45 months. Thirty-five percent of patients (82) had tumors greater than 10 fmol/mg of 125I-EGF binding (EGFr+) and 47% (109) had cystolic ER concentration greater than 5 fmol/mg (ER+), with a marked inverse relationship between EGFr and ER (P less than .00001). EGFr was second only to axillary-node status as a prognostic marker for all patients in terms of both relapse-free and overall survival in univariate analysis (P less than .001, log-rank EGFr + v EGFr-). For patients with histologically negative axillary nodes, EGFr was superior to ER in predicting relapse and survival (P less than .01 and P less than .005, respectively, compared to P less than .1 and P less than .1, log-rank). In a multivariate (Cox model) analysis, only EGFr--out of EGFr, ER, size, and grade--was predictive for either relapse-free or overall survival for patients with node-negative disease (P = .052 and P = .026, respectively). One hundred eighty-seven case patients in the series were assessed for neu expression immunochemically, and 31 were positive. There was a highly significant increased risk of relapse and death in the positive group. In patients with otherwise good prognostic markers (ER+, node-negative, well-differentiated tumors), neu expression predicted for significantly worsened overall survival.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Lateral orbitotomy--a review 总被引:2,自引:0,他引:2
Lateral orbitotomy is the standard surgical approach to lesions in the middle third of the orbit, to many lesions in the posterior third of the orbit and to benign lacrimal gland tumours. The indications, surgical technique and complications are discussed. 相似文献
47.
OBJECTIVES: to evaluate the Saville and Holdsworth Occupational Personality Questionnaire (OPQ) to assess its potential and validity as a tool in the recruitment of doctors. To determine the range of personality characteristics in a group of general practitioners. DESIGN: an administered commercially available questionnaire. SETTING: general practitioners in North and Mid. Stafftordshire. SUBJECTS: 133 general practitioners or trainees. RESULTS: 44% of general practitioners agreed to participate. The majority found it useful and recognised its potential to increase self-awareness, highlight weaknesses that might be improved and for future recruitment of others to their teams. Doctors' personality traits were similar to those of managerial/professional norms. The validity of the OPQ was supported by (a) significant associations with subjects' previously reported mental health problems and (b) 83% of respondents confirming that their reports correctly described their personalities at work. CONCLUSIONS: OPQs have a place in the recruitment of doctors by identifying appropriate people to strengthen the team. 相似文献
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Rolf Gronas B. Eng Peter G. Kalman MD Daryl S. Kucey MD Graham A. Wright PhD 《Journal of magnetic resonance imaging : JMRI》1997,7(4):637-643
Flow-independent angiography (FIA), an approach that isolates arterial blood using MR relaxation characteristics rather than flow effects, was evaluated for application in peripheral vascular disease (PVD). First, pilot studies were conducted in which FIA coronal projection images were obtained from controls and symptomatic patients with PVD to assess clinical utility. All control images corresponded to the expected leg arterial anatomy with little interference from deep veins (one of five) and muscle (zero of five). Superficial venous signal was less well suppressed in comparison to deep veins (four of five). Images of symptomatic patients were less consistent with difficulty suppressing muscle and deep venous signal in some cases and edema when present. We then compared T2 values for muscle (T2m, tibialis anterior), arterial blood (femoral and popliteal arteries), and venous blood (femoral, popliteal, and saphenous veins) in controls (n = 8) and symptomatic patients with intermittent claudication (n = 5) or ischemic rest pain (n = 7). Changes in T2 measurements of various tissues accounted for poorer contrast in symptomatic patients. Patients with ischemic rest pain had significantly higher T2m compared with controls (T2m = 39.3 ± 2.1 (1 standard error of the mean [SEM]) versus 30.9 ± .4, P < .01). For all measurements, other than saphenous vein, variances were greater in symptomatic patients. To realize the inherent advantages of FIA for this clinical application, additional work on suppression of signals from muscle, veins, and edema is required. One promising approach involves shifting from projection images to three-dimensional acquisitions for improved tissue suppression. 相似文献
50.
P. von Dadelszen Gynaecology Registrar M. D. G. Gillmer Consultant Gynaecologist M. D. Gray Consultant Gynaecologist H. P. McEwan Consultant Gynaecologist R. J. D. Pyper Consultant Gynaecologist T. P. Rollason Consultant Pathologist A. Wright Gynaecology Registrar 《BJOG : an international journal of obstetrics and gynaecology》1994,101(2):158-161