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51.
Ming Zhao Cheng Simon C F Rawlinson Andrew A Pitsillides Gul Zaman Subburaman Mohan David J Baylink Lance E Lanyon 《Journal of bone and mineral research》2002,17(4):593-602
The mechanism by which mechanical strain and estrogen stimulate bone cell proliferation was investigated using monolayer cultures of human osteoblastic TE85 cells and female human primary (first-passage) osteoblasts (fHOBs). Both cell types showed small but statistically significant dose-dependent increases in [3H]thymidine incorporation in response to 17beta-estradiol and to a single 10-minute period of uniaxial cyclic strain (1 Hz). In both cell types, the peak response to 17beta-estradiol occurred at 10(-8) - 10(-7) M and the peak response to strain occurred at 3500 microstrain ((mu)epsilon). Both strain-related and 17beta-estradiol-related increases in [3H]thymidine incorporation were abolished by the estrogen receptor (ER) modulator ICI 182,780 (10-8 M). Tamoxifen (10(-9) - 10(-8) M) increased [3H]thymidine incorporation in both cell types but had no effect on their response to strain. In TE85 cells, tamoxifen reduced the increase in [3H]thymidine incorporation associated with 17beta-estradiol to that of tamoxifen alone but had no such effect in fHOBs. In TE85 cells, strain increased medium concentrations of insulin-like growth factor (IGF) II but not IGF-I, whereas 17beta-estradiol increased medium concentrations of IGF-I but not IGF-II. Neutralizing monoclonal antibody (MNAb) to IGF-I (3 microg/ml) blocked the effects of 17beta-estradiol and exogenous truncated IGF-I (tIGF-I; 50 ng/ml) but not those of strain or tIGF-II (50 ng/ml). Neutralizing antibody to IGF-II (3 microg/ml) blocked the effects of strain and tIGF-II but not those of 17beta-estradiol or tIGF-I. MAb aIR-3 (100 ng/ml) to the IGF-I receptor blocked the effects on [3H]thymidine incorporation of strain, tIGF-II, 17beta-estradiol, and tIGF-I. HOBs and TE85 cells, act similarly to rat primary osteoblasts and ROS 17/2.8 cells in their dose-related proliferative responses to strain and 17beta-estradiol, both of which can be blocked by the ER modulator ICI 182,780. In TE85 cells (as in rat primaries and ROS 17/2.8 cells), the response to 17beta-estradiol is mediated by IGF-I, and the response to strain is mediated by IGF-II. Human cells differ from rat cells in that tamoxifen does not block their response to strain and reduces the response to 17beta-estradiol in TE85s but not primaries. In both human cell types (unlike rat cells) the effects of strain and IGF-II as well as estradiol and IGF-I can be blocked at the IGF-I receptor. 相似文献
52.
Although lesions of the pterygopalatine space are uncommon, there are instances in which this relatively inaccessible region must be entered for biopsy or excision of masses. Traditional open approaches to the pterygopalatine space, involving external or intraoral incisions, provide limited visualization and carry associated morbidities. The evolution and advancement of endoscopic sinus surgical technique in recent years has led to its application to anatomic areas outside the strict limits of the sinonasal cavities. Such minimally invasive approaches are safe, effective, and spare unnecessary discomfort to the patient. This article describes the authors' method for performing an endoscopic approach to the pterygopalatine space. 相似文献
53.
54.
Daniel P Potaczek Anetta Undas Magdalena Celinska-Lowenhoff Andrew Szczeklik 《Blood coagulation & fibrinolysis》2006,17(1):35-38
To evaluate whether the interleukin-6 (IL-6) -174 G/C polymorphism might alter the effects of micronized fenofibrate or simvastatin therapy on inflammatory markers, we measured IL-6, C-reactive protein, CD40 ligand, adhesion molecules, P-selectin and monocyte chemoattractant protein-1 in hypercholesterolemic patients both before and after a 30-day treatment. Serum IL-6 levels were significantly higher in patients with the GC or CC genotypes (P=0.04). The presence of the C allele was associated with greater absolute reduction of IL-6 levels (P=0.04) following fenofibrate treatment. There was no significant association between the -174 G/C IL-6 polymorphism and the effects of simvastatin treatment. A relationship between the -174 G/C IL-6 polymorphism and the anti-inflammatory action of fenofibrate reported might be useful in the optimization of the treatment regimen in patients receiving this class of drugs. 相似文献
55.
Andrew J Montgomery Kris Thielemans Mitul A Mehta Federico Turkheimer Sanida Mustafovic Paul M Grasby 《Journal of nuclear medicine》2006,47(12):1936-1944
Head movement presents a continuing problem in PET studies. Head restraint minimizes movement but is unreliable, resulting in the need to develop alternative strategies. These include frame-by-frame (FBF) realignment or use of motion tracking (MT) during the scan to realign PET acquisition data. Here we present a comparative analysis of these 2 methods of motion correction. METHODS: Eight volunteers were examined at rest using (11)C-raclopride PET with the radioligand administered as a bolus followed by constant infusion to achieve steady state. Binding potential (BP) was estimated using the ratio method during 2 periods of the scan at steady state. Head movement was compensated by using coregistration between frames (FBF) and 3 methods using MT measurements of head position acquired with a commercially available optical tracking system. RESULTS: All methods of realignment improved test-retest reliability and noise characteristics of the raw data, with important consequences for the power to detect small changes in radiotracer binding, and the potential to reduce false-positive and false-negative results. MT methods were superior to FBF realignment using coregistration on some indices. CONCLUSION: Such methods have considerable potential to improve the reliability of PET data with important implications for the numbers of volunteers required to test hypotheses. 相似文献
56.
57.
58.
Andrew Meikle Davison 《Forensic science, medicine, and pathology》2009,5(2):90-94
A 62-year-old male with no significant medical history developed thromboembolic complications in the lower limbs shortly after
an assault which involved punching and kicking to the trunk. Laparotomy revealed intra-abdominal injuries and an abdominal
aortic aneurysm. Death from multi-organ failure and sepsis occurred 9 days post-injury. The discussion concentrates on blunt
force trauma to the abdominal aorta, specifically on causation, mechanisms of injury and complications. 相似文献
59.
We followed all consecutive hip fracture patients admitted between 2004 and 2006, identified cases in which the intention was to treat non-operative and compared their functional outcome and mortality with a similar cohort treated surgically over the same period. We recorded length of hospital stay, place of discharge, pre and post-fracture mobility and residence, 30 days and 1 year mortality, re-admission due to same fracture and delayed surgery. The group treated surgically was recruited and matched for age, gender, pre and post-fracture mobility, mental confusion and independence. 25 patients were treated non-operative. 22 patients treated surgically over the same time period matched the patient characteristics of the non-operative arm. The mean hospital stay was 13 days in both groups. There were 4 extra-capsular fractures (3 displaced) and 21 intra-capsular fractures (5 displaced) in the non-operative arm and 11 extra-capsular fractures and 9 intra-capsular fractures in the surgically treated arm. 4 patients from the non-operative treatment group underwent late surgery because of persisting hip pain 20 days-2 months after the index event (2 cannulated screws, 1 hemiarthroplasty, 1 total hip arthroplasty). 11 patients in the surgical treatment arm underwent dynamic screw fixation, 1 had cannulated screw, 1 had total hip replacement and 7 had hemiarthroplasty. 14 of the non-operative treated patients were mobile independently or with aid before fracture but only 9 patients retained their pre-fracture mobility following treatment, compared to 16 patients pre-fracture and 11 patients post-fracture after surgery. 16 patients treated non-operative were living independently prior to injury but only 7 went back to their own residence. Of the operatively treated patients 14 patients were living independently and 10 patients went back to their previous residence. 1 month and 1 year mortality in the non-operative treated group was 4/21 and 7/21 respectively compared to 1/20 and 5/20 in the operative fixation group. There was no statistically significant difference in mobility, residence or mortality between the two groups (Fisher exact test, p > 0.05). Non-operative management after hip fracture is suitable for medically unfit patients and does not result in statistically significant difference in functional outcome or mortality compared to patients treated surgically. 相似文献
60.
Simon Bell Andrew J McLachlan Parisa Aslani Paula Whitehead Timothy F Chen 《Australia and New Zealand Health Policy》2005,2(1):29
The objective of this systematic review was to evaluate the impact of pharmacist delivered community-based services to optimise the use of medications for mental illness. Twenty-two controlled (randomised and non-randomised) studies of pharmacists' interventions in community and residential aged care settings identified in international scientific literature were included for review. Papers were assessed for study design, service recipient, country of origin, intervention type, number of participating pharmacists, methodological quality and outcome measurement. Three studies showed that pharmacists' medication counselling and treatment monitoring can improve adherence to antidepressant medications among those commencing treatment when calculated using an intention-to-treat analysis. Four trials demonstrated that pharmacist conducted medication reviews may reduce the number of potentially inappropriate medications prescribed to those at high risk of medication misadventure. The results of this review provide some evidence that pharmacists can contribute to optimising the use of medications for mental illness in the community setting. However, more well designed studies are needed to assess the impact of pharmacists as members of community mental health teams and as providers of comprehensive medicines information to people with schizophrenia and bipolar disorder 相似文献