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91.
92.
Ian R. Falconer Michael D. Burch Dennis A. Steffensen Mandy Choice O. Robert Coverdale 《Environmental toxicology》1994,9(2):131-139
Hepatotoxins from blue-green algae are increasingly recognized as a potential hazard in drinking water supplies. The clinical consequences of ingestion include acute or chronic liver injury, with the possibility of enhanced susceptibility to, and growth of, liver tumors. To establish guidelines for water safety requires the demonstration of dose-dependent effects of toxicity and experimental determination of maximum “no-adverse-effect levels.” This paper describes the use of growing pigs as a model for human injury resulting from Microcystis toxins in drinking water. Risk assessment calculations using a series of safety factors are carried out, resulting in a guideline level after incorporating an additional safety factor for tumor promotion of approximately 1.0 μg toxins/L. With the Microcystis used for this trial, that concentration corresponds to 5000 cells/mL. © 1994 by John Wiley & Sons, Inc.. 相似文献
93.
Joseph V. Hajnal Ralph Myers Angela Oatridge Jane E. Schwieso Ian R. Young Graeme M. Bydder 《Magnetic resonance in medicine》1994,31(3):283-291
To assess the effect of stimulus correlated motion on the appearance of functional magnetic resonance images, conventional visual and motor protocols were each performed by four normal volunteers and an image co-registration technique was used to retrospectively monitor subject motion. In three studies synthetic data sets were constructed from single baseline images using the positional information obtained from the co-registration procedure. Cumulative difference images were then created from both the synthetic and functional image sets. Stimulus correlated motion was detected in all eight studies and the synthetic cumulative difference images showed striking similarities to the equivalent functional images in each case. 相似文献
94.
95.
Nina Rieckmann William Gerin Ian M Kronish Matthew M Burg William F Chaplin Grace Kong Fran?ois Lespérance Karina W Davidson 《Journal of the American College of Cardiology》2006,48(11):2218-2222
OBJECTIVES: We tested whether improvements in depressive symptoms precede improved adherence to aspirin in patients with acute coronary syndromes (ACS). BACKGROUND: Depression is associated with medication nonadherence in patients with ACS, but it is unclear whether changes in depression impact on adherence. METHODS: Electronic medication monitoring was used to measure adherence to aspirin during a 3-month period in a consecutive cohort of 172 patients (25 to 85 years) recruited within 1 week of hospitalization for ACS. Depressive symptom severity was assessed using the Beck Depression Inventory (BDI) during hospitalization and at 1 and 3 months after hospitalization. Adherence was defined as the percentage of days aspirin was taken as prescribed. RESULTS: Depression severity in hospital was associated with nonadherence in a gradient fashion: 15% of non-depressed patients (BDI score 0 to 4), 29% of mildly depressed patients (BDI score 10 to 16), and 37% of patients with moderately-to-severely depressive symptoms (BDI score >16) took aspirin less than 80% of the time (p = 0.03). A cross-lagged path analytic model revealed that improvements in depressive symptoms in the first month after the ACS were associated with improvements in adherence rates in the subsequent 2 months (standardized direct effect -0.32, p = 0.016). CONCLUSIONS: Diagnosis and treatment of depressive symptoms may improve medication adherence in patients after ACS. 相似文献
96.
97.
Fusion of the metarcarpophalangeal joint of the thumb is an accepted treatment in the management of instability or osteoarthritis following trauma to this joint. A review was made of the literature and 30 of the senior author's (RH) patients who had had this operation, in order to determine what effect the operation had on the pain in their thumb, any symptoms of instability, interference with work and daily activities, and strength in the hand. All of the patients achieved bony union and the average angle of fusion was 7.6 degrees of flexion. All of the patients were either satisfied or very satisfied with the results of the operation, and had an average increase of 6.3 points on a 12 point rating scale. However, 48% of patients had some mild intermittent pain and 43% complained of some difficulty with fine motor tasks. Twelve patients were able to attend for formal evaluation including the Jebson and Crawford Hand Function Tests which revealed some decrease in hand function in all of those tested. It was concluded that this method of arthrodesis of the metacarpophalangeal joint of the thumb gives reliable results, with high patient acceptance, but does not result in an entirely normal thumb or hand function. 相似文献
98.
Our experience with the free vascularized fascial flap based on the radial artery used for intraoral reconstruction is described. Thirteen patients underwent primary or secondary reconstruction following major resections for malignant disease. The osseofascial flap incorporating radial bone proved to be ideal when reconstruction of composite mandibular or maxillary defects was undertaken. The flaps rapidly underwent surface epithelialization, and submucosal fibrosis provided the ideal attached mucosal lining for prosthetic rehabilitation. © 1994 John Wiley & Sons, Inc. 相似文献
99.
Lara Kevorkian David A. Young Clare Darrah Simon T. Donell Lee Shepstone Sarah Porter Sarah Brockbank Dylan R. Edwards rew E. Parker Ian M. Clark 《International journal of experimental pathology》2004,85(1):A23-A23
Objective To profile the expression of all known members of the matrix metalloproteinase ( MMP ), a disintegrin and metalloproteinase with thrombospondin motifs ( ADAMTS ), and tissue inhibitor of metalloproteinases ( TIMP s) gene families in normal cartilage and that from patients with osteoarthritis (OA).
Methods Human cartilage was obtained from femoral heads at joint replacement for either osteoarthritis or following fracture to the neck of femur. Total RNA was purified and expression of genes assayed using quantitative real-time PCR.
Results Several members of the above gene families were regulated in OA. Genes increasing in expression in OA were: at P < 0.001, MMP-13 , MMP-28 , ADAMTS-16 ; at P < 0.01, MMP-9 , MMP-16 , ADAMTS-2 , ADAMTS-14 and at P < 0.05, MMP-2 , TIMP-3 , ADAMTS-12 . Genes decreasing in expression in OA were: at P < 0.001, MMP-1 , MMP-3 , ADAMTS-1 ; at P < 0.01, MMP-10 , TIMP-1 , ADAMTS-9 and at P < 0.05, TIMP-4 , ADAMTS-5 , ADAMTS-15 . Correlation analysis revealed that groups of genes across the gene families are co-expressed in cartilage.
Conclusion This is the first comprehensive expression profile of all known MMP , ADAMTS and TIMP genes in cartilage. Patterns of expression provide a foundation on which to understand mechanisms of gene regulation in OA and potentially for refining the specificity of anti-proteolytic therapies. 相似文献
Methods Human cartilage was obtained from femoral heads at joint replacement for either osteoarthritis or following fracture to the neck of femur. Total RNA was purified and expression of genes assayed using quantitative real-time PCR.
Results Several members of the above gene families were regulated in OA. Genes increasing in expression in OA were: at P < 0.001, MMP-13 , MMP-28 , ADAMTS-16 ; at P < 0.01, MMP-9 , MMP-16 , ADAMTS-2 , ADAMTS-14 and at P < 0.05, MMP-2 , TIMP-3 , ADAMTS-12 . Genes decreasing in expression in OA were: at P < 0.001, MMP-1 , MMP-3 , ADAMTS-1 ; at P < 0.01, MMP-10 , TIMP-1 , ADAMTS-9 and at P < 0.05, TIMP-4 , ADAMTS-5 , ADAMTS-15 . Correlation analysis revealed that groups of genes across the gene families are co-expressed in cartilage.
Conclusion This is the first comprehensive expression profile of all known MMP , ADAMTS and TIMP genes in cartilage. Patterns of expression provide a foundation on which to understand mechanisms of gene regulation in OA and potentially for refining the specificity of anti-proteolytic therapies. 相似文献
100.