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991.
Calcifications that lie within the skin of the breast may be mistakenly thought to be intraparenchymal on mammograms if they are projected over breast tissue in two views. A simple, reliable technique was developed to determine calcification location. It uses a commercially available stereotactic localization device and has been used successfully in six patients. 相似文献
992.
Glucocorticoids selectively inhibit the transcription of the interleukin 1 beta gene and decrease the stability of interleukin 1 beta mRNA 总被引:35,自引:6,他引:29 下载免费PDF全文
993.
Severe acute respiratory syndrome, or SARS, is a new infectious disease pandemic with important public health concerns. The high infectivity rate by means of droplet transmission places health care workers at substantial risk of contracting the disease. Radiology departments are particularly affected, since imaging plays a vital role in both diagnosis and follow-up of this disease. The authors outline their experience in infection control and isolation procedures during this outbreak. Barrier precautions, reconfiguration of the department, separation of imaging equipment, cleaning procedures, personal protective equipment, and staff safety are discussed. 相似文献
994.
995.
Prognostic index score and clinical prediction model of local regional recurrence after mastectomy in breast cancer patients 总被引:3,自引:0,他引:3
Cheng SH Horng CF Clarke JL Tsou MH Tsai SY Chen CM Jian JJ Liu MC West M Huang AT Prosnitz LR 《International journal of radiation oncology, biology, physics》2006,64(5):1401-1409
PURPOSE: To develop clinical prediction models for local regional recurrence (LRR) of breast carcinoma after mastectomy that will be superior to the conventional measures of tumor size and nodal status. METHODS AND MATERIALS: Clinical information from 1,010 invasive breast cancer patients who had primary modified radical mastectomy formed the database of the training and testing of clinical prognostic and prediction models of LRR. Cox proportional hazards analysis and Bayesian tree analysis were the core methodologies from which these models were built. To generate a prognostic index model, 15 clinical variables were examined for their impact on LRR. Patients were stratified by lymph node involvement (<4 vs. >or =4) and local regional status (recurrent vs. control) and then, within strata, randomly split into training and test data sets of equal size. To establish prediction tree models, 255 patients were selected by the criteria of having had LRR (53 patients) or no evidence of LRR without postmastectomy radiotherapy (PMRT) (202 patients). RESULTS: With these models, patients can be divided into low-, intermediate-, and high-risk groups on the basis of axillary nodal status, estrogen receptor status, lymphovascular invasion, and age at diagnosis. In the low-risk group, there is no influence of PMRT on either LRR or survival. For intermediate-risk patients, PMRT improves LR control but not metastases-free or overall survival. For the high-risk patients, however, PMRT improves both LR control and metastasis-free and overall survival. CONCLUSION: The prognostic score and predictive index are useful methods to estimate the risk of LRR in breast cancer patients after mastectomy and for estimating the potential benefits of PMRT. These models provide additional information criteria for selection of patients for PMRT, compared with the traditional selection criteria of nodal status and tumor size. 相似文献
996.
Epidemiological studies have demonstrated a high association of inorganic arsenic exposure with vascular disease. Our recent in vitro studies have linked this vascular damage to vascular endothelial dysfunction induced by arsenic exposure. However, cell-cycle arrest induced by arsenic and its involvement in vascular dysfunction remain to be clarified. In this study, we employed primary porcine aortic endothelial cells to investigate regulatory mechanisms of G2/M phase arrest induced by arsenite. Our study revealed that lower concentrations of arsenite (1 and 3 μM) increased cell proliferation, whereas higher concentrations of arsenite (10, 20, and 30 μM) inhibited cell proliferation together with correlated increases in G2/M phase arrest. We found that this arsenite-induced G2/M phase arrest was accompanied by accumulation and/or phosphorylation of checkpoint-related molecules, including p53, Cdc25B, Cdc25C, and securin. Inhibition of activations of these checkpoint-related molecules by caffeine significantly attenuated the 30-μM arsenite-induced G2/M phase arrest by 93%. Our data suggest that the DNA damage responsive kinases ATM (ataxia-telangiectasia mutated) and ATR (ATM and Rad3-related) play critical roles in arsenite-induced G2/M phase arrest in aortic endothelial cells possibly via regulation of checkpoint-related signaling molecules including p53, Cdc25B, Cdc25C, and securin. 相似文献
997.
Friesen RW Ducharme Y Ball RG Blouin M Boulet L Côté B Frenette R Girard M Guay D Huang Z Jones TR Laliberté F Lynch JJ Mancini J Martins E Masson P Muise E Pon DJ Siegl PK Styhler A Tsou NN Turner MJ Young RN Girard Y 《Journal of medicinal chemistry》2003,46(12):2413-2426
A SAR study on the tertiary alcohol series of phosphodiesterase-4 (PDE4) inhibitors related to 1 is described. In addition to inhibitory potency against PDE4 and the lipopolysaccharide-induced production of TNFalpha in human whole blood, the binding affinity of these compounds for the human ether-a-go-go related gene (hERG) potassium channel (an in vitro measure for the potential to cause QTc prolongation) was assessed. Four key structural moieties in the molecule were studied, and the impact of the resulting modifications in modulating these activities was evaluated. From these studies, (+)-3d (L-869,298) was identified as an optimized structure with respect to PDE4 inhibitory potency, lack of binding affinity to the hERG potassium channel, and pharmacokinetic behavior. (+)-3d exhibited good in vivo efficacy in several models of pulmonary function with a wide therapeutic index with respect to emesis and prolongation of the QTc interval. 相似文献
998.
Holl RW Swift PG Mortensen HB Lynggaard H Hougaard P Aanstoot HJ Chiarelli F Daneman D Danne T Dorchy H Garandeau P Greene S Hoey HM Kaprio EA Kocova M Martul P Matsuura N Robertson KJ Schoenle EJ Sovik O Tsou RM Vanelli M Aman J 《European journal of pediatrics》2003,162(1):22-29
The optimal insulin regimen for paediatric patients with type 1 diabetes remains controversial. Therefore this multicentre study was performed in adolescents over a 3-year period to assess metabolic control, severe hypoglycaemia, and weight gain in relation to insulin injection regimens. Out of 2873 children and adolescents in an international survey in 1995, 872 adolescents (433 boys, 439 girls, mean age in 1995 11.3+/-2.2 years) were restudied in 1998, relating insulin regimens to HbA(1c) measured in a central laboratory. In addition, the daily dose of insulin, changes in body mass index (BMI), and events of severe hypoglycaemia were evaluated. Over 3 years, the use of multiple injection regimens increased from 42% to 71%: 251 patients remained on twice daily insulin, 365 remained on multiple injections and 256 shifted from twice daily insulin to multiple injections. In all three subgroups an increase in insulin dose, a deterioration of metabolic control, and an increase in BMI were observed. Metabolic control deteriorated less than expected over 3 years during adolescence (HbA(1c) 1995: 8.7+/-1.6%; 1998 observed: 8.9+/-1.6%, HbA(1c) expected for 1998: 9.0%). BMI increased more than expected, the increase was greatest in patients switching from twice daily to multiple injections, and higher in females compared to males. CONCLUSION: in this international study, metabolic control was unsatisfactory in many adolescents with type 1 diabetes irrespective of the insulin regimen. No improvement in metabolic control was observed in this cross-sectional survey, over 3 years in any of the subgroups. Even the group switching from twice to multiple injections did not improve blood glucose control and the increase in body mass index was most pronounced in this group. Conclusive evidence, however, should be based on prospectively planned, randomised therapeutic trials in paediatric patients. 相似文献
999.
BACKGROUND: Superior vena cava syndrome (SVCS) is an unusual condition resulting from upper body venous congestion. Little has been written about this condition and pregnancy. CASE: Despite concerns about cardiopulmonary decompensation from the hemodynamic changes of pregnancy, gestation proceeded uneventfully in a woman with SVCS. CONCLUSION: Pregnancy can be well tolerated in patients with SVCS. 相似文献
1000.
Bleeding marginal ulcers: angiographic evaluation 总被引:2,自引:0,他引:2