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861.
Ali HR Dawson SJ Blows FM Provenzano E Leung S Nielsen T Pharoah PD Caldas C 《The Journal of pathology》2012,226(1):97-107
There is an urgent need to improve prognostic classifiers in breast cancer. Ki67 and B-cell lymphoma 2 protein (BCL2) are established prognostic markers which have traditionally been assessed separately, in a dichotomous manner. This study was conducted to test the hypothesis that combinatorial assessment of these markers would provide superior prognostic information and improve their clinical utility. Tissue microarrays were used to assess the expression of Ki67 and BCL2 in 2749 cases of invasive breast cancer. We devised a Ki67/BCL2 index representing the relative expression of each protein and assessed its association with breast cancer-specific survival (BCSS) using a Cox proportional-hazards model. Based on our findings, an independent cohort of 3992 cases was used to validate the prognostic significance of the Ki67/BCL2 index. All survival analyses were conducted on complete data as well as data where missing values were resolved using multiple imputation. This study complied with reporting recommendations for tumour marker prognostic studies (REMARK) criteria. The Ki67/BCL2 index showed a significant association with BCSS at 10 years in estrogen receptor (ER)-positive disease. In multivariate analysis, adjusting for major clinical and molecular markers, the Ki67/BCL2 index retained prognostic significance, robustly classifying cases into three risk groups [intermediate- versus low-risk hazard ratio (HR), 1.5; 95% confidence interval (95% CI), 1.0-2.0; p = 0.031; high- versus low-risk HR, 2.6; 95% CI, 1.3-5.0; p = 0.005]. This finding was validated in an independent cohort of 3992 tumours containing 2761 ER-positive tumours (intermediate- versus low-risk HR, 1.7; 95% CI, 1.3-2.1; p < 0.001; high- versus low-risk HR, 2.0; 95% CI, 1.4-2.9; p < 0.001). Ki67 and BCL2 can be effectively combined to produce an index which is an independent predictor of BCSS in ER-positive breast cancer, enhancing their potential prognostic utility. 相似文献
862.
863.
The primary mechanism underlying antagonism among microorganisms is the production of antagonistic substances called antibiotics that inhibit the growth of pathogens. In this study, the antagonistic substances produced by the Bacillus amyloliquefaciens strain NJN‐6 that had antifungal activity against Fusarium oxysporum were extracted and identified. The active antifungal substance was extracted from dried leavening with ultrasound‐assisted extraction (UAE), using n ‐butanol as the extractant. HPLC/ESI‐MS was performed to investigate the components of the extracts. The results of the study showed that the antimicrobial substances consisted of three homologues of the iturin A family with molecular weights of 1043, 1057 and 1071 Da and of two homologues of the fengycin family with molecular weights of 1477 and 1491 Da. The effects of ultrasonic treatment time, extraction time and extractant volume, three major methodological parameters, were also studied to determine the optimal conditions for extraction. Compared with traditional extraction techniques, UAE is a simple, cheap and environmentally friendly method that represents a new option for the isolation and identification of lipopeptides and other active compounds. These antifungal substances extracted and identified from Bacillus amyloliquefaciens NJN‐6 will help us to understand its biocontrol mechanism against Fusarium oxysporum. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
864.
865.
Qayum M Nisar M Shah MR Adhikari A Kaleem WA Khan I Khan N Gul F Khan IA Zia-Ul-Haq M Khan A 《Phytotherapy research : PTR》2012,26(4):552-556
A study was conducted to identify constituents that might be responsible for analgesic and antiinflammatory conditions. Tasumatrol B, 1,13-diacetyl-10-deacetylbaccatin III (10-DAD) and 4-deacetylbaccatin III (4-DAB) were isolated from the bark extract of Taxus wallichiana Zucc. All the compounds were assessed for analgesic and antiinflammatory activities using an acetic acid-induced writhing model, a hot-plate test, a carrageenan-induced paw oedema model, a cotton-pellet oedema model and in vitro lipoxygenase inhibitory assay. All the compounds, especially tasumatrol B, revealed significant analgesic activity in comparison to a saline group based on an acetic acid-induced model. Similarly all of the test compounds, particularly tasumatrol B, showed significant antiinflammatory activity. However, all the compounds failed to exhibit any considerable activity in of the hot-plate test and the in vitro lipoxygenase inhibitory assay. This study has highlighted the potential of tasumatrol B to be further explored as a new lead compound for the management of pain and inflammation, one that has been discovered by scientific validation of the traditional medicinal use of T. wallichiana Zucc. 相似文献
866.
Benson AB Arnoletti JP Bekaii-Saab T Chan E Chen YJ Choti MA Cooper HS Dilawari RA Engstrom PF Enzinger PC Fakih MG Fleshman JW Fuchs CS Grem JL Leong LA Lin E May KS Mulcahy MF Murphy K Rohren E Ryan DP Saltz L Sharma S Shibata D Skibber JM Small W Sofocleous CT Venook AP Willett C Freedman-Cass DA;National Comprehensive Cancer Network 《Journal of the National Comprehensive Cancer Network : JNCCN》2012,10(4):449-454
The workup and management of squamous cell anal carcinoma, which represents the most common histologic form of the disease, are addressed in the NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Anal Carcinoma. These NCCN Guidelines Insights provide a summary of major discussion points of the 2012 NCCN Anal Carcinoma Panel meeting. In summary, the panel made 4 significant changes to the 2012 NCCN Guidelines for Anal Carcinoma: 1) local radiation therapy was added as an option for the treatment of patients with metastatic disease; 2) multifield technique is now preferred over anteroposterior-posteroanterior (AP-PA) technique for radiation delivery and the AP-PA technique is no longer recommended as the standard of care; 3) PET/CT should now be considered for radiation therapy planning; and 4) a section on risk reduction was added to the discussion section. In addition, the panel discussed the use of PET/CT for the workup of anal canal cancer and decided to maintain the recommendation that it can be considered in this setting. They also discussed the use of PET/CT for the workup of anal margin cancer and for the assessment of treatment response. They reaffirmed their recommendation that PET/CT is not appropriate in these settings. 相似文献
867.
A Mehdi S A Bokhari N Yousuf A Umerani S Chughtai F Hussain A Raza 《Anticancer research》1992,12(5):1443-1446
HL-60 cells were sequentially labeled with the thymidine analogues iododeoxyuridine (IUdR) and bromodeoxyuridine (BrdU). The labeling index (LI), the duration of S-phase (Ts) and the total cell cycle time (Tc) were measured immediately. It was therefore possible to predict the next time when the single versus double labeled cells would re-enter the S-phase. In our study, the Tc was calculated to be 20 hours. The third label, tritiated thymidine (3HTdR), was introduced at the predicted time of 20 hours to confirm the validity of the previously calculated Tc. The actual percentage of cells which were labeled by (3HTdR) was very similar to the predicted value. We conclude, therefore, that the calculated cell cycle time correlated well with the actual cell cycle time, at least in a controlled in vitro culture system. This novel triple label method validates our double-label technique developed for cell cycle measurements. 相似文献
868.
Ahmed Ehsanur Rahman Md Moinuddin Mitike Molla Alemayehu Worku Lisa Hurt Betty Kirkwood Sanjana Brahmawar Mohan Sarmila Mazumder Zulfiqar Bhutta Farrukh Raza Sigilbert Mrema Honorati Masanja Daniel Kadobera Peter Waiswa Rajiv Bahl Mike Zangenberg Lulu Muhe 《Bulletin of the World Health Organization》2014,92(9):664-671
Objective
To investigate the clinical characteristics of children who died from diarrhoea in low- and middle-income countries, such as the duration of diarrhoea, comorbid conditions, care-seeking behaviour and oral rehydration therapy use.Methods
The study included verbal autopsy data on children who died from diarrhoea between 2000 and 2012 at seven sites in Bangladesh, Ethiopia, Ghana, India, Pakistan, Uganda and the United Republic of Tanzania, respectively. Data came from demographic surveillance sites, randomized trials and an extended Demographic and Health Survey. The type of diarrhoea was classified as acute watery, acute bloody or persistent and risk factors were identified. Deaths in children aged 1 to 11 months and 1 to 4 years were analysed separately.Findings
The proportion of childhood deaths due to diarrhoea varied considerably across the seven sites from less than 3% to 30%. Among children aged 1–4 years, acute watery diarrhoea accounted for 31–69% of diarrhoeal deaths, acute bloody diarrhoea for 12–28%, and persistent diarrhoea for 12–56%. Among infants aged 1–11 months, persistent diarrhoea accounted for over 30% of diarrhoeal deaths in Ethiopia, India, Pakistan, Uganda and the United Republic of Tanzania. At most sites, more than 40% of children who died from persistent diarrhoea were malnourished.Conclusion
Persistent diarrhoea remains an important cause of diarrhoeal death in young children in low- and middle-income countries. Research is needed on the public health burden of persistent diarrhoea and current treatment practices to understand why children are still dying from the condition. 相似文献869.
Background
A true gold standard to rule out a significant cervical spine injury in subset of blunt trauma patients with altered sensorium is still to be agreed upon. The objective of this study is to determine whether in obtunded adult patients with blunt trauma, a clinically significant injury to the cervical spine be ruled out on the basis of a normal multidetector cervical spine computed tomography.Methods
Comprehensive database search was conducted to include all the prospective and retrospective studies on blunt trauma patients with altered sensorium undergoing cervical spine multidetector CT scan as core imaging modality to “clear” the cervical spine. The studies used two main gold standards, magnetic resonance imaging of the cervical spine and/or prolonged clinical follow-up. The data was extracted to report true positive, true negatives, false positives and false negatives. Meta-analysis of sensitivity, specificity, negative and positive predictive values was performed using Meta Analyst Beta 3.13 software.We also performed a retrospective investigation comparing a robust clinical follow-up and/or cervical spine MR findings in 53 obtunded blunt trauma patients, who previously had undergone a normal multidetector CT scan of the cervical spine reported by a radiologist.Results
A total of 10 studies involving 1850 obtunded blunt trauma patients with initial cervical spine CT scan reported as normal were included in the final meta-analysis. The cumulative negative predictive value and specificity of cervical spine CT of the ten studies was 99.7% (99.4–99.9%, 95% confidence interval). The positive predictive value and sensitivity was 93.7% (84.0–97.7%, 95% confidence interval).In the retrospective review of our obtunded blunt trauma patients, none was later diagnosed to have significant cervical spine injury that required a change in clinical management.Conclusion
In a blunt trauma patient with altered sensorium, a normal cervical spine CT scan is conclusive to safely rule out a clinically significant cervical spine injury. The results of this meta-analysis strongly support the removal of cervical precautions in obtunded blunt trauma patient after normal cervical spine computed tomography. Any further imaging like magnetic resonance imaging of the cervical spine should be performed on case-to-case basis. 相似文献870.
Ischemic heart disease is the leading cause of death in the developed countries for those older than 65 years of age. In patients suspected to have coronary artery disease a stress test should be performed to identify the vulnerability of the myocardium to ischemia. As a rule of thumb, the evaluation of coronary artery disease is best done by exercise stress test. In patients who are not able to exercise adequately, pharmacological stress agents are used. The commonly used agents are the coronary vasodilators, adenosine and dipyridamole and the catecholamines, dobutamine and arbutamine. These agents are combined with imaging techniques to increase the sensitivity and specificity of the test. These agents have been widely used and have an excellent safety profile. Another advantage in using pharmacological stress agents is that they do not affect the image quality, especially with echocardiography and magnetic resonance imaging. Ongoing developments hold promise for safer and more reliable pharmacological stress agents in the future. 相似文献