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排序方式: 共有318条查询结果,搜索用时 15 毫秒
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David M. Holmes Apatsa Matatiyo Atupele Mpasa Minke H. W. Huibers Geoffrey Manda Tamiwe Tomoka Maurice Mulenga Ruth Namazzi Parth Mehta Mark Zobeck Rizine Mzikamanda Murali Chintagumpala Carl Allen Jed G. Nuchtern Eric Borgstein Daniel C. Aronson Nmazuo Ozuah Bip Nandi Casey L. McAtee 《Pediatric blood & cancer》2023,70(5):e30242
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Manda E. Gent Patrick Crowley J. Richard Ludwig Rashida Anwar David A. Sugden Paul F. G. Sims Stephen G. Oliver 《Current genetics》1985,10(1):29-33
Summary We describe the construction of a cosmid cloning vector, pMT555, which allows positive selection for the presence of an inserted DNA fragment. The vector contains sequences which enable its replication and selection in either E. coli or Saccharomyces cerevisiae. We demonstrate that pMT555 may be used for the efficient construction of total genomic banks from small quantities of donor DNA. The positive selection permits the stable maintenance of the cosmid in E. coli and the faithful replication of inserted sequences. 相似文献
74.
Ðeni Smilović Radojčić Manda Švabić Kolacio Milan Radojčić David Rajlić Božidar Casar Dario Faj Slaven Jurković 《Medical Dosimetry》2018,43(4):363-369
Advanced dose calculation algorithms for radiation therapy treatment planning can report external beam photon dose 2-sided, in terms of dose-to-medium (Dm) and dose-to-water (Dw). The purpose of our study was to determinate the effect of Dw and Dm reporting modes built in Elekta Monaco treatment planning system on intensity-modulated radiotherapy dose distributions for patients with nasopharyngeal cancer. For 13 patients involved in this retrospective study, 2 plans were created: 1 using Dw and another according to Dm reporting mode. Treatment plans were normalized such that 100% planning target volume should be covered by 95% of prescribed dose. Dose-volume constraints were assigned according to international standards. The comparison between dose distributions was performed evaluating quantities important for respective volumes of interest. For target volumes, heterogeneity index and conformity index methodology were used along with the maximum dose concept. Also, for the comparisons over particular organ at risk, maximum dose or mean dose as well as dose-volume concepts were used. For all target volumes and majority of organs at risk, the differences between 2 reporting modes are statistically insignificant, but this is not the case for bony structured organs at risks: mandible and cochlea. It was observed that Dw is higher than Dm with mean difference of 9.91% (p?=?0.000009) of the mandible volume covered with 70?Gy. The same trend was observed for left and right cochlea with difference in mean dose of 8.74% (p?=?0.037) and 6.87% (p?=?0.029), respectively. The comparative analysis of dosimetric parameters in this study shows that the selection of reporting modes in Monaco treatment planning system can produce dose differences up to 15% in high-density volumes such as mandible and cochlea, which might have clinical consequences. 相似文献
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Abstract: Cerebellum is a vital organ responsible for the motor coordination and recently it has been reported to be involved in cognitive function. Reactive oxygen species are implicated in neurodegeneration and cognitive disorders because of higher vulnerability of neuronal tissues. Therefore, the present study aimed at investigating the role of melatonin against high-LET (linear energy transfer) 56 Fe particle irradiation-induced oxidative damage and apoptosis in the mouse cerebellum. Radiation-induced oxidative damage was examined using a neuronal-specific terminal deoxynucleotidyl transferase-mediated nick end-labeling (TUNEL), quantitative histopathology, DNA damage (comet assay), carbonyl content and 4-HAE + MDA (4-hydroxyalkenal + malondialdehyde) status of the cerebellum. Radiation exposure augmented the number of TUNEL positive cell, DNA migration in the comet tail and carbonyl and 4-HAE + MDA level in the cerebellum. Melatonin pretreatment significantly inhibited the oxidative damage to biomolecules as well as cerebellar apoptosis. Melatonin-treated irradiated mice showed higher counts of intact Purkinje cells as compared to vehicle-treated irradiated mice. In addition, radiation induced augmentation of 8-hydroxy-2'-deoxyguanosine (8-OHdG) and a decline in the total antioxidant capacity in serum; these changes were also ameliorated by melatonin pretreatment. The present results provide evidence supporting the antioxidant and neuroprotective function of melatonin. 相似文献
79.
Relationship between corrected TIMI frame counts at three weeks and late survival after myocardial infarction 总被引:5,自引:0,他引:5
French JK Hyde TA Straznicky IT Andrews J Lund M Amos DJ Zambanini A Ellis CJ Webber BJ McLaughlin SC Whitlock RM Manda SO Patel H White HD 《Journal of the American College of Cardiology》2000,35(6):1516-1524
OBJECTIVES: To evaluate the corrected Thrombolysis in Myocardial Infarction (TIMI) frame count (CTFC) as a predictor of late survival after myocardial infarction. BACKGROUND: Thrombolysis in Myocardial Infarction flow grades predict late survival after myocardial infarction. The CTFC provides a more reproducible measurement of infarct-related artery blood flow than the TIMI flow grade, and has been linked to 30-day outcomes, but it has not yet been established how the CTFC correlates with late survival. METHODS: Of 1,001 patients with acute myocardial infarction presenting within 4 h of symptom onset, 882 underwent angiography at approximately three weeks. Infarct artery flow was assessed, blinded to clinical outcomes, according to the CTFC and TIMI flow grade. Late cardiac mortality and survival were determined in 97.5% of patients. RESULTS: The mean CTFC was 40 +/- 29 in 644 patent infarct arteries (median, 34 [interquartile range, 24 to 47]). The CTFC, assessed as a continuous univariate variable, was found to be a predictor of five-year survival, as was the TIMI flow grade (both p < 0.001). On multivariate analysis, factors associated with five-year survival included the ejection fraction or end-systolic volume index (both p < 0.001); exercise duration (p = 0.005), age (p = 0.008), diabetes (p = 0.02) and CTFC (p = 0.02) or TIMI flow (p = 0.02). The same factors, except for the CTFC and TIMI flow grade, were predictors of 10-year survival. CONCLUSIONS: The CTFC three weeks after myocardial infarction was an independent predictor of five-year survival, but not 10-year survival. Although the CTFC provided additional prognostic information within TIMI flow grades, its superiority was not demonstrated. 相似文献
80.
Corrected TIMI frame counts correlate with stenosis severity and infarct zone wall motion after thrombolytic therapy 总被引:1,自引:0,他引:1
Amos DJ French JK Andrews J Ashton NG Williams BF Whitlock RM Manda SO White HD 《American heart journal》2001,141(4):586-591
BACKGROUND: The majority of patients with patent infarct-related arteries after thrombolytic therapy have slower than normal flow, which relates to myocardial perfusion. METHODS: To evaluate the relationships between blood levels of creatine kinase (CK) and the corrected Thrombolysis in Myocardial Infarction (TIMI) frame count (CTFC), infarct artery stenosis, and left ventricular function, we studied 397 patients with a first myocardial infarction who underwent angiography at 3 weeks. TIMI flow grades, the CTFC, infarct artery stenosis, and infarct zone wall motion (by contrast ventriculography using the centerline method) were assessed, and CK levels (in units per liter) were measured hourly for the first 4 hours after streptokinase (1.5 x 10(6) U over 30-60 minutes) and then every 4 hours over the next 20 hours, all blinded to treatment and outcome. RESULTS: Infarct artery stenosis and the CTFC, assessed as continuous variables, correlated in patients with patent infarct arteries (r = 0.33, P <.001). Also, there was a significant correlation between the CTFC and the sum of hypokinetic chords in the infarct zone (r = 0.15, P =.01). Patients with total occlusion or markedly slowed infarct artery flow (CTFC >100) had a higher fraction of chords with wall motion >2 SDs below normal (0.65 [0.41, 0.80] vs 0.37 [0.0, 0.67]) compared with patients with normal flow (CTFC < or =27) (P <.001). The rates of increase of median CK levels with respect to TIMI flow grades were 342 U/L/h for TIMI 3 versus 212 U/L/h for TIMI 2 versus 140 U/L/h for TIMI 0-1 (P <.0001). CONCLUSIONS: Prolonged corrected TIMI frame counts correlate with stenosis severity in the infarct artery after infarction, infarct zone regional wall motion, and CK levels. 相似文献