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951.
Heye T Stein D Antolovic D Dueck M Kauczor HU Hosch W 《Journal of magnetic resonance imaging : JMRI》2012,35(4):859-867
Purpose:
To investigate the diagnostic performance of a cine magnetic resonance imaging (MRI) sequence in the visualization and detection of impaired bowel peristalsis.Materials and Methods:
In all, 91 consecutive patients (mean age 45 years) were prospectively examined on a 1.5 T system and stratified into a surgery group (n = 22) and a nonsurgery group (n = 69). A coronal fast imaging with steady‐state precession (TrueFISP) sequence with 30 acquisitions per slice covered the abdomen in 10–15 slices each 7–12 mm thick (temporal resolution: 6–8 sec per frame). Image evaluation for reduced bowel peristalsis and relevant bowel stenosis was compared to surgical findings or clinical follow‐up.Results:
Cine MRI reached 96% accuracy (94% sensitivity; 100% specificity) in detecting a relevant reduction in bowel peristalsis and 85% of relevant stenosis was identified in the surgery group. Twenty of 69 patients of the nonsurgery group showed reduced peristalsis on cine MR which was attributed to underlying disease; 49/69 patients in this group had no findings on cine MR and were uneventfully followed up.Conclusion:
Cine MRI of the bowel provides functional information of bowel passage. The visualization of a reduction in peristalsis may improve the assessment of the functional impact of suspected bowel adhesions or stenosis. Standard bowel MR protocols can be easily complemented by cine MR, extending scan time by <4 minutes. J. Magn. Reson. Imaging 2012;35:859–867. © 2012 Wiley Periodicals, Inc. 相似文献952.
This paper presents the synthesis of a coumarin derivative of resorcin[4]arene (1) using a cascade thermolysis/Michael reaction. The influence of the hydrogen bonding system on the conformational rigidity and cyclochirality of the coumarin derivative of resorcin[4]arene was discussed; these properties depended on the proton-donor–acceptor properties of the solvent. Significant differences, which depended on the environment, in the coumarin derivative of resorcin[4]arene fluorescence were observed and discussed.This paper presents the synthesis of a coumarin derivative of resorcin[4]arene (1) using a cascade thermolysis/Michael reaction. 相似文献
953.
954.
Robert D. McBane Waldemar E. Wysokinski Jennifer G. Le‐Rademacher Tyler Zemla Aneel Ashrani Alfonso Tafur Usha Perepu Daniel Anderson Krishna Gundabolu Charles Kuzma Juliana Perez Botero Roberto A. Leon Ferre Stanislav Henkin Charles J. Lenz Damon E. Houghton Prakash Vishnu Charles L. Loprinzi 《Journal of thrombosis and haemostasis》2020,18(2):411-421
955.
Lilian Vivian Neide Maria Bruscato Berenice Maria Werle Waldemar de Carli Renata Alonso Gadi Soares Paulo Caleb de Lima Santos Júnior Emilio Hideyuki Moriguchi 《Arquivos brasileiros de cardiologia》2020,115(5):873
Background:Knowledge of environmental and genetic factors for healthy aging in elderly people is controversial. In addition to this evidence, few studies have been designed for this population.Objectives:To investigate the relationship between the most frequent apolipoprotein E (APOE) genotypes and mortality in very elderly individuals living in a community and to evaluate survival according to cardiovascular risk factors.Methods:A sample of 74 elderly individuals aged ≥ 80 years, from the Veranópolis Project cohort, was selected for APOE genotyping. At baseline, anthropometric variables, glucose and lipid levels, blood pressure, and lifestyle variables (smoking, alcohol consumption, and physical activity) were collected. The Bayer Activities of Daily Living Scale was applied to their caregivers. Total study follow-up was 21 years. Two-sided p < 0.05 was considered statistically significant.Results:There was no association between APOE genotypes and mortality. However, the risk of death in elderly smokers was 2.30 times higher (hazard ratio [HR], 95% CI 1.01 to 5.24); in individuals with diabetes, it was 3.95 times higher (HR, 95% CI 1.27 to 12.30) than in individuals without diabetes. Subjects who practiced vigorous physical activity had a 51% reduction in risk of death (HR = 0.49, 95% CI 0.27 to 0.88). For an increase of 1 mmHg in systolic blood pressure, there was a 2% reduction (HR = 0.98, 95% CI 0.97 to 0.99) in risk of death.Conclusion:In this sample population, APOE genotypes were not associated with mortality. However, classic cardiovascular risk factors may be important for overall mortality in the very elderly. 相似文献
956.
Ewa esawska Annamria Kincses Gabriella Spengler Wojciech Nitek Waldemar Tejchman Jadwiga Handzlik 《Chemical biology & drug design》2019,93(5):844-853
In order to extend knowledge about pharmacophoric features responsible for ABCB1 inhibitory properties of imidazolidin‐2,4‐dione derivatives, 1′‐[4‐(4‐(o‐methoxyphenyl)‐piperazin‐1‐yl)butyl]‐3′‐methyl‐spiro(fluoren‐9,5′‐imidazolidine)‐2′,4′‐dione ( 3 ) and its salt ( 4 ) with rhodanine‐3‐acetic acid ( RA ) were prepared and investigated by X‐ray diffraction method, as well as their efflux modulating effects in cancer cells (mouse T‐lymphoma), cytotoxic and antiproliferative activities were evaluated in vitro. The molecular geometry, intermolecular interactions, and crystal packing of base and acid forms of 3 were analyzed to see, if conformational changes influence the biological activities. The geometry of 2‐methoxyphenylpiperazine and 5‐spirofluorenehydantoin moieties was compared with other crystal structures containing these fragments. Our results indicated a very potent inhibitory action on ABCB1 pump, and significant cytotoxic and antiproliferative properties of 3 in T‐lymphoma, even more potent in the case of multidrug resistance cells. Furthermore, the compound 3 converted into the salt 4 of inactive acid ( RA ) has maintained both, the efflux pump inhibitory and antiproliferative activities, showing strong synergism with doxorubicin. A comparison of geometry of 3 in both crystal structures ( 3 and 4 ) shows a significant difference in the arrangement of piperazine ring with respect to the aliphatic linker. 相似文献
957.
958.
Sarah Saleem Elizabeth M McClure Shivaprasad S Goudar Archana Patel Fabian Esamai Ana Garces Elwyn Chomba Fernando Althabe Janet Moore Bhalachandra Kodkany Omrana Pasha Jose Belizan Albert Mayansyan Richard J Derman Patricia L Hibberd Edward A Liechty Nancy F Krebs K Michael Hambidge Pierre Buekens Waldemar A Carlo Linda L Wright Marion Koso-Thomas Alan H Jobe Robert L Goldenberg 《Bulletin of the World Health Organization》2014,92(8):605-612
Objective
To quantify maternal, fetal and neonatal mortality in low- and middle-income countries, to identify when deaths occur and to identify relationships between maternal deaths and stillbirths and neonatal deaths.Methods
A prospective study of pregnancy outcomes was performed in 106 communities at seven sites in Argentina, Guatemala, India, Kenya, Pakistan and Zambia. Pregnant women were enrolled and followed until six weeks postpartum.Findings
Between 2010 and 2012, 214 070 of 220 235 enrolled women (97.2%) completed follow-up. The maternal mortality ratio was 168 per 100 000 live births, ranging from 69 per 100 000 in Argentina to 316 per 100 000 in Pakistan. Overall, 29% (98/336) of maternal deaths occurred around the time of delivery: most were attributed to haemorrhage (86/336), pre-eclampsia or eclampsia (55/336) or sepsis (39/336). Around 70% (4349/6213) of stillbirths were probably intrapartum; 34% (1804/5230) of neonates died on the day of delivery and 14% (755/5230) died the day after. Stillbirths were more common in women who died than in those alive six weeks postpartum (risk ratio, RR: 9.48; 95% confidence interval, CI: 7.97–11.27), as were perinatal deaths (RR: 4.30; 95% CI: 3.26–5.67) and 7-day (RR: 3.94; 95% CI: 2.74–5.65) and 28-day neonatal deaths (RR: 7.36; 95% CI: 5.54–9.77).Conclusion
Most maternal, fetal and neonatal deaths occurred at or around delivery and were attributed to preventable causes. Maternal death increased the risk of perinatal and neonatal death. Improving obstetric and neonatal care around the time of birth offers the greatest chance of reducing mortality. 相似文献959.
960.
Noninvasive measurement of cardiovascular function in mice with high-temporal-resolution small-animal PET. 总被引:3,自引:0,他引:3
Michael C Kreissl Hsiao-Ming Wu David B Stout Waldemar Ladno Thomas H Schindler Xiaoli Zhang John O Prior Mayumi L Prins Arion F Chatziioannou Sung-Cheng Huang Heinrich R Schelbert 《Journal of nuclear medicine》2006,47(6):974-980
The aim of this study was to explore the feasibility of determining parameters of cardiovascular function in mice noninvasively by high-temporal-resolution imaging with a dedicated small-animal PET system. METHODS: Twenty-five anesthetized mice (28.8 +/- 4.6 g) were injected via an intravenous catheter with a 30-microL bolus of (18)F-FDG (8-44 MBq). The first 9 s of data were reconstructed into 30 frames of 0.3 s using filtered backprojection. The time-activity curve derived from a left ventricle volume of interest was corrected for tracer recirculation and partial volume. Cardiac output was calculated by the Stewart-Hamilton method, in which cardiac output is total injected activity divided by the area under the left ventricle time-activity curve. Cardiac output divided by body weight was defined as cardiac index; cardiac output divided by heart rate yielded the stroke volume. In 5 mice, measurements were repeated 2-4 times to assess reproducibility. In 4 mice, the hemodynamic response to dobutamine was examined by measuring heart rate, cardiac output, and stroke volume. RESULTS: The cardiac output averaged 20.4 +/- 3.4 mL/min; in the repeated measurements, the parameter displayed a mean percentage SD per mouse of 10% +/- 6%. The cardiac index averaged 0.73 +/- 0.19 mL/min/g and the stroke volume 45.0 +/- 6.9 microL, and both correlated with heart rate (r = 0.53, P = 0.007, and r = 0.49, P = 0.01, respectively). During dobutamine stress, heart rate increased from 423 +/- 50 to 603 +/- 30 beats/min (P = 0.002) and cardiac output increased from 18.5 +/- 1.9 to 32.0 +/- 4.2 mL/min (P = 0.008). CONCLUSION: Parameters of cardiovascular function can be measured in mice noninvasively by radionuclide angiography using high-temporal-resolution small-animal PET. Measured values of cardiac output and stroke volume are reproducible and comparable to those obtained with MRI. The approach permits the monitoring of changes in cardiovascular function in response to pharmacologic intervention. 相似文献