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991.
Fetal lung volume measurements: determination with MR imaging--effect of various factors 总被引:3,自引:0,他引:3
Ward VL Nishino M Hatabu H Estroff JA Barnewolt CE Feldman HA Levine D 《Radiology》2006,240(1):187-193
PURPOSE: To retrospectively determine the effect of gestational age (GA), imaging plane, section thickness, and inter- and intraobserver variability on fetal lung volume (FLV) measurements obtained with magnetic resonance (MR) imaging in a cohort of fetuses without thoracic abnormalities. MATERIALS AND METHODS: Institutional review board approval was obtained. Informed consent for this retrospective cohort study was waived, and the conduct of this study was HIPAA compliant. FLV was measured in 30 fetuses (GA, 17-36 weeks) referred for MR imaging for indications other than pulmonary abnormalities. Measurements were made on single-shot fast spin-echo images by tracing free-form regions of interest on individual consecutive sections in the transverse, sagittal, and coronal planes. Measurements were performed twice by two observers independently. Correlations between FLV and GA, imaging plane, and section thickness were assessed, as were intra- and interobserver variability. Time to perform FLV was assessed in a subset of fetuses. RESULTS: Total FLV ranged from 2 to 110 mL. Mixed-effects regression model showed significant quadratic trend in FLV with increasing GA, with comparable strength of correlation (r = 0.89-0.91) in the three imaging planes of measurement. Intraobserver agreement was good in all three planes (r = 0.65-0.83) and was highest in the transverse plane. Interobserver agreement was good in all three planes (r = 0.68-0.76). FLV showed no significant dependence on section thickness (P = .23) or imaging plane (P = .82). Mean time to obtain FLV measurements ranged from 48 seconds at GA of 21 weeks to 77 seconds at GA of 29-30 weeks. CONCLUSION: GA-based FLV measurements obtained with MR images are independent of section thickness and imaging plane and can be performed with good inter- and intraobserver agreement in less than 2 minutes. 相似文献
992.
Eccentric contractions (ECC) induce myofibrillar collapse, edema, and inflammation in muscle cells. Although apoptosis of
myonuclei following ECC is activated during the inflammatory phase, the apoptosis response of the regenerative phase remains
to be elucidated. The aim of the present study was to determine the inflammatory and regenerative phase of the apoptosis responses
induced by ECC. In anesthetized rats, the tibialis anterior muscles were subjected to ECC repeated 40 times, evoked by surface
electric stimulation (100 Hz, 10 V) with mechanical muscle stretch. Apoptosis was examined in the control group and in groups
1, 3, 7, and 14 days after ECC (each group, n = 4–6). Terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL)-positive myonuclei were assessed by
further labeling with dystrophin staining and DAPI. The expression of proteins related to apoptosis (Bcl-2 and Bax) was examined
by Western blot assay. At 1 and 3 days, focal edema and necrotic myofibers invaded by mononuclear phagocytes were present,
whereas regenerated myofibers with central nuclei were detected at 7 and 14 days. The occurrence of TUNEL-positive myonuclei
increased significantly at 7 (7.0 ± 1.5%) and 14 days (5.6 ± 0.6%) compared with control (0.9 ± 0.5%). Further we found that
myonuclear apoptosis was restricted to the subsarcolemmal space at 7 and 14 days and markedly absent from the central nucleus.
The Bax/Bcl-2 ratio was significantly higher at 3 (4.5 ± 0.9) and 7 days (3.4 ± 0.5) after ECC. In conclusion, myofiber apoptotic
responses following ECC are present not only in the inflammatory phase but also persist during the regenerative phase. 相似文献
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Hiromi Ogino Kaori Yamada Mizuki Yuhara Saori Tsuchida Kayoko Maezawa Junko Kizu Seiji Hori 《Journal of infection and chemotherapy》2009,15(2):113-117
We studied the effect of fluoroquinolones (FQs) on carrageenan-induced edema in the rat footpad. Ciprofloxacin, gatifloxacin,
sparfloxacin, norfloxacin, and enoxacin (s.c., 100 mg/kg), which have piperazinyl and/or cyclopropyl groups, inhibited carrageenan-induced
edema, whereas levofloxacin, tosufloxacin, and pazufloxacin did not. The reduction of edema by ciprofloxacin, sparfloxacin,
and enoxacin was abolished by pretreatment with mifepristone, an antagonist of the glucocorticoid receptor. These results
suggest that FQs with piperazinyl and/or cyclopropyl groups can modify biological responses through enhancing the glucocorticoid-glucocorticoid
receptor system. 相似文献
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Taro Nakatsu Takaaki Koshiji Yutaka Sakakibara Koji Hagio Masanosuke Ishigami Yuichiro Arima Mitsuhiko Kitaoka 《General thoracic and cardiovascular surgery》2010,58(8):423-426
A 65-year-old woman with a 9-year surgical history of a left breast phyllodes tumor was admitted with progressive chest pain
on effort. Computed tomography showed severe stenosis of the main pulmonary artery, with the mass originating from the ventricular
septum. We planned to resect the tumor the next day. However, the next morning a pulmonary artery embolism occurred, and she
developed dyspnea and lost consciousness. After carrying out cardiopulmonary resuscitation, we performed a life-saving operation.
We successfully resected the huge tumor as far as possible from the right ventricle via a right atrial (RA)-tomy. However,
her consciousness did not improve to better than Glasgow Coma Scale grade 7. She died from suffocation caused by metastasis
invading her airway despite undergoing tracheotomy on the 77th postoperative day. 相似文献