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51.
To investigate the functional involvement of the pineal gland in circadian expression of the rat period homolog gene (rPer2) in the suprachiasmatic nucleus (SCN) and peripheral tissues, we performed Northern blot analysis in tissues from pinealectomized rats. The ectomy did not have any significant effects on rPer2 mRNA expression patterns both in a daily light-dark condition and in a constant darkness. These results suggest that the rhythmic secretion of pineal melatonin is not essential for the circadian expression of clock genes in the SCN and other peripheral tissues of rats.  相似文献   
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BACKGROUND: Controversy still remains regarding the long-term results and indications for axillofemoral bypass (AxFB). A comparison of axillobifemoral bypass (AxBFB) and aortobifemoral bypass (ABFB) was thus conducted to determine whether AxFB is an acceptable alternative vascular procedure to anatomic bypass for high-risk patients. METHODS: Sixty-three patients who underwent a total of 25 AxBFBs and 38 ABFBs for aortoiliac occlusive disease were reviewed retrospectively, and both univariate and multivarate analyses were perfomed. RESULTS: The overall survival was 82.8% at five years. A univariate analysis revealed significantly lower survival rates for patients with limb-threatening ischemia, coronary disease, and cerebrovascular disease. A multivariate analysis disclosed no significant factors influencing survival rates. The overall primary patency was 79.8% at five years. The primary patency rates for AxBFB (67.7% at five years) were significantly lower than for ABFB (88.5% at five years) based on a univariate analysis (p=0.0045). In addition, the secondary patency rates for AxBFB (80.3% at five years) were significantly lower than for ABFB (96.5% at five years, p=0.0025). A multivariate analysis disclosed significantly lower primary patency rates for grafts with a higher angiographic outflow score and simultaneous infrainguinal reconstructive procedures, but the differences between AxBFB and ABFB were not significant. CONCLUSIONS: The survival and primary patency for the AxBFB group were both inferior to the ABFB group, however a multivarate analysis disclosed no significant differences between the two groups. Poor femoral run-off and the presence of synchronous infrainguinal reconstructive procedures significantly affected graft patency, and these factors modulated the patency of AxBFB. AxFB for aortoiliac occlusive disease is therefore considered to be an acceptable procedure in appropriately selected patients.  相似文献   
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To investigate the molecular mechanism that regulates circadian rhythms in mammalian peripheral tissues, we examined the phase shifts evoked by light exposure in the circadian mRNA expression rhythms of mammalian Period genes (mPer1, mPer2 and mPer3) and a clock-controlled gene Dbp, in the mouse heart, by Northern blot analysis. The light pulse did not induce any acute mRNA expression of mPer in the heart, but the pulse gave rise to phase shifts in the circadian mRNA rhythms. On the first day after the exposure, only mPer1 mRNA showed a phase shift, whereas obvious phase shifts were not observed in the rhythms of mPer2, mPer3 and Dbp mRNAs. On the second day, phase shifts occurred to a similar extent in the mRNA rhythms of all four genes examined. The rhythm of mPer1 mRNA shifted fastest among those of the three mPers. Therefore mPer1 seems to play an important role in phase resetting of mammalian peripheral oscillators. Immediate responses to light pulses in mRNA expression of mPers may not be required for phase shifting of peripheral circadian oscillators. Our findings suggest that mammals require more than one day to have peripheral oscillators entrained to a new daily schedule.  相似文献   
55.
From 1990 to 1999, 19 patients underwent aortic root replacement. Annulo-aortic ectasia was observed in 14 patients, aortic dissection in 4, and aortitis in 1. Mean aortic cross-clamp times and cardiopulmonary bypass times were 163 +/- 44 and 247 +/- 99 min, respectively. Concomitant procedures were coronary artery bypass grafting in 3 patients, aortic arch replacement in 1 and aortic arch replacement and elephant trunk method in 2. There were two hospital deaths due to cardiac failure. There was one late death because of pharyngeal cancer 1.7 years after the operation. Seventeen survivors were followed for a mean duration of 4.4 years (0.6-9.3 years). There were no complications during this period. In conclusion, good results were obtained by modified Bentall operation.  相似文献   
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A 58-year-old woman with bronchiectasis presented with massive hemoptysis and severe respiratory failure, which required long-term extracorporeal membrane oxygenation with continuous heparin infusion. Bronchial artery embolization using hydrogel coils, which provide a greater volume occlusion than bare platinum coils, was performed; hemoptysis stopped and she fully recovered. No recanalization was observed on follow-up computed tomography angiography 2 months postbronchial artery embolization, and there had been no recurrence of bleeding at the time of this report (at least 6 months). Although continuous anticoagulation during extracorporeal membrane oxygenation might hinder complete vessel occlusion by metallic coils or induce early recanalization (because the homeostatic mechanism of coils depends on the patient''s coagulability), our experience showed that bronchial artery embolization using hydrogel coils was effective and safe. Additionally, this case presents a successful example of anticoagulation management for patients with hemoptysis on extracorporeal membrane oxygenation who undergo bronchial artery embolization using coils.  相似文献   
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Stress myocardial perfusion imaging (MPI) is the preferred test in patients with intermediate-to-high clinical likelihood of coronary artery disease (CAD) and can be used as a gatekeeper to avoid unnecessary revascularization. Cardiac magnetic resonance (CMR) has a number of favorable characteristics, including: (1) high spatial resolution that can delineate subendocardial ischemia; (2) comprehensive assessment of morphology, global and regional cardiac functions, tissue characterization, and coronary artery stenosis; and (3) no radiation exposure to patients. According to meta-analysis studies, the diagnostic accuracy of perfusion CMR is comparable to positron emission tomography (PET) and perfusion CT, and is better than single-photon emission CT (SPECT) when fractional flow reserve (FFR) is used as a reference standard. In addition, stress CMR has an excellent prognostic value. One meta-analysis study demonstrated the annual event rate of cardiovascular death or non-fatal myocardial infarction was 4.9% and 0.8%, respectively, in patients with positive and negative stress CMR. Quantitative assessment of perfusion CMR not only allows the objective evaluation of regional ischemia but also provides insights into the pathophysiology of microvascular disease and diffuse subclinical atherosclerosis. For accurate quantification of myocardial perfusion, saturation correction of arterial input function is important. There are two major approaches for saturation correction, one is a dual-bolus method and the other is a dual-sequence method. Absolute quantitative mapping with myocardial perfusion CMR has good accuracy in detecting coronary microvascular dysfunction. Flow measurement in the coronary sinus (CS) with phase contrast cine CMR is an alternative approach to quantify global coronary flow reserve (CFR). The measurement of global CFR by quantitative analysis of perfusion CMR or flow measurement in the CS permits assessment of microvascular disease and diffuse subclinical atherosclerosis, which may provide improved prediction of future event risk in patients with suspected or known CAD. Multi-institutional studies to validate the diagnostic and prognostic values of quantitative perfusion CMR approaches are required.  相似文献   
60.
IntroductionPrevious studies exploring associations of physical inactivity, obesity, and out-of-pocket expenditure (OOPE) mainly used traditional linear regression, and little is known about the effect of both physical inactivity and obesity on OOPE across the percentile distribution. This study aims to assess the effects of physical inactivity and obesity on OOPE in China using a quantile regression approach.MethodsStudy participants included 10,687 respondents aged 45 years and older from the recent wave of the China Health and Retirement Longitudinal Study in 2015. Linear regression and quantile regression models were used to examine the association of physical activity, body weight with annual OOPE.ResultsOverall, the proportion of overweight and obesity was 33.2% and 5.8%, respectively. The proportion of individuals performing high-level, moderate-level, and low-level physical activity was 55.2%, 12.7%, and 32.1%, respectively. The effects of low-level physical activity on annual OOPE were small at the bottom quantiles but more pronounced at higher quantiles. Respondents with low-level activity had an increased annual OOPE of 26.9 USD, 150.3 USD, and 1,534.4 USD, at the 10th, 50th, and 90th percentiles, respectively, compared with those with high-level activity. The effects of overweight and obesity on OOPE were also small at the bottom quantiles but more pronounced at higher quantiles.ConclusionInterventions that improve the lifestyles and unhealthy behaviors among people with obesity and physical inactivity are likely to yield substantial financial gains for the individual and health systems in China.  相似文献   
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