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101.
Renal artery stenosis (RAS) is the most common cause of secondary hypertension, via increases in plasma renin–angiotensin–aldosterone levels. Renal artery stenosis is diagnosed from blood examinations such as renin activity and from imaging examinations such as sonography. Patients are required to lie on the bed for 30 min before and during phlebotomy, since plasma renin activity is easily altered by posture. However, no such pre‐examination rest is required for sonography. The present study therefore investigated the possible influence of resting before examination on Doppler parameters used for the diagnosis of RAS. Subjects comprised 55 healthy young adults (24 males, 31 females; mean age, 22 ± 1 years). Sonographic measurements were made shortly after subjects entered the examination room and again after 30 min of rest lying on a bed. Median peak systolic velocity in the renal artery was significantly decreased after rest (106 cm/s, interquartile range (IQR) 96–121 cm/s) compared with before rest (120 cm/s, IQR 107–135 cm/s; p < .001). Median acceleration time in the intra‐renal segmental artery was also significantly shorter after rest (49 ms, IQR 38–54 ms) compared to before rest (50 ms, IQR 38–59 ms; p = .039). The present results suggest that serious consideration should be given regarding whether pre‐examination resting is needed to accurately interpret Doppler measurements of renal blood flow when diagnosing RAS from sonography.  相似文献   
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103.
The development of quantitative gated single-photon emission computed tomography (SPECT) has enabled the assessment of left ventricular perfusion, function and wall thickness in a single examination. Accordingly, the present study used gated SPECT to assess the benefit of coronary artery bypass grafting (CABG) in patients with coronary artery disease; 47 of those patients were evaluated before and 5 months after CABG. As a result of coronary revascularization, a significant improvement was observed in global ejection fraction (50+/-12 --> 53+/-11%; p<0.05). In 107 revascularized territories, the average regional reversible defect score (0.8+/-0.5 --> 0.2 +/-0.3; p<0.0001), average regional perfusion score at rest (0.6+/-0.6 --> 0.3+/-0.4; p<0.0001), average regional wall motion score (0.9+/-0.7 --> 0.7+/-0.5; p<0.05), and end-diastolic wall thickness (8.1+/-1.3 --> 8.6+/-1.5 mm; p<0.0005) all improved significantly. Even in 34 non-revascularized territories, the average regional reversible defect score (0.5+/-0.7 --> 0.2+/-0.5; p<0.03), average regional wall motion score (0.8+/-1.1 --> 0.5 +/-1.0; p<0.03) and end-diastolic wall thickness (8.0+/-1.4 --> 9.1+/-2.0 mm; p<0.03) all improved significantly. These results indicate that improvement in myocardial ischemia, hibernation and left ventricular function with CABG can be assessed in detail with gated SPECT.  相似文献   
104.
This paper shows how protonated 3,4-ethylene dioxythiophene moieties can be used as an end group to make organic conductors. An organic semiconductor 2,5-bis(5-(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)-3-dodecylthiophen-2-yl)thieno[3,2-b]thiophene is designed and synthesized. This molecule could be doped by protonic acid in both solution and solid-state, resulting in a broad absorption in the near-infrared range corresponding to polaron and bipolaron absorption. Electrical conductivity of ca. 0.1 S cm−1 was obtained at 100 °C (to avoid the water uptake by the acid). The adducts with protons bound at the end-thiophene α-position were confirmed by 1H Nuclear Magnetic Resonance spectra.

The use of protonated 3,4-ethylenedioxythiophene moieties as an end group could be a promising approach to prepare organic conductors.  相似文献   
105.
BackgroundManagement of pacemaker (PM) infections among advanced aged patients possesses particular clinical challenges due to higher rates of concurrent cardiovascular disease and medical comorbidities. Novel leadless cardiac pacemakers (LCPs) may provide new opportunities for better management options in this population, however, there is limited data especially in Asian populations to guide the decision making.MethodsWe reviewed 11 octogenarians (median age: 86 [minimum 82–maximum 90] years; male: 73%; median body mass index (BMI): 20.1 kg/m2) who received Micra Transcatheter Pacing System (Medtronic Inc, Minneapolis, MN) implantations following transvenous lead extractions (TLEs) for PM infections. ResultsAll patients had more than two medical comorbidities (average 3.7 comorbidities). The indications for LCP implantations were atrioventricular block in four patients, atrial fibrillation bradycardia in five, and sinus node dysfunction in two. Eight patients (73%) were bridged with temporary pacing using active fixation leads (median interval of 14.0 days), while one with severe dementia underwent a concomitant LCP implantation and TLE during the same procedure. Successful TLEs and LCP implantations were successfully accomplished in all without any complications. The median time from the TLE procedure to discharge was 22 days (minimum 7–maximum 136). All patients remained free of infections during a mean follow-up period of 17.2 ± 6.5 months.ConclusionsLCP implantations were safe and effective after removing the entire infectious PM system in all octogenarians. The novel LCP technology may offer an alternative option for considering a re-implantation strategy after transvenous PM infections in elderly patients, particularly those with severe frailty and PM dependency.

The incidence of cardiac pacemaker (PM) infections among patients with an advanced age has been increasing owing to the continually widening indications and growing number of generator replacements.[13] In current clinical practice, there is a class l indication for removing all hardware in the case of a proven or suspected device infection, and after a recovery window, a new conventional PM is implanted in PM dependent patients.[1,4,5] However, this management for the elderly population is one of the most sensitive issues, since they possess particular clinical challenges due to higher rates of concurrent cardiovascular disease and medical comorbidities.[610]Recently, the implantation of a Micra Transcatheter Pacing System (Medtronic Inc, Minneapolis, MN) has emerged as a new option for PM re-implantations after the removal of infectious PMs.[1117] Without the use of leads and a device pocket, this leadless cardiac pacemaker (LCP) potentially reduces the risk of pocket infections and lead associated endocarditis.[16,17] However, there have not been enough data supporting the feasibility of leadless PM implantations following the removal of infectious PMs in people with an older age, particularly in octogenarians. Furthermore, there has been no data regarding those therapeutic strategies in Asian populations who have a low body mass index (BMI) and are at a higher risk of a transvenous lead extraction (TLE) procedure. Therefore, in this case series, we sought to characterize the procedure for LCP implantations following TLEs of infected PMs in octogenarians at 2 Japanese high-volume centers.  相似文献   
106.
Increasing fat burning during physical activity is thought to be an effective strategy for maintaining health and preventing lifestyle-related diseases, such as obesity and diabetes. In recent years, medium-chain triglycerides (MCTs) have gained attention as a dietary component for increasing fat-burning. However, this fat-burning effect has been unclear in people with high body mass index (BMI). Therefore, we aimed to clarify the effects of 2 g of daily ingestion of MCTs over 2 weeks on substrate oxidation during low-intensity physical activity in sedentary (i.e., with no exercise habit) subjects with a BMI from 25 (kg/m2) to less than 30, which is classified as obese in Japan. A placebo-controlled, randomized, double-blind, crossover study with a 2-week washout period was conducted. The rate of fat oxidation as well as the respiratory exchange ratio (RER) during exercise (with a cycle ergometer at a 20-watt load) were measured with a human calorimeter. MCTs ingestion significantly increased fat oxidation during physical activity and decreased RER compared to long-chain triglycerides ingestion. In conclusion, we suggest that daily ingestion of 2 g of MCTs for 2 weeks increases fat burning during daily physical activities in sedentary persons with a BMI ranging from 25 to less than 30.  相似文献   
107.
Pleomorphic xanthoastrocytomas (PXAs) are rare low-grade astrocytic tumors that typically present as superficial nodular cystic tumors of the cerebrum attached to the leptomeninx. Histologically, they are pleomorphic, hypercellular glial neoplasms. Despite the presence of microscopic pleomorphism, patients’ postoperative prognosis is generally good. Anaplastic PXAs (APXAs) have a high mitotic index and patients with APXAs have a worse prognosis than patients with PXAs. Here, we report an autopsy case of APXA initially diagnosed as PXA. After gross total resection, the tumor recurred and was diagnosed as an APXA; thereafter, the patient died. An autopsy revealed that the tumor had relapsed at the primary site and had spread to the leptomeningeal space while concurrently invading the cerebrum including the periventricular area forming multifocal lesions. The histological findings of the autopsy were similar to those for epithelioid glioblastoma (EGBM) and small cell glioblastoma (SCGBM). In particular, the periventricular area with multifocal lesions was composed of SCGBM-like cells. It has been shown that multifocal lesions are frequently identified in patients with SCGBM. This is the first histopathologically confirmed case of APXA-related tumor presenting with periventricular extension and multifocal lesion formation. The periventricular extension might be a feature of PXAs and APXAs. However, suspected periventricular spread on imaging in past cases of PXAs and APXAs might instead represent the malignant transformation of these tumors to glioblastoma-like high-grade tumors, which often show SCGBM-like histological patterns.  相似文献   
108.
109.
Today's advances in diagnostic image-technologies often enable us to find small lung cancers. However, we have few definite strategies including how to diagnosis and treat them. In this study, we performed a retrospective analysis of 122 consecutive patients who underwent surgery for non-small cell lung cancer 20 mm or less in diameter to clarify the clinical features of small lung cancer. Of 122 patients, there were 114 patients of pN0, and 8 patients with lymph node metastasis. Seventy three patients underwent lobectomy, 45 underwent segmentectomy, and 4 underwent wedge resection based on the findings of preoperative CT and anatomical and oncological view during operation. Overall survival rate( OS) and progression free survival( PFS) at 3-year was, 94% and 84%, respectively. There were no differences in OS or PFS between lobectomy group and limited resection group, which might suggest that we adapted appropriate surgical procedures. Multivariate analysis revealed that pathological pleural invasion, lymphatic vessel invasion, and vascular vessel invasion were likely to be unfavorable prognostic-factors. We believe that further investigations should be required to clarify the characteristics of small lung cancer.  相似文献   
110.
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