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101.
102.
For gas metal arc welding (GMAW), increasing the welding current is the most effective way to improve welding efficiency. However, much higher current decreases the welding quality as a result of metal rotating-spray transfer phenomena in the high-current GMAW process. In this work, the external axial magnetic field (EAMF) was applied to the high-current GMAW process to control the metal transfer and decrease the welding spatters. A unified arc-droplet coupled model for high-current GMAW using EAMFs was built to investigate the metal rotating-spray transfer behavior. The temperature fields, flow fields in the arc, and droplet were revealed. Considering all the heat transferred to the molten metal, the Joule heat was found to be the dominant factor affecting the droplet temperature rise, followed by the anode heat. The conductive heat from the arc contributed less than half the value of the other two. Considering the EAMFs of different alternating frequencies, the arc constricting effects and controlled metal transfer behaviors are discussed. The calculated results agree well with the experimental high-speed camera observations. 相似文献
103.
Koji Shindo Shinichi Aishima Kenoki Ohuchida Minoru Fujino Yusuke Mizuuchi Masami Hattori Takao Ohtsuka Shoji Tokunaga Kazuhiro Mizumoto Masao Tanaka Yoshinao Oda 《Virchows Archiv : an international journal of pathology》2014,465(3):265-273
A thickened, enhanced cyst wall on imaging examinations is one of the “worrisome features” described in the consensus guidelines for management of intraductal papillary mucinous neoplasm of the pancreas (IPMN). Podoplanin (PDPN) expression by cancer-associated fibroblasts is known to be an indicator of poor prognosis in some types of cancer. We performed immunohistochemical staining for alpha-smooth muscle actin (α-SMA) in IPMN lesions and determined the pathological wall thickness by measuring the thinnest and thickest α-SMA-positive parts of the wall of the largest cyst in each case, and the mean of these two values was recorded as the wall thickness. The thickness of the pathological wall increased with progression from IPMN with low-grade dysplasia to IPMN with an invasive carcinoma. The pathological wall was thicker in IPMN with main duct involvement, nongastric-type IPMN, and IPMN with mural nodules. We also stained for PDPN and assessed the thickness of cyst wall staining as for α-SMA. The thickness of the PDPN-positive cyst wall varied in a pattern similar to the thickness of the α-SMA-positive pathological cyst wall. PDPN-positive stromal fibroblasts in the invasive component of IPMN-IC were evaluated as a ratio to α-SMA-positive fibroblasts. A high ratio (>50 %) of PDPN-positive stromal fibroblasts was a predictor of poor outcome. PDPN expression in the cyst wall correlates with the progression of IPMN. PDPN may be a significant prognostic marker of IPMN-IC. 相似文献
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Autoantibodies to RuvBL1 and RuvBL2: A Novel Systemic Sclerosis–Related Antibody Associated With Diffuse Cutaneous and Skeletal Muscle Involvement 下载免费PDF全文
106.
S Makita T Onoda M Ohsawa F Tanaka T Segawa T Takahashi K Satoh K Itai K Tanno K Sakata S Omama Y Yoshida Y Ishibashi T Koyama T Kuribayashi K Ogasawara A Ogawa A Okayama M Nakamura 《Atherosclerosis》2012,224(1):222-227
Background and methodsThere is controversy about the association between mild-to-moderate alcohol consumption and a reduced risk of cardiovascular diseases. The relationships between daily alcohol consumption and the incidence of acute myocardial infarction (MI) or ischemic stroke (IS) were examined in men in a community-based, prospective cohort study (n = 8014, age 40–80 years, mean age = 64.1 years). Alcohol consumption was categorized into 3 groups (A1, none or occasional; A2, ≤25 g/day; A3, >25 g/day as ethanol) at baseline.ResultsDuring the mean follow-up of 5.5 years, 53 MIs and 186 ISs occurred. On Cox regression analysis adjusted for age, hypertension, diabetes, dyslipidemia, smoking index, and body mass index (BMI), the hazard ratio (HR) for incident MI was significantly lower in the A2 group than in the A1 group (HR = 0.49, p = 0.043). The HR for incident MI in the A3 group tended to be lower than in the A1 group (HR = 0.53, p = 0.10). In obese subjects, while a significantly lower HR for incident MI in the A2 group was retained (HR = 0.29, p = 0.049), no significant difference in the HR of the A3 group compared with the A1 group was found. No significant differences were found in the IS-free curve among the 3 groups of alcohol consumption.ConclusionsAlcohol consumption may have a protective effect on the onset of MI but not on IS in the general population. A U-shaped relation between alcohol consumption and incident MI was found in obese subjects. An appropriate limit for daily alcohol consumption, depending on the risk of ischemic heart disease, may need to be established. 相似文献
107.
Honda H Ueda M Kojima S Mashiba S Michihata T Takahashi K Shishido K Akizawa T 《Atherosclerosis》2012,220(2):493-501
Background and objectivesHere, we assessed the impact of oxidized high-density lipoprotein (oxHDL), dysfunctional HDL, on mortality and cardiovascular disease (CVD) events in prevalent HD patients and compared oxHDL to interleukin-6 (IL-6), a strong predictor of CVD events in HD patients.Design, setting, participants, and measurementsThis prospective study examined a cohort of prevalent HD patients (n = 412). Blood samples were obtained at baseline to measure lipids, high-sensitive C-reactive protein (hsCRP), IL-6, oxidized low-density lipoprotein, N-terminal pro B-type natriuretic peptide, intercellular adhesion molecule 1 (ICAM-1), myeloperoxidase, adiponectin, and oxHDL. Carotid intima-media thickness (CIMT) was assessed at baseline and 3-year follow-up. Nutritional status was assessed by subjective global assessment (SGA), body mass index, and geriatric nutritional risk index (GNRI). After the baseline assessment, study patients were prospectively followed up (mean observational period, 40 months).ResultsAt baseline, patients with high oxHDL had a worse nutritional state and higher HDL-cholesterol (HDL-chol), ICAM-1, and adiponectin levels and a higher oxHDL/HDL-chol ratio than low oxHDL patients. A combination of high oxHDL and high IL-6 was significantly associated with increased CIMT at baseline and a larger increase in CIMT at 3-year follow-up. High oxHDL did not predict all-cause mortality; however, it was significantly associated with CVD-related mortality and composite CVD events, particularly with concomitant high IL-6. These associations were confirmed in multivariate Cox hazard models adjusted with confounding variables.ConclusionsHigh oxHDL, particularly with concomitant high IL-6, may be associated with an increased risk of CVD events and CVD-related mortality in prevalent HD patients. 相似文献
108.
Tsuji Y Hiraki Y Matsumoto K Mizoguchi A Sadoh S Kobayashi T Sakamoto S Morita K Yukawa E Kamimura H Karube Y 《Scandinavian journal of infectious diseases》2012,44(8):626-629
We evaluated the pharmacokinetics of linezolid in the case of an obese Japanese patient (body weight 116 kg; body mass index 37 kg/m(2)). Linezolid was administered at a dose of 600 mg by intravenous drip infusion for 60-90 min at 12-h intervals. The results showed increased clearance of linezolid and a reduced serum concentration compared to population pharmacokinetic parameters, with trough levels below the 90% minimum inhibitory concentration. However, linezolid was effective for improving lung infection and inflammation in our patient, which may be due to its particularly effective transfer into lung tissues. Linezolid undergoes slow non-enzymatic oxidation in vivo that may be increased in obese patients, and this may account for the greater clearance. Our findings are useful for the planning of linezolid therapy in obese patients. 相似文献
109.
This study aimed to develop a criterion for screening high risk elderly using Demura's fall risk assessment chart (DFRA), compared with the Tokyo Metropolitan Institute of gerontology (TMIG) fall risk assessment chart. Participants included 1122 healthy elderly individuals aged 60 years and over (380 males and 742 females) 15.8% of whom had experienced a fall. We assessed fall risk of the elderly by DFRA and TMIG. To develop a criterion for screening high fall risk subjects among community-dwelling elderly, receiver-operating-characteristic (ROC) analysis was conducted using fall experience (separated into the categories of faller and non-faller) and the following fall risk scale scores: (1) TMIG score, (2) DFRA score, and (3) potential for falling score according to the DFRA (summing the scores of three items). In ROC analyses, the area under the ROC curve (AUC) for evaluating the potential for falling gave a value of 0.797 (95% CI=0.759-0.834) which proved better than the evaluation of the overall TMIG (0.654, 95% CI=0.600-0.706) and DFRA scores (0.680, 95% CI=0.633-0.727). Assessment of the potential for falling and fall experience are of benefit in screening for elderly persons deemed to be at a high fall risk. Further examinations based on the prospective data setting will be required. 相似文献
110.