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Ultra-thin vapor chambers (UTVCs) are widely used to cool high-power electronics due to their excellent thermal conductivity. In this study, a UTVC of 82 mm × 58 mm × 0.39 mm with composite wick was prepared. The composite wick is composed of two layers of copper mesh and multiple spiral-woven meshes (SWMs), and the composite wick was applied in UTVC to improve liquid replenishment performance and temperature uniformity. Furthermore, the thermal performance of UTVCs with different support column diameters, filling ratios (FRs), and SWM structures was experimentally studied. The results found that the equivalent thermal conductivity (ETC) decreases as the diameter of the support column increases; the UTVC with 0.5 mm support column diameter has the highest ETC, at 3473 W/(m·K). Then, the effect of FR on the heat transfer performance of UTVCs with SWM numbers of 0, 1, 2, and 3 (0 SWMs, 1 SWM, 2 SWMs, 3 SWMs) is consistent, the 30% FR UTVC with 3 SWMs having the highest ETC, at 3837 W/(m·K). Finally, the increased number of SWMs can significantly improve the ultimate power of the UTVCs, the UTVC with 3 SWMs having the highest ultimate power, at 26 W. The above experimental studies indicate that the designed and manufactured UTVCs have great potential advantages in thermal dissipation for electronics.

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PURPOSE: To evaluate the effectiveness of microwave ablation (MWA) for the treatment of thyroid nodules according to nodule composition. MATERIALS AND METHODS: This study evaluated 171 patients with 180 benign thyroid nodules (BTNs) that had been treated with ultrasound-guided MWA. The volume reduction rate (VRR) of thyroid nodules and factors, which had an influence on the VRR, were assessed. Therapeutic success was defined as a >50% volume reduction at the 12-month follow-up. Multivariate regression analysis was used to identify independent predictors of VRR for BTNs after MWA treatment. RESULTS: The mean diameter and volume of the nodules were 4.3 ± 1.3 cm and 18.9 ± 2.1 ml, respectively. The VRRs at the 1-, 3-, 6-, 12-, 24-, and 36-month follow-ups were 47.1%, 68.2%, 79.7%, 87.4%, 90.1%, and 93.2%, respectively. Of the 180 BTNs, there were 87 solid, 74 predominantly solid, and 19 predominantly cystic nodules. Solid nodules showed significantly lower VRRs compared with the predominantly solid and predominantly cystic nodules at the 1-, 3-, and 6-month follow-ups. For the multivariate regression analysis, the cyst component was an active prognostic factor for the VRR at the 1-, 3-, and 6-month follow-ups; the cyst component was not significantly associated with the VRR at the 12-, 24-, and 36-month follow-ups. CONCLUSION: Our study suggested that ultrasound-guided MWA is an effective and safe procedure for the treatment of BTNs. Solid nodules indicate a lower VRR and less efficient than predominant solid nodules and predominant cystic nodules after MWA.

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INTRODUCTION: Piriformis muscle syndrome (PS) is a disorder encompassing a constellation of symptoms, including buttock and hip pain. In this study we aimed to assess the value of ultrasound (US) in the diagnosis of PS. METHODS: Thirty-three clinically diagnosed PS patients and 26 healthy volunteers underwent a clinical PS scoring examination and US and MRI assessment of the bilateral piriformis muscles. The areas under the receiver operating characteristic curves (AUROCs) of the US parameters (i.e., increased thickness [iTh] and increased cross-sectional area [iCSA]) for piriformis muscle were evaluated. RESULTS: On US and MRI, the thickness and CSA were increased in PS patients. The AUROCs for the iTh and iCSA for discriminating stage 0 (healthy volunteers) from stage 1 through stage 3 (PS patients) were 0.88 and 0.95, respectively. DISCUSSION: US may be a reliable technique for the clinical diagnosis of PS. Muscle Nerve 59:411-416, 2019.

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This study is to prospectively evaluate the efficiency of sonography for volvulus diagnosis in neonates with clinically suspected intestinal malrotation.A total of 83 patients with suspected intestinal malrotation who underwent detailed abdominal sonography and upper gastrointestinal contrast study were included. Malrotation was characterized by inversion of the superior mesenteric artery (SMA) and superior mesenteric vein (SMV) in sonographic examination. The "whirlpool sign" of Color Doppler Sonography was recognized as a characteristic for malrotation with volvulus. The degrees of rotation of the SMV winding around SMA were also detected by sonography. Surgery was performed in patients with sonography diagnosed malrotation.A total of 39 patients were sonographically diagnosed as malrotation which was subsequently confirmed by surgery. The sensitivity and positive predictive value of the sonographic diagnosis were both 100% (39/39). The sensitivity, specificity and accuracy of "whirlpool sign" for the detection of midgut volvulus were 95.2% (20/21), 88.9% (16/18), and 92.3% (36/39), respectively. Greater degrees of rotation (equal or greater than 720°) showed higher risk (odds ratio, 5.0; P < .01) for intestinal necrosis occurrence.Sonography is more accurate in diagnosing suspected malrotation than upper gastrointestinal contrast study. Specific sonographic "whirlpool sign" related to volvulus may be used as a potential indicator for intestinal necrosis. In addition, sonography can exclude malrotation and may help the diagnosis of other diseases, such as annular pancreas and duodenal atresia.

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BACKGROUND: For successful treatment for nonalcoholic steatohepatitis (NASH), it may be important to treat the individual causative factors. At present, however, there is no established treatment for this disease. Branched-chain amino acids (BCAAs) have been used to treat patients with decompensated cirrhosis. AIM: In order to elucidate the mechanisms responsible for the effects of BCAAs on hepatic steatosis and disease progression, we investigated the effects of BCAA supplementation in mice fed a choline-deficient high-fat diet (CDHF), which induces NASH. METHODS: Male mice were divided into four groups that received (1) choline-sufficient high fat (HF) diet (HF-control), (2) HF plus 2% BCAA in drinking water (HF-BCAA), (3) CDHF diet (CDHF-control), or (4) CDHF-BCAA for 8weeks. We monitored liver injury, hepatic steatosis and cholesterol, gene expression related to lipid metabolism, and hepatic fat accumulation. RESULTS: Serum alanine aminotransferase (ALT) levels and hepatic triglyceride (TG) were significantly elevated in CDHF-control relative to HF-control. Liver histopathology revealed severe steatosis, inflammation, and pericellular fibrosis in CDHF-control, confirming the NASH findings. Serum ALT levels and hepatic TG and lipid droplet areas were significantly lower in CDHF-BCAA than in CDHF-control. Gene expression and protein level of fatty acid synthase (FAS), which catalyzes the final step in fatty acid biosynthesis, was significantly decreased in CDHF-BCAA than in CDHF-control (P<0.05). Moreover, hepatic total and free cholesterol of CDHF-BCAA was significantly lower than those of CDHF-control. CONCLUSIONS: BCAA can alleviate hepatic steatosis and liver injury associated with NASH by suppressing FAS gene expression and protein levels.

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BACKGROUND AND AIM: The prevalence of nonalcoholic fatty liver disease (NAFLD) is higher in men than in women, but according to some epidemiological studies, this gender difference disappears after menopause. Estrogen therapy protects against NAFLD and nonalcoholic steatohepatitis (NASH) after menopause. We investigated the therapeutic effect of raloxifene, a second-generation selective estrogen-receptor modulator, on NASH induced by a choline-deficient high-fat (CDHF) diet in female ovariectomized (OVX) mice. METHODS: Seven-week-old female C57BL/6J mice were divided into three experimental groups as follows: (1) sham operation (SHAM group), (2) ovariectomy (OVX group), and (3) ovariectomy + raloxifene (intraperitoneal injection, 3 mg/kg body weight/day; OVX + RLX group). These three groups of mice were fed a CDHF diet for 8 weeks; choline-sufficient high-fat (CSHF) diet was used as control diet. Serum biochemical indicators of hepatic function and liver histological changes were evaluated. RESULTS: Compared with CSHF diet, ovariectomy enhances liver injury and fibrosis in CDHF diet-fed mice. Serum alanine aminotransferase (ALT) levels were significantly lower in the OVX + RLX group than in the OVX group. The OVX group developed extensive steatosis with inflammation and fibrosis. Lobular inflammatory scores and fibrosis staging in the OVX + RLX group were significantly lower than in the OVX group. Furthermore, the OVX + RLX group exhibited significantly higher expression of hepatic estrogen receptor-α, which was significantly lower in the OVX group than in the SHAM group. CONCLUSIONS: Raloxifene may ameliorate progression of liver fibrosis of NASH induced by CDHF diet in ovariectomized female mice, and up-regulation of estrogen receptor-α may play an important role in the beneficial effects of raloxifene on NASH.

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Obtaining a better understanding of the mechanisms associated with hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) loss in patients with hepatitis B virus (HBV) is important for treating patients with chronic hepatitis B. We herein describe the case of a patient with HBV and human immunodeficiency virus whose chronic hepatitis was stabilized due to HBe and HBs seroconversion with the emergence of lamivudine-associated and core mutations after CD4 elevation. A full-length HBV DNA analysis indicated that HBsAg had been lost after the development of the rtS143T mutation, which corresponded to the emergence of the sF134L and core mutations. The details of this case shed some light on the mechanisms associated with HBsAg and HBeAg clearance.

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@#Objective To analyze the changes in Th1/Th2 cytokines level in chronic hepatitis B patients during Adefovir dipivoxil therapy.Methods The serum levels of TNF-α, IFN-γ, IL-10, IL-6, IL-4 and IL-2 were measured in chronic hepatitis B (CHB) patients using Cytotoxic Bead Array (CBA) technique.Results After 12, 24, and 48 weeks of treatment, the serum levels of TNF-α, IFN-γ, IL-10, IL-4 and IL-2 in CHB patients were significantly increased compared to the baseline (P < 0.05) .At the 12th week of treatment, IL-6 was negatively correlated with HBV DNA and after 24 weeks of treatment, IL-6, IL-10 and TNF-α were negatively correlated with HBV DNA (P < 0.05) .Conclusion Adefovir dipivoxil may inhibit HBV DNA replication through the immune pathway.