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The MERA monopivot centrifugal pump has been developed for use in open‐heart surgery, circulatory support, and bridge‐to‐decision for up to 4 weeks. The pump has a closed‐type, 50‐mm diameter impeller with four straight paths. The impeller is supported by a monopivot bearing and is driven by a radial‐flux magnet‐coupling motor. Because flow visualization experiments have clarified sufficient pivot wash and stagnation at the sharp corner of the pivot support was suggested, sharp corners were removed in the design stage. The index of hemolysis of the pump operating at more than 200 mm Hg was found to be lower than that of a commercial pump. Four‐week animal tests were then conducted two times; improvement of thrombus formation was seen in the female pivot through modification of female pivot geometry. Overall antithrombogenicity was also recorded. Finally, to assure mid‐term use, an additional 4‐week durability test revealed that the rate of the axial pivot wear was as small as 1.1 µm/day. The present in vitro and in vivo studies revealed that the MERA monopivot centrifugal pump has sufficient hemocompatibility and durability for up to 4 weeks.  相似文献   
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Retraction of ‘Effect of temperature and large guest molecules on the C–H symmetric stretching vibrational frequencies of methane in structure H and I clathrate hydrates’ by Akihiro Hachikubo et al., RSC Adv., 2018, 8, 3237–3242, DOI: 10.1039/c7ra12334e.

We, the authors, hereby wholly retract this article due to the incorrect calibration of temperature in the Raman measurements. This incorrect calibration means that the temperature values for Raman spectroscopy shown in the article were inaccurate, and the actual temperature range was higher than the range reported in the original article.Having consulted with an independent expert, the Royal Society of Chemistry has determined that any changes made to the paper to correct this would be major, and therefore that the best course of action is retraction and republication of the article with the correct data. The Royal Society of Chemistry is happy that the overall conclusions of the paper are not affected by this error, and therefore that republication of the work with the correct data is appropriate. The republished article can be found at https://doi.org/10.1039/D0RA02748K.We, the authors, brought this matter to the attention of the Royal Society of Chemistry ourselves, and are happy with the decision to retract and republish this article.Signed: Akihiro Hachikubo (on behalf of the authors)Date: 15th April 2020Retraction endorsed by Laura Fisher, Executive Editor, RSC Advances  相似文献   
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ABSTRACT

Purpose/Aim: Although several prognostic factors for extrahepatic cholangiocarcinoma (EHC) have been reported, preoperative prognostic factors have yet to be established. We investigated the serum concentration of angiogenic, inflammatory, and nutritional parameters. Materials and Methods: Twenty-five patients with EHC were enrolled before starting treatment. Preoperative prognostic factors were identified using multivariate analyses. Results: The serum soluble intercellular adhesion molecule-1 (sICAM-1) levels were significantly higher in the patients with EHC (436.0 ± 43.2 ng/ml) than in the healthy volunteers (228.6 ± 22.0 ng/ml) (p <.001). In addition, the serum IL-6 levels were significantly higher in the patients (18.0 ± 5.6 pg/ml) than in the healthy volunteers (5.7 ± 0.8 pg/ml) (p <.05). The serum IL-6 and sICAM-1 showed a strong correlation (r = 0.559) in the patients with EHC (p <.01). The serum IL-6 (area under the curve = 0.764, p =.030, cut-off level = 11.6) and sICAM-1 (area under the curve = 0.818, p =.007, cutoff level = 322.6) were revealed to be useful as prognostic factors by the receiver operating characteristic curves. The high IL-6 group and the high sICAM-1 group showed poorer DSS than those of the respective low groups. In the multivariate analysis, IL-6 (hazard ratio: 1.050, 95% confidence interval: 1.002–1.100, p =.043) and sICAM-1 (hazard ratio: 1.009, 95% confidence interval: 1.002–1.015, p =.009) were independent prognostic factors for DSS. Conclusions: IL-6 and sICAM-1 were independent preoperative prognostic factors in EHC patients, causing continuous inflammation and malnutrition in collaboration with other pro-angiogenic factors.  相似文献   
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Background

The purposes of this study were to clarify the risk factors for supraclavicular lymph node (SCLN) metastasis and the survival benefit from cervical lymph node (LN) dissections in patients with clinically submucosal (cT1b) carcinoma of the thoracic esophagus.

Methods

A total of 86 patients with this disease who underwent esophagectomy with 3-field lymph node dissection were retrospectively reviewed. Multivariate logistic regression and Cox proportional hazard model were used to identify the independent risk factors for SCLN metastasis and prognostic factors, respectively. An index calculated by multiplying the frequency of metastasis at nodal basin and the 5-year overall survival rate of patients with metastasis at that basin were used to assess the therapeutic outcomes.

Results

A total of 40 patients (47 %) were found to have pathological LN metastasis. Also, 13 patients (15 %) had cervical LN metastasis: 6 and 7 with carcinoma of the upper and mid-thoracic esophagus, respectively. SCLN metastasis was found in 6 patients (7 %); however, there was no independent risk factor for SCLN metastasis. The 5-year overall survival rate was 72.5 %. Cervical LN metastasis was an independent prognostic factor (p = .04; odds ratio 2.55; 95 % confidence interval 1.03–6.31); however, there was no significant difference in survival between patients with SCLN metastasis and those without (p = .06). The calculated index of estimated benefit from cervical LN dissections was 6.9, following upper mediastinal LN of 15.6 and perigastric LN of 8.3.

Conclusions

We could not identify risk factors to predict SCLN metastasis. Cervical LN dissection should not be omitted in patients with cT1b carcinoma, especially of the upper and mid-thoracic esophagus.  相似文献   
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We describe a new technique for the treatment of cryptotia by which stitches for bolster fixation are inserted parallel to the auriculartemporal sulcus and temporarily left untied. After the bolster has been inserted into the temporal sulcus, the corresponding ends of the threads are tied to each other. Our technique is easy to use and secures a firm bolster fixation, and we recommend it for the treatment of cryptotia.  相似文献   
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INTRODUCTIONWe present a rare case of mesenteric lymphangioma in a middle-aged female.PRESENTATION OF CASEA 56-year-old female was admitted to the hospital with upper abdominal pain. Abdominal computed tomography revealed a multicystic mass surrounding the mesentery. We made the decision to resect the mass, suspecting that was a mesenteric lymphangioma based on additional imaging studies. The tumor adhered strongly to parts of the duodenum and the upper jejunum. In order to preserve the jejunum, we dissected its serosa away from the tumor. Approximately 1 week after surgery the patient experienced a constriction of the third portion of the duodenum. Her symptoms were improved with conservative therapy, and she was discharged from the hospital 62 days after surgery.DISCUSSIONLymphangioma originating from the mesentery may have cause adhesions due to exfoliated tumor cells; it is necessary to be concerned about postoperative obstruction.CONCLUSIONThe preoperative diagnosis of lymphangioma is based on various imaging modalities.  相似文献   
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