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51.
Colloidal crystals (CCs) are periodic arrays of monodisperse microparticles. Such CCs are very attractive as they can be potentially applicable as versatile photonic devices such as reflective displays, sensors, lasers, and so forth. In this article, we describe a promising methodology for synthesizing monodisperse magnetite microparticles whose diameters are controllable in the range of 100–200 nm only by adjusting the base concentration of the reaction solution. Moreover, monodisperse magnetite microparticles in aqueous suspensions spontaneously form the CC structures under an external magnetic field, leading to the appearance of Bragg reflection colors. The reflection peak can be blue-shifted from 730 nm to 570 nm by the increase in the external magnetic field from 28 mT to 220 mT. Moreover, the reflection properties of CCs in suspension depend on the microparticle concentration in suspension and the diameter of the magnetite microparticles. Both fine-control of microparticle diameter and investigation of magneto-optical properties of CCs would contribute to the technological developments in full-color reflective displays and sensors by utilizing these monodisperse magnetite microparticles.  相似文献   
52.
Background  Risk factors of surgical site infection (SSI) after hepatectomy under the guideline of Centers for Disease Control and Prevention (CDC) are not well examined. Methods  Hospital records of consecutive patients who underwent hepatectomy without biliary reconstruction for liver cancers were reviewed retrospectively. Prophylactic antibiotics were given to patients just before skin incision and every 3 hours during the operations. Clinicopathological factors were compared between patients who developed SSI and those without it. Results  There were 405 patients identified, and the incidence of SSI was 23 cases (5.8%). In multivariate analysis, intraoperative bowel injury, blood loss >2000 ml, and age older than 65 years were significant risk factors of SSI after hepatectomy. Conclusions  Prophylactic antibiotics were necessary only during the operation for most patients who underwent hepatectomy without biliary reconstruction. However, patients with intraoperative bowel injury, blood loss >2000 ml, and age older than 65 years are at risk to develop SSI and might need additional administration of prophylactic antibiotics after surgery.  相似文献   
53.
Background  Some studies have found high incidences of intraoperative and postoperative complications for patients with gastric cancer. To determine the predictive factors for the surgical complications of laparoscopic gastric surgery, surgical outcomes were evaluated. Methods  Between April 2002 and December 2007, 152 patients with preoperatively diagnosed early gastric cancer who underwent laparoscopy-assisted distal gastrectomy (LADG) were enrolled. Visceral (VFA) and subcutaneous fat areas (SFA) were assessed by Fat Scan software. The predictive factors for surgical complications of LADG were evaluated by univariate and logistic regression analyses. Results  Of 152 patients, conversion to open surgery due to uncontrollable bleeding was observed in nine male patients, and postoperative complications were detected in seven male and one female patient (four anastomotic leakage, two intraabdominal abscess, one pancreatic fistula, and one lymphorrhea). High body mass index (BMI) and high VFA independently predicted conversion to open surgery and postoperative complications. VFA was significantly higher, operation time was longer, blood loss was greater, and SFA was lower in male than in female patients, whereas no significant difference was observed in BMI between male and female patients. Conclusions  High BMI and high VFA can predict technical difficulties during laparoscopic gastric surgery and postoperative complications. Particularly, LADG should be performed cautiously to prevent surgical complications for male patients with high VFA. Predictive impact of VFA should be further determined in a larger set of patients.  相似文献   
54.
BackgroundStudies on the clinical outcomes of radiotherapy for clinical (c)T1aN0M0 (UICC-TNM Classification, Eighth Edition) esophageal cancer (EC) are limited. Therefore, this retrospective study aimed to clarify the clinical outcomes of definitive radiotherapy (RT) or chemoradiotherapy (CRT) for cT1aN0M0 EC unsuitable for endoscopic resection and surgery.MethodsPatients with cT1aN0M0 esophageal squamous cell carcinoma who underwent definitive RT or CRT between January 2009 and December 2020 were retrospectively reviewed. The initial response, toxicities, survival rates, recurrence patterns, and salvage treatments of the patients were evaluated. Initial response was measured using the Response Evaluation Criteria in Solid Tumors guideline. Toxicity was assessed and documented following the National Cancer Institute Common Terminology Criteria for Adverse Events (CTCAE) version 5.0. Survival rates from the date of initiation of treatment were measured using the Kaplan–Meier method.ResultsTwenty patients treated with definitive RT or CRT were included in the study. The median follow-up duration was 55 months (range, 13–131 months). All patients achieved complete response to the initial treatment. Grade 3 acute toxicities observed esophagitis (10%), pneumonitis (5%), and leukopenia (5%). Late toxicities higher than grade 3 were not observed. The 1-, 3-, and 5-year overall and disease-specific survival rates were 100% and 100%, 83% and 100%, and 67% and 100%, respectively. No treatment-related deaths occurred. Among the 20 patients, 6 showed local recurrence and 2 showed metachronous recurrence. Seven patients underwent salvage endoscopic submucosal dissection (ESD), and one underwent argon plasma coagulation treatment. After the endoscopic treatment, no recurrences were observed.ConclusionsDefinitive RT or CRT was considered an alternative initial treatment for patients with cT1aN0M0 EC who were unsuitable for endoscopic resection and surgery.  相似文献   
55.
Background

Downstream activation through receptor tyrosine kinases (RTKs) plays important roles in carcinogenesis. In this study, we assessed the clinical involvement of Axl, an RTK, and its ligand, Gas6, in surgically treated lung adenocarcinoma.

Methods

Axl and Gas6 mRNA and protein expression levels were quantified using quantitative real-time polymerase chain reaction and immunohistochemistry, respectively, in completely resected lung adenocarcinoma tissues (n = 88) and were evaluated for correlation with clinicopathologic features and patient survival.

Results

Higher expressions of Axl mRNA/protein and Gas6 protein were significantly related to worse clinicopathological features and prognosis (5-year overall survival rates: Axl mRNA low: 72.3 %, high: 49.7 %, P = 0.047; Axl protein low: 77.5 %, high: 38.6 %, P < 0.001; and Gas6 protein low: 70.5 %, high: 48 %, P = 0.042). On the contrary, higher Gas6 mRNA expression was related to better clinicopathological features and prognosis (5-year overall survival rates: Gas6 mRNA low: 59.2 %, high: 81.8 %, P = 0.054). Multivariate analysis suggests that high Axl mRNA expression may be an independent factor for poor patient prognosis (P = 0.04).

Conclusions

In lung adenocarcinoma, Axl and Gas6 expression levels were associated with tumor advancement and patient survival, thus rendering them as reliable biomarkers and potential targets for treatment of lung adenocarcinoma.

  相似文献   
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The aim of this paper was to explain the insurance coverage status of therapeutic apheresis (excluding CHDF) in Japan, alongside the social system of medical reimbursement and concerns regarding the future sustainability of the healthcare system. Insurance schemes and premiums differed for individuals at different levels in the society (eg, municipal residents, employees, and public servants). Insurance premiums and their rates varied depending on the total household income, the number of people living together, age, and the place of residence. In addition, the medical expense subsidies for children through public expenditure were also described. Japan's generous insurance system and multiple medical expense subsidies provide financial support for patients. With Japan's history of medical expense subsidies based on the policy of supporting intractable diseases, we have established an environment where all citizens can receive therapeutic apheresis when needed if they are affected by a disease for which insurance coverage is indicated.  相似文献   
59.

Objective

For patients with end-stage renal disease on hemodialysis, the durability of vascular access (VA) is still far from optimal, and access survival after intervention for access failure is an important aspect. Procoagulant status is a leading cause of access failure. Coagulation-fibrinolysis imbalance can occur in hemodialyzed patients, but the influence of the imbalance has not been fully elucidated.

Methods

We prospectively examined coagulation-fibrinolysis balance to assess the risk of access failure after the intervention of revascularization in a cohort of 462 hemodialysis patients. Thrombin-antithrombin complex (TAT) and plasmin-α2-plasmin inhibitor complex (PIC) are markers for coagulation and fibrinolysis. Median follow-up was 243 days. The end point was clinical access failure: revascularization or access revision. The survival curve for VA patency was assessed using the Kaplan-Meier method and compared using the log-rank test. Cox proportional hazards regression models that allowed adjustment for baseline differences in age, sex, dialysis vintage, diabetes mellitus, and various factors (quantity of blood flow, prothrombin time-international normalized ratio, fibrin degradation products, C-reactive protein, interleukin-6, tumor necrosis factor-α, and pentraxin-3) were used.

Results

The 162 patients who reached an end point had smaller access flow volume and smaller percentage of arteriovenous fistula and higher TAT/PIC ratio. Kaplan-Meier analysis indicated that the patients with elevated TAT/PIC ratio showed poorer outcome (P < .001). On Cox regression modeling, elevated TAT/PIC was an independent risk factor for access failure (hazard ratio, 1.58; P = .03).

Conclusions

Our results suggest that coagulation-fibrinolysis imbalance is a significant risk factor for access failure and may predict VA failure in hemodialyzed patients after access intervention.  相似文献   
60.
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