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121.
To produce water-stable Ni-rich lithium nickel cobalt aluminum oxides (LiNixCoyAl1−xyO2, x > 0.85, NCAs), the formation of trilithium phosphate (Li3PO4)-coated layers on the NCA surfaces was attempted through the use of a surface reaction in a mixture of ethanol and water and a post-heat treatment at 350 and 400 °C. Based on the results of X-ray photoelectron spectroscopy (XPS), the coated layers consisted of nickel phosphate (Ni3(PO4)2) and Li3PO4. The coated NCA surface could have sufficient water stability to maintain the cathode performance in a water slurry for 1 day. In addition, the coated layers formed on the NCA surfaces did not block Li+-ion transfer through the Ni3(PO4)2/Li3PO4-coating layers and enhanced the high-rate discharge performance.

To produce water-stable Ni-rich lithium nickel cobalt aluminum oxides, the formation of trilithium phosphate coated layers on the NCA surfaces was attempted through the use of a surface reaction in a mixture of ethanol and water and a post-heat treatment at 350 and 400 °C.  相似文献   
122.
Journal of Neurology - Poststroke epilepsy is a common problem in clinical practice. This study aimed to determine the predictors of poststroke epilepsy and to identify the risk factors. A total of...  相似文献   
123.
The crush stent technique has recently been proposed to limit the development of restenosis between drug-eluting stents implanted at coronary artery bifurcations. We studied the stent expansion, apposition to the vessel, and aspect of the overlapping stents after in vivo crush stent implantation. Crush stent implantation was performed at coronary bifurcations in anesthetized swines. The treated sites were examined using intravascular ultrasound and a vascular endoscope. The stents removed from the vessel were analyzed macroscopically. After final kissing balloon inflation, an adequate apposition of the stent to the vessel wall was confirmed by vascular endoscopy and visual inspection. However, the side-branch stent was narrowed at the site of stent overlap, and the overlapping stents in the main branch created a metal mass, which could promote the development of thrombosis. The technique of crush stent implantation with additional kissing balloon inflation is feasible and promising. However, it may be limited by thrombosis and restenosis at the carina because of stent overlapping and potential incomplete apposition. Additional studies are needed to confirm the safety and long-term clinical results of this technique.  相似文献   
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125.
Hodgkin's lymphoma (HL) is in general a lymph node‐based disease. Hepatic involvement usually occurs in the advanced disease. Primary and prominent manifestation of the disease in the liver is extremely rare. We report magnetic resonance imaging leading to diagnosis in a rare case of liver involvement as the first sign of HL.  相似文献   
126.
Increasing recipient age is a well-known risk factor for graft-versus-host disease (GVHD) and treatment-related mortality (TRM) and has a negative impact on allogeneic hematopoietic stem cell transplantation. Since the incidence of severe GVHD after cord blood transplantation (CBT) is lower than that after transplants using bone marrow or mobilized peripheral blood grafts from adult cells, we should expect better outcomes from CBT in older patients. To evaluate the feasibility and efficacy of myeloablative unrelated CBT in patients aged between 50 and 55 years, we performed a retrospective comparison of 100 patients with acute leukemia who received cord blood grafts at our institution. Nineteen older patients (median age, 52; range, 50–55) and 81 younger patients (median, 36; range, 16–49) received a myeloablative conditioning regimen including 12 Gy of total body irradiation and chemotherapy. GVHD prophylaxis included cyclosporine with (n = 96) or without (n = 4) methotrexate. There were no significant differences in the incidences of grades II to IV acute GVHD, extensive-type chronic GVHD, TRM, and the probability of overall and disease-free survival between these groups. These results suggest that, in patients with acute leukemia, myeloablative CBT might be as safe and effective in patients aged between 50 and 55 years as in younger patients.  相似文献   
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128.
Thymocyte negative selection eliminates self-reactive clones and involves both a T-cell receptor (TCR)/CD3-mediated signal and a costimulatory signal, which can be delivered via CD28. Anti-CD3/anti-CD28-triggered apoptosis in isolated CD4+CD8+ thymocytes in vitro provides a basic model for negative selection. Effects of isoform-selective and non-isoform-selective inhibitors of protein kinase C (PKC) on this apoptotic process suggest that activation of Ca2+-independent PKC isoforms during the first 2-3 hr of culture is essential for inducing apoptosis, and that Ca2+-dependent PKC isoforms may be influential, but not essential, for apoptosis. To assess the CD3/CD28-mediated activation of PKC in the apoptotic process, we prepared CD4+CD8+ thymocytes (without contamination with cells that had received negative or positive selection signals in vivo) by establishing TCR-transgenic mice with RAG-2-deficient and non-selecting major histocompatibility complex (MHC) backgrounds, in addition to a CD4+CD8+ thymocyte-enriched population from normal mice. Translocation of Ca2+-independent PKC from the cytosolic fraction to the particulate fraction of CD4+CD8+ thymocytes was induced by CD3/CD28-mediated stimulation, but not by CD3- or CD28-mediated stimulation alone, and peaked 2 hr after the start of culture. The kinase activity of the translocated Ca2+-independent PKC was dependent on cofactors in vitro, indicating that novel (n)PKC, but not atypical (a)PKC or a proteolytic PKC fragment, was responsible for the activity. Immunoblotting analysis indicated that the nPKC-theta isoform was the major contributor among nPKC isoforms, and that the classical (c)PKC-alpha isoform was the major contributor among cPKC isoforms. These results suggest that activation of nPKC (especially the theta isoform) in CD4+CD8+ thymocytes is involved in a pathway for negative selection.  相似文献   
129.
Gastric carcinoma is relatively rare in patients under the age of 40. This study was undertaken to clarify the clinicopathological characteristics and surgical outcomes of gastric carcinoma in younger patients compared with those of middle-aged patients. The surgical results from 131 younger patients (aged ⩽40 years) and 918 middle-aged patients (aged 55–65 years) were compared retrospectively. Female gender, undifferentiated tumor type and lymphatic invasion were significantly more common in the younger patients. Survival time did not differ between the two groups. The depth of tumor invasion was the only prognostic factor in younger patients, whereas macroscopic appearance, tumor diameter, depth of invasion, lymph node metastasis, and venous invasion were all significant prognostic factors in middle-aged patients. Peritoneal recurrence was significantly more common in younger patients. A family history of gastric adenocarcinoma was observed in 25.9% of younger patients, but this did not affect survival outcomes. As depth of invasion affects prognosis independently, and peritoneal metastasis is the predominant pattern of recurrence, it is essential to establish an optimal prophylactic treatment for peritoneal metastasis to improve surgical outcomes in younger patients with advanced gastric cancer.  相似文献   
130.
Diagnostic and therapeutic strategies for acute biliary inflammation/infection (acute cholangitis and acute cholecystitis), according to severity grade, have not yet been established in the world. Therefore we formulated flowcharts for the management of acute biliary inflammation/infection in accordance with severity grade. For mild (grade I) acute cholangitis, medical treatment may be sufficient/appropriate. For moderate (grade II) acute cholangitis, early biliary drainage should be performed. For severe (grade III) acute cholangitis, appropriate organ support such as ventilatory/circulatory management is required. After hemodynamic stabilization is achieved, urgent endoscopic or percutaneous transhepatic biliary drainage should be performed. For patients with acute cholangitis of any grade of severity, treatment for the underlying etiology, including endoscopic, percutaneous, or surgical treatment should be performed after the patient's general condition has improved. For patients with mild (grade I) cholecystitis, early laparoscopic cholecystectomy is the preferred treatment. For patients with moderate (grade II) acute cholecystitis, early laparoscopic or open cholecystectomy is preferred. In patients with extensive local inflammation, elective cholecystectomy is recommended after initial management with percutaneous gallbladder drainage and/or cholecystostomy. For the patient with severe (grade III) acute cholecystitis, multiorgan support is a critical part of management. Biliary peritonitis due to perforation of the gallbladder is an indication for urgent cholecystectomy and/or drainage. Delayed elective cholecystectomy may be performed after initial treatment with gallbladder drainage and improvement of the patient's general medical condition.  相似文献   
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