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We have previously reported tough inorganic/organic nanocomposite (NC) ion gels composed of silica particles and poly(N,N-dimethylacrylamide) (PDMAAm) networks and a large amount of ionic liquid. In this study, the network structure and toughening mechanism of NC ion gels were investigated. The NC ion gels showed characteristic mechanical properties; i.e. the stress was significantly increased at a highly elongated state. In addition, the NC ion gels showed an almost elastic mechanical property, which was completely different from that of our other developed inorganic/organic tough ion gels named double-network (DN) ion gels. It was found from structural observation that secondary silica nanoparticles dispersed well in the NC ion gel. It was also found that some of the secondary silica nanoparticles had a ring-like structure which would incorporate PDMAAm chains. From the silica particle content dependency on stress–strain curves of inorganic/organic NC ion gels, it was inferred that the secondary silica particles could serve as a movable cross-linker of PDMAAm chains in the NC ion gel.Tough inorganic/organic nanocomposite (NC) ion gels with silica nanoparticle aggregates having a characteristic structure. 相似文献
73.
Tomonori Matsuyama Hiroshi Iranami Keisuke Fujii Mariko Inoue Reiko Nakagawa Kohei Kawashima 《Journal of anesthesia》2013,27(6):838-843
Background
Emergency surgery itself induces high risk for postoperative mortality and morbidities; however, it remains unknown which concomitant pathological conditions of emergency surgeries are causative factors of deteriorating outcomes. This study examined the causal factors of postoperative mortality and morbidity in cases of emergency surgery.Methods
Patients undergoing emergency surgery from January to December 2007 were enrolled in this retrospective cohort study. Causal relationships were analyzed by stepwise multivariate logistic regression analysis between possible independent factors (sex, age, kind of surgical department, timing of surgery, duration of surgery, blood transfusion, deteriorated consciousness level, shock state, abnormal coagulate state, and history of hypertension, diabetes, ischemic heart disease, chronic obstructive pulmonary disease, renal failure, and anemia) and postoperative mortality or morbidities (failure of removal of tracheal tube after operation, tracheotomy, cerebral infarction, massive hemorrhage, severe hypotension, severe hypoxemia, and severe arrhythmia during or after surgery).Results
Shock, deteriorated consciousness level, chronic obstructive lung disease, and ischemic heart disease were significant risk factors for mortality (OR 14.2, 7.9, 6.4, and 3.8, respectively), and deteriorated consciousness level, blood transfusion, shock, chronic obstructive lung disease, diabetes, cardiovascular surgery, and operation longer than 2 h were significant risk factors for morbidity (OR 19.1, 3.3, 3.0, 2.5, 2.4, 2.4, and 1.8, respectively).Conclusion
State of shock, deteriorated consciousness level, chronic obstructive lung disease, ischemic heart disease, hemorrhage requiring blood transfusion, age over 80 years, cardiovascular surgery, surgeries at night, and surgeries of duration more than 2 h cause patients to be strongly susceptible to postoperative mortality or morbidity in emergency surgeries. 相似文献74.
Yukihiko Hiroshima Fumio Nakamura Hiroshi Miyamoto Ryutaro Mori Koichi Taniguchi Ryusei Matsuyama Hirotoshi Akiyama Kuniya Tanaka Yasushi Ichikawa Shingo Kato Noritoshi Kobayashi Kensuke Kubota Yoji Nagashima Yoshio Goshima Itaru Endo 《Annals of surgical oncology》2013,20(3):369-378
Background
Pancreatic cancer is an aggressive malignancy with one of the worst mortality rates of all cancers. Recently, collapsin response mediator proteins (CRMPs) were reported to be associated with proliferation, apoptosis, differentiation, and invasion in several cancers. However, CRMP expression and their role in pancreatic cancer have not been investigated. This study aimed to clarify the clinical significance of CRMPs in pancreatic cancer.Methods
Expression of crmp genes in 11 pairs of pancreatic cancer and corresponding noncancerous pancreas tissues were examined by real-time RT-PCR. Knockdown of CRMP4 expression using siRNA was examined in pancreatic cancer cell lines to determine whether CRMP4 regulates cell proliferation and invasion in vitro. Furthermore, CRMP4 protein levels in primary tumors of pancreatic cancer (n = 53) were examined by immunohistochemistry and compared with the clinicopathological features of the tumors.Results
Of all the CRMPs, only CRMP4 was differentially expressed in pancreatic cancer tissues (p = 0.008). CRMP4 knockdown using siRNA reduced cellular invasion, but did not affect proliferation. The expression of CRMP4 was detected immunohistochemically in 34 (64.2 %) of the 53 pancreatic cancer samples, and CRMP4 expression was correlated with severe venous invasion (p = 0.044), stage (p = 0.019), and liver metastasis (p = 0.021). Multivariate analyses suggested that venous invasion and CRMP4 overexpression were prognostic factors for survival.Conclusions
Our results suggested that CRMP4 is significantly associated with poor prognosis by promoting liver metastasis and can serve as a novel therapeutic target for pancreatic cancer.75.
A comparison of error detection rates between the reading aloud method and the double data entry method 总被引:1,自引:0,他引:1
Kawado M Hinotsu S Matsuyama Y Yamaguchi T Hashimoto S Ohashi Y 《Controlled clinical trials》2003,24(5):560-569
Data entry and its verification are important steps in the process of data management in clinical studies. In Japan, a kind of visual comparison called the reading aloud (RA) method is often used as an alternative to or in addition to the double data entry (DDE) method. In a typical RA method, one operator reads previously keyed data aloud while looking at a printed sheet or computer screen, and another operator compares the voice with the corresponding data recorded on case report forms (CRFs) to confirm whether the data are the same. We compared the efficiency of the RA method with that of the DDE method in the data management system of the Japanese Registry of Renal Transplantation. Efficiency was evaluated in terms of error detection rate and expended time. Five hundred sixty CRFs were randomly allocated to two operators for single data entry. Two types of DDE and RA methods were performed. Single data entry errors were detected in 358 of 104,720 fields (per-field error rate=0.34%). Error detection rates were 88.3% for the DDE method performed by a different operator, 69.0% for the DDE method performed by the same operator, 59.5% for the RA method performed by a different operator, and 39.9% for the RA method performed by the same operator. The differences in these rates were significant (p<0.001) between the two verification methods as well as between the types of operator (same or different). The total expended times were 74.8 hours for the DDE method and 57.9 hours for the RA method. These results suggest that in detecting errors of single data entry, the RA method is inferior to the DDE method, while its time cost is lower. 相似文献
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79.
Hanada Mitsuru Hotta Kensuke Furuhashi Hiroki Matsuyama Yukihiro 《European journal of orthopaedic surgery & traumatology : orthopedie traumatologie》2020,30(5):917-921
European Journal of Orthopaedic Surgery & Traumatology - Surgical site infection (SSI) and periprosthetic joint infection are the most important problems after total hip arthroplasty (THA) and... 相似文献
80.
Norihito Ogawa Hideaki Iseki Hidefumi Tsunozaki Mikiko Hayashi Hironobu Baba Takatoshi Matsuyama Hiroyuki Uetake Kenichi Sugihara 《Surgery today》2014,44(11):2174-2179
Desmoid tumors are benign fibroblastic neoplasms with no metastatic potential, but a propensity for local recurrence even after complete surgical resection. These lesions can develop at any site in the body, and commonly occur in the intra-abdominal area. Intra-abdominal desmoid tumors usually occur at the mesentery or retroperitoneum, and may morphologically mimic gastrointestinal stromal tumors (GISTs). Distinguishing between these tumors is important, because the therapies differ substantially, but is often difficult even with the use of CD117 staining. We herein report the cases of two patients with sporadic intra-abdominal desmoid tumors that were differentiated from GIST by immunohistological examination using beta-catenin and CD34. Desmoid tumors specifically express nuclear beta-catenin, and show no expression of CD34. We recommend staining for beta-catenin and CD34 when an intra-abdominal desmoid tumor is suspected. 相似文献