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31.
BACKGROUND AND AIMS: Preoperative estimation of depth of invasion in early colorectal cancers (CRCs) is essential for patient management. This study was conducted to compare the diagnostic accuracies of magnifying colonoscopy and endoscopic ultrasonography (EUS) for estimating the depth of invasion of early CRCs. SUBJECTS AND METHODS: A total of 438 early CRCs were removed endoscopically or surgically from July 1993 through March 1999 at our hospital. Before removal, 102 lesions were evaluated with both magnifying colonoscopy and EUS and were included in this analysis. The diagnostic accuracy of each method, referring to the histology of the resected specimens, was evaluated. RESULTS: The overall diagnostic accuracies were 87% (89/102) for magnifying colonoscopy and 75% (76/102) for EUS (P = 0.0985). Subgroup analysis was also done for polypoid and non-polypoid lesions. For polypoid lesions, the overall diagnostic accuracies of magnifying colonoscopy and EUS were 88% (60/68) and 72% (49/68), (P = 0.0785), and for non-polypoid lesions, they were 85% (29/34) and 79% (27/34), (P = 0.7169). CONCLUSION: Although, there is a substantial difference in the overall diagnostic accuracies, it is not statistically significant. Therefore, we conclude that magnifying colonoscopy is at least as accurate as EUS for preoperative staging of early CRCs.  相似文献   
32.
Oral and Maxillofacial Surgery - Medication-related osteonecrosis of the jaw (MRONJ) is an uncommon adverse drug reaction that can be induced by certain therapeutic drugs, including antiresorptive...  相似文献   
33.
Retraction: The above article in Genes to Cells (doi: 10.1111/j.1365‐2443.2007.01131.x ), published online on 2 November 2007 in Wiley Online Library ( http://onlinelibrary.wiley.com/ ), has been retracted by agreement between the authors, the journal Editor in Chief, Mitsuhiro Yanagida, and Wiley Publishing Asia Pty Ltd. The retraction has been agreed to due to lack of the gel images for the lanes 1, 2, 5, 6, 9 and 10 of ‘GR’ and lanes 1, 2, 9 and 10 of ‘Brg‐1’ in Figure 3(D) and the multiple usage of the gel images in Figure 3(B) and (C).  相似文献   
34.
35.
Fridovich identified CuZnSOD in 1969 and manganese superoxide dismutase (MnSOD) in 1973, and proposed ”the Superoxide Theory,” which postulates that superoxide (O2•−) is the origin of most reactive oxygen species (ROS) and that it undergoes a chain reaction in a cell, playing a central role in the ROS producing system. Increased oxidative stress on an organism causes damage to cells, the smallest constituent unit of an organism, which can lead to the onset of a variety of chronic diseases, such as Alzheimer’s, Parkinson’s, amyotrophic lateral sclerosis and other neurological diseases caused by abnormalities in biological defenses or increased intracellular reactive oxygen levels. Oxidative stress also plays a role in aging. Antioxidant systems, including non-enzyme low-molecular-weight antioxidants (such as, vitamins A, C and E, polyphenols, glutathione, and coenzyme Q10) and antioxidant enzymes, fight against oxidants in cells. Superoxide is considered to be a major factor in oxidant toxicity, and mitochondrial MnSOD enzymes constitute an essential defense against superoxide. Mitochondria are the major source of superoxide. The reaction of superoxide generated from mitochondria with nitric oxide is faster than SOD catalyzed reaction, and produces peroxynitrite. Thus, based on research conducted after Fridovich’s seminal studies, we now propose a modified superoxide theory; i.e., superoxide is the origin of reactive oxygen and nitrogen species (RONS) and, as such, causes various redox related diseases and aging.  相似文献   
36.
CD40 ligand (CD40L) is expressed not only on activated T cells but also on activated platelets. A soluble CD40 ligand (sCD40L) is released from the activated T cells and platelets by ill-defined proteolytic process in vitro. It has been reported that sCD40L is elevated in the serum of patients with systemic lupus erythematosus, unstable angina, essential thrombocythemia, and autoimmune thrombocytopenic purupura. However, source of sCD40L in vivo remains to be elucidated. We investigated the serial sCD40L in the serum in patients undergoing allogeneic stem cell transplantation and compared with the platelets number and soluble IL2R, which is a marker of activated T cells. The value of sCD40L was well correlated with platelet number or thrombopoiesis. In cases of severe graft vs. host disease with markedly increased sIL2R, sCD40L was not increased in vivo. These results indicate that sCD40L in vivo is released mainly from the platelets or in the process of platelet production but not from the activated T cells.  相似文献   
37.
Methotrexate (MTX) is the first-choice drug for rheumatoid arthritis (RA); however, the pharmacodynamics of MTX in Japanese patients with RA treated legitimately according to the government recommended dosage, 6 mg per week, are unknown. Methotrexate and its metabolite, 7-hydroxy MTX (7-OH MTX), were measured in sera of 16 outpatients with active RA in the first week of MTX treatment and 4–12 weeks after the introduction at 0, 1, 2, 4, and 8 h after administration of the first and the third 2-mg capsule, followed by sampling at 48, 96, and 168 h. The mean maximal serum drug concentration (mean Cmax) of MTX attained at 1–2 h after ingestion of the first capsule was 0.215 and 0.252 μM, respectively, in the first and the follow-up week. The mean Cmax after ingestion of the third capsule was 0.223 μM and 0.357 μM. The mean Cmax of 7-OH MTX was 0.0334 and 0.0289 μM for the first capsule, and 0.0495 and 0.0672 μM for the third capsule. The results indicate that MTX does not accumulate or deposit in the body of Japanese patients with RA when treated with 6 mg per week, and pharmacodynamics of MTX are comparable to those in overseas patients treated with 7.5 mg per week.  相似文献   
38.
We investigated the role that CD40-CD40 ligand (CD40L) signaling plays in survival of Epstein-Barr virus (EBV)-infected T and NK cells. EBV-infected T and NK cell lines derived from patients with either chronic active EBV infection (CAEBV) or nasal T/NK cell lymphoma, as well as virus-infected peripheral T cells freshly isolated from a patient with CAEBV, were shown to express both CD40 and CD40L on their surface. Apoptosis of these cells was enhanced by blockade of CD40-CD40L signaling by a fusion protein of CD40 and immunoglobulin G (CD40Ig). Expression of CD40 was induced in human CD40L-positive Jurkat T cells after experimental EBV infection, and apoptosis of infected cells was enhanced by CD40Ig. These results suggest that CD40-CD40L signaling promotes survival of EBV-infected T and NK cells and, thus, plays an important role in the pathogenesis of T/NK lymphoproliferative disorders associated with the virus.  相似文献   
39.
This study attempts to address an important clinical issue by identifying potential candidates of VEGF signaling through Flt-1 receptor that trigger angiogenic signal under ischemic stress. To determine the significance of VEGF-Flt-1 (VEGFR1) signaling in ischemic preconditioned (PC) myocardium, we used heterozygous Flt-1 knockout (KO) mice to dissect the pathway and identify candidate genes involved in VEGF signaling. DNA microarrays were employed to detect, characterize and distinguish altered myocardial gene expression by comparing between wild type (WT) CD-1 and heterozygous Flt-1 KO mice when exposed to ischemia (30 min) and reperfusion (2 h). Moreover, KO mice demonstrated reduced beneficial effects of PC when compared to the WT with PC. In the KO and WT mice, the % recovery of the left ventricular developed pressure and the maximum first derivative of the developed pressure after ischemia/reperfusion without PC were similar. However, when animals were subjected to PC, the left ventricular functional recovery throughout the reperfusion period was significantly lower in KO mice than in WT mice. These results indicate for the first time that in the heterozygous Flt-1 KO mice, PC is not as effective as that found in WT. This observation may be due to downregulation of several important genes such as growth-regulated oncogene 1 (Gro1), heat shock proteins (HSP), I kappa B kinase beta (IKK beta), colony-stimulating factor-1 (CSF-1) and annexin A7, suggesting the importance of VEGF-Flt-1 receptor signaling during PC.  相似文献   
40.
International Journal of Paediatric Dentistry 2012; 22: 265–270 Background. A device based on infrared laser fluorescence (IRLF) has become available as an adjunct for the diagnosis of dental caries. Aims. The objective of this study was to clarify the differences of IRLF readings in the mesial, central and distal occlusal pits of first permanent molars. Design. Sixty‐four children (average age 8.0 years) were examined using IRLF. The mesial, central and distal pits of clinically healthy first permanent molars were measured. The instrument provides measurements in arbitrary units on an open‐ended interval scale. Results. Mean (± SE) IRLF values in the mesial pits were 4.9 ± 0.4 (upper) and 6.5 ± 0.4 (lower) and were significantly lower than those in the central (8.8 ± 0.6 and 11.5 ± 0.9) and distal (9.6 ± 0.7 and 10.4 ± 0.8) pits in the maxilla and mandible. There was no significant difference between the right (7.3 ± 0.5, 9.4 ± 0.6) and left (8.2 ± 0.5, 9.5 ± 0.6) dental arches. IRLF measurements in the mesial pits of human first permanent sound molars were lower than the central and distal pits in children whose second molars had not erupted. Conclusions. The inherently higher IRLF values of some sites should not be misinterpreted and trigger early invasive treatment.  相似文献   
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