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61.
62.
Takahiro Shuto Yuichi Mine Seicho Makihira Hiroki Nikawa Takanori Wachi Kazutoshi Kakimoto 《Materials》2022,15(1)
Fluoride and abrasives in toothpastes may cause corrosion and deterioration of the titanium used for implants and other prostheses. The purpose of this study was to investigate how the presence or absence and types of fluoride and abrasives affected the titanium surface texture. Brushing with toothpastes was performed on pure-titanium discs using an abrasive testing machine. Unprocessed titanium discs without brushing were used as control samples. Surface roughness, color, and gloss of titanium were measured and the differences compared with the control were analyzed. Additionally, titanium surfaces and abrasives in toothpastes were observed using a scanning electron microscope to compare the surface texture of each sample. Some toothpastes (abrasive+) significantly increased the difference in surface roughness, color, and gloss, compared with ultrapure water. Toothpaste (fluoride+/abrasive+) that had many polygonal abrasive particles led to the largest color differences and exhibited notable scratches and a larger number of contaminant- or corrosion-like black spots. In contrast, brushing with toothpaste without fluoride or abrasives (fluoride−/abrasive−) caused little change to the titanium surface. These results suggest that both fluoride and abrasives in toothpaste used for brushing may be factors that affect surface texture and corrosion resistance of titanium. 相似文献
63.
Kazutoshi Ono Yoshiyuki Yamanaga Kyousuke Yamamoto Shun-Ichi Koga Junji Nishimura Hajime Nawata 《Journal of clinical immunology》1996,16(1):41-45
Previously we proposed a new analysis of natural killing activity, for comparison, employing an individual effector/ target cell ratio according to the peripheral number of effector cells. Using this analysis, we studied natural killing activities in chronic liver diseases and hepatocellular carcinoma (HCC). The activity in chronic persistent hepatitis remained nearly at the level of the nonactivated state, but that was significantly elevated in chronic active hepatitis. The activity in liver cirrhosis (LC) of Child's A or B grade was at the level of a nonactivated or reduced-activity state, while LC patients with impaired general conditions showed significantly elevated activities. In HCC, each of which was accompanied by LC in our cases, the activity appeared to be associated with the progression of HCC. Thus, natural killing activity showed a close relationship with the condition of chronic liver diseases. 相似文献
64.
Yoshihiro Saito Sumitaka Kobayashi Atsuko IkedaAraki Sachiko Ito Chihiro Miyashita Takashi Kimura Takumi Hirata Akiko Tamakoshi Michinori Mayama Kiwamu Noshiro Kinuko Nakagawa Takeshi Umazume Kentaro Chiba Satoshi Kawaguchi Mamoru Morikawa Kazutoshi Cho Hidemichi Watari Yoshiya Ito Yasuaki Saijo Reiko Kishi the Japan Environment Children's Study group 《Journal of diabetes investigation.》2022,13(5):889
Aims/IntroductionWe investigated the association between gestational diabetes mellitus (GDM) and perinatal outcomes stratified by pre‐pregnancy body mass index (BMI) and/or gestational weight gain (GWG).Materials and MethodsData from the national birth cohort in the Japan Environment and Children''s Study from 2011 to 2014 (n = 85,228) were used. Japan uses the GDM guidelines of the International Association of Diabetes and Pregnancy Study Groups. The odds ratios (ORs) of perinatal outcomes were compared between women with and those without GDM.ResultsThe OR (95% confidence interval) of having a small for gestational age infant in the GDM group with a pre‐pregnancy BMI of ≥25.0 kg/m2 and insufficient GWG (<2.75 kg) was 1.78 (1.02–3.12). The OR of having a large for gestational age infant of the same BMI group with excessive GWG (>7.25 kg) was 2.04 (1.56–2.67). The OR of hypertensive disorders of pregnancy was higher in women with a BMI ≥18.5 kg/m2 in the GDM group than in the non‐GDM group.ConclusionsLarge for gestational age and hypertensive disorders of pregnancy were associated with pre‐pregnancy BMI and GWG in either normal weight or overweight/obese women, and the relationship was strengthened when GDM was present. Women with GDM and a BMI of ≥25.0 kg/m2 are at risk of having small for gestational age and large for gestational age infants depending on GWG. 相似文献
65.
Mimatsu K Oida T Kawasaki A Kano H Fukino N Kida K Kuboi Y Amano S 《Surgery today》2011,41(10):1410-1413
MUC1 expression in cholangiocarcinoma is considered to be correlated with patient survival. We report a case of mass-forming
type intrahepatic cholangiocarcinoma (ICC) with direct infiltration of the transverse colon and sequential brain metastasis.
The patient was treated by curative right hepatectomy with right hemicolectomy followed by resection of the brain metastasis;
there has been no evidence of recurrence in the 7 years since the hepatic resection. Thus, surgical resection may improve
the prognosis of ICC involving the adjacent organs, even with brain metastasis. Immunohistochemical staining was performed
for MUC1, MUC2, and MUC5AC. Although MUC1 expression was found in the liver tumor and metastatic brain tumor, the correlation
between MUC1 expression and the prognosis of this patient was unclear. To clarify the correlation between immunohistochemical
characteristics and prognosis, further studies on a greater number of cases of long-term survival of mass-forming type ICC
are needed. 相似文献
66.
67.
68.
Keiko Onda Kazutoshi Iijima Yohko U. Katagiri Hajime Okita Masahiro Saito Toshiaki Shimizu Nobutaka Kiyokawa 《International journal of hematology》2010,91(5):808-819
B cell-activating factor belonging to the tumor necrosis factor superfamily (BAFF) is a crucial factor for B cell development
and is involved in the survival of malignant B cells, but its effect on B cell precursors (BCPs) remains unclear. We investigated
BCP acute lymphoblastic leukemia (-ALL) cells for BAFF receptor (-R) expression and compared the effect of BAFF on BCP-ALL
cells and Burkitt lymphoma (BL) cells. Expression of BAFF-R was detected in some cell lines and some clinical specimens of
both BL and BCP-ALL. BAFF acted on both BL and BCP-ALL cells and promoted proliferation by both. BAFF also inhibited apoptosis
by BL cells induced by cross-linking of cell surface molecules and anticancer drugs, but failed to inhibit apoptosis by BCP-ALL
cells. BAFF induced prompt and obvious activation of the NF-κB signaling pathway in BL cells, but only weak and delayed activation
of the pathway in BCP-ALL cells. The results of this study indicate that some BCP-ALL cells and some BL cells express BAFF-R,
but that the effects of BAFF on BCP-ALL cells are different from its effects on mature B cell malignancies. 相似文献
69.
70.
Dai Nakae Yasushi Mizumoto Hitoshi Yoshiji Nobuaki Andoh Kohsuke Horiguchi Kazumi Shiraiwa Eisaku Kobayashi Takehiro Endoh Naoshi Shimoji Kazutoshi Tamura Toshifumi Tsujiuchi Ayumi Denda Yoichi Konishi 《Cancer science》1994,85(5):499-505
The present study was performed to assess the roles of hepatocellular oxidative damage to DNA and constituents other than DNA in rat liver carcinogenesis caused by a choline-deficient, l -amino acid-defined (CDAA) diet by examining the effects of the antioxidant N, N' -diphenyl- p -phenylenediamine (DPPD). The parameters used for cellular oxidative damage were the level of 8-hydroxyguanine (8-OHGua) for DNA and that of 2-thiobarbituric acid-reacting substance (TBARS) for constituents other than DNA. A total of 40 male Fischer 344 rats, 6 weeks old, were fed the CDAA diet for 12 weeks with or without DPPD (0.05, 0.10 or 0.20%) or butylated hydroxytoluene (BHT, 0.25%). In the livers of the rats, the numbers and sizes of glutathione S -transferasc (EC 2.5.1.18) placental form (GSTP)- and/or γ-glutamyltransferase (GGT, EC 2.3.2.2)-positive lesions and levels of 8-OHGua and TBARS were determined. The GSTP-positive lesions of 0.08 mm2 or larger were all stained positively for GGT as well in cross-sectional area, whereas the smaller lesions were generally negative for GGT. DPPD and BHT reduced the size of the GSTP-positive lesions without affecting their total numbers. At the same time, they reduced TBARS generation without affecting 8-OHGua formation in DNA. The present results indicate that oxidative DNA damage (represented by 8-OHGua formation) and damage to constituents other than DNA (represented by TBARS generation) may play different roles in rat liver carcinogenesis caused by the CDAA diet; the former appears to be involved in the induction of phenotypically altered hepatocyte populations while the latter may be related to the growth of such populations. 相似文献