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131.
Biodegradable gelatin sponges incorporating various amounts of magnesium calcium phosphate (MCP) were introduced and the in vitro osteogenic differentiation of rat bone marrow mesenchymal stem cells (MSCs) in the sponges was investigated. The MCP was added to the gelatin sponges at 0, 25, 50, 75, and 90 wt%. The pore sizes of the gelatin sponges ranged from 143 to 154.3 μm in diameter and the porosity percentage was 34.3-50.1%. The compression modulus of the sponges and the resistance to the volume change significantly increased with increases in the amount of MCP. When seeded into the sponges by an agitating method, MSCs were distributed throughout the sponges. Following the incubation of MSCs in the gelatin sponges, a significantly higher cellular proliferation and alkaline phosphatase activity was observed in the gelatin sponges incorporating higher MCP contents. On the other hand, the osteocalcin content of MSCs seeded in the gelatin sponges incorporating no or low MCP showed a significantly higher levels in comparison with the MSCs seeded in the gelatins incorporating high MCP. These findings indicate that the MCP incorporation maintained the pore size and porosity percentage of the gelatin sponges and enabled the sponge to achieve mechanical reinforcement as well as promoting MSC proliferation and osteogenic differentiation. 相似文献
132.
Niimi T Maeda H Ikeda M Imai K 《Australasian physical & engineering sciences in medicine / supported by the Australasian College of Physical Scientists in Medicine and the Australasian Association of Physical Sciences in Medicine》2011,34(4):481-488
Aims of present study were to examine usefulness of information theory in visual assessment of image quality. We applied first order approximation of the Shannon's information theory to compute information losses (IL). Images of a contrast-detail mammography (CDMAM) phantom were acquired with computed radiographies for various radiation doses. Information content was defined as the entropy Σp( i )log(1/p ( i )), in which detection probabilities p ( i ) were calculated from distribution of detection rate of the CDMAM. IL was defined as the difference between information content and information obtained. IL decreased with increases in the disk diameters (P < 0.0001, ANOVA) and in the radiation doses (P < 0.002, F-test). Sums of IL, which we call total information losses (TIL), were closely correlated with the image quality figures (r = 0.985). TIL was dependent on the distribution of image reading ability of each examinee, even when average reading ratio was the same in the group. TIL was shown to be sensitive to the observers' distribution of image readings and was expected to improve the evaluation of image quality. 相似文献
133.
Tsuyoshi Miyazaki Shigeru Kobayashi Kenichi Takeno Takafumi Yayama Adam Meir Hisatoshi Baba 《Knee surgery, sports traumatology, arthroscopy》2011,19(7):1198-1205
Purpose
A lot of studies on the effect of intra-articular injections are clinical, but many questions on the effect of lidocaine to articular chondrocytes remain unanswered. This study was performed to determine the effects of varying concentrations and exposure times of lidocaine on the viability and proteoglycan metabolism of chondrocytes in vitro. 相似文献134.
Katsunobu Oyama Sachio Fushida Tomoya Tsukada Jun Kinoshita Toshifumi Watanabe Masatoshi Shoji Shinichi Nakanuma Koichi Okamoto Seisho Sakai Isamu Makino Keishi Nakamura Hironori Hayashi Masafumi Inokuchi Hisatoshi Nakagawara Tomoharu Miyashita Hidehiro Tajima Hiroyuki Takamura Itasu Ninomiya Hirohisa Kitagawa Takashi Fujimura Ryousuke Tajiri Akishi Ooi Tetsuo Ohta 《Journal of gastroenterology》2015,50(1):121-122
135.
Maruyama Mitsunari Yoshizako Takeshi Araki Hisatoshi Yoshida Rika Ando Shinji Nakamura Megumi Kitagaki Hajime 《Cardiovascular and interventional radiology》2018,41(12):1877-1884
CardioVascular and Interventional Radiology - To evaluate the utility of future liver remnant plasma clearance rate of indocyanine green (ICGK-F) for predicting post-hepatectomy liver failure... 相似文献
136.
137.
Narimatsu S Yonemoto R Masuda K Katsu T Asanuma M Kamata T Katagi M Tsuchihashi H Kumamoto T Ishikawa T Naito S Yamano S Hanioka N 《Biochemical pharmacology》2008,75(3):752-760
The oxidative metabolism of 5-methoxy-N,N-diisopropyltryptamine (5-MeO-DIPT), a tryptamine-type designer drug, was studied using rat liver microsomal fractions and recombinant cytochrome P450 (CYP) enzymes. 5-MeO-DIPT was biotransformed mainly into a side-chain N-deisopropylated metabolite and partially into an aromatic ring O-demethylated metabolite in liver microsomal fractions from untreated rats of both sexes. This metabolic profile is different from our previous findings in human liver microsomal fractions, in which the aromatic ring O-demethylation was the major pathway whereas the side-chain N-deisopropylation was minor [Narimatsu S, Yonemoto R, Saito K, Takaya K, Kumamoto T, Ishikawa T, et al. Oxidative metabolism of 5-methoxy-N,N-diisopropyltryptamine (Foxy) by human liver microsomes and recombinant cytochrome P450 enzymes. Biochem Pharmacol 2006;71:1377-85]. Kinetic and inhibition studies indicated that the side-chain N-dealkylation is mediated by CYP2C11 and CYP3A2, whereas the aromatic ring O-demethylation is mediated by CYP2D2 and CYP2C6 in untreated male rats. Pretreatment of male rats with beta-naphthoflavone (BNF) produced an aromatic ring 6-hydroxylated metabolite. Recombinant rat and human CYP1A1 efficiently catalyzed 5-MeO-DIPT 6-hydroxylation under the conditions used. These results provide valuable information on the metabolic fate of 5-MeO-DIPT in rats that can be used in the toxicological study of this designer drug. 相似文献
138.
Perinatal exposure to estrogens such as diethylstilbestrol (DES), and to estrogenic chemicals, induces persistent anovulation caused by alteration of hypothalamic-pituitary-gonadal (HPG) axis, polyovular follicles, uterine abnormalities and persistent vaginal changes in mice. Most activities of estrogenic chemicals are mediated through estrogen receptor alpha (ERalpha) and/or ERbeta. However, little was known about the relative contribution of the individual ER subtypes in induction of abnormalities. We tested the effects of neonatal exposure to ER selective ligands and DES on female mice. Transactivation assays using mouse ERalpha and ERbeta showed that 10(-10)M DES activated both ER subtypes and that the ERalpha agonist (propyl pyrazole triol, PPT) and the ERbeta agonist (diarylpropionitrile, DPN) selectively activated their respective ERs at 10(-9)M. Neonatal female mice were injected subcutaneously with DES, PPT or DPN and the animals were examined at 13 and 15 weeks of age, respectively. Persistent estrous smears and anovulation were induced in all mice by 0.025-2.5 microg DES and 2.5-25 microg PPT, but not by DPN, suggesting that the observed anovulation was primarily mediated through ERalpha. Disorganization of uterine musculature and ovary-independent vaginal epithelial cell proliferation accompanied by persistent expression of EGF-related genes and interleukin-1-related genes were also mediated through ERalpha. In contrast, polyovular follicles were induced by neonatal treatment with both ERalpha and ERbeta ligands, suggesting that ovarian abnormalities are mediated through both ER subtypes. 相似文献
139.
140.
Nobuo Murata Yasuo Idezuki Toshiro Konishi Hiromu Watanabe Yoshio Ushirokoji Kazuhiko Shinohara Miki Shibusawa Shunsuke Haga Mamoru Hiraishi Yasutsugu Bandai Takuya Yamamura Shunichi Yumoto Atsuaki Gunji Katsu Nishigaki 《Gastric cancer》2000,3(1):24-27
Background. The deleterious effect of blood transfusions on survival has been reported in patients with cancers of various organs. However,
it remains unclear whether there is any adverse effect of blood transfusion when the patients are administered anticancer
drugs after surgery for gastric cancers.
Methods. Data from patients with gastric resection for advanced gastric cancer were retrospectively analyzed to determine the influence
of perioperative blood transfusion on the survival rate. All patients were administered anticancer drugs (mitomycin C [MMC]
and tegafur-uracil [UFT]). Sixty-nine (33%) of 208 patients received blood transfusion perioperatively, while 139 patients
(67%) did not receive transfusion. Multivariate analysis of clinicopathologic prognostic factors, including blood transfusion,
was performed. Lymphocyte subsets were measured to investigate the immunosuppressive effect of blood transfusion.
Results. The 5-year survival rate was 48.8% in the 69 transfused patients and 66.9% in the 139 non-transfused patients (P < 0.01). Cox's multiple regression analysis showed that, when patients received anticancer drugs, perioperative blood transfusion
was not a significant factor affecting survival after the gastric cancer surgery. However, the CD4/CD8 ratio at 3 months after
the surgery was significantly lower in the transfused group than in the non-transfused group.
Conclusion. Blood transfusion did not affect the survival of operated patients who received postoperative adjuvant chemotherapy. However,
the finding that the ratio of CD4/CD8 after surgery was significantly higher in the non-transfused group than in the transfused
group supports the notion that transfusion causes broad-spectrum immunosuppression.
Received: December 13, 1999 / Accepted: March 15, 2000 相似文献