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排序方式: 共有821条查询结果,搜索用时 15 毫秒
1.
2.
Masamitsu Shirai Tatsuki Nagatsuka Makoto Tanaka 《Macromolecular chemistry and physics.》1978,179(1):173-179
The effect of polyanions on the formation of mixed dimers of methylene blue ( 1 ) and trypaflavine ( 2 ), methylene blue ( 1 ) and phenosafranine ( 3 ), and methylene blue ( 1 ) and pyronine G ( 4 ) was investigated spectrophotometrically. The following polyanions were used: poly(potassium styrenesulfonate) (PSS), poly(potassium vinyl sulfate) (PVS), and poly(sodium acrylate) (PAA). On addition of polyanions, the formation of mixed dimers was enhanced largely. Thermodynamic parameters inferred that the enhancement of the formation of mixed dimers in the presence of polyanions resulted from an entropic factor. 相似文献
3.
Masamitsu Shirai Tatsuki Nagatsuka Makoto Tanaka 《Macromolecular chemistry and physics.》1977,178(1):37-46
The structural effect of polyanions on the binding type of methylene blue ( 1 ) was investigated spectrophotometrically. 1 was bound to poly(potassium styrenesulfonate) (PSS) and poly(sodium 4-vinylphenylsulfate) (SVS) in the dimeric or slightly aggregated form and to poly(sodium vinylsulfonate) (SVF) and poly(potassium vinyl sulfate) (PVS) in the highly aggregated (polymeric) form. It was found that the flexibility of polyanions plays an important rǒle in the aggregation of bound 1 and that the difference between ? SO and ? OSO as binding site is not a significant factor. 相似文献
4.
Cellular niches controlling B lymphocyte behavior within bone marrow during development 总被引:19,自引:0,他引:19
In bone marrow, hematopoiesis is thought to depend on special microenvironments known as niches that maintain blood cells. However, the identity of niches and interaction of blood cells with niches remain poorly understood. Here we identify stage-specific cellular niches for B lymphopoiesis. The earliest precursors, pre-pro-B cells and end-stage B cells, plasma cells require CXC chemokine ligand (CXCL)12. CXCL12-expressing cells are a small population of stromal cells, scattered throughout bone marrow and located some distance from the cells expressing interleukin (IL)-7. Multipotent hematopoietic progenitors are attached to the processes of CXCL12-expressing cells and pre-pro-B cells adjoin their cell bodies. Maturer pro-B cells that require IL-7 have moved away and adjoin the IL-7-expressing cells. Plasma cells again seed CXCL12-expressing cells. We demonstrate the B lymphocyte characteristic location and movement between specific niches within bone marrow during development and suggest that CXCL12 maintains the cells in the niche. 相似文献
5.
Koichi Hatada Tatsuki Kitayama Keith Saunders Robert W. Lenz 《Macromolecular chemistry and physics.》1981,182(5):1449-1458
The 13C NMR spectra measured at 25 MHz of the methyl and propyl esters of isotactic and syndiotactic poly(α-bromoacrylate) were sufficiently resolved to be analysed for pentad tacticity sequences. The pentad tacticity of the syndiotactic polymers prepared with free radical initiators at ?40°C agreed with those calculated for Bernoullian sequence distributions based on Pr values of 0,83–0,87. The tacticities of the isotactic polymers prepared with heterogeneous catalysts were determined on the basis of these assignments. Good internal consistency was obtained between the calculated and observed pentad proportions from the quaternary and carbonyl carbon peaks in the spectra of these polymers. The order of chemical shifts for the meso and racemic dyads and tetrads in these polymers were opposite to those found in the equivalent methacrylate polymers, but as with the latter, the 13C-T1 values were longer in the isotactic than in the syndiotactic polymers. 相似文献
6.
M Sawada K Otsuki K Mitsukawa K Yakuwa M Nagatsuka T Okai 《International journal of gynaecology and obstetrics》2006,92(2):117-121
OBJECTIVE: To evaluate concentrations of interleukin (IL)-6, IL-8, lactoferrin (LF), and alpha defencine (alpha-DF) in the cervical mucus of pregnant women and analyze their relation to cervicitis and bacterial vaginosis (BV). METHODS: Cervical mucus samples were obtained from August 2003 through May 2004 from 157 women who were between the 6th and 36th week of an uncomplicated singleton pregnancy. All women were delivered at term, 69 without BV or cervicitis, 9 with BV, and 79 with cervicitis. RESULTS: Interleukin 8, LF, and mu-DF concentrations were higher in women with cervicitis (0.81 +/- 0.36 pg/mL, 14.8+/-12.3 microg/mL, and 0.60 +/- 0.49 microg/mL) than in women without BV or cervicitis (0.35 +/- 0.34 pg/mL, 8.0 +/- 11.0 microg/mL, and 0.15 +/- 0.12 microg/mL). Interleukin 6 concentration was higher in women with BV (0.26 +/- 0.32 pg/mL) than in women without BV or cervicitis (0.09 +/- 0.15 pg/mL) or in women with cervicitis (0.12 +/- 0.18 pg/mL). CONCLUSIONS: Higher levels of inflammatory cytokines in the cervical mucus of pregnant women may lead to early detection of lower genital tract infection. 相似文献
7.
Yakuwa K Otsuki K Nakayama K Hasegawa A Sawada M Mitsukawa K Chiba H Nagatsuka M Okai T 《Archives of gynecology and obstetrics》2007,275(5):331-334
Objective To investigate the effect of recombinant human lactoferrin (rhLF) on cervical ripening using a rabbit model in which preterm
labor was induced by bacterial endotoxin lipopolysaccharide (LPS).
Study design Timed pregnant rabbits (New Zealand White, 3–4 kg, day 14) were randomly assigned to the following treatment groups: Group
A, LPS + rhLF (n = 4); Group B, LPS (n = 4); and Group C, control (n = 4). Recombinant human lactoferrin (10 μg) was administrated to pregnant rabbits in Group A and not in Group B. Lipopolysaccharide
(100 μg) was given to the rabbits in both groups for 3 days (days14–16). Drugs were administered as a vaginal suppository.
On day 18, the rabbits were anesthetized with intramuscular ketamine hydrochloride (20 mg/kg) and diazepam (4 mg/kg). Both
cervices of the rabbit uterus, which is bicorpus-bicolli, were taken out. One cervix was placed in 10% formalin solution for
a histological study with standard hematoxylin-eosin staining. The other was used for an extension test to assess the grade
of ripening. Extension was measured after a 5-mm length of cervical tissue was loaded with 5.8 g.
Results The histological study showed remarkably loose and edematous connective tissue in Group B cervices. Cervical tissues in Group
A was not different from those in Group C. Extension lengths were 2.2 ± 0.2 mm in Group A, 7.0 ± 2.7 mm in Group B, and 1.7 ± 0.3 mm
in Group C.
Conclusion These results suggest that rhLF inhibits cervical maturation induced by LPS in a rabbit model and may have a potential to
prevent preterm delivery caused by cervical infection and ripening. 相似文献
8.
Shintaro Sukegawa Rieko Shimizu Yuka Sukegawa Kazuaki Hasegawa Sawako Ono Ai Fujimura Izumi Yamamoto Keisuke Nakano Kiyofumi Takabatake Hotaka Kawai Hitoshi Nagatsuka Yoshihiko Furuki 《Materials》2022,15(9)
This retrospective study clarified the success rate of endoscopic endodontic surgeries and identified predictors accounting for successful surgeries. In this retrospective study, 242 patients (90 males, 152 females) who underwent endoscopic endodontic surgery at a single general hospital and were diagnosed through follow-up one year later were included. Risk factors were categorized into attributes, general health, anatomy, and surgery. Then, the correlation coefficient was calculated for the success or failure of endodontic surgery for each variable, the odds ratio was calculated for the upper variable, and factors related to the surgical prognosis factor were identified. The success rate of endodontic surgery was 95.3%, showing that it was a highly predictable treatment. The top three correlation coefficients were post, age, and perilesional sclerotic signs. Among them, the presence of posts was the highest, compared with the odds ratio, which was 9.592. This retrospective study revealed the success rate and risk factors accounting for endoscopic endodontic surgeries. Among the selected clinical variables, the presence of posts was the most decisive risk factor determining the success of endodontic surgeries. 相似文献
9.
Miyaaki H Ichikawa T Yatsuhashi H Taura N Miuma S Usui T Mori S Kamihira S Tanaka Y Mizokami M Nakao K 《Hepatology research》2011,41(12):1216-1222
Aim: The aim of this study was to investigate the relationship among the expression of suppressor of cytokine signaling 3 (SOCS 3) in the liver, the SNPs in the IL28B locus, and the outcome of interferon therapy. Methods: Prior to interferon treatment, we immunostained 67 liver specimens from chronic hepatitis C (CHC) patients who were receiving peginterferon alpha‐2b/ribavirin therapy for suppressor of cytokine signaling 3 (SOCS3), and compared the expression of SOCS3, IL28 polymorphisms and other clinical factors between the patients and compared their eventual outcomes. Results: Significant differences between the low SOCS3 group and high SOCS3 group were found in age, as well as in the platelet, transaminase, gamma‐glutamyl transpeptidase levels. The incidence of high SOCS3 was not significantly different between subjects with the TT genotype and the TG genotype (TT : TG = 71%:29%, P = 0.250). In a multivariate analysis, age (≥65 years old) (odds ratio 0.221 [0.120–0.966], P = 0.045), IL28B gene (genotype TT) (odds ratio 5.422 [1.254–23.617], P = 0.024) and SOCS3 (high) (odds ratio 0.308 [0.104–0.948], P = 0.040) were significant predictors of the interferon response. In patients with the TT genotype, those with low SOCS3 immunostaining showed a high sustained virological response (69%), while the sustained virological rate was low (27%) in the patients with high SOCS3 immunostaining. Conclusions: Using a combination of the SOCS3 immunostained area in the liver and the expression of IL28B single nucleotide polymorphisms might be a useful predictor of hepatitis C virus clearance by interferon therapy. 相似文献
10.
Tatsuki Nanami Hideaki Shimada Satoshi Yajima Yoko Oshima Kazuyuki Matsushita Fumio Nomura Matsuo Nagata Masatoshi Tagawa Seiko Otsuka Akiko Kuwajima Hironori Kaneko 《Esophagus》2016,13(2):167-172