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61.
62.
Kei Matsuzaki Ken Ishihara Yoshinao Shinohara Taiichi Kanai 《Macromolecular chemistry and physics.》1986,187(9):2199-2208
Oligostyryllithium was synthesized by the reaction of sec-butyllithium with styrene in diethyl ether at ?40°C. Dimer model anions (counter cations: Li and K) of the growing chain ends were synthesized by metallation of 1-methoxy-1,3-diphenylpropane. The structures of the lithium compounds were corroborated by 13C NMR spectroscopy and compared with those of the potassium compounds. As for polystyryllithium and its model compounds, the charge density on the α-carbon increased and that on the phenyl ring of the growing end decreased with increasing molecular weight, while, in polystyrylpotassium and its model compounds, the charge density on the α-carbon increased and the one on the phenyl ring did not change with increasing molecular weight. The temperature change of the 1H NMR spectrum of oligostyryllithium in diethyl ether indicated rotation around the C-1? Cα bond at lower temperatures than in tetrahydrofuran, but the activation energy was the same in both solvents. T1 values of the phenyl carbons in model compound 2b were one to two orders of magnitude shorter than those of the protonated compound. 相似文献
63.
Yoshiharu Yamamoto Mitsumasa Miyashita Richard L. Hughson Shin-ichi Tamura Minoru Shinohara Yoshiteru Mutoh 《European journal of applied physiology》1991,63(1):55-59
Summary The purpose of this study was to examine whether the ventilatory threshold (Th
v) would give the maximal lactate steady state ([1a]ss, max), which was defined as the highest work rate (W) attained by a subject without a progressive increase in blood lactate concentration [1a]b at constant intensity exercise. Firstly, 8 healthy men repeated ramp-work tests (20 W·min–1) on an electrically braked cycle ergometer on different days. During the tests, alveolar gas exchange was measured breath-by-breath, and theW atTh
v (W
Th
v) was determined. The results of two-way ANOVA showed that the coefficient of variation of a singleW
Th
v determination was 2.6%. Secondly, 13 men performed 30-min exercise atW
Th
v (Th
v trial) and at 4.9% aboveW
Th
v (Th
v + trial), which corresponded to the 95% confidence interval of the single determination. The [1a]b was measured at 15 and 30 min from the onset of exercise. The [1a]b at 15 min (3.15 mmol·1–1, SEM 0.14) and at 30 min (2.95 mmol·1–1, SEM 0.18) were not significantly different inTh
v trial. However, the [1a]b ofTh
v+ trial significantly increased (P<0.05) from 15 min (3.62 mmol·1–1, SEM 0.36) to 30 min (3.91 mmol·1–1, SEM 0.40). These results indicate thatTh
v gives the [1a]ss,max, at which one can perform sustained exercise without continuous [1a]b accumulation. 相似文献
64.
Yasushi Nakayama Junji Saito Hideki Bando Terunori Fujita 《Macromolecular chemistry and physics.》2005,206(18):1847-1852
Summary: Fluorinated bis(phenoxy‐imine)Ti complexes 1 – 3 combined with MgCl2/i‐BunAl(OR)3−n (MgCl2‐supported catalysts) were able to polymerize propylene in a living fashion at room temperature to provide slightly to highly syndiotactic poly(propylenes) (PPs) with extremely narrow distributions of molecular weight. These represent the first examples of MAO‐ and borate‐free group 4 metal‐based living catalysts. The supported complexes 2 and 3 formed PPs with higher syndiotacticity and Tm's than the corresponding homogeneous MAO‐activation systems (e.g., 3 : rr 97%, Tm 155 °C; MAO activation: rr 93%, Tm 152 °C). The measured Tm of 155 °C represents the highest known Tm for syndiotactic PPs synthesized at room temperature.
65.
In situ hybridisation with digoxigenin-labelled DNA probes for detection of viral genomes. 总被引:2,自引:2,他引:2 下载免费PDF全文
The applicability of a recently developed non-radioactive DNA labelling and detection method, which uses the digoxigenin (DIG) enzyme linked immunosorbent assay (ELISA) system, for the detection of viral infections in pathology specimens by in situ hybridisation, was examined. Its efficacy was compared with that of biotin and radioisotope labelling methods. Three cases of progressive multifocal leucoencephalopathy, two of verruca vulgaris, and seven cases of laryngeal papilloma were studied. The sensitivity of the DIG labelled probe was almost the same as that of a 35S-labelled probe in the dot-blot hybridisation test. Using in situ hybridisation with 35S-labelled and DIG labelled probes, the levels of the hybridised signals detected were similar. The biotin labelled probe was less sensitive, particularly in the cases of laryngeal papilloma. The DIG labelling and detection method was highly sensitive and applicable to the detection of viral infection by ISH, and is preferable to a radiolabelled probe, especially when in situ hybridisation is done in the pathology laboratory. 相似文献
66.
Shinohara Y Iwasaki H Ota N Nakajima T Kodaira M Kajita M Shiba T Emi M 《Journal of human genetics》2001,46(1):50-51
The nuclear factor kappa-B 2 (NFKB2) gene is a member of the NFKB/Rel gene family, which is known to be a pivotal regulator of the acute phase of the inflammatory
response and of immune responses. We identified three novel single nucleotide polymorphisms (SNPs) and determined their allelic
frequencies, as determined by the sequencing of 48 alleles of the entire gene in a Japanese population sample. Two of the
three polymorphisms were identified at nucleotide (nt) position 1837 (T/C) and nt position, 1867 (GG/G) in the upstream region
of the gene. The other polymorphism was identified at nt position 2584 (G/T) within intron 1. These polymorphisms will be
useful in genetic studies of the processes involved in inflammatory responses and in bone differentiation.
Received: October 17, 2000 / Accepted: October 23, 2000 相似文献
67.
Immature dendritic cells (CD11c+ CD3- B220- cells) present in mouse peripheral blood 总被引:1,自引:0,他引:1
Adachi Y Toki J Ikebukuro K Tomita M Kaneda H Tanabe A Jun L Minamino K Suzuki Y Taketani S Ikehara S 《Immunobiology》2002,206(4):354-367
It is well known that dendritic cells (DCs) are developed from the peripheral blood of mice when peripheral blood mononuclear cells (PBMCs) are cultured with GM-CSF. We have previously found that immature DCs are present in the blood even in humans. In the present study, we show that CD11c+ CD3- B220- cells in the mouse peripheral blood are immature DCs. The percentage of CD11c+ CD3- B220- cells in the (PBMCs) of normal mice ranges from 0.5 to 2.5%. The CD11c+ CD3- B220- cells in the PBMCs show dendrites, similar in shape to the CD11c+ CD3- B220- cells in the spleen, which are thought to be DCs definitely. However, they have practically no capacity to stimulate the proliferation of allogeneic T cells, and show a lower expression of MHC class II, B7-1 and B7-2 than CD11c+ CD3- B220- cells in the spleen. When the CD11c+ CD3- B220- cells in the PBMCs are cultured with GM-CSF, they show not only the potent ability to stimulate the proliferation of allogeneic T cells but also a higher expression of MHC class II, B7-1 and B7-2. Moreover, they migrate into the spleen when they are injected intravenously. These results suggest that CD11c+ CD3- B220- cells in the PBMCs are immature DCs, and that they migrate into the spleen, where they mature. 相似文献
68.
N-methyl-D-aspartate receptor antagonist reduces nitrotyrosine formation in caudate-putamen in rat focal cerebral ischemia-reperfusion 总被引:2,自引:0,他引:2
Hirabayashi H Takizawa S Fukuyama N Nakazawa H Shinohara Y 《Neuroscience letters》2001,299(1-2):159-161
The aim of this study is to determine experimentally whether N-methyl-D-aspartate (NMDA) receptor is involved in nitrotyrosine formation in rat brain subjected to focal ischemia-reperfusion, by using the NMDA receptor antagonist MK-801. Halothane-anesthetized and artificially ventilated rats were given MK-801 (5 mg/kg, i.p.) or vehicle prior to 2 h of focal cerebral ischemia followed by 0.5 h of reperfusion. The brain was then removed and divided into four sections, cortical ischemic core, peri-ischemic cortex, lateral caudate-putamen and non-ischemic cortex. Tissue nitrotyrosine was measured by means of hydrolysis/HPLC. MK-801 significantly attenuated nitrotyrosine formation in the lateral caudate-putamen. We conclude that nitrotyrosine formation required activation of NMDA receptors, at least in part. 相似文献
69.
70.
Tadashi Yasuda Hirokazu Imai Yasushi Nakamoto Akira B. Miura Shiegki Inomata 《Virchows Archiv : an international journal of pathology》1992,421(4):297-303
Summary The pathogenesis of the nodular lesion in diabetic glomerulosclerosis is described in association with fibrils. Thirteen diabetic patients with glomerular nodular lesions and 9 diabetics without the nodules were examined by electron microscopy using periodic acid-thio-carbohydrazide-silver proteinate staining. In cases of nodular glomerulosclerosis, abundant fibrillar structures mixed with electron-dense material were detected within the nodule and the mesangial matrix. They were also occasionally observed along the subendothelial space of the glomerular capillary walls. On the cross-section, these fibrils, including the lucent periphery, were 34 nm wide. Immunohistologically, collagen V and collagen VI were detected in nodular lesions. In contrast, in cases of the diffuse type of glomerulosclerosis, the widened mesangium was composed of dense material, which resembled the original mesangial matrix. The above fibrils were not detected in the mesangium. These findings suggest that the accumulation of the peculiar fibrils in the glomerular mesangium is a major pathogenic factor in the formation of Kimmelstiel-Wilson nodules. 相似文献