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排序方式: 共有419条查询结果,搜索用时 15 毫秒
41.
Y Tanaka Y Takakura T Takaoka K Akiyama T Fujii S Tamai 《Canadian Metallurgical Quarterly》1997,(336):186-194
To investigate changes in the radiographic appearance during weightbearing in hallux valgus and to examine the importance of a weightbearing view, a comparative study was performed of accurate dorsoplantar radiographs of 108 symptomatic hallux valgus feet in 73 female patients and 100 normal feet in 69 females, which were taken weightbearing and nonweightbearing. The hallux valgus angle in the hallux valgus group increased on weightbearing, whereas that in the normal group decreased. The intermetatarsal angle between the first and second metatarsals increased on weightbearing in both groups. The degree of the changes of the angles was closely related with the degree of the hallux valgus deformity. The intermetatarsal angle between the fourth and fifth metatarsals decreased on weightbearing in the both groups. A weightbearing view is necessary to evaluate the structural configuration of hallux valgus, because muscle imbalance around the first metatarsophalangeal joint in hallux valgus causes an increase of a hallux valgus angle on weightbearing. 相似文献
42.
Yasuo Watanabe Masahiro Yamaguchi Yumi Sanemitsu Youichi Tamai 《Yeast (Chichester, England)》1991,7(6):599-606
Plasma membrane was isolated from the salt-tolerant yeast Zygosaccharomyces rouxii and from Saccharomyces cerevisiae. The ATPase in the plasma membrane of Z. rouxii cells was a typical proton-ATPase as judged by testing with various ATPase inhibitors. There were slight differences in the pH optima of activities and in the sensitivity to sodium chloride (NaCl) and potassium chloride (KCl) of the ATPase from Z. rouxii and S. cerevisiae. The specific ATPase activity from Z. rouxii was higher in cells grown in a medium containing 2 M-NaCl than in those not containing NaCl. No in vivo activation by incubation with glucose was observed in Z. rouxii cells and the specific ATPase activity was independent of the growth phase, unlike S. cerevisiae cells. 相似文献
43.
Ikuo Yanase Sachiko Tamai Hidehiko Kobayashi 《Journal of the American Ceramic Society》2003,86(8):1360-1364
Cubic cesium leucite-based compounds, namely cesium leucites, cesium sodium leucites, and cesium lithium leucites, were synthesized using a multistep solid-state reaction method. The thermal expansion properties, in the temperature range of 298-1273 K, for the synthesized cubic cesium leucite-based compounds were examined using high-temperature powder X-ray diffractometry data. The thermal expansions of the cubic cesium leucite-based compounds were found to vary with the chemical composition. For instance, the thermal expansions of Cs0.7 Na0.2 Al0.9 Si2.1 O6 and Cs0.7 Li0.2 Al0.9 Si2.1 O6 were 0.14% at 1273 K and 0.081% at 1073 K, values lower than those of Cs0.9 Al0.9 Si2.1 O6 , which were 0.16% at 1073 K and 0.2% at 1273 K. The results showed that the thermal expansions of the cubic cesium leucite-based compounds changed with ionic substitution at the Cs+ sites because of ionic size differences between Cs+ and the Na+ or Li+ substitutional ions. 相似文献
44.
This article deals with preparations of fine particles of metallocene copolymers by emulsifierfree emulsion polymerization of vinylferrocene (VFc), ferrocenylmethyl methacrylate (FMMA), 1-ferrocenylethyl methacrylate (1-FEMA), 2-ferrocenylethyl methacrylate (2-FEMA), and 1-ruthenocenylethyl methacrylate (1-REMA) with acrylonitrile (AN), styrene (St), and methyl methacrylate (MMA) in water/ethanol medium. As a result, spherical copolymer particles containing metallocene derivatives have been successfully synthesized in the particle size of ca. 120 to 600 nm. The contents of ferrocenyl or ruthenocenyl groups in copolymer particles increased with increasing concentration of charged metallocene derivatives, while the amounts of metallocene derivatives incorporated into particles are much lower than the charged ratio. © 1994 John Wiley & Sons, Inc. 相似文献
45.
K Hanada D Sawamura K Tamai T Baba I Hashimoto T Muramatsu N Miura A Naganuma 《Canadian Metallurgical Quarterly》1998,111(4):582-585
The alien hand sign refers to a group of signs which include a feeling that the hand is foreign together with autonomous activity, as if the hand is driven by an external agent. These features are commonly associated with frontal and callosal lesions. We report the alien hand sign in a man with left medial cortical infarct, presenting with autonomous grasping and groping with his right upper limb, denial of ownership of his limb, and dissociative phenomena including self restriction and intermanual conflict. 相似文献
46.
Gene transfer into a panel of non-small cell lung cancer (NSCLC) cells by adenoviral (Ad) and retroviral (RV) vectors was studied. Indexed to multiplicity of infection (MOI), Ad vectors transduce squamous, adenosquamous, and malignant mesothelioma cells with greater efficiency than large cells or adenocarcinoma cells. Transduction-sensitive cells bind the Ad vector with specificity for the Ad fiber knob, and internalize vector efficiently. Transduction-refractory cells bind and internalize vector by less efficient pathways. Like Ad vectors, there is heterogeneity in RV transduction efficiencies of different NSCLC subtypes. With respect to the most common cell type metastatic to the pleural space (adenocarcinoma), amphotropic retroviral vectors transduce cells of this subtype more efficiently (at a lower MOI) than Ad. RV transduction is not solely dependent on cellular replication, and both permissive and refractory cell lines express the mRNA for the amphotropic RV receptor. These observations suggest that neither Ad nor RV vectors will suffice a priori as the optimal gene transfer vehicle, and successful gene therapy of lung cancer may require tumor-specific or patient-specific vectors. 相似文献
47.
2-Amino-3-methylimidazo[4,5-f]quinoline (IQ) and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) are two members of a family of carcinogenic heterocyclic amines (HAs) found in cooked meats that form DNA adducts after activation to N-acetoxy derivatives. The ability of IQ- and PhIP-DNA adducts to inhibit gene expression was investigated using a human growth hormone (hGH) reporter gene in a pUC12-based mammalian expression vector under the control of either the herpes simplex virus-1 thymidine kinase promoter or the human immunodeficiency virus-1 long terminal repeat. The plasmids were treated in vitro with 0, 5, 10, or 40 microM N-hydroxy-IQ or N-hydroxy-PhIP in the presence of a 10-fold molar excess of acetic anhydride to generate the N-acetoxy derivatives in situ. The adduct levels in the plasmids were quantitated by the 32P-postlabeling method. The adducted (and control) plasmids were each transfected into repair-deficient or -proficient Chinese hamster ovary cells, and expression of hGH was measured by immunoassay of growth hormone secreted into the cell medium. The results showed that IQ- and PhIP-DNA adducts inhibited gene expression in both plasmids and that the degree of inhibition of hGH production was proportional to the levels of IQ- and PhIP-DNA adducts. The degree of inhibition, however, was independent of the promoter, despite the differences in the strengths of the two promoters to drive hGH production. Repair capacity influenced the extent of inhibition of gene expression by HA adducts since, in general, fewer adducts were needed to inhibit reporter gene expression in repair-deficient cells than in repair-proficient cells. In both cell lines, DNA adducts of PhIP appeared to be more potent in inhibiting hGH expression than adducts of IQ. Whether alteration of gene expression by HA adducts plays a role in the carcinogenicity of these compounds deserves further study. 相似文献
48.
I Tamai H Takanaga H Maeda T Ogihara M Yoneda A Tsuji 《Canadian Metallurgical Quarterly》1995,12(11):1727-1732
PURPOSE: The purpose of the present study is to clarify the intestinal brush-border transport mechanism of a weak organic acid, pravastatin, an HMG-CoA reductase inhibitor. METHODS: The transport of pravastatin was studied by using intestinal brush-border membrane vesicles prepared from rabbit jejunum, and uptake by the membrane vesicles was measured using rapid filtration technique. RESULTS: The initial uptake of [14C]pravastatin was markedly increased with decreases in extravesicular pH and showed a clear overshoot phenomenon in the presence of a proton gradient (pHin/out = 7.5/5.5). A protonophore, carbonylcyanide p-trifluoromethoxyphenylhydrazone, significantly reduced the uptake of [14C]pravastatin. In addition, an ionophore for sodium, potassium and proton, nigericin, stimulated the uptake of [14C]pravastatin in the presence of a potassium gradient ([K+]in/[K+]out = 0/145 mM). On the other hand, neither the imposition of an inwardly directed sodium gradient nor an outwardly directed bicarbonate gradient stimulated the uptake of [14C]pravastatin. In the presence of a proton gradient (pHin/out = 7.5/5.5), the initial uptake of pravastatin was saturable with the apparent Kt of 15.2 +/- 3.2 mM and Jmax of 10.6 +/- 1.21 nmol/mg protein/10 sec. The uptake of pravastatin was significantly inhibited by monocarboxylic acid compounds such as acetic acid and nicotinic acid in a competitive manner but not by di- or tricarboxylic acids, or acidic amino acid. CONCLUSION: It was concluded that a pH-dependent transport of pravastatin across the brush-border membrane occurs by a proton-gradient dependent carrier-mediated mechanism rather than by simple diffusion of its unionized form. 相似文献
49.
50.
I Hino T Tamai K Satoh H Takashima M Ohkawa M Tanabe 《Canadian Metallurgical Quarterly》1997,18(11):1040-1048
To predict residual liver function before hepatic resection, we devised a predictive index by combining clearance values with functional liver volume measured by liver dynamic single photon emission tomography (SPET). Forty-seven patients with liver disease underwent liver dynamic SPET with 99Tcm-Sn colloid before hepatic resection. There were no operation-related deaths. Three patients died from hepatic failure more than 1 month following the operation. Their predictive indices were 0.24, 0.33 and 0.34. When the predictive index was above 0.35, no patient had symptoms of hepatic failure or died. Our data suggest that when the predictive index is above 0.35, there is a low probability of hepatic failure after hepatectomy. 相似文献