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1.
In order to evaluate the gastric emptying and postprandial mixing of bile with food, the scintigraphies of hepatobiliary and gastrointestinal tracts by using three different kinds of radioisotopes were performed simultaneously (99mTc-E.HIDA for hepatobiliary scintigraphy, 111In-DTPA containing orange juice and 131I-albumin containing scrambled egg for gastrointestinal scintigraphy). This method was available for observation of gastric emptying of liquid and solid foods and also examination of the mixing effect of bile and food quantitatively.  相似文献   
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We have reported that photodynamic therapy (PDT) using the photosensitizer phthalocyanine (Pc) 4 and red light damages the antiapoptotic protein Bcl-2. Recently, using transient transfection of Bcl-2 deletion mutants, we identified the membrane anchorage domains of Bcl-2 as necessary to form the photosensitive target. However, it is not clear how Bcl-2 photodamage sensitizes cells to Pc 4-PDT-induced apoptosis, whether overall cell killing is also sensitized or how up-regulation of Bcl-2 in tumors might make them more or less responsive to Pc 4-PDT. In this study we report on MCF-7c3 cells (human breast cancer cells expressing stably transfected procaspase-3) overexpressing wild-type Bcl-2 or certain deletion mutants in either a transient or a stable mode. By flow cytometric analysis of transiently transfected cells, we found that wild-type Bcl-2, Bcl-2delta33-54 and Bcl-2delta37-63 (each of which can be photodamaged) protected cells from apoptosis caused by Pc 4-PDT. In contrast, Bcl-2delta210-239, which lacks the C-terminal transmembrane domain and cannot be photodamaged, afforded no protection. We then evaluated the PDT sensitivity of transfected cell lines stably overexpressing high levels of wild-type Bcl-2 or one of the Bcl-2 mutants. Overexpression of wild-type Bcl-2, Bcl-2delta33-54 or Bcl-2delta37-63 resulted in relative resistance of cells to Pc 4-PDT, as assessed by morphological apoptosis or loss of clonogenicity. Furthermore, overexpression of Bcl-2 also inhibited the activation-associated conformational change of the proapoptotic protein Bax, and higher doses of Pc 4 and light were required to activate Bax in cells expressing high levels of Bcl-2. Many advanced cancer cells have elevated amounts of Bcl-2. Our results show that increasing the dose of Pc 4-PDT can overcome the resistance afforded by either Bcl-2 or the two mutants. PDT regimens that photodamage Bcl-2 lead to activation of Bax, induction of apoptosis and elimination of the otherwise resistant tumor cells.  相似文献   
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In order to evaluate the influences of serum PTH assay in the various concentrations of serum calcium, we divided into three groups which serum calcium had below 8.0 mg/dl, 8.2 mg/dl to 9.8 mg/dl and above 10.0 mg/dl at random samples and assayed PTH in serum sample, using various kits of PTH assay obtained from commercial sources. Our results suggested that the measurement of serum PTH influenced by the concentration of serum calcium and therefore, should be taken an attention of serum calcium in each sample.  相似文献   
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Alternating copolymerization of butadiene with several α-olefins and of isoprene with propylene were investigated by using a mixture of VO(Acac)2, Et3Al, and Et2AlCl as catalyst. The alternating copolymerization ability of the olefins decreases in the order, propylene > 1-butene > 4-methyl-1-pentene > 3-methyl-1-butene. The study on the sequence of the copolymer of isoprene with propylene by ozonolysis reveals that the polymer chain is reasonably expressed by the sequence \documentclass{article}\pagestyle{empty}\begin{document}$ \rlap{--} [{\rm CH}_{\rm 2} \hbox{--} {\rm CH} \hbox{=\hskip-1pt=} {\rm C(CH}_{\rm 3}) \hbox{--} {\rm CH}_{\rm 2} \hbox{--} {\rm CH(CH}_{\rm 3}) \hbox{--} {\rm CH}_{\rm 2} \rlap{--}]_n $\end{document}. NMR and infrared spectra indicate that the chain is terminated with propylene unit, forming a structure of ?C(CH3)? CH2? C(CH3)?CH2 involving a vinylene group.  相似文献   
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Alternating cooligomerization of isoprene with propylene has been investigated between ?30 and 0°C, VO(acac)2–Et3Al–Et2AlCl being used as catalyst. In the presence of an excess of propylene, 2,4,7-trimethyl-1,4-octadiene and 2,4-dimethyl-1,4-nonadiene are selectively formed. The formation is explained by the alternating coordination of isoprene and propylene to the vanadium. When triphenylphosphine or pyridine is added to the catalyst, the cooligomerization is suppressed while the formation of the dimer and trimer of isoprene is high.  相似文献   
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Bone metabolic markers were investigated in the male hemodialysis patients within and over 60 years old and the female hemodialysis patients within and over 50 years old. Our results indicated that bone metabolic markers were more increased in the lower values of serum estradiol in the male patients, but inversely were more enhanced in higher values of serum estradiol in the female patients.  相似文献   
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Vapor—liquid equilibrium data for the ternary ethanol—2-butanone—benzene system and its constituent binary systems at 298.15 K are presented. The results are correlated with the Wilson, original and modified UNIQUAC equations and the UNIFAC group contribution method.  相似文献   
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