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51.
We had 4 cases with multiple ventricular septal defects (VSDs) in complexed congenital heart disease. One of four had two separate VSDs detected by two dimensional echocardiography before operation. Second of four had additional infundibular muscular VSD which was detected by echocardiography in the intensive care unit (ICU) after patch closure of a perimembranous VSD. The third case had two additional VSDs of inlet muscular and subaortic septum detected by transesophageal and direct echocardiography during reoperation, beside a subpulmonary VSD which was originally diagnosed before Jatene operation for double outlet right ventricle. The fourth case had multiple trabecular muscular VSDs diagnosed by postoperative angiography soon after Rastelli operation. Since these additional multiple VSDs compromise the postoperative hemodynamics if those are unrecognized, it is indispensable to detect all VSDs before operation, using transthoracic and transesophageal echocardiography.  相似文献   
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In order to investigate the optimum transmission bit-rate for teletext signals in the 525-line television system, laboratory and field tests were carried out using binary NRZ digital data signals of several bit-rates to 5.73 Mbit/s ( 364fH, 8/5fsc). In these tests, the bit-errors and eye-openings of PN signals were measured and subjective evaluation of teletext signals was also made under various receiving conditions. The results have indicated that a digital data signal of 5.73 Mbit/s could be utilized for teletext in the 525-line television system. The Japanese teletext system now being developed employs this bit-rate for transmitting and displaying the signals.  相似文献   
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The conventional methods (CM) of intraarterial (IA) chemotherapy for inflammatory breast cancer were catheterizations from superior epigastric and brachial artery under general anesthesia. Since 1997, we selected the Seldinger's methods (SM) for ten cases of the disease to control local effects and simplify the technique. Complications of the SM were slight, and side effects were equal to those with CM. The postoperative pathological findings of the SM showed the direct effects of chemotherapy to tumor cells (degenerative and necrotic changes) as compared with the embolism-like effects of CM. But the overall histological effects of chemotherapy by SM were almost equal to those for CM. The strong points of the SM were as follows: 1) More selective IA chemotherapy is available, 2) one can find the passage of the aim vessels and no trouble related to catheter, 3) general anesthesia is not necessary, and the techniques are simple, 4) the wounds are not remarkable. The disadvantages are as follows: 1) Patients must rest the day of IA chemotherapy, 2) in 20% of the procedures, one can not search the vessels, and 3) in 4 cases complications of stiffness of Mj or Mn pectral muscles were found. In future, we expect more effective results by dose escalation or combination chemotherapy.  相似文献   
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Zinc pyrithione has been used in anti-dandruff shampoos and in anti-fouling paint on ships. However, little is known of its mode of action. We characterized the effects of sub-lethal concentrations of zinc pyrithione (Zpt) on Saccharomyces cerevisiae using DNA microarrays. The majority of the strongly upregulated genes are related to iron transport, and many of the strongly downregulated genes are related to the biosynthesis of cytochrome (heme). These data suggest that Zpt induces severe iron starvation. To confirm the DNA microarray data, we supplemented cultures containing Zpt with iron, and the growth of the yeast was restored significantly. From these results, we propose that the principal toxicity of zinc pyrithione arises from iron starvation.  相似文献   
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ABSTRACT

The thermal-neutron capture cross-section (σ0) and resonance integral (I0) were measured for the 135Cs(n,γ)136Cs reaction by an activation method and mass spectrometry. Because of difficulty in the preparation of pure 135Cs samples, we used 135Cs contained as an impurity in a normally available 137Cs standard solution. An isotope ratio of 135Cs and 137Cs in a standard 137Cs solution was measured by mass spectrometry to quantify 135Cs. Cesium-135 impurity along with the 137Cs standard solution was irradiated at the hydraulic conveyer of the research reactor in the Institute for Integral Radiation and Nuclear Science, Kyoto University. Wires of Co/Al and Au/Al alloys were used as neutron monitors to measure thermal-neutron fluxes and epi-thermal Westcott’s indices at an irradiation position. A gadolinium filter was used to measure the σ0, and a value of 0.133 eV was taken as the cut-off energy. Gamma-ray spectroscopy was used to measure induced activities of 137Cs, 136Cs and monitor wires. On the basis of Westcott’s convention, the σ0 and I0 values were derived as 8.57 ± 0.25 barn, and 45.3 ± 3.2 barn, respectively. The value of σ0 obtained in the present study agreed within the limits of uncertainties with the past-reported value of 8.3 ± 0.3 barn.  相似文献   
59.
Uehara H  Osada T  Ikai A 《Ultramicroscopy》2004,100(3-4):197-201
Asymmetric localizations of cellular proteins and mRNAs are important for cell functions such as division, differentiation and development. The localization of specific mRNA generates cell polarity by controlling the translation sites of specific proteins and thereby restricting their locations to appropriate cellular regions. We have previously reported a novel method based on atomic force microscopy (AFM) for examining gene expression in a single living cell without killing or destroying it. An AFM tip was inserted into a living cell to extract mRNAs, which were analyzed after multiplication by RT-PCR and quantitative PCR. By applying this method, in this study we performed quantitative measurement of mRNA at different loci within individual living cells.  相似文献   
60.
BACKGROUND & OBJECTIVE: Although thoracoscopic laser ablation therapy has been hailed as an effective surgical treatment for diffuse emphysema, no one has as yet made an in-depth study of the efficacy of this treatment. This investigation was undertaken to research the effects of laser pneumoplasty on an animal model of emphysema. STUDY DESIGN/MATERIALS AND METHODS: Eight weeks after elastase treatment, the rats' left lungs were irradiated using contact Nd:YAG laser. Pulmonary function tests were performed 4 weeks after irradiation and the lungs were prepared for histologic examination. RESULTS: Dense fibrous scars beneath the pleura were observed at 4 weeks after irradiation. Although mean linear intercept values of irradiated lungs were not much lower than those in the non-irradiated elastase-treated group, laser irradiation caused a significant decrease in lung volume. While there was no significant difference in quasistatic compliance, elastic recoil pressure of the lung increased to control levels at total lung capacity volume. CONCLUSION: We conclude that laser therapy does not cause normalization of compliance, or improvement in the deeper part of the emphysematous lung, but rather a peripheral volume reduction and "encasement effect" on the lungs as a result of fibrotic scars.  相似文献   
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