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21.
Molecular biology of mouse and chicken retroviruses had identified oncogenes and provided a revolutionary concept in understanding of cancers. A human retrovirus was established during 1980–1982 in linkage with a unique human leukemia, concurrently in Japan and USA. This review covers our efforts on the discovery of new retrovirus, Human T-cell Leukemia Virus Type 1 (HTLV-1), first introducing to a new class of retroviruses with a unique regulatory factors, Tax and Rex. Then it is followed by analyses of molecular interaction of the vial Tax with cellular machineries involved in the pathogenesis of Adult T-cell Leukemia (ATL). And then a probable mechanism of pathogenesis of ATL is proposed including recent findings on HBZ after our efforts.  相似文献   
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Currently nanosystems composed of polynucleotides and lipid vesicles (nanolipoplexes) are considered to be promising tools for gene therapeutics. Successful in vivo application of these vectors depends on their physicochemical, technological and biological characteristics including morphology, size distribution, molecular interactions and stability. Anionic nanoliposomes (DPPC:DCP:CHOL) were prepared by two different techniques, namely the conventional thin-film hydration method followed by extrusion, and the heating method (HM), in which no volatile solvent or detergent is used. A non-viral and non-cationic gene transfer vector was constructed by incorporating plasmid DNA (pcDNA3.1/His B/lacZ) to the HM-nanoliposomes by the electrostatic mediation of Ca2+ ions. Transfection efficiency of the nanolipoplexes was evaluated using a human bronchial epithelial cell line (16HBE14o-) in the presence of serum. Particle characterisation, stability of the formulations and lipid–DNA interaction studies were performed using transmission electron microscopy (TEM) and light scattering. TEM pictures of nanolipoplexes showed presence of two to four closely packed vesicles with signs of fusion. Efficient delivery of plasmid DNA and subsequent β-galactosidase expression was achieved using the anionic nanolipoplexes. Transfection efficiency increased with lipid:DNA ratio up to 7:1 (w/w), where transfection efficiency was 12-fold higher than in untreated cells. Further increase in lipid ratio decreased transfection. These nanolipoplexes appear to be safe, stable and efficient in the protection and delivery of DNA to different cells and tissues.  相似文献   
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The purpose of this study was to investigate if there was an effect of task on determination of maximum phonational frequency range (MPFR). Two tasks commonly used to elicit MPFR in clinical voice evaluations were compared. Normal adult females (N = 30) were examined. No statistically significant effect of task was found. Both tasks (glissando and discrete-step) were found to have a high positive correlation (0.84). Implications of the use of one task for determination of maximum phonational frequency range are discussed, as is the possibility of a task effect on determination of other voice parameters.  相似文献   
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Medical imaging is a vital component of high intensity focused ultrasound (HIFU) therapy, which is gaining clinical acceptance for tissue ablation and cancer therapy. Imaging is necessary to plan and guide the application of therapeutic ultrasound, and to monitor the effects it induces in tissue. Because they can transmit high intensity continuous wave ultrasound for treatment and pulsed ultrasound for imaging, dual-mode transducers aim to improve the guidance and monitoring stages. Their primary advantage is implicit registration between the imaging and treatment axes, and so they can help ensure before treatment that the therapeutic beam is correctly aligned with the planned treatment volume. During treatment, imaging signals can be processed in real-time to assess acoustic properties of the tissue that are related to thermal ablation. Piezocomposite materials are favorable for dual-mode transducers because of their improved bandwidth, which in turn improves imaging performance while maintaining high efficiency for treatment. Here we present our experiences with three dual-mode transducers for interstitial applications. The first was an 11-MHz monoelement designed for use in the bile duct. It had a aperture that was cylindrically focused to 10 mm. The applicator motion was step-wise rotational for imaging and therapy over a 360°, or smaller, sector. The second transducer had 5-elements, each measuring for a total aperture of . It operated at 5.6 MHz, was cylindrically focused to 14 mm, and was integrated with a servo-controlled oscillating probe designed for sector imaging and directive therapy in the liver. The last transducer was a 5-MHz, 64-element linear array designed for beam-formed imaging and therapy. The aperture was with a pitch of 0.280 mm. Characterization results included conversion efficiencies above 50%, pulse-echo bandwidths above 50%, surface intensities up to , and axial imaging resolutions to 0.2 mm. The second transducer was evaluated in vivo using porcine liver, where coagulation necrosis was induced up to a depth of 20 mm in 120 s. B-mode and M-mode images displayed a hypoechoic region that agreed well with lesion depth observed by gross histology. These feasibility studies demonstrate that the dual-mode transducers had imaging performance that was sufficient to aid the guidance and monitoring of treatment, and could sustain high intensities to induce coagulation necrosis in vivo.  相似文献   
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Nanoparticle plasmonics is a rapidly emerging research field that deals with the fabrication and optical characterization of noble metal nanoparticles of various size, shape, structure, and tunable plasmon resonances over VIS-NIR spectral band. The recent simultaneous advances in synthesis, characterization, electromagnetic simulation, and surface functionalization of plasmonic nanoparticles by biospecific molecular probes have led to a perfect publication storm in discoveries and potential biomedical applications of plasmon-resonant nanoparticle bioconjugates. Here, we present an overview of these topics. First, we discus basic wet-chemical routes to fabricate conjugates of gold, silver, or composite particles with controllable size, shape, structure and with surface functionalization by biospecific molecules. Second, we consider the single-particle dipole and multipole optics and coupled plasmonic nanoparticle arrays. Finally, we discus application of plasmonic bioconjugates to such fields as homogeneous and solid-phase assays, biomedical sensing and imaging, biodistribution and toxicity aspects, drug delivery and plasmonic photothermal therapy.  相似文献   
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二氢卟吩e~6-6-酰胺衍生物的合成   总被引:2,自引:0,他引:2  
章玲  许德余 《有机化学》1999,19(4):424-430
首次报道了以蚕沙叶绿素初提物为基础原料,经酸降解得到含焦脱镁叶绿酸a和脱镁叶绿酸a的混合物,不经分离直接与胺类反应使脱镁叶绿酸a的戊酮环(V)裂开,合成得11种二氢卟吩e~6-6-酰胺衍生物。提供了一种合成二氢卟吩酰胺的新方法。  相似文献   
29.
The effective voice clinician has always had to borrow from various disciplines: voice science, otolaryngology, psychology, and speech-language pathology. Such eclecticism requires, however, that the clinician integrate the perspectives of these various disciplines into some kind of theoretical clinical bias. One bias might be that with greater use of instrumentation in voice therapy, the voice clinician must not substitute data collection for attending to the feelings of the patient. By using the clinical input from various disciplines, for example, voice clinicians might develop a useful clinical perspective that vocal hyperfunction is one of the primary causes of many voice disorders. Consequently, from such a clinical view might come a treatment perspective that can clearly define the problem (too much effort while speaking) and offer a rationale for voice remediation.  相似文献   
30.
自由电子激光这种新型光源非常适合于医学应用。通过对医用自由电子激光器的简要介绍,探讨了自由电子激光与人体组织的相互作用及其在医学上的应用前景。  相似文献   
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