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31.
The herpes simplex virus-1 (HSV-1) capsid shell has 162 capsomers arranged on a T = 16 icosahedral lattice. The major capsid protein, VP5 MW = 149,075) is the structural component of the capsomers. VP5 is an unusually large viral capsid protein and has been shown to consist of multiple domains. To study the conformation of VP5 as it is folded into capsid promoters, we identified the sequence recognized by a VP5-specific monoclonal antibody and localized the epitope on the capsid surface by cryoelectron microscopy and image reconstruction. The epitope of mAb 6F10 was mapped to residues 862-880 by immunoblotting experiments performed with (1) proteolytic fragments of VP5, (2) GST-fusion proteins containing VP5 domains, and (3) synthetic VP5 peptides. As visualized in a three-dimensional density map of 6F10-precipitated capsids, the antibody was found to bind at sites on the outer surface of the capsid just inside the openings of the trans-capsomeric channels. We conclude that these sites are occupied by peptide 862-880 in the mature HSV-1 capsid.  相似文献   
32.
The photochemical deposition of phosphorus nitride film on InP substrates using an ArF excimer laser (wavelength = 193 nm) to decompose a mixture of PH3-NH3 gases and synthesise the film is presented. The deposition temperature can be reduced from 480°C used in the thermal-CVD technique to 300°C. The film deposited photochemically exhibits a much larger resistivity and lower leakage current than that obtained by the thermal-CVD technique at 300°C. The minimum interface state density measured by C/V curves is 1012 eV?l cm?2 at (Ec ? 0.3) eV.  相似文献   
33.
The relationship between Hornor's method for polynomial evaluation and a first-order recursive filter with error feedback (EFB) is described. It is shown that EFB is a useful technique for reducing the roundoff errors that occur in evaluating a function by polynomial approximation  相似文献   
34.
We report a rare case of adenoid basal carcinoma of the uterine cervix, unexpectedly found in a uterus resected for the treatment of cervical intraepithelial neoplasia (CIN) 3. The patient was a 47-year-old Japanese female. She received a total abdominal hysterectomy under a diagnosis of CIN 3 of the cervix. Grossly, there were no significant findings in the surgical specimens. Microscopically, in seven of the 12 blocks of the cervix examined, scattered small nests of uniform small cells, which extended 4 mm below the epithelial surface, with dark nuclei and scant cytoplasm were observed. Peripheral palisading as well as the formation of gland-like or acinar structures were noted. The latter were positive for mucicarmine. Stromal reaction was not obvious. There were also foci of squamous differentiation in some portions of the small nests. Occasional mitoses as well as large atypical cells were also seen in this area. Immunohistochemically, the foci of squamous differentiation were positive for carcinoembryonic antigen. The epithelial surface in other portions showed CIN 3 with crypt extension. Distinction between adenoid basal carcinoma of the cervix and other diseases, such as adenoid cystic carcinoma and squamous cell carcinoma with basaloid features, is important for clinical management because the clinical behavior of adenoid basal carcinoma is less malignant.  相似文献   
35.
Spontaneous rupture of the kidney is uncommon. We report a case of spontaneous rupture of the kidney due to a renal cell carcinoma. A 53-year-old man presented with right renal tumor. Computed tomography demonstrated a 70 mm right renal tumor which involved the entire upper pole of the kidney and extended into the renal vein. A few days later, the patient had sudden severe right flank pain. Computed tomography of the abdomen revealed a large perirenal hematoma of the right kidney. Angiography demonstrated no vascular abnormality. Nephrectomy was performed. The histological examination showed rupture of a renal cell carcinoma in the right kidney.  相似文献   
36.
Asymmetric tilt-angle-implanted lightly doped drain (LDD)-WNx -GaAs MESFETs with an optimized transconductance performance are discussed. A tilt-angle implantation is used to reduce the parasitic source resistance below the gate sidewall without increasing short- and narrow-channel effects. This leads to a transconductance increase of nearly 25% for submicrometer FETs while the gate-source capacitance increase is almost negligible. The influence of the implantation angle on the threshold voltage transconductance, and Schottky-barrier characteristics is reported  相似文献   
37.
Fabrication methods for low drive voltage and broad-band LiNbO3waveguide directional coupler optical modulator are described. Optical waveguides were prepared by conventionaly Ti in-diffusion into LiNbO3c-cut plate. To obtain wide-band frequency response, traveling wave electrodes were used. Electrode characteristic impedance measured by time domain reflectometry method coincided well with the calculated value by conformal mapping. Measured electrode conductor losses followed square root of frequency. To reduce electrode conductor losses, asymmetric and 3-μm thick Al electrodes were used. Directional coupler optical modulator frequency response was analyzed, using the phase difference average value along the propagation directions. Calculated value by this method coincided well with measured value obtained by a swept frequency technique. The characteristics of this modulator at the 1.317-μm wavelength are as follows: 100 percent modulation voltage is 4 V, extinction ratio is 17 dB, optical insertion loss is 5.4 dB, 3-dB bandwidth is 3.6 GHz, and rise time is about 400ps.  相似文献   
38.
Resveratrol 3-O-beta-D-glucopyranoside (1) has been isolated from the seeds of Erythrophleum lasianthum (Caesalpinioidae, Leguminosae), a South African plant used in traditional medicine, and has shown antiplatelet aggregation activity. The synthesis of 1, related hydroxystilbenes, and their glucosides has been undertaken to provide larger quantities, for further biological evaluation, and has been accomplished via Wittig reactions followed by glucosylation under phase transfer catalysis.  相似文献   
39.
Quaternary AlGaInAs quantum-well optical modulators operating at 1.55 μm are introduced and demonstrated for the first time. An electron-to-heavy-hole exciton absorption peak shift of over 600 Å is observed for a bias voltage of 6 V. An extinction ratio of 19 dB and high-speed operation over 4 GHz is obtained for this optical modulator  相似文献   
40.
We constructed a recombinant baculovirus expressing feline herpesvirus type I (FHV-1) gD in insect cells (Sf9 cells). The expressed product was identified as FHV-1 gD by a panel of monoclonal antibodies specific for the FHV-1 gD, and had an apparent molecular mass of approximately 49 kDa, which was less than that of the authentic FHV-1 gD. When the FHV-1 gD protein were expressed in Sf9 cells and CRFK cells in the presence of tunicamycin, the FHV-1 gD exhibited a molecular mass of 41 kDa. It was shown that the gD protein was transported to the surface of recombinant virus-infected Sf9 cells when examined by membrane-immunofluorescence analysis, and that the gD expressed on the surface of Sf9 cells adsorbed feline erythrocytes. Mice inoculated with a lysate of Sf9 cells expressing FHV-1 gD induced antibodies with virus-neutralizing and hemagglutination-inhibition activities. Therefore, the expressed gD appears to be biologically authentic. These data suggested that recombinant FHV-1 gD produced in Sf9 cells may be a useful immunogen as a feline vaccine.  相似文献   
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