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31.
The sustained growth of data traffic volume calls for an introduction of an efficient and scalable transport platform for links of 100 Gb/s and beyond in the future optical network. In this article, after briefly reviewing the existing major technology options, we propose a novel, spectrum- efficient, and scalable optical transport network architecture called SLICE. The SLICE architecture enables sub-wavelength, superwavelength, and multiple-rate data traffic accommodation in a highly spectrum-efficient manner, thereby providing a fractional bandwidth service. Dynamic bandwidth variation of elastic optical paths provides network operators with new business opportunities offering cost-effective and highly available connectivity services through time-dependent bandwidth sharing, energy-efficient network operation, and highly survivable restoration with bandwidth squeezing. We also discuss an optical orthogonal frequency-division multiplexing-based flexible-rate transponder and a bandwidth-variable wavelength cross-connect as the enabling technologies of SLICE concept. Finally, we present the performance evaluation and technical challenges that arise in this new network architecture.  相似文献   
32.
A real-time PCR method targeting a gene sequence encoding 16S rRNA processing protein, rimM, for specific detection of Streptococcus thermophilus was developed. The designed real-time PCR primers and probe were specific for S. thermophilus JCM20026, LMG6896, LMG18311, OJT101, OJT102 but not Enteroccocus spp., Lactococcus lactis subsp. lactis, and Streptococcus salivarius which are phylogenetically closely related to S. thermophilus and are difficult to identify using culture-based methods. The linear range of the developed real-time PCR method was from 2.7 to 8.6 log CFU ml?1 with an amplification efficiency of 96%. Minor differences (about 0.4 log CFU ml?1) were observed between counts of S. thermophilus obtained by culture and real-time PCR method in plain yoghurt and yoghurt containing fruits. Therefore, the developed real-time PCR method could be of potential application in specific detection and accurate enumeration of S. thermophilus in a wide range of dairy products.  相似文献   
33.
We describe a 60-year-old woman with leg pain. Although metastatic bone tumor and atypical cells mimicking signet-ring cells in the bone marrow picture were observed, systemic survey revealed no primary lesion. The patient died two months after admission from systemic progress of the disease. Autopsy revealed a small focus of adenocarcinoma within the right upper lobe of the lung and systemic metastases without any particular changes in the gastrointestinal tract. The tumor cells of the lung were diffusely positive for cytokeratin 7, whereas cytokeratin 20 immunoreactivity was weak and focal, and that supported the lung origin of the present tumor. Moreover, the tumor cells in the bone marrow showed a similar pattern in immunoreactivity. These findings suggest that cytokeratin 7 and cytokeratin 20 immunoreactivity is helpful for the premortem diagnosis of the metastatic tumor of unknown origin.  相似文献   
34.
Pore behavior as influenced by migration of an abnormal grain boundary was studied. The pore behavior during the discontinuous growth of hot-pressed spinel (MgAl2O4) — whether the pore can move attached to the grain boundary — is particularly governed by the pore size and the matrix grain size. These phenomena can be understood from the interaction between the pore and the abnormal grain boundary.  相似文献   
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36.
Summary Introduction of isocyanate (NCO) group onto carbon black surface was achieved by the treatment of carbon black with toluene-2,4-diisocyanate. In addition, carbon black having acyl azide (CON3) group, a precursor of NCO group, was prepared by the reaction of COCl or COOCOOC2H5 group on carbon black with NaN3. The CON3 group on carbon black was relatively stable at below 20°C but readily decomposed to NCO group by heating (Curtius rearrangement). By the reation of NCO group on carbon black with hydroxyl group of polymers, such as polypropylene glycol, polyethylene glycol, and polyvinyl alcohol, these polymers were found to be grafted onto carbon black.  相似文献   
37.
To clarify the structure and function of the airways in Mycobacterium avium-intracellulare (MAI) infection, we performed pulmonary function tests and high-resolution computed tomography (HRCT) of the thorax in female patients 61 +/- 9 yr of age (n = 12) with pulmonary MAI infection without predisposing lung disease and compared their data with those of normal female volunteers 54 +/- 8 yr of age (n = 9). We calculated the E/I ratio, i.e., the average ratio of HRCT number at full expiration to that at full inspiration, as an index for the evaluation of air trapping distal to the small airways. Patients showed significant increases in residual volume and slope of phase III (DeltaN2) of the single-breath nitrogen test, and significant decreases in flow at 50 and 25% of FVC, suggesting hyperinflation and obstruction of the small airways. HRCT of patients revealed the small nodules and ectasis of bronchioles and small bronchi located mainly in segments (S) S2, S3, S4, and S5. The E/I ratio was significantly elevated in patients, and especially higher in the upper lung field than in the lower lung field, suggesting air trapping distal to the small airways. The difference of E/I ratio between the upper and lower field is probably related to the segmental distribution of CT abnormalities. These findings suggest that MAI infection can lead to air trapping distal to the small airways.  相似文献   
38.
OBJECTIVE: To evaluate the incidence of non-specific granulomatous prostatitis (GP) in our series of prostate biopsies and to verify whether there were differences in the features of DRE, PSA and ultrasound findings in patients with GP and patients with prostate cancer that could be used as clinical indications in GP diagnosis. MATERIAL AND METHODS: Between 1994 and 1996, 835 patients with prostatic syndromes underwent echoguided transrectal biopsy. Neoplasia was diagnosed in 323 (39%) patients, non-specific GP in 11 (1.5%), whereas no malignancy signs were found in the remaining 501 (59.7%). A retrospective comparison of DRE features, PSA levels and the existence of echographic nodes was conducted between cancer patients and GP patients. RESULTS: 55% GP patients had suspicious DRE; in 64% at least one node with different echogeneicity was identified in the transrectal ultrasound, and the mean PSA value was 17.3 ng/ml. When they were compared to the group of patients with prostate cancer, no significant differences were found. CONCLUSION: In our experience we have not found any specific feature in DRE. PSA levels or ultrasound examination that allows to differentiate GP from prostate cancer. Transrectal biopsy of the gland is essential for the differential diagnosis of both entities.  相似文献   
39.
PURPOSE: To clarify the contrast enhanced CT features and anatomic distribution of the disseminated vs non-disseminated tuberculosis (TB) involving abdominal lymph nodes. MATERIALS AND METHODS: The contrast enhanced CT findings of abdominal lymphadenopathy in 25 patients, including disseminated TB associated with miliary TB of the lung (n = 5) and non-disseminated TB (n = 20), were retrospectively evaluated in a blind review to assess our criteria of morphology, density and location of the involved lymphadenopathy. RESULTS: The enhancement patterns of disseminated TB were not different from those of non-disseminated TB. Ninety-six percent of the patients had peripheral rim enhancement, and 60% showed a multilocular appearance. The enlarged lymph nodes of TB were less than 4 cm in diameter. Lymphadenopathy caused by hematogenous dissemination often accompanied splenic involvement showing multiple low-density foci in the spleen. The predominant sites of lymphadenopathy of disseminated TB were hepatoduodenal ligamentous, hepatogastric ligamentous, mesenteric, and both upper and lower portions of the retroperitoneal lymph nodes, whereas non-disseminated TB mainly involved hepatoduodenal ligamentous, hepatogastric ligamentous, mesenteric and upper retroperitoneal lymph nodes, excluding the lower retroperitoneal lymph nodes. By combining contrast enhancement patterns and the anatomic distribution of lymphadenopathy shown on the contrast enhanced CT images, reviewers made a correct diagnoses of tuberculosis in 94%, of cases, with a specificity of 95% and sensitivity of 92%. CONCLUSION: Contrast enhanced CT patterns correlate well with the pathologic features of tuberculous lymphadenopathy. A different anatomic distribution between disseminated and non-disseminated TB involving the lower retropentoneal lymph nodes was recognized in this study.  相似文献   
40.
The anisotropic development is studied of mesophase pitches prepared from modified ethylene tar (ETP) using AlCl3, of fractions separated by benzene, tetrahydrofuran (THF) and pyridine, and of mixed fractions, to find structural factors affecting fusibility and optical anisotropy of mesophase pitch. Annealing was carried out at 360° C for 10 min. Each fraction developed a unique optical anisotropy quite different from that of the parent mesophase pitch. The lightest fraction (soluble in benzene) was highly fusible with small numbers of small anisotropic spheres. The heaviest fraction (insoluble in pyridine) was infusible and exhibited a total mosaic anisotropy. In contrast, mixed fractions behaved like the parent mesophase pitch in terms of liquid crystal behaviour. The extent of anisotropy and fusibility after annealing were strongly dependent on the preparatory conditions of the parent mesophase pitch. The fusibility of mixed fractions is ascribed to the dissolving ability of the fusible fraction and the solubility of the infusible fraction at the annealing temperature. Small molecules in the lighter fractions also contribute to anisotropy when they are located in interlayer positions between the larger aromatic molecules which constitute liquid crystals. Such co-operative properties of constituent molecules of the mesophase pitch can be described in terms of a practical compatibility.  相似文献   
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