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31.
Analysis of the S-phase fractions (SPF) measured by in vitro thymidine labeling, morphological appearances, and estrogen receptor (ER) assays of primary invasive breast carcinomas demonstrated several interrelationships. Lobular, mucinous, tubular, and adenocystic carcinomas consistently had low SPF and were usually positive for ER. The same was true for the carcinomas of no special histologic type [the not otherwise specified (NOS) group of E. R. Fisher including "infiltrating ductal" and undifferentiated carcinomas] with minimal anaplasia. Medullary, atypical medullary, and morphologically unclassifiable carcinomas with marked nuclear anaplasia nearly always had high SPF and were usually negative for ER. High SPF was associated with advanced stages of carcinoma initially or with early recurrence following mastectomy. 相似文献
32.
WL George BD Kirby VL Sutter DM Citron SM Finegold 《Canadian Metallurgical Quarterly》1981,3(3):599-626
Twenty infrequently reported species of gram-negative anaerobic bacilli other than Fusobacterium nucleatum, Fusobacterium necrophorum, and members of the genus Bacteroides were studied with regard to their role in infection and their susceptibility to antimicrobial agents. In addition, the literature regarding the recovery of these organisms from both the normal flora and infections of humans was reviewed. During a six-year period at the Wadsworth Clinical Anaerobic Bacteriology Research Laboratory (Veterans Administration Wadsworth Medical Center, Los Angeles, Calif.), 39 (6%) of 679 specimens obtained from anaerobic infections yielded "other gram-negative anaerobic bacilli" (OGNAB). Fusobacterium naviforme, Fusobacterium gonidiaformans, Fusobacterium varium, Fusobacterium mortiferum, and Fusobacterium russii were the most commonly isolated OGNAB. Most of the OGNAB tested were resistant to erythromycin, and most strains, except for F. varium, were susceptible to beta-lactam antibiotics and clindamycin. Chloramphenicol and metronidazole were active against all strains of OGNAB tested. Certain Fusobacterium species are undoubtedly previously unrecognized members of the normal flora of the oropharynx, upper respiratory tract, or urogenital tract and may be present in infections derived from these floras. 相似文献
33.
The combined efforts of the AFD supplier and end-user have resulted in an extremely reliable electrical adjustable speed drive system. Almost three years into the run of the first unit, all parties are confident of the ability to meet the five-year run target that was identified at the outset. The redundancy of the power cells in this particular design, together with the neutral shift control has practically eliminated the power components as a source of operational failure. Future development efforts will include applying redundancy and fault tolerance to the drive control processor to further enhance system reliability. 相似文献
34.
Solvent vapor treatment controls surface wettability in PMMA femtosecond-laser-ablated microchannels
Carmela De Marco Shane M. Eaton Rebeca Martinez-Vazquez Stefano Rampini Giulio Cerullo Marinella Levi Stefano Turri Roberto Osellame 《Microfluidics and nanofluidics》2013,14(1-2):171-176
A solvent vapor treatment was applied to femtosecond-laser-ablated microchannels in PMMA to selectively restore the original hydrophilic wetting behavior of the pristine surface. The hydrophobic surface of the microchannels from the submicron porosity induced by ablation becomes smoother and more transparent after the treatment. This simple and low-cost method, together with suitable masking, can produce wettability patterns that may be exploited to develop passive microfluidic elements such as valves and mixers. 相似文献
35.
Eaton S. Lothrop Jr. 《History of Photography》2013,37(3):271-272
Abstract Images and Enterprise is one of the books in the Johns Hopkins Studies in the History of Technology Series and, as such, is a study of the American photographic industry within the overall field of technology. It covers the period 1839-1925, and deals with technical, business and, to a lesser extent, social aspects. These are traced from the industry's disorganized, diffuse beginnings to the point where the market became dominated by a few highly organized, technologically oriented fmus. When the daguerreotype process was introduced in 1839, its practitioners and even their immediate suppliers were compelled to look to a number of sources for the necessary materials: cabinet makers supplied camera boxes, chemical firms the required elements and compounds, miniature-case makers produced containers for the finished pictures, and the brass industry manufactured the silver-coated copper plates. The need for general supply houses was not immediately perceived. Much had to be imported, and European producers played a big role during the early years in providing lenses, fine chemicals and plates for American users. 相似文献
36.
Ordinarily people do not make special purpose trips to acquire goods like gasoline or groceries but instead buy them as the need arises in the course of their daily lives. Such goods are commonly called convenience goods. We modify Hotelling??s model of spatial competition so that we can analyze the price equilibrium of duopolists that retail a convenience good. Certain features of the duopolists?? demand functions suggest that price competition is more severe in the convenience goods model than in the Hotelling model. The same features complicate the analysis because they mean that a pure strategy price equilibrium does not exist for many locational configurations. Although we are not able to find the mixed strategy price equilibrium analytically, we do present some numerical results on equilibrium prices that broadly confirm this suggestion. We also provide a more general product differentiation interpretation of the convenience good model. 相似文献
37.
Leonard K. Eaton 《The Journal of Architecture》2013,18(4):315-346
This paper traces the development of Frank Lloyd Wright's ideas on the place of the concrete column and slab in architecture. It deals with his first employment of the slab at Unity Temple (Oak Park, 1904) and his use of the form in residential projects during the next few years. It surveys American literature on concrete construction and briefly analyses the contribution of Claude A.P. Turner and the employment of the Turner system in two Chicago buildings that Wright would have known. It discusses his project for the San Francisco Call (1912) and the use of the Barton system in the Richland Center warehouse for A.D. German (1915). It further discusses his first probable knowledge of the more sophisticated concrete slabs of Maillart, published in 1926, and of Maillart's invention of a proto lily-pad capital. This capital is also to be seen in Wright's champagne glass designed for Leerdam (1930) and in his project for the Salem Capitol Journal of 1931. Finally it is argued that the much admired lily-pad columns at the Johnson Wax office building (Racine, 1937-39) are really a series of three-hinged bents rather than shell construction. 相似文献
38.
The jaw fat of the Atlantic bottlenose dolphin (Tursiops truncatus) contains unusual wax esters which can be separated into short chain (<C24) and long chain (>C24) fractions by thin layer chromatography. The short chain wax esters (28 wt. %) have been characterized as a 72∶24∶4 mixture
of isovaleroyl, isobutoryl, and 2-methylbutyrol, esters of C14–C18 n- and iso-alcohols. The intact <C24 esters have been resolved into individual molecular species by gas liquid chromatography on open-tubular polyester columns.
The long chain wax esters (12 wt. %) contain C10–C22 n- and iso-acids esterified to the same C14–C18 n- and iso-alcohols. Gas liquid chromatography of the intact, hydrogenated >C24 esters on a short JXR column has characterized them according to carbon number and the number of methyl branches they contain. 相似文献
39.
冷板辐射加置换通风空词系统在保证室内环境的前提下比常规全空气空调系统节能,但在天气湿热的香港地区应用会出现冷板凝露现象,且采用置换通风方式,风量有限从而影响热舒适性.本文将干式风机盘管系统与独立除湿通风系统组合应用于香港地区办公楼,干式风机盘管系统处理室内显热负荷,独立除湿通风系统承担室内湿负荷和室外全热负荷.采用EnergyPlus软件模拟分析了该空调系统在香港地区某办公楼中的使用性能,结果表明该系统能很好地控制室内温、湿度,特别是湿度,与常规全空气空调系统相比,全年节能达10.3%. 相似文献
40.
The unique characteristic of subcritical water is its widely tunable physical properties. For example, the polarity (measured by dielectric constant) of water is significantly decreased by raising water temperature. At temperatures of 200-250 °C (under moderate pressure to keep water in the liquid state), the polarity of pure water is similar to that of pure methanol or acetonitrile at ambient conditions. Therefore, pure subcritical water may be able to serve as the mobile phase for reversed-phase separations. To investigate the retention behavior in subcritical water separation, the retention factors of BTEX (benzene, toluene, ethylbenzene, and m-xylene), phenol, aniline, and their derivatives have been determined using subcritical water, methanol/water, and acetonitrile/water systems. Subcritical water separations were also performed using alumina, silica-bonded C18, and poly(styrene-divinylbenzene) columns to study the influence of the stationary phase on analyte retention under subcritical water conditions. 相似文献