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131.
Doppler data were obtained from a normal carotid, popliteal, and radial artery. It was found that the results of a digital zero-crossing counter-mean frequency estimate and the first moment of the FFT (fast-Fourier-transform)-generated spectra were comparable for high signal-to-noise ratio (SNR), as in the case of the carotid arterial waveform. However, the digital zero-crossing with thresholding was a more accurate representation of the expected velocity-vs.-time waveforms in the case of low-SNR Doppler obtained from the popliteal and radial arteries.<> 相似文献
132.
RJ Cote DP Houchens CL Hitchcock AD Saad RG Nines JK Greenson S Schneebaum MW Arnold EW Martin 《Canadian Metallurgical Quarterly》1996,77(4):613-620
BACKGROUND: The detection of locally-disseminated disease is one of the principal goals of oncologic surgery. For this study, a hand-held, gamma-detecting probe was used intraoperatively to assess the extent of colorectal carcinoma in patients previously injected with radiolabeled antibody to the TAG-72 antigen (CC49); this technique is known as Radioimmunoguided Surgery (RIGS) (Neoprobe Corporation, Dublin, OH). RIGS-positive areas (i.e. those with increased signal over background) have previously been shown to contain carcinoma in a high proportion of cases. However, some RIGS-positive areas had no tumor detectable by clinical examination or routine histopathologic analysis. This study was undertaken to determine if the presence of occult metastases might account for this disparity. METHODS: A total of 57 regional lymph nodes (LN), resected from 16 patients with primary (9) or recurrent (7) colorectal carcinoma, were studied. The patients were injected with 125I labeled CC49 murine monoclonal antibody approximately 3 weeks prior to surgery. After routine histologic evaluation, the LN were analyzed for occult metastases; paraffin sections were cut at 5 levels (50 micron apart) and were examined by histology (hematoxylin and eosin stain [H & E]) and by immunohistochemistry (IHC) with a cocktail of monoclonal antibodies to cytokeratins. RESULTS: Fifty-seven LN were included in this study; 17 were H & E-positive (i.e., contained tumor by routine histologic examination [overt tumor]), while 40 LN were H & E-negative (i.e., no evidence of tumor after routine histologic examination). Thirty-nine LN were RIGS-positive, but only 14 of these were H & E-positive. Of the 25 RIGS-positive/H & E-negative LN, 10 (40%) demonstrated the presence of occult metastases after serial section/IHC analysis. Thus, a total of 27 LN contained metastatic carcinoma (17 overt, 10 occult); routine histologic analysis was able to identify tumor in only 17 of these 27 LN (63%), while the probe signaled the presence of tumor in 24 of these LN (89%). None of the RIGS-negative/H & E-negative LN were found to have occult metastases (0/15). Specific immunoreactivity with CC49 antibody was observed in 5 of 15 RIGS-positive/H & E-negative LN in which no tumor could be identified by any method (histopathology or IHC. CC49 immunoreactivity was not observed in 15 RIGS-negative/H & E-negative LN. CONCLUSIONS: The finding of a RIGS-positive LN had a significant association with the presence of tumor cells (P < 0.05). In this study, the RIGS procedure was more sensitive than clinical or histopathologic examination in detecting the regional spread of a tumor. Furthermore, in LN that showed no evidence of tumor by routine histopathologic examination, a positive RIGS reading was significantly associated with the presence of occult LN metastases (P < 0.01). This study is the first to demonstrate the detection of histologically occult tumor by a remote imaging device. RIGS assessment is a highly sensitive method for detecting occult tumor deposits, and may guide therapeutic intervention in patients with colorectal carcinoma. 相似文献
133.
Direct compression offers a simple route to generate pharmaceutical dosage units and is core to the growing arena of continuous manufacturing. However, direct compression can be untenable for some active materials. This paper will outline three specific challenges API’s can present to direct (active pharmaceutical ingredients) compression. The first involves API’s having exceedingly high aspect ratio (“needles”) or small particle size resulting in low bulk density and poor flow properties. Two additional cases are relatively newer challenges to direct compression driven by the growing need for solubility enhancing formulations, and involve nano-crystalline materials and spray dried amorphous dispersions. Multiple approaches for managing high aspect ratio or micronized API’s have been implemented during the crystallization process or via particle coating downstream from API isolation. Fewer options have been reported for the successful conversion of nano-crystalline materials or spray dried amorphous dispersions into materials amenable to direct compression as these materials offer another specific set of challenges. One route that has not been explored that stands to allow continuous drug product processing across a broader product portfolio involves evaluating opportunities at the drug substance/drug product interface. Here, the options achieved through targeted introduction of excipients to the drug substance processing steps during product precipitation and/or isolation from a product slurry are discussed. This approach introduces new opportunities for designing multicomponent particles through productive and inherently continuous processes. This also offers a longer-term potential route to integrate across continuous drug substance processing to continuous drug product processing. 相似文献
134.
Bornstein Marc H.; Cote Linda R.; Haynes O. Maurice; Hahn Chun-Shin; Park Yoonjung 《Canadian Metallurgical Quarterly》2010,46(6):1677
Knowledge of child rearing and child development is relevant to parenting and the well-being of children. Using a sociodemographically heterogeneous sample of 268 European American mothers of 2-year-olds, we assessed the state of mothers' parenting knowledge; compared parenting knowledge in groups of mothers who varied in terms of parenthood and social status; and identified principal sources of mothers' parenting knowledge in terms of social factors, parenting supports, and formal classes. On the whole, European American mothers demonstrated fair but less than complete basic parenting knowledge; age, education, and rated helpfulness of written materials each uniquely contributed to mothers' knowledge. Adult mothers scored higher than adolescent mothers, and mothers improved in their knowledge of parenting from their first to their second child (and were stable across time). No differences were found between mothers of girls and boys, mothers who varied in employment status, or birth and adoptive mothers. The implications of variation in parenting knowledge and its sources for parenting education and clinical interactions with parents are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献