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排序方式: 共有2050条查询结果,搜索用时 46 毫秒
991.
C Giardini M Galimberti G Lucarelli P Polchi E Angelucci D Baronciani B Erer D Gaziev A Piga F Di Gregorio MA Romeo A Mangiagli E Petrelli P Muretto 《Canadian Metallurgical Quarterly》1997,20(9):767-772
The standard modality of the treatment for the patients with T4 esophageal cancer, whose prognosis still remains quite poor, is not established yet. Salvage surgery for the T4 esophageal cancer following downstaging by neoadjuvant chemo-radiotherapy has become to be available. During the period from 1992 to 96, 30 patients with the suspected T4 esophageal cancer underwent chemoradiotherapy, which consisted of two courses of CDDP/5-FU with-sequential or concurrent 50-60Gy radiotherapy. Among them eleven patients became to be resectable by means of thoracotomy and laparotomy and pathological CRs were obtained in either primary lesions or lymph nodes. The longest survival term following surgery is 36 months. Three patients died of cancer recurrence including the organ metastasis and one died from pyothorax without cancer due to severe immunosuppression attributable to chemoradiation. Our results warrants further studies of neoadjuvant chemoradiotherapy for the patients with T4 esophageal cancer. 相似文献
992.
Towards a luxury uptake process via microalgae - Defining the polyphosphate dynamics 总被引:1,自引:0,他引:1
Microalgae in waste stabilization ponds (WSP) have been shown to accumulate polyphosphate. This luxury uptake of phosphorus is influenced by the wastewater phosphate concentration, light intensity and temperature, but the dynamics of how these factors affect luxury uptake with respect to time are not understood. With improved understanding of the dynamics of this mechanism and how it could be manipulated, a phosphorus removal process utilizing luxury uptake by microalgae might be developed. In this work, luxury uptake was investigated by chemical extraction of the acid-soluble and acid-insoluble fractions of polyphosphate in the microalgae. The results showed that the initial accumulation and subsequent utilization of both acid-soluble polyphosphate (ASP) and acid-insoluble polyphosphate (AISP) is a function of the wastewater phosphate concentration. It was found that light intensity influenced both the accumulation and utilization of ASP. The temperature influenced the accumulation of AISP. AISP is believed to be a form of phosphorus storage and ASP is involved in metabolism however, the results of this work show that ASP can also act as a short term form of phosphorus storage. To optimize luxury uptake by microalgae a ‘luxury uptake pond’ is proposed where the conditions the microalgae are exposed to can be manipulated. This ‘luxury uptake pond’ would be designed to expose the microalgae to a high phosphate concentration and high light intensity for a short period of time in order to achieve optimal polyphosphate accumulation. Subsequent harvesting would then remove the phosphorus rich microalgae from the system. 相似文献
993.
F D'Amore CA Buda A Magnano A Bottari P Consolo L Romeo A Giudice 《Canadian Metallurgical Quarterly》1998,19(11-12):475-477
The Authors report a case of spontaneous large gastric phytobezoar in an unoperated stomach and describe this pathology especially with regards to pathogenesis, diagnosis and endoscopic treatment. 相似文献
994.
L Zeitlmann T Knorr M Knoll C Romeo P Sirim W Kolanus 《Canadian Metallurgical Quarterly》1998,273(25):15445-15452
The Syk family tyrosine kinases play a crucial role in antigen receptor-mediated signal transduction, but their regulation and cellular targets remain incompletely defined. Following receptor engagement, phosphorylation of tyrosine residues within ZAP-70 and Syk is thought to control both kinase activity and recruitment of modulatory factors. We report here the characterization of novel mutants of ZAP-70 and Syk, in which conserved C-terminal tyrosine residues have been replaced by phenylalanines (ZAP YF-C, Syk YF-C). Both mutant kinases display a prominent gain-of-function phenotype in Jurkat T cells, as demonstrated by lymphokine promoter activation, tyrosine phosphorylation of potential targets in vivo, and elevated intracellular calcium mobilization. While the presence of p56-Lck was required for ZAP YF-C-induced signaling, Syk YF-C showed enhanced functional activity in Lck-deficient JCaM1 Jurkat cells. Our results implicate the C terminus of Syk family kinases as an important regulatory region modulating T cell activation. 相似文献
995.
A spectrum of tracheo-esophageal anomalies has been described in an adriamycin-treated model with common features to the human pattern. Tracheal agenesis was part of this spectrum. It is a rare congenital anomaly that has not been described in embryos. Virgin timed-pregnant Sprague-Dawley rats were injected with adriamycin i.p. at a dose of 2 mg/Kg on days 6-9 of gestation (plug day = day 0). Fetuses were recovered at term and histologic assessment of tracheo-esophageal anomalies was made. Also, embryos were removed on different gestational days and the embryology of these defects was analysed. Two out of sixty-two fetuses and nine out of 180 embryos were identified with tracheal atresia. Type III tracheal atresia was seen in the full-term fetuses with a tracheo-esophageal fistula arising from the origin of the left main bronchus. Day 13 embryos did not show normal tracheal development; instead, the lung buds developed from the ventral aspect of the foregut which continued to the stomach as a lower esophageal segment. A blind ending pouch was seen on the ventral aspect of the upper part of the foregut. The embryogenesis of tracheal atresia was similar to that of esophageal atresia except that the blind upper foregut pouch developed ventrally rather than dorsally. 相似文献
996.
997.
Hauber Mark E.; Clayton Nicola S.; Kacelnik Alex; Reboreda Juan C.; DeVoogd Timothy J. 《Canadian Metallurgical Quarterly》1999,113(5):1095
Cowbirds exhibit extensive variation in their social, territorial, and reproductive behaviors. Nissl-stained brain sections of specimens from a previous study (J. C. Reboreda, N. S. Clayton, & A. Kacelnik, 1996) were used to study the gross anatomy of a song control nucleus in 3 South American cowbirds (bay-winged, Molothrus badius; shiny, M. bonariensis; and screaming, M. rufoaxillaris). Cowbird high vocal center (HVC) volumes were consistently higher in males than in females in all 3 species. The largest HVC size of females found in bay-winged cowbirds is consistent with observations that females of this species, but not of the other 2 species, occasionally sing. The extent of the sexual dimorphism of relative HVC size was highest for the sexually dichromatic and promiscuous shiny cowbirds and smaller for the monochromatic and monogamous bay-winged and screaming cowbirds, suggesting that selection pressures associated with morphological traits and social systems are reflected in brain architecture. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
998.
One of the important challenges for biomass combustion in industrial applications is the fouling tendency and how it affects to the boiler performance. The classical approach for this question is to activate sootblowing cycles with different strategies to clean the boiler (one per shift, one each six hours,…). Nevertheless, it has been often reported no effect on boiler fouling or an excessive steam consumption for sootblowing. This paper illustrates the methodology and the application to select the adequate time for activating sootblowing in an industrial biomass boiler. The outcome is a control strategy developed with artificial intelligence (Neural Network and Fuzzy Logic Expert System) for optimizing the biomass boiler cleaning and maximizing heat transfer along the time. Results from an optimize sootblowing schedule show savings up to 12 GWh/year in the case-study biomass boiler. Extra steam generation produces an average increase of turbine power output of 3.5%. 相似文献
999.
Nicola Trivellin Matteo Meneghini Gaudenzio Meneghesso Enrico Zanoni Kenji Orita Masaaki Yuri Tsuyoshi Tanaka Daisuke Ueda 《Microelectronics Reliability》2009,49(9-11):1236-1239
The purpose of this work is an in depth reliability analysis of Blu-Ray InGaN laser diodes (LD) submitted to CW stress at different currents and temperatures. During reliability tests, LD devices exhibit a gradual threshold current increase, while slope efficiency is almost not affected by the ageing treatment. Furthermore we demonstrate that: (i) the degradation rate shows a linear correlation with stress current level; (ii) the Ith increase is correlated to the decrease in non-radiative lifetime (τnr); (iii) stress temperature acts as an accelerating factor for LD degradation; (iv) pure thermal storage does not significantly degrade LDs characteristics. 相似文献
1000.
Nicola Ghittori Andrea Vigna Piero Malcovati Stefano D’Amico Andrea Baschirotto 《Analog Integrated Circuits and Signal Processing》2009,59(3):231-242
In this paper, we propose a transmitter baseband architecture for the present and up-coming WLAN applications (IEEE 802.11a/g,
802.11n, 802.16), based on a 600-MS/s current-steering DAC with a passive output load, to perform the baseband signal processing,
avoiding the use of any active analog reconstruction filter. The DAC, fabricated in a 0.13-μm CMOS technology, consumes 2.4 mW
from a 1.2-V single supply voltage. The DAC exhibits 68 dB of SFDR at full-scale for a 12-MHz input signal frequency and 9.7 bits of full-scale dynamic range in the bandwith from dc to 10 MHz. 相似文献