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排序方式: 共有1015条查询结果,搜索用时 15 毫秒
61.
Carlos Eduardo de Ara jo Padilha Juliana Chris Silva de Azevedo Francisco Canind de Sousa J nior S rgio Dantas de Oliveira J nior Domingos Fabiano de Santana Souza Jackson Ara jo de Oliveira Gorete Ribeiro de Macedo Everaldo Silvino dos Santos 《中国化学工程学报》2018,26(12):2471-2476
In this study the potential of cloud point extraction formed by a non-ionic surfactant was used in order to separate polyphenols from industrial residues of camu-camu. The effects of operational conditions of the cloud point extraction (CPE) on the polyphenol recovery and volumetric ratio were investigated. The results showed a maximum recovery of 95.71% that was obtained using 7.0 wt% Triton X-114, native pH (3.25), and 80 wt% polyphenol extract at 30 °C. The use of cloud point extraction was successful to recover the polyphenols from agroindustrial residue since it is a simple as well as of low-cost technique. 相似文献
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64.
Quantum states engineering: Recurrence formula including states with even and odd numbers of photons
Abstract A previous recurrence formula using the resonant atom-field interaction for the generation of a field state in a cavity is extended to arbitrary states having even and odd numbers of photons in their photon-number distribution. 相似文献
65.
Collagen-induced arthritis (CIA) is a T cell-dependent disease in which susceptibility is controlled by genes both within and outside the major histocompatibility complex (MHC). In the present study, we compared the humoral responses and kinetics of cytokine secretion patterns in the draining lymph nodes of arthritis-susceptible DA rats and arthritis-resistant F344 and DA MHC congenic PVG.1AV1 rats immunized with rat type II collagen (RCII) in incomplete Freund's adjuvant. The results demonstrate a marked humoral RCII response and a Th1 cytokine profile, with expression of interferon-gamma and interleukin (IL)-2 mRNA in DA rats; a limited humoral RCII response and a Th2 cytokine profile, with expression of IL-4 mRNA in arthritis-resistant F344 rats; and a marked humoral RCII response in arthritis-resistant PVG.1AV1 rats. However, in contrast to DA rats, PVG.1AV1 rats produce IgG1 autoantibodies which, together with strong expression of IL-4 mRNA, indicates the involvement of Th2 subsets. From these data, we conclude that non-MHC gene(s) determines the direction of the anti-RCII response towards a Th1 disease-promoting, or a Th2 disease-limiting response. 相似文献
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67.
GJ Juvenal LB Pregliasco L Krawiec LV Bocanera D Silberschmidt MA Pisarev 《Canadian Metallurgical Quarterly》1997,7(5):795-800
The sympathetic nervous system plays a role in the regulation of thyroid function. In FRTL-5 rat thyroid cells, norepinephrine (NE) acutely depresses intracellular I- by increasing I- efflux. The present study was undertaken to determine the effect of NE on iodide transport after a longer time period. NE inhibited the ability of thyrotropin (TSH) to induce iodide uptake by FRTL-5 cells after 48 or 72 hours, but not after 24 hours. The effect of NE was more evident with increasing concentrations of TSH. NE did not modify the rate of I- efflux. Inhibition was associated with a decrease in the Vmax and no change in the Km for iodide influx. To determine if this was a generalized effect of NE on thyroid cell membrane, the uptake of alpha-aminoisobutyric acid (a nonmetabolizable aminoacid) and of 2-deoxyglucose was measured. NE did not inhibit TSH stimulation of the uptake of the two compounds. NE inhibited the action of dibutyryl cAMP (dbcAMP) on iodide uptake in a similar manner to TSH, but did not alter the cyclic adenosine monophosphate (cAMP) levels increased by TSH. The effects of different adrenoreceptor agonists and antagonists demonstrated that norepinephrine acts through an alpha1-adrenergic receptor. 相似文献
68.
LA Smith DE Barker CW Chase LB Somberg WB Brock RP Burns 《Canadian Metallurgical Quarterly》1997,63(12):1102-7; discussion 1107-8
The purpose of this review is to present a 4-year experience with the vacuum pack technique of temporary abdominal closure. From April 1992 to December 1996, 171 vacuum packs were performed on 93 patients. Eighty-seven vacuum packs were performed on 38 general surgical patients, and 84 vacuum packs were performed on 55 trauma patients. Overall hospital mortality was 32 per cent. Methods of achieving permanent wound closure varied in 73 patients. Four patients (4.3%) developed enterocutaneous fistulae; four patients developed intra-abdominal abscesses (4.3%). There were no eviscerations. Management of the complicated intra-abdominal process is discussed: 1) the decision to manage the abdomen in an open fashion; 2) which method of temporary closure to use; 3) subsequent explorations; 4) when the abdomen should be closed; 5) which type of closure to use; and 6) when the abdominal wall should be revised (herniorrhaphy). The vacuum pack is the method of choice for open abdomen management and temporary abdominal closure at our institution. With careful subsequent management, good patient outcome can be achieved. 相似文献
69.
VG Savchenko EN Parovichnikova VG Isaev IA Demidova RG Kuliev EO Gribanova GA Kliasova RA Kucher AN Sokolov KS Momotiuk IuV Ol''shanskaia NG Tiurina LIu Tikhonova GM Galstian VM Budianski? EA Belousov VA Lapin SV Voloshin TS Konstaninova LB Filatov ON Porokhina EA Smirnova 《Canadian Metallurgical Quarterly》1998,70(7):5-11
70.
A Hornsleth B Klug M Nir J Johansen KS Hansen LS Christensen LB Larsen 《Canadian Metallurgical Quarterly》1998,17(12):1114-1121
BACKGROUND: Investigations concerning the severity of respiratory syncytial virus (RSV) disease as related to (1) RSV type and genotype determined respectively by PCR and restriction enzyme analysis and (2) interleukin 6 (IL-6) and tumor necrosis factor alpha (TNF-alpha) values in samples of nasopharyngeal secretion (NPS) have not been previously reported. METHODS: We prospectively studied 105 RSV infections in the lower respiratory tract of infants and young children admitted to a pediatric department in Copenhagen during three winter seasons, 1993, 1994 and 1995. RSV strains were typed and genotyped, respectively, by PCR and nucleic acid restriction analysis and correlated to the severity of the disease. The ratio IL-6:TNF-alpha, determined from IL-6- and TNF-alpha values in samples of NPS, was related to the severity of the disease. Concentrations of IL-6 and of TNF-alpha were determined in serum samples taken during 5 weeks after the onset of illness. RESULTS: Type B infections produced more severe disease than did type A infections, as assessed on the length of the hospital stay, use of respiratory support and the presence of an infiltrate on a chest radiograph. This difference was age-related. It was observed in infants 0 to 5 months old, but not in older age groups. Type B genotype B1122 produced more severe disease than type A genotype A2311 in infants 0 to 11 months old. Increased serum concentrations of IL-6 and TNF-alpha were detected in samples taken 1 to 2 days after the onset of illness. Whereas TNF-alpha serum concentrations remained high, IL-6 serum concentrations decreased during the following 3 to 4 weeks. The IL-6:TNF-alpha ratio in samples of NPS was related to the severity of the disease. A high ratio was related to a low severity. CONCLUSIONS: The severity of disease in patients admitted with acute RSV infections can be correlated to the RSV type as determined by PCR, to the RSV genotype as determined by nucleic acid restriction analysis and to the ratio IL-6:TNF-alpha in NPS. 相似文献