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31.
Three phase partitioning for extraction of oil from soybean 总被引:4,自引:0,他引:4
Three phase partitioning, a method generally used for protein separation, has been evaluated for extraction of oil from soybean. 82% oil was extracted within 1 h using this process which required simultaneous addition of t-butanol (1:1, v/v) and 30% ammonium sulphate to the soybean slurry. 相似文献
32.
33.
Reddacliff LA Nicholls PJ Vadali A Whittington RJ 《Applied and environmental microbiology》2003,69(6):3510-3516
A simple method for using growth indices from radiometric BACTEC cultures was evaluated for the enumeration of Australian sheep strains of Mycobacterium avium subsp. paratuberculosis. The numbers of viable organisms in inocula were determined by end-point titration in BACTEC cultures. Growth indices were measured by using a BACTEC 460 machine. There was a linear relationship between the number of days taken for the cumulative growth index to reach 1,000 (dCGI1000) and log(10) inoculum size. The use of dCGI1000 was shown to be as effective as the use of growth index data from the entire growth cycle for the estimation of inoculum size. For particular isolates characterized by end-point titration, the dCGI1000 of a single BACTEC vial provided estimates of viable numbers within narrow prediction limits. Predictive relationships were also established for the enumeration of M. avium subsp. paratuberculosis from field samples by using the dCGI1000 of a single BACTEC vial, with prediction limits of +/-1 to 2 log units. Organisms from feces or contaminated soil grew more slowly than those from cultures or tissues, and separate equations were developed for enumeration from these sources. 相似文献
34.
We have synthesized N-(2-hydroxypropyl)methacrylamide (HPMA) copolymer-cell penetrating peptide Tat conjugates and evaluated their subcellular distribution in A2780 human ovarian carcinoma cells by confocal fluorescence microscopy and subcellular fractionation. Our data indicate the transport of these conjugates by a single Tat molecule to both the cytoplasm and nucleus via a nonendocytotic and concentration independent process. The uptake was observed to occur within 3 min, as confirmed by live cell microscopy. In contrast, HPMA copolymers lacking the Tat peptide were internalized solely by endocytosis. For the first time, Tat-mediated cytoplasmic delivery of a polymer bound anticancer drug, doxorubicin, was also demonstrated. These findings establish the feasibility of overcoming major cellular and subcellular obstacles to intracellular macromolecular delivery and hold great promise for the development of polymer-based systems for the cytoplasmic delivery of therapeutic molecules. 相似文献
35.
Venkatraman A Ramakrishna BS Shaji RV Kumar NS Pulimood A Patra S 《American journal of physiology. Gastrointestinal and liver physiology》2003,285(1):G177-G184
Butyrate enemas have been demonstrated to ameliorate inflammation in ulcerative colitis. The mechanism of this protective effect of butyrate is not known, and this study examines the effect of butyrate on epithelial function, inducible heat shock protein 70 (HSP70) expression, and NF-kappaB activation in experimental colitis. Colitis was induced in rats by oral dextran sulfate sodium (DSS) and by butyrate or saline enemas. Mucosal barrier function was assessed by electrical resistance and [14C]mannitol permeability. HSP70 production was determined by [35S]methionine labeling, Western blot analysis, and immunohistochemistry. Activation of heat shock factors (HSFs) and NF-kappaB was evaluated by EMSA. Butyrate showed a significant protection against the decrease in cell viability, increase in mucosal permeability, and polymorphonuclear neutrophil infiltration seen in DSS colitis. Butyrate inhibited HSP70 expression in DSS colitis and also inhibited the activation of HSF and NF-kappaB. Thus butyrate enema was found to be cytoprotective in DSS colitis, an effect partly mediated by suppressing activation of HSP70 and NF-kappaB. 相似文献
36.
The purpose of this study was to determine whether human galanin, a pleiotropic 30-amino acid neuropeptide, expresses amphipathic properties in vitro and, if so, whether these properties modulate its vasoactive effects in the intact peripheral microcirculation. We found that human galanin aggregates in an aqueous solution and forms micelles with a critical micellar concentration (CMC) of 0.4 microM. In addition, the peptide interacted with model membrane as indicated by long and significant increase of the surface pressure of the biomimetic monolayer membrane in vitro. Interactions of human galanin with sterically stabilized phospholipid micelles (SMM) were not associated with a significant change in peptide conformation. Using intravital microscopy, we found that suffusion of human galanin alone elicited significant concentration-dependent vasoconstriction in the intact hamster cheek pouch. This response was amplified when human galanin in SSM was suffused onto the cheek pouch. The effects of human galanin alone and in SSM were mediated by galanin receptors because galantide, a galanin receptor antagonist, abrogated galanin-induced vasoconstriction. Collectively, these data show that human galanin expresses amphipathic properties in the presence of phospholipids which in turn amplifies its vasoactive effects in the intact peripheral microcirculation. 相似文献
37.
A simple titrimetric assay with soybean lecithin has been used for screening phospholipase D activity from some plant sources, viz. peanut, wheat germ, cabbage and carrot. The enzyme from peanut has been purified by binding to alginate which is a water soluble polymer. The purification consisted of co-precipitation of enzyme with alginate upon addition of 0.06 M Ca++. The enzyme was eluted from the polymer using 0.2 M sodium chloride. The activity recovery was 61% with 34 fold purification. 相似文献
38.
Karthik Sivaraman Aditi Chopra Aparna Narayana Raghu A. Radhakrishnan 《Gerodontology》2021,38(1):17-26
Severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) is an RNA virus that causes coronavirus infection (COVID‐19). COVID‐19 is a highly contagious disease transmitted through respiratory droplets, saliva and other contact routes. Within 10 months of its outbreak, SARS‐CoV‐2 has infected more than 23 million people around the world. Evidence suggests that older adults are the most vulnerable to infection and have an increased risk of mortality. Reduced immunity and underlying medical conditions make them risk‐prone and vulnerable to critical care. Older adults affected with the SARS‐CoV‐2 virus present with distinct clinical manifestations necessitating specific treatment needs and management protocols. While it is crucial to prevent the spread of novel coronavirus (2019‐nCoV), the role of oral healthcare workers in addressing the specific needs of ageing adult patients by adopting specific guidelines and appropriate infection control protocols is timely. This paper aims to develop specific guidelines and protocols for the dental management of geriatric patients during the COVID‐19 pandemic. 相似文献
39.
Daniel Martinez-Ramirez Juan Giugni Vinata Vedam-Mai Aparna Wagle Shukla Irene A. Malaty Nikolaus R. McFarland Ramon L. Rodriguez Kelly D. Foote Michael S. Okun 《PloS one》2014,9(4)
Objective
Formulate a definition and describe the clinical characteristics of PD patients with a “brittle response” (BR) to medications versus a “non-brittle response” (NBR), and characterize the use of DBS for this population.Methods
An UF IRB approved protocol used a retrospective chart review of 400 consecutive PD patients presenting to the UF Center for Movement Disorders and Neurorestoration. Patient records were anonymized and de-identified prior to analysis. SPSS statistics were used to analyze data.Results
Of 345 included patients, 19 (5.5%) met criteria for BR PD. The BR group was comprised of 58% females, compared to 29% in the NBR group (P = .008). The former had a mean age of 63.4 compared to 68.1 in the latter. BR patients had lower mean weight (63.5 vs. 79.6, P = <.001), longer mean disease duration (12.6 vs. 8.9 years, P = .003), and had been on LD for more years compared to NBR patients (9.8 vs. 5.9, P = .001). UPDRS motor scores were higher (40.4 vs. 30.0, P = .001) in BR patients. No differences were observed regarding the Schwab and England scale, PDQ-39, and BDI-II. Sixty-three percent of the BR group had undergone DBS surgery compared to 18% (P = .001). Dyskinesias were more common, severe, and more often painful (P = <.001) in the BR group. There was an overall positive benefit from DBS.Conclusion
BR PD occurred more commonly in female patients with a low body weight. Patients with longer disease duration and longer duration of LD therapy were also at risk. The BR group responded well to DBS. 相似文献40.
Malcolm R. Macleod Aaron Lawson McLean Aikaterini Kyriakopoulou Stylianos Serghiou Arno de Wilde Nicki Sherratt Theo Hirst Rachel Hemblade Zsanett Bahor Cristina Nunes-Fonseca Aparna Potluru Andrew Thomson Julija Baginskitae Kieren Egan Hanna Vesterinen Gillian L. Currie Leonid Churilov David W. Howells Emily S. Sena 《PLoS biology》2015,13(10)