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1.
Theoretical calculation of the sugar concentrations during enzymatic production of fructooligosaccharides 总被引:1,自引:0,他引:1
Summary In a batch production of fructooligosaccharides from sucrose, the concentrations of residual sucrose, glucose and fructooligosaccharides at a given reaction time(t) and initial sucrose concentration(S0) were theoretically calculated by the following correlation equations: Glucose(t) = 0.0653 S0 × ln(t); Fructooligosaccharides(t) = 0.1636 S0 × ln(t); Sucrose(t)=S0 - Glucose(t) + FOS(t). 相似文献
2.
Blood samples are commonly obtained in many experimental contexts to measure targets of interest, including hormones, immune factors, growth factors, proteins, and glucose, yet the composition of the blood is dynamically regulated and easily perturbed. One factor that can change the blood composition is the stress response triggered by the sampling procedure, which can contribute to variability in the measures of interest. Here we describe a procedure for blood sampling from the lateral tail vein in the rat. This procedure offers significant advantages over other more commonly used techniques. It permits rapid sampling with minimal pain or invasiveness, without anesthesia or analgesia. Additionally, it can be used to obtain large volume samples (upwards of 1 ml in some rats), and it may be used repeatedly across experimental days. By minimizing the stress response and pain resulting from blood sampling, measures can more accurately reflect the true basal state of the animal, with minimal influence from the sampling procedure itself. 相似文献
3.
William J. Sames Terry A. Klein Heung Chul Kim Sung Tae Chong In Yong Lee Se Hun Gu Yon Mi Park Ji Hye Jeong Jin‐Won Song 《Journal of vector ecology》2009,34(2):225-231
The Twin Bridges Training Area (TBTA) in the Republic of Korea consists of dirt roads, barren training areas, and forested hillsides adjacent to linear and broad expanses of tall grasses, herbaceous, and scrub vegetation. Of the six species of small mammals, the striped field mouse, Apodemus agrarius, was the most frequently captured (96.1%). Apodemus agrarius capture rates varied from 17.7 to 33.2% during three trapping periods. Gravid females were observed during November‐December 2006 (8.4%) and March 2007 (5.1%). In 2005, the overall seroprevalence of Hantaan virus (HTNV) was high (34.4%) and lower during surveys in 2006 (14.2%) and 2007 (13.8%). Seroprevalence was directly correlated with weight increase of A. agrarius. 相似文献
4.
5.
Nucleotide sequence of the gene encoding the Corynebacterium glutamicum mannose enzyme II and analyses of the deduced protein sequence 总被引:2,自引:0,他引:2
Jung-Kee Lee Moon-Hee Sung Ki-Hong Yoon Ju-Hyun Yu Tae-Kwang Oh 《FEMS microbiology letters》1994,119(1-2):137-145
Abstract The complete nucleotide sequence of the gene encoding the Corynebacterium glutamicum mannose enzyme II (EIIMan ) was determined. The gene consisted of 2052 base pairs encoding a protein of 683 amino acid residues; the molecular mass of the protein subunit was calculated to be 72570 Da. The N-terminal hydrophilic domain of EIIMan showed 39.7% homology with a C-terminal hydrophilic domain of Escherichia coli glucose-specific enzyme II (EIIGlc ). Similar homology was shown between the C-terminal sequence of EIIMan and the E. coli glucose-specific enzyme III (EIIIGlc ), or the EIII-like domain of Streptococcus mutans sucrose-specific enzyme II. Sequence comparison with other EIIs showed that EIIMan contained residues His-602 and Cys-28 which were homologous to the potential phosphorylation sites of EIIIGlc , or EIII-like domains, and hydrophilic domains (IIB) of several EIIs, respectively. 相似文献
6.
Seunghun Lee Won Yeong Park Hoonchul Chang Bumju Kim Won Hyuk Jang Seonghan Kim Younghoon Shin Myoung Joon Kim Kyung Hwa Lee Eui Hyun Kim Euiheon Chung Ki Hean Kim 《Journal of biophotonics》2020,13(1)
Delineation of brain tumor margins during surgery is critical to maximize tumor removal while preserving normal brain tissue to obtain optimal clinical outcomes. Although various imaging methods have been developed, they have limitations to be used in clinical practice. We developed a high‐speed cellular imaging method by using clinically compatible moxifloxacin and confocal microscopy for sensitive brain tumor detection and delineation. Moxifloxacin is a Food and Drug Administration (FDA) approved antibiotic and was used as a cell labeling agent through topical administration. Its strong fluorescence at short visible excitation wavelengths allowed video‐rate cellular imaging. Moxifloxacin‐based confocal microscopy (MBCM) was characterized in normal mouse brain specimens and visualized their cytoarchitecture clearly. Then, MBCM was applied to both brain tumor murine models and two malignant human brain tumors of glioblastoma and metastatic cancer. MBCM detected tumors in all the specimens by visualizing dense and irregular cell distributions, and tumor margins were easily delineated based on the cytoarchitecture. An image analysis method was developed for automated detection and delineation. MBCM demonstrated sensitive delineation of brain tumors through cytoarchitecture visualization and would have potentials for human applications, such as a surgery‐guiding method for tumor removal. 相似文献
7.
Joohon Sung Kayoung Lee Yun‐Mi Song Mi Kyeong Lee Dong‐Hun Lee 《Obesity (Silver Spring, Md.)》2010,18(5):1000-1005
The heritability of eating behavior and body weight–related traits in Asian populations has not been reported. The purpose of this study was to estimate the heritability of eating behavior and the body weight–related traits of current weight and self‐reported past weight among twins and their families. Study subjects were 2,144 Korean, adult, same‐sex twins and their families at the ages between 20 and 65 years (443 monozygotic (MZ) and 124 dizygotic (DZ) twin pairs, and 1,010 individuals of their family). The Dutch Eating Behavior Questionnaire (DEBQ) was used to assess three eating behavior subscales measuring restraint, emotional eating, and external eating. A variance component approach was used to estimate heritability. After consideration of shared environmental effects and adjustment for age and sex effects, the heritability estimates ± s.e. among twins and their family members were 0.31 ± 0.036 for restraint, 0.25 ± 0.098 for emotional eating, 0.25 ± 0.060 for external eating, 0.77 ± 0.032 for measured current body weight, and 0.70 ± 0.051 for self‐reported weight at 20 years old. The three DEBQ subscales were associated with all weight related traits after adjustment for age and sex. These results suggest eating behaviors and weight‐related traits have a genetic influence, and eating behaviors are associated with obesity indexes. Our findings from Korean twin family were similar to those reported in Western populations. 相似文献
8.
A Venet I Bourgault A M Aubertin M P Kiény J P Levy 《Journal of immunology (Baltimore, Md. : 1950)》1992,148(9):2899-2908
To identify the target proteins of CD8+ T lymphocytes we have explored the cytolytic immune responses of 12 rhesus macaques experimentally infected with the simian immunodeficiency virus (SIVmac). Target cells were autologous B cell lines presenting SIVmac proteins after infection with recombinant vaccinia viruses. The eight following proteins were studied: ENV, POL, GAG, NEF, VIF, REV, TAT, and VPX. Macaque PBMC stimulated with Con A and expanded in T cell growth factor-containing medium produced cell lines with cytolytic activity in the majority of infected animals (9/12). The structural proteins ENV, POL, and GAG were recognized by cell lines derived from nine, eight, and six macaques, respectively. The small regulatory proteins also represented efficient CTL targets, a specific activity being detected against NEF (8/12), REV (7/12), VPX (7/12), TAT (6/12), and VIF (5/12). Most cytotoxic responses (except those directed against ENV) were mediated by CD8 cells and were MHC class I restricted. Limiting dilution analysis allowed us to quantify the frequency of CTL precursors and confirmed the high immunogenicity of multiple SIV proteins. Three different patterns of response could be defined: six animals were able to recognize at least six of the eight tested target proteins, two of them reacting with all eight target proteins. The other three responder macaques reacted only against a few SIV proteins, whereas no cytotoxic activity was detected in the three remaining infected macaques and in the nine negative controls. The six animals responding against multiple proteins were still healthy 12 to 22 mo after infection with two of them presenting a decrease in circulating CD4 cells concurrently to the disappearance of the CTL response. Conversely, three nonresponder or low responder macaques developed an overt disease after 4 to 12 mo, and two other presented a very low level of CD4 cells, suggesting that the pattern of response may be of prognostic value. 相似文献
9.
10.
Sung O. Park Heather L. Wamsley Kyungmi Bae Zhongbo Hu Xiaomiao Li Se-woon Choe William B. Slayton S. Paul Oh Kay-Uwe Wagner Peter P. Sayeski 《PloS one》2013,8(3)
Germline deletion of Jak2 in mice results in embryonic lethality at E12.5 due to impaired hematopoiesis. However, the role that Jak2 might play in late gestation and postnatal life is unknown. To understand this, we utilized a conditional knockout approach that allowed for the deletion of Jak2 at various stages of prenatal and postnatal life. Specifically, Jak2 was deleted beginning at either mid/late gestation (E12.5), at postnatal day 4 (PN4), or at ∼2 months of age. Deletion of Jak2 beginning at E12.5 resulted in embryonic death characterized by a lack of hematopoiesis. Deletion beginning at PN4 was also lethal due to a lack of erythropoiesis. Deletion of Jak2 in young adults was characterized by blood cytopenias, abnormal erythrocyte morphology, decreased marrow hematopoietic potential, and splenic atrophy. However, death was observed in only 20% of the mutants. Further analysis of these mice suggested that the increased survivability was due to an incomplete deletion of Jak2 and subsequent re-population of Jak2 expressing cells, as conditional deletion in mice having one floxed Jak2 allele and one null allele resulted in a more severe phenotype and subsequent death of all animals. We found that the deletion of Jak2 in the young adults had a differential effect on hematopoietic lineages; specifically, conditional Jak2 deletion in young adults severely impaired erythropoiesis and thrombopoiesis, modestly affected granulopoiesis and monocytopoiesis, and had no effect on lymphopoiesis. Interestingly, while the hematopoietic organs of these mutant animals were severely affected by the deletion of Jak2, we found that the hearts, kidneys, lungs, and brains of these same mice were histologically normal. From this, we conclude that Jak2 plays an essential and non-redundant role in hematopoiesis during both prenatal and postnatal life and this has direct implications regarding the inhibition of Jak2 in humans. 相似文献