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71.
Nowadays, safety and quality assessment of food used for human consumption have to consider by its possible contribution to the
maintenance or improvement of the consumer''s health. Milk is an important food with many nutrients. Cow milk is an important
source of energy, protein, vitamins and minerals for the growing child as well as adults. But, numerous cow milk proteins have
been implicated in allergic responses and most of these have been shown to contain multiple allergic epitopes. The present study
disclosed best alternatives to cow milk, which are not allergic and as good as cow milk in nutritional value. The in silico analysis of
casein (alpha s1, alpha s2, beta and kappa) and beta-lactoglobulin, unveils that sheep milk is a more suitable alternate to cow milk
for allergic infants and buffalo milk for allergic adult humans. 相似文献
72.
73.
74.
Female mate preference based on male orange spot patterns in the feral guppy <Emphasis Type="Italic">Poecilia reticulata</Emphasis> in Japan 总被引:2,自引:2,他引:0
Kenji?Karinokkarino@u-gakugei.ac.jp" title="KK kkarino@u-gakugei.ac.jp" itemprop="email" data-track="click" data-track-action="Email author" data-track-label="">Email author Shinya?Shinjo 《Ichthyological Research》2004,51(4):316-320
It is known that females prefer males with larger and/or brighter orange spots in many populations of the guppy Poecilia reticulata. However, female preference for male orange spots varies among populations and changes within several years when they are introduced into new habitats with different environment. Guppies were introduced into Okinawa, Japan, more than 20 years ago and were subjected to natural and sexual selection for a long period. The female preference for orange spot patterns of males was examined by the dichotomous choice experiment for a feral guppy population of the Hiji River, Okinawa. We chose full-sibling males as a pair of stimulus males that were simultaneously presented to a test female, because sibling males should resemble each other. To create different orange spot patterns between stimulus males, one male of the stimulus male pair was fed carotenoid-supplement food such as algae and another male was fed low-carotenoid food. High-carotenoid-treatment males showed not only brighter coloration of orange spots but also larger spots than other males as a result of this dietary-manipulation. In the dichotomous choice experiment, females preferred the high-carotenoid-treatment males. In addition, logistic regression analysis clarified that brighter coloration of male orange spots was the most important factor for female mate preference. This finding suggests indirect benefits of female preference for male orange spot patterns if the male foraging ability for algae were heritable. 相似文献
75.
In this study three different flow cytometric analysis techniques are woven together into a single system that permits improved detection of small percentages of monoclonal B cells in a milieu of either normal blood leukocytes or bone marrow cells. This analysis is an extension of the concept of clonal excess, which is used to detect the presence of a tumor that is a clonal expansion of B cells expressing either kappa or lambda light chains. The technique also utilizes "multiple listmode processing," which is defined in this context as the simultaneous analysis of two or more listmode files that share one or more common parameters. This type of data structure enables the segmentation of two parameter light scatter displays into regions from which numerous kappa and lambda histograms subsequently can be analyzed for their respective Komogorov-Smirnov D-values or R-values (reduced chi-square value). The final technique makes use of a calculated parameter display system. Superimposed on the light scatter dot density plot are D-value or R-value contours. The contours target the location of the population that is abnormal, thus providing information for setting optimal bitmap gates for clonal excess studies, other phenotypic analyses, or cell sorting. In experiments using model systems, the sensitivity of this assay is estimated to be between 0.25% and 2.5%. The technique's distribution information and sensitivity may prove useful for staging, treatment monitoring, and relapse detection of B-cell leukemia and lymphoma. This application illustrates the potential of combining multiple listmode processing and calculated parameter display to expand the effective dimensionality of listmode data. 相似文献
76.
Meiosis in Drosophila melanogaster. V. Univalent behavior in In(1)sc4Lsc8R/BsY males 总被引:1,自引:0,他引:1
Univalent behavior during meiosis has been examined in Drosophila melanogaster males possessing the In(1)sc4Lsc8R X chromosome using light microscopy and serial section electron microscopy. Males from two stocks, displaying high (0.40) and low (0.14) frequencies of sex chromosome nondisjunction, have been investigated. The results demonstrate that (i) sex chromosomes are more intimately paired during prometaphase I in males from the low nondisjunction stock than in males from the high nondisjunction stock, and (ii) the univalents are distributed to the poles in an unbiased manner during meiosis rather than by directed segregation of both univalents to the same pole as previously determined for other In(1)sc4Lsc8R/Y males. 相似文献
77.
Astringency of aqueous solutions of phenolic compounds (grape seed tannins,
tannic acid, catechin and gallic acid) increased upon addition of citric
acid, whereas the astringency of alum was reduced. Astringency of alum was
decreased equivalently by addition of equi-sour levels of lactic acid,
citric acid or hydrochloric acid. The difference between alum and the
phenolic compounds is speculated to result from chemical modifications
affecting binding of the astringents with oral proteins rather than
cognitive differences. Chelation of the aluminum ion in alum by acids
reduces its availability for interacting with salivary proteins or
epithelial proteins. In contrast, the increased astringency produced upon
acidification of phenolic compounds is speculated to result from the pH
driven increase in the affinity of the phenols for binding with proteins.
These results suggest that alum cannot be used interchangeably with
phenolic astringents in psychophysical studies.
相似文献
78.
In culture, human blood B cells regenerated surface IgM and IgD after their removal by a brief treatment with pronase. In contrast, surface Ig was poorly reexpressed after interaction with specific antibody. Both classes of surface Ig were suppressed after treatment with antibody specific for only one. B lymphocytes from spleen and tonsils regenerated surface Ig after treatment with either pronase or anti-Ig. We suggest that the particular sensitivity of circulating B cells to anti-Ig-surface Ig interaction may be reflection of their state of maturation. 相似文献
79.
Natural killer cell activity in multiple sclerosis 总被引:3,自引:0,他引:3
S L Hauser K A Ault M J Levin M R Garovoy H L Weiner 《Journal of immunology (Baltimore, Md. : 1950)》1981,127(3):1114-1117
80.
Increased mitochondrial cytochrome c levels and mitochondrial hyperpolarization precede camptothecin-induced apoptosis in Jurkat cells 总被引:4,自引:0,他引:4
Sánchez-Alcázar JA Ault JG Khodjakov A Schneider E 《Cell death and differentiation》2000,7(11):1090-1100
Mitochondria play a central role in apoptosis through release of cytochrome c and activation of caspases. In the present study, we showed that, in Jurkat human T cells, camptothecin-induced apoptosis is preceded by (i) an increase in cytochrome c and subunit IV of cytochrome c oxidase (COX IV) levels in mitochondria; and (ii) an elevation of the mitochondrial membrane potential (Delta(Psi)m). These events are followed by cytochrome c release into the cytosol, cytochrome c and COX IV depletion from mitochondria, externalization of phosphatidylserine (PS), disruption of Delta(Psi)m, caspase activation, poly(ADP-ribose)polymerase cleavage and DNA fragmentation. The pan-caspase inhibitor z-VAD.fmk blocked camptothecin-induced PS externalization, disruption of Delta(Psi)m and DNA fragmentation, suggesting that these events are mediated by caspase activation. In contrast, z-VAD did not prevent cytochrome c release, despite preventing cytochrome c and COX IV depletion from mitochondria. Together, these data suggest that mitochondrial cytochrome c and COX IV enrichment are early events preceding the onset of apoptosis and that cytochrome c release is upstream of caspase activation and loss of Delta(Psi)m. Furthermore, prevention by z-VAD of cytochrome c and COX IV depletion in mitochondria suggests the possibility that a caspase-like activity in mitochondria is involved in the proteolytic depletion of respiratory chain proteins. Activation of this activity may play an important role in drug-induced apoptosis. 相似文献