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81.
Bach ML  Bach FH  Joo P 《Science (New York, N.Y.)》1969,166(3912):1520-1522
Patients with acute leukemia (blast cells in the peripheral blood) manifest antigens in the one-way mixed leukocyte culture test. Leukocytes from normal patients and leukocytes of patients in remission do not clearly show these antigens. These antigens could be leukemia-associated antigens in man.  相似文献   
82.
Abstract

The milk composition in a Swedish herd, consisting of Swedish Red and White cows (SRB) and Swedish Holstein cows (SLB), and in a Danish herd, consisting of Danish Holstein-Friesian cows (SDM), was evaluated. Concentrations of the major milk proteins (κ-casein, αS1-casein, β-casein, β-lactoglobulin A, β-lactoglobulin B and α-lactalbumin) of 134 individual milk samples were determined by reversed phase (RP) HPLC. Other parameters determined included milk fat, urea, lactose, calcium, lactoferrin, somatic cell count and protein degradation (determined as level of free amino-terminals). Analysis of variance was used to compare concentrations of analysed milk variables between SRB and SLB or between SLB and SDM. Concentration of total protein, total casein, β-casein and κ-casein were significantly higher in SRB milk compared with SLB milk. Concentration of α-lactalbumin and calcium were significantly higher in SDM milk than in SLB milk. The concentration of urea was higher in SLB than in SDM milk and is suggested to reflect differences in feeding regimes between the investigated Swedish and Danish herd.  相似文献   
83.
The characterization of the full complement of wheat ferritins show that the modern hexaploid wheat genome contains two ferritin genes, TaFer1 and TaFer2, each represented by three homeoalleles and placed on chromosome 5 and 4, respectively. The two genes are differentially regulated and expressed. The TaFer1 genes are, except in the endosperm, the most abundantly expressed and regulated by iron and abscisic acid status. The promoter of TaFer1, in contrast to TaFer2, has iron- and ABA-responsive elements, supporting the expression data. The TaFer1 and TaFer2 genes encode two isoforms, probably functional different and acting in heteropolymer structures of ferritin in cereals. Iron biofortification of the wheat grain is possible. Endosperm targeted intragenic overexpressing of the TaFer1-A gene results in a 50–85% higher iron content in the grain.  相似文献   
84.
Hypoxia inducible factor-1α (HIF-1α) is an essential regulator of the cellular response to low oxygen concentrations, activating a broad range of genes that provide adaptive responses to oxygen deprivation. HIF-1α is overexpressed in various cancers and therefore represents a considerable chemotherapeutic target. Salternamide A (SA), a novel small molecule that is isolated from a halophilic Streptomyces sp., is a potent cytotoxic agent against a variety of human cancer cell lines. However, the mechanisms by which SA inhibits tumor growth remain to be elucidated. In the present study, we demonstrate that SA efficiently inhibits the hypoxia-induced accumulation of HIF-1α in a time- and concentration-dependent manner in various human cancer cells. In addition, SA suppresses the upstream signaling of HIF-1α, such as PI3K/Akt/mTOR, p42/p44 MAPK, and STAT3 signaling under hypoxic conditions. Furthermore, we found that SA induces cell death by stimulating G2/M cell cycle arrest and apoptosis in human colorectal cancer cells. Taken together, SA was identified as a novel small molecule HIF-1α inhibitor from marine natural products and is potentially a leading candidate in the development of anticancer agents.  相似文献   
85.
For several mammalian species, it has been shown that fetal and early postnatal nutrition has a role in long-term lipid and glucose metabolism of the offspring, and it thus also may have consequences on milk yield in the dairy cow. For instance, high-energy diets during the last weeks of pregnancy may result in increased glycemia, which in turn, may alter fetal adipose tissue development. However, most research efforts on management and nutrition of dry cows have focused on minimizing metabolic disorders of the postpartum cow without devoting much attention to potential consequences for the offspring. Similarly, nutritional needs for proper placental development and early fetal growth have received little attention, despite the fact that alterations in placental and fetal development may alter expression of genes participating in homeorhesis of the offspring. Therefore, nutrition of the pregnant cow, both while lactating and dry, should also consider aspects of placental and fetal development that may affect health and performance of the progeny. Similarly, newborn calves and young heifers are fed to ensure a particular growth target without compromising mammary development, although data linking postnatal growth targets with future milk yield are scarce. However, milk yield not only depends on mammary development, but also on nutrient partitioning, which is regulated by the endocrine milieu. There are some periods of time during development where nutrition may have long-lasting effects on metabolic function and milk production. For instance, the first months of postnatal life seem to be critical because recent data from both retrospective and controlled studies indicate that increased growth rate or plane of nutrition during this phase is positively associated with future milk production. Postnatal growth rate depends on nutrition (a necessary but not sufficient condition) and management (i.e., grouping strategies and housing systems), and thus optimal rearing programs should be designed considering long-term consequences on milk yield.  相似文献   
86.
Thirty-two crossbred lambs (BW = 31.2 ± 4.7 kg; 16 females, 16 males) housed in individual pens were used to investigate the relationship between nutrient supply and taste preferences in ruminants. Experiment 1 determined whether an imbalanced CP supply would alter preferences for feeds containing flavors designed to elicit either umami (U) or a mixture (1/3:1/3:1/3) of umami, sweet, and bitter (M) tastes. Lambs were randomly allocated to either a low (LP; 10.9% CP) or a high (HP; 20.4% CP) CP diet for 21 d. Afterward, lambs were presented during 21 d with a choice of the same LP or HP diet unflavored (LPC or HPC, respectively) or flavored (0.1% as fed) with U (LPU or HPU, respectively) or M (LPM or HPM). Experiment 2 determined the influence of CP status on preference for dietary CP, bitter taste, and sweet taste elicited by sucrose or a noncaloric sweetener. In test 1, sixteen lambs previously fed LP or HP for 42 d in Exp. 1 could choose between the HP and LP diets. In test 2, the remaining 16 lambs from Exp. 1 were offered a choice between unflavored LP or HP diets or the same diets flavored (0.066% as fed) with a bitter flavor. In test 3, the 16 lambs from test 1 were offered a choice between an unflavored diet (LP or HP) and the same diet flavored with sucrose (0.2%) or a noncaloric sweetener (0.066%). In Exp. 1, when offered a choice, all lambs showed a preference (P < 0.05) for the unflavored diet except for LP lambs, who clearly preferred (P < 0.05) LPU (72% of total DMI) over LPC. However, preference for LPU progressively decreased (P < 0.05) as time of exposure to the choice increased. In Exp. 2 (test 1), lambs previously fed LP progressively increased (P < 0.05) total DMI when presented with LP and HP, whereas consumption was constant for lambs previously fed HP and offered a choice of LP and HP diets. At the onset of test 2, lambs fed LP progressively reduced (P < 0.05) preference for the bitter flavor from 53 to 34%. In test 3, lambs previously fed LP diets consumed less (P < 0.05) sweetener- than sucrose-supplemented diet, whereas lambs previously offered HP diets consumed more sweetener- than sucrose-supplemented diet. In summary, protein-restricted lambs were able to differentiate and increase consumption of U-flavored feeds. However, this increase disappeared over time. These results indicate that lambs are able to sense dietary CP content and modulate short-term consumption of flavored feeds based on their nutrient requirements.  相似文献   
87.
The blue shark (Prionace glauca) is the most frequently captured shark in pelagic oceanic fisheries, especially pelagic longlines targeting swordfish and/or tunas. As part of cooperative scientific efforts for fisheries and biological data collection, information from fishery observers, scientific projects and surveys, and from recreational fisheries from several nations in the Atlantic and Indian Oceans was compiled. Data sets included information on location, size and sex, in a total of 478,220 blue shark records collected between 1966 and 2014. Sizes ranged from 36 to 394 cm fork length. Considerable variability was observed in the size distribution by region and season in both oceans. Larger blue sharks tend to occur in equatorial and tropical regions, and smaller specimens in higher latitudes in temperate waters. Differences in sex ratios were also detected spatially and seasonally. Nursery areas in the Atlantic seem to occur in the temperate south‐east off South Africa and Namibia, in the south‐west off southern Brazil and Uruguay, and in the north‐east off the Iberian Peninsula and the Azores. Parturition may occur in the tropical north‐east off West Africa. In the Indian Ocean, nursery areas also seem to occur in temperate waters, especially in the south‐west Indian Ocean off South Africa, and in the south‐east off south‐western Australia. The distributional patterns presented in this study provide a better understanding of how blue sharks segregate by size and sex, spatially and temporally, and improve the scientific advice to help adopt more informed and efficient management and conservation measures for this cosmopolitan species.  相似文献   
88.
Fenhexamid, a recently developed botryticide, is shown here to inhibit sterol biosynthesis. When the fungus Botryotinia fuckeliana was grown in the presence of fenhexamid, the ergosterol content was reduced, and three 3‐keto compounds, 4α‐methylfecosterone, fecosterone and episterone, accumulated, suggesting an inhibition of the 3‐keto reductase involved in C‐4 demethylation. Thus, fenhexamid belongs to a new, promising class of sterol biosynthesis inhibitors not previously used in agriculture or in medicine. © 2001 Society of Chemical Industry  相似文献   
89.
Junctional epidermolysis bullosa (JEB) is a mechanobullous skin disease associated with mutations in the basement membrane components of the dermo-epidermal junction. This condition is a suitable prototype for proving the feasibility of a gene therapy approach to genodermatoses. As successful genetic treatment requires immunocompetent animal models to study the possible host immune response to the transgene, we have characterized a breed of short-haired pointers suffering from a mild form of JEB. These animals exhibit skin blistering and erosions following minor trauma. Immunohistochemical analysis of the skin biopsies and immunoprecipitation of spent medium from cultured JEB keratinocytes showed reduced expression and secretion of the α3 chain of laminin 5 (α3, β3, γ2), the major adhesion ligand of basal keratinocytes. The search for genetic mutations detected a homozygous insertional mutation (4818 + 207 ins6.5 kb) in intron 35 of the lama3 gene. Consequently, keratinocytes from dogs with JEB secrete reduced amounts of wild-type laminin 5, and adhesive properties of the keratinocytes are compromised. Retroviral transfer of wild-type dog α3 cDNA into JEB keratinocytes enhanced secretion of laminin 5 in the extracellular matrix and restored the adhesion, differentiation and proliferative capacity of the transduced cells. Transplantable fibrin-based skin equivalents made with transduced JEB keratinocytes and grafted onto SCID mice generated normal cohesive and stratified epithelia and showed stable localized deposition of laminin 5 at the dermo-epidermal junction. Our results form the basis for preclinical assays of gene therapy on a unique immunocompetent animal model for an inherited skin disease.
Funding: DEBRA (UK) Foundation, Association Francaise Contre les Myopathies.  相似文献   
90.
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