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排序方式: 共有491条查询结果,搜索用时 31 毫秒
21.
Facilitated long chain fatty acid uptake by adipocytes remains upregulated relative to BMI for more than a year after major bariatric surgical weight loss 下载免费PDF全文
Fengxia Ge José L. Walewski Mehyar Hefazi Torghabeh Harrison Lobdell IV Chunguang Hu Shengli Zhou Gregory Dakin Alfons Pomp Marc Bessler Beth Schrope Aku Ude‐Welcome William B. Inabnet Tianshu Feng Elektra Carras‐Terzian Dieunine Anglade Faith E. Ebel Paul D. Berk 《Obesity (Silver Spring, Md.)》2016,24(1):113-122
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23.
K Königsson K Törneke IV Engeland K Odensvik H Kindahl 《Acta veterinaria Scandinavica》2003,44(4):153
The pharmacokinetics and the prostaglandin (PG) synthesis inhibiting effect of flunixin were determined in 6 Norwegian dairy
goats. The dose was 2.2 mg/kg body weight administered by intravenous (i.v.), intramuscular (i.m.) and oral (p.o.) routes
using a cross-over design. Plasma flunixin content was analysed by use of liquid chromatography and the PG synthesis was evaluated
by measuring plasma 15-ketodihydro-PGF2α by a radioimmuno-assay. Results are presented as median (range). The elimination half-lives (t1/2·λ) were 3.6 (2.0–5.0), 3.4 (2.6–6.8) and 4.3 (3.4–6.1) h for i.v., i.m. and p.o. administration, respectively. Volume of distribution
at steady state (Vdss) was 0.35 (0.23–0.41) L/kg and clearance (CL), 110 (60–160) mL/h/kg. The plasma concentrations after oral administration
showed a double-peak phenomenon with the two peaks occurring at 0.37 (0.25–1) and 3.5 (2.5–5.0) h, respectively. Both peaks
were in the same order of magnitude. Bioavailability was 79 (53–112) and 58 (35%–120)% for i.m. and p.o. administration, respectively.
15-Ketodihydro-PGF2α plasma concentrations decreased after flunixin administration independent of the route of administration. 相似文献
24.
Robert M. Immormino Louis E. Metzger IV D. Eric Dollins Brian S.J. Blagg 《Journal of molecular biology》2009,388(5):1033-238
Hsp90 chaperones contain an N-terminal ATP binding site that has been effectively targeted by competitive inhibitors. Despite the myriad of inhibitors, none to date have been designed to bind specifically to just one of the four mammalian Hsp90 paralogs, which are cytoplasmic Hsp90α and β, endoplasmic reticulum GRP94, and mitochondrial Trap-1. Given that each of the Hsp90 paralogs is responsible for chaperoning a distinct set of client proteins, specific targeting of one Hsp90 paralog may result in higher efficacy and therapeutic control. Specific inhibitors may also help elucidate the biochemical roles of each Hsp90 paralog. Here, we present side-by-side comparisons of the structures of yeast Hsp90 and mammalian GRP94, bound to the pan-Hsp90 inhibitors geldanamycin (Gdm) and radamide. These structures reveal paralog-specific differences in the Hsp90 and GRP94 conformations in response to Gdm binding. We also report significant variation in the pose and disparate binding affinities for the Gdm-radicicol chimera radamide when bound to the two paralogs, which may be exploited in the design of paralog-specific inhibitors. 相似文献
25.
Shaking a leg and hot to trot: the effects of body size and temperature on running speed in ants 总被引:1,自引:0,他引:1
Abstract. 1. Data were compiled from the literature and our own studies on 24 ant species to characterise the effects of body size and temperature on forager running speed.
2. Running speed increases with temperature in a manner consistent with the effects of temperature on metabolic rate and the kinetic properties of muscles.
3. The exponent of the body mass-running speed allometry ranged from 0.14 to 0.34 with a central tendency of approximately 0.25. This body mass scaling is consistent with both the model of elastic similarity, and a model combining dynamic similarity with available metabolic power.
4. Even after controlling for body size or temperature, a substantial amount of inter-specific variation in running speed remains. Species with certain lifestyles [e.g. nomadic group predators, species which forage at extreme (>60 °C) temperatures] may have been selected for faster running speeds.
5. Although ants have a similar scaling exponent to mammals for the running speed allometry, they run slower than predicted compared with a hypothetical mammal of similar size. This may in part reflect physiological differences between invertebrates and vertebrates. 相似文献
2. Running speed increases with temperature in a manner consistent with the effects of temperature on metabolic rate and the kinetic properties of muscles.
3. The exponent of the body mass-running speed allometry ranged from 0.14 to 0.34 with a central tendency of approximately 0.25. This body mass scaling is consistent with both the model of elastic similarity, and a model combining dynamic similarity with available metabolic power.
4. Even after controlling for body size or temperature, a substantial amount of inter-specific variation in running speed remains. Species with certain lifestyles [e.g. nomadic group predators, species which forage at extreme (>60 °C) temperatures] may have been selected for faster running speeds.
5. Although ants have a similar scaling exponent to mammals for the running speed allometry, they run slower than predicted compared with a hypothetical mammal of similar size. This may in part reflect physiological differences between invertebrates and vertebrates. 相似文献
26.
Trophoblast Cell Fusion and Differentiation Are Mediated by Both the Protein Kinase C and A Pathways
The syncytiotrophoblast of the human placenta is an epithelial barrier that interacts with maternal blood and is a key for the transfer of nutrients and other solutes to the developing fetus. The syncytiotrophoblast is a true syncytium and fusion of progenitor cytotrophoblasts is the cardinal event leading to the formation of this layer. BeWo cells are often used as a surrogate for cytotrophoblasts, since they can be induced to fuse, and then express certain differentiation markers associated with trophoblast syncytialization. Dysferlin, a syncytiotrophoblast membrane repair protein, is up-regulated in BeWo cells induced to fuse by treatment with forskolin; this fusion is thought to occur through cAMP/protein kinase A-dependent mechanisms. We hypothesized that dysferlin may also be up-regulated in response to fusion through other pathways. Here, we show that BeWo cells can also be induced to fuse by treatment with an activator of protein kinase C, and that this fusion is accompanied by increased expression of dysferlin. Moreover, a dramatic synergistic increase in dysferlin expression is observed when both the protein kinase A and protein kinase C pathways are activated in BeWo cells. This synergy in fusion is also accompanied by dramatic increases in mRNA for the placental fusion proteins syncytin 1, syncytin 2, as well as dysferlin. Dysferlin, however, was shown to be dispensable for stimulus-induced BeWo cell syncytialization, since dysferlin knockdown lines fused to the same extent as control cells. The classical trophoblast differentiation marker human chorionic gonadotropin was also monitored and changes in the expression closely parallel that of dysferlin in all of the experimental conditions employed. Thus different biochemical markers of trophoblast fusion behave in concert supporting the hypothesis that activation of both protein kinase C and A pathways lead to trophoblastic differentiation. 相似文献
27.
TRANSFORMATION of allogenic lymphocytes in mixed cultures depends chiefly on an incompatibility between the lymphocyte donors at the major histocompatibility locus in man (HL-A), mouse (H-2) and rat (H-l)1. Although the mouse H-2 locus can be divided into several regions each of which controls one or more antigenic specificities2 and two or more subloci control HL-A antigens in man3, it is not known whether all parts of the major histocompatibility locus are equally important in eliciting transformation in mixed lymphocyte cultures. We now show that capacity to elicit lymphocyte transformation is different for different parts of the mouse H-2 locus. 相似文献
28.
Excised cotyledons of Pinus radiata D. Don cultured under shoot-forming(plus benzyladenine) and non shoot-forming (minus benzyladenine)conditions for 10 and 21 days were fed U-[14C]-glucose for 3h in the light followed by a 3 h chase period. The labellingof individual metabolites as well as 14C incorporation intoprotein was assessed. It was found that the general metabolicpatterns were qualitatively the same in shoot-forming and nonshoot-forming conditions, however, metabolism leading to respirationas well as to the synthesis of some amino acids and proteinsynthesis was enhanced in the shoot-forming cultures. (Received February 16, 1987; Accepted July 8, 1987) 相似文献
29.
Walter S. Persons IV Philip J. Currie 《Evolution; international journal of organic evolution》2015,69(4):857-862
Over the course of the last two decades, the understanding of the early evolution of feathers in nonavian dinosaurs has been revolutionized. It is now recognized that early feathers had a simple form comparable in general structure to the hairs of mammals. Insight into the prevalence of simple feathers throughout the dinosaur family tree has gradually arisen in tandem with the growing evidence for endothermic dinosaur metabolisms. This has led to the generally accepted opinion that the early feather coats of dinosaurs functioned as thermo insulation. However, thermo insulation is often erroneously stated to be a likely functional explanation for the origin of feathers. The problem with this explanation is that, like mammalian hair, simple feathers could serve as insulation only when present in sufficiently high concentrations. The theory therefore necessitates the origination of feathers en masse. We advocate for a novel origin theory of feathers as bristles. Bristles are facial feathers common among modern birds that function like mammalian tactile whiskers, and are frequently simple and hair‐like in form. Bristles serve their role in low concentrations, and therefore offer a feasible first stage in feather evolution. 相似文献
30.
Identification and functional characterization of the Arabidopsis Snf1‐related protein kinase SnRK2.4 phosphatidic acid‐binding domain 下载免费PDF全文
MAGDALENA M. JULKOWSKA FIONN MCLOUGHLIN CARLOS S. GALVAN‐AMPUDIA JOHANNA M. RANKENBERG DOROTA KAWA MARIA KLIMECKA MICHEL A. HARING TEUN MUNNIK EDGAR E. KOOIJMAN CHRISTA TESTERINK 《Plant, cell & environment》2015,38(3):614-624
Phosphatidic acid (PA) is an important signalling lipid involved in various stress‐induced signalling cascades. Two SnRK2 protein kinases (SnRK2.4 and SnRK2.10), previously identified as PA‐binding proteins, are shown here to prefer binding to PA over other anionic phospholipids and to associate with cellular membranes in response to salt stress in Arabidopsis roots. A 42 amino acid sequence was identified as the primary PA‐binding domain (PABD) of SnRK2.4. Unlike the full‐length SnRK2.4, neither the PABD‐YFP fusion protein nor the SnRK2.10 re‐localized into punctate structures upon salt stress treatment, showing that additional domains of the SnRK2.4 protein are required for its re‐localization during salt stress. Within the PABD, five basic amino acids, conserved in class 1 SnRK2s, were found to be necessary for PA binding. Remarkably, plants overexpressing the PABD, but not a non‐PA‐binding mutant version, showed a severe reduction in root growth. Together, this study biochemically characterizes the PA–SnRK2.4 interaction and shows that functionality of the SnRK2.4 PABD affects root development. 相似文献