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1.
We conducted 3 independent experiments to demonstrate functional G-coupled protein receptor 43 (GPR43) and GPR120 in bovine intramuscular (i.m.) and subcutaneous (s.c.) adipose tissues. We hypothesized that media volatile fatty acids and long-chain fatty acids would affect cAMP-activated protein kinase-alpha (AMPKα) protein expression and cAMP concentrations differently in i.m. and s.c. adipose tissue. Experiment 1: oleic acid (18:1n-9) decreased phosphorylated AMPKα protein (p-AMPKα) and the p-AMPKα/AMPKα protein ratio in i.m. preadipocytes, increased the p-AMPKα/AMPKα protein ratio in bovine satellite cells, and had no effect in s.c. preadipocytes. Experment 2: ex vivo explants from the 5th to 8th longissimus thoracic rib muscle section of Angus crossbred steers were cultured 48 hr in media containing 0.25 µM ciglitizone, 5 mM glucose, and 5 mM acetate, in the absence or the presence of 100 µM oleic acid. Oleic acid increased acetate incorporation into fatty acids and GPR43 gene expression in i.m. adipose tissue (P < 0.05), but oleic acid had no effect on fatty acid synthesis or GPR43 expression in s.c. adipose tissue. Experiment 3: fresh s.c. and i.m. adipose tissue from the 5th to 8th longissimus thoracic rib muscle section of Angus crossbred steers was transferred immediately to 6-well culture plates containing 3 mL of KHB/Hepes/5 mM glucose. Samples were preincubated with 0.5 mM theophylline plus 10 μM forskolin for 30 min, after which increasing concentrations of acetate or propionate (0, 10−3, 10−2.3, and 10−3 M) in the absence or the presence of 100 μM oleic acid or 100 µM palmitic acid (16:0) were added to the incubation media. Acetate had no effect on forskolin-stimulated cAMP production in s.c. adipose tissue but decreased cAMP in i.m. adipose tissue (P < 0.05); this indicates a functional GPR43 receptor in i.m. adipose tissue. The combination of 10−2 M acetate and oleic acid decrease cAMP production in s.c. adipose tissue, consistent with GPR120 receptor activity, but oleic acid and palmitic acid attenuated the depression of cAMP production caused by acetate in i.m. adipose tissue. Palmitic acid depressed cAMP production in s.c. adipose tissue, and increased cAMP production in i.m. adipose tissue (P < 0.05). Propionate had no effect on cAMP production in s.c. or i.m. adipose tissue. These results provide evidence for functional GPR43 receptors in i.m. adipose tissue and GPR120 receptors in s.c. adipose tissue, both of which would suppress lipolysis.  相似文献   
2.
Abutilon theophrasti (velvetleaf) is a widespread and problematic annual weed. Greenhouse and field experiments were conducted to investigate the effects of different cutting methods on the viability of A. theophrasti seeds. Three cutting methods were assessed: (1) Entire plant cut and dried (EPD)—plants were cut at soil level and dried with capsules attached on the greenhouse bench or soil surface for 4 weeks; (2) capsules detached and dried (CD)—capsules were removed from plants and dried for 4 weeks; and (3) capsules detached and tested while fresh (CF)—a control treatment. Before drying, the developmental stage (stage one, dark green; stage two, light green; stage three, yellowish-green; or stage four, black with the slightly open capsule) and age (days after flowering, DAF) of each capsule was recorded. Seed viability was measured immediately in the CF treatment and after the 4-week drying period in the EPD and CD treatments. No seeds in the EPD and CD treatments were viable when harvested at the first developmental stage (1–8 DAF) in either experiment, but 100% of seeds in the CF treatment in the field were viable when harvested at 8 DAF. In both greenhouse and field experiments, seeds attained full viability at earlier harvest ages in CF than in EPD or CD treatments, suggesting that seeds might become viable relatively early in development but lose viability if allowed to dry. These findings could be applied to optimise late-season mechanical control of A. theophrasti.  相似文献   
3.
By in situ chromosomal hybridization, the GM-CSF and FMS genes were localized to human chromosome 5 at bands q23 to q31, and at band 5q33, respectively. These genes encode proteins involved in the regulation of hematopoiesis, and are located within a chromosome region frequently deleted in patients with neoplastic myeloid disorders. Both genes were deleted in the 5q-chromosome from bone marrow cells of two patients with refractory anemia and a del(5)(q15q33.3). The GM-CSF gene alone was deleted in a third patient with acute nonlymphocytic leukemia (ANLL) who has a smaller deletion, del(5)(q22q33.1). Leukemia cells from a fourth patient who has ANLL and does not have a del(5q), but who has a rearranged chromosome 5 that is missing bands q31.3 to q33.1 [ins(21;5)(q22;q31.3q33.1)] were used to sublocalize these genes; both genes were present on the rearranged chromosome 5. Thus, the deletion of one or both of these genes may be important in the pathogenesis of myelodysplastic syndromes or of ANLL.  相似文献   
4.
We have studied two-body correlations of atoms in an expanding cloud above and below the Bose-Einstein condensation threshold. The observed correlation function for a thermal cloud shows a bunching behavior, whereas the correlation is flat for a coherent sample. These quantum correlations are the atomic analog of the Hanbury Brown Twiss effect. We observed the effect in three dimensions and studied its dependence on cloud size.  相似文献   
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Anoestrous dairy cows in seasonally calving herds in the Macalister Irrigation District of Gippsland, Victoria were treated at the start of the mating period with a progesterone releasing intravaginal device (CIDR). The CIDR was inserted for 7 days and 400 IU of PMSG was injected intramuscularly at removal. There was no clinically useful difference among cows receiving the CIDR, a placebo and untreated cows in the interval from treatment to either first oestrus or conception, the conception rate to first service or percent pregnant by the end of mating. Analyses of data from 2-year-old cows, older cattle, cows calved at least 45 days or cows calved at least 55 days and cows treated 3 weeks after the start of mating did not show improved reproductive performance following treatment with the CIDR.  相似文献   
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Various plants and fungi have evolved ingenious devices to disperse their spores. One such mechanism is the cavitation-triggered catapult of fern sporangia. The spherical sporangia enclosing the spores are equipped with a row of 12 to 13 specialized cells, the annulus. When dehydrating, these cells induce a dramatic change of curvature in the sporangium, which is released abruptly after the cavitation of the annulus cells. The entire ejection process is reminiscent of human-made catapults with one notable exception: The sporangia lack the crossbar that arrests the catapult arm in its returning motion. We show that much of the sophistication and efficiency of the ejection mechanism lies in the two very different time scales associated with the annulus closure.  相似文献   
10.
Sixty-eight cases of uterine prolapase in pastured dairy cows were treated in 2 consecutive spring calving seasons in East Gippsland, Victoria. Fifty cows survived (73.5%). Of 43 cows available for followup, 36 (84%) conceived in the mating period following the prolapse, taking 10 d longer to conceive than herd mates that calved on the same day. Three of the 36 cows (8%) that conceived, aborted, this occurring in the middle trimester of pregnancy. No prolapses occurred at the following calving but one case had suffered uterine prolapse 2 years previously. The conclusions drawn from these observations are that cows with uterine prolapse have a good chance of surviving if treated, that treatment is cost-effective, that uterine prolapse is unlikely to reoccur and treated cows have a good chance of conceiving. The veterinarians involved in this investigation were reasonably accurate in their ability to predict long term survival but not as good in predicting ability to conceive again.  相似文献   
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