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11.
F Moreira SMM Gheller RG Mondadori AS Varela Júnior CD Corcini T Lucia Jr 《Reproduction in domestic animals》2014,49(6):1074-1078
Leptin acts on energy metabolism, affecting reproductive functions through activation of its receptors in the brain and in reproductive organs. This study compared the presence of leptin and its receptor (ObR‐b) in hypothalamus neurons, endometrial glands and oocytes of culled swine females across ovarian statuses and parities. Immunohistochemistry was done in samples of uterus, ovaries and hypothalamus from 28 culled females, using polyclonal antibodies antileptin and ObR‐b. Immunolabelling was compared for sows categorized by parity at culling (0, 1, 2–4 and <4) and ovarian status (luteal and follicular phases of the oestrous cycle and with cysts). Immunolabelling for leptin and ObR‐b in neurons and oocytes was weaker in females with cysts (p < 0.05) than in those at the follicular phase. In endometrial glands, leptin immunolabelling was less intense in females with cysts (p < 0.05), but immunolabelling for ObR‐b was similar across ovarian statuses (p > 0.05). In sows culled with 2–4 parities, leptin immunolabelling in neurons and endometrial glands was more intense than in nulliparous females (p < 0.05). In comparison with sows culled at greater parities, ObR‐b immunolabelling for nulliparous females was less intense in endometrial glands and in oocytes (p < 0.05), but more intense in neurons (p < 0.05). Thus, in swine, the presence of leptin and ObR‐b varies across parities and is more intense in the uterus, ovaries and hypothalamus of females that were cycling before culling than in those having cystic ovaries. 相似文献
12.
In the Ultimatum Game, two players are offered a chance to win a certain sum of money. All they must do is divide it. The proposer suggests how to split the sum. The responder can accept or reject the deal. If the deal is rejected, neither player gets anything. The rational solution, suggested by game theory, is for the proposer to offer the smallest possible share and for the responder to accept it. If humans play the game, however, the most frequent outcome is a fair share. In this paper, we develop an evolutionary approach to the Ultimatum Game. We show that fairness will evolve if the proposer can obtain some information on what deals the responder has accepted in the past. Hence, the evolution of fairness, similarly to the evolution of cooperation, is linked to reputation. 相似文献
13.
Zidorn C Jöhrer K Ganzera M Schubert B Sigmund EM Mader J Greil R Ellmerer EP Stuppner H 《Journal of agricultural and food chemistry》2005,53(7):2518-2523
A dichloromethane extract of root celery yielded falcarinol, falcarindiol, panaxydiol, and the new polyacetylene 8-O-methylfalcarindiol. The structure of the new compound was established by one- and two-dimensional (1D and 2D) NMR, mass spectrometry, and optical rotation data. Nonpolar extracts of roots and bulbs of carrots, celery, fennel, parsley, and parsnip were investigated for their content of polyacetylenes by high-performance liquid chromatography with diode array detection (HPLC-DAD). All five species contained polyacetylenes, although carrots and fennel only in minor amounts. Additionally, the cytotoxicity of the four polyacetylenes against five different cell lines was evaluated by the annexin V-PI assay. Falcarinol proved to be the most active compound with a pronounced toxicity against acute lymphoblastic leukemia cell line CEM-C7H2, with an IC(50) of 3.5 micromol/L. The possible chemopreventive impact of the presented findings is discussed briefly. 相似文献
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Measurements of both front feet of slaughtered German Simmental cattle (17 heifers, 13 cows) were carried out to document the normal shape and size of the forelimb claws and to gain information about function and possible predisposition to disease. Only clinically normal feet were examined, and a standardised sole thickness of 5mm at the tip and 8mm in the heel region in both claws was established as a reference. The dorsal wall length, dorsal wall angle, heel length, height and width, sole and claw length and claw width, sole circumference and sole area were measured. After removal of the horn capsules, measurements of values at the level of the corium were carried out. The lateral front claws were wider and the medial claws longer than their partner claws. Overall, the sole surface areas and circumferences of the paired claws were similar, but were statistically larger in the medial claws. The front claws were characterised by long and high heel bulbs, and had a toe length:heel bulb length ratio of approximately 1.6:1. These properties, together with the musculo-tendinous attachment of the limbs to the trunk, are believed to provide better protection for the forelimb claws when standing or walking on hard surfaces. Functional mechanical relief of the medial front claws is probably best achieved by pairing the soles of the foot to the same level, which usually entails reduction of the lateral claw. For German Simmental cattle, a dorsal wall length of 75mm can be used as a guideline when trimming front and hind feet. 相似文献
16.
Chen CC Lamping KG Nuno DW Barresi R Prouty SJ Lavoie JL Cribbs LL England SK Sigmund CD Weiss RM Williamson RA Hill JA Campbell KP 《Science (New York, N.Y.)》2003,302(5649):1416-1418
Calcium ion (Ca2+) influx through voltage-gated Ca2+ channels is important for the regulation of vascular tone. Activation of L-type Ca2+ channels initiates muscle contraction; however, the role of T-type Ca2+ channels (T-channels) is not clear. We show that mice deficient in the alpha1H T-type Ca2+ channel (alpha(1)3.2-null) have constitutively constricted coronary arterioles and focal myocardial fibrosis. Coronary arteries isolated from alpha(1)3.2-null arteries showed normal contractile responses, but reduced relaxation in response to acetylcholine and nitroprusside. Furthermore, acute blockade of T-channels with Ni2+ prevented relaxation of wild-type coronary arteries. Thus, Ca2+ influx through alpha1H T-type Ca2+ channels is essential for normal relaxation of coronary arteries. 相似文献
17.
18.
Sigmund Schwimmer Horace K. Burr W. O. Harrington William J. Weston 《American Journal of Potato Research》1957,34(2):31-41
Russet Burbank potatoes that had been stored at 40°F. for 5 months after harvest were irradiated with 5,200 and 14,000 rad of Co60 gamma rays. In general, irradiation caused an accumulation of sugars. At 40°F., the sucrose level rose to nearly 3 times that of the control in 16 days following irradiation. Fructose and glucose showed smaller increases and the latter did not accumulate significantly in the tubers given the higher dose of gamma rays. At 70°F., the levels of sucrose and glucose in the irradiated tubers rose above those in the controls, the difference reaching a maximum in 4 days and then declining. Irradiation had no effect on loss of fructose at this temperature. Color of potato chips processed from the irradiated potatoes was in general darker than that of chips from control tubers. The storage-time pattern of color change resembled that of the reducing rather than total sugar. Fourteen thousand rad did not prevent initiation of germination in the tubers but did destroy their sprout-growth apparatus. Although the lower dosage did not prevent initiation and subsequent growth, it prevented the formation of secondary tubers, which appeared on the sprouted control tubers. Furthermore, unlike the controls, the low-dosage potatoes developed branching hair sprouts with no tendency toward apical dominance during the early stages of sprouting. The rate of greening of gamma-irradiated and illuminated tubers was significantly less than that of unirradiated illuminated controls. Evidence is presented that irradiation may increase the susceptibility of potatoes to attack by molds under some conditions. 相似文献
19.
An unusual outbreak of contagious ovine ecthyma 总被引:1,自引:0,他引:1
CD HAWKINS TM ELLIS MK DAVIES RL PEET J. PARKINSON 《Australian veterinary journal》1991,68(6):210-211
20.
The role of monooxygenases in detoxification of the pyrethroids cypermethrin and deltamethrin was examined. Four strains of sea lice (Lepeophtheirus salmonis Krøyer) with normal or moderately reduced sensitivity towards the pyrethroids were tested in bioassays by exposure to the pyrethroid alone and in combination with an oxygenase inhibitor, piperonyl butoxide (PBO). The normal (baseline) sensitivity was considered as the sensitivity range for the two most sensitive strains. Pre‐treatment with PBO elevated the sensitivity (P < 0.01) compared with groups exposed to the pyrethroid only. A positive, but not statistically significant, correlation between the activity of haem peroxidases and the pyrethroid concentration immobilizing 50% of the parasites was demonstrated (ρ = 0.500 for deltamethrin and ρ = 0.310 for cypermethrin). The results indicate that cytochrome P450 monooxygenases are involved in detoxification of pyrethroids in sea lice. 14C‐Deltamethrin was absorbed in a lesser amount in a group of sea lice exposed to a mixture of the compound and PBO than in a group exposed to 14C‐deltamethrin alone. A significant difference could be demonstrated both immediately after exposure (P < 0.01) and 24 h after exposure (P < 0.05). No significant differences were found between groups pre‐treated with PBO and groups exposed to 14C‐deltamethrin only. 14C‐Deltamethrin was taken up mainly through the cuticle, especially the cuticle on the extremities of the ventral surface, and subsequently distributed throughout the body of the parasite. Copyright © 2005 Society of Chemical Industry 相似文献