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排序方式: 共有885条查询结果,搜索用时 31 毫秒
41.
Bela M Arosalo Marja Raekallio Minna Rajamäki Elina Holopainen Tuulia Kastevaara Hanna Salonen Satu Sankari 《Acta veterinaria Scandinavica》2007,49(1):4
Background
The aim of the study was to investigate urine matrix metalloproteinase (MMP-2 and -9) activity, alkaline phosphatase/creatinine (U-AP/Cr) and gamma-glutamyl-transpeptidase/creatinine (U-GGT/Cr) ratios, glucose concentration, and urine protein/creatinine (U-Prot/Cr) ratio and to compare data with plasma MMP-2 and -9 activity, cystatin-C and creatinine concentrations in colic horses and healthy controls. Horses with surgical colic (n = 5) were compared to healthy stallions (n = 7) that came for castration. Blood and urine samples were collected. MMP gelatinolytic activity was measured by zymography. 相似文献42.
Partanen K Siljander-Rasi H Pentikäinen J Pelkonen S Fossi M 《Archives of animal nutrition》2007,61(5):336-356
Two hundred and forty piglets were used in a 2 x 6 factorial experiment to study the effects of weaning age (26 or 36 d) and four formic acid-based feed additives on the performance of pigs from weaning to slaughter. Either formic acid (F) or a mixture of formic acid, propionic acid, and potassium sorbate (FPS) or a mixture of formic acid, propionic acid, and sodium benzoate (FPB) or formic acid in a diatomaceous earth carrier (FD) were added to the diets of weaned piglets (from weaning to 60 d of age) and growing (18-46 kg) and finishing pigs (46-107 kg) to provide 8, 6, and 6 g acid per kg feed, respectively. The negative control treatment's (C) diets contained no growth promoters, whereas the positive control treatment's weaner and grower diets were supplemented with 40 mg/kg of avilamycin (A). The piglets weaned at the age of 26 and 36 d weighed 7.6 and 10.7 kg at weaning (p < 0.001), and 18.5 and 17.9 kg at the age of 60 d (p > 0.05), respectively. There was a weaning age x feed additive interaction in the weight gain of piglets after weaning (p < 0.05). The weight gain of piglets weaned on day 26 was enhanced by A, FPS, and FD (p < 0.05), and that of piglets weaned on day 36 by A and FPB (p < 0.05). The feed conversion ratio was not affected by weaning ages but was decreased in groups A, F, FBS, and FPB (p < 0.05). The severity of post-weaning diarrhoea was less in groups A, F, FPS, and FD than in C (p < 0.05). In piglets weaned on day 26, faecal water content and the total Escherichia coli count were highest 9 d after weaning. The total E. coli count was reduced only by FD (p < 0.05). Increased faecal water content was characterized by increased faecal Na+ and decreased K+ concentrations. Weaning age did not influence performance or carcass quality in the growing-finishing pigs. Feed additives did not affect weight gain in the growing pigs, but FPS and FPB enhanced weight gain during finishing period and total fattening (p < 0.05). In summary, the pigs' growth performance from weaning to slaughter was not affected by weaning age but it was enhanced by mixtures of formic and propionic acids with small amounts of sorbate or benzoate. 相似文献
43.
44.
Kaleczyc J Timmermans JP Majewski M Lakomy M Scheuermann DW 《Histochemistry and cell biology》1999,111(3):217-228
Immunohistochemical studies have been performed to investigate the occurrence and coexistence of two catecholamine-synthesising
enzymes, tyrosine hydroxylase and dopamine-β-hydroxylase, and several neuropeptides, including neuropeptide Y, vasoactive
intestinal polypeptide, Leu5-enkephalin, somatostatin, calcitonin gene-related peptide and substance P, in nerve fibres supplying porcine accessory genital
glands, the seminal vesicles, prostate (body and the disseminated part) and bulbourethral glands. Three major populations
of nerve fibres supplying non-vascular elements of the glands have been distinguished (from the largest to the smallest one):
(1) noradrenergic fibres, the majority of which contain Leu5-enkephalin, neuropeptide Y or, to a lesser extent, somatostatin, (2) non-noradrenergic, putative cholinergic fibres containing
vasoactive intestinal polypeptide, neuropeptide Y and/or somatostatin and, (3) non-noradrenergic, presumably sensory fibres,
containing calcitonin gene-related peptide and substance P. Whilst the coexistence patterns within nerves supplying particular
glands are similar, the density of innervation varies between the organs. The innervation of the seminal vesicles and prostatic
body is more developed than that of the disseminated part of the prostate and bulbourethral glands. The majority of noradrenergic
fibres related to blood vessels contain neuropeptide Y only, while the non-noradrenergic nerves contain mainly vasoactive
intestinal polypeptide. The possible function and origin of particular nerve fibre populations are discussed.
Accepted: 16 November 1998 相似文献
45.
Järvenpää M Lindström K 《Proceedings. Biological sciences / The Royal Society》2004,271(1555):2361-2365
Eutrophication as a result of human activity has resulted in increased algal blooms and turbidity in aquatic environments. We investigated experimentally the effect of algal turbidity on the mating system and sexual selection in the sand goby, Pomatoschistus minutus (Pallas), a marine fish with a resource-defence mating system and paternal care. Owing to male-male competition and female choice, large males can monopolize multiple mates, while some males do not achieve mating at all. We show that the number of eggs laid was the same in both turbid and clear tanks but that mating success was more evenly distributed among males in turbid than in clear water. The opportunity for sexual selection was lower in turbid conditions. In turbid conditions mating success was less skewed towards large males. Our results suggest that increased turbidity can change mating systems and decrease the opportunity for sexual selection as well as selection intensity. 相似文献
46.
Oomen CJ Hoogerhout P Bonvin AM Kuipers B Brugghe H Timmermans H Haseley SR van Alphen L Gros P 《Journal of molecular biology》2003,328(5):1083-1089
We present an in silico, structure-based approach for design and evaluation of conformationally restricted peptide-vaccines. In particular, we designed four cyclic peptides of ten or 11 residues mimicking the crystallographically observed beta-turn conformation of a predicted immunodominant loop of PorA from Neisseria meningitidis. Conformational correctness and stability of the peptide designs, as evaluated by molecular dynamics simulations, correctly predicted the immunogenicity of the peptides. We observed a peptide-induced functional antibody response that, remarkably, exceeded the response induced by the native protein in outer membrane vesicles, without losing specificity for related strains. The presented approach offers tools for a priori design and selection of peptide-vaccine candidates with full biological activity. This approach could be widely applicable: to outer membrane proteins of Gram-negative bacteria, and to other epitopes in a large range of pathogens. 相似文献
47.
A novel type of deubiquitinating enzyme 总被引:1,自引:0,他引:1
Evans PC Smith TS Lai MJ Williams MG Burke DF Heyninck K Kreike MM Beyaert R Blundell TL Kilshaw PJ 《The Journal of biological chemistry》2003,278(25):23180-23186
A previous report from this laboratory described two novel proteins that have sequence similarity to A20, a negative regulator of NF-kappaB (Evans, P. C., Taylor, E. R., Coadwell, J., Heyninck, K., Beyaert, R., and Kilshaw, P. J. (2001) Biochem. J. 357, 617-623). One of these molecules, cellular zinc finger anti-NF-kappaB (Cezanne), a 100-kDa cytoplasmic protein, also suppressed NF-kappaB. Here we demonstrate that Cezanne is a novel deubiquitinating enzyme, distinct from the two known families of deubiquitinases, Types I and II. We show that Cezanne contains an N-terminal catalytic domain that belongs to the recently discovered ovarian tumor protein (OTU) superfamily, a group of proteins displaying structural similarity to cysteine proteases but having no previously described function. Recombinant Cezanne cleaved ubiquitin monomers from linear or branched synthetic ubiquitin chains and from ubiquitinated proteins. Mutation of a conserved cysteine residue in the catalytic site of the proteolytic domain caused Cezanne to co-precipitate polyubiquitinated cellular proteins. We also provide evidence for an additional ubiquitin binding site in the C-terminal part of the molecule. Our data provide the first demonstration of functional activity among OTU proteins. 相似文献
48.
Visapää I Fellman V Vesa J Dasvarma A Hutton JL Kumar V Payne GS Makarow M Van Coster R Taylor RW Turnbull DM Suomalainen A Peltonen L 《American journal of human genetics》2002,71(4):863-876
GRACILE (growth retardation, aminoaciduria, cholestasis, iron overload, lactacidosis, and early death) syndrome is a recessively inherited lethal disease characterized by fetal growth retardation, lactic acidosis, aminoaciduria, cholestasis, and abnormalities in iron metabolism. We previously localized the causative gene to a 1.5-cM region on chromosome 2q33-37. In the present study, we report the molecular defect causing this metabolic disorder, by identifying a homozygous missense mutation that results in an S78G amino acid change in the BCS1L gene in Finnish patients with GRACILE syndrome, as well as five different mutations in three British infants. BCS1L, a mitochondrial inner-membrane protein, is a chaperone necessary for the assembly of mitochondrial respiratory chain complex III. Pulse-chase experiments performed in COS-1 cells indicated that the S78G amino acid change results in instability of the polypeptide, and yeast complementation studies revealed a functional defect in the mutated BCS1L protein. Four different mutations in the BCS1L gene have been reported elsewhere, in Turkish patients with a distinctly different phenotype. Interestingly, the British and Turkish patients had complex III deficiency, whereas in the Finnish patients with GRACILE syndrome complex III activity was within the normal range, implying that BCS1L has another cellular function that is uncharacterized but essential and is putatively involved in iron metabolism. 相似文献
49.
50.
Photoinhibition of photosystem II was studied in vivo with bean (Phaseolus vulgaris) plants grown in the presence of 0.3 (control), 4, or 15 microM Cu(2+). Although photoinhibition, measured in the presence of lincomycin to block concurrent recovery, is faster in leaves of Cu(2+)-treated plants than in control leaves, thylakoids isolated from Cu-treated plants did not show high sensitivity to photoinhibition. Direct effects of excess Cu(2+) on chloroplast metabolism are actually unlikely, because the Cu concentration of chloroplasts of Cu-treated plants was lower than that of their leaves. Excess Cu in the growth medium did not cause severe oxidative stress, collapse of antioxidative defenses, or loss of photoprotection. Thus, these hypothetical effects can be eliminated as causes for Cu-enhanced photoinhibition in intact leaves. However, Cu treatment lowered the leaf chlorophyll (Chl) concentration and reduced the thylakoid membrane network. The loss of Chl and sensitivity to photoinhibition could be overcome by adding excess Fe together with excess Cu to the growth medium. The addition of Fe lowered the Cu(2+) concentration of the leaves, suggesting that Cu outcompetes Fe in Fe uptake. We suggest that the reduction of leaf Chl concentration, caused by the Cu-induced iron deficiency, causes the high photosensitivity of photosystem II in Cu(2+)-treated plants. A causal relationship between the susceptibility to photoinhibition and the leaf optical density was established in several plant species. Plant species adapted to high-light habitats apparently benefit from thick leaves because the rate of photoinhibition is directly proportional to light intensity, but photosynthesis becomes saturated by moderate light. 相似文献