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11.
Generally, sika deer conceive a single fetus, but approximately 80% of pregnant females have two corpora lutea (CLs). The function of the accessory CL (ACL) is unknown; moreover, the process of ACL formation is unclear, and understanding this is necessary to know its role. To elucidate the process of ACL formation, the ovarian dynamics of six adult Hokkaido sika deer females were examined ultrasonographically together with peripheral estradiol-17β and progesterone concentrations. ACLs formed in three females that conceived at the first estrus of the breeding season, but not in those females that conceived at the second estrus. After copulation, postconception ovulation of the dominant follicle of the first wave is induced by an increase in estradiol-17β, which leads to formation of an ACL. A relatively low concentration of progesterone after the first estrus of the breeding season is considered to be responsible for the increase in estradiol-17β after copulation.  相似文献   
12.
The diagnosis of gall bladder mucoceles (GM) in dogs has become increasingly frequent in veterinary medicine. Primary breed-specific hyperlipidaemia is reported in Shetland Sheepdogs and Miniature Schnauzers, breeds in which GM are known to occur more frequently than in other breeds. The objective of this study was to evaluate the association between GM and hyperlipidaemia in dogs. The study design was a retrospective case control study. Medical records of dogs diagnosed with GM at the Veterinary Medical Centre of The University of Tokyo between 1 April 2007 and 31 March 2012, were reviewed.Fifty-eight dogs with GM and a record of either serum cholesterol, triglyceride, or glucose concentrations were included in the study. Hypercholesterolaemia (15/37 cases; odds ratio [OR]: 2.92; 95% confidence interval [CI]: 1.02–8.36) and hypertriglyceridaemia (13/24 cases; OR: 3.55; 95% CI:1.12–15.91) showed significant association with GM. Pomeranians (OR: 10.69), American Cocker Spaniels (OR: 8.94), Shetland Sheepdogs (OR: 6.21), Miniature Schnauzers (OR: 5.23), and Chihuahuas (OR: 3.06) were significantly predisposed to GM. Thirty-nine out of 58 cases had at least one concurrent disease, including pancreatitis (five cases), hyperadrenocorticism (two cases), and hypothyroidism (two cases). A significant association between GM and hyperlipidaemia was confirmed, suggesting that hyperlipidaemia may play a role in the pathogenesis of GM.  相似文献   
13.
Investigation of the metabolism of [(14)C]pyriproxyfen [4-phenoxyphenyl (R,S)-2-(2-pyridyloxy)propyl ether] in tomato fruits (Lycopersicon esculentum Mill. cv. Ponterosa) was conducted by topical application of acetonitrile solution or emulsifiable concentration formulation three times at 35, 21, and 7 days before harvest. Most of the radioactivity remained on the fruit surface or in the plant tissues as intact pyriproxyfen with minor metabolites formed via hydroxylation at the 4'-position of the phenoxy ring or cleavage of ether linkages. The biomimic chemical oxidation model using iron porphyrin as a catalyst and hydrogen peroxide was found to well reproduce the primary metabolites detected in the metabolism study. The electrophilic reaction indices obtained by AM1 molecular orbital calculations supposing involvement of cytochrome P-450 were successfully applied to evaluate the potentially higher reactive sites in pyriproxyfen.  相似文献   
14.
The structure of Escherichia coli succinate dehydrogenase (SQR), analogous to the mitochondrial respiratory complex II, has been determined, revealing the electron transport pathway from the electron donor, succinate, to the terminal electron acceptor, ubiquinone. It was found that the SQR redox centers are arranged in a manner that aids the prevention of reactive oxygen species (ROS) formation at the flavin adenine dinucleotide. This is likely to be the main reason SQR is expressed during aerobic respiration rather than the related enzyme fumarate reductase, which produces high levels of ROS. Furthermore, symptoms of genetic disorders associated with mitochondrial SQR mutations may be a result of ROS formation resulting from impaired electron transport in the enzyme.  相似文献   
15.
More than half of orally administered N-cyclohexyl linoleamide-car-boxyl-C(14) yl-CI was recovered from feces of rats, and 30 to 50 percent of the absorbed carbon-14 activity was excreted in urine. N-Cyclohexyl linoleamide had an inhibitory eflect on the absorption of cholesterol from the thoracic duct and caused a decrease in the deposition of cholesterol in the livers of rats that had been fed cholesterol.  相似文献   
16.
By using an ionic liquid of 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide, we uniformly dispersed single-walled carbon nanotubes (SWNTs) as chemically stable dopants in a vinylidene fluoride-hexafluoropropylene copolymer matrix to form a composite film. We found that the SWNT content can be increased up to 20 weight percent without reducing the mechanical flexibility or softness of the copolymer. The SWNT composite film was coated with dimethyl-siloxane-based rubber, which exhibited a conductivity of 57 siemens per centimeter and a stretchability of 134%. Further, the elastic conductor was integrated with printed organic transistors to fabricate a rubberlike active matrix with an effective area of 20 by 20 square centimeters. The active matrix sheet can be uniaxially and biaxially stretched by 70% without mechanical or electrical damage. The elastic conductor allows for the construction of electronic integrated circuits, which can be mounted anywhere, including arbitrary curved surfaces and movable parts, such as the joints of a robot's arm.  相似文献   
17.
Fast skeletal light meromyosins (LMMs) of white croaker and walleye pollack were prepared in our expression system using Escherichia coli and determined for their polymer-forming ability and thermodynamic properties by using sodium dodecyl sulfate polyacrylamide gel electrophoresis and differential scanning calorimetry (DSC), respectively. White croaker LMM formed dimer by heating at 80 degrees C and showed only a single peak at 32.1 degrees C of temperature transition in DSC. On the other hand, walleye pollack LMM hardly formed polymer and showed four peaks at 27.7, 30.5, 35.8, and 43.9 degrees C. When Cys525 of white croaker LMM was replaced by alanine, this point-mutated LMM showed no change in its DSC profile but formed no dimer upon heating, suggesting a possible role of Cys525 in dimer formation. On the other hand, walleye pollack LMM where Cys491 was substituted by alanine changed its DSC profile, showing four peaks at 27.9, 29.1, 38.4, and 43.9 degrees C. However, this point-mutated LMM formed no dimer upon heating as in the case of native LMM. These results suggest that cysteine residue(s) participates in thermal gel formation of LMM when it locates in a suitable position of the sequence.  相似文献   
18.
Present analytical methods to quantify lignin in herbaceous plants are not totally satisfactory. A spectrophotometric method, acetyl bromide soluble lignin (ABSL), has been employed to determine lignin concentration in a range of plant materials. In this work, lignin extracted with acidic dioxane was used to develop standard curves and to calculate the derived linear regression equation (slope equals absorptivity value or extinction coefficient) for determining the lignin concentration of respective cell wall samples. This procedure yielded lignin values that were different from those obtained with Klason lignin, acid detergent acid insoluble lignin, or permanganate lignin procedures. Correlations with in vitro dry matter or cell wall digestibility of samples were highest with data from the spectrophotometric technique. The ABSL method employing as standard lignin extracted with acidic dioxane has the potential to be employed as an analytical method to determine lignin concentration in a range of forage materials. It may be useful in developing a quick and easy method to predict in vitro digestibility on the basis of the total lignin content of a sample.  相似文献   
19.
A tracer experiment using synthesized labeled lignin precursors was designed to confirm the actual biosynthetic pathway for syringyl lignin. Tetradeuteroferulic acid-[8-D, 3-OCD(3)] and heptadeuterosinapic acid-[8-D, 3,5-OCD(3)] were synthesized and fed to shoots of robinia (Robinia pseudoacacia) and oleander (Nerium indicum) trees. The incorporation of each labeled precursor into lignin was traced by gas chromatography-mass spectrometry. The synthesized sinapic acid, in which both methoxy groups were labeled, was useful in monitoring the conversion of sinapic acid into syringyl lignin. When heptadeuterosinapic acid was fed, syringyl units containing seven deuterium labels were detected. The results of this study support the traditionally accepted pathway that sinapic acid is converted to sinapyl alcohol via sinapoyl-CoA in robinia and oleander.  相似文献   
20.
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