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31.
Ketosis is found in various pathophysiological conditions, including diabetes and starvation, that are accompanied by suppression of gonadal activity. The aim of the present study was to determine the role of ketone body in the brain in regulating pulsatile luteinizing hormone (LH) secretion in female rats. Injection of 3-hydroxybutyrate (3HB), a ketone body, into the fourth cerebroventricle (4V) induced suppression of pulsatile LH secretion in a dose-dependent manner in ovariectomized (OVX) rats with an estradiol (E2) implant producing diestrus plasma E2 levels. Plasma glucose and corticosterone levels increased immediately after the 4V 3HB injection, suggesting that the treatment caused a hunger response. The 3HB-induced suppression of LH pulses might be mediated by noradrenergic inputs to the hypothalamic paraventricular nucleus (PVN) because a local injection of α-methyl- p-tyrosine, a catecholamine synthesis inhibitor, into the PVN blocked 3HB-induced suppression of LH pulses and PVN noradrenaline release was increased by 4V 3HB injection in E2-primed OVX rats. These results suggest that ketone body sensed by a central energy sensor in the hindbrain may suppress gonadotropin release via noradrenergic inputs to the PVN under ketosis.  相似文献   
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Sweet wheat (SW), which lacks functional granule-bound starch synthase I (GBSSI) and starch synthase IIa (SSIIa), accumulates high levels of free sugars in immature seeds. Here, we examined the effects of the lack of these two enzymes on mature kernel composition. Whole grain flour of SW had higher levels of sugars, particularly maltose, slightly higher ash and protein content, approximately two to three times higher lipid levels, and about twice as much total dietary fiber as parental or wild-type lines. Considerably higher levels of low-molecular-weight soluble dietary fiber (LMW-SDF), largely consisting of fructan, were also detected in SW. Although there were no differences in total amino acid levels, the free amino acid content of SW was approximately 4-fold higher than that of wild type, and the levels of certain free amino acids such as proline were particularly high. Thus, we were able to clearly demonstrate that the lack of GBSSI and SSIIa caused dramatic changes in mature seed composition in SW. These compositional changes suggest that SW flour may provide health benefits when used as a food ingredient.  相似文献   
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Malic enzymes have been considered to play a key role in energy metabolism for nitrogenase reaction in bacteroids. To elucidate the physiological role of the malic enzymes in Bradyrhizobium japonicum bacteroids, a putative malic enzyme gene Bjtme1 was cloned by polymerase chain reaction (PCR) using degenerated primers from conserved regions of the protein sequences of bacterial malic enzymes and draft sequence data of the Bradyrhizobium japonicum USDA110 genome sequence project. To confirm the characteristics of the Bjtme1 gene, the protein encoded by this gene was over-expressed using a pET32a(+) system and it exhibited a NADP+-malic enzyme (EC 1.1.1.40) activity, indicating that Bjtme1 was the gene of the NADP+-malic enzyme. This is the first report on the cloning and characterization of the NADP+-malic enzyme gene from B. japonicum, and the gene structure was compared with that of NADP+-malic enzyme genes of other rhizobia.  相似文献   
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Variations in parallel-to-grain static shear strength and perpendicular-to-grain tensile strength of Scots pine wood from mature stands in Finland and Sweden were studied by means of linear mixed model analyses. Approximately 35% of the total variation in shear strength could be described with readily available independent background variables; if the basic density was included, approximately two-thirds of the total variation could be controlled. In tensile strength perpendicular to grain, only approximately one-fourth of the total variation could be described with the respective background variables; the property was found to be independent on wood density, and the reasons for the absence of strength–density relationship are discussed.  相似文献   
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In this paper, we investigate how the innovation expectations of public financiers are related to realized patents. The analysis is based on a novel data set of collaborative R&D projects subsidized by the Finnish Agency of Technology and Innovation (Tekes) and the European Regional Development Fund (ERDF) during the period 2000–2004. Innovation expectations are measured using reports submitted by Tekes experts during ex ante assessments of projects. Our probit model results reveal that Tekes' patent expectations are positively related to realized patents for projects led by private firms (but not by public organizations). For large organizations, Tekes' innovation expectations are better at predicting patenting.  相似文献   
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A 4-year-old male Shiba dog initially presented with pain of an undetermined origin and hypersensitivity to touch. Seven days later, the dog developed ataxia, hind-leg weakness and knuckling. The dog died on 20 days after presentation. Postmortem examination revealed a mass in the body of thoracic vertebra. Histopathologically, the mass consisted of granulomatous inflammation, including fungal organisms that were immunohistochemically positive for Candida albicans. Similar granulomatous lesions were observed in the systemic lymph nodes, kidneys, pancreas, spleen, prostate gland, thyroid glands and heart. This case was diagnosed as systemic candidiasis with spondylitis.  相似文献   
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In this report, we present a series of cases of thermal burns (scalds) in dogs resulting from exposure to hot water from a garden hose that had been lying in the sun. These dogs typically inhabited the southern and western regions of the USA, where the recorded high temperatures often exceed 32°C (90°F) during the warm summer months. Dogs with thermal scald injury in these cases presented with linear thermal burns along the dorsum, in addition to a variety of other macroscopic lesions that were dependent upon the degree of burn exposure and ranged from local erythema to ulcerated, necrotic and sloughing skin. Chronic, healed wounds were often alopecic, with markedly thickened skin and characteristically smooth and glassy scar tissue formation. Histologically, the lesions of thermal scald injury in these dogs were indistinguishable from any other second or third degree burn, and consisted of full-thickness dermal and epidermal necrosis with occasional fibrinoid necrosis of vessel walls, vasculitis and intravascular thrombosis. Here, we closely examine 10 cases of dogs with dorsal thermal burns collected from Texas, Arizona, California, Utah, Nevada, Indiana, Michigan and North Carolina and propose the term 'garden hose scalding syndrome (GHS)' to describe this unique type of scald injury.  相似文献   
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