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41.
Three cases of pustular psoriaform dermatitis (pityriasis rosea) in pigs were clinically and histopathologically examined. Grossly, the affected skin was characterized by multiple, circumscribed lesions. Three pigs were the descendants derived from the same Landrace boar. Skin lesions expanded centrifugally to became ring-shaped plaques. There were no abnormal values in hematological and serum biochemical profiles. Histopathologically, the epidermis showed remarkable thickening. The dermal lesions were characterized by a prominent component of superficial and deep perivascular infiltration of eosinophils. Dilatation of microvasculature was accompanied with congested vessels. These results revealed that the etiology of pustular psoriaform dermatitis in pigs was associated with a hereditary predisposition derived from the specific boars. This dermatosis is histopathologically characterized by microcirculatory disturbances with infiltration of abundant eosinophils.  相似文献   
42.
The existence of a food-entrainable circadian oscillator (FEO) was examined in goldfish Carassius auratus. Single goldfish were exposed to light–dark (LD) 12:12 (lights on 06:00–18:00 h) and fed at 12:00 h (phase I). The photoperiod regime was shifted to constant light (LL) (phase II). The fish were then fed at 06:00 or at 18:00 h (phase III), and all fish were fasted (phase IV). In both groups, three out of eight fish exhibited food-anticipatory activity (FAA) in phases II and III, the free-running period (τ) of locomotor activity was approximately 24.0 h, and circadian rhythms of locomotor activity started to free-run from the previous FAA in phase IV, indicating the existence of an FEO. Next, single goldfish were exposed to LD 12:12 and were fed twice daily at 12:00 and 00:00 h (phase I). The photoperiod regime was shifted to LL (phase II), and the fish were fasted (phase III). In phase II, FAA was observed in three out of six fish for both feeding times. In phase III, a circadian rhythm of locomotor activity was observed in five fish, and circadian rhythms started to free-run from the previous feeding time (either 12:00 or 00:00 h) in three fish. These results suggest that individual goldfish can remember two daily feeding times.  相似文献   
43.
We performed a field experiment in thebiodegradation of heavy oil spilled from the Russian tankerNakhodka on a beach in the Sea of Japan. We collectedoil-contaminated cobbles and treated half with nitrogen andphosphorus slow-release fertilizers to stimulate microbialdegradation of the oil; the other half acted as unfertilizedcontrols. The cobbles were placed in porous acrylic vessels andsubmerged. We monitored changes in the oils, macronutrients,microbial community structure and amount of chlorophyll a. There were no significant differences in these criteriabetween the fertilized and unfertilized vessels, apart from anincrease in chlorophyll a in the fertilized vessels.However, there was a major intrinsic degradation of semi-volatile oil compounds in the unfertilized vessels; this occurred at a rate similar to that in the fertilized vessels, despite the low concentration of macronutrients in the seawater at the site.  相似文献   
44.
Lactoferrin (LF) is a ubiquitous protein which exists in milk, plasma, synovial fluids, cerebrospinal fluid and other biological fluids. LF is also well known as a natural immunomodulator. Recently, we found that bovine milk-derived LF (BLF) produced micro-opioid receptor-mediated analgesia. In this study, we examined whether oral administration of BLF causes anti-nociceptive and anti-inflammatory effects, and also whether it modulates LPS-induced TNF-alpha and IL-10 production in rat model of rheumatoid arthritis (RA), rat adjuvant arthritis. BLF was administrated once daily, starting 3 hr before (preventive experiment) or 19 days after (therapeutic experiment) adjuvant injection. In both experiments, BLF suppressed the development of arthritis and the hyperalgesia in the adjuvant-injected paw. The single-administered BLF produced a dose-dependent analgesia, which was reversed by naloxone, in the adjuvant arthritis rats. Both repeated and single administration of BLF suppressed TNF-alpha production and increased IL-10 production in the LPS-stimulated adjuvant arthritis rats. These results suggest that orally administered BLF has both preventive and therapeutic effects on the development of adjuvant-induced inflammation and pain. Moreover, the immunomodulatory properties of BLF, such as down-regulation of TNF-alpha and up-regulation of IL-10, could be beneficial in the treatment of RA. Thus, we concluded that LF can be safely used as a natural drug for RA patients suffering from joint pain.  相似文献   
45.
This study determined isotopic fractionation of nitrate-nitrogen during denitrification in riparian aquifer sediments by sequential-column experiments at two different water flow rates. The purpose was to discuss the relationships of nitrogen isotopic enrichment factor of denitrification, denitrification rate, and infiltrating condition in sediment. Sandy sediment and groundwater were collected from floodplain in the middle reach of the Tama River where nitrogen isotopic enrichment factor for denitrification had been measured in a result of previous field observation. The denitrification rates and the isotopic enrichment factors of nitrate-nitrogen were estimated at 2.1 mgN dry-kg?1 day?1 and ?32.9‰ during the low water flow condition, and at 3.5 mgN dry-kg?1 day?1 and ?34.1‰ during the high water flow condition. The calculated water flow rates of the present column experiments were 300–400 times higher than that of the field observation. Because of the fast flow rate, nitrate was expected to continuously pass though active denitrifying sites in the small pore spaces of sediment, and nitrate supply to denitrifers by infiltration flow transport greatly exceeded the supply by diffusion. The observed denitrification rates was proportional to Peclet number as the ratio of solute nitrate transport to the diffusion, and apparent nitrogen isotopic enrichment factors during denitrification of our column experiments were lower than those obtained from the field observation. This study showed that denitrification rate and apparent nitrogen isotopic enrichment factor of denitrification in sediment depended on Peclet number.  相似文献   
46.
Reactivity of wood charcoal with ozone   总被引:8,自引:0,他引:8  
We investigated the resistance of wood charcoal against ozone and estimated the half-life of the charcoal in air. The weight of wood charcoal prepared by the carbonization of Fagus crenata sawdust at 400°C (C-400) was not affected with up to 8.5% ozone while the charcoal prepared at 1000°C (C-1000) burned with 4.9% ozone. Pores with a diameter of approximately 100–200nm were observed on the surface of ozone-treated C-1000 by scanning electron microscopy, although no pores were found in ozone-treated C-400. The peak positions of the C1s spectra and the full width at half maximum of X-ray photoelectron spectrum peaks suggest that C-400 has an amorphous structure composed of aliphatic carbons and small aromatic molecules while C-1000 and activated charcoal (AC) are polyaromatic. It is likely that the aromatic layers of C-1000 and AC were destroyed and the edge carbon atoms were removed as CO or CO2 by ozone oxidation. We estimated the half-life of C-1000 with ozone in air to be about 50000 years by assuming that the weight of C-1000 decayed exponentially. Thus, it is suggested that wood charcoal is stable on a geological time scale.  相似文献   
47.
The effects of NO2 and O3 exposure alone or in combination were investigated with respect to the amino acid content and composition in kidney bean. The short-term exposure (up to 8 h) to NO2 at a concentration of 4.0 ppm alone or in combination with O3 at a concentration of 0.4 ppm induced a rapid increase in the total amino acid content among which glutamine accounted for most of the part. Total amino acid content was also increased by O3 exposure at 0.4 ppm after 2 hours’ lag period. Ammonium level became higher in the case of combined exposure to NO2 and O3, while it remained constant in the case of exposure to NO2 and O3 alone.

When the exposure period was extended to 2 to 7 days (long-term exposure), the increase in the content of the total amino acids was observed in most of treatments. Roots of the plants exposed to various concentrations of NO2 and O3 showed the most remarkable increase in the content of total amino acids. Asparagine, in place of glutamine, became a major amino acid. The percentage of asparagine was especially increased by the mixed exposure to NO2 and O3 These results indicate that glutamine which accumulates considerably in the early phase of the gas exposure (short-term exposure) seems to be gradually converted into other amino acids, mainly asparagine.

The correlation between the content of each amino acid, ammonium and total amino acids was calculated using data from the above experiment. Most of the amino acids in the primary and trifoliate leaves showed a high correlation with the total amino acids, suggesting that the changes in the amount of total amino acids caused by the air pollutants may be reflected not only by a particular amino acid, but also by an individual amino acid composing soluble metabolite pool. A high correlation was obtained among amino acids belonging to the serine family such as glYCine, serine, and cysteine.  相似文献   
48.
ABSTRACT:   To clarify the possible roles of gonadotropin-releasing hormone (GnRH) in the reproduction of Japanese flounder Paralichthys olivaceus , localization of salmon GnRH (sGnRH), chicken GnRH-II (cGnRH-II), and sea bream GnRH (sbGnRH) immunoreactive (ir) cell bodies and fibers in the brain and pituitary were examined together with follicle stimulating hormone (FSH) and luteinizing hormone (LH)-ir cells in the pituitary by immunohistochemistry. sGnRH-ir cell bodies were localized in the ventromedial part of the rostral olfactory bulb and cGnRH-II-ir cell bodies were restricted to the midbrain tegmentum, while sbGnRH-ir cell bodies were evident in the preoptic area. sGnRH-ir fibers were distributed throughout the brain, especially abundant in the forebrain. cGnRH-II-ir fibers were also scattered in many areas of the brain with abundance in the midbrain, but sbGnRH-ir fibers were observed in the preoptic–hypothalamic area and innervated the pituitary. In the pituitary, neither sGnRH-ir fibers nor cGnRH-II-ir fibers were found, but sbGnRH-ir fibers were profuse in the neurohypophysis and invaded the proximal pars distalis, targeting FSH and LH cells. These results suggest that three GnRH systems can play different physiological roles in the brain of Japanese flounder. Among them, sbGnRH is considered to be involved in reproduction by stimulating gonadotropin secretion, while sGnRH and cGnRH-II can function as a neurotransmitter and/or neuromodulator within the brain in this species.  相似文献   
49.
Immunohistochemical localization of orexin/hypocretin in the brain of a pleuronectiform fish, the barfin flounder Verasper moseri was examined as the first step in unraveling the possible function of the hormone in the brain. Orexin-A-like immunoreactive (ir) cell bodies were found to be located in the nucleus posterioris periventricularis (NPPv) of the hypothalamus, and orexin-A-like-ir fibers were detected not only in the hypothalamus but also extensively throughout the brain. The orexin-A-like-ir cell bodies did not project their fibers to the pituitary gland. Since melaninconcentrating hormone (MCH) and α-melanocyte-stimulating hormone (α-MSH) are suggested to regulate food intake in addition to orexin/hypocretin in the teleost fish, it was examined whether neural connections exist between orexin neurons and the MCH and α-MSH neurons in the barfin flounder brain by using double-staining immunohistochemistry. Some orexin-A-like-ir fibers were in close contact with the MCH-ir and α-MSH-ir cell bodies in the hypothalamus. Moreover, a few MCH-ir and α-MSH-ir fibers were in close contact with the orexin-A-like-ir cell bodies in the hypothalamus. These results suggest that reciprocal connections exist between the orexin and MCH neurons and between the orexin and α-MSH neurons in the brain of the barfin flounder.  相似文献   
50.
To elucidate the role of gonadotropin-releasing hormone (GnRH) in gonadal maturation in wild female Japanese flounder Paralichthys olivaceus, we monitored changes in the levels of seabream GnRH (sbGnRH) in the olfactory bulb, telencephalon, hypothalamus, and pituitary during ovarian development together with changes in plasma levels of testosterone (T), estradiol-17β (E2), and 17α, 20β-dihydroxy-4-pregnen-3-one (DHP). Fish were caught offshore of the northern mainland of Japan in the Pacific Ocean at 3- to 4-week intervals between April and September by gill net. The netted fish were categorized into six groups based on ovarian stages: previtellogenic (April–early May), early yolk (April–late May), late yolk (late May–June), early spawning (June–August), late spawning (September), and termination (September) stages. The gonadosomatic index significantly increased from the previtellogenic to early spawning stages and decreased thereafter. In the olfactory bulb, no significant differences were observed in sbGnRH levels among the developmental stages. In contrast, sbGnRH levels in the telencephalon and hypothalamus were very high in the previtellogenic stage, lower in the early spawning stage, and relatively high in latter stages. sbGnRH levels in the pituitary were high in the previtellogenic stage and low in the early spawning stage. In addition, the relatively high levels of pituitary sbGnRH were found together with high plasma T, E2, and DHP levels in fish in the late yolk stage. These results indicate that sbGnRH in the telencephalon, hypothalamus, and pituitary is involved in ovarian maturation and that sbGnRH may play an important role in the initiation of ovarian recrudescence in wild Japanese flounder.  相似文献   
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