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91.
Shinri Hosoi Hiroshi Yoshikado George Gaidajis Kazuhiko Sakamoto 《Water, air, and soil pollution》2011,215(1-4):105-116
Ambient concentrations of photochemical oxidants (Ox) averaged throughout all ambient monitoring stations in Japan have increased slightly during the past two decades despite decreasing emissions of oxidant precursors such as NOx and hydrocarbons. In the Kanto area of Japan, which is heavily populated and industrialized, Ox concentrations are often high, especially in late spring and summer, and a photochemical smog warning is frequently issued. Although the north Kanto area is about 150 km from the southern metropolitan area, and, moreover, local emissions of precursors are limited because of its agricultural and forested character, high Ox concentration levels (>120 ppbv (1-h average)) are often observed there. We analyzed the relationship between the occurrence of high Ox concentrations in the north Kanto and meteorological conditions. By combining the regional wind pattern and the presence of the inversion layer in the atmospheric boundary layer, we identified five distinct meteorological patterns. High Ox concentrations in the north Kanto area were associated with a southerly extended sea breeze accompanied by a subsidence inversion layer. We inferred that the transport of Ox from the southern urban area by southerly winds and restricted dispersion below the inversion layer can lead to high Ox concentrations in the north Kanto area. This meteorological condition is associated with the presence of a high pressure system centered in the southeastern or eastern sector offshore of the Kanto area. Thus, Ox concentrations in the north Kanto area, where emissions of precursors are relatively low, can easily increase to very high levels under favorable meteorological conditions. 相似文献
92.
Murata K Wakabayashi Y Sakamoto K Tanaka T Takeuchi Y Mori Y Okamura H 《The Journal of reproduction and development》2011,57(2):197-202
Exposure of females to the male pheromone induces pulsatile release of gonadotropin-releasing hormone (GnRH) in goats. Recently, kisspeptin neurons in the arcuate nucleus (ARC) have been suggested to represent the proximate source of the GnRH pulse generator. In this study, we examined the effects of the pheromone on multiple-unit activity (MUA) in female goats fitted with recording electrodes aimed at the ARC kisspeptin neurons. In all eight goats, periodic bursts in MUA (MUA volleys), which were considered to be electrophysiological manifestations of the GnRH pulse generator, were observed. The mean intervolley interval (T) during the control period was calculated in each goat that was then exposed to the male pheromone for 1 sec at timings of 1/4 T, 1/2 T or 3/4 T after one regularly occurring MUA volley. An instantaneous rise in MUA was observed immediately after the exposure regardless of timing. Exposure at a timing of 3/4 T resulted in an MUA volley within 60 sec following the instantaneous rise in all goats. In contrast, an MUA volley was induced in only 2 goats by exposure at 1/2 T, while exposure at 1/4 T failed to induce an MUA volley in any goats. These results suggest that transmission of the pheromone signal to the ARC, represented by an instantaneous rise, activates the GnRH pulse generator. Moreover, the timing-dependent pheromone action in inducing an MUA volley indicates that the GnRH pulse generator has a refractory period for the pheromone signal after the burst. 相似文献
93.
A Double‐blind,Placebo‐controlled,Multicenter, Prospective,Randomized Study of Beraprost Sodium Treatment for Cats with Chronic Kidney Disease 下载免费PDF全文
M. Takenaka A. Iio R. Sato T. Sakamoto H. Kurumatani the KT‐ Clinical Study Group 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2018,32(1):236-248
Background
Chronic kidney disease (CKD) is a common progressive and irreversible disease in cats. The efficacy and safety of beraprost sodium (BPS) in cats with CKD have not been evaluated.Hypothesis/Objectives
To evaluate the efficacy and safety of BPS in the treatment of cats with CKD, as compared to placebo.Animals
Seventy‐four client‐owned cats with naturally occurring CKD.Methods
Double‐blind, placebo‐controlled, multicenter, prospective, randomized trial. The cats received BPS (55 μg/cat) or a placebo PO q12 h for 180 days. The primary endpoint was prospectively defined as a change in the serum creatinine (sCr), serum phosphorus‐to‐calcium ratio or urine specific gravity (USG).Results
The sCr increased significantly (P = 0.0030) in the placebo group (mean ± SD: 2.8 ± 0.7 to 3.2 ± 1.3 mg/dL) but not in the BPS group (2.4 ± 0.7 to 2.5 ± 0.7 mg/dL). The difference between the groups at day 180 was significant (0.8 mg/dL, 95% CI: 0.2 to 1.3 mg/dL, P = 0.0071). The serum phosphorus‐to‐calcium ratio was significantly (P = 0.0037) increased in the placebo group (0.46 ± 0.10 to 0.52 ± 0.21 mg/dL) but not in the BPS group (0.50 ± 0.08 to 0.51 ± 0.11 mg/dL). There was no significant change in the USG in either group. An adverse event judged as being treatment‐related included vomiting that occurred in 1 case in the placebo group. No clinically relevant change was observed in the CBC and other blood chemistry tests.Conclusions and Clinical Importance
Beraprost sodium treatment was well tolerated and safe in cats with CKD. BPS inhibited the reduction in renal filtration function as measured by sCr increase. 相似文献94.
Marcus Vinicius Freire Andrade Isabel Kimiko Sakamoto Aline Gomes de Oliveira Paranhos Edson Luiz Silva Maria Bernadete Amâncio Varesche 《Water, air, and soil pollution》2017,228(4):165
Effects of ethanol and nitrate on linear alkyl benzene sulfonate (LAS) degradation were investigated using central composite design. At experimental design, removal of 99.9% was observed in batch reactors (1 L) with 9.8 to 41.2 mg L?1 of LAS. The batch reactors were kept under agitation at 120 rpm and 30 °C. Ethanol (co-substrate) and nitrate (electron acceptor) were statistically significant factors (p?<?0.05) in surfactant removal. Optimal values were 97.5 and 88 mg L?1 for ethanol and nitrate, respectively. LAS removal was kinetically investigated by varying surfactant concentration while using optimal values. Batch I (27 mg L?1 LAS) exhibited greater degradation rate (KLAS) (0.054 h?1) in the presence of ethanol and nitrate. Nonetheless, in Batch II (60 mg L?1 LAS), the KLAS values decreased in those reactors probably due to inhibition by excess substrate for same concentrations of nitrate and ethanol added in reactors. As LAS concentration increased, the dominance of bacterial populations also increased, whereas diversity index decreased from 2.8 (inoculum) to 2.4 and 2.5 for reactors with both added nitrate and ethanol and those with only added ethanol, respectively. Probably, a selection of microbial populations occurred in relation to LAS concentration. The nitrate and ethanol, at able concentration, made it possible the induction of denitrifying microrganisms foward to LAS removal. 相似文献
95.
96.
Yasuda K Hashikawa S Sakamoto H Tomita Y Shibata S Fukata T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2007,69(2):205-208
To evaluate the effects of a new synbiotic consisting of Lactobacillus casei subsp. casei (Lcc) and dextran (Dex) on milk production, a total of 58 Holstein dairy cows, which became pregnant and gave birth to calves at regular intervals and lactated steadily and continuously, were selected. The study had a completely randomized design, and the animals were divided into two groups. Group A was fed with a basic diet only, and Group B was fed with a basic diet supplemented with the synbiotic consisting of freeze-dried Lcc and mixed feed containing Dex for one year from August 2004. After supplementation with the synbiotic, milk yields and components of Group B were compared with those of Group A in the August, December of 2004, April and August of 2005. Milk yields of Group B were greater than those of Group A. There were significant differences (p<0.01 or 0.05) between these groups for all values. Furthermore, total amounts of fat, protein and solid non-fat in Group B significantly increased in comparison with those of Group A. In addition, the somatic cell counts of Group A significantly increased in August of 2004 and 2005 in comparison with those of Group B. Thus, the new synbiotic consisting of Lcc and Dex can increase the milk production of Holstein dairy cows throughout the year. 相似文献
97.
Fujiki M Shineha J Yamanokuchi K Misumi K Sakamoto H 《American journal of veterinary research》2007,68(8):827-833
OBJECTIVE: To investigate the effects of polysulfated glycosaminoglycan (PSGAG) treatment on serum cartilage oligomeric matrix protein (COMP) concentration, matrix metal-loproteinase-2 (MMP-2) and -9 (MMP-9) activities, C-reactive protein (CRP) concentration, and lameness scores in dogs with osteoarthritis. ANIMALS: 16 dogs with osteoarthritis and 5 clinically normal dogs. PROCEDURES: Dogs with osteoarthritis had a history of chronic lameness, and osteophytes were observed on radiographic evaluation of the affected joint. Polysulfated glycosaminoglycan was administered IM twice a week for a total of 8 treatments to all dogs with osteoarthritis and to clinically normal control dogs. RESULTS: Lameness scores after PSGAG treatment in osteoarthritic dogs improved in 12 of the 16 dogs. Serum COMP concentrations in osteoarthritic dogs were significantly higher than in control dogs before treatment. Lameness scores in osteoarthritic dogs decreased significantly after treatment, compared with before treatment. Lameness scores of 9 dogs with hind limb lameness improved significantly after treatment; these dogs had corresponding decreases in serum COMP concentrations. After treatment, serum COMP concentrations and lameness scores of 7 dogs with forelimb lameness remained high and were significantly higher than those of dogs with hind limb lameness. Serum MMP-9 activities of dogs with forelimb lameness were significantly higher than in dogs with hind limb lameness after treatment. CONCLUSIONS AND CLINICAL RELEVANCE: IM administration of PSGAG inhibited COMP degradation in dogs with osteoarthritis. Results indicate that decreases in serum COMP concentrations might be related to improvement in lameness after PSGAG treatment. 相似文献
98.
Kimberly Crawford Kelly Lager Laura Miller Tanja Opriessnig Priscilla Gerber Richard Hesse 《Veterinary research》2015,46(1)
Clinical disease associated with porcine epidemic diarrhea virus (PEDV) infection in naïve pigs is well chronicled; however, information on endemic PEDV infection is limited. To characterize chronic PEDV infection, the duration of infectious virus shedding and development of protective immunity was determined. On Day 0 (D0), a growing pig was challenged with PEDV and 13 contacts were commingled. On D7, 9 contact pigs (principal virus group (PG)), were selected, moved to a separate room and commingled with one sentinel pig (S1). This process was repeated weekly with S2, S3 and S4. The PG was PEDV-positive by PCR from D3-11, with some pigs intermittently positive to D42. Pigs S1 and S2 were PEDV-positive within 24 hours of commingling. Antibodies were detected in all PG by D21 and by 7 days post-contact in S1 and S2. Pigs S3 and S4 were PCR and antibody negative following commingling. To evaluate protective immunity, 5 naïve pigs (N) and the PG were challenged (N/C, PG/C) with homologous virus on D49. All N/C pigs were PEDV PCR-positive by D52 with detection out to D62 in 3/5 N/C pigs. All PG/C pigs were PEDV PCR-negative post-challenge. By D63, all N/C seroconverted. Although PEDV RNA was demonstrated in pigs after primary infection until D42, infectious PEDV capable of horizontal transmission to naïve pigs was only shed 14–16 days after infection to age-matched pigs. Homologous re-challenge 49 days post initial PEDV exposure did not result in re-infection of the pigs. This demonstrates potential for an effective PEDV vaccine. 相似文献
99.
Akihiko Kotera Khang Duy Nguyen Toshihiro Sakamoto Toshichika Iizumi Masayuki Yokozawa 《Paddy and Water Environment》2014,12(3):343-354
We developed a crop scheduling model for rice cultivation in the Vietnam Mekong Delta (VMD), focusing on the adaptive behavior of crop planning to various water resource constraints. In addition, we also examined the effects of environmental change on rice cultivation in the last decade. In the VMD, multiple rice cropping is practiced under a variety of adverse water conditions, including flooding, salinity intrusion, and irregular monsoon rains. These environmental changes influence the durations of growing seasons and the number of crops per year, resulting in changes in productivity. To validate the performance of the model, we compared model estimates for the heading date and changes in leaf area index at nine sites with estimates of these parameters derived from MODIS satellite time series data for the period 2002–2006. The root mean square errors of heading date between the modeled and satellite data in the upper, middle, and coastal regions of the delta were 17.6, 11.2, and 13.0 days, respectively. Based on the model, we examined case studies to assess the changes in cropping cycles and crop failures in the VMD due to extreme flooding in 2000 and salinity intrusion in 2004 by applying evaluation indices defined by available period for cultivation (APC) and safe margin for cropping (SMC) which is defined as the marginal time between APC and the period required for cultivation. Findings of case studies suggested that a small difference in the SMC of the cropping pattern is critical to the stability and productive capacity of the rice crop. 相似文献
100.
Rie Matsumoto Natsumi Umezawa Masafumi Karaushi Shin-Ichi Yonemochi Kazuhiko Sakamoto 《Water, air, and soil pollution》2006,173(1-4):355-371
To understand the effect of the NH3 emissions from vehicles, the NH4 + bulk deposition and concentrations of gaseous NH3 and particulate NH4 + were measured at two sites in Saitama prefecture, Japan, one at the roadside of an arterial road (Kounosu), and the other in an agricultural area (Kisai). We observed that the NH4 + bulk deposition and NH3 concentration were significantly increased in Kounosu; the effect of NH3 emissions from vehicles was confirmed. NOx was a primary pollutant mainly emitted by vehicle exhaust in the vicinity of arterial roads, and the relationship between NO x and sum of gaseous NH3 and particulate NH4 + (T-NH4 +) was examined. The [T-NH4 +/NO x ] ratios in Kounosu ranged from 0.08 to 0.23 (average 0.15), and in Kisai they ranged from 0.16 to 0.67 (average 0.39). In Kounosu, the effect of vehicle exhaust was great, but seasonal variation was small. The contribution ratio of NH3 from vehicle emissions increased at low temperatures, while that from the non-vehicle emissions increased at high temperatures. 相似文献