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91.
Eighty-five thoroughbred racehorses with various types of fracture were subjected to arthroscopic surgery (44 horses) or internal fixation (41 horses) under sevoflurane anesthesia. The mean end-tidal sevoflurane concentration during anesthesia ranged from 2.5 to 2.8%. PaCO2 was maintained between 50 and 65 mmHg by controlled ventilation. The mean arterial blood pressure was maintained above 65 mmHg by infusion of dobutamine and fluids, however, heart rate significantly increased with time. Recovery from anesthesia was calm and smooth in almost all cases. No apparent complication was observed during and after anesthesia in all cases. Therefore, sevoflurane anesthesia is considered to be safe and useful for orthopedic surgery in racehorses.  相似文献   
92.
Vibrational properties of heat-treated green wood   总被引:2,自引:0,他引:2  
To investigate the influence of water on heat treatment, green wood was heat-treated. Sitka spruce (Picea sitchensis Carr.) with about 60% moisture content (MC) was used. Young's modulus and loss tangent were measured by the free-free flexural vibration test. The specimens were heated in nitrogen at 160°C for 0.5h. The results were as follows. (1) Recognizing that the effects of heat treatment are mild and that the same specimens cannot be used for both heat treatment and as controls, it was necessary to investigate the effects of the heat treatment based on the variations of properties in the whole of the test lumber. (2) Young's modulus increased and the loss tangent decreased due to heat treatment. When the vibrational properties were measured at various MCs, the MCs at the maximum value of Young's modulus and the minimum value of the loss tangent were lower in heat-treated specimens than in controls. The effects of heat treatment in green wood were similar to those in air-dried wood. (3) The loss tangents of heat-treated specimens were smaller than those of controls at about 0% MC but were larger than those of controls at about 10% MC. We thought that this resulted from the decreased MC at the minimum loss tangent after the heat treatment mentioned above. (4) The properties measured at several MCs were more useful than those at only one moisture content for investigating the effects of heat treatment.This study was presented in part at the 46th annual meeting of the Japan Wood Research Society, Kumamoto, April 3–5, 1996; and at the 47th annual meeting of the Japan Wood Research Society, Kochi, April 3–5, 1997  相似文献   
93.
We examined the applicability of end-notched flexure (ENF) tests for measuring the mode II fracture toughness of wood. Western hemlock (Tsuga heterophylla Sarg.) was used for the specimens. The fracture toughness at the beginning of crack propagationG IIc and that during crack propagationG IIR were calculated from the loadloading point compliance and load-crack shear displacement (CSD) relations. The obtained results were compared with each other, and the validity of measurement methods were examined. The results are summarized as follows: (1) The value ofG IIc increased with the increase in initial crack length. When measuringG IIc by ENF tests, we should be aware of the dependence ofG IIc on the initial crack length. (2) The value ofG IIR initially increased with the crack length, and it reached a constant value. (3) Measurement of the CSD is recommended when obtainingG IIR because the crack length, which has a great influence on theG IIR calculation, is implicitly included in the CSD. (4) We found that the crack length during its propagation should be evaluated by the final crack length.  相似文献   
94.
MicroRNAs (miRNAs) play a role in the pathogenesis of certain diseases and may serve as biomarkers. Here, we present the first analysis of miRNA expression in the kidneys of healthy cats and dogs. Kidneys were divided into renal cortex (CO) and medulla (MD), and RNA sequence analysis was performed using the mouse genome as a reference. A total of 277, 276, 295, and 297 miRNAs were detected in cat CO, cat MD, dog CO, and dog MD, respectively. By comparing the expression ratio of CO to MD, we identified highly expressed miRNAs in each tissue as follows: 41 miRNAs including miR-192-5p in cat CO; 45 miRNAs including miR-323-3p in dog CO; 78 miRNAs including miR-20a-5p in cat MD; and 11 miRNAs including miR-132-5p in dog MD. Further, the target mRNAs of these miRNAs were identified. These data provide veterinary medicine critical information regarding renal miRNA expression.  相似文献   
95.
We recently developed a Landrace line that is resistant to mycoplasmal pneumonia of swine (MPS) infection by genetic selection for five generations, and we reported that the immunophenotype of this line is different from that of the non‐selected line in terms of changes in peripheral blood leukocyte population after MPS vaccination. This study followed up previous findings demonstrating changes in soluble factors in blood, namely, hormones, Mycoplasma hyopneumoniae‐specific immunoglobulin G (IgG), and cytokines. These two lines were injected with MPS vaccine on days ?7 and 0 after blood sampling on those days, and blood samples were collected on days ?14, ?7, 0, 2, 7 and 14. We found changes in the levels of many hormones and cytokines in both lines. However, we found that only growth hormone (GH) and interferon (IFN)‐γ levels were statistically different between these two lines. GH concentration was reduced (day 0) and IFN‐γ concentration was increased (day 14) in the MPS‐selected line compared with the non‐selected line, despite unchanged IFN‐γ messenger RNA expression in blood cells. Although detailed mechanisms underlying these phenotypes remain unsolved, these traits would be useful to improve MPS resistance in pig production and provide an insight into MPS infection.  相似文献   
96.
Utiyama  M.  Fukuyama  T.  Yamagata  S.  Ohta  S.  Izumi  K.  Harimaya  T.  Fujiyoshi  Y.  Yamada  T.  Inage  M. 《Water, air, and soil pollution》2001,130(1-4):325-330
Water, Air, &; Soil Pollution - Removal of sulfur dioxide through the absorption into cloud droplets is the initial stage of acid rain formation. We studied this process by forming an artificial...  相似文献   
97.
The genus Aegilops L. comprises 22 annual wild species that are closely related to wheat (Hammer in Kulturpflanze 28: 33–180, 1980). Aegilops neglecta Req. ex Bertol. is a member of the Aegilops section of this genus and is distributed from Morocco and Spain in the west to Transcaucasia and western Iran in the east. This species includes tetraploid (2n = 28, genome UUMM) and hexaploid forms (2n = 42, UUMMNN). However, the geographical distributions of the two cytological forms remain unclear. Clarifying the distribution of the two cytological forms is essential for a better understanding of the diffusion of Ae. neglecta and its tetraploid and hexaploid forms. In the present study, chromosome numbers were determined for accessions of Ae. neglecta from a total of 137 populations, located in the western area of the species distribution from the Aegean Islands to Morocco. Taken together with previous studies, the present data reveal a difference in the geographical distribution of tetraploid and hexaploid forms: tetraploid form is distributed in the eastern part of the species area and hexaploid form predominantly occurs in the western part with their border on the western margin of the Aegean Sea. Near the border, tetraploid and mixed populations are sporadically found among hexaploid populations in the Balkan and Peloponnesus Peninsulas, while a few hexaploid and mixed populations are found among tetraploid populations in the East Aegean Islands and West Anatolia.  相似文献   
98.
It is essential to analyze chemical properties including the amount of various materials and the soil colloid characteristics in forest soils to forecast wood production and the distribution of and variations in the environmental functions of forest soils, such as conservation of stream water and carbon sequestration. Approximately 70% of the forest soils in Japan consists of Brown Forest Soils (BFS), which are considered to be typical zonal soils under the humid-temperate and warm-temperate regime of Japan. BFS were subclassifled into several groups according to the soil moisture environment along the slope and morphological properties. However, even the same type of soil may display different properties depending on the climatic conditions, parent materials and vegetation types. In the present study, the variations in the carbon content, nitrogen content, cation exchange capacity and some properties depending on the parent materials, were clarified by using 34 sola of BFS, and 3 sola of black soils (BLS) for comparison, which were distributed in the submontane zone of the Kanto and Chubu districts in central Japan under the same climatic conditions. We observed differences in the pH, cation exchange capacity, base saturation and clay content among BFS samples derived from various parent materials. The BFS derived from volcanic ash contained obviously larger amounts of carbon and nitrogen than the BFS derived from other parent materials. However, the BFS derived from volcanic ash differed from the BLS derived from volcanic ash in the vertical distribution pattern of carbon and nitrogen. Thus, even in the submontane zone of the Kanto and Chubu districts, the chemical properties of BFS varied considerably with the parent materials. It was concluded that the classification of BFS by the parent materials was useful for evaluating the ability of the BFS, that cover 70% of the forests in Japan, to store various materials.  相似文献   
99.
Metabolism of polychlorinated dibenzo-p-dioxins (PCDDs) by monooxygenase systems dependent on 12 forms of human cytochrome P450 (CYP) was examined with the recombinant yeast microsomes containing each of the human CYP. The metabolites of PCDDs were analyzed by HPLC and GC-MS. Remarkable metabolism by the multiple CYP forms was observed toward dibenzo-p-dioxin (DD) and mono-, di-, and trichloroDDs. The metabolism contained multiple reactions such as hydroxylation at an unsubstituted position, hydroxylation with migration of a chloride substituent, and hydroxylation with elimination of a chloride substituent. Although major CYPs in human liver such as CYP2C8, CYP2C9, and CYP3A4 showed no significant metabolism toward the PCDDs, CYP1A1 and CYP1A2 showed high catalytic activity toward DD and mono-, di-, and trichloroDDs. The kinetic parameters K(m)(app) and V(max) of the CYP1A1-dependent 8-hydroxylation activity of 2,3,7-trichloro-DD (2,3,7-triCDD) were estimated to be 0.30 microM and 51 (mol/min/mol of P450), respectively, suggesting that 2,3,7-triCDD was a good substrate for CYP1A1. However, none of the CYPs showed any detectable activity [<0.01 mol/min/mol of P450)] toward 2,3,7,8-tetraCDD. Substrate-induced absorption spectrum and inhibition studies indicated that CYP1A1 could bind 2,3,7,8-tetraCDD with considerably high affinity. It was strongly suggested that the long half-life (7.1 years) of 2,3,7,8-tetraCDD in humans was due to an extremely low activity of CYPs toward 2,3,7,8-tetraCDD in addition to its chemical stability.  相似文献   
100.

Routine monitoring for subclinical infection is one of the key mastitis control approaches. However, the accuracy of the most commonly used screening tests has not yet been established. The aim of the present study was therefore to evaluate the accuracy of three screening tests, namely California mastitis test (CMT), white side test (WST), and surf field mastitis test (SFMT) for the screening of subclinical caprine mastitis. A cross-sectional study based on 484 randomly collected milk (242 goats) samples from three districts of Bangladesh was conducted for the screening of subclinical mastitis by the aforementioned tests. The Bayesian latent class model was implemented in WinBUGS to estimate the tests’ characteristics and true prevalence of subclinical mastitis. The Bayesian posterior estimates of sensitivities with a 95% credible intervals (CrIs) were 98.60% (95.18–99.95%), 98.28% (94.56–99.92%), and 89.98% (83.39–95.03%), and specificities with 95% CrIs were 99.19% (98.11–99.96%), 99.27% (97.34–99.98%), and 99.28% (97.35–99.98%), respectively for CMT, WST, and SFMT. The true prevalence of subclinical caprine mastitis was estimated to be 43.49% (95% CrI 37.46–48.98%). The positive predictive values (PPV) of the three tests were similar. The serial and parallel interpretation of any test pairs increased the PPV and negative predictive value respectively close to 100%. Based on the simplicity, cost and performance as well WST and SFMT simultaneously could be recommended for the screening of caprine subclinical mastitis in Bangladesh.

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