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191.
The purpose of this study was to understand the mechanisms of persistent infection with Bartonella henselae in cats. Blood samples were collected from three naturally infected cats for 24 months. These cats were confirmed to be persistently infected with B. henselae by serological and bacteriological examination. Relapsing bacteremia was found in all three cats with intervals of 3-19 months. Following the peaks of bacteremia, increases of specific antibody titer were observed in these cats. To examine the genetic differences among the isolates derived from the first and following bacteremia, the genome DNA patterns of the restriction enzyme fragment length polymorphism (RFLP) of the isolates were examined by pulsed field gel electrophoresis. The isolates derived from the first bacteremia showed an identical RFLP pattern in each of the three cats. The isolates derived from the following peaks, however, showed 1-3 of different RFLP patterns in these cats. Furthermore, the isolates showing different RFLP patterns from those of the first bacteremia were also detected at the following bacteremic peaks in all three cats examined. The 16S ribosomal RNA (rRNA) gene type of all isolates was found to be 16S rRNA type I. The emergence of genetically distinct organisms at various peaks of bacteremia may contribute to the establishment of persistent infection in the naturally infected cats.  相似文献   
192.
Most methods for determining cardiac output (CO) have limited application in clinical practice due to the invasive techniques required. This study compared the thermodilution technique (TDCO) with three noninvasive methods for determining CO in anesthetized dogs: transthoracic bioimpedance (BICO), partial CO2 rebreathing (NICO), and transesophageal echocardiography (TEECO). TDCO was compared to BICO, NICO, and TEECO in six adult sevoflurane anesthetized beagle dogs (9.1–13.0 kg). All dogs were administered midazolam [0.3 mg kg?1, intravenously (IV)] and butorphanol (0.1 mg kg?1 IV), followed by ketamine (5.0 mg kg–1 IV) and sevoflurane in nitrous oxide (1 L minute–1) and oxygen (1 L minute–1) and mechanically ventilated. Dogs were maintained at 2.2% end‐tidal sevoflurane (ETsev) concentration for instrumentation and baseline measurements. Low (5.0% ETsev), intermediate (3.3% ETsev), and high cardiac output values were achieved by varying the end‐tidal sevoflurane concentration and the administration of dobutamine (3–10 g kg–1 minute–1 and 2.2% ETsev). A minimum of thirty data sets was obtained for each comparison. The correlation coefficients when compared to TDCO were 0.684 for BICO (p < 0.0001), 0.883 for NICO (p < 0.0001), and 0.991 for TEECO (p < 0.0001). Cardiac output values ranged 50–444 mL kg–1 minute–1 for TDCO, 100–253 mL kg–1 minute–1 for BICO, 64–214 mL kg–1 minute–1 for NICO, and 52–401 mL kg–1 minute–1 for TEECO. The differences when compared to TDCO ranged – 62–235 mL kg?1minute?1 for BICO, 18–220 mL kg?1 minute?1 for NICO, and – 35–32 mL kg–1 minute–1 for TEECO. Differences were maximum at the highest CO in BICO and NICO. In conclusion, this study demonstrated that BICO and NICO underestimate CO in sevoflurane anesthetized dogs. TEECO is a viable noninvasive method for determining CO in sevoflurane anesthetized dogs.  相似文献   
193.
The anesthetic and cardiovascular effects of a combination of continuous intravenous infusion using a mixture of 100 g/L guaifenesin-4 g/L ketamine-5 mg/L medetomidine (0.25 ml/kg/hr) and oxygen-sevoflurane (OS) anesthesia (GKM-OS anesthesia) in horses were evaluated. The right carotid artery of each of 12 horses was raised surgically into a subcutaneous position under GKM-OS anesthesia (n=6) or OS anesthesia (n=6). The end-tidal concentration of sevoflurane (EtSEV) required to maintain surgical anesthesia was around 1.5% in GKM-OS and 3.0% in OS anesthesia. Mean arterial blood pressure (MABP) was maintained at around 80 mmHg under GKM-OS anesthesia, while infusion of dobutamine (0.39+/-0.10 microg/kg/min) was necessary to maintain MABP at 60 mmHg under OS anesthesia. The horses were able to stand at 36+/-26 min after cessation of GKM-OS anesthesia and at 48+/-19 minutes after OS anesthesia. The cardiovascular effects were evaluated in 12 horses anesthetized with GKM-OS anesthesia using 1.5% of EtSEV (n=6) or OS anesthesia using 3.0% of EtSEV (n=6). During GKM-OS anesthesia, cardiac output and peripheral vascular resistance was maintained at about 70% of the baseline value before anesthesia, and MABP was maintained over 70 mmHg. During OS anesthesia, infusion of dobutamine (0.59+/-0.24 microg/kg/min) was necessary to maintain MABP at 70 mmHg. Infusion of dobutamine enabled to maintaine cardiac output at about 80% of the baseline value; however, it induced the development of severe tachycardia in a horse anesthetized with sevoflurane. GKM-OS anesthesia may be useful for prolonged equine surgery because of its minimal cardiovascular effect and good recovery.  相似文献   
194.
Neutron activation analysis and gamma-ray spectroscopy were used to determine the quantity of potassium and sodium in an ash sample of Tabebuia sp bombarded with thermal neutrons. These techniques, widely applied in nuclear physics, can be used in the context of wood science as an alternative for the usual physical chemistry methods applied in this area. The quantity of K and Na in an 8.60±0.10 mg of ash was determined as being 1.3±0.3 mg and 11.0±1.8 μg, respectively. The ratio of Tabebuia sp converted into ash was also determined as 0.758±0.004%.  相似文献   
195.
This study aimed to develop an in vitro model for the analysis of the bovine endometrium. Immunofluorescent staining revealed that the hetero‐spheroids and the cultured explants showed almost similar structure in the localization of bovine endometrial epithelial cells and endometrial stromal cells, except the glandular‐like structure of the epithelial cells inside the explants. Gelatin zymography revealed that the hetero‐spheroids did not express matrix metalloproteinases (MMPs) after 4 days of culture, but strong MMP expressions were observed in the cultured explants until 7 days of culture. Additionally, expression of progesterone receptor (PR), estrogen receptor alpha (ERα), type I interferon receptor 1 (IFNAR1) and 2 (IFNAR2) messenger RNA was observed both in the homo‐ and hetero‐spheroids. The expression of oxytocin receptor (OTR) mRNA in E2 and E2+P4 (1,3,5(10)‐Estratrien‐3, 17β‐diol + 4‐Pregnen‐3, 20‐dinone) treated groups were significantly (P < 0.05) higher than that of the control group of spheroids. In case of cultured explants, the expression of PR and OTR mRNA were significantly (P < 0.05) higher in E2 treated groups compared to the control groups. Hepatocyte growth factor (HGF) mRNA expression was also higher in P4 treated groups at 10 days in culture (P < 0.05). In a nutshell, the in vitro model developed in this study for the analysis of the endometrium may provide a new platform for extensive research on bovine endometrial function.  相似文献   
196.
The anesthetic and cardiopulmonary effects of midazolam, ketamine and medetomidine for total intravenous anesthesia (MKM-TIVA) were evaluated in 14 horses. Horses were administered medetomidine 5 microg/kg intravenously as pre-anesthetic medication and anesthetized with an intravenous injection of ketamine 2.5 mg/kg and midazolam 0.04 mg/kg followed by the infusion of MKM-drug combination (midazolam 0.8 mg/ml-ketamine 40 mg/ml-medetomidine 0.1 mg/ml). Nine stallions (3 thoroughbred and 6 draft horses) were castrated during infusion of MKM-drug combination. The average duration of anesthesia was 38 +/- 8 min and infusion rate of MKM-drug combination was 0.091 +/- 0.021 ml/kg/hr. Time to standing after discontinuing MKM-TIVA was 33 +/- 13 min. The quality of recovery from anesthesia was satisfactory in 3 horses and good in 6 horses. An additional 5 healthy thoroughbred horses were anesthetized with MKM- TIVA in order to assess cardiopulmonary effects. These 5 horses were anesthetized for 60 min and administered MKM-drug combination at 0.1 ml/kg/hr. Cardiac output and cardiac index decreased to 70-80%, stroke volume increased to 110% and systemic vascular resistance increased to 130% of baseline value. The partial pressure of arterial blood carbon dioxide was maintained at approximately 50 mmHg while the arterial partial pressure of oxygen pressure decreased to 50-60 mmHg. MKM-TIVA provides clinically acceptable general anesthesia with mild cardiopulmonary depression in horses. Inspired air should be supplemented with oxygen to prevent hypoxemia during MKM-TIVA.  相似文献   
197.
Botrytis cinerea field isolates collected in Japan were screened for resistance to Qo inhibitor fungicides (QoIs). Of the 198 isolates screened, six grew well on a medium containing azoxystrobin, a QoI, when salicylhydroxamic acid, an alternative oxidase inhibitor, was present. The resistance mutation in the cytochrome b gene ( cytb ) was characterized. All QoI-resistant isolates had the same mutation (GGT to G C T) in cytb that led to the substitution of glycine by alanine at position 143 of cytochrome b , which is known to confer QoI resistance in plant pathogens. To detect this mutation, a hybridization probe assay based on real-time PCR amplification and melting curve analysis was developed. Using DNA samples prepared from aubergines coinfected with QoI-resistant and QoI-sensitive B. cinerea isolates, two similar peak profiles with their corresponding melting temperatures were obtained. This result suggests that QoI-resistant and QoI-sensitive isolates may compete equally in terms of pathogenicity, and the assay may be used to assess the population ratio of mutant and wild-type isolates. However, the hybridization probe did not anneal to PCR products derived from the DNA samples of some QoI-sensitive isolates. Structural analysis of cytb revealed that B. cinerea field isolates could be classified into two groups: one with three introns and the other with an additional intron (Bcbi-143/144 intron) inserted between the 143rd and 144th codons. All 88 isolates possessing the Bcbi-143/144 intron were azoxystrobin-sensitive, suggesting that the QoI-resistant mutation at codon 143 in cytb prevents self-splicing of the Bcbi-143/144 intron, as proposed in some other plant pathogens.  相似文献   
198.
Four triterpenoid compounds hederacolchiside E (1), hederasaponin B (2), raddeanoside 20 (3) and raddeanoside 21 (4) were isolated from ethanol extracts of rhizome of Anemone raddeana Regel. The effects of these triterpenoids on superoxide generation, tyrosyl phosphorylation of proteins and translocation of cytosolic compounds, such as p47phox, p67phox and Rac to the cell membrane in human neutrophils was investigated. The superoxide generation induced by N-formyl-methionyl-leucyl-phenylalanine (fMLP) was slightly suppressed by hederasaponin B, raddeanoside 20 and raddeanoside 21 in a concentration dependent manner. The superoxide generation induced by arachidonic acid (AA) was suppressed by hederasaponin B and raddeanoside 21 significantly. fMLP- and AA-induced tyrosyl phosphorylation and translocation of the cytosolic proteins: p47phox, p67phox, and Rac to the cell membrane were suppressed in parallel with the suppression of stimulus-induced superoxide generation.  相似文献   
199.
The adsorption properties of wood carbonized at various temperatures were investigated using a mixed gas containing toluene and α-pinene. Hinoki (Chamaecyparis obtusa) samples carbonized at 500°–1100°C were exposed to gas mixtures of toluene and α-pinene at 20°C. The samples carbonized at 500°–700°C only adsorbed toluene, whereas those carbonized at 800°–1100°C adsorbed both toluene and α-pinene. Analysis of the surface structure of the carbonized wood by nitrogen adsorption at liquid nitrogen temperature indicated that the sample carbonized at 700°C had micropores mainly 0.6 nm in diameter and few mesopores, whereas the samples carbonized at 900°C and 1100°C had mesopores and micropores larger than 0.8 nm in diameter. With the sample carbonized at 700°C, the flat-shaped toluene molecules could probably penetrate into the narrower pores, 0.8 nm in diameter, whereas the bulky globular-shaped α-pinene molecules could not. Carbonization at temperatures higher than 900°C probably enlarged the pore size and thereby reduced the selectivity of adsorption. The results revealed that wood carbonized below activation temperature has a unique flat-pore structure that seems to work as a kind of molecular sieving carbon, successfully removing only the harmful volatile organic compound (VOC), toluene, and leaving behind a pleasant aroma of α-pinene in the atmosphere.  相似文献   
200.
In several autogamous and vegetatively propagated crops, DNA markers have been used for cultivar identification. However, allogamous crops such as bunching onion (Allium fistulosum L.) are recalcitrant to marker-aided cultivar identification, as well as hybrid seed purity tests, due to the high degree of genetic heterogeneity within each cultivar. To aid cultivar identification and ensure its accuracy in bunching onion, we proposed the “SSR-tagged breeding” scheme in our previous study. The feasibility of this scheme was investigated here using a landrace of bunching onion with two populations tagged with two or four selected SSR markers. Compared with a control population, no significant differences were detected in the agronomic traits of the SSR-tagged populations. The targeted SSR loci were genetically uniform within each population whereas other loci maintained high heterogeneity. These results demonstrate that the SSR-tagged breeding scheme, even with a very small number of markers, is efficient for the identification of newly bred cultivars, and consequently for F1 purity tests, in allogamous crops in which inbreeding depression is as severe as in bunching onion.  相似文献   
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