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21.
To evaluate the effects of compression atelectasis on the composition of pulmonary secretions in anesthetized horses, cytological and biochemical examinations were performed on bronchoalveolar lavage (BAL) fluids obtained from both dependent and independent lung regions. Six horses were anesthetized with isoflurane and oxygen for 120 min, and were positioned in right lateral recumbency. Percentage of neutrophils and total protein concentration in BAL fluids significantly increased at the end of anesthesia, and total phosphorous concentration significantly decreased at 72 hr after anesthesia in dependent lung. Such changes were not observed within 168 hr after anesthesia. These findings suggest that the effects of compression atelectasis on the composition of pulmonary secretions may be eliminated within 168 hr after anesthesia.  相似文献   
22.
ABSTRACT It has been speculated that the N-terminal half of the readthrough domain (RTD) encoded by open reading frame 5 of Soybean dwarf virus (SbDV) is related to the vector specificity. To further investigate this hypothesis, transmissibility via aphids was tested on 17 SbDV isolates and comparisons of the deduced amino acid sequences of the coat protein (CP) and other proteins encoded by the RTD were made between these isolates. Isolates were distinguished into four strains: YS, causing yellowing in soybean and transmittable by Aulacorthum solani; DS, causing dwarfing and transmittable by A. solani; YP, causing yellowing and transmittable by Acyrthosiphon pisum; and DP, causing dwarfing and transmittable by A. pisum. Phylogenetic analysis showed that the trees for the CP and the C-terminal half of the RTD sequences contained clusters of isolates of the same symptom type, whereas the tree for the N-terminal half of the RTD contained clusters of isolates of the same aphid vector type. These results agreed with our previous data of the complete nucleotide sequences of four SbDV isolates, and strongly indicated a close relationship between the N-terminal half of the RTD amino acid sequences and aphid transmission specificity of SbDV.  相似文献   
23.
The correlation between the serum hydroxyproline concentration and serum activity levels of TRAP and BALP was examined in 41 cows. The correlated coefficient (r) was 0.6391 for TRAP and 0.3147 for BALP, respectively. Judging from the significant correlation to the serum hydroxyproline concentration, serum TRAP activity is an index for bone metabolism in cows. Serum TRAP activity was therefore measured in 205 healthy cows (2-9 years old) in order to observe the changes in bone resorption with aging and milk production. TRAP levels differed slightly between group A (< or =4 yrs) and B (5 yrs< or =) at the same stage of lactation. The activity levels rose slightly at the height of lactation stage and during the dry stage.  相似文献   
24.
The direct effects of three steroid hormones (progesterone, estradiol-17beta and corticosterone) on the growth of Neospora caninum (N. caninum) tachyzoite were examined in Vero cells. Subsequently, ovariectomized BALB/c mice infected with N. caninum were treated with physiological concentrations of the steroid hormones for 1 or 2 weeks. These hormones had no direct effect on the parasite growth in vitro. In the infected mice, there was no significant difference in the parasite distribution and histopathological changes between the hormone-injected and control groups. No mice showed parasitemia at the time of autopsy. These results suggest that physiological levels of steroid hormones (progesterone, estradiol-17beta and corticosterone) do not reactivate N. caninum in mice.  相似文献   
25.
The protective activity of Mycoplasma hyopneumoniae inactivated vaccine prepared from sedimented whole cells and cell-free culture supernates was evaluated experimentally using hysterectomy-produced, colostrum-deprived pigs in which mycoplasmal pneumonia had been induced. The culture supernate vaccine containing less than 10(1) colour-changing units (CCU)/0.2 ml of M. hyopneumoniae significantly (P < 0.05) reduced the percentage of lung lesions compared to controls (3.2 +/- 3.9 vs. 12.2 +/- 2.2%), whereas the sedimented whole cells vaccine containing 10(10) CCU/0.2 ml of organisms provided variable protection (18.7 +/- 16.5 vs. 12.2 +/- 2.2%). Serum from the pigs vaccinated with culture supernate reacted with six protein bands of 97, 89, 65, 46, 42 and 41 kDa by immunoblot analysis. From these results, we conclude that vaccination with culture supernate of M. hyopneumoniae can provide protection against M. hyopneumoniae infection and that these antigens in the culture supernate may be closely related to the reduction of lung lesions.  相似文献   
26.
ABSTRACT:   Gnomefish Scombrops boops and Scombrops gilberti are commercially important fishes in Japan, but these species are often confused in the markets because of their morphological similarity. To identify these two species, we performed nucleotide sequencing and restriction fragment length polymorphism (RFLP) analysis on 16S ribosomal RNA (rRNA) gene and the control region in mitochondrial DNA. Five and 12 nucleotide substitutions were observed between species in the 777-bp 16S rRNA gene and 471-bp control region, respectively. Diagnostic restriction sites for discriminating between S. boops and S. gilberti were found in the 16S rRNA gene, but not in the control region. Polymerase chain reaction (PCR)–RFLP analysis using two enzymes, Eco NI and Mva I, clearly discriminated between S. boops and S. gilberti identified by meristic characters. The PCR–RFLP analysis identified most of the 168 Scombrops young caught in the coastal waters of the Izu and Miura peninsulas as S. boops , suggesting that S. gilberti juveniles are rare in this area.  相似文献   
27.
ABSTRACT:   Age and growth of alfonsino Beryx splendens (Lowe) were studied using counts of presumed daily incremental growth rings on the transverse section of otoliths of fish collected from the Kanto District, central Japan. Microstructural growth increments were observed from the core to the outermost margin of the broadest of approximately 50 branches formed on the surface of an otolith. Of 98 otoliths examined, 46 were readable. The number of increments and fish lengths ranged from 448 (218 mm fork length [FL]) to 3701 (411 mm FL). The ages of these fish were estimated to be 1 year, 2 months and 10 years, 2 months, respectively, assuming that an increment was formed daily. The von Bertalanffy growth equation combined for males and females was expressed as follows: L t  = 542 {1 −  exp  [−0.133( t  + 2.00)]}, where L t is fork length (mm) at yearly age t . The results of the present study were compared with those of other researchers who had studied alfonsino from central Japan.  相似文献   
28.
29.
Poxvirus infection in Nile crocodiles (Crocodylus niloticus)   总被引:1,自引:0,他引:1  
An outbreak was encountered of numerous yellowish cutaneous nodules in one- to two-year-old farmed Nile crocodiles (Crocodylus niloticus) in Kasaba Bay Crocodile Farm at Lake Tanganyika in Zambia during 1988. Out of 4000 crocodiles of different age groups, 300 yearlings were affected and 82 of those affected died. The lesions were prominent on the head, especially around the eyelids, the nostrils, both sides of the mouth, ventral neck, ventral pale belly, limbs and the root of the tail. Histologically, the epidermal lesions revealed large focal areas of marked acanthosis accompanied by hyperkeratosis and parakeratosis. In the prickle cells, there were multiple small neutrophilic granular inclusions and large eosinophilic homogeneous cytoplasmic inclusions. Electron microscopically, there were numerous poxvirus particles and matrices in the cytoplasm of many prickle cells. Dark blue homogeneous cytoplasmic inclusions in toluidine blue sections consisted of an electron opaque matrix with mature viral particles (160 x 200 x 230 nm). Furthermore, there were clumps of granular matrix containing immature viral particles (200 x 399 nm) in the cytoplasm. Various features of viral developing processes were observed.  相似文献   
30.
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