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431.
The muscles of mastication and their related skull characters in the Caspian seal (Phoca caspica) were anatomically examined and compared with those of the Baikal (Phoca sibirica) and ringed (Phoca hispida) seals. A well-developed masseter muscle was observed in the Caspian seal, whereas the temporal muscle consisted of thin bundles. The skull of the Caspian seal possessed the same thin frontal bone and the dorso-ventrally developed zygomatic arch found in the Baikal seal that are required to install the enlarged eyeball into the orbit. The temporal bone was not robust, and the digastric muscle was well-developed in the ventral space of the auditory bulla. The present results suggest that the skull form of the Caspian seal has changed morphologically from its ringed seal-like ancestors, and suggest that the evolutionary strategy of the muscles of mastication in the Caspian seal is principally consistent with that of the Baikal seal. 相似文献
432.
Arai M Darman J Lewis A Yamamoto JK Darmen J 《Veterinary immunology and immunopathology》2000,77(1-2):71-92
Recombinant human GM-CSF (rhGM-CSF) and erythropoietin (rhEPO) were tested on chronically FIV-infected laboratory cats and uninfected specific-pathogen-free (SPF) cats. In Study 1, a total of eight cats (four cats per group of either infected or uninfected cats) received subcutaneous injection (twice a day) for 2 weeks with 5 microg/kg of rhGM-CSF, while seven cats (three SPF and four FIV-infected cats) served as the placebo-treated control cats. Four of eight rhGM-CSF-treated cats (two cats each from infected and uninfected groups) developed elevated WBC counts which peaked at Days 5-8 of treatment when compared to placebo-treated cats. The elevated WBC counts were attributed to the increase in either neutrophils, lymphocytes, eosinophils, monocytes, or their combinations. The RBC counts, platelet counts, and blood chemistry were not significantly affected by the treatment. Anti-rhGM-CSF antibodies were detected in six of eight rhGM-CSF-treated cats by Day 35 post-first treatment. All rhGM-CSF-treated infected cats but no placebo-treated infected cats had 1-2 log increase in FIV load in the PBMC during the treatment. In vitro studies suggest that rhGM-CSF has an effect on FIV replication in T cells but not in alveolar macrophages. Five of eight rhGM-CSF-treated cats had low-grade fever at 3-6 days of treatment. In Study 2, four cats per group of either infected or uninfected cats were treated (subcutaneously once a day) three times a week for 2 weeks with 100U/kg of rhEPO and monitored as before, while seven cats (three SPF and four FIV-infected cats) served as the placebo-treated control cats. All rhEPO-treated cats had a gradual increase in RBC, Hgb, and PCV counts which peaked at 2-4 weeks post-first rhEPO treatment, whereas none of the placebo-treated cats had significant increase in these parameters. The rhEPO-treated cats also developed elevated WBC counts consisting of either elevated neutrophils, lymphocytes, or their combination by 4 weeks post-first treatment but there was no statistical difference between rhEPO-treated and placebo-treated groups. None of the cats developed anti-rhEPO antibodies and no remarkable changes in blood chemistry, clinical signs, and FIV loads or FIV antibody titers were observed. Overall, rhEPO can be used safely on FIV-infected cats but the use of rhGM-CSF on FIV-infected cats should be performed with discretion. 相似文献
433.
Yamane I Arai S Nakamura Y Hisashi M Fukazawa Y Onuki T 《Preventive veterinary medicine》2000,43(3):203-210
A clinical trial was performed to compare the effects of flumethrin and ivermectin treatments of grazing heifers at one farm in central Japan. 64 heifers were randomly allocated into two groups. Flumethrin (1 mg/kg pour on) was applied approximately once every 3 weeks to heifers in one group and heifers in the second group were injected approximately once every month with ivermectin (200 microg/kg; id). Between groups, no significant differences were detected in the proportions of animals that showed parasitemia of Theileria sergenti and conception risks. Significantly lower average log-transformed nematode-egg counts and higher average daily weight gain were observed in the ivermectin-treated group. Animals with higher body weight at the start of grazing and lower log-transformed total nematode-egg and coccidia-oocyst counts had higher odds of conceiving. Animals with ivermectin treatment, lower body weight at the start of grazing and lower log-transformed coccidia-oocyst count had higher daily weight gain. Ivermectin may be more useful in this farm because of the higher productivity for cattle and lower cost for its usage. 相似文献
434.
Arai S Nakanishi YH Hayashi M 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2000,62(8):861-865
Since the turbidity of nuclear suspensions is known to be correlated with the nuclear morphology, the effects of long-wave ultraviolet (UVA) radiation on Mg2+-dependent structural transition of chromatin in isolated chicken liver nuclei were monitored by measuring the relative turbidity of nuclear suspensions. UVA radiation of the nuclei inhibited the Mg2+-dependent change in relative turbidity of nuclear suspensions in a UVA dose-dependent manner under aerobic conditions but not under N2 conditions. No inhibitory effect of UVA radiation on the change in relative turbidity was observed in the presence of 50 mM NaN3, which scavenges singlet oxygen (1O2) and hydroxyl radicals (*OH). In contrast, 100 mM dimethyl sulfoxide, which primarily scavenges *OH, did not show the inhibitory effect of UVA radiation. The amounts of DNA-protein crosslinks increased with UVA dose under aerobic conditions but not under N2 conditions. The present study showed that UVA radiation of isolated nuclei inhibited the Mg2+-dependent unfolding of condensed chromatin and that O2 is likely to be involved in this process. Furthermore, the formation of DNA-protein crosslinks may contribute to the inhibition. 相似文献
435.
Involvement of apoptosis in the endotoxemic lesions of the liver and kidneys of piglets 总被引:3,自引:0,他引:3
Nakajima Y Mikami O Yoshioka M Arai S Miura K Koike Y Sato M Kobayashi M Nakajima E 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2000,62(6):621-626
The involvement of apoptosis was evaluated in lesions of endotoxemic piglets. A single injection with E. coli O111:B4 lipopolysaccharide (LPS) induced foci of coagulative necrosis in the liver and kidneys. No significant change was observed in these organs at 1.5 hr after LPS injection, but at 6 hr, epithelial cells with chromatin condensation or fragmentation and apoptotic bodies were visible. Foci of coagulative necrosis were formed within 24 hr after LPS inoculation. In and adjacent to the necrotic foci, dead hepatocytes with nuclear condensation or fragmentation were scattered. These dead cells were positively stained by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) methods. Electronmicroscopy revealed apoptotic cells with condensed or fragmented homogeneous nuclear chromatin, and necrotic cells with irregularly destroyed nuclei and cytoplasmic membranes. Apoptotic cell death were also observed in parietal cells of the stomach and lymphocytes in the lymphatic system. DNA ladders with approximately 200-bp multimers were observed in hepatic, renal and thymic samples prepared after 6 and 24 hr of LPS injection by agarose gel electrophoresis. These results suggest that apoptosis is involved in the pathology of swine endotoxemia. 相似文献
436.
T Arai H Ageto T Shinofuji M Sugawara 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1992,54(5):1047-1048
Activities of certain cytoplasmic enzymes were measured in bovine T lymphoma (BTL-PC3 cells). The activities of hexokinase, pyruvate kinase and glucose-6-phosphate dehydrogenase in PC3 cells were elevated as much as 2 or 3-fold of those in bovine thymocyte. The high activities of these enzymes derived from activation of glucose metabolism may reflect the high growth potential of PC3 cells. 相似文献
437.
438.
Aujeszky's disease in a dog 总被引:1,自引:0,他引:1
439.
Conditions for successful cultivation of tumor cells from chickens with avian lymphoid leukosis 总被引:1,自引:0,他引:1
To determine a suitable source of tumor cells that would readily adapt to in vitro growth, attempts were made to culture lymphoid tumor cells in soft agar from several neoplastic organs from chickens with lymphoid leukosis. Of 10 tumors from 7 chickens, cells from only two--both from enlarged bursae--were grown successfully. The remaining 8 tumors failed to propagate. The two cell lines thus established have been propagated by serial passage for more than two years in continuous culture. The two cell lines grow as single, free-floating cells in suspension. Morphologically they are usually round, about 8-10 microns in diameter, and have the characteristics of lymphoblastoid cells. They propagate to a maximum concentration of about 1-2 X 10(6)/ml and release infective virus of subgroup A to titers as high as 10(7) TCID/ml. Their leukosis/sarcoma virus susceptibility phenotype is C/E. Lymphoid tumors developed on chorioallantoic membranes (CAM) of 10-day-old embryonated eggs of the BK line 7 days after inoculation, whereas no tumors developed on CAMs from the 15I line. 相似文献
440.
Arai S Matsui Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2008,70(10):1139-1142
This study was performed to examine normal brainstem auditory evoked potential (BAEP) data for adult Japanese Black cattle and to evaluate whether differences exist in the peak latencies, interpeak latencies (IPL) and waveforms of BAEP between Japanese Black and Holstein cattle. The peaks were detected as major waves I, II, III and V in each group. The threshold of the BAEP waves in the Holstein cattle was 65-75 dB nHL, but the threshold in the Japanese Black cattle was 75-85 dB nHL. The I-III and I-V IPLs were significantly shorter in the Japanese Black compared with the Holstein cattle at an intensity of 105 dB nHL. The present findings suggest that the IPL and wave threshold of BAEP are influenced by bovine breed. 相似文献