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11.
The existence of CD3(+)CD4(-)CD8(-) T cells in thymus and spleen has already been known. However, because of the presence of large amounts of thrombocytes in peripheral blood (PB), the proportion of CD3(+)CD4(-)CD8(-) T cells in PB has yet to be investigated. Therefore, the proportion of peripheral T cell-subsets was investigated in 6-week-old chickens. The percentage of CD3(+) cells, CD4(+) cells, CD8 alpha(+) cells, CD8 beta(+), and CD3(+)CD4(-)CD8(-) cells was 76%, 41%, 14%, 5%, and 15%, respectively. The proportion of CD3(+)CD4(-)CD8(-) cells in PB increased during egg-laying periods and in chickens treated with an analog of estrogen, while it decreased with age and in response to restraint stress. All of the CD3(+)CD4(-)CD8(-) cells expressed TCR1, and did not have NK activity. CD3(+)CD4(-)CD8(-) cells represent about 60% of peripheral TCR1(+) cells. These findings indicate that the proportion of CD3(+)CD4(-)CD8(-) cells is regulated by the endocrine and nerve systems.  相似文献   
12.
A new cell line named CCF‐K104 predominantly consisting of fibroblastic cells showed optimal growth at temperatures from 25 °C to 30 °C. Serial morphological changes in the cells induced by Cyprinid herpesvirus 3 (CyHV‐3) included cytoplasmic vacuolar formation, cell rounding and detachment. Mature virions were purified from CyHV‐3‐infected CCF‐K104 cells by sucrose gradient ultracentrifugation and had a typical herpesvirus structure on electron microscopy. Infectious CyHV‐3 was produced stably in CCF‐K104 cells over 30 viral passages. Our findings showed that CCF‐K104 is a useful cell line for isolation and productive replication of CyHV‐3. A temperature shift from 25 °C to 15 °C or 35 °C did not allow serial morphological changes as observed at 25 °C for 14 days. Under the same conditions, real‐time PCR showed that CyHV‐3 was present with low viral DNA loads, suggesting that CyHV‐3 may establish latent infection in CCF‐K104 cells. Amplification of the left and right terminal repeat sequences of the CyHV‐3 genome arranged in a head‐to‐tail manner was detected by nested PCR following an upshift in temperature from 25 °C to 35 °C. The PCR results suggested that the circular genome may represent a latent form of CyHV‐3.  相似文献   
13.
Cortical microtubules (MTs) in differentiating compression wood tracheids of Taxus cuspidata stems were visualized by confocal laser microscopy. They were oriented obliquely at an angle of about 45° to the tracheid axis during formation of the secondary wall. Artificial inclination altered the pattern of alignment of MTs. Banding MTs were helically oriented late during the formation of the secondary walls. These results indicate that MTs might control the orientation and localized deposition of cellulose microfibrils in the secondary walls of compression wood tracheids.Part of this report was presented at the 46th annual meeting of the Japan Wood Research Society, Kumamoto, April 1996  相似文献   
14.
Unconditional quantum teleportation   总被引:5,自引:0,他引:5  
Quantum teleportation of optical coherent states was demonstrated experimentally using squeezed-state entanglement. The quantum nature of the achieved teleportation was verified by the experimentally determined fidelity Fexp = 0.58 +/- 0.02, which describes the match between input and output states. A fidelity greater than 0.5 is not possible for coherent states without the use of entanglement. This is the first realization of unconditional quantum teleportation where every state entering the device is actually teleported.  相似文献   
15.
16.
It is well known that chicken B cells develop in the bursa of Fabricius (BF), which is categorized as gut-associated lymphoid tissue (GALT). Chicken GALT also includes Peyer's patch (PP) and cecal tonsil (CT). The relationship between these tissues in GALT during B cell development is currently unknown. In this study, we conducted comparative examination of PP, CT and BF development during embryogenesis using immunohistochemical staining. On day 13 of embryogenesis (E13), accumulation of MHC class II(+) cells was observed in the intestine. Thereafter, Bu-1(+) cells and IgM(+) cells appeared, and their number continuously increased at the same sites where MHC class II(+) cells were present. Similar results were obtained in the CT. The locations of embryonic PP were limited to two sites; near the Meckel's diverticulum and the ileocecal junction. Anlage of bursal follicles first appeared at E13 and developed thereafter. Immigration of Bu-1(+) cells to bursal follicles began at E13, and the number of Bu-1(+) cell subsequently increased. When the follicle of BF was eliminated from the embryo by treatment with testosterone, development of PP and CT were observed. We concluded therefore that the development of PP and CT start during late embryogenesis at the same time as the follicle of BF, and that appearance of surface IgM(+) cells in PP and CT is independent form the development of the follicle of BF.  相似文献   
17.
Transference of Dietary Veterinary Drugs into Eggs   总被引:1,自引:0,他引:1  
Twelve veterinary drugs, bacitracin (BC), chloramphenicol (CAP),chlortetracycline (CTC), oxytetracycline (OTC), tylosin (TS), amprolium (APL), furazolidone (FZD), nicarbazine (NCZ), ormetoprium (OMP), sulfadimidine (SDD), sulfadimethoxine (SDM) and sulfamonomethoxine (SMM) were fed to laying hens for 14 days, each at a dietary concentration of 500 mg/kg. The concentrations of the drugs in the eggs from these birds were determined at 2-day intervals for 14 days after the start of feeding. The relationship between the concentrations of the drugs (mg/kg) in the eggs and the number of days after the start of feeding was analysed by regression and covariance analyses. The concentrations of the drugs in the eggs became constant after 4 days for OTC, TS, FZD and all the sulfonamides, and after 6 days for CAP, APL, NCZ and OMP. No BC or CTC was detected in the eggs. The transfer rates of the 10 drugs (excluding BC and CTC) from the feed to eggs varied from 0.005% for TS up to 1.540% for SDD.  相似文献   
18.
CD30 ligand (CD30L) and tumor necrosis factor (TNF)-related apoptosis inducing ligand (TRAIL) are members of the TNF-superfamily that have many important biological activities in cell proliferation and apoptotic death. In this study, both genes in the chicken were cloned and their expression was analyzed. Complementary DNA fragments were obtained from a suppressive subtractive hybridization library with or without lipopolysaccharide (LPS)-stimulation. Chicken CD30L consists of 1,152 base pairs (bp) with an open reading frame (ORF) of 720 bp having 36.4% identity with human CD30L, whereas chicken TRAIL is 1,134 bp long with an ORF of 912 bp having 54.4% identity with human TRAIL. Chicken CD30L was expressed at high levels in the spleen, bursa of Fabricius and in the chicken monocytic leukemia cell line, IN24. Stimulation with LPS in the spleen, bursa of Fabricius and the IN24 cell line did not affect CD30L expression. The gene expression of chicken TRAIL was essentially to the same level in all tissues examined. The time course of expression was not significantly altered by LPS-stimulation in the spleen, thymus and bursa of Fabricius, but reached a maximal level 8 hr after stimulation in the IN24 cell line. The high level expression of both genes in lymphoid organs and IN24 cell line indicates that chicken CD30L and TRAIL may also play an important role in apoptotic signal transduction and the regulation of cell proliferation in the immune system.  相似文献   
19.
Fisheries Science - We aimed to determine the spawning period of black sea bream Acanthopagrus schlegelii in Hiroshima Bay, Japan, based on the distribution of its eggs, to assist in the resource...  相似文献   
20.
The effects of novobiocin (range 0.0125–2 mmol/L) on the hydroxylation of testosterone, the N-demethylation of erythromycin, and the glucuronidation of -naphthol and paracetamol were studied using pig hepatic microsomes, pooled from five animals. The final concentrations of these substrates in the incubation mixtures were selected to meet Vmax conditions. Novobiocin caused a concentration-dependent inhibition of the glucuronidation of paracetamol; the formation of -naphthol-glucuronide was reduced to a lesser degree. These results confirm and extend earlier findings in laboratory animal species that novobiocin inhibits UDP-glucuronosyltransferases (UDPGTs). Moreover, novobiocin strongly inhibited 6-hydroxylation of testosterone. The microsomal N-demethylation of erythromycin and hydroxylation of testosterone at the 15 position were less affected by novobiocin. These results suggest that novobiocin inhibits not only UDPGTs, but also cytochrome P450 (CYP) enzyme activities, probably those belonging to the CYP3A subfamily. More research is needed to reveal which CYPs and UDPGTs are affected by novobiocin in vivo, in order to improve the understanding and probably the predictability of potential drug interactions with this antibiotic.  相似文献   
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