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D Priya NL Selokar AK Raja M Saini AA Sahare N Nala P Palta MS Chauhan RS Manik SK Singla 《Reproduction in domestic animals》2014,49(2):343-351
The objective of this study was to explore the possibility of producing wild buffalo embryos by interspecies somatic cell nuclear transfer (iSCNT) through handmade cloning using wild buffalo somatic cells and domestic buffalo (Bubalus bubalis) oocytes. Somatic cells derived from the ear skin of wild buffalo were found to express vimentin but not keratin and cytokeratin‐18, indicating that they were of fibroblast origin. The population doubling time of skin fibroblasts from wild buffalo was significantly (p < 0.05) higher, and the cell proliferation rate was significantly (p < 0.05) lower compared with that of skin fibroblasts from domestic buffalo. Neither the cleavage (92.6 ± 2.0% vs 92.8 ± 2.0%) nor the blastocyst rate (42.4 ± 2.4% vs 38.7 ± 2.8%) was significantly different between the intraspecies cloned embryos produced using skin fibroblasts from domestic buffalo and interspecies cloned embryos produced using skin fibroblasts from wild buffalo. However, the total cell number (TCN) was significantly (p < 0.05) lower (192.0 ± 25.6 vs 345.7 ± 42.2), and the apoptotic index was significantly (p < 0.05) higher (15.1 ± 3.1 vs 8.0 ± 1.4) for interspecies than that for intraspecies cloned embryos. Following vitrification in open‐pulled straws (OPS) and warming, although the cryosurvival rate of both types of cloned embryos, as indicated by their re‐expansion rate, was not significantly different (34.8 ± 1.5% vs 47.8 ± 7.8), the apoptotic index was significantly (p < 0.05) higher for vitrified–warmed interspecies than that for corresponding intraspecies cloned embryos (48.9 ± 7.2 vs 23.9 ± 2.8). The global level of H3K18ac was significantly (p < 0.05) lower in interspecies cloned embryos than that in intraspecies cloned embryos. The expression level of HDAC1, DNMT3a and CASPASE3 was significantly (p < 0.05) higher, that of P53 was significantly (p < 0.05) lower in interspecies than in intraspecies embryos, whereas that of DNMT1 was similar between the two types of embryos. In conclusion, these results demonstrate that wild buffalo embryos can be produced by iSCNT. 相似文献
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Cheng AF Barnouin-Jha O Zuber MT Veverka J Smith DE Neumann GA Robinson M Thomas P Garvin JB Murchie S Chapman C Prockter L 《Science (New York, N.Y.)》2001,292(5516):488-491
During the Near Earth Asteroid Rendezvous (NEAR)-Shoemaker's low-altitude flyover of asteroid 433 Eros, observations by the NEAR Laser Rangefinder (NLR) have helped to characterize small-scale surface features. On scales from meters to hundreds of meters, the surface has a fractal structure with roughness dominated by blocks, structural features, and walls of small craters. This fractal structure suggests that a single process, possibly impacts, dominates surface morphology on these scales. 相似文献
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Femtosecond laser pulses and coherent two-phonon Raman scattering were used to excite KTaO3 into a squeezed state, nearly periodic in time, in which the variance of the atomic displacements dips below the standard quantum limit for half of a cycle. This nonclassical state involves a continuum of transverse acoustic modes that leads to oscillations in the refractive index associated with the frequency of a van Hove singularity in the phonon density of states. 相似文献
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Conversion of methane to higher hydrocarbons by its low-temperature activation without forming undesirable carbon oxides is of great scientific and practical importance. Methane can be highly activated, yielding high rates of conversion to higher hydrocarbons and aromatics (10 to 45 percent) at low temperatures (400° to 600°C), by its reaction over H-galloaluminosilicate ZSM-5 type (MFI) zeolite in the presence of alkenes or higher alkanes. The methane activation results from its hydrogen-transfer reaction with alkenes. 相似文献
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McEwen AS Hansen CJ Delamere WA Eliason EM Herkenhoff KE Keszthelyi L Gulick VC Kirk RL Mellon MT Grant JA Thomas N Weitz CM Squyres SW Bridges NT Murchie SL Seelos F Seelos K Okubo CH Milazzo MP Tornabene LL Jaeger WL Byrne S Russell PS Griffes JL Martínez-Alonso S Davatzes A Chuang FC Thomson BJ Fishbaugh KE Dundas CM Kolb KJ Banks ME Wray JJ 《Science (New York, N.Y.)》2007,317(5845):1706-1709
Water has supposedly marked the surface of Mars and produced characteristic landforms. To understand the history of water on Mars, we take a close look at key locations with the High-Resolution Imaging Science Experiment on board the Mars Reconnaissance Orbiter, reaching fine spatial scales of 25 to 32 centimeters per pixel. Boulders ranging up to approximately 2 meters in diameter are ubiquitous in the middle to high latitudes, which include deposits previously interpreted as finegrained ocean sediments or dusty snow. Bright gully deposits identify six locations with very recent activity, but these lie on steep (20 degrees to 35 degrees) slopes where dry mass wasting could occur. Thus, we cannot confirm the reality of ancient oceans or water in active gullies but do see evidence of fluvial modification of geologically recent mid-latitude gullies and equatorial impact craters. 相似文献
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Murchie TA Macpherson ML LeBlanc MM Luznar S Vickroy TW 《Equine veterinary journal》2006,38(6):520-525
REASONS FOR PERFORMING STUDY: Most current treatments for placentitis in mares are empirical with few control studies to evaluate their effectiveness. OBJECTIVE: To monitor drug concentrations in allantoic fluid of pregnant pony mares using in vivo microdialysis and establish if this method would be useful for determining allantoic concentrations of drugs in normal mares and those with placentitis. METHODS: Five late gestational pony mares had microdialysis probes inserted into the allantoic fluid using transabdominal ultrasound-guided allantocentesis. Single injections of penicillin G (22,000 u/kg), gentamicin (6.6 mg/kg bwt) and flunixin meglumine (1 mg/kg bwt) were administered i.v. and dialysate samples collected continuously for 24 h. In a separate study, drug concentrations were monitored in allantoic fluid of 2 mares with experimental placentitis induced by intracervical inoculation with Streptococcus equi ssp. zooepidemicus. Drug concentrations were measured by high performance liquid chromatography (penicillin G, flunixin meglumine) or enzyme-linked immunosorbent assay (gentamicin). RESULTS: Penicillin G and gentamicin achieved average peak concentrations of 9.8+/-2.2 and 8.5+/-3.1 microg/ml, respectively, in allantoic fluid of noninfected mares. Pharmacokinetic comparisons indicate that penicillin G persists much longer in allantoic fluid than blood, whereas gentamicin exhibited similar profiles in the 2 compartments. Flunixin meglumine was not detected in allantoic fluid. In infected mares, penicillin G achieved a similar peak concentration in allantoic fluid (11.2 microg/ml) whereas peak gentamicin concentration (3.9 microg/ml) appeared to be reduced relative to drug concentrations in noninfected mares. CONCLUSIONS: Microdialysis is a useful technique for continuous in vivo monitoring of drugs in equine allantoic fluid. Our results indicate that penicillin G and gentamicin undergo effective placental transfer in pregnant mares and in 2 mares that transplacental drug transfer may be altered selectively if active placental infection is present. POTENTIAL RELEVANCE: Further studies are needed to evaluate the feasibility of using increased dose intervals for penicillin G and an increased dose rate of gentamicin to effectively combat placental infections in mares. 相似文献