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1.
Effect of Oil Overlay on Inhibition Potential of Roscovitine in Sheep Cumulus‐Oocyte Complexes 
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下载免费PDF全文 LF Crocomo WC Marques Filho CMV Ulian NS Branchini DT Silva CL Ackermann FC Landim‐Alvarenga SD Bicudo 《Reproduction in domestic animals》2015,50(3):410-416
Inhibitors of cyclin‐dependent kinases, as roscovitine, have been used to prevent the spontaneous resumption of meiosis in vitro and to improve the oocyte developmental competence. In this study, the interference of oil overlay on the reversible arrest capacity of roscovitine in sheep oocytes as well as its effects on cumulus expansion was evaluated. For this, cumulus‐oocyte complexes (COCs) were cultured for 20 h in TCM 199 with 10% foetal bovine serum (Control) containing 75 μm roscovitine (Rosco). Subsequently, they were in vitro matured (IVM) for further 18 h in inhibitor‐free medium with LH and FSH. The culture was performed in Petri dishes under mineral oil (+) or in 96 well plates without oil overlay (?) at 38.5°C and 5% CO2. At 20 and 38 h, the cumulus expansion and nuclear maturation were evaluated under stereomicroscope and by Hoechst 33342 staining, respectively. No group presented cumulus expansion at 20 h. After additional culture with gonadotrophins, a significant rate of COCs from both Control groups (+/?) exhibited total expansion while in both Rosco groups (+/?) the partial expansion prevailed. Among the oocytes treated with roscovitine, 65.2% were kept at GV in the absence of oil overlay while 40.6% of them reached MII under oil cover (p < 0.05). This meiotic arrest was reversible, and proper meiosis progression also occurred in the Control groups (+/?). So, the culture system without oil overlay improved the meiotic inhibition promoted by roscovitine without affecting the cumulus expansion rate or the subsequent meiosis progression. 相似文献
2.
Malm O Guimarães JRD Castro MB Bastos WR Viana JP Branches FJP Silveira EG Pfeiffer WC 《Water, air, and soil pollution》1997,97(1-2):45-51
Informal economy of gold mining has contaminated some important river basins in Amazon. Follow-up studies on critical compartments showed some areas with high Hg levels in fish as well as in human hair samples. Average Hg in piscivorous fish in the Madeira river itself was 846 ppb (N=284) with a maximum of 3921 ppb. Mercury in fish from non polluted areas in this basin shows high variability, even for single species. A seasonal variation in Hg content was observed, with higher values at the end of the dry season. In the upper Tapajós basin comparable values were found for fish but with a definite decreasing trend downstream. Average value for piscivorous fish in the whole Tapajós basin is 482 ppb (N=122) with a maximum value of 3770 ppb. Hair Hg was higher in fishing villages in the Tapajós (average: 17 ppm; with N=432 and maximum value of 176 ppm) than in the Madeira (average: 9 ppm; N=169; maximum 71 ppm), and data from some areas of the Tapajós suggest a decrease with time. Mercury was much higher in urine of goldshop workers in Santarém (low Tapajós) than in Alta Floresta (high Tapajbs) and show a decreasing trend in both cases, probably related to the significant decline in gold mining activities during the study period (1986–1994). 相似文献
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WC Feldman BL Barraclough S Maurice RC Elphic DJ Lawrence DR Thomsen AB Binder 《Science (New York, N.Y.)》1998,281(5382):1489-1493
Global maps of thermal and fast neutron fluxes from the moon suggest three end-member compositional units. A high thermal and low fast neutron flux unit correlates with the lunar highlands and is consistent with feldspathic rocks. The South Pole-Aitken basin and a strip that surrounds the nearside maria have intermediate thermal and fast neutron flux levels, consistent with more mafic rocks. There appears to be a smooth transition between the most mafic and feldspathic compositions, which correspond to low and high surface altitudes, respectively. The maria show low thermal and high fast neutron fluxes, consistent with basaltic rocks. 相似文献
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RC Elphic DJ Lawrence WC Feldman BL Barraclough S Maurice AB Binder PG Lucey 《Science (New York, N.Y.)》1998,281(5382):1493-1496
The Lunar Prospector neutron spectrometer data correlate well with iron and titanium abundances obtained through analysis of Clementine spectral reflectance data. With the iron and titanium dependence removed, the neutron spectrometer data also reveal regions with enhanced amounts of gadolinium and samarium, incompatible rare earth elements that are enriched in the final phases of magma crystallization. These regions are found mainly around the ramparts of the Imbrium impact basin but not around the other basins, including the much larger and deeper South Pole-Aitken basin. This result confirms the compositional uniqueness of the surface and interior of the Imbrium region. 相似文献
6.
Organogenesis and foetal haemodynamics during the normal gestation of healthy black‐rumped agoutis (Dasyprocta prymnolopha,Wagler, 1831) bred in captivity 下载免费PDF全文
下载免费PDF全文 FCA Sousa GT Pessoa LS Moura JR Araújo RPS Rodrigues MAPS Barbosa AN Diniz AB Souza EG Silva LU Lucena MP Sanches OF Silva‐Filho PC Guerra JM Sousa WC Neves FR Alves 《Reproduction in domestic animals》2017,52(1):60-66
The objective of this study was to define the patterns of organogenesis and foetal haemodynamics during the normal gestation of healthy agoutis (Dasyprocta prymnolopha) kept in captivity. Thirty pregnant agoutis that ranged in size from small to medium and weighed between 2.5 and 3 kg underwent B‐mode and Doppler ultrasonography for the biometric evaluation of the foetal organs. The foetal aortic blood flow proved to be predominantly systolic, and the measured flow velocity was 78.89 ± 2.95 cm/s, with a maximum pressure gradient of 2.12 ± 0.27 mmHg. The liver was characterized by its large volume, occupying the entire cranial aspect of the abdominal cavity, and it was associated cranially with the diaphragm and caudally with the stomach. The flow velocity in the portal vein was estimated to equal 12.17 ± 2.37 cm/s, with a resistivity index of 0.82 ± 0.05. The gallbladder was centrally located and protruded cranially towards the diaphragm. The spleen was visualized as an elongated structure with tapered cranial and caudal extremities, and the foetal kidneys were visualized bilaterally in the retroperitoneal region, with the right kidney positioned slightly more cranially than the left. The morphological characterization and hemodynamic analysis of the foetal organs of black‐rumped agoutis via B‐mode and Doppler ultrasonography allow determination of the vascular network and of reference values for the blood flow required for perfusing the anatomical elements essential for maintaining the viability of foetuses at different gestational ages. 相似文献
7.
E. M. BRIDGES 《European Journal of Soil Science》1969,20(2):236-245
The investigation attempts to ascertain rates and amounts of soil erosion from a small unvegetated area (120m×15m). Measurements from markers embedded in the soil indicate a removal of 10 mm per annum on 5°C slopes, 32 mm per annum on 45°C slopes, and 43 mm per annum on 62°C slopes. A sediment trap indicated that in a week when there was 56·8 mm rain, approximately 60 g/sq m was eroded. Results of the work are used in an explanation of the eroded soils of a much larger area, known as the Lower Swansea Valley. 相似文献
8.
Abstract— Hip dysplasia occurred in five of seventeen genotypically normal dogs which were given estradiol for a prolonged period of time. Dysplasia occurred much more frequently in males and in dogs given higher levels of estrogen in early life. The incidence of hip dysplasia was increased in a group often genetically predisposed dogs including three males given estradiol and seven females given testosterone.
Résumé— On donna de l'oestradiol à dix-sept chiens de génotype normal pendant une longue période de temps: cinq d'entre eux présentmènt de la dysplasie de la hanvhe. Cette affection se produisit bien plus fréquemment chez les mâles et chez les chiens qui avaient reçu des quantités d'osetrogène plus importantes dans le jeune âge. La dysplasie de la hanche fut plus fréquente dans un groupe de dix chiens généiquement prédisposés, parmi lesquels trois mâles avaient reçu de l'oestradiol et sept femelles, de la testostérone.
Zusammenfassung— Hüftendysplasie trat bei fünf von siebzehn normalen Hunden auf, ide über längere Zeit Gaben von Östradiol erhielten. Viel häufiger trat die Dysplasie bei männlichen Tieren und bei denjenigen Hunden auf, die höhere Dosen Östeogen schon als Welpen erhielten. Das Auftreten der Hüftendysplasie wurde häufiger in einer Gruppe von zehn genetisch prädisponierten Hunden, darunter drei Rüden, die Östradiol, und sieben Weibchen, die Testosterone erhielten, beobachtet. 相似文献
Résumé— On donna de l'oestradiol à dix-sept chiens de génotype normal pendant une longue période de temps: cinq d'entre eux présentmènt de la dysplasie de la hanvhe. Cette affection se produisit bien plus fréquemment chez les mâles et chez les chiens qui avaient reçu des quantités d'osetrogène plus importantes dans le jeune âge. La dysplasie de la hanche fut plus fréquente dans un groupe de dix chiens généiquement prédisposés, parmi lesquels trois mâles avaient reçu de l'oestradiol et sept femelles, de la testostérone.
Zusammenfassung— Hüftendysplasie trat bei fünf von siebzehn normalen Hunden auf, ide über längere Zeit Gaben von Östradiol erhielten. Viel häufiger trat die Dysplasie bei männlichen Tieren und bei denjenigen Hunden auf, die höhere Dosen Östeogen schon als Welpen erhielten. Das Auftreten der Hüftendysplasie wurde häufiger in einer Gruppe von zehn genetisch prädisponierten Hunden, darunter drei Rüden, die Östradiol, und sieben Weibchen, die Testosterone erhielten, beobachtet. 相似文献
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E. M. BRIDGES 《European Journal of Soil Science》1978,29(2):125-139
Man's initial occupation of the British landscape was subject to broad physical constraints which are still apparent from archaeological evidence and place-name interpretation. The influence of soils in initial settlement establishment is seen to be difficult to interpret several thousand years later as environmental conditions, including soils, have changed. Conversely, man's effect on the soils surrounding his settlements is evident through agricultural and other activities. These activities have increased in their impact with the passage of time. A combination of historical geography and soil studies shows man's interaction with the country's most basic resource. 相似文献
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The State of Bahrain lies in the arid zone on the southern side of the Arabian Gulf. The factors influencing soil formation on the Islands are examined and an account given of the soils. These can be placed in four groups: Solonchaks, Regosols, Yermosols and Fluvisols. The Solonchaks of the northern plain contain unprecedented amounts of gypsum which, in the absence of leaching, give rise to a variety of morphological features. The distribution of Regosols, Yermosols and Fluvisols can be related closely to physiographical location throughout the country. 相似文献