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21.
K Sirisha NL Selokar M Saini P Palta RS Manik MS Chauhan SK Singla 《Reproduction in domestic animals》2013,48(4):538-544
This study was carried out to compare the post‐thaw cryosurvival rate and the level of apoptosis in vitro produced zona‐free cloned buffalo blastocysts subjected to slow freezing or vitrification in open‐pulled straws (OPS). Zona‐free cloned embryos produced by handmade cloning were divided into two groups and were cryopreserved either by slow freezing or by vitrification in OPS. Cryosurvival of blastocysts was determined by their re‐expansion rate following post‐thaw culture for 22–24 h. The post‐thaw re‐expansion rate was significantly (p < 0.05) higher following vitrification in OPS (71.2 ± 2.3%) compared with that after slow freezing (41.6 ± 4.8%). For examining embryo quality, the level of apoptosis in day 8 frozen‐thawed blastocysts was determined by TUNEL staining. The total cell number was not significantly different among the control non‐cryopreserved cloned embryos (422.6 ± 67.8) and those cryopreserved by slow freezing (376.4 ± 29.3) or vitrification in OPS (422.8 ± 36.2). However, the apoptotic index, which was similar for embryos subjected to slow freezing (14.8 ± 2.0) or OPS vitrification (13.3 ± 1.8), was significantly (p < 0.05) higher than that for the control non‐cryopreserved cloned embryos (3.4 ± 0.6). In conclusion, the results of this study demonstrate that vitrification in OPS is better than slow freezing for the cryopreservation of zona‐free cloned buffalo blastocysts because it offers a much higher cryosurvival rate. 相似文献
22.
Hiller Edgar Bartaľ Mikuláš Milička Ján Čerňanský Slavomír 《Water, air, and soil pollution》2009,197(1-4):395-402
Water, Air, & Soil Pollution - This study was conducted to evaluate the environmental fate processes of the herbicide (4-chloro-2-methylphenoxy)acetic acid (MCPA) in agricultural soils in the... 相似文献
23.
S Chakraborty R Knoche H Schulze DC Rubie D Dobson NL Ross RJ Angel 《Science (New York, N.Y.)》1999,283(5400):362-365
Rates of cation diffusion (magnesium, iron, and nickel) have been determined in olivine and its high-pressure polymorph, wadsleyite, at 9 to 15 gigapascals and 1100 degrees to 1400 degreesC for compositions that are relevant to Earth's mantle. Diffusion in olivine becomes strongly dependent on composition at high pressure. In wadsleyite, diffusion is one to two orders of magnitude faster than in olivine, depending on temperature. Homogenization of mantle heterogeneities (chemical mixing) and mineral transformations involving a magnesium-iron exchange will therefore occur considerably faster in the transition zone than at depths of less than 410 kilometers. 相似文献
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Microprobe and x-ray diffraction studies of clay coatings in leached soils derived from loess Point analyses of Si, Al, K, Mg, Ca, Fe, Mn, as well as of Zn and Pb of clay coatings in soil thin sections from illuvial horizons of four leached soils were carried out using an electron microprobe (EMA). The K, Mg, Si, and Al content, the Si/Al-molar ratio of coatings and XRD-analyses indicate that the clay coatings consist mainly of illitic clay minerals. This suggests either a mineral-specific displacement of illite or the formation of illitic clay coatings from migrated smectite or expanded illite (“illitization”) through subsequent K uptake. The clay coatings show, with the exception of Fe, Mn, Zn and Pb, only little variation in their chemical composition within the same horizon. Between the horizons of the investigated soils, however, distinct differences in the total element content, especially in the K content may occur. The strong vertical variation of the K content in clay coatings in some horizons is probably due to acidic conditions and lateral infiltration which lead to an increased weathering of illite and the depletion of K. The EMA results show that Pb is predominantly bound in Fe-Mn-Oxide coatings on the surface of clay minerals or in Fe-Mn-Oxide precipitates within clay coatings. Microanalyses of K depleted clay coatings indicate on the other hand an increased fixation of Zn in expanded illites. 相似文献
26.
A 6-month-old alpaca presented for lethargy, failure to thrive and leucocytosis. Diagnostic procedures, including thoracic ultrasound, radiographs and a computed tomography scan, were used to document a thoracic mass. Based on appearance and ultrasound-guided aspiration of purulent material, the mass was determined to be a large abscess. The abscess was treated with surgical drainage and long-term antibiotic therapy. The origin of this thoracic abscess was felt to be the caudal mediastinum, secondary to bacterial seeding of the caudal mediastinal lymph nodes. Although an aetiological agent was not definitively determined, the most likely was Actinomyces spp or Arcanobacterium pyogenes. The alpaca made a complete recovery following treatment. 相似文献
27.
Polyethylene glycol 1540, added to culture solution in amounts sufficient to reduce the water potential to -10 atmospheres, inhibited respiration in Chlorella much more than mannitol solutions at -10 atmospheres. This occurred despite the purification of the polyethylene glycol by passage through exchange columns. The toxic properties, which developed some time after purification, increased with time of storage of solutions of polyethylene glycol 1540 at room temperature. 相似文献
28.
V Martinsen V Alling NL Nurida J Mulder SE Hale C Ritz 《Soil Science and Plant Nutrition》2013,59(5):821-834
AbstractSoil acidity may severely reduce crop production. Biochar (BC) may increase soil pH and cation exchange capacity (CEC) but reported effects differ substantially. In a systematic approach, using a standardized protocol on a uniquely large number set of 31 acidic soils, we quantified the effect of increasing amounts (0–30%; weight:weight) of three types of field-produced BCs (from cacao (Theobroma cacao. L.) shell, oil palm (Elaeis guineensis. Jacq.) shell and rice (Oryza sativa. L.) husk) on soil pH and CEC. Soils were sampled from croplands at Java, Sumatra and Kalimantan, Indonesia. All BCs caused a significant increase in mean soil pH with a stronger response and a greater maximum increase for the cacao shell BC addition, due to a greater acid neutralizing capacity (ANC) and larger amounts of extractable base cations. At 1% BC addition, corresponding to about 30 tons ha?1, the estimated increase in soil pH from the initial mean pH of 4.7 was about 0.5 units for the cacao shell BC, whereas this was only 0.05 and 0.04 units for the oil palm shell and rice husk BC, respectively. Besides depending on BC type, the increase in soil pH upon the addition of each of the three BCs was mainly dependent on soil CEC (low CEC resulting in stronger pH increase), and to a lesser extent on initial soil pH (higher initial pH resulting in stronger pH increase). Addition of BC also increased the amount of exchangeable base cations (cacao shell ? oil palm and rice husk) and CEC. Through this systematic screening of the effect of BC on pH and CEC of acidic soils, we show that a small addition of BC, in particular if made of cacao shell, to acidic agricultural soils increases soil pH and CEC. However, the response is highly dependent on the type, quality and amount of the added BC as well as on intrinsic soil properties, mainly CEC. 相似文献
29.
Thais M Menegheti Juliana T Wagatsuma Acácio D Pacheco Beatriz Perez Cynara M Pacheco Caio JX Abimussi Paulo PS dos Santos Valéria NL de Souza Oliva 《Veterinary anaesthesia and analgesia》2014,41(1):97-104
ObjectiveThe present study aimed to investigate the influence of methadone on cardiorespiratory parameters, electrocardiogram and clinical sedation in dogs. Further possible side effects are reported.Study designProspective experimental cross-over study.DogsEight, 1–4-year-old, various breeds of dogs of both genders weighing 9–36 kg.MethodsEach dog was treated three times: methadone 0.3 mg kg?1 (M0.3), 0.5 mg kg?1 (M0.5) and 1.0 mg kg?1 (M1.0) intramuscularly. Respiratory rate, heart rate and arterial blood pressure were recorded as well as electrocardiographic evaluation of lead II. Clinical sedation in each treatment received a score (0–3) after drug administration and at 30 minute intervals until scores and measurements returned to baseline values.ResultsA significant decrease in heart rate was seen with each dose of methadone and bradycardia (HR<60 bpm) was noted in a few dogs at each dose. A clinically significant arrhythmia occurred in one dog at 1 mg kg?1 that required reversal with butorphanol. There was no significant difference in SAP, MAP and DAP between treatments. Some side effects such as salivation, defecation, vocalization and panting, after administration of methadone were observed. There were no differences in mean values of heart rate, P-wave and QRS complex duration and QT interval between treatments.Conclusion and clinical relevanceMethadone administration was associated with panting and a decrease in heart rate at all doses tested in this study. The cardiac rhythm should be monitored carefully in dogs when methadone is administered on its own, especially at higher doses. 相似文献
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