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41.
This study examines the impact of taurine on the viability, morphology and acrosome integrity of rabbit spermatozoa in vitro. Semen samples, obtained from four to five sexually mature and healthy New Zealand White rabbits, were pooled in heterospermic semen sample. This was divided and treated with taurine in a concentration of 0 (control), 1.5, 7, 12.5, 50 mM to a final concentration of 108 spermatozoa/ml. The samples were then incubated at 37°C for 4 hr. A combination of fluorescent probes SYBR‐14/propidium iodide/PNA‐Alexa Fluor 647 was used to assess spermatozoa viability and acrosome integrity on a flow cytometer. The sperm morphology was evaluated under a light microscope following fixation in 1.5% paraformaldehyde. The experiment was repeated three times. According to the obtained results, the spermatozoa neither could have benefit from immediate taurine treatment, nor had they after 4‐hr incubation with respect to viability and acrosome integrity. Taurine did not initially alter the total and acrosome morphology of treated spermatozoa nor has it by 4 hr upon treatment. In conclusion, taurine may have no protective effect on the viability, morphology and acrosome integrity of short‐term stored rabbit spermatozoa.  相似文献   
42.
The four major types of leukocytoses are inflammatory, glucocorticoid-associated, catecholamine-associated, and neoplastic. These leukocytoses are distinguished by leukocyte concentrations, microscopic features of leukocytes, and associations with other laboratory data. All laboratory findings need to be interpreted within the context of the case information, including signalment, history, and physical examination findings. Newer assays are being used to differentiate the different forms of leukocyte neoplasia and to distinguish between hyperplastic and neoplastic proliferations.  相似文献   
43.
The gaseous streams containing hydrogen sulphide (H2S) mixed with nitrogen gas (N2) (H2S, 0.00145 mol L-1), H2S mixed with liquefied petroleum gas (LPG) and refinery fuel gas were evaluated, in batch operation, in a bubbled column reactor for desulphurization using ferric sulphate as an oxidant. Further, the ferrous sulphate produced in the process of oxidation is biologically oxidized to ferric sulphate using biomass enriched with Thiobacillus ferrooxidans-JSPR1 in flask culture experiments. In all the cases, the gases were bubbled into the biologically generated ferric sulphate (from ferrous sulphate solution) for the oxidation of H2S. The results indicate that0.00426 mol L-1 of ferric ions are required for reacting with0.00145 mol L-1 of H2S in a gaseous stream containing mixture of N2 and H2S. A concentration of 0.00447 mol L-1 of ferric ions is needed for oxidation of 0.00145 mol L-1 of H2S mixed with LPG. Similarly, the refinery fuel gas containing 0.0031 mol L-1 of H2S requires 0.00428 mol L-1 of ferric ion for effective desulphurization. The ratio of moles of H2S reacted to moles of Fe2+ produced at optimal condition was 0.533, 0.516, 0.510, respectively, for nitrogen mixed H2S, LPG mixed H2S and refinery fuel gas containing H2S. The removal of H2S from these gaseous streams was more than 98%sulphate produced in the process could be biologically oxidized to ferric sulphate with an efficiency of 98%, using shake flask culture experiments. Based on flask culture experiments for biooxidation of commercial ferrous sulphate to generate ferric sulphate, the biokinetic constants viz. yield coefficient y, maximum specific growth rate constant μmax and half saturation rate constant K s were evaluated. The yield coefficient was found to be 0.112 while μmax and K s were observed to be 0.1686 hr-1 and 187.9 mg L-1, respectively. The evaluation of biokinetic constants for bio-oxidation of ferrous sulphate generated during the scrubbing of refinery fuel gas containing H2S indicated the value of μmax and K s as 0.1426 hr-1 and 205 mg L-1, respectively. The value of yield coefficient in this real system was found to be 0.102.  相似文献   
44.
Despite the fact that miombo woodland soils have significant implications in global climate change processes, few studies have been done to characterize and classify the soils of the miombo woodland ecosystem of Tanzania. The current study was carried out to map and classify soils of Kitonga Forest Reserve, which is a typical miombo woodland ecosystem, in order to generate relevant information for their use and management. A representative study area of 52 km2 was selected and mapped at a scale of 1:50,000 on the basis of relief. Ten representative soil profiles were excavated and described using standard methods. Soil samples were taken from genetic soil horizons and analyzed in the laboratory for physico-chemical characteristics using standard methods. Using field and laboratory analytical data, the soils were classified according to the FAO-World Reference Base (FAO-WRB) for Soil Resources system as Cambisols, Leptosols and Fluvisols. In the USDA-NRCS Soil Taxonomy system the soils were classified as Inceptisols and Entisols. Topographical features played an important role in soil formation. The different soil types differed in physico-chemical properties, hence exhibit differences in their potentials, constraints and need specific management strategies. Texture varied from sandy to different loams; pH from 5.1 to 5.9; organic carbon from 0.9 g/kg to 20 g/kg; and CEC from 3 cmol/(+)kg to 24 cmol/(+)kg. Sustainable management of miombo woodlands ecosystem soils requires reduced deforestation and reduced land degradation.  相似文献   
45.
Echinococcosis is an important medical, veterinary and economic concern in India. Ten cysts were randomly selected from each intermediate host species (cattle, buffalo, sheep, goat and pigs). Either the germinal layer (sterile cysts) or protoscoleces (fertile cysts) were collected for molecular characterization. A 434 base pair fragment of the mitochondrial cytochrome oxidase-1 gene was amplified using PCR from each isolate. Ten representative samples (2 from each intermediate host species) were sequenced in both the directions from which readable sequences were obtained from nine for phylogenetic analysis (NCBI, Blast). Phylogenetic analysis of cytochrome oxidase I gene revealed that seven (77.7%) isolates, from cattle (2), pigs (2), buffaloes (1) and goat (2) were clustered with the Indian Buffalo (G3) strain of Echinococcus granulosus, while two (22.2%) isolates from sheep were clustered with the sheep strain (G1) of E. granulosus. Phylogenetic analysis of the cytochrome oxidase-1 gene revealed that the buffalo strain (G3) and common sheep strain (G1) are cycling among livestock in north India and that these strains are highly adapted to cattle, buffalo, sheep, goats and pigs.  相似文献   
46.
Successful hybridization of sterlet (Acipenser ruthenus) × Siberian sturgeon (Acipenser baeri), sterlet × Russian sturgeon (Acipenser gueldenstaedti) and sterlet × European sturgeon (Acipenser sturio) was carried out for the first time using cryopreserved semen of sturgeon males and sterlet × sterlet crosses as controls. Sperm of all three species was diluted with a cryodiluent composed of 23.4 mM sucrose, 0.25 mM KCl, 30 mM Tris (pH 8.0) and 10% methanol. The samples were frozen in plastic straws in the vapor of liquid nitrogen at the height of 3 cm above the level of nitrogen for 3 min. Following thawing approximately 3000 sterlet eggs were fertilized with six straws of frozen-thawed sperm. The hatching rate with sterlet sperm was 30.6% while the hatching rate of A. ruthenus × A. baeri, A. ruthenus × A. gueldenstaedti and A. ruthenus × A. sturio hybrids was 50, 17.4 and 34%, respectively. Morphometric markers as well as random amplified polymorphic DNA (RAPD) assay was used to verify interspecific hybridization.  相似文献   
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48.
Summary In the period 1980–1984 about 70000 selfed seeds of the petunia cultivar Blue Bedder were treated with the chemical mutagens ethidium bromide (EB) and ethylnitroso urea (ENU) with the intention to induce (new sources of) cytoplasmic male sterility (CMS). This work resulted in 27 stable male sterile MS-plants, all derived from the ENU-treatments.Crosses with the normal fertile type and with material carrying restorer genes for the common type of CMS in petunia were made. Results obtained from some MS-plants raise a presumption of genic male sterility, probably of the dominant type, having been induced. More detailed investigations are underway.  相似文献   
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50.
法国和讲法语的北非国家是至今为止小体型、轻体重肉鸡的最大市场。许多法国种鸡育种公司正对这一需求作出反应,如肉鸡生产商Goasduff公司(一个管理出色的家族型企业,对他们的父母代鸡群定下了明确的目标)就拥有大部分小型种鸡。他们采取特殊的管理措施以取得合理的产蛋性能。  相似文献   
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