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81.
Somatic embryogenesis is the preferred method for cell-to-plant regeneration of grapevine. In this study, we tested the embryogenic capacity of anther-derived calli from 59 grape genotypes, representing a diverse group of Vitis vinifera and hybrid varieties, and hybrids and accessions of non-vinifera Vitis species. Most genotypes were tested on two types of media: MST1 medium, which contained plant growth regulators (PGRs) 2,4-dichlorophenoxyacetic acid (2,4-D) and thidiazuron (TDZ), and MSE medium, which contained 2,4-D and 6-benzylaminopurine (BAP). Twenty-four of the grape genotypes produced embryogenic callus on one or both of these media, eighteen of which have not been reported to form somatic embryos before. The results also suggested that the various PGR combinations are differentially effective at inducing somatic embryos in various classes of grape genotypes. For example, seven of the eight V. vinifera conv. occidentalis varieties brought forth somatic embryos on MSE medium, and three out of four American Vitis genotypes produced somatic embryos on MST1 medium. We could not observe any apparent association between frequency of callus formation and embryogenic capacity of the anthers. 相似文献
82.
Jitka Hamáčková Andrea Lepičová Miroslav Prokeš Pavel Lepič Pavel Kozák Tomáš Policar Leon Andrzej Stanny 《Aquaculture International》2007,15(3-4):255-265
The ide Leuciscus idus (Linnaeus 1758) belongs to autochthonous, less frequent and vulnerable fish species in the frame of ichthyofauna of the Czech
Republic. It was the reason for testing the possibility of captive breeding and production of fry in a controlled environment.
The goal of this paper was to find the optimal transfer time of ide larvae from live food (Artemia salina nauplii) to dry starter feed providing good survival and growth. At the end of the experiment, high values of cumulative
survival (in percentages) and individual weight (in milligrammes) were found for ide fry in groups D (90.6%, 178.6 mg; 15 days
A.
salina + 10 days starter feed), A (89.9%, 169.9 mg; A. salina only) and C (88.6%, 160.4 mg; 10 days A. salina + 15 days starter feed). Significantly lower values of the given parameters were found in group B (57.1%, 92.6 mg; 5 days
A. salina + 20 days starter feed), and the lowest ones were in group E (29.8%, 75.6 mg; starter feed only). Mean values of the level
of ontogenesis at the end of the experiment in fry of A–E groups were analogous to length and weight growth. Groups D, C and
A consisted of juveniles only (J1, J2), and groups B and E consisted of larvae and juveniles (L4, L5, L6, J1, J2). Condition
and production parameters [Fulton’s coefficient of condition (FWC), total length (TL), weight (w), specific growth rate (SGR),
food conversion ratio (FCR), cumulative survival] and relationships between basic lengths TL, fork length (FL) and standard
length (SL) were evaluated. 相似文献
83.
Relationship between biochemical constituents of fish semen and fertility: the effect of short-term storage 总被引:5,自引:0,他引:5
Spermatozoa and seminal plasma obtained from rainbow trout and whitefish were analyzed in respect to their aspartate aminotransferase
(AspAT) and alkaline phosphatase activities. In particular, the experiments characterized AspAT optimum pH, optimization of
assay conditions and action of coenzyme, pyridoxal 5-phosphate (vitamin B6). The effect of short-term semen storage at 0°C on biochemical indicators and fertilization rate was examined in both species.
The concentrations of reduced and oxidized ascorbic acid in seminal plasma of both species were several folds higher than
in spermatozoa and blood plasma of fish. Highly significant correlations were found for both species between AspAT activity
(sperm or seminal plasma) and fertilization rate (% of eyed-stage or hatched embryos). For rainbow trout, highly significant
correlations were found between sperm concentration, motility and fertilization rate. These results suggest that several biochemical
indicators of seminal plasma can be used as measures of sperm quality of fish. Some common biochemical parameters for fish
and mammal's semen provide evidence for using fish sperm as a model in biomedical research. 相似文献
84.
Joanna Maaczewska Edyta Kaczorek‐ukowska Roman Wjcik Wojciech Rkawek Andrzej K. Siwicki 《Journal of animal physiology and animal nutrition》2019,103(3):882-893
Nisin, a lantibiotic bacteriocin, has been used for years as a natural food preservative. In addition to its antimicrobial activity, nisin also shows immunomodulatory properties, and the nisin‐producing Lactococcus lactis strain has been successfully tested as a probiotic in weaned piglets. However, the impact of nisin on porcine immune cells has not yet been explored. The objective of the present study was to examine the in vitro immunomodulatory effect of nisin on porcine peripheral blood leucocytes. The whole heparinized blood samples or freshly isolated peripheral blood mononuclear cells (PBMCs) were incubated with different nisin concentrations (0, 1.56, 3.125, 6.25, 12.5, 25 or 50 µg/ml) for 1, 24, 48 or 72 hr. Escherichia coli bacteria were used to stimulate blood phagocytes, while concanavalin A and lipopolysaccharide from E. coli were used as mitogens. Control cells remained unstimulated. MTT colorimetric assay was used to evaluate PBMCs viability and mitogenic response. Phagocyte activity and T‐cell proliferation were measured by flow cytometry. Flow cytometer was also used for immunophenotyping of T cells. Cytokine levels in the culture media were determined using commercial immunoassay (ELISA) kits. The highest concentration of nisin exhibited proliferative activity (p ? 0.05), stimulated interleukin‐1 beta (IL‐1β) and interleukin‐6 (IL‐6) production (both at p ? 0.001), and increased the percentage of CD4+CD8+ T cells (p ? 0.001) among unstimulated leucocytes. After cell stimulation, however, the highest nisin concentration showed antiproliferative activity (p ? 0.05), decreased phagocytic functions (p ? 0.05) and inhibited the synthesis of IL‐6 (time‐ and concentration‐dependent effect). As a typical bacterial product, nisin had a stronger impact on innate immune cells, and its effect on T cells was likely a consequence of the modulation of the activity of antigen‐presenting cells. Nisin may be a good candidate as an immunomodulator in pig breeding. 相似文献
85.
Z. M. Lisowski R. S. Pirie A. T. Blikslager D. Lefebvre D. A. Hume N. P. H. Hudson 《Equine veterinary journal》2018,50(3):292-303
Post‐operative ileus (POI) is a serious condition which any horse undergoing abdominal surgery is at risk of developing, leading to increased hospitalisation time and resulting costs. Advances in the understanding of the development of equine POI are mainly based on human and rodent literature, where manipulation‐induced inflammation has been identified as a trigger, with activation of resident muscularis externa macrophages playing a crucial role in the pathophysiology. Despite many pharmacological trials in all species, there is no single completely successful treatment for POI, highlighting that the condition is multifactorial in cause and requires a multimodal approach to minimise its incidence. 相似文献
86.
Marta Henklewska Aleksandra Pawlak Justyna Kutkowska Hanna Pruchnik Andrzej Rapak Bozena Obminska‐Mrukowicz 《Veterinary and comparative oncology》2019,17(4):497-506
The anticancer activity of novel platinum derivative, a complex of platinum with tris(2‐carboxyethyl)phosphine (Pt‐TCEP), has been evaluated in canine (D‐17) and human osteosarcoma (U2‐OS) cell lines. Viability of cells after incubation for 24 or 72 hours with increasing concentrations (0.625, 1.25, 2.50, 5, 10 and 20 μM) of Pt‐TCEP was tested in an MTT assay and compared to effect of cisplatin. Longer‐term effect of Pt‐TCEP was evaluated in the colony‐forming unit assay after 24 hours exposure to the Pt‐TCEP (2 and 3 μM) and subsequent incubation for 2 weeks. The influence of the compound on the cell cycle was measured after 24 hours treatment with Pt‐TCEP (3 μM). Its pro‐apoptotic activity was examined after 24 hours treatment with Pt‐TCEP (1.25, 2.50, 5, 10 and 20 μM) using flow cytometry. Expression of main proteins involved in apoptosis was measured after exposure for 24 hours to 3 or 5 μM Pt‐TCEP in Western Blot. The compound much more effectively decreased cell viability than cisplatin in case of both cell lines. IC50 of Pt‐TCEP was 5.93 ± 0.12 in D‐17 and 3.45 ± 0.14 in U2‐OS cell lines after 24 hours, and 1.77 ± 0.14 in D‐17 and 1.53 ± 0.11 in U2‐OS after 72 hours (P < .05). The compound arrested cells in the G2/M phase and inhibited the ability of cells to form colonies. Pt‐TCEP induced caspase‐dependent apoptosis. The expression of the anti‐apoptotic Bcl‐XL protein was decreased after Pt‐TCEP treatment in both cell lines. The results confirmed anti‐cancer activity of Pt‐TCEP against canine and human osteosarcoma cell lines. 相似文献
87.
利用胚和胚珠的离体培养获得甘蓝型油菜与青花菜的种间杂种 总被引:5,自引:0,他引:5
以波兹南农业大学植物遗传育种系提供的甘蓝型胞质雄性不育油菜为母本与青花菜杂交 ,授粉后 1 9d,观察其种间杂交的有效性 ,并对其胚和胚珠进行离体培养。结果表明 :种间杂交的亲和性及胚珠退化时间随杂交组合不同而异 ,亲本的基因型对其有很大的影响。胚和胚珠的离体培养可有效地克服合子后的发育障碍获得种间杂种植株 相似文献
88.
89.
90.
Albert Rovira Rhoda Ballinger Carles Ibáñez Paul Parker M. Dolores Dominguez Xavier Simon Andrzej Lewandowski Boris Hochfeld Marian Tudor Liesbeth Vernaeve 《Journal of Soils and Sediments》2014,14(8):1493-1512