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2S albumin from buckwheat (Fagopyrum esculentum moench) seeds   总被引:6,自引:0,他引:6  
Sucrose density gradient centrifugation showed that approximately 30% of total buckwheat proteins migrated with a 2S sedimentation coefficient. The main part of that fraction, polypeptides in the range of molecular mass from 8 to 16 kDa, were water soluble and represented albumins. SDS-PAGE analysis in nonreducing and reducing conditions showed that these polypeptides were not linked by disulfide bonds. The albumins make 25% of total salt soluble proteins, but that content is dramatically reduced under S-deficiency conditions. Determination of amino acid composition showed high methionine (9.2%) and lysine (5.6%) contents. That characteristic offers the possibility of transfer of the genes for individual albumin polypeptides to legumes and cereals limited in those essential amino acids to improve their nutritional quality.  相似文献   
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The effect of different concentrations of sulfur (1 and 3 mM) and interruption of sulfur (S) supply for 25 days on the photosynthesis and leaf water relations in young sugar beet plants (Beta vulgaris L.) was studied in water culture, under greenhouse conditions. Interruption of S‐supply significantly reduced the content of sulfur, chlorophylls a+b and carotenoids, leaf area, density of stomatal and epidermal cells, transpiration rate and leaf water potential, while it increased the free proline content and stomatal diffusion resistance. An increase in S concentration in the nutrient medium from 1 to 3 mM did not significantly affect the tested parameters, except for an increase in leaf S content and a decrease of leaf water potential. Sulfur deficiency caused a pronounced decrease of the rate and quantum yield of photosynthetic oxygen evolution under non‐photorespiratory conditions. This was partly the result of the diminished photochemical efficiency of photosystem II reaction centers. Less efficient excitation of PSII reaction centers is most probably the consequence of higher thermal energy dissipation in the reaction centers of S‐starved plants. These data support that S nutrition is one of the factors regulating plant photosynthesis.  相似文献   
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The objective of this study was to determine the number, morphology and ultrastructure of preantral ovarian follicles of buffalo (Bubalus bubalis) foetuses at different ages. Quantification revealed number of primordial, primary and secondary follicles of 48 857 ± 17 506, 26 000 ± 20 452, 18 428 ± 10 875 and 18 375 ± 19 690, 225 ± 349, 326 ± 288 at 12–34 cm and 35–60 cm crown rump length (CRL), respectively. Follicular diameter values were 28.9 (±3.4), 34.7 (±5.9) and 59.4 (±12.6) μm; oocyte diameters were 21.7 (±2.8), 24.3 (±3.4) and 33.0 (±7.7) μm, and the numbers of follicular cells in the follicle equatorial section were 7.1 (±1.4), 12.0 (±2.4) and 13.8 (±2.4) for primordial, primary and secondary follicles, respectively. The primordial follicle consisted of an oocyte surrounded by a layer of flattened follicular cells with a normally eccentric oocyte nucleus. Dispersed Golgi complex, smooth endoplasmic reticulum, rounded mitochondria and several lipid vesicles were observed in the cytoplasm and cell junctions between the follicle cell membranes and the oocyte. This work describes the number, morphometry and ultrastructure of preantral follicles of buffalo foetuses, concluding that folliculogenesis is established between 8 and 34 cm CRL and that follicle number varies individually and according to age and that further studies are needed in this species.  相似文献   
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The objective of this experiment was to assess the features and extent of follicular apoptosis in the water buffalo (Bubalus bubalis) ovary using classical histology and nick end labelling technique. Ovaries (n = 40) procured from the slaughterhouse were used for the study. The sections (5 μm) were used for detection of terminal deoxynucleotidyl transferase‐mediated dUTP‐biotin nick end labelling (TUNEL) and classical histology (H&E). Those follicles showing ≥ 5% TUNEL positivity (TUNEL assay) and pyknotic nuclei (histology) in granulosa cells were classified as atretic. Based on histology, the atretic primary and secondary follicles (%) were 93.82 and 95.62 respectively. The histology study reveals that the rates (%) of atresia in <1, 1–3, 3–5 mm and >5 mm were 36.90, 40.50, 62.84 and 74.5 respectively. Further the atretic tertiary follicles (%) were significantly lower than the primary and secondary classes of follicles. TUNEL assay reveals that the atretic rate (%) of tertiary follicles in <1, 1–3, 3–5 and ≥ 5 mm class follicles were 50.88, 53.84, 81.81 and 36.36 respectively. The percentage of atresia in >5 mm diameter follicles were significantly lower in TUNEL than histology. Percentages of granulosa and thecal cells positive for atresia by TUNEL were 30.7 ± 0.53 and 13.82 ± 0.18 respectively per follicle. The initial structural changes in atretic follicles were seen primarily in the granulosa cells. In severely atretic follicles TUNEL positive granulosa cells along with theca cells have to be considered in assessing the rate and extent of atresia.  相似文献   
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Abstract

Diagnosis and Recommendation Integrated System (DRIS) norms for nitrogen (N), phosphorus (P), potassium (K), sulfur (S), chlorine (Cl) and sodium (Na) and nutrient sufficiency ranges for Aloe vera, Kalanchoe blossfeldiana, Lavandula multifidi, and Rosmarinus officinalis were based on two experiments. DRIS norms and nutrient ratios were computed and selected. Nutrient sufficiency ranges were developed using the data of the whole population according to the DRIS approach. The development of DRIS norms revealed that only K. blossfeldiana and R. officinalis showed limiting nutrients. The nutrient sufficiency ranges for each species expressed in mg g?1 were: A. vera (N (9–28), P (1–3), K (37–48), S (8–10), Cl (47–50), Na (17–37)), K. blossfeldiana (N (16–22), P (2–3), K (35–39), S (7–10), Cl (45–54), Na (7–19)), L. multifida (N (15–16), P (1–7), K (18–37), S (7–8), Cl (41–60), Na (21–49)), R. officinalis (N (9–23), P (2–5), K (31–48), S (7–8), Cl (36–40), Na (7–12)). The establishment of these DRIS norms will useful to manage the nutritional status of the species studied under saline conditions.  相似文献   
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Production of bee products using standards of Modern technology requires high specialization and high productivity of labor adequate facilities and equipment, and coordination of natural bee potential with production characteristics of the wider region. Effectively beekeeping today means using several pastures per year with a yield of 50-60 kg per hive. Mobile beekeeping is the only way to achieve high yields of production and it has considerable advantage over stationary one which is less rentable. Mobile beekeeping require higher investments and labor but with good climate and ecological conditions, one can achieve several times higher income than in stationary beekeeping. Some of the success in mobile beekeeping depends of the selection of hives. The hives must be designed to give the bees the best environment for work and development to be most efficient. Data was collected from 57 beekeepers that live in the district. Data analysis was conducted by using standard statistical and economic processes. Criteria for a recommended for the proposed beekeeping model were incomes and profit per hive. For effective beekeeping and production of bee products, especially honey, beekeeper must have adequate equipment and a good bee hives. Beekeeper must have transportation and additional equipment because their movement depends season on the season and distance to pasture.  相似文献   
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