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211.
Plant Foods for Human Nutrition - Herbs used for medical purposes are required to meet high pharmacopoeial quality standards, whereas spices used as additives to dishes and food products do not...  相似文献   
212.
Journal of Soils and Sediments - The studies aimed to reconstruct major phases of litho-morpho-pedogenic processes and past environmental changes in the Baltic coastal zone near Podd?bie...  相似文献   
213.
Spermiation and changes in androgen (testosterone, T and 11-ketotestosterone, 11-KT) levels were studied in sterlet (Acipenser ruthenus) treated with GnRH agonist implants (dAla6-Pro9-LHRHa) at 25 and 75?μg?kg?1 b.w. and compared with those males treated with 4?mg?kg?1 b.w. of carp pituitary extract (CPE) and 3 pellets of Ovopel kg?1 b.w., which contains dAla6-Pro9NEt-mGnRH and metoclopramide. Sperm quality (sperm mass, spermatozoa concentration and sperm motility and velocity) was evaluated 24, 48 and 72?h after hormonal treatments. Males did not release sperm in the control group injected with physiological solution, while sperm could not be collected 7?days after treatments in all hormonally treated groups. Spermiation rates were 100?% in the CPE and Ovopel groups and 25–50?% in the GnRHa-treated groups. Sperm production was significantly lower in the GnRHa-treated groups than in the CPE and Ovopel groups and decreased 72?h after hormonal treatment. Sperm motility and velocity were higher in the Ovopel and GnRHa (75?μg) groups compared to the CPE and GnRHa (25?μg) groups and decreased 72?h after hormonal treatment. Androgens were only affected in spermiating males and changed in the Ovopel and GnRHa (75?μg) after hormonal treatment. Significant correlations were observed between sperm production, sperm motility and sperm velocity, but not androgens. The present study suggests involvement of dopamine in sturgeon spawning. Additionally, better sperm quality observed in the Ovopel group and particularly sperm motility in the GnRHa (75?μg) suggests enhancement of sperm quality in sturgeon treated with GnRHa. Therefore, further study is needed to induce fully spermiation using GnRHa implants in combination with a dopamine inhibitor.  相似文献   
214.
Six different isoquinoline alkaloids (sanguinarine, chelerythrine, berberine, coptisine, allocryptopine, and protopine) were extracted by butanol and octanol from aqueous solution, pH 4.5. The samples were analyzed by HPLC. Butanol extraction was non-selective, alkaloids passed into organic phase in 83–98%. Octanol extraction provided more selective yields: sanguinarine 99%, chelerythrine 94%, berberine 18%, coptisine 16%, allocryptopine 7.5%, protopine 7%. Further, we tested octanol treatment of extract from Dicranostigma lactucoides. The octanol extraction yields were also selective: sanguinarine 98%, chelerythrine 92%, chelirubine 92.5%, protopine 6% and allocryptopine 3.5%. 6-Butoxy-5,6-dihydrosanguinarine and 6-butoxy-5,6-dihydrochelerythrine were prepared and their NMR and MS data are reported and discussed.  相似文献   
215.
Different field isolates of the ‘beet poleroviruses’ Beet mild yellowing virus (BMYV) and Beet chlorosis virus (BChV) (genus Polerovirus, family Luteoviridae) collected in France and Poland were evaluated for transmissibility from and to sugar beet plants by different aphid species. In general, both BMYV and BChV were efficiently transmitted by Myzus persicae and by a French clone of Macrosiphum euphorbiae. In contrast, transmissibility of the two poleroviruses by an English clone of M. euphorbiae was evidently weaker, although the aphid samples contained the virus as demonstrated by RT-PCR. None of the BMYV or BChV isolates was transmitted by Aphis fabae or Myzus ascalonicus. In attempting to correlate biological properties with molecular variations, the RT proteins were sequenced. Some amino acid point variations, presumably affecting aphid transmissibility, were identified.  相似文献   
216.
The present study examined the influence of extract obtained from the interior of cells of yeast, Saccharomyces cerevisiae (NuPro®), on the growth, proximate composition, nonspecific cellular and humoral defense mechanisms, and protection against furunculosis in pikeperch (Sander lucioperca). It was noted that eight weeks of supplementation with 40 g of NuPro® kg?1 feed (containing approximately 0.22 % exogenic nucleotides) enhanced pikeperch innate immunity. Increased serum lysozyme activity and total Ig levels (P < 0.05) were noted in the NuPro®-fed group, which indicated the activation of nonspecific humoral defense mechanisms. Brewer’s yeast extract also stimulated nonspecific cellular defense mechanisms as indicated by the increased metabolic activity of blood phagocytes and pronephric macrophages, and in the increased intracellular killing activity of phagocytes and proliferative responses of T and B lymphocytes (P < 0.05). Additionally, reduced mortality (15 %) after the in vivo challenge with pathogenic Aeromonas salmonicida suggested that NuPro® activated nonspecific protection against furunculosis in pikeperch. The experimental feed did not have a significant impact on the growth or proximate composition of the fish (P > 0.05).  相似文献   
217.
218.
The impact of the relative time of emergence on the growth allometry of Galium aparine L. (cleavers) in competition with Triticum aestivum L. (spring wheat) was studied in a greenhouse experiment. The hypothesis that changes in growth allometry, particularly in the leaf area/height ratio, caused by a shift in the relative time of emergence, could lead to plants overcoming the competition or to competitive suppression was tested. The plant height, dry weight, total leaf area and vertical distribution were analyzed during the first 83 days of growth. The late emergence of G. aparine substantially influenced the growth dynamics for the dry weight and total leaf area. The dynamics of height growth were affected only following a significant delay in G. aparine emergence. The ratio of dry weight to total leaf area was almost unaffected by the competition. By contrast, the allometric relationship between the plant height and total leaf area was highly sensitive to the relative time of emergence. The results suggest that height is the most important growth trait for the plants to resist increasing competition. Even though the plants responded to competition with elongation, the physiological costs linked with “shade avoidance” caused reductions in the dry weight and leaf area growth that resulted in the total suppression of the late‐emerging individuals, in particular when their emergence was >10 days after that of the crop.  相似文献   
219.
The role of the seminal fluid antioxidant system in protection against damage to spermatozoa during in vitro sperm storage is unclear. This study investigated the effect of in vitro storage of sterlet Acipenser ruthenus spermatozoa together with seminal fluid for 36 h at 4 °C on spermatozoon motility rate and curvilinear velocity, thiobarbituric acid reactive substance level, and components of enzyme and non-enzyme antioxidant system (superoxide dismutase and catalase activity and uric acid concentration) in seminal fluid. Spermatozoon motility parameters after sperm storage were significantly decreased, while the level of thiobarbituric acid reactive substances, activity of superoxide dismutase and catalase, and uric acid concentration did not change. Our findings suggest that the antioxidant system of sterlet seminal fluid is effective in preventing oxidative stress during short-term sperm storage and prompt future investigations of changes in spermatozoon homeostasis and in spermatozoon plasma membrane structure which are other possible reasons of spermatozoon motility deterioration upon sperm storage.  相似文献   
220.
In the laboratory, a commercial neem-based insecticide—Nimbecidine®—was evaluated as a potential pest management tool for the terrestrial snail, Monacha obstructa (Pfeiffer, 1842) (Hygromiidae). Effects of different concentrations of the botanical insecticide on food consumption and egg hatchability of the terrestrial snail were studied. Generally, food consumption of immature and adult snails decreased as the concentrations of Nimbecidine® increased. At the highest concentration (10 ml/l), the snails avoided contacting with food completely. The food intake of immature individuals was significantly (p < 0.05) more affected by the Nimbecidine® treatment (at 1.25 ml/l) than that of adults. LC50 of Nimbecidine® for the treated eggs was 2.18 ml/l, and eggs failed to hatch at concentration of 10 ml/l. Nimbecidine® showed sufficient biological activity against the food consumption and eggs viability of M. obstructa, thus the preparation has a potential to protect field crops from this pest snails.  相似文献   
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