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991.
In 2012, there were exceptional blooms of D. acuminata in early spring in what appeared to be a mesoscale event affecting Western Iberia and the Bay of Biscay. The objective of this work was to identify common climatic patterns to explain the observed anomalies in two important aquaculture sites, the Galician Rías Baixas (NW Spain) and Arcachon Bay (SW France). Here, we examine climate variability through physical-biological couplings, Sea Surface Temperature (SST) anomalies and time of initiation of the upwelling season and its intensity over several decades. In 2012, the mesoscale features common to the two sites were positive anomalies in SST and unusual wind patterns. These led to an atypical predominance of upwelling in winter in the Galician Rías, and increased haline stratification associated with a southward advection of the Gironde plume in Arcachon Bay. Both scenarios promoted an early phytoplankton growth season and increased stability that enhanced D. acuminata growth. Therefore, a common climate anomaly caused exceptional blooms of D. acuminata in two distant regions through different triggering mechanisms. These results increase our capability to predict intense diarrhetic shellfish poisoning outbreaks in the early spring from observations in the preceding winter.  相似文献   
992.
This study was conducted to evaluate the effect of citric acid (CA) and amino acid chelated trace elements (AA) on the growth, phosphorus (P) utilization efficiency and loading in rainbow trout fed a diet formulated with a low‐fish meal (FM) concentration. A low‐FM basal diet with or without monocalcium phosphate supplementation served as positive and negative control correspondingly. Dietary treatments consisted of the basal diet supplemented either with 1% CA, AA (equivalent to 40 Zn, 20 Mn, and 4 Cu mg/Kg of diet instead of inorganic trace element mix) or a combination of both. Duplicate groups of 35 fish (13.2 g) were fed until apparent satiation during 12 wk. Group of fish fed diets supplemented with 1% CA or AA had a final growth and feed utilization similar to that observed in fish fed the positive control diet (P > 0.05). P absorption was increased with the addition of CA or AA. P retention efficiency rates for these diets were higher in comparison with the rest of the treatments consequently showing the lowest P loading values (P < 0.05). The results indicate that addition of 1% CA or AA, to a low‐FM diet without inorganic P supplementation enhanced fish growth, P retention, and decreased P load to the environment.  相似文献   
993.
A new flavonol diglycoside, 3,5-dihydroxy-7,4'-dimethoxyflavone 3-O-neohesperidoside (1), together with four known flavonol 3-O-neohesperidosides were isolated from the leaves of Costus spiralis and their structures were elucidated by a combination of spectroscopic methods and chemical reactions.  相似文献   
994.
Concentrations and mutual correlations of the cyclic adenosin monophosphate (cAMP), quanosin monophosphate (cGMP), progesterone (P4) and 17-beta-estradiol (E2) were studied in the fluid of the largest follicles in cows, in dependence on the steroid dominance: estrogen-dominant (ED), progesterone-dominant (PD) follicles. Mean cAMP and cGMP concentrations in the follicular fluid in the estrogen-dominant follicles were significantly higher than in the progesterone-dominant follicles; in both cases at P less than 0.01. Significant positive correlation between cAMP and cGMP at P less than 0.001 was stated in the evaluation of the correlations. The cAMP and cGMP concentrations were in significantly negative correlations with the P4 concentration at P less than 0.05, or P less than 0.01 and in significantly positive correlations with the E2, at P less than 0.05. The stated correlations suggest a close mutual relation between cyclic nucleotid and E2, or P4 when the follicles' quality changes.  相似文献   
995.
The effect of low concentrations of mercury taken in the diet (4 mg per a head and day) on the amino acid composition in the proteins of rumen bacteria adhering to the dorsal and ventral parts of the rumen was studied in six sheep. Though the mercury did not influence the amino acid concentration in hydrolyzates of epimural bacteria, low-mercury doses caused significant changes of some amino acids, as compared with the control group of animals. The levels of alanine, histidine, threonine, serine and glycine were significantly decreased and at the same time the levels of proline, valine, isoleucine, tyrosine, lysine and phenylalanine were significantly increased. It was stated in our experiment that the levels of histidine, alanine and threonine in hydrolyzates of epimural bacteria of the rumen were significantly decreased both in the sheep given the balanced feed ration with additions of mercury and nitrogen (according to the standard) and in the sheep given a low-nitrogen diet. Similarly, the levels of proline, tyrosine and phenylalanine in the hydrolizates of epimural bacteria in rumen were significantly increased both with the low-nitrogen diet and in the normal -nitrogen diet with mercury supplement. The results suggest that unexplained disorders frequently occurring in the microbial synthesis in the rumen might be caused by long-continued administration of feed contaminated with extremely low concentrations of heavy metals. The problem deserves detailed investigation in future studies, oriented to explaining the biosynthesis disorders in rumen, reducing the production ability of ruminants.  相似文献   
996.
We determined the thyroxine (T4) concentration in 63 heifers on 0th (day of insemination), 6th and 21st day after first and in repeat-breeder cows after second and third insemination in relation with the breed, age and weight of animals. The examination was carried out with a feed ration balanced according to the Czechoslovak State Standard CSN 46 7070, with all-the-year-round housing, with keeping the uniform time of insemination (8.00--9.00 a. m.) as well as the time of blood sampling (10.00--12.00 a. m.). The animals were inseminated from August to November. The average T4 concentrations, with a successful insemination, fluctuated on 0th day after first, second and third insemination at levels of 56.15 +/- 13.6; 84.6 +/- 10.66 and 89.75 +/- 13.62 nmol X l-1 of serum. As the results show, the lowest T4 concentrations (P less than 0.001; P less than 0.001) on 0th day were recorded in animals becoming pregnant in first insemination. The comparison with non-pregnant animals did not show any statistically significant difference in T4 concentrations. On 0th day of the second insemination, the T4 concentrations in pregnant animals were higher (P less than 0.01) as compared with non-pregnant. On 6th and 21st day after successful first insemination the T4 content increased significantly (P less than 0.001). After second and third successful insemination we recorded in T4 concentrations a moderate decrease on 6th day (P less than 0.01 for third insemination), with insignificant increase on 21st day.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
997.
Impregno-architectonics of neurons in the nuclei of the medial part of hypothalamus was studied in two-month and adult female and male sheep using the methods after Ramón-Moliner and Golgi-Cox. Types of neurons in the hypothalamic nuclei are given, morphology of synaptic conjugations and orientation of nerve processes are described. Ventromedial nucleus has the most interesting structure as a part of the medial hypothalamus: it is ring-shaped in cross-section with paucicellular center, contains various types of neurons and all kinds of synapses which can occur in hypothalamus. Only small numbers of neurons in the pars caudalis of tuberomammillary nucleus, similarly like in nucl. supraopticus and nucl. paraventricularis, are impregnated so that they can be supposed to belong to true neurosecretory nuclei.  相似文献   
998.
999.
1000.
A group of 401 patients suspected for toxoplasmosis was examined by the indirect immunofluorescent antibody test (IFAT). All patients positive in IFAT (176) were examined by the immunosorbent agglutination assay (IgM ISA). In the IgM ISA 154 of them were negative, 10 temporarily and 12 high-positive. Some of high-positive patients were examined repeatedly; decrease of high levels of specific IgM antibodies occurred 2-9 months after the first examination. For the IgM ISA antigen prepared from peritoneal exudate of experimentally infected mice was used. The antigen was stable at 4 degrees C or in liquid nitrogen at least 1 year. The IgM ISA combined with IFAT and IgM IFAT was proved satisfactory for the diagnosis of acquired acute toxoplasmosis and can be recommended for laboratories with lower capacity.  相似文献   
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