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41.
OBJECTIVE: To assess knowledge of dietary and behaviour-related determinants of non-communicable disease (NCD) of urban Senegalese women. DESIGN: A cross-sectional, population study using an interviewer-administered knowledge questionnaire, developed and validated for this study. The questionnaire consisted of 24 items with six scores measuring knowledge of: (1) diet- and behaviour-related causes of NCD; (2) diet quality-NCD relationship; (3) fruit and vegetable link with NCD; (4) health consequences of obesity; (5) causes of cardiovascular disease (CVD); and (6) causes of certain cancers. SUBJECTS: A random sample of 301 women aged 20-50 years. RESULTS: The knowledge scores developed suggest that the health consequences of obesity (mean score of 65.4%) were best understood followed by causes of CVD (mean score of 60.6%), because obesity, smoking, high blood cholesterol and dietary fat were well recognised as risk factors for CVD. Subjects scored least for their knowledge of the protective effect of fruit and vegetables (mean score of 19.9%). Knowledge of causes of certain cancers (mean score of 36.1%) was also low. Women who worked outside the home had better knowledge for two scores but otherwise no relationship was found between knowledge and literacy, formal education or body mass index. CONCLUSIONS: Findings suggest reasonable overall knowledge concerning diet and behaviour with NCD, especially given the relatively new context of the obesity epidemic in Senegal. However, there was poor knowledge of the benefit of eating fruit and vegetables and other preventable causes of certain cancers. Education targeting the benefits of vegetables and fruit may have the greatest impact on NCD prevention.  相似文献   
42.
Vegetative buds of peach (Prunus persica L. Batsch.) trees act as strong sinks and their bud break capacity can be profoundly affected by carbohydrate availability during the rest period (November-February). Analysis of xylem sap revealed seasonal changes in concentrations of sorbitol and hexoses (glucose and fructose). Sorbitol concentrations decreased and hexose concentrations increased with increasing bud break capacity. Sucrose concentration in xylem sap increased significantly but remained low. To clarify their respective roles in the early events of bud break, carbohydrate concentrations and uptake rates, and activities of NAD-dependent sorbitol dehydrogenase (SDH), sorbitol oxidase (SOX) and cell wall invertase (CWI) were determined in meristematic tissues, cushion tissues and stem segments. Only CWI activity increased in meristematic tissues shortly before bud break. In buds displaying high bud break capacity (during January and February), concentrations of sorbitol and sucrose in meristematic tissues were almost unchanged, paralleling their low rates of uptake and utilization by meristematic tissues, and indicating that sorbitol and sucrose play a negligible role in the bud break process. Hexose concentrations in meristematic tissues and glucose imported by meristematic tissues correlated positively with bud break capacity, suggesting that hexoses are involved in the early events of bud break. These findings were confirmed by data for buds that were unable to break because they had been collected from trees deprived of cold. We therefore conclude that hexoses are of greater importance than sorbitol or sucrose in the early events of bud break in peach trees.  相似文献   
43.
The aim of this review is to present an overview of the sex differentiation and sex determination processes in eels in relation to the urgent need to provide scientific knowledge to better protect and manage the Anguilla genus. Indeed, the global decline of the three main temperate eel stocks, Anguilla anguilla, Anguillidae (Fisheries Management and Ecology, 2003, 10, 365); Anguilla japonica, Anguillidae (Casselman, Eel Biology, Springer Japan, 2003, 293) and Anguilla rostrata, Anguillidae (Tatsukawa, Eel Biology, Springer, Japan, 2003, 255), raises concerns about the necessity to better understand all stages of the life cycle of eels (Righton and Walker, Journal of Fish Biology, 2013, 83, 754). Little is known about the mechanisms involved in the production of males and females in this species with environmental sex determination. Previous reviews identifying the density of individuals as the major factor influencing sex determination were undertaken (Krueger and Oliveira, Environmental Biology of Fishes, 1999, 55, 381; Reviews in Fish Biology and Fisheries, 2005, 15, 37). Here, we review the current advances on the subject, focusing on the roles of early growth rate and interindividual relationships, which are mechanisms underpinned by density, as well as the sex differentiation process, and we question how this knowledge might influence global conservation measures.  相似文献   
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45.
Bio-guided fractionation of the roots of Paris polyphylla (Trilliaceae), based on inhibition of P-glycoprotein-mediated daunorubicin efflux in K562/R7 cell line, led to isolation and identification of the three saponins 3-O-Rha(1-->2)[Ara(1-->4)]Glc-pennogenine, gracillin and polyphyllin D, and the two ecdysteroids 20-hydroxyecdysone and pinnatasterone. These compounds were tested for multidrug reversion on P-glycoprotein (ABCB1) with both drug-selected and transfected cell lines, and also on Breast Cancer Resistance Protein (BCRP/ABCG2). By contrast to a weak efficiency on BCRP, the three saponins displayed significant effects as inhibitors of P-glycoprotein-mediated drug efflux.  相似文献   
46.
The bioefficacies of essential oil and aromatized clay powder based on the mixture of clay and essential oil extracted from Clausena anisata were evaluated for their insecticidal activities and their effects on progeny production of Acanthoscelides obtectus. Contact toxicity assayed by coating on bean grains showed that these chemicals caused significant mortality of the test insect. Beetle mortality was dose dependant and after 2-day exposure the aromatized clay powder was more toxic (LD50 = 0.069 μl/g grain) than the pure essential oil (LD50 = 0.081 μl/g grain). There was, however, a highly significant loss of toxicity after 24 and 36 h following treatment with essential oil and aromatized powder, respectively. Both aromatized clay powder and pure essential oil considerably reduced the F1 progeny insect production. The essential oil evoked moderated repellent action and high fumigant toxicity (LC50 = 0.093 μl/cm3) against adults of A. obtectus. These results suggest that the clay powder could be used to stabilize the essential oil to increase its efficacy for use as an alternative to synthetic insecticides.  相似文献   
47.
In contrast to mammals and birds, fish display an amazing diversity of genetic sex determination systems, with frequent changes during evolution possibly associated with the emergence of new sex chromosomes and sex‐determining genes. To better understand the molecular and evolutionary mechanisms driving this diversity, several fish models are studied in parallel. Besides the medaka (Oryzias latipes Temminck and Schlegel, 1846) for which the master sex‐determination gene has been identified, one of the most advanced models for studying sex determination is the Southern platyfish (Xiphophorus maculatus, Günther 1966). Xiphophorus maculatus belongs to the Poeciliids, a family of live‐bearing freshwater fish, including platyfish, swordtails and guppies that perfectly illustrates the diversity of genetic sex‐determination mechanisms observed in teleosts. For X. maculatus, bacterial artificial chromosome contigs covering the sex‐determination region of the X and Y sex chromosomes have been constructed. Initial molecular analysis demonstrated that the sex‐determination region is very unstable and frequently undergoes duplications, deletions, inversions and other rearrangements. Eleven gene candidates linked to the master sex‐determining gene have been identified, some of them corresponding to pseudogenes. All putative genes are present on both the X and the Y chromosomes, suggesting a poor degree of differentiation and a young evolutionary age for platyfish sex chromosomes. When compared with other fish and tetrapod genomes, syntenies were detected only with autosomes. This observation supports an independent origin of sex chromosomes, not only in different vertebrate lineages but also between different fish species.  相似文献   
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