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21.
Summary Two protocols for clonal propagation of kurrat (Allium ampeloprasum var.kurrat) using explants from the basal plates of mature plants are described. In direct formation, explants were cultured in Murashige and Skoog (MS) medium and supplemented with either benzyladenine at 0.0 or 4.4 μM, or supplemented with 7.0 μM benzyladenine and 0.1 μM naphthaleneacetic acid. Shoots appeared after 4 wk of culture. In the two-step procedure, explants were cultured first on MS medium supplemented with 1.4 μM 2,4-dichlorophenoxyacetic acid and 1.4 μM kinetin, and incubated in the dark for 4 wk. They were then transferred to MS medium supplemented with 4.4 μM benzyladenine for shoot formation. All shoots were rooted on MS medium containing 5 g·liter−1 activated charcoal. Normal viable plants were successfully established in soil.  相似文献   
22.
Molecular Biology Reports - Autism spectrum disorder (ASD) is an increasing concern among the Iraqi Arab population. The genetic alterations that cause ASD are likely to converge at the synapse....  相似文献   
23.

Background

Current Aedes aegypti larval control methods are often insufficient for preventing dengue epidemics. To improve control efficiency and cost-effectiveness, some advocate eliminating or treating only highly productive containers. The population-level outcome of this strategy, however, will depend on details of Ae. aegypti oviposition behavior.

Methodology/Principal Findings

We simultaneously monitored female oviposition and juvenile development in 80 experimental containers located across 20 houses in Iquitos, Peru, to test the hypothesis that Ae. aegypti oviposit preferentially in sites with the greatest potential for maximizing offspring fitness. Females consistently laid more eggs in large vs. small containers (β = 9.18, p<0.001), and in unmanaged vs. manually filled containers (β = 5.33, p<0.001). Using microsatellites to track the development of immature Ae. aegypti, we found a negative correlation between oviposition preference and pupation probability (β = −3.37, p<0.001). Body size of emerging adults was also negatively associated with the preferred oviposition site characteristics of large size (females: β = −0.19, p<0.001; males: β = −0.11, p = 0.002) and non-management (females: β = −0.17, p<0.001; males: β = −0.11, p<0.001). Inside a semi-field enclosure, we simulated a container elimination campaign targeting the most productive oviposition sites. Compared to the two post-intervention trials, egg batches were more clumped during the first pre-intervention trial (β = −0.17, P<0.001), but not the second (β = 0.01, p = 0.900). Overall, when preferred containers were unavailable, the probability that any given container received eggs increased (β = 1.36, p<0.001).

Conclusions/Significance

Ae. aegypti oviposition site choice can contribute to population regulation by limiting the production and size of adults. Targeted larval control strategies may unintentionally lead to dispersion of eggs among suitable, but previously unoccupied or under-utilized containers. We recommend integrating targeted larval control measures with other strategies that leverage selective oviposition behavior, such as luring ovipositing females to gravid traps or egg sinks.  相似文献   
24.
Summary A procedure is described to regenerate shoots and plants from the embryonic axis of avocado seedlings with benzyladenine or thidiazuron. Explants were grown in the dark for 10 d and then transferred to an 18-h photoperiod to induce multiple shoots. Increased concentrations of benzyladenine or thidiazuron resulted in increased shoot production. Shoots were transferred to shoot promoting media where additional shoots were formed. Under the best conditions, six rooted shoots were produced per original explant. About 80% of the shoots with roots survived in the glasshouse and produced normal phenotypic plants.  相似文献   
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