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ROK JING OH 《Ecological Entomology》1979,4(4):345-353
Abstract. 1. Mating of the brown planthopper, Nilaparvata lugens , was investigated in relation to oviposition. Females became unreceptive immediately after mating and showed various types of repelling behaviour to courting males. As a result, females usually did not mate repeatedly in quick succession, but after ceasing to lay fertilized eggs they behaved as virgins and mated again before producing more fertilized eggs.
2. Copulation, followed by deposition of fertilized eggs, occurred twice, or in a few cases three times, throughout the adult stage. Copulation lasted about 2 min at the first mating and about 1 min at the second or third mating.
3. When the number of fertilized eggs began to decrease rapidly, oviposition rate also decreased, but it increased again immediately after re-mating. Repeated copulation was also related to the potential rate of population increase. In the present experiments, the estimates of net reproductive rate ( R0 ) in brachypterous females was 287.7 (first mating), 88.3 (second mating) and 7.2 (third mating) and in macropterous females 286.8, 120.6 and 3.6 respectively.
4. In a patchy environment, repeated copulation following an invasion may contribute to the increase of a population. 相似文献
2. Copulation, followed by deposition of fertilized eggs, occurred twice, or in a few cases three times, throughout the adult stage. Copulation lasted about 2 min at the first mating and about 1 min at the second or third mating.
3. When the number of fertilized eggs began to decrease rapidly, oviposition rate also decreased, but it increased again immediately after re-mating. Repeated copulation was also related to the potential rate of population increase. In the present experiments, the estimates of net reproductive rate ( R
4. In a patchy environment, repeated copulation following an invasion may contribute to the increase of a population. 相似文献
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Stacey L. Lance Jesús E. Maldonado Carol I. Bocetti O.H. Pattee Jonathan D. Ballou Robert C. Fleischer 《Conservation Genetics》2003,4(6):707-718
The Delmarva fox squirrel, Sciurus niger cinereus, is a federally listed endangered subspecies whose range has been reduced by 90%. In an attempt to increase both population
size and range, translocation sites were established beginning in the 1960's by moving squirrels from the natural range to
sites outside the current range. Although translocations have served as the primary component of the DFS recovery program,
there has been very little post-release examination of the genetics of the translocation sites. In this study, we developed
ten microsatellite loci, screened the three polymorphic loci, and sequenced a 330 bp fragment of the mitochondrial control
region in order to assess levels of genetic variation in natural and translocated regions of Delmarva fox squirrels and to
compare them to Southeastern fox squirrels (S. n. niger). Although we found low levels of microsatellite polymorphism, there were no differences in heterozygosity between natural
and translocated regions, or between Delmarva and Southeastern fox squirrels. We found high levels of polymorphism in the
mitochondrial control region. Our patterns of haplotype diversity suggest incomplete lineage sorting of the two subspecies.
In general, our data suggest that the current levels of genetic variation in the translocated sites are representative of
those found in the natural population, and we encourage the continued use of translocations as a major component of Delmarva
fox squirrel recovery.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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Archives of Microbiology - 相似文献
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Early Reproductive Ontogeny in Interspecific Crosses of Arachis hypogaea and Section Arachis Species
Wild Arachis species have been recognized as sources of resistanceto pests and pathogens that infect A. hypogaea L. and causesubstantial yield losses. However, utilization of these geneticresources for crop improvement has been difficult. This studywas conducted to (a) understand the processes of early embryogrowth and development in four Arachis species, two A. hypogaeacultivars and their hybrids and (b) identify parental compatibilitiesin reciprocal crosses of A. hypogaea. The results indicatedthat delayed fertilization beyond 24 h, coupled with slow proembryogrowth, leads to embryo abortion in many interspecific crosses.For example, in female A. cardenasii crosses, lack of or delayedfertilization leads to failure to obtain hybrids. When A. batizocoiwas used as a female parent, delayed fertilization and the inabilityof quiescent proembryos to resume growth after soil penetrationcaused abortion. Embryos of A. hypogaea x A. glandulifera crossesdeveloped normally during the first 21 d after fertilization,but then aborted at a later time. In this study, A. hypogaeawas always a better female parent than the wild Arachis species.Increasing the number of pollinations per cross, using the cultivatedspecies as the female parent, utilizing different A. hypogaeavarieties, and embryo rescue techniques are suggested to improvethe probability of obtaining interspecific hybrids in Arachis.Copyright1995, 1999 Academic Press Peanut, interspecific hybrids, Arachis, wild species, incompatibilities 相似文献