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421.
Tamsin K. Saxton Catherine Steel Katie Rowley Amy V. Newman Thom Baguley 《Evolution and human behavior》2017,38(4):429-433
Research on optimal outbreeding describes the greater reproductive success experienced on average by couples who are neither too closely related, nor too genetically dissimilar. How is optimal outbreeding achieved? Faces that subtly resemble family members could present useful cues to a potential reproductive partner with an optimal level of genetic dissimilarity. Here, we present the first empirical data that heterosexual women select partners who resemble their brothers. Raters ranked the facial similarity between a woman's male partner, and that woman's brother compared to foils. In a multilevel ordinal logistic regression that modeled variability in both the stimuli and the raters, there was clear evidence for perceptual similarity in facial photographs of a woman's partner and her brother. That is, although siblings themselves are sexually aversive, sibling resemblance is not. The affective responses of disgust and attraction may be calibrated to distinguish close kin from individuals with some genetic dissimilarity during partner choice. 相似文献
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Background
Pelodera (Rhabditis) strongyloides is a small saprophytic nematode that lives in decaying organic matter. On rare occasions, it can invade the mammalian skin, causing a pruritic, erythematous, alopecic and crusting dermatitis on skin sites that come into contact with the ground. Diagnosis of the disease is based on case history (a dog living outdoors on damp straw bedding) with characteristic skin lesions and on the demonstration of typical larvae in skin scrapings or biopsy. Pelodera (rhabditic) dermatitis cases have been reported mainly from Central European countries and the United States. 相似文献424.
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Kinesin heavy chain is essential for viability and neuromuscular functions in Drosophila, but mutants show no defects in mitosis. 总被引:26,自引:0,他引:26
The in vivo function of the microtubule motor protein kinesin was examined in Drosophila using genetics and immunolocalization. Kinesin heavy chain mutations (khc) cause abnormal behavior and lethality. Mutant larvae exhibit loss of mobility and tactile responsiveness in the most posterior segments, followed by general paralysis and death during larval or pupal development. Adults homozygous for a temperature-sensitive allele also exhibit a loss in mobility and sensory responses. The data indicate that kinesin function is essential and suggest that kinesin has an important role in the neuromuscular system, perhaps as a motor for axonal transport. The possibility of more general cellular functions remains open, but observation of embryogenesis and morphogenesis in khc mutants suggests that mitosis and the cell cycle can proceed in spite of impaired kinesin function. Immunolocalization suggests that kinesin may have some general cellular functions but that it is not a major component of mitotic spindles. 相似文献
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D. R. Panthee V. R. Pantalone A. M. Saxton D. R. West C. E. Sams 《Molecular breeding : new strategies in plant improvement》2006,17(1):79-89
Soybean [Glycine max (L.) Merr.] is the single largest source of protein in animal feed. However, few studies have been conducted to evaluate
genomic regions controlling amino acid composition in soybean. It is important to study the genetics of amino acid composition
to achieve improvements through breeding. The objectives of this study were to determine the ratios between essential to non-essential
(E:NE) and essential to total (E:T) amino acids, and to identify genomic regions controlling essential and non-essential amino
acid composition in soybean seed. To achieve these objectives, 101 F6-derived recombinant inbred lines (RIL) developed from a cross of N87-984-16 × TN93-99 were used. Ground soybean seed samples
were analyzed for amino acids using a near infrared spectroscopy (NIRS) instrument. A significant (p < 0.01) difference among the RIL was found for amino acid composition. Heritability estimates on an entry mean basis ranged
from 0.13 for His to 0.67 for Tyr. A total of 94 polymorphic simple sequence repeat (SSR) molecular genetic markers were screened
in DNA from progenies. Single factor ANOVA was used to identify candidate quantitative trait loci (QTL), which were then confirmed
by QTL Cartographer. At least one QTL for each amino acid was detected in this population. QTL linked to molecular markers
Satt143, Satt168, Satt203, Satt274 and Satt495 were associated with most of the amino acids. Phenotypic variation explained
by an individual QTL ranged from 9.4 to 45.3%. QTL detected for amino acids in soybean in this experiment are expected to
be useful for future breeding programs targeting development of improved soybean amino acid composition for human and animal
nutrition. 相似文献