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121.
122.
大豆疫霉菌的EMS化学诱变 总被引:1,自引:0,他引:1
以甲基磺酸乙酯(ethylmethane sulfonate,EMS)为诱变剂,通过其对大豆疫霉菌Phytophthora sojae休止孢萌发的影响,确定化学诱变条件。通过收集单卵孢子,建立了包含640个单卵孢子系的突变体库,其中约有50%的诱变菌系在培养性状和菌落形态方面发生了明显变化,菌落形态多样,表现出较紧密或松散,近圆形或不规则;气生菌丝减少,生长速度较慢或快;在卵孢子产量方面,8.13%的菌系有增加,20.41%的菌系减少,27.82%的菌系极少或者没有卵孢子产生,43.64%的菌系卵孢子产量类似野生型。以质膜氢离子泵蛋白基因PsPMA1(plasma membrane H+-ATPase1)为对象,通过TILLING技术,从320个大豆疫霉菌突变体中获得9个突变体,进一步确认了EMS对大豆疫霉菌的诱变效果,并且估算EMS对大豆疫霉菌的诱变频率至多每115kb发生一个核苷酸变异。新构建的突变体库为开展大豆疫霉病菌的功能基因组研究奠定了遗传材料基础。 相似文献
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124.
ADRIENNE F. SUSSMAN JAMES C. HA KATHY L. BENTSON CAROLYN M. CROCKETT 《American journal of primatology》2013,75(4):303-313
Temperament differs among individuals both within and between species. Evidence suggests that differences in temperament of group members may parallel differences in social behavior among groups or between species. Here, we compared temperament between three closely related species of monkey—rhesus (Macaca mulatta), long‐tailed (M. fascicularis), and pigtailed (M. nemestrina) macaques—using cage‐front behavioral observations of individually housed monkeys at a National Primate Research Center. Frequencies of 12 behaviors in 899 subjects were analyzed using a principal components analysis to identify temperament components. The analysis identified four components, which we interpreted as Sociability toward humans, Cautiousness, Aggressiveness, and Fearfulness. Species and sexes differed in their average scores on these components, even after controlling for differences in age and early‐life experiences. Our results suggest that rhesus macaques are especially aggressive and unsociable toward humans, long‐tailed macaques are more cautious and fearful, and pigtailed macaques are more sociable toward humans and less aggressive than the other species. Pigtailed males were notably more sociable than any other group. The differences observed are consistent with reported variation in these species’ social behaviors, as rhesus macaques generally engage in more social aggression and pigtailed macaques engage in more male–male affiliative behaviors. Differences in predation risks are among the socioecological factors that might make these species‐typical behaviors adaptive. Our results suggest that adaptive species‐level social differences may be encoded in individual‐level temperaments, which are manifested even outside of a social context. Am. J. Primatol. 75:303‐313, 2013. © 2012 Wiley Periodicals, Inc. 相似文献
125.
Differences in specificity and catalytic efficiency between allozymes of esterase-4 from Drosophila mojavensis 总被引:1,自引:0,他引:1
A more than 10-fold difference in the specificity and catalytic efficiency
for 1-naphthyl esters was measured between two allozymes of esterase-4 from
Drosophila mojavensis. This difference is mainly caused by a difference in
the affinity for the 1-naphthyl esters. The amino acid compositions of the
allozymes are not significantly different, which means that the difference
in primary structure is small. Small differences in primary structure
generally do not result in such a large increase in catalytic efficiency
and such a large shift in substrate specificity as was found in the present
study.
相似文献
126.
SREE KANTHASWAMY JILLIAN NG MARIA CECILIA T. PENEDO THEA WARD DAVID GLENN SMITH JAMES C. HA 《American journal of primatology》2012,74(11):1017-1027
Pigtailed macaques (Macaca nemestrina) provide an important model for biomedical research on human disease and for studying the evolution of primate behavior. The genetic structure of captive populations of pigtailed macaques is not as well described as that of captive rhesus (M. mulatta) or cynomolgus (M. fascicularis) macaques. The Washington National Primate Research Center houses the largest captive colony of pigtailed macaques located in several different housing facilities. Based on genotypes of 18 microsatellite (short tandem repeat [STR]) loci, these pigtailed macaques are more genetically diverse than captive rhesus macaques and exhibit relatively low levels of inbreeding. Colony genetic management facilitates the maintenance of genetic variability without compromising production goals of a breeding facility. The periodic introduction of new founders from specific sources to separate housing facilities at different times influenced the colony's genetic structure over time and space markedly but did not alter its genetic diversity significantly. Changes in genetic structure over time were predominantly due to the inclusion of animals from the Yerkes National Primate Research Center in the original colony and after 2005. Strategies to equalize founder representation in the colony have maximized the representation of the founders’ genomes in the extant population. Were exchange of animals among the facilities increased, further differentiation could be avoided. The use of highly differentiated animals may confound interpretations of phenotypic differences due to the inflation of the genetic contribution to phenotypic variance of heritable traits. Am. J. Primatol. 74:1017‐1027, 2012. © 2012 Wiley Periodicals, Inc. 相似文献
127.
Voskamp KE; Noorman N; Mastebroek HA; Van Schoot NE; Den Otter CJ 《Chemical senses》1998,23(5):521-530
Spike trains from individual antennal olfactory cells of tsetse flies
(Glossina spp.) obtained during steady-state conditions (spontaneous as
well as during stimulation with 1-octen-3-ol) and dynamic stimulation with
repetitive pulses of 1-octen-3-ol were investigated by studying the spike
frequency and the temporal structure of the trains. In general, stimulation
changes the intensity of the spike activity but leaves the underlying
stochastic structure unaffected. This structure turns out to be a renewal
process. The only independently varying parameter in this process is the
mean interspike interval length, suggesting that olfactory cells of tsetse
flies may transmit information via a frequency coding. In spike records
with high firing rates, however, the stationary records had significant
negative first- order serial correlation coefficients and were non-renewal.
Some cells in this study were capable of precisely encoding the onset of
the odour pulses at frequencies up to at least 3 Hz. Cells with a rapid
return to pre-stimulus activity at the end of stimulation responded more
adequately to pulsed stimuli than cells with a long increased spike
frequency. While short-firing cells process information via a frequency
code, long-firing cells responded with two distinctive phases: a phasic,
non-renewal response and a tonic, renewal response which may function as a
memory of previous stimulations.
相似文献
128.
Cows carrying unrelated transferred embryos (ET) produced anti-leucocyte serum antibodies (aLA) more often than cows carrying their own embryos. Cows carrying the ET showed a higher frequency of cytotoxic reactions against leucocytes from 40-60 randomly chosen cows than individuals carrying their own embryos. The percentage of animals with aLA was higher in cows carrying their second or third transferred embryo than in those with their first transferred embryo. There was no change in the frequency of cytotoxic reactions with repeated pregnancies from transferred embryos. There was no difference in the toxicity of aLA in normal pregnant cows and those carrying transferred embryos. Embryonic mortality (EM) of 35, 73 and 88% was noted during pregnancies from the first, second and third successful ET, respectively. Mortality of 48% occurred in the first pregnancy following an unsuccessful ET. Embryonic mortality of 31% occurred in cows simultaneously carrying their own and a transferred embryo. A direct relationship between the presence of aLA and EM in recipients was not proved. Other fertility problems may lead to EM in cows subjected to repeated transfer of foreign embryos. 相似文献
129.
YOUNG‐JOON PARK SUJIN KIM AEREE KIM SEUNG‐YEON HA YOUNG‐MEE LEE BONG‐KYUNG SHIN HYUN‐JOO LEE SOOJIN PARK HAN‐KYEOM KIM 《Bioethics》2010,24(6):309-322
This study assessed the knowledge and perception of human biological materials (HBM) and biorepositories among three study groups in South Korea. The relationship between the knowledge and the perception among different groups was also examined by using factor and regression analyses. In a self‐reporting survey of 440 respondents, the expert group was found more likely to be knowledgeable and positively perceived than the others. Four factors emerged: Sale and Consent, Flexible Use, Self‐Confidence, and Korean Bioethics and Biosafety Action restriction perception. The results indicate that those who are well aware of the existence of biobanks were more positively inclined to receive the Sale and Consent perception. As a result of the need for high quality HBMs and the use of appropriate sampling procedures for every aspect of the collection and use process, the biorepository community should pay attention to ethical, legal, and policy issues. 相似文献
130.