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181.
I. Amaral G. J. de Moraes C. C. Melville D. J. Andrade 《Experimental & applied acarology》2018,74(4):395-402
Brevipalpus yothersi Baker (Acari: Tenuipalpidae) was recently confirmed as one of the main vectors of citrus leprosis. Knowledge about this mite’s biology is essential to understand its population dynamics, in order to solve management issues in citrus orchards and explain why citrus leprosis is more severe in some regions. This paper aimed to study biological factors affecting prevailing population levels of B. yothersi and incidence of citrus leprosis. Mites were sampled from orchards in the south, north and northwestern regions of São Paulo State, Brazil. We assessed duration of the developmental stages, oviposition, incubation period, egg viability, longevity, net reproductive rate (Ro), mean generation time (T), intrinsic rate of increase (rm) and finite rate of increase (λ). There were small differences in parameter values between the three populations. Our results indicated that the various measures adopted in the control of the three populations did not lead to major biological differences between populations for the evaluated parameters. 相似文献
182.
Silvana V. Amaral Giovana G. Ribeiro Mário J. Müller Victor H. Valiati Ana Leal-Zanchet 《Organisms Diversity & Evolution》2018,18(1):87-99
The genus Imbira Carbayo et al., 2013 encompasses two species, Imbira guaiana (Leal-Zanchet & Carbayo, 2001) and Imbira marcusi Carbayo et al., 2013, which occur in south Brazil, in areas originally covered by the Atlantic Forest. In the present study, we examine the genetic diversity within the genus, investigate the occurrence of molecular autapomorphies for its species and describe a new species for the genus based on an integrative approach. The Bayesian and maximum likelihood analyses based on DNA barcoding recovered the monophyly of the genus Imbira, but indicate that specimens representing I. marcusi correspond to five distinct lineages. These analyses, as well as sequence divergence data, revealed that the new species herein described is closely related to I. guaiana and that the specific status of specimens of I. marcusi available in GenBank should be reviewed. In addition, sequence analysis revealed 32 molecular autapomorphies for all independent evolutionary units within the genus. The new species described herein seems to be endemic to its type locality, a private area without legal protection. 相似文献
183.
Ari P. Araujo-Neto Hygor Ferreira-Fernandes Carolina M.M. Amaral Lina G. Santos Ant?nio C. Freitas Jacinto C. Silva-Neto Juan A. Rey Rommel R. Burbano Benedito B. da Silva France K.N. Yoshioka Giovanny R. Pinto 《Genetics and molecular biology》2016,39(1):24-29
Prostate cancer is the second most common cancer among men in western populations, and despite its high mortality, its etiology remains unknown. Inflammatory processes are related to the etiology of various types of tumors, and prostate inflammation, in particular, has been associated with prostate cancer carcinogenesis and progression. Human papillomavirus (HPV) is associated with benign and malignant lesions in the anogenital tract of both females and males. The possible role of HPV in prostate carcinogenesis is a subject of great controversy. In this study, we aimed to examine the prevalence of HPV infections in prostate carcinomas of patients from northeastern Brazil. This study included 104 tissue samples from primary prostate carcinoma cases. HPV DNA was purified and then amplified using MY09/11 and GP5+/GP6+ degenerate primer sets that detect a wide range of HPV types, and with specific PCR primers sets for E6 and E7 HPV regions to detect HPV 16. None of the samples showed amplification products of HPV DNA for primer sets MY09/11 and GP5+/GP6+, or the specific primer set for the E6 and E7 HPV regions. HPV infection, thus, does not seem to be one of the causes of prostate cancer in the population studied. 相似文献
184.
185.
Nara F. Nascimento Jasmin A. Hicks Karen N. Carlson Aikaterini Hatzidis Danielle N. Amaral 《Biological Rhythm Research》2016,47(1):133-143
Chronobiological disruptions, including shift work, have been linked to a number of disorders such as fatigue and diabetes. Additionally, there is evidence to support that exercise cannot only counteract fatigue and the onset of diabetes, but also alleviate the other negative symptoms associated with shift work. Therefore, the present study investigated the effects of wheel running and monthly 6-h phase advances on the circadian locomotor activity patterns and glucose and insulin levels in C57BL6/J mice. 6-h phase advances produced decreases in fasting glucose and increases in insulin, and wheel-running was able to alleviate the spike in insulin secretion. Additionally, mice experiencing the shift increased their food intake, despite having no change in body mass. Circadian wheel-running activity was also altered in phase-advanced mice. These results provide further evidence that chronobiological disruptions can lead to alterations in physiology and behavior, and that exercise can alleviate some of those symptoms. 相似文献
186.
André dos Santos Bragança Gil Climbiê Ferreira Hall Volker Bittrich Maria do Carmo Estanislau do Amaral 《Nordic Journal of Botany》2016,34(5):559-564
A new species of Neomarica from the Brazilian Atlantic Forest is described and illustrated. Neomarica sergipensis A. Gil & M.C.E. Amaral sp. nov. (Trimezieae, Iridoideae, Iridaceae) grows in restinga forests (forests on the coastal plains dominated by sandy soils) in the state of Sergipe, northeastern Brazil. The new species resembles Neomarica northiana, especially due to the white flowers with the basal third of the tepals yellow and covered by brown maculae, but differs by the inner tepals of with the center of the apical third is tinted violet to purple, yellow stigmatic crests with fimbriate to erose margins, and the endemic occurrence in Sergipe. 相似文献
187.
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189.
Lia Queiroz do Amaral 《Human Evolution》1989,4(1):33-44
Hindrances against bipedalism evolution are localized in obstetrical constraints, maternal mortality rates, infant birth trauma
and unsafe pregnancy. Analysis of infant survival probability shows that a shift to bipedalism could occur as a necessary
consequence of the process of body fur reduction, in a balance between such hindrances and safe infant transportation. Fur
reduction is proposed to correlate with cooling mechanism in intra-species physical fights. The triggering of a feed-back
mechanism connecting reduction of body fur to canine reduction would be responsible for a passage from threat displays to
actual physical fights. The proposed scenario for such changes is the transition from uni-male to multi-male social structures
among Hominoidea. The implications of the approach adopted are discussed. 相似文献
190.
European Working Group on CF Genetics 《Human genetics》1990,85(4):436-445
Summary In this collaborative European study, a total of 4871 cystic fibrosis (CF) chromosomes and 3539 normal chromosomes have been
characterized for the haplotypes defined by the 2 extragenic polymorphic sequences revealed by XV2c and KM19. The association
between one of these haplotypes (B haplotype) and the most frequent CF mutation, ΔF508, suggests for the latter a single origin
and a subsequent diffusion according to a South East-North West gradient. The linkage disequilibrium data between CF and the
B haplotype in different European populations are compatible with a relatively more recent appearance of the mutation in Northern
Europe whereas in Southern Europe a longer history of the same mutation would have allowed time for recombination with other
haplotypes. This model is also compatible with a selective advantage of carriers but does not account for (1) the excess of
B haplotypes observed among both normal and non-ΔF508 CF chromosomes; (2) the correlation between the B haplotype and the
severity of the phenotypic effect caused by CF mutations, as measured by pancreatic insufficiency and meconium ileus. 相似文献