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241.
Wu Zeng Eduardo A. Undurraga Colleen Nyberg Dan T.A. Eisenberg Sabita Parida Ariela Zycherman Oyunbileg Magvanjav Victoria Reyes-García Susan Tanner Ricardo Godoy 《Economics & Human Biology》2013,11(3):391-400
Sibling configuration, including birth order, or the number, age, and sex of siblings is associated with parental resource allocation between children and is thus associated with a person's well-being. Little is known about the association between specific types of siblings and adult health outcomes. Here we test several hypotheses about sibling composition (number of older brothers, older sisters, younger sisters, younger brothers) and adult blood pressure in a foraging-farming society of native Amazonians in Bolivia (Tsimane’). We collected data in 2007 from 374 adults (16–60 years of age) from 196 households in 13 villages. Household random-effects multiple regressions were run using systolic (SBP) or diastolic blood pressure (DBP) as outcomes; covariates included the four sibling categories and control variables (e.g., sex, age, education, body mass index [BMI]). Mean SBP and DBP were 114 (SD = 14) and 66 (SD = 11) mmHg. The prevalence of hypertension was 5.08%. Having an additional younger brother bore a small (3.3–5.9%) positive association with both SBP and DBP, with the effect weakening as people aged. Having an additional younger sister was associated with a small (3.8%) increase in SBP among women, with the magnitude shrinking as people aged. In a large family, the number of younger brothers may exert an impact on an individual's blood pressure. 相似文献
242.
Heterojunction Solar Cells: Remarkably High Conversion Efficiency of Inverted Bulk Heterojunction Solar Cells: From Ultrafast Laser Spectroscopy and Electron Microscopy to Device Fabrication and Optimization (Adv. Energy Mater. 11/2016) 下载免费PDF全文
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Plants have adapted to different environmental niches by fine-tuning the developmental factors working together to regulate traits. Variations in the developmental factors result in a wide range of quantitative variations in these traits that helped plants survive better. The major developmental pathways affecting plant architecture are also under the control of such pathways. Most notable are the CLAVATA-WUSCHEL pathway regulating shoot apical meristem fate, GID1-DELLA module influencing plant height and tillering, LAZY1-TAC1 module controlling branch/tiller angle and the TFL1-FT determining the floral fate in plants. Allelic variants of these key regulators selected during domestication shaped the crops the way we know them today. There is immense yield potential in the ‘ideal plant architecture’ of a crop. With the available genome-editing techniques, possibilities are not restricted to naturally occurring variations. Using a transient reprogramming system, one can screen the effect of several developmental gene expressions in novel ecosystems to identify the best targets. We can use the plant's fine-tuning mechanism for customizing crops to specific environments. The process of crop domestication can be accelerated with a proper understanding of these developmental pathways. It is time to step forward towards the next-generation molecular breeding for restructuring plant types in crops ensuring yield stability. 相似文献
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Phenotypic variability for abdominal pigmentation in females of an Indian natural population ofDrosophila melanogaster was studied using isofemale lines and by rearing the larvae and pupae at 4 different temperatures ranging from 20–30°C. The
dark pigmented area was found to increase in all the three segments when the growth temperature decreases. A significant positive
correlation was detected for the occurrence of dark pigmentation in the 5th and 6th segments in each growth temperature but
for other comparisons the correlation was not regular. Analysis of variance (ANOVA) was carried out both for individual segments
over different growth temperatures and also for each temperature over the three abdominal segments and in all cases found
to be statistically significant. The results are quite different from the earlier observation in FrenchDrosophila melanogaster and suggest that genes controlling pigmentation are temperature dependent; temperature could affect post-transitional events
involved in pigmentation. The present findings also clearly indicate that significant genotype-environment interaction exists,
responsible for the production of desired phenotype at the opportune moment during the life span of a species. 相似文献
248.
M. Sethi V. Mohanty S. Mishra J. Dash S. Mahapatra D. Parida A.P. Mohapatra R. Mishra P. Prasad A. Parida S. Senapati 《Letters in applied microbiology》2022,74(4):577-585
Antibiotic resistance is a major public health concern worldwide. The gut microbiota harbours multiple antibiotic resistant genes (ARGs) that contribute to the existing and future microbial population in a community or ecosystem. This study aimed to investigate the prevalence of 35 antibiotic resistance genes (ARGs) in the gut microbiota of the tribal people of Nabarangpur, Odisha, India. A total of 83 faecal samples were collected from three different tribes (Bhatra, Gond, and Paraja). Total faecal DNA was extracted, and the simplex polymerase chain reaction was performed to detect selected ARGs. Further analysis was done to estimate the incidence of these ARGs across these tribes based on alcohol consumption habits. We identified a higher prevalence of tetracycline resistance genes (tetW, tetQ and tetM) in the gut microbiota among three populations. Furthermore, a significant (P = 0·024) difference in ARG prevalence against vancomycin in individuals with and without alcohol consumption habits was noticed. The overall distribution of ARGs among the three major tribes of this location was found to be very similar. Together, irrespective of the tribes, the people of this location have gut microbiota harbouring different kinds of ARGs and tetracycline-resistant genes are the most commonly found ARGs. 相似文献
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Jitender Giri Swarup K. Parida Saurabh Raghuvanshi Akhilesh K. Tyagi 《Current Genomics》2021,22(1):16
Rice occupies a pre-eminent position as a food crop in the world. Its production, how- ever, entails up to 3000 liters of water per kilogram of grain produced. Such high demand makes rice prone to drought easily. Sustainable rice cultivation with limited water resources requires the deployment of a suitable strategy for better water use efficiency and improved drought tolerance. Several drought-related genes have been evaluated in rice for their mode of action in conferring drought tolerance. Manipulation of components of abscisic acid signal transduction, stomatal density, deposition of cuticular wax, and protein modification pathways are emerging as priority targets. Gene reprogramming by microRNAs is also being explored to achieve drought tolerance. Genetically dissected Quantitative Trait Loci (QTLs) and their constituent genes are being deployed to develop drought-tolerant rice varieties. Progressive research and challenges include a better understanding of crucial components of drought response and search for new targets and the deployment of improved varieties in the field. 相似文献