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901.
We developed eight PCR?primer pairs of polymorphic microsatellite loci for the túngara frog Physalaemus pustulosus. Genomic libraries were enriched for one of four microsatellite repeat sequences (CAn, GAn, ATGn and TAGAn). Following characterization of microsatellite loci by sequencing, primers were designed and PCR conditions optimized. Microsatellite PCR‐amplification was tested in 37 frogs from 8 populations in Costa Rica and Panama. Primer sequences, PCR conditions, allelelic diversities and observed as well as expected heterozygosities in the screened populations are described. 相似文献
902.
903.
M. E. Lucero W. Mueller J. Hubstenberger G. C. Phillips M. A. O’Connell 《In vitro cellular & developmental biology. Plant》1999,35(6):480-486
Summary Cell suspension cultures of Datura innoxia were incubated in the presence of the nitro-substituted explosives 2,4,6-trinitrotoluene (TNT), 1,3,5-trinitro-1,3,5-triazine
(RDX), and 1,3,5,7-tetranitro-1,3,5,7-tetraazocyclooctane (HMX). Cellular tolerance levels and TNT biotransformation kinetics
were examined. Tolerance to TNT varied as cell suspensions aged. Concentrations of RDX or HMX in excess of reported solubility
limits produced no observable changes in cell viability. GC/MS analysis of TNT-treated cell media and cell lysates revealed
rapid removal of TNT. Within 12 h, less than 1% of the initial TNT remained in the growth medium. Aminodinitrotoluenes (ADNTs),
known metabolites of TNT, accumulated transiently in cell lysates, and to a lesser extent in cell media. ADNT concentrations
started to decrease after 3 h. After 12 h, less than 5% of the initial TNT could be detected as ADNT. Total ADNTs never exceeded
26% of initial TNT, suggesting that additional biotransformation steps also occurred. No other nitroaromatics were detected.
A pseudo-first order rate constant for TNT clearance was calculated, k=0.40 h−1. D. innoxia cell suspension cultures demonstrated virtually complete clearance of TNT and of subsequent ADNT metabolites in less than
12 h. This rapid metabolism of nitroaromatics by the Datura cell suspension system indicates the utility of this system for further molecular and biochemical studies. 相似文献
904.
A gene for autosomal recessive symmetrical spastic cerebral palsy maps to chromosome 2q24-25.
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D P McHale S Mitchell S Bundey L Moynihan D A Campbell C G Woods N J Lench R F Mueller A F Markham 《American journal of human genetics》1999,64(2):526-532
Cerebral palsy has an incidence of approximately 1/500 births, although this varies between different ethnic groups. Genetic forms of the disease account for approximately 1%-2% of cases in most countries but contribute a larger proportion in populations with extensive inbreeding. We have clinically characterized consanguineous families with multiple children affected by symmetrical spastic cerebral palsy, to locate recessive genes responsible for this condition. The eight families studied were identified from databases of patients in different regions of the United Kingdom. After ascertainment and clinical assessment, we performed a genomewide search for linkage, using 290 polymorphic DNA markers. In three families, a region of homozygosity at chromosome 2q24-q25 was identified between the markers D2S124 and D2S148. The largest family gave a maximum LOD score of 3.0, by multipoint analysis (HOMOZ). The maximum combined multipoint LOD score for the three families was 5.75. The minimum region of homozygosity is approximately 5 cM between the markers D2S124 and D2S2284. We have shown that a proportion of autosomal recessive symmetrical spastic cerebral palsy maps to chromosome 2q24-25. The identification of genes involved in the etiology of cerebral palsy may lead to improved management of this clinically intractable condition. 相似文献
905.
Ranjan Deka Mark D. Shriver Ling Mei Yu Elisa Mueller Heidreich Li Jin Yixi Zhong Stephen T. Mcgarvey Shyam Swarup Agarwal Clareann H. Bunker Tetsuro Miki Joachim Hundrieser Shih-Jiun Yin Salmo Raskin Ramiro Barrantes Robert E. Ferrell Ranajit Chakraborty 《Journal of genetics》1999,78(2):99-121
We have analysed genetic variation at 23 microsatellite loci in a global sample of 16 ethnically and geographically diverse
human populations. On the basis of their ancestral heritage and geographic locations, the studied populations can be divided
into five major groups, viz. African, Caucasian, Asian Mongoloid, American Indian and Pacific Islander. With respect to the
distribution of alleles at the 23 loci, large variability exists among the examined populations. However, with the exception
of the American Indians and the Pacific Islanders, populations within a continental group show a greater degree of similarity.
Phylogenetic analyses based on allele frequencies at the examined loci show that the first split of the present-day human
populations had occurred between the Africans and all of the non-African populations, lending support to an African origin
of modern human populations. Gene diversity analyses show that the coefficient of gene diversity estimated from the 23 loci
is, in general, larger for populations that have remained isolated and probably of smaller effective sizes, such as the American
Indians and the Pacific Islanders. These analyses also demonstrate that the component of total gene diversity, which is attributed
to variation between groups of populations, is significantly larger than that among populations within each group. The empirical
data presented in this work and their analyses reaffirm that evolutionary histories and the extent of genetic variation among
human populations can be studied using microsatellite loci. 相似文献
906.
Myo T. Naung Elijah Martin Jacob Munro Somya Mehra Andrew J. Guy Moses Laman G. L. Abby Harrison Livingstone Tavul Manuel Hetzel Dominic Kwiatkowski Ivo Mueller Melanie Bahlo Alyssa E. Barry 《PLoS computational biology》2022,18(2)
Investigation of the diversity of malaria parasite antigens can help prioritize and validate them as vaccine candidates and identify the most common variants for inclusion in vaccine formulations. Studies of vaccine candidates of the most virulent human malaria parasite, Plasmodium falciparum, have focused on a handful of well-known antigens, while several others have never been studied. Here we examine the global diversity and population structure of leading vaccine candidate antigens of P. falciparum using the MalariaGEN Pf3K (version 5.1) resource, comprising more than 2600 genomes from 15 malaria endemic countries. A stringent variant calling pipeline was used to extract high quality antigen gene ‘haplotypes’ from the global dataset and a new R-package named VaxPack was used to streamline population genetic analyses. In addition, a newly developed algorithm that enables spatial averaging of selection pressure on 3D protein structures was applied to the dataset. We analysed the genes encoding 23 leading and novel candidate malaria vaccine antigens including csp, trap, eba175, ama1, rh5, and CelTOS. Our analysis shows that current malaria vaccine formulations are based on rare haplotypes and thus may have limited efficacy against natural parasite populations. High levels of diversity with evidence of balancing selection was detected for most of the erythrocytic and pre-erythrocytic antigens. Measures of natural selection were then mapped to 3D protein structures to predict targets of functional antibodies. For some antigens, geographical variation in the intensity and distribution of these signals on the 3D structure suggests adaptation to different human host or mosquito vector populations. This study provides an essential framework for the diversity of P. falciparum antigens to be considered in the design of the next generation of malaria vaccines. 相似文献
907.
908.
909.
Hyung Chul Kim Timothy J. Wallington Sherry A. Mueller Bert Bras Tina Guldberg Francisco Tejada 《Journal of Industrial Ecology》2016,20(5):1122-1133
Literature data for vehicle life cycle water consumption are limited and contradictory; there are no published estimates of vehicle life cycle water withdrawal. To place future discussions of sustainable mobility on a firmer technical basis, we report the results of a cradle‐to‐grave assessment of water withdrawal and water consumption for the gasoline internal combustion engine vehicle (ICEV) and battery electric vehicle (BEV) variants of the 2012 Ford Focus. U.S. average life cycle water withdrawal and consumption of 531 and 131 cubic meters (m3), respectively, for a lifetime driving distance of 160,000 miles are estimated for the Focus ICEV using E10 gasoline. Employing our upper bound of water use in oil refinery operations and corn and ethanol production increases the life cycle withdrawal and consumption to 1,570 and 761 m3, respectively. The U.S. average life cycle water withdrawal for the Focus BEV is 3,770 m3 (7 times that for the ICEV, reflecting the large volume of cooling water required during electricity generation), whereas the water consumption is 170 m3 (comparable to that for the ICEV). Vehicle use is the most significant phase of the life cycle with fuel production, accounting for 49% of water withdrawal and 82% of water consumption for the ICEV. For the BEV, fuel (electricity) production accounts for 92% of life cycle water withdrawal and 85% of consumption. The results highlight the importance of renewable and sustainable fuels and increased vehicle energy efficiency in providing sustainable mobility. 相似文献
910.
Light exposure leads to reorganization of microglomeruli in the mushroom bodies and influences juvenile hormone levels in the honeybee
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Christina Scholl Ying Wang Markus Krischke Martin J. Mueller Gro V. Amdam Wolfgang Rössler 《Developmental neurobiology》2014,74(11):1141-1153
Honeybees show a remarkable behavioral plasticity at the transition from nursing inside the hive to foraging for nectar and/or pollen outside. This plasticity is important for age‐related division of labor in honeybee colonies. The behavioral transition is associated with significant volume and synaptic changes in the mushroom bodies (MBs), brain centers for sensory integration, learning, and memory. We tested whether precocious sensory exposure to light leads to changes in the density of synaptic complexes [microglomeruli (MG)] in the MBs. The results show that exposure to light pulses over 3 days induces a significant decrease in the MG density in visual subregions (collar) of the MB. Earlier studies had shown that foragers have increased levels of juvenile hormone (JH) co‐occurring with a decrease of vitellogenin (Vg). Previous work further established that RNAi‐mediated knockdown of vg and ultraspiracle (usp) induced an upregulation of JH levels, which can lead to precocious foraging. By disturbing both Vg and JH pathways using gene knockdown of vg and usp, we tested whether the changes in the hormonal system directly affect MG densities. Our study shows that MG numbers remained unchanged when Vg and JH pathways were perturbed, suggesting no direct hormonal influences on MG densities. However, mass spectrometry detection of JH revealed that precocious light exposure triggered an increase in JH levels in the hemolymph (HL) of young bees. This suggests a dual effect following light exposure via direct effects on MG reorganization in the MB calyx and a possible positive feedback on HL JH levels. © 2014 Wiley Periodicals, Inc. Develop Neurobiol 74: 1141–1153, 2014 相似文献