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121.
The Middle Longcraig Limestone (late Visean) at Catcraig, Scotland, is densely covered with large (about 1 m in diameter) hollows, which are surrounded by numerous fossilized roots. The latter represent the positions of tree-sized plants belonging to a fossil forest. This paper aims to reconstruct its ecology based on paleosol properties, size and spatial distribution of root-casts, rooting system morphology and characteristics of coalified plant remnants. The obtained data are consistent with the supposition that the Visean peat wetland forest of Catcraig represents a Cordaitalean dominated community composed of mono-sized, most probably, even-aged giant trees. The peaty paleosol (Histosol) contains pyrite and siderite, indicating reducing and acidic conditions, whilst the abundant presence of gypsum testifies periods of elevated salinity. The adaptation of trees to such conditions is supported by morphologically evident large root mass (typically more than 1000 individual roots per cast). Good preservation of plant tissues in peat, in addition to other paleosol and rooting system characteristics allow us to conclude that the trees occupied seacoast settings or lagoons, which were not permanently flooded. 相似文献
122.
Andrey A. Parkhitko Arashdeep Singh Sharon Hsieh Yanhui Hu Richard Binari Christopher J. Lord Sridhar Hannenhalli Colm J. Ryan Norbert Perrimon 《PLoS genetics》2021,17(2)
The RB1 tumor suppressor is recurrently mutated in a variety of cancers including retinoblastomas, small cell lung cancers, triple-negative breast cancers, prostate cancers, and osteosarcomas. Finding new synthetic lethal (SL) interactions with RB1 could lead to new approaches to treating cancers with inactivated RB1. We identified 95 SL partners of RB1 based on a Drosophila screen for genetic modifiers of the eye phenotype caused by defects in the RB1 ortholog, Rbf1. We validated 38 mammalian orthologs of Rbf1 modifiers as RB1 SL partners in human cancer cell lines with defective RB1 alleles. We further show that for many of the RB1 SL genes validated in human cancer cell lines, low activity of the SL gene in human tumors, when concurrent with low levels of RB1 was associated with improved patient survival. We investigated higher order combinatorial gene interactions by creating a novel Drosophila cancer model with co-occurring Rbf1, Pten and Ras mutations, and found that targeting RB1 SL genes in this background suppressed the dramatic tumor growth and rescued fly survival whilst having minimal effects on wild-type cells. Finally, we found that drugs targeting the identified RB1 interacting genes/pathways, such as UNC3230, PYR-41, TAK-243, isoginkgetin, madrasin, and celastrol also elicit SL in human cancer cell lines. In summary, we identified several high confidence, evolutionarily conserved, novel targets for RB1-deficient cells that may be further adapted for the treatment of human cancer. 相似文献
123.
Kseniya S. Aulova Andrey A. Urusov Sergey E. Sedykh Ludmila B. Toporkova Julia A. Lopatnikova Valentina N. Buneva Sergei V. Sennikov Thomas Budde Sven G. Meuth Nelly A. Popova Irina A. Orlovskaya Georgy A. Nevinsky 《Journal of cellular and molecular medicine》2021,25(5):2493-2504
We have previously shown that immunization of C57BL/6 mice, prone to spontaneous development of experimental autoimmune encephalomyelitis (EAE), with three antigens (MOG35-55, DNA-histone complex or DNA-methylated BSA complex), alters the differentiation profiles of bone marrow haematopoietic stem cells (HSCs). These are associated with the production of autoantibodies (auto-Abs) against these antigens and the formation of abzymes hydrolysing DNA, MOG, myelin basic protein (MBP) and histones. Immunization of mice with antigens accelerates the development of EAE. This work is the first to analyse the ratio of auto-Abs without and with catalytic activities at different stages of EAE development (onset, acute and remission phases) after immunization of mice with the three specific antigens. Prior to immunization and during spontaneous in-time development of EAE, the concentration of auto-Abs against MBP, MOG, histones and DNA and activities of IgG antibodies in the hydrolysis of substrates increased in parallel; correlation coefficients = +0.69-0.94. After immunization with MOG, DNA-histone complex or DNA-met-BSA complex, both positive (from +0.13 to +0.98) and negative correlations (from −0.09 to −0.69) were found between these values. Our study is the first showing that depending on the antigen, the relative amount of harmful auto-Abs without and abzymes with low or high catalytic activities may be produced only at onset and in acute or remission phases of EAE. The antigen governs the EAE development rate, whereby the ratio of auto-Abs without catalytic activity and with enzymatic activities of harmful abzymes hydrolysing MBP, MOG, histones and DNA varies strongly between different disease phases. 相似文献
124.
Salmina Alla B. Komleva Yuliya K. Malinovskaya Nataliya A. Morgun Andrey V. Teplyashina Elena A. Lopatina Olga L. Gorina Yana V. Kharitonova Ekaterina V. Khilazheva Elena D. Shuvaev Anton N. 《Biochemistry. Biokhimii?a》2021,86(6):746-760
Biochemistry (Moscow) - Blood-brain barrier (BBB) is a structural and functional element of the neurovascular unit (NVU), which includes cells of neuronal, glial, and endothelial nature. The main... 相似文献
125.
Joyce N. Njuguna Lindsay V. Clark Kossonou G. Anzoua Larisa Bagmet Pavel Chebukin Maria S. Dwiyanti Elena Dzyubenko Nicolay Dzyubenko Bimal Kumar Ghimire Xiaoli Jin Douglas A. Johnson Uffe Jørgensen Jens Bonderup Kjeldsen Hironori Nagano Junhua Peng Karen Koefoed Petersen Andrey Sabitov Eun Soo Seong Toshihiko Yamada Ji Hye Yoo Chang Yeon Yu Hua Zhao Stephen P. Long Erik J. Sacks 《Global Change Biology Bioenergy》2023,15(5):642-662
Miscanthus is a high-yielding bioenergy crop that is broadly adapted to temperate and tropical environments. Commercial cultivation of Miscanthus is predominantly limited to a single sterile triploid clone of Miscanthus × giganteus, a hybrid between Miscanthus sacchariflorus and M. sinensis. To expand the genetic base of M. × giganteus, the substantial diversity within its progenitor species should be used for cultivar improvement and diversification. Here, we phenotyped a diversity panel of 605 M. sacchariflorus from six previously described genetic groups and 27 M. × giganteus genotypes for dry biomass yield and 16 yield-component traits, in field trials grown over 3 years at one subtropical location (Zhuji, China) and four temperate locations (Foulum, Denmark; Sapporo, Japan; Urbana, Illinois; and Chuncheon, South Korea). There was considerable diversity in yield and yield-component traits among and within genetic groups of M. sacchariflorus, and across the five locations. Biomass yield of M. sacchariflorus ranged from 0.003 to 34.0 Mg ha−1 in year 3. Variation among the genetic groups was typically greater than within, so selection of genetic group should be an important first step for breeding with M. sacchariflorus. The Yangtze 2x genetic group (=ssp. lutarioriparius) of M. sacchariflorus had the tallest and thickest culms at all locations tested. Notably, the Yangtze 2x genetic group's exceptional culm length and yield potential were driven primarily by a large number of nodes (>29 nodes culm−1 average over all locations), which was consistent with the especially late flowering of this group. The S Japan 4x, the N China/Korea/Russia 4x, and the N China 2x genetic groups were also promising genetic resources for biomass yield, culm length, and culm thickness, especially for temperate environments. Culm length was the best indicator of yield potential in M. sacchariflorus. These results will inform breeders' selection of M. sacchariflorus genotypes for population improvement and adaptation to target production environments. 相似文献
126.
da Costa Gonçalves AC Leite R Fraga-Silva RA Pinheiro SV Reis AB Reis FM Touyz RM Webb RC Alenina N Bader M Santos RA 《American journal of physiology. Heart and circulatory physiology》2007,293(4):H2588-H2596
The vasodilator/antiproliferative peptide angiotensin-(1-7) [ANG-(1-7)] is released into the corpus cavernosum sinuses, but its role in erectile function has yet to be defined. In this study, we sought to determine whether ANG-(1-7) and its receptor Mas play a role in erectile function. The ANG-(1-7) receptor Mas was immunolocalized in rat corpus cavernosum by confocal microscopy. Infusion of ANG-(1-7) into corpus cavernosum at a rate of 15.5 pmol x kg(-1) x min(-1) potentiated the elevation of the corpus cavernosum pressure induced by electrical stimulation of the major pelvic ganglion (MPG) in rats. The facilitatory effect of ANG-(1-7) was completely blunted by the specific ANG-(1-7) receptor blocker A-779 and N(omega)-nitro-L-arginine methyl ester. Nitric oxide (NO) release in the corpus cavernosum was evaluated with the fluorescent dye 4-amino-5 methylamino-2',7'-difluorofluorescein diacetate. Electrical stimulated-release of NO in rat corpus cavernosum was potentiated by ANG-(1-7). Furthermore, incubation of rat and mouse corpus cavernosum strips with ANG-(1-7) at 10 nmol/l resulted in an increase of NO release. This effect was completely abolished in mas-deficient mice. More importantly, genetic deletion of Mas resulted in compromised erectile function as demonstrated by penile fibrosis and severely depressed response to electrical stimulation of the MPG. Furthermore, the attenuated erectile function of DOCA-salt hypertensive rats was fully restored by ANG-(1-7) administration. Together these data provide strong evidence for a key role of the ANG-(1-7)-Mas axis in erectile function. 相似文献
127.
Oleinikov AV Gray MD Zhao J Montgomery DD Ghindilis AL Dill K 《Journal of proteome research》2003,2(3):313-319
Protein arrays will greatly accelerate research and development in medical and biological sciences. We have used cell-free protein biosynthesis and a parallel immobilization strategy for producing protein biochips. We demonstrate a model two-protein microarray using luciferase and green fluorescent protein, both expressed in a cell-free system and specifically immobilized on CombiMatrix semiconductor oligonucleotide microarrays. This demonstration provides evidence for the appropriate folding, activity, robust presentation, and efficient flexible detection of proteins on the microscale. 相似文献
128.
129.
Targeted deletion of AIF decreases mitochondrial oxidative phosphorylation and protects from obesity and diabetes 总被引:8,自引:0,他引:8
Pospisilik JA Knauf C Joza N Benit P Orthofer M Cani PD Ebersberger I Nakashima T Sarao R Neely G Esterbauer H Kozlov A Kahn CR Kroemer G Rustin P Burcelin R Penninger JM 《Cell》2007,131(3):476-491
Type-2 diabetes results from the development of insulin resistance and a concomitant impairment of insulin secretion. Recent studies place altered mitochondrial oxidative phosphorylation (OxPhos) as an underlying genetic element of insulin resistance. However, the causative or compensatory nature of these OxPhos changes has yet to be proven. Here, we show that muscle- and liver-specific AIF ablation in mice initiates a pattern of OxPhos deficiency closely mimicking that of human insulin resistance, and contrary to current expectations, results in increased glucose tolerance, reduced fat mass, and increased insulin sensitivity. These results are maintained upon high-fat feeding and in both genetic mosaic and ubiquitous OxPhos-deficient mutants. Importantly, the effects of AIF on glucose metabolism are acutely inducible and reversible. These findings establish that tissue-specific as well as global OxPhos defects in mice can counteract the development of insulin resistance, diabetes, and obesity. 相似文献
130.
Smirnova AS Ferreira-Silva KC Mine KL Andrade-Oliveira V Shulzhenko N Gerbase-DeLima M Morgun A 《Immunogenetics》2007,59(1):93-98
Various single nucleotide polymorphisms (SNPs) have been investigated regarding association with gene expression levels or
human diseases. Although different SNPs within one gene are frequently analyzed individually, it is highly probable that in
the majority of the cases, a precise combination of SNP alleles, i.e., haplotype, determines a functional trait. Methods commonly
used for haplotype determination, involving studies in families, cloning, or somatic cell hybrids, are expensive and time-consuming.
We herein suggest a novel and simple strategy for haplotype determination, involving selective haplotype depletion with a
restriction enzyme, followed by sequencing. We studied 11 LTA gene polymorphisms in 102 Brazilian individuals, and we applied this novel methodology for haplotyping 67 out of 70 LTA heterozygous individuals. We concluded that the method is rapid and efficient, and, as it includes only simple and widespread-used
techniques, it could be used in most of the laboratories without further investment in equipments. The wider usage of haplotyping
could be important to clarify contradictory results frequently observed among studies that focus on a single SNP.
Maria Gerbase-DeLima and Andrey Morgun are co-senior authors. 相似文献