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121.
Lisa Timmons Hayley LunaJordan Martinez Zachary MooreVaishnavi Nagarajan Juliana Metichecchia KemegeNadeem Asad 《FEBS letters》2014
Rare Caenorhabditis elegans males arise when sex chromosome non-disjunction occurs during meiosis in self-fertilizing hermaphrodites. Non-disjunction is a relatively rare event, and males are typically observed at a frequency of less than one in five hundred wild-type animals. Males are required for genetic crosses and phenotypic analysis, yet current methods to generate large numbers of males can be cumbersome. Here, we identify RNAi reagents (dsRNA-expressing bacteria) with improved effectiveness for eliciting males. Specifically, we used RNAi to systematically reduce the expression of over two hundred genes with meiotic chromosome segregation functions, and we identified a set of RNAi reagents that robustly and reproducibly elicited male progeny. 相似文献
122.
Jianchang Zhou Paul C. Dimayuga Xiaoning Zhao Juliana YanoWai Man Lio Portia TrinidadTomoyuki Honjo Bojan CercekPrediman K. Shah Kuang-Yuh Chyu 《Biochemical and biophysical research communications》2014
Background
It is increasingly evident that CD8+ T cells are involved in atherosclerosis but the specific subtypes have yet to be defined. CD8+CD25+ T cells exert suppressive effects on immune signaling and modulate experimental autoimmune disorders but their role in atherosclerosis remains to be determined. The phenotype and functional role of CD8+CD25+ T cells in experimental atherosclerosis were investigated in this study.Methods and results
CD8+CD25+ T cells were observed in atherosclerotic plaques of apoE(−/−) mice fed hypercholesterolemic diet. Characterization by flow cytometric analysis and functional evaluation using a CFSE-based proliferation assays revealed a suppressive phenotype and function of splenic CD8+CD25+ T cells from apoE(−/−) mice. Depletion of CD8+CD25+ from total CD8+ T cells rendered higher cytolytic activity of the remaining CD8+CD25− T cells. Adoptive transfer of CD8+CD25+ T cells into apoE(−/−) mice suppressed the proliferation of splenic CD4+ T cells and significantly reduced atherosclerosis in recipient mice.Conclusions
Our study has identified an athero-protective role for CD8+CD25+ T cells in experimental atherosclerosis. 相似文献123.
Tadashi Ikegami Akira Honda Teruo Miyazaki Motoyuki Kohjima Makoto Nakamuta Yasushi Matsuzaki 《Biochemical and biophysical research communications》2014
Oxidative stress and dysregulated cholesterol metabolism are characteristic features of chronic hepatitis C virus infection (CHC). Therefore, we analyzed serum oxysterol profiles in CHC patients and examined the significance of oxysterols in CHC. The concentrations of 7α-hydroxycholesterol, 4β-hydroxycholesterol and 25-hydroxycholesterol as determined by LC–ESI–MS/MS were significantly elevated by +236%, +29% and +44%, respectively, in CHC patients compared with controls. Moreover, the elevated levels were significantly decreased by anti-viral therapy using PEGylated-interferon and ribavirin for 3 months. In contrast, 24S-hydroxycholesterol, 27-hydroxycholesterol and 7α-hydroxy-4-cholesten-3-one concentrations were not affected by CHC or anti-viral treatment. These results suggest that some oxysterols that are elevated in CHC are produced by cholesterol autoxidation due to oxidative stress or inflammation in the liver. Oxysterols may represent novel targets for the inhibition of disease progression and the prevention of hepatocarcinogenesis in CHC patients. 相似文献
124.
Franciscanas Pontoporia blainvillei are small dolphins endemic to Brazil, Uruguay and Argentina. During routine pathologic examinations, chronic pneumonia associated with cholesterol deposits was found in 16.7% of stranded and incidentally bycaught franciscanas (n = 60), and was more frequent in dolphins from the Brazilian state of S?o Paulo (Franciscana Management Area II) and frequently accompanied by splenic lymphoid hyperplasia. It is unclear why these otherwise uncommon lesions were relatively frequent in the studied dolphins, and further research is advised. 相似文献
125.
Camila B. Piantino Juliana M. Sousa-Canavez Victor Srougi Fernanda Salvadori Raphael Kato Pedro Paulo R. Ayres Miguel Srougi Luiz Heraldo Camara-Lopes Gilka Jorge Figaro Gattás Cintia Fridman Fernanda de Toledo Isaque Santana Kátia Ramos Moreira Leite 《In vitro cellular & developmental biology. Animal》2010,46(2):131-139
Bladder cancer (BC) is the fourth most common cancer in the USA. In Brazil, BC represents 3% of the total existing carcinomas in the population and represents the second highest incidence among urological tumors. The majority of bladder cancer cell lines available were derived from Caucasians and established in the seventies or eighties. Thus, neoplasia development in these cells likely occurred in environment conditions vastly different than today. In the present study, we report the establishment and characterization of three Brazilian bladder cancer cell lines (BexBra1, BexBra2, and BexBra4). These cell lines may be helpful for dissecting the genetic and epigenetic aspects that trigger the progression of BC. Moreover, the development of a Brazilian representative of the disease will allow us to investigate the potential inter-racial differences of malignancy-associated phenotypes in bladder cancer. 相似文献
126.
Eder Jorge de Oliveira Vanusia Batista Oliveira Amorim Edneide Luciana Santiago Matos Juliana Leles Costa Milene da Silva Castellen Juliano Gomes Pádua Jorge Luiz Loyola Dantas 《Plant Molecular Biology Reporter》2010,28(3):519-530
A set of 81 new microsatellite markers for Carica papaya L. previously identified by data mining using freely available sequence information from Genbank were tested for polymorphism
using 30 germplasm accessions from the Papaya Germplasm Bank (PGM) at Embrapa Mandioca e Fruticultura Tropical (CNPMF) and
18 landraces. The data were used to estimate pairwise genetic distances between the genotypes. A neighbor-joining based dendrogram
was used to define clusters and infer possible genetic structuring of the collection. Most microsatellites were polymorphic
(73%), with an observed number of alleles per locus ranging from one to eleven. The levels of observed and expected heterozygosity
for 51 polymorphic loci varied from 0.00 to 0.85 and from 0.08 to 0.82, averaging 0.19 and 0.59, respectively. Forty-four
percent of microsatellites showed polymorphism information content (PIC) higher than 0.50. The compound microsatellites seem
to be more informative than dinucleotide and trinucleotide repeats in average alleles per locus and PIC. Among dinucleotides,
AG/TC or GA/CT repeat motifs exhibited more informativeness than TA/AT, GT/CA and TG/AC repeat motifs. The neighbor-joining
analysis based on shared allele distance could differentiate all the papaya accessions and landraces as well as differences
in their genetic structure. This set of markers will be useful for examining parentage, inbreeding and population structure
in papaya. 相似文献
127.
Åke Lindström Juliana Dänhardt Martin Green Raymond H. G. Klaassen Peter Olsson 《Journal of avian biology》2010,41(2):154-162
Today's intensive farming practices are known to have affected farmland biodiversity negatively in many different ways. As far as birds are concerned, they are known to have suffered during both summer and winter. Relatively little is known about the effects on birds during migration. We studied the stopover ecology of the Eurasian golden plover Pluvialis apricaria, a species listed in EU Birds Directive, in intensively farmed arable land in southernmost Sweden in the autumns of 2003–2007. We used key ecological variables (length of stay, fat deposition and moult) as fitness proxies to evaluate how the birds manage in this habitat. Eurasian golden plovers were present in large numbers mainly on arable fields from early August to November and radio‐tagged birds were found to stay in the area for up to three months. Adult birds carried out a substantial part of their flight feather moult during their stay. Body mass increased only somewhat during moult, but from the last stages of moult and onwards fuel loads corresponding to 24% above lean body mass (LBM) were accumulated at a rate of 0.5% of LBM per day, before the birds departed. Juveniles arrived later, from mid Sep., and had a similar pattern of fuel deposition. The fact that the birds choose to stay for long periods, moult in the area, and manage to store substantial fuel loads strongly suggests that Eurasian golden plovers do well in this intensively farmed arable land. 相似文献
128.
Diane L. Marshall Anna P. Tyler Nathan J. Abrahamson Joy J. Avritt Melanie G. Barnes Leah L. Larkin Juliana S. Medeiros Jerusha Reynolds Marieken G. M. Shaner Heather L. Simpson Satya Maliakal-Witt 《Sexual plant reproduction》2010,23(4):325-336
Although increases in atmospheric [CO2] are known to affect plant physiology, growth and reproduction, understanding of these effects is limited because most studies of reproductive consequences focus solely on female function. Therefore, we examined the effects of CO2 enrichment on male function in the annual Raphanus sativus. Pollen donors grown under elevated [CO2] initially sired a higher proportion of seeds per fruit than ambient [CO2]-grown plants when each was tested against two different standard competitors; however, by the end of the 5-month experiment, these pollen donors sired fewer seeds than ambient [CO2]-grown plants and produced a lower proportion of viable pollen grains. The results of this experiment confirm that elevated [CO2] can alter reproductive success. Additionally, the change in response to elevated [CO2] over time varied among pollen donor families; thus, changes in [CO2] could act as a selective force on this species. 相似文献
129.
Andréia S Lessa Bruno D Paredes Juliana V Dias Adriana B Carvalho Luiz Fernando Quintanilha Christina M Takiya Bernardo R Tura Guilherme FM Rezende Antonio C Campos de Carvalho Célia MC Resende Regina CS Goldenberg 《BMC veterinary research》2010,6(1):1-10
Background
Atypical scrapie was first identified in Norwegian sheep in 1998 and has subsequently been identified in many countries. Retrospective studies have identified cases predating the initial identification of this form of scrapie, and epidemiological studies have indicated that it does not conform to the behaviour of an infectious disease, giving rise to the hypothesis that it represents spontaneous disease. However, atypical scrapie isolates have been shown to be infectious experimentally, through intracerebral inoculation in transgenic mice and sheep. The first successful challenge of a sheep with 'field' atypical scrapie from an homologous donor sheep was reported in 2007.Results
This study demonstrates that atypical scrapie has distinct clinical, pathological and biochemical characteristics which are maintained on transmission and sub-passage, and which are distinct from other strains of transmissible spongiform encephalopathies in the same host genotype.Conclusions
Atypical scrapie is consistently transmissible within AHQ homozygous sheep, and the disease phenotype is preserved on sub-passage. 相似文献130.