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991.
An hydroponic culture was conducted to investigate the effect of saline stress on the essential oil and fatty acid composition
of Tunisian coriander (Coriandrum sativum L.) roots. Ten days old coriander seedlings were treated during 3 weeks with different NaCl concentrations (0, 25, 50 and
75 mM). Roots volatile components and fatty acids were analyzed. The essential oil yield was 0.06% in the control, on the
basis of dry matter weight, and did not changed at low concentration (25 mM), while it increased significantly with increasing
NaCl concentrations to reach 0.12 and 0.21% at 50 and 75 mM NaCl, respectively. The major volatile component was (E)-2-dodecenal with 52% of total essential oil constituents, followed by decanal, dodecanal, (E)-2-tridecenal and (E)-2-dodecenal. Further, the amount of these compounds was affected differently by the NaCl level. Total fatty acid amount
of coriander roots increased significantly only with 50 and 75 mM NaCl. Three major fatty acids: linoleic (43%), oleic (25.5%)
and palmitic (21.6%) were identified. Linoleic acid amount remains unchanged at 25 mM, while it increased with raising NaCl
concentrations. However, oleic acid amount decreased only at 25 mM and no effect was observed at 50 and 75 mM. Fatty acid
percentages were differently affected by salt. The oleic/linoleic ratio was reduced with raising NaCl concentrations. 相似文献
992.
Bettina Maccagnani Francesca Giacomello Marco Fanti Davide Gobbin Stefano Maini Gino Angeli 《BioControl》2009,54(1):123-133
The efficiency of two pollinators, Apis mellifera L. (Hymenoptera: Apidae) and the mason bee Osmia cornuta (Latreille) (Hymenoptera: Megachilidae), as carriers of biocontrol agents (BCA) from flower to flower (secondary colonisation) was investigated on apple cv ‘Golden Delicious’. The BCA tested was Bacillus subtilis, strain BD170 (Biopro®) developed for the control of the ‘fire blight’ caused by Erwinia amylovora (Burril) Winslow et al. The two insect species were studied as secondary BCA carriers on apple plants in pots under net screened tunnels. Their behaviour and capacity to deposit the BCA in the most receptive flower parts were compared both by washing, diluting and plating the flower organs on a recovery medium and by means of PCR analyses based on a molecular marker. O. cornuta showed better performances with respect to A. mellifera. For the field trials, pollinators were introduced in four apple orchards. During apple’s flowering, the BD170 (100 g hl?l) was sprayed once in two fields, and twice in the others. The pollinators’ efficacy in carrying the BCA from sprayed flowers to the stigmas of newly opened ones at different times after the spray treatment was evaluated. The detection of the BCA was performed by PCR analysis. The percentages of positive PCR flower samples were higher in the internal treated areas of the fields with respect to the external untreated ones, but the high colonisation level found in the latter and in the flowers opened in both areas several days after the treatment(s) demonstrated that pollinators can play an important role as secondary carriers. 相似文献
993.
Caberg JH Hubert P Herman L Herfs M Roncarati P Boniver J Delvenne P 《Cancer immunology, immunotherapy : CII》2009,58(1):39-47
Human papillomavirus (HPV) infection, particularly type 16, is causally associated with cancer of the uterine cervix. The
persistence or progression of cervical lesions suggests that viral antigens are not adequately presented to the immune system.
This hypothesis is reinforced by the observation that most squamous intraepithelial lesions (SILs) show quantitative and functional
alterations of Langerhans cells (LC). The infiltration of immature LC in the squamous epithelium is mainly controlled by Macrophage
Inflammatory Protein 3α/CCL20. After having shown that CCL20 production is altered in HPV-transformed keratinocytes (KC),
the possible role of HPV16 E6 and E7 viral oncoproteins in the reduced CCL20 levels observed in SILs was investigated by silencing
HPV16 E6 and E7 oncogenes by RNA interference (siRNA). This treatment not only increased CCL20 secretion but also resulted
in the modulation of NF-κB p50, p52 and p65 precursor localization. Moreover, silencing of E6 and E7 oncogenes in HPV16-transformed
KC induced a significantly higher migratory capacity of LC in a Boyden chamber assay and in an in vitro formed (pre)neoplastic
epithelium reminiscent of high-grade SILs. Anti-CCL20 neutralizing antibody experiments showed that the increased migration
of LC is due to the re-expression of CCL20 in E6 and E7 siRNA transfected KC. These data suggest that HPV16 E6/E7-induced
down-regulation of CCL20 observed during the cervical carcinogenesis may contribute to a diminished capacity of the immune
system to control HPV infection.
P. Hubert and J. H. Caberg contributed equally to this work. 相似文献
994.
One of the biggest challenges facing evolutionary biologists is to identify and understand loci that explain fitness variation
in natural populations. This review describes how genetic (linkage) mapping with single nucleotide polymorphism (SNP) markers
can lead to great progress in this area. Strategies for SNP discovery and SNP genotyping are described and an overview of
how to model SNP genotype information in mapping studies is presented. Finally, the opportunity afforded by new generation
sequencing and typing technologies to map fitness genes by genome-wide association studies is discussed. 相似文献
995.
Soltani F Mosaffa F Iranshahi M Karimi G Malekaneh M Haghighi F Behravan J 《Cell biology and toxicology》2009,25(3):291-296
The protective properties of a prenylated coumarin, umbelliprenin (UMB), on the human lymphocytes DNA lesions were tested.
Lymphocytes were isolated from blood samples taken from healthy volunteers. DNA breaks and resistance to H2O2-induced damage were measured using a single-cell microgel electrophoresis technique under alkaline conditions (comet assay).
Human lymphocytes were incubated in UMB (10, 25, 50, 100, 200, and 400 μM) alone or a combination of different concentrations
of UMB (10, 25, 50, 100, 200, and 400 μM) and 25 μM H2O2. Untreated cells, ascorbic acid (AA; 25, 50, 100, 200, and 400 μM) and H2O2 (25 μM) were considered as negative control, positive control, and the standard antioxidant agent for our study, respectively.
Single cells were analyzed with “TriTek Cometscore version 1.5” software. The DNA damage was expressed as percent tail DNA.
UMB exhibited a concentration-dependent increase in protection activity against DNA damage induced by 25 μM H2O2 (from 67.28% to 39.17%). The antigenotoxic activity of AA, in the range 0–50 μM, was greater than that of UMB. However, no
significant difference (p > 0.05) in the protective activity was found between UMB and AA at concentrations of approximately higher than 50 μM. 相似文献
996.
Artificial cross between two genetically different populations of Japanese Misgurnus loach was made to examine the reproductive capacity of the artificial inter-populational hybrid females. Ploidy status and
microsatellite genotypes of the eggs laid by these hybrids were inferred from those determined in progenies developed by normal
fertilization with haploid loach sperm, induced gynogenesis with UV-irradiated goldfish sperm and/or hybridization with intact
goldfish sperm. Some hybrid females laid unreduced diploid eggs genetically identical to the mother. However, these diploid
eggs could not develop by spontaneous gynogenesis, but grow to triploid by incorporation of a sperm nucleus. Other hybrid
females laid haploid eggs together with diploid eggs and/or various aneuploid and polyploid eggs. Thus, a disruption of normal
meiosis occurred in inter-populational hybrid females. The results suggested that the two populations should be so distant
as to give rise to atypical formation of unreduced and other unusual eggs in their hybrids. 相似文献
997.
Christine Driller Dyah Perwitasari-Farajallah Hans Zischler Stefan Merker 《International journal of primatology》2009,30(2):267-281
Previous sociobiological studies of tarsiers were invariably based on field observations. Sulawesi tarsiers are known for
monogamous or facultative polygynous social mating systems, but, to date, no data exist to describe the genetic mating system.
We here bring together behavioral studies and molecular tools for the first time to elucidate mating behavior and kinship
within a tarsier population. We investigated the social system of the recently described Tarsius lariang, which researchers have never studied before. Between September and November 2005, we conducted field observations and sampling
in central Sulawesi, Indonesia, where this species is endemic. Ten of 11 social groups of the focal population were composed
of 1 adult male, 1 adult female, and putative offspring. To enlighten genetic relationships, we used 12 microsatellite loci
and mitochondrial DNA sequences of 26 captured and sampled Lariang tarsiers for parentage and relatedness analyses. A significant
number of young were the offspring of the sampled group adults, suggesting a predominantly monogamous social and genetic mating
system. There is evidence for extrapair young in groups in which adult pairs exhibit close relationships, leading to the assumption
that extrapair mating is solicited to avoid inbreeding. Ten of 11 social groups lived in monogamous social systems, indicating
monogamy to be the rule in Tarsius lariang. 相似文献
998.
Kieran G. Meade Fernando Narciandi Sarah Cahalane Carla Reiman Brenda Allan Cliona O’Farrelly 《Immunogenetics》2009,61(2):101-110
Salmonella typhimurium and Campylobacter jejuni pose significant risks to human health and poultry are a major vector for infection. Comparative in vivo infection models were performed to compare the avian host immune response to both bacterial species. Forty-five commercial
broiler chickens were orally challenged with either C. jejuni or S. typhimurium whilst 60 similar control birds were mock challenged in parallel. Birds were sacrificed at 0, 6, 20 and 48 h post-infection
and cloacal swabs, blood and tissue samples taken. Peripheral blood leukocytes were isolated for flow cytometric analyses
and RNA was extracted for gene expression profiling. Colonisation patterns were markedly different between the two bacterial
species, with systemic colonisation of Campylobacter outside the gastrointestinal tract. Salmonella infection induced significant
changes in circulating heterophil and monocyte/macrophage populations, whilst Campylobacter infection had no effect on the
heterophil numbers but caused a significant early increase in circulating monocytes/macrophages. Toll-like receptor 1 (TLR1) gene expression was decreased, and avian β-defensin (AvBD) gene expression (AvBD3, AvBD10 and AvBD12) was significantly increased in response to Salmonella infection (P < 0.05). In contrast, Campylobacter infection induced increased TLR21 gene expression but significantly reduced expression of seven antimicrobial peptide (AMP) genes (AvBD3, AvBD4, AvBD8, AvBD13, AvBD14, CTHL2 and CTHL3; P < 0.05). Considered together, microbiological, cellular and gene expression profiles indicate that the innate immune system
responds differently to Salmonella and to Campylobacter infection. Furthermore, reduction in the expression of AMPs may play
a role in the persistence of high level colonisation of the host by Campylobacter.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
999.
The paper couples the results obtained by applying the expert and the rapid Macrophyte Quality Indices set up to assess the
ecological status of the Italian transitional environments according to the requirements by the Water Framework Directive
(2000/60/CE). The indices were validated by comparing the composition of the macrophyte assemblages and the values of some
bio-physico-chemical parameters of the water column of 20 stations of the Venice lagoon sampled monthly for one year between
2003 and 2005. In 5 stations out of the 20, the ones which fall within the 5 classes of ecological status suggested by the
Water Framework Directive, sedimentation rates, sediment grain-size, and nutrient and pollutant (metals, Polychloro-Dibenzo-Dioxins/Furans,
Polycyclic Aromatic Hydrocarbons, Pesticides and Polychlorinated Biphenils) concentrations in surface sediments were also
determined. Results showed strong relationships between the trends of these environmental parameters and the composition and
structure of macrophyte associations, as well as with the Macrophyte Quality Index assessment. Chlorophyceae showed a trend
opposite to Rhodophyceae whose presence was concentrated in oxygenated and transparent environments. Chlorophyceae and the
species characterised by low scores prevailed in turbid areas where nutrient and pollutant concentrations were high. Results
allowed the identification of the conditions of the “reference sites” (confinement areas and sites with high water renewal)
and the integration of the dichotomic key used for the application of the R-MaQI.
Handling editor: S. M. Thomaz 相似文献
1000.
Predation is a strong selective force with both direct and indirect effects on an animal’s fitness. In order to increase the chances of survival, animals have developed different antipredator strategies. However, these strategies have associated costs, so animals should assess their actual risk of predation and shape their antipredator effort accordingly. Under a stressful situation, such as the presence of predators, animals display a physiological stress response that might be proportional to the risk perceived. We tested this hypothesis in wild European rabbits (Oryctolagus cuniculus), subjected to different predator pressures, in Doñana National Park (Spain). We measured the concentrations of fecal corticosterone metabolites (FCM) in 20 rabbit populations. By means of track censuses we obtained indexes of mammalian predator presence for each rabbit population. Other factors that could modify the physiological stress response, such as breeding status, food availability and rabbit density, were also considered. Model selection based on information theory showed that predator pressure was the main factor triggering the glucocorticoid release and that the physiological stress response was positively correlated with the indexes of the presence of mammalian carnivore predators. Other factors, such as food availability and density of rabbits, were considerably less important. We conclude that rabbits are able to assess their actual risk of predation and show a threat-sensitive physiological response. 相似文献