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991.
Osler disease is an autosomal dominant disorder of the fibrovascular tissue characterized by arteriovenous malformations with multi-systemic haemorrhages. Recurrent epistaxis is the predominant symptom in more than 90% of patients. Recent studies showed circadian and seasonal patterns in the onset of nosebleeds, similar to acute cardiovascular events, such as myocardial infarction and stroke. The aim of this study was to determine whether such patterns would also apply to the onset of epistaxis in patients with Osler disease. In all, 110 patients with Osler disease who were under treatment for recurrent epistaxis at the University Hospital of Mannheim were requested to complete a questionnaire addressing the intensity and frequency of epistaxis according to the classification of Bergler et al., as well as circadian and circannual rhythmicity in the occurrence of epistaxis according to visual analogue scales (VAS). More than half of the patients claimed to experience daily to weekly episodes of recurrent epistaxis. The occurrence of epistaxis showed a biphasic 24 h pattern, with a primary peak in the morning (05:00-8:00 h) and smaller secondary peaks in the evening (17:00-20:00 h and 21:00-00:00 h). No significant seasonal variation was found in the onset of epistaxis. However, a slight tendency, with a peak in winter months, was observed. Similar to other chronobiological studies on nosebleeds, this study showed that the 24 h pattern and seasonal tendency in the onset of epistaxis even applied to patients with Osler disease. Further investigations are necessary to determine the pathological mechanism underlying this phenomenon. 相似文献
992.
Uluoglu C Durakoglugil DB Karasu C Ozbey G Gunes A Zengil H 《Chronobiology international》2007,24(6):1081-1094
The aim of this study was to investigate whether time-dependent variations in the relaxant effect of acetylcholine, an endothelium-dependent vasorelaxant via muscarinic receptors, and isoprenaline, a nonselective β-adrenoceptor agonist in rat aorta, are influenced by streptozotocin (STZ)-induced experimental diabetes. Adult male rats were divided randomly into two groups: control and STZ-induced (STZ, 55 mg/kg, intraperitoneal) diabetes. The animals were synchronized to a 12:12 h light-dark cycle (lights on 08:00 h) and sacrificed at six different times of day (1, 5, 9, 13, 17, and 21 hours after lights on; HALO) eight weeks after STZ injection. The in vitro responsiveness of thoracic aorta rings obtained from control and diabetic rats to acetylcholine (10-9-10-5 M) and isoprenaline (10-10-10-3 M) was determined in six different times. EC50 (the concentration inducing half of the maximum response) values and maximum responses were calculated from cumulative concentration-response curves of the agonists and were analyzed with respect to time and STZ treatment. Treatment, time, and interactions between treatment and time were tested by two-way analysis of variance (ANOVA). To analyze differences due to biological time, one-way ANOVA was used. STZ treatment did not significantly change EC50 values or maximum responses for both agonists. There were statistically significant time-dependent variations in the EC50 values for isoprenaline and maximum responses for both acetylcholine and isoprenaline in control groups by one-way ANOVA, but significant time-dependent variations disappeared in the aortas isolated from STZ-induced diabetic rats. The vasodilator responses to acetylcholine and isoprenaline failed to show any significant interaction (treatment×time of study) between STZ treatment and time of sacrifice in both EC50 values and maximum responses by two-way ANOVA. These results indicate there is a basic temporal pattern in the responses to acetylcholine and isoprenaline in rat aorta which continues in diabetes. It is shown for the first time that experimental diabetes does not change the 24 h pattern of responses to acetylcholine and isoprenaline, and that time-dependent variations in the responses to these agonists disappear in diabetic animals. Although further studies are required to define the underlying mechanism(s) of these findings, results suggest that experimental diabetes can modify the time-dependent vasorelaxant responses of rat aorta. This may help to understand the circadian rhythms in cardiovascular physiology and pathology or in drug effects in diabetes. 相似文献
993.
994.
We have conducted a preliminary study of tidal and diurnal variations in the distribution of dominant larval and juvenile
fishes in the Chikugo River inlet (Ariake Bay, Kyushu, Japan) to determine whether selective tidal stream transport (STST)
occurs. Larval and juvenile fish were collected from the mesohaline zone of the Chikugo River inlet during spring 2002. Temperature,
salinity, depth, and current velocity were measured. Larval and juvenile abundance were compared among four tidal conditions,
flooding tide, high tide, ebbing tide, and low tide, and between day and night. A total of 12 families, 15 species, and 5,577
individuals were collected. Temperature did not vary significantly with tidal conditions whereas salinity, depth, and current
velocity varied significantly. Salinity also was correlated significantly and positively with depth. The abundance of most
of the fishes was correlated positively and significantly with salinity and depth. Lateolabrax japonicus, Trachidermus fasciatus, Acanthogobius hasta, and other gobiid larvae (Gobiidae spp.) were significantly more abundant during high tide; in contrast, Coilia nasus and Neosalanx reganius were most abundant during low tide. The abundance of most of the fishes was higher during high tides at night than during
the day, indicating the existence of STST, which may be strategically associated with ascending progress to upstream nursery
areas. 相似文献
995.
The 235-kDa antigenic rhoptry protein Py235 of Plasmodium yoelii is encoded by a large, highly polymorphic gene family. Monoclonal antibodies to some of these antigens have been shown to attenuate the virulence of the lethal YM strain of the parasite, converting a potentially fatal YM infection to a fulminating one typical of the nonlethal 17X strain, by inducing a switch in target cell preference from mature red blood cells to reticulocytes. The reason for this is not known but would suggest that antigenic determinants of Py235 may be useful in or as subunit vaccines. To identify such determinants, we constructed an epitope expression library of one Py235 variant and screened the library with the antibodies. Thus, we mapped 5- and 12-amino acid epitopes to the C-terminus of the antigen. Both epitopes were more reactive with protective than with nonprotective monoclonal antibodies. This may explain the differential protection conferred by these antibodies upon their passive transfer into mice. 相似文献
996.
The Internal Transcribed Spacer (ITS) regions of ribosomal DNA are widely used as markers for phylogenetic analyses and environmental
sampling from a variety of organisms including fungi, plants, and animals. In theory, concerted evolution homogenizes multicopy
genes so that little or no variation exists within populations or individuals. However, contrary to theory, ITS variation
has been confirmed in populations and individuals from a diverse range of eukaryotes. The presence of intraspecific and intra-individual
variation in multicopy genes has important implications for ecological and phylogenetic studies, yet relatively little is
known about natural variation of these genes, particularly at the community level. In this study, we examined intraspecific
and intra-sporocarp ITS variation by DNA sequencing from sporocarps and pooled roots from 68 species of ectomycorrhizal fungi
collected at a single site in a Quercus woodland. We detected ITS variation in 27 species, roughly 40% of the taxa examined. Although intraspecific ITS variation
was generally low (0.16–2.85%, mean = 0.74%), it was widespread within this fungal community. We detected ITS variation in
both sporocarps and ectomycorrhizal roots, and variation was present within species of Ascomycota and Basidiomycota, two distantly
related lineages within the Fungi. We discuss the implications of such widespread ITS variability with special reference to
DNA-based environmental sampling from diverse fungal communities.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
997.
Growth rate of the Kuruma prawn, Marsupenaeus japonicus is an important economic trait, with larger animals commanding higher market prices. To identify gene markers associated
with growth, a genetic map of a full-sib F2 intercross family of M. japonicus has previously been generated and quantitative trait loci (QTL) influencing weight, total length, and carapace length were
identified. In this study, amplified fragment length polymorphism (AFLP) markers associated with the major QTL region, contributing
16% to phenotypic variation, were characterized. Flanking sequence has been obtained and allelic variants responsible for
segregation patterns of these markers have been identified. The genomic sequence surrounding the AFLP band 7.21a, residing
under the QTL peak, contains a gene sequence homologous to the elongation of very long chain fatty acids-like (ELOVL) protein family. A full-length mRNA (ELOVL-MJ) encoding this protein was isolated from M. japonicus, representing both the first ELOVL gene in crustacea and the first candidate gene identified via QTL studies in crustacea. 相似文献
998.
Leuko S Goh F Allen MA Burns BP Walter MR Neilan BA 《Extremophiles : life under extreme conditions》2007,11(1):203-210
Hamelin Pool in Western Australia is one of the two major sites in the world with active marine stromatolite formation. Surrounded
by living smooth and pustular mats, these ancient laminated structures are associated with cyanobacterial communities. Recent
studies have identified a wide diversity of bacteria and archaea in this habitat. By understanding and evaluating the microbial
diversity of this environment we can obtain insights into the formation of early life on Earth, as stromatolites have been
dated in the geological record as far back as 3.5 billion years. Automated ribosomal intergenic spacer analysis (ARISA) patterns
were shown to be a useful method to genetically discriminate halophilic archaea within this environment. Patterns of known
halophilic archaea are consistent, by replicate analysis, and the halophilic strains isolated from stromatolites have novel
intergenic spacer profiles. ARISA–PCR, performed directly on extracted DNA from different sample sites, provided significant
insights into the extent of previous unknown diversity of halophilic archaea within this environment. Cloning and sequence
analysis of the spacer regions obtained from stromatolites confirmed the novel and broad diversity of halophilic archaea in
this environment. 相似文献
999.
1000.