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61.
Kirsten Skamstrup Hansen Stefan Vieths Helle Vestergaard Per Stahl Skov Carsten Bindslev-Jensen Lars K. Poulsen 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2001,756(1-2)
The aim of the study was to investigate the possibility of a seasonal variation in reactivity to apples in 27 birch pollen allergic patients. Before and during the birch pollen season 1998, the patients were subjected to double-blind, placebo-controlled food challenges (DBPCFCs) with grated fresh Golden Delicious apple followed by an open food challenge with whole fresh apple. The clinical reactions elicited during the challenges were evaluated both by the patients and the investigators. Moreover, the skin reactivity and the in vitro reactivity to apple were evaluated by skin prick test (SPT), leukocyte histamine release (HR), measurement of specific IgE, and immunoblotting experiments. The sensitivity of the DBPCFC, when compared with the result of the open challenge, was 0.74 (14/19) before the season and 0.80 (16/20) during the season. None of the patients reacted to the blinded challenge without a subsequent reaction to the open challenge. One placebo reaction was registered both before and in season, but not in the same patient. The patient scores of the first positive challenges, and the maximal scores of each combined blinded and open challenge session, were significantly increased during the pollen season (P<0.05). The scores of the open challenge were significantly higher than the scores of the DBPCFC both before the season and during the in-season challenges (P<0.05). Specific IgE against Golden Delicious increased during season (P<0.05), while neither SPT, HR, nor immunoblotting experiments could confirm an increase in reactivity. In conclusion, the results of the oral challenge tests indicated an increase in clinical reactivity to apples during the birch pollen season in birch pollen allergic individuals. 相似文献
62.
Christian C. Voigt Linn S. Lehnert Ana G. Popa-Lisseanu Mateusz Ciechanowski Péter Estók Florian Gloza-Rausch Tamás Görföl Matthias Göttsche Carsten Harrje Meike Hötzel Tobias Teige Reiner Wohlgemuth Stephanie Kramer-Schadt 《Biodiversity and Conservation》2014,23(3):617-631
Many European migratory bat species hibernate in large hollow trees, a decreasing resource in present day silviculture. Here, we report on the importance of man-made hibernacula to support trans-boundary populations of noctule bats (Nyctalus noctula), a species that performs seasonal long distance movements throughout Europe. In winter, we surveyed nine bat roosts (eight artificial and one natural) in Germany and collected small tufts of fur from a total of 608 individuals. We then measured the stable isotope ratios of the non-exchangeable hydrogen in fur keratin and estimated the origin of migrants using a refined isoscape origin model that included information on expected flight distances and migration directions. According to the stable isotope signature, 78 % of hibernating bats originated from local populations. The remaining 22 % of hibernacula occupants originated from distant populations, mostly from places in northern or eastern countries such as Sweden, Poland and Baltic countries. Our results confirm that many noctule bats cross one or several political borders during migration. Data on the breeding origin of hibernating noctule bats also suggest that artificial roosts may not only be important for local but also for distant populations. Protection of natural and artificial hibernacula in managed forests may support the trans-boundary populations of migratory bats when hollow trees are scarce in managed forests. 相似文献
63.
Karina Tuz Ruxandra Bachmann-Gagescu Diana?R. O’Day Kiet Hua Christine?R. Isabella Ian?G. Phelps Allan?E. Stolarski Brian?J. O’Roak Jennifer?C. Dempsey Charles Lourenco Abdulrahman Alswaid Carsten?G. B?nnemann Livija Medne Sheela Nampoothiri Zornitza Stark Richard?J. Leventer Meral Top?u Ali Cansu Sujatha Jagadeesh Stephen Done Gisele?E. Ishak Ian?A. Glass Jay Shendure Stephan?C.F. Neuhauss Chad?R. Haldeman-Englert Dan Doherty Russell?J. Ferland 《American journal of human genetics》2014,94(1):62-72
Joubert syndrome (JBTS) is a recessive ciliopathy in which a subset of affected individuals also have the skeletal dysplasia Jeune asphyxiating thoracic dystrophy (JATD). Here, we have identified biallelic truncating CSPP1 (centrosome and spindle pole associated protein 1) mutations in 19 JBTS-affected individuals, four of whom also have features of JATD. CSPP1 mutations explain ∼5% of JBTS in our cohort, and despite truncating mutations in all affected individuals, the range of phenotypic severity is broad. Morpholino knockdown of cspp1 in zebrafish caused phenotypes reported in other zebrafish models of JBTS (curved body shape, pronephric cysts, and cerebellar abnormalities) and reduced ciliary localization of Arl13b, further supporting loss of CSPP1 function as a cause of JBTS. Fibroblasts from affected individuals with CSPP1 mutations showed reduced numbers of primary cilia and/or short primary cilia, as well as reduced axonemal localization of ciliary proteins ARL13B and adenylyl cyclase III. In summary, CSPP1 mutations are a major cause of the Joubert-Jeune phenotype in humans; however, the mechanism by which these mutations lead to both JBTS and JATD remains unknown. 相似文献
64.
Fuursted K Schøler L Hansen F Dam K Bojer MS Hammerum AM Dagnæs-Hansen F Olsen A Jasemian Y Struve C 《Microbes and infection / Institut Pasteur》2012,14(2):155-158
The aim of the study was to compare and evaluate virulence in five strains of Klebsiella pneumoniae, including an isolate carrying New Delhi metallo-beta-lactamase-1 (NDM-1). In vivo virulence was assessed using a murine sepsis model and using the nematode Caenorhabditis elegans killing model, and in vitro virulence by assessing various virulence factors. The NDM-1 carrying K. pneumoniae isolate was the most virulent in the murine sepsis model but there was no clear cut correlation to in vitro virulence factors or killing in C. elegans. It is concluded that K. pneumoniae carrying NDM-1 have an intrinsic virulence potential, which in coexistence with its multiresistance could promote and partly explain its epidemiological success. 相似文献
65.
Background
Factors determining the onset and severity of chronic obstructive pulmonary disease remain poorly understood. Previous studies demonstrated that airway surface dehydration in βENaC-overexpressing (βENaC-Tg) mice on a mixed genetic background caused either neonatal mortality or chronic obstructive lung disease suggesting that the onset of lung disease was modulated by the genetic background.Methods
To test this hypothesis, we backcrossed βENaC-Tg mice onto two inbred strains (C57BL/6 and BALB/c) and studied effects of the genetic background on neonatal mortality, airway ion transport and airway morphology. Further, we crossed βENaC-Tg mice with CFTR-deficient mice to validate the role of CFTR in early lung disease.Results
We demonstrate that the C57BL/6 background conferred increased CFTR-mediated Cl− secretion, which was associated with decreased mucus plugging and mortality in neonatal βENaC-Tg C57BL/6 compared to βENaC-Tg BALB/c mice. Conversely, genetic deletion of CFTR increased early mucus obstruction and mortality in βENaC-Tg mice.Conclusions
We conclude that a decrease or absence of CFTR function in airway epithelia aggravates the severity of early airway mucus obstruction and related mortality in βENaC-Tg mice. These results suggest that genetic or environmental factors that reduce CFTR activity may contribute to the onset and severity of chronic obstructive pulmonary disease and that CFTR may serve as a novel therapeutic target. 相似文献66.
Neff Helmut Oliveira Leiva Casemiro Rodrigures Eloise Passos Thirstrup Carsten Lima Antonio Marcus Nogueira 《Plasmonics (Norwell, Mass.)》2018,13(6):2021-2027
Plasmonics - Massively enhanced directed radiation emission from periodically corrugated thin gold and silver films at the surface plasmon resonance is reported. The optical setup comprises... 相似文献
67.
We created a pair of vectors allowing simple and efficient molecular cloning of any gene of interest with minimal consumption of time, labor and material. This system is applicable for standard molecular cloning, high-throughput cloning and generation of fusion protein libraries as well as for more complex gene assembly purposes. Also, this zero-background procedure allows going from cDNA to gene expression analysis in a defined vector in <2 days. 相似文献
68.
Anke Kuppardt Sabine Kleinsteuber Carsten Vogt Tillmann Lüders Hauke Harms Antonis Chatzinotas 《Microbial ecology》2014,68(2):222-234
Three toluene-degrading microbial consortia were enriched under sulphate-reducing conditions from different zones of a benzene, toluene, ethylbenzene and xylenes (BTEX) plume of two connected contaminated aquifers. Two cultures were obtained from a weakly contaminated zone of the lower aquifer, while one culture originated from the highly contaminated upper aquifer. We hypothesised that the different habitat characteristics are reflected by distinct degrader populations. Degradation of toluene with concomitant production of sulphide was demonstrated in laboratory microcosms and the enrichment cultures were phylogenetically characterised. The benzylsuccinate synthase alpha-subunit (bssA) marker gene, encoding the enzyme initiating anaerobic toluene degradation, was targeted to characterise the catabolic diversity within the enrichment cultures. It was shown that the hydrogeochemical parameters in the different zones of the plume determined the microbial composition of the enrichment cultures. Both enrichment cultures from the weakly contaminated zone were of a very similar composition, dominated by Deltaproteobacteria with the Desulfobulbaceae (a Desulfopila-related phylotype) as key players. Two different bssA sequence types were found, which were both affiliated to genes from sulphate-reducing Deltaproteobacteria. In contrast, the enrichment culture from the highly contaminated zone was dominated by Clostridia with a Desulfosporosinus-related phylotype as presumed key player. A distinct bssA sequence type with high similarity to other recently detected sequences from clostridial toluene degraders was dominant in this culture. This work contributes to our understanding of the niche partitioning between degrader populations in distinct compartments of BTEX-contaminated aquifers. 相似文献
69.
Antiviral and regulatory T cell immunity in a patient with stromal interaction molecule 1 deficiency
Fuchs S Rensing-Ehl A Speckmann C Bengsch B Schmitt-Graeff A Bondzio I Maul-Pavicic A Bass T Vraetz T Strahm B Ankermann T Benson M Caliebe A Fölster-Holst R Kaiser P Thimme R Schamel WW Schwarz K Feske S Ehl S 《Journal of immunology (Baltimore, Md. : 1950)》2012,188(3):1523-1533
Stromal interaction molecule 1 (STIM1) deficiency is a rare genetic disorder of store-operated calcium entry, associated with a complex syndrome including immunodeficiency and immune dysregulation. The link from the molecular defect to these clinical manifestations is incompletely understood. We report two patients with a homozygous R429C point mutation in STIM1 completely abolishing store-operated calcium entry in T cells. Immunological analysis of one patient revealed that despite the expected defect of T cell proliferation and cytokine production in vitro, significant antiviral T cell populations were generated in vivo. These T cells proliferated in response to viral Ags and showed normal antiviral cytotoxicity. However, antiviral immunity was insufficient to prevent chronic CMV and EBV infections with a possible contribution of impaired NK cell function and a lack of NKT cells. Furthermore, autoimmune cytopenia, eczema, and intermittent diarrhea suggested impaired immune regulation. FOXP3-positive regulatory T (Treg) cells were present but showed an abnormal phenotype. The suppressive function of STIM1-deficient Treg cells in vitro, however, was normal. Given these partial defects in cytotoxic and Treg cell function, impairment of other immune cell populations probably contributes more to the pathogenesis of immunodeficiency and autoimmunity in STIM1 deficiency than previously appreciated. 相似文献
70.
The two lemon-shaped compound eyes of the moth Cameraria ohridella measure in dorsal–ventral direction 263.0 μm in male and 238.9 μm in female individuals. In anterior–posterior direction
no significant differences were found between the sexes, eye length being about 194.6 μm. The eyes of males consist of ca.
417 hexagonal facets, while those of females contain 367. In both sexes facet diameters are approximately 11.5 μm. Despite
the size differences of the eyes in the two sexes, ultrastructurally they are identical and both possess ommatidia of 80 μm
mean length. The ultrastructure of the eye is described and compared with that of other compound eyes of Lepidoptera. Anatomically
the eyes represent a type intermediate between apposition and refractive superposition kind. A distal rhabdom is present in
the space that in the eyes of larger moths with superposition optics is occupied by the so-called clear zone. A tracheal tapetum
and longitudinal screening pigment migrations, typical of superposition but not apposition eyes are present despite the lack
of a clear zone. Thus, our results support an earlier calculated minimal theoretical limit for superposition eyes. 相似文献