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81.
Detection and quantification of Entomophaga maimaiga resting spores in forest soil using real-time PCR 总被引:2,自引:0,他引:2
Louela A. Castrillo Lene Thomsen Punita Juneja Ann E. Hajek 《Mycological Research》2007,111(3):324-331
Environmental sampling to monitor entomopathogen titre in forest soil, a known reservoir of insect pathogens such as fungi and viruses, is important in the evaluation of conditions that could trigger epizootics and in the development of strategies for insect pest management. Molecular or PCR-based analysis of environmental samples provides a sensitive method for strain- or species-based detection, and real-time PCR, in particular, allows quantification of the organism of interest. In this study we developed a DNA extraction method and a real-time PCR assay for detection and quantification of Entomophaga maimaiga (Zygomycetes: Entomophthorales), a fungal pathogen of the gypsy moth, in the organic layer of forest soil. DNA from fungal resting spores (azygospores) in soil was extracted using a detergent and bead mill homogenization treatment followed by purification of the crude DNA extract using Sephadex–polyvinylpolypyrrolidone microcolumns. The purification step eliminated most of the environmental contaminants commonly co-extracted with genomic DNA from soil samples but detection assays still required the addition of bovine serum albumin to relieve PCR inhibition. The real-time PCR assay used primers and probe based on sequence analysis of the nuclear ribosomal ITS region of several E. maimaiga and two E. aulicae strains. Comparison of threshold cycle values from different soil samples spiked with E. maimaiga DNA showed that soil background DNA and remaining co-extracted contaminants are critical factors determining detection sensitivity. Based on our results from comparisons of resting spore titres among different forest soils, estimates were best for organic soils with comparatively high densities of resting spores. 相似文献
82.
Gorodkin J Cirera S Hedegaard J Gilchrist MJ Panitz F Jørgensen C Scheibye-Knudsen K Arvin T Lumholdt S Sawera M Green T Nielsen BJ Havgaard JH Rosenkilde C Wang J Li H Li R Liu B Hu S Dong W Li W Yu J Wang J Staefeldt HH Wernersson R Madsen LB Thomsen B Hornshøj H Bujie Z Wang X Wang X Bolund L Brunak S Yang H Bendixen C Fredholm M 《Genome biology》2007,8(4):R45-16
83.
Background
There are no published studies on stem cells from equine cord blood although commercial storage of equine cord blood for future autologous stem cell transplantations is available. Mesenchymal stem cells (MSC) have been isolated from fresh umbilical cord blood of humans collected non-invasively at the time of birth and from sheep cord blood collected invasively by a surgical intrauterine approach. Mesenchymal stem cells isolation percentage from frozen-thawed human cord blood is low and the future isolation percentage of MSCs from cryopreserved equine cord blood is therefore expectedly low. The hypothesis of this study was that equine MSCs could be isolated from fresh whole equine cord blood. 相似文献84.
Zhang Yang Catharina Steentoft Camilla Hauge Lars Hansen Allan Lind Thomsen Francesco Niola Malene B. Vester-Christensen Morten Fr?din Henrik Clausen Hans H. Wandall Eric P. Bennett 《Nucleic acids research》2015,43(9):e59
The nuclease-based gene editing tools are rapidly transforming capabilities for altering the genome of cells and organisms with great precision and in high throughput studies. A major limitation in application of precise gene editing lies in lack of sensitive and fast methods to detect and characterize the induced DNA changes. Precise gene editing induces double-stranded DNA breaks that are repaired by error-prone non-homologous end joining leading to introduction of insertions and deletions (indels) at the target site. These indels are often small and difficult and laborious to detect by traditional methods. Here we present a method for fast, sensitive and simple indel detection that accurately defines indel sizes down to ±1 bp. The method coined IDAA for Indel Detection by Amplicon Analysis is based on tri-primer amplicon labelling and DNA capillary electrophoresis detection, and IDAA is amenable for high throughput analysis. 相似文献
85.
86.
Thomsen PD Schauser K Bertelsen MF Vejlsted M Grøndahl C Christensen K 《Cytogenetic and genome research》2011,132(1-2):124-128
Mating of a babirusa (Babyrousa babyrussa) boar and a domestic sow (Sus scrofa) resulted in the birth of 5 live domestic pig-babirusa hybrid piglets. Chromosome analysis of one of the surviving males confirmed that they were domestic pig-babirusa hybrids by revealing the presence of a complete haploid set of 19 porcine chromosomes as well as a complete haploid set of 19 babirusa chromosomes in the karyotype. None of the surviving piglets, two males and one female, had shown signs of sexual maturity at age 27 months. Histological examination of gonadal biopsies from the 2 males revealed that both were azoospermatic. Immunostaining revealed SCP3-positive axial elements in the nuclei of primary spermatocytes, indicating that they were progressing through leptotene and zygotene of meiotic prophase. However, the presence of multiple short stretches of axial elements in pachytene nuclei indicated that this phase was blocked, probably due to aberrant chromosome pairing. Histological examination of the ovaries revealed follicular structures, but oocytes within them were generally degenerated. We conclude that both male and female pig-babirusa hybrids were infertile, most likely due to germ cell death resulting from abnormalities of chromosome pairing during meiotic prophase. 相似文献
87.
Thomsen MH 《Applied microbiology and biotechnology》2005,68(5):598-606
This mini-review describes the concept of the green biorefinery and lists a number of suitable agricultural by-products, which
can be used for production of bioenergy and/or biochemicals. A process, in which one possible agricultural by-product from
the green crop drying industry, brown juice, is converted to a basic, universal fermentation medium by lactic acid fermentation,
is outlined. The resulting all-round fermentation medium can be used for the production of many useful fermentation products
when added a carbohydrate source, which could possibly be another agricultural by-product. Two examples of such products—polylactic
acid and l-lysine—are given. A cost calculation shows that this fermentation medium can be produced at a very low cost ≈1.7 Euro cent/kg,
when taking into account that the green crop industry has expenses amounting to 270,000 Euro/year for disposal of the brown
juice. A newly built lysine factory in Esbjerg, Denmark, can benefit from this process by buying a low price medium for the
fermentation process instead of more expensive traditional fermentation liquids such as corn steep liquor. 相似文献
88.
Smith BM Smith JM Tsai JH Schultz JA Gilson CA Estrada SA Chen RR Park DM Prieto EB Gallardo CS Sengupta D Thomsen WJ Saldana HR Whelan KT Menzaghi F Webb RR Beeley NR 《Bioorganic & medicinal chemistry letters》2005,15(5):1467-1470
We report on the synthesis, biological evaluation and structure-activity relationships for a series of 3-benzazepine derivatives as 5-HT(2C) receptor agonists. The compounds were evaluated in functional assays measuring [3H] phosphoinositol turnover in HEK-293 cells transiently transfected with h5-HT(2C), h5-HT(2A) or h5-HT(2B) receptors. Several compounds are shown to be potent and selective 5-HT(2C) receptor agonists, which decrease food intake in a rat feeding model. 相似文献
89.
Culture-independent investigations of the bacterial diversity and activity in district heating systems with and without corrosion did not make it possible to relate one group of microorganisms with the observed corrosion. Fluorescence in situ hybridization by oligonucleotide probes revealed the dominance of beta-proteobacteria, sulphate reducing prokaryotes and alpha-proteobacteria. Analysis of a clone library from one Danish heating (DH) system showed that the most sequences formed two clusters within the alpha-proteobacteria affiliated to the families Rhizobiaceae and Acetobacteraceae and two clusters within the beta-proteobacteria belonging to the family Comamonadaceae. Functional groups were determined by microautoradiography showing aerobic and anaerobic bacteria (sulphate reducing and methanogenic bacteria). The corrosion study showed that pitting corrosion rates were five to ten times higher than the general corrosion rates, suggesting the presence of biocorrosion. The results indicate that several bacterial groups could be involved in corrosion of DH system piping including sulphate reducing prokaryotes, Acidovorax (within the beta-proteobacteria), methanogenic bacteria and others. 相似文献
90.
ARID domain proteins are members of a highly conserved family involved in chromatin remodeling and cell-fate determination. Dril1 is the founding member of the ARID family and is involved in developmental processes in both Drosophila and Caenorhabditis elegans. We describe the first embryological characterization of this gene in chordates. Dril1 mRNA expression is spatiotemporally regulated and is detected in the involuting mesoderm during gastrulation. Inhibition of dril1 by either a morpholino or an engrailed repressor-dril1 DNA binding domain fusion construct inhibits gastrulation and perturbs induction of the zygotic mesodermal marker Xbra and the organizer markers chordin, noggin, and Xlim1. Xenopus tropicalis dril1 morphants also exhibit impaired gastrulation and axial deficiencies, which can be rescued by coinjection of Xenopus laevis dril1 mRNA. Loss of dril1 inhibits the response of animal caps to activin and secondary axis induction by smad2. Dril1 depletion in animal caps prevents both the smad2-mediated induction of dorsal mesodermal and endodermal markers and the induction of ventral mesoderm by smad1. Mesoderm induction by eFGF is uninhibited in dril1 morphant caps, reflecting pathway specificity for dril1. These experiments identify dril1 as a novel regulator of TGF(beta) signaling and a vital component of mesodermal patterning and embryonic morphogenesis. 相似文献