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991.
Azadeh Shojaei Farkhondeh Behjati Pupak Derakhshandeh-Peykar Maryam Razzaghy-Azar Hasan Otukesh Roxana Kariminejad Mohammad-Ali Dowlati Ali Rashidi-Nezhad Javad Tavakkoly-Bazzaz 《Gene》2013
Terminal 7q duplication and terminal 13q deletion are two conditions with variable phenotypes including microcephaly, thumb a-/hypoplasia, cortical dysplasia, microphtalmia, intellectual disability and dysmorphic features. We describe a boy born to a mother with a reciprocal t (7;13) who combines both a terminal 7q33-qter duplication and terminal 13q33-qter deletion through the inheritance of a derivative chromosome 13 (der (13)). The patient presented with developmental delay, facial and non-facial dysmorphic features, hypertonia, genital abnormality and skeletal malformation but no thumb a-/hypoplasia or microphtalmia. Knowing the exact breakpoints of his chromosomal aberrations using high resolution array CGH (aCGH) and comparison of his phenotypes with those of 24 and 59 previously published cases of 7q duplication and 13q deletion, respectively, allow us to further narrow the size of the proposed critical regions for microcephaly, thumb a-/hypoplasia and hypo/hypertonia on chromosome 13. 相似文献
992.
Strategic genome-scale prioritization of unique drug targets: A case study of Streptococcus gordonii
Sandeep Telkar Hulikal shivashankara Santosh Kumar Nagaraja Deeplanaik Riaz Mahmood 《Bioinformation》2013,9(19):983-987
The current reach of genomics extends facilitated identification of microbial virulence factors, a primary objective for antimicrobial
drug and vaccine design. Many putative proteins are yet to be identified which can act as potent drug targets. There is lack and
limitation of methods which appropriately combine several omics ways for putative and new drug target identification. The study
emphasizes a combined bioinformatic and theoretical method of screening unique and putative drug targets, lacking similarity
with experimentally reported essential genes and drug targets. Synteny based comparison was carried out with 11 streptococci
considering S. gordonii as reference genome. It revealed 534 non-homologous genes of which 334 were putative. Similarity search
against host proteome, metabolic pathway annotation and subcellular localization predication identified 16 potent drug targets.
This is a first attempt of several combinational approaches of similarity search with target protein structural features for screening
drug targets, yielding a pipeline which can be substantiated to other human pathogens. 相似文献
993.
Computational simulation of internal bone remodelling around dental implants: a sensitivity analysis
Istabrak Hasan Alireza Rahimi Ludger Keilig Kai-Thomas Brinkmann 《Computer methods in biomechanics and biomedical engineering》2013,16(8):807-814
This study aimed to predict the distribution of bone trabeculae, as a density change per unit time, around a dental implant based on applying a selected mathematical remodelling model. The apparent bone density change as a function of the mechanical stimulus was the base of the applied remodelling model that describes disuse and overload bone resorption. The simulation was tested in a finite element model of a screw-shaped dental implant in an idealised bone segment. The sensitivity of the simulation to different mechanical parameters was investigated; these included element edge length, boundary conditions, as well as direction and magnitude of the implant loads. The alteration in the mechanical parameters had a significant influence on density distribution and model stability, in particular at the cortical bone region. The remodelling model could succeed to achieve trabeculae-like structure around osseointegrated dental implants. The validation of this model to a real clinical case is required. 相似文献
994.
Mustafeez Mujtaba Babar Muhammad Suleman Riaz Najam-us-Sahar Sadaf Zaidi Farhan Afzal Muhammad Sabir Farooq 《Journal of industrial microbiology & biotechnology》2013,40(6):625-632
The global availability of a therapeutically effective influenza virus vaccine during a pandemic remains a major challenge for the biopharmaceutical industry. Long production time, coupled with decreased supply of embryonated chicken eggs (ECE), significantly affects the conventional vaccine production. Transformed cell lines have attained regulatory approvals for vaccine production. Based on the fact that the avian influenza virus would infect the cells derived from its natural host, the viral growth characteristics were studied on chicken embryo-derived primary cell cultures. The viral propagation was determined on avian origin primary cell cultures, transformed mammalian cell lines, and in ECE. A comparison was made between these systems by utilizing various cell culture-based assays. In-vitro substrate susceptibility and viral infection characteristics were evaluated by performing hemagglutination assay (HA), 50 % tissue culture infectious dose (TCID50) and monitoring of cytopathic effects (CPE) caused by the virus. The primary cell culture developed from chicken embryos showed stable growth characteristics with no contamination. HA, TCID50, and CPE exhibited that these cell systems were permissive to viral infection, yielding 2–10 times higher viral titer as compared to mammalian cell lines. Though the viral output from the ECE was equivalent to the chicken cell culture, the time period for achieving it was decreased to half. Some of the prerequisites of inactivated influenza virus vaccine production include generation of higher vial titer, independence from exogenous sources, and decrease in the production time lines. Based on the tests, it can be concluded that chicken embryo primary cell culture addresses these issues and can serve as a potential alternative for influenza virus vaccine production. 相似文献
995.
Lead impacts neuromuscular junction and might induce skeletal muscle weakness. Antioxidants may prevent toxic actions of lead on muscle. In this study, resting membrane potentials, endplate potentials, miniature endplate potentials (MEPPs) and isometric twitch tensions were recorded to investigate effects of α-tocopherol (Vitamin E) on lead induced changes at murine dorsiflexor muscle. Moreover, levels of endplate nicotinic receptors were measured by receptor autoradiography. Forty rats were divided into four groups (lead alone, α-tocopherol, lead plus α-tocopherol and saline). Lead (1?mg/kg, i.p.), was administered daily for 2 weeks and α-tocopherol (100?mg/kg, i.p.) was given daily for 3 weeks. Lead treatment significantly reduced twitch tension (from 4.4±0.4 to 2.2±0.3?g) and delayed half time of decay. MEPP frequencies and quantal content were also significantly reduced after lead treatment. Pretreatment with α-tocopherol reversed twitch tension reduction (4.1±0.3?g) and modified lead induced delay in half time of decay. Similarly, α-tocopherol modified the negative actions of lead exposure on MEPP frequencies and quantal content. Receptor autoradiographic studies revealed significant increase of nicotinic receptor levels at the endplate region of flexor muscle in lead treated mice. However, animals treated with lead plus α-tocopherol showed significantly decreased levels of nicotinic receptors. α-Tocopherol appears to protect against lead induced neuromuscular dysfunction. These effects of α-tocopherol are possibly mediated via a free radical mechanism or modification of calcium homeostasis. 相似文献
996.
The grape antioxidant resveratrol for skin disorders: promise, prospects, and challenges 总被引:1,自引:0,他引:1
Resveratrol, a phytoalexin antioxidant found in red grapes, has been shown to have both chemopreventive and therapeutic effects against many diseases and disorders, including those of the skin. Studies have shown protective effects of resveratrol against ultraviolet radiation-mediated oxidative stress and cutaneous damages including skin cancer. Because many of the skin conditions stem from ultraviolet radiation and oxidative stress, this antioxidant appears to have promise and prospects against a wide range of cutaneous disorders including skin aging and skin cancers. However, there are a few roadblocks in the way of this promising agent regarding its translation from the bench to the bedside. This review discusses the promise and prospects of resveratrol in the management of skin disorders and the associated challenges. 相似文献
997.
998.
Genome sequences of the biotechnologically important Bacillus megaterium strains QM B1551 and DSM319 总被引:1,自引:0,他引:1
Eppinger M Bunk B Johns MA Edirisinghe JN Kutumbaka KK Koenig SS Creasy HH Rosovitz MJ Riley DR Daugherty S Martin M Elbourne LD Paulsen I Biedendieck R Braun C Grayburn S Dhingra S Lukyanchuk V Ball B Ul-Qamar R Seibel J Bremer E Jahn D Ravel J Vary PS 《Journal of bacteriology》2011,193(16):4199-4213
Bacillus megaterium is deep-rooted in the Bacillus phylogeny, making it an evolutionarily key species and of particular importance in understanding genome evolution, dynamics, and plasticity in the bacilli. B. megaterium is a commercially available, nonpathogenic host for the biotechnological production of several substances, including vitamin B(12), penicillin acylase, and amylases. Here, we report the analysis of the first complete genome sequences of two important B. megaterium strains, the plasmidless strain DSM319 and QM B1551, which harbors seven indigenous plasmids. The 5.1-Mbp chromosome carries approximately 5,300 genes, while QM B1551 plasmids represent a combined 417 kb and 523 genes, one of the largest plasmid arrays sequenced in a single bacterial strain. We have documented extensive gene transfer between the plasmids and the chromosome. Each strain carries roughly 300 strain-specific chromosomal genes that account for differences in their experimentally confirmed phenotypes. B. megaterium is able to synthesize vitamin B(12) through an oxygen-independent adenosylcobalamin pathway, which together with other key energetic and metabolic pathways has now been fully reconstructed. Other novel genes include a second ftsZ gene, which may be responsible for the large cell size of members of this species, as well as genes for gas vesicles, a second β-galactosidase gene, and most but not all of the genes needed for genetic competence. Comprehensive analyses of the global Bacillus gene pool showed that only an asymmetric region around the origin of replication was syntenic across the genus. This appears to be a characteristic feature of the Bacillus spp. genome architecture and may be key to their sporulating lifestyle. 相似文献
999.
A quantitative approach to characterize lignin–carbohydrate complex (LCC) linkages using a combination of quantitative 13C NMR and HSQC 2D NMR techniques has been developed. Crude milled wood lignin (MWLc), LCC extracted from MWLc with acetic
acid (LCC-AcOH) and cellulolytic enzyme lignin (CEL) preparations were isolated from loblolly pine (Pinus taeda) and white birch (Betula pendula) woods and characterized using this methodology on a routine 300 MHz NMR spectrometer and on a 950 MHz spectrometer equipped
with a cryogenic probe. Structural variations in the pine and birch LCC preparations of different types (MWL, CEL and LCC-AcOH)
were elucidated. The use of the high field NMR spectrometer equipped with the cryogenic probe resulted in a remarkable improvement
in the resolution of the LCC signals and, therefore, is of primary importance for an accurate quantification of LCC linkages.
The preparations investigated showed the presence of different amounts of benzyl ether, γ-ester and phenyl glycoside LCC bonds.
Benzyl ester moieties were not detected. Pine LCC-AcOH and birch MWLc preparations were preferable for the analysis of phenyl
glycoside and ester LCC linkages in pine and birch, correspondingly, whereas CEL preparations were the best to study benzyl
ether LCC structures. The data obtained indicate that pinewood contains higher amounts of benzyl ether LCC linkages, but lower
amounts of phenyl glycoside and γ-ester LCC moieties as compared to birch wood. 相似文献
1000.
Riaz S Tenscher AC Ramming DW Walker MA 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2011,122(6):1059-1073
A limited genetic mapping strategy based on simple sequence repeat (SSR) marker data was used with five grape populations
segregating for powdery mildew (Erysiphe necator) resistance in an effort to develop genetic markers from multiple sources and enable the pyramiding of resistance loci. Three
populations derived their resistance from Muscadinia rotundifolia ‘Magnolia’. The first population (06708) had 97 progeny and was screened with 137 SSR markers from seven chromosomes (4,
7, 9, 12, 13, 15, and 18) that have been reported to be associated with powdery or downy mildew resistance. A genetic map
was constructed using the pseudo-testcross strategy and QTL analysis was carried out. Only markers from chromosome 13 and
18 were mapped in the second (04327) and third (06712) populations, which had 47 and 80 progeny, respectively. Significant
QTLs for powdery mildew resistance with overlapping genomic regions were identified for different tissue types (leaf, stem,
rachis, and berry) on chromosome 18, which distinguishes the resistance in ‘Magnolia’ from that present in other accessions
of M. rotundifolia and controlled by the Run1 gene on chromosome 12. The ‘Magnolia’ resistance locus was termed as Run2.1. Powdery mildew resistance was also mapped in a fourth population (08391), which had 255 progeny and resistance from M. rotundifolia ‘Trayshed’. A locus accounting for 50% of the phenotypic variation mapped to chromosome 18 and was named Run2.2. This locus overlapped the region found in the ‘Magnolia’-based populations, but the allele sizes of the flanking markers
were different. ‘Trayshed’ and ‘Magnolia’ shared at least one allele for 68% of the tested markers, but alleles of the other
32% of the markers were not shared indicating that the two M. rotundifolia selections were very different. The last population, 08306 with 42 progeny, derived its resistance from a selection Vitis romanetii C166-043. Genetic mapping discovered a major powdery mildew resistance locus termed Ren4 on chromosome 18, which explained 70% of the phenotypic variation in the same region of chromosome 18 found in the two M. rotundifolia resistant accessions. The mapping results indicate that powdery mildew resistance genes from different backgrounds reside
on chromosome 18, and that genetic markers can be used as a powerful tool to pyramid these loci and other powdery mildew resistance
loci into a single line. 相似文献