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1.
A Taddeo A Renieri A Fioravanti G Morozzi E Parrini M S D'Amato M G Ricci 《Bollettino della Società italiana di biologia sperimentale》1984,60(9):1709-1714
Modifications on the binding of uric acid to human plasma proteins have been studied in regularly menstruating females aged 25-30 years with a normal cycle, in comparison with a group of healthy age-matched males and with a group of post-menopausal females. The binding of uric acid to plasma proteins was estimated using micropartition system Amicon. The results obtained demonstrate a significant increase of uric acid binding during ovulatory and mid-luteal phase of menstrual cycle. No modifications are shown in post-menopausal females and in healthy males. No modifications have been shown with the same experiments performed in vitro. 相似文献
2.
F Petraglia F Facchinetti D Parrini A R Genazzani 《Bollettino della Società italiana di biologia sperimentale》1981,57(18):1862-1868
To evaluate the rabbit availability in beta-Lipotrophin studies we have investigated their brain, pituitary and plasmatic concentrations in basal conditions and after cold-stress. Previous silicic Acid extract and Sephadex G-75 column chromatography, the two peptides were measured through two specific and sensitive RIAs. The results reveal the presence of beta LPH and beta EP and their increase after cold-stress in hypothalamus, pituitary and peripheral plasma concentrations while not in midbrain. 相似文献
3.
4.
Background
Expression systems based on self-cleavable intein domains allow the generation of recombinant proteins with a C-terminal thioester. This uniquely reactive C-terminus can be used in native chemical ligation reactions to introduce synthetic groups or to immobilize proteins on surfaces and nanoparticles. Unfortunately, common refolding procedures for recombinant proteins that contain disulfide bonds do not preserve the thioester functionality and therefore novel refolding procedures need to be developed. 相似文献5.
An efficient and rapid procedure for plantlet regeneration from chicory mesophyll protoplasts 总被引:2,自引:0,他引:2
An efficient procedure for plantlet regeneration from chicory mesophyll protoplasts has been developed in order to perform
protoplast fusion experiments. Protoplasts were isolated from a genotype of Italian red chicory (CH 363) and purified by centrifugation
in a solution containing 13% (w/v) sucrose to collect uniform protoplasts in size. After 2 days culture at a density of 2×104 protoplasts ml−1 of liquid medium, protoplasts were cultured following three different procedures: in liquid medium, stratified in semi-solid
medium, and embedded in Ca-alginate droplets. Four different media were used and culture procedures were evaluated recording
the protoplast viability, protoplast division frequency and plating efficiency for each experiment. The embedding of protoplasts
in Ca-alginate droplets enhanced both division frequency and plating efficiency for chicory mesophyll cells. Furthermore,
this procedure shortened the cycle of plant regeneration from protoplasts, which could be completed in eight weeks.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
6.
Patrick LJM Zeeuwen Jos Boekhorst Ellen H van den Bogaard Heleen D de Koning Peter MC van de Kerkhof Delphine M Saulnier Iris I van Swam Sacha AFT van Hijum Michiel Kleerebezem Joost Schalkwijk Harro M Timmerman 《Genome biology》2012,13(11):R101
Background
Recent advances in sequencing technologies have enabled metagenomic analyses of many human body sites. Several studies have catalogued the composition of bacterial communities of the surface of human skin, mostly under static conditions in healthy volunteers. Skin injury will disturb the cutaneous homeostasis of the host tissue and its commensal microbiota, but the dynamics of this process have not been studied before. Here we analyzed the microbiota of the surface layer and the deeper layers of the stratum corneum of normal skin, and we investigated the dynamics of recolonization of skin microbiota following skin barrier disruption by tape stripping as a model of superficial injury.Results
We observed gender differences in microbiota composition and showed that bacteria are not uniformly distributed in the stratum corneum. Phylogenetic distance analysis was employed to follow microbiota development during recolonization of injured skin. Surprisingly, the developing neo-microbiome at day 14 was more similar to that of the deeper stratum corneum layers than to the initial surface microbiome. In addition, we also observed variation in the host response towards superficial injury as assessed by the induction of antimicrobial protein expression in epidermal keratinocytes.Conclusions
We suggest that the microbiome of the deeper layers, rather than that of the superficial skin layer, may be regarded as the host indigenous microbiome. Characterization of the skin microbiome under dynamic conditions, and the ensuing response of the microbial community and host tissue, will shed further light on the complex interaction between resident bacteria and epidermis. 相似文献7.
Andréia S Lessa Bruno D Paredes Juliana V Dias Adriana B Carvalho Luiz Fernando Quintanilha Christina M Takiya Bernardo R Tura Guilherme FM Rezende Antonio C Campos de Carvalho Célia MC Resende Regina CS Goldenberg 《BMC veterinary research》2010,6(1):1-10
Background
Atypical scrapie was first identified in Norwegian sheep in 1998 and has subsequently been identified in many countries. Retrospective studies have identified cases predating the initial identification of this form of scrapie, and epidemiological studies have indicated that it does not conform to the behaviour of an infectious disease, giving rise to the hypothesis that it represents spontaneous disease. However, atypical scrapie isolates have been shown to be infectious experimentally, through intracerebral inoculation in transgenic mice and sheep. The first successful challenge of a sheep with 'field' atypical scrapie from an homologous donor sheep was reported in 2007.Results
This study demonstrates that atypical scrapie has distinct clinical, pathological and biochemical characteristics which are maintained on transmission and sub-passage, and which are distinct from other strains of transmissible spongiform encephalopathies in the same host genotype.Conclusions
Atypical scrapie is consistently transmissible within AHQ homozygous sheep, and the disease phenotype is preserved on sub-passage. 相似文献8.
Immature embryos culture in Italian red chicory 总被引:3,自引:0,他引:3
Varotto Serena Lucchin Margherita Parrini Paolo 《Plant Cell, Tissue and Organ Culture》2000,62(1):75-77
Chicory (Cichorium intybus L.) embryo maturation in vitro was achieved in B5 medium without growth regulators. Immature embryos were collected at different developmental stages 4–168
h after pollination. Only a few plantlets were obtained from ovules collected shortly after pollination since the embryos
at these early stages developed abnormal leaves and roots which regenerated shoots ‘via’ organogenesis. Zygotic embryos collected
24–72 h after pollination needed one month of culture in vitro before acclimation. Embryos collected at the heart or early torpedo stage of development (three days after pollination) produced
green plantlets after two weeks of in vitro culture and thus they could be transferred to the greenhouse for acclimation. Culture of zygotic embryos in vitro has shown to be a suitable technique to accelerate the breeding process in biennial cultivated Italian red chicory. In fact
it is possible to obtain plantlets ready for performing the selection for the desired agronomic traits one month after pollination.
Since flowering occurs after vernalization, the selection can be performed in the correct season before flowering.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
9.
Claudia T Guimaraes Christiano C Simoes Maria Marta Pastina Lyza G Maron Jurandir V Magalhaes Renato CC Vasconcellos Lauro JM Guimaraes Ubiraci GP Lana Carlos FS Tinoco Roberto W Noda Silvia N Jardim-Belicuas Leon V Kochian Vera MC Alves Sidney N Parentoni 《BMC genomics》2014,15(1)
Background
Aluminum (Al) toxicity is an important limitation to food security in tropical and subtropical regions. High Al saturation on acid soils limits root development, reducing water and nutrient uptake. In addition to naturally occurring acid soils, agricultural practices may decrease soil pH, leading to yield losses due to Al toxicity. Elucidating the genetic and molecular mechanisms underlying maize Al tolerance is expected to accelerate the development of Al-tolerant cultivars.Results
Five genomic regions were significantly associated with Al tolerance, using 54,455 SNP markers in a recombinant inbred line population derived from Cateto Al237. Candidate genes co-localized with Al tolerance QTLs were further investigated. Near-isogenic lines (NILs) developed for ZmMATE2 were as Al-sensitive as the recurrent line, indicating that this candidate gene was not responsible for the Al tolerance QTL on chromosome 5, qALT5. However, ZmNrat1, a maize homolog to OsNrat1, which encodes an Al3+ specific transporter previously implicated in rice Al tolerance, was mapped at ~40 Mbp from qALT5. We demonstrate for the first time that ZmNrat1 is preferentially expressed in maize root tips and is up-regulated by Al, similarly to OsNrat1 in rice, suggesting a role of this gene in maize Al tolerance. The strongest-effect QTL was mapped on chromosome 6 (qALT6), within a 0.5 Mbp region where three copies of the Al tolerance gene, ZmMATE1, were found in tandem configuration. qALT6 was shown to increase Al tolerance in maize; the qALT6-NILs carrying three copies of ZmMATE1 exhibited a two-fold increase in Al tolerance, and higher expression of ZmMATE1 compared to the Al sensitive recurrent parent. Interestingly, a new source of Al tolerance via ZmMATE1 was identified in a Brazilian elite line that showed high expression of ZmMATE1 but carries a single copy of ZmMATE1.Conclusions
High ZmMATE1 expression, controlled either by three copies of the target gene or by an unknown molecular mechanism, is responsible for Al tolerance mediated by qALT6. As Al tolerant alleles at qALT6 are rare in maize, marker-assisted introgression of this QTL is an important strategy to improve maize adaptation to acid soils worldwide.Electronic supplementary material
The online version of this article (doi:10.1186/1471-2164-15-153) contains supplementary material, which is available to authorized users. 相似文献10.