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61.
Hamako Sasamoto Akira Kondo Yoshihisa Hosoi Hisae Maki Keiji Odani 《In vitro cellular & developmental biology. Plant》1992,28(3):132-136
Summary Protoplasts were isolated from cotyledons of 1- to 1.5-mo.-old seedlings ofChamaecyparis obtusa using 1% driselase or 0.25% pectolyase Y-23 in combination with 1% cellulase RS in 0.6M mannitol solution. Cell division and colony formation were induced efficiently in liquid Murashige and Skoog’s (MS) medium
containing 0.6M mannitol and 10 to 30 μM 2,4-dichlorophenoxyacetic acid or 1 μM of naphthaleneacegic acid at the cell density of 1 to 2×103 ml. Continued callus proliferations was observed by transferring tissue to fresh medium of the same composition as the induction
medium without mannitol. Campbell and Durzan’s medium and ammonium nitrate-free MS medium were less effective than MS medium.
High concentration of benzyladenine (1 or 10 μM) was inhibitory to cell division. 相似文献
62.
F. Macrì E. Braidot E. Petrussa M. Zancani A. Vianello 《Plant biology (Stuttgart, Germany)》1992,105(2):97-103
This work was undertaken to verify whether surface NADH oxidases or peroxidases are involved in the apoplastic reduction of Fe(III). The reduction of Fe(III)-ADP, linked to NADH-dependent activity of horseradish peroxidase (HRP), protoplasts and cells of Acer pseudoplatanus, was measured as Fe(II)-bathophenanthrolinedisulfonate (BPDS) chelate formation. In the presence of BPDS in the incubation medium (method 1), NADH-dependent HRP activity was associated with a rapid Fe(III)-ADP reduction that was almost completely inhibited by superoxide dismutase (SOD), while catalase only slowed down the rate of reduction. A. pseudoplatanus protoplasts and cells reduced extracellular Fe(III)-ADP in the absence of exogenously supplied NADH. The addition of NADH stimulated the reduction. SOD and catalase only inhibited the NADH-dependent Fe(III)-ADP reduction. Mn(II), known for its ability to scavenge O?2, inhibited both the independent and NADH-dependent Fe(III)-ADP reduction. The reductase activity of protoplasts and cells was also monitored in the absence of BPDS (method 2). The latter was added only at the end of the reaction to evaluate Fe(II) formed. Also, in this case, both preparations reduced Fe(III)-ADP. However, the addition of NADH did not stimulate Fe(III)-ADP reduction but, instead, lowered it. This may be related to a re-oxidation of Fe(II) by H2O2 that could also be produced during NADH-dependent peroxidase activity. Catalase and SOD made the Fe(III)-ADP reduction more efficient because, by removing H2O2 (catalase) or preventing H2O2 formation (SOD), they hindered the re-oxidation of Fe(II) not chelated by BPDS. As with the result obtained by method 1, Mn(II) inhibited Fe(III)-ADP reduction carried out in the presence or absence of NADH. The different effects of SOD and Mn(II), both scavengers of O?2, may depend on the ability of Mn(II) to permeate the cells more easily than SOD. These results show that A. pseudoplatanus protoplasts and cells reduce extracellular Fe(III)-ADP. Exogenously supplied NADH induces an additional reduction of Fe(III) by the activity of NADH peroxidases of the plasmalemma or cell wall. However, the latter can also trigger the formation of H2O2 that, reacting with Fe(II) (not chelated by BPDS), generates hydroxyl radicals and converts Fe(II) to Fe(III) (Fenton's reaction). 相似文献
63.
64.
Cell wall-free protoplasts of P. cyclopium could regenerate a cell wall and form mycelia in liquid culture with high rates of viability. When calcium was added to the medium, protoplasts displayed biphasic accumulation with an immediate metabolism-independent adsorption phase, followed by slow metabolism-dependent uptake.Exposure of the protoplasts to Ca2+ for periods of 2 min, followed by incubation in calcium-free medium for 24 hours, was sufficient to induce conidiation with morphogenetic events parallel to those found in cultures containing calcium throughout the incubation period, and similar to those reported in cultures inoculated from conidia.The conidiation event caused by short exposure to calcium could be reversed, within 2 hours of Ca2+ addition, by a brief treatment with the specific calcium chelating agent BAPTA (100 M), which removed 65 to 75% of the total cell calcium.The results implicate the membrane-bound calcium fraction in the process of conidiation induction. 相似文献
65.
Levels of abscisis acid (ABA) were determined in isolated guard cell (GCP) and mesophyll cell (MCP) protoplasts of Vicia faba L. in relation to water stress. Incubation of GCP and MCP in 0.4 M or 0.8 M mannitol resulted in an average increase in the level of free abscisic acid (ABA) in the cells of 34% (GCP) and 38% (MCP) within 15–60 min. It is concluded that guard cell protoplasts form ABA in response to osmotic stress.Abbreviations ABA
abscisic acid
- BHT
butylated hydroxytoluene
- GCP
guard cell protoplasts
- MCP
mesophyll cell protoplasts
- MES
[2-(N-morpholino)-ethanesulfonic acid]
- TLC
thin layer chromatography
Part 20 in the series, Use of Immunoassay in Plant Science 相似文献
66.
R. Vunsh D. Aviv E. Galun 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1982,64(1):51-58
Summary Protoplasts were derived from haploid and diploid Nicotiana sylvestris and N. tabacum. Exposure of the protoplasts to mutagenic doses of ultraviolet (U.V.) radiation prior to two selection rounds in the presence of 4 mM (or 5 mM) and 8 mM of valine, respectively, was required to obtain cell lines with persistent valine resistance. Such lines were obtained from haploid and diploid N. sylvestris protoplasts as well as from haploid protoplasts of N. tabacum but not from (1.8 × 107) diploid N. tabacum protoplasts. The ratio between number of verified valine-resistant cell lines and the initial number of U.V. exposed protoplasts enabled the estimation of the following order of mutation frequency: haploid N. sylvestris > haploid N. tabacum > diploid N. sylvestris. Plants which retained the valine resistance and transmitted it to their sexual progeny were derived from the resistant cell lines. 相似文献
67.
The relationships between 49 naviculoid diatoms, currently arranged in 14 families and four orders were investigated using cladistic analysis in order to test the types of characters used in diatom systematics and to assess how well the current classification reflects possible phylogenetic relationships in this group. Some of the families and orders comprise taxa with different protoplast characters, or taxa with similar protoplast arrangements are placed in separate families or orders. Therefore as both cell wall and protoplast characters were used, three analyses were undertaken; total data, protoplast data and frustule data. The analyses support the recognition of the Mastogloiales (unequivocally) and the Cymbellales (largely) but indicate that some of the familial groupings are more ambiguous. The members of the Berkeleyaceae, Berkeleya, Parlibellus and Climaconeis, were never grouped together and Achnanthes brevipes never grouped with the other monoraphid diatoms, but usually with members of the Mastogloiales (total and protoplast data). Similarly, Round et al.’s familial groupings within the Cymbellales do not emerge from our analyses. Our results support the hypothesis that monoraphid genera have arisen independently from different naviculoid diatoms, and that Achnanthes sensu stricto should be transferred to the Mastogloiales. Some of the problems associated with incomplete information and inaccurate terminology are discussed briefly. 相似文献
68.
A barrier to cost-efficient biomanufacturing is the instability of engineered genetic elements, such as plasmids. Instability can also manifest at the whole-genome level, when fungal dikaryons revert to parental species due to nuclear segregation during cell division. Here, we show that by encapsulating Saccharomyces cerevisiae-Pichia stipitis dikaryons in an alginate matrix, we can limit cell division and preserve their expanded metabolic capabilities. As a proxy to cellulosic ethanol production, we tested the capacity of such cells to carry out ethanologenic fermentation of glucose and xylose, examining substrate use, ploidy, and cell viability in relation to planktonic fusants, as well as in relation to planktonic and encapsulated cell cultures consisting of mixtures of these species. Glucose and xylose consumption and ethanol production by encapsulated dikaryons were greater than planktonic controls. Simultaneous co-fermentation did not occur; rather the order and kinetics of glucose and xylose catabolism by encapsulated dikaryons were similar to cultures where the two species were encapsulated together. Over repeated cycles of fed-batch culture, encapsulated S. cerevisiae-P. stipitis fusants exhibited a dramatic increase in genomic stability, relative to planktonic fusants. Encapsulation also increased the stability of antibiotic-resistance plasmids used to mark each species and preserved a fixed ratio of S. cerevisiae to P. stipitis cells in mixed cultures. Our data demonstrate how encapsulating cells in an extracellular matrix restricts cell division and, thereby, preserves the stability and biological activity of entities ranging from genomes to plasmids to mixed populations, each of which can be essential to cost-efficient biomanufacturing. 相似文献
69.
《Bioscience, biotechnology, and biochemistry》2013,77(5):1126-1128
To develop a gene transformation method for Flammulina velutipes, we constructed a vector with hph gene under control of the trp1 gene promoter. The vector was integrated into protoplast derived from mycelia by the calcium-polyethylene glycol method, as it has not been reported for F. velutipes. Transformation efficiency was much improved when transformation was performed by the restriction enzyme mediated integration method. 相似文献
70.
《Bioscience, biotechnology, and biochemistry》2013,77(2):590-593
We established a new plant defense response assay using a transient expression system in rice protoplasts. The assay system sensitively detected defense induction by flagellin, which had previously been assigned to a specific elicitor. Our assay system provides a rapid and efficient way to dissect rice defense mechanisms. 相似文献