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561.
Samuel J. Karunyal Andrews B. Jebashree H. Shyla 《World journal of microbiology & biotechnology》2000,16(7):617-620
The aqueous extract of Allium sativum bulbs showed an antifungal effect against the fungal skin pathogen, Trichophyton rubrum, isolated from infected patients. For a given concentration (200 mg of bulbs/1 ml), the volume of the aqueous garlic extract
loaded on to the discs, and the diameter of the inhibitory zone formed around the disc on the fungal lawn showed positive
correlation. Extract-included microbial assay confirmed the antifungal effect of Allium sativum. The extract was not heat stable, it lost its antifungal property above 60 °C.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
562.
Onion microsatellites for germplasm analysis and their use in assessing intra- and interspecific relatedness within the subgenus Rhizirideum 总被引:3,自引:0,他引:3
D. Fischer K. Bachmann 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2000,101(1-2):153-164
We have identified a set of informative STMS markers in onion (Allium cepa L.) and report on their application for genotyping and for determining genetic relationships. The markers have been developed
from a genomic library enriched for microsatellites. Integrity of the microsatellite polymorphism was confirmed by amplicon
sequencing. The microsatellite genotypes of 83 onion accessions and landraces from living onion collections were compared.
As few as four primer pairs were sufficient to assign unique microsatellite patterns to the 83 accessions. Some of the microsatellite
markers can be used for interspecific taxonomic analyses among close relatives of Allium cepa. Generally, our data support and extend results obtained from recently performed analyses using ITS, RAPD and morphology.
Received: 8 October 1999 / Accepted: 3 November 1999 相似文献
563.
564.
大蒜分生组织培养脱病毒和快速繁殖技术 总被引:10,自引:1,他引:9
采用茎尖分生组织培养技术,获得了大蒜(Allium sativum L.)的无病毒试管苗。通过基本培养基和激素配比试验,筛选出最佳的培养基组成,进行脱病毒苗的快速繁殖。结果表明:诱导愈伤组织的最适培养基为:MS+BA0.2mg/L+NAA0.5mg/L,月生长率达12.70倍;诱导丛生芽的最适培养基为:B5+BA0.5mg/L+IAA0.2mg/L,丛生芽繁殖系数高达25.5倍,技术上达到了快速繁 相似文献
565.
Using immunofluorescent localization techniques and TEM methods, the organization of microtubule arrays during the cell cycle of root tip cells of Allium fistulosum L. was studied. There are four basic types of microtubule organization, namely, interphase cortical microtubule, pre-prophase band microtubule, spindle microtubule and phragmoplast microtubule, which constitute the typical microtubule cycle in dividing cells of higher plants. The fluorescent figures of microtubules observed under fluorescent microscope were explained and analysed by the ultrastractural informations of microtubules obtained from TEM. 相似文献
566.
The present papar is a report on cytotaxonomical studies of Allium Sect. Caloscordum(Liliaceae)from China. Six populations of A. neriniflorum and A.tubiflorum
were introduced from Shaanxi,Hebei(Beijing),Liaoning and Heilongjiang.Based on the introduction and cultivated experiment, the authors made a karyotype analysis and a morphological comparison of the six populations. The results are as follows. Except the population 5 (Baihuashan,Beijing),which was found to be tetraploid 2n=4x=32,all the populations were dipliod 2n=2x=16. There were two types of satellites: terminal and intercalary. The basic number,the karyotypes as well as the types of satellites in Sect. Caloscordum were the same as those in the other sections of Allium.
In the populations 1, 2, 3 and 4(Daheshan,Jinxia County,Liaoning;Taikang County, Heilongjiang; Chengde to Huaqing, Hebei; Liulimao, Huairou,Beijing.), the sixth pair of chromosomes had a pair of intercalary satellites,the mean length of pedicels is about 7 cm and the plant had no two-growth cycle.In the populations 6 (Xianyunei, Huashan, Shaanxi): the eighth chromosome pair had a pair of terminal satellites, the pedicel was shorter,with the mean length 2.39 cm,and the plant had two-growth cycle.
In the tetraploid population 5; fourteenth and sixteenth chromosome pairs both had a pair of terminal satellites,the mean length of pedicel was 2.39 cm and the plant had the two-growth cycle.According to the results,the authors keep Sect. Caloscordum in the genus Allium and recognize two species in China in the section; the populations 1, 2, 3 and 4 belong to A.neriniflorum,and the populations 5 and 6 to A.tubiflorum.Our observation on dissecting ovary showed that there were 2~11 ovules per locule;the diploid populations mainly had 5 ~6 ovules per locule,while the tetraploid ones mainly had 4 ovules per locule.Therefore, the number of ovules per locule is not a reliable character for classifiction but it may be useful in distinguishing diploid from tetraploid.However,we consider that the satellite type,the pedicel length and whether the plant has two-growth cycle are the diagnostic features for the species of Sect.Caloscordum. 相似文献
567.
568.
Chromosomal ultrastructure and ribonucleoproteins (RNP) at mitotic metaphase in garlic (Allium sativum L. ) were studied. Areas of low electron in density were observed in the centre of some chromosomes with double staining with Ag staining technic. These areas of low electronic density were further observed as perferated holes. With Bernhard staining technique RNP could be detected in the holes but not evenly distributed. RNA identification was further ascertained by NaOH-treatment. The amount of RNP visualized in Bernhard staining technique gradually faded as the duration of EDTA treatment was in creased. 相似文献
569.
Transformation and regeneration of garlic (Allium sativum L.) by Agrobacterium-mediated gene transfer 总被引:5,自引:0,他引:5
By using highly regenerative calluses, we developed a stable transformation system in garlic (Allium sativum L.). The temperature and number of days of co-cultivation with Agrobacterium tumefaciens was shown to be an important factor in transient expression of the uid A gene. After a culture period of 5 months in selection medium containing hygromycin, 20 shoots were induced from ca. 1000
calluses, among which 15 plants expressed β-glucuronidase activity upon staining with X-Gluc. Shoots developed into transgenic garlic after 1 month. Integration of the uid A gene was confirmed by Southern blot analysis for genomic DNA of transgenic garlic plants.
Received: 25 October 1999 / Revision received: 16 February 2000 / Accepted: 22 February 2000 相似文献
570.
Abstract. Water permeability of cuticular membranes (CM) from the inner bulb scales of Allium cepa has been investigated. CM have a thickness ranging from 0.6 to 1.3 μm. They are composed of a thin (120–200 nm) lamellated cuticle proper and a thicker (300–900 nm) cuticular layer. Permeability coefficients for diffusion of water across these thin membranes are very low (4 × lO−10 ms−10 ). There was no difference in permeability of CM from successive scales of the same onion. Extraction of soluble cuticular lipids (SCL) with chloroform increased permeability by a factor of 1350 to 2050. Preliminary data indicate that only 1 μg cm−10 of SCL are removed by this treatment, hydrocarbons being the main (75%) consistuent. Permeability coefficients of cuticular transpiration were little affected by relative humidity, showing that transport is limited by a hydrophobic barrier that lacks dipoles. However, following extraction, permeability of the membranes depended strongly on humidity due to the presence of polar functional groups in the polymer matrix. Soluble cuticular lipids undergo a phase transition around 47°C. Temperatures higher than that irreversibly increased water permeability. 相似文献