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991.
JENS ERIKJELNES 《Zoological Journal of the Linnean Society》1986,87(1):1-26
Horizontal starch gel electrophoresis was used to score mobilities of seven different enzymes in species of Bulinus from North and West Africa. An account of the intra- and inter-population variation observed was given. Based on the data obtained it was suggested that enzymic data should be used as taxonomic characters in parallel with morphological and anatomical characters. It is suggested that enzymic characters could be used to place taxa into synonymy if the data are collected in such a way that one can write up an enzyme profile for the single individual. The nine taxa of Bulinus known to occur in North and West Africa were revised, the taxon B. jousseaumei was synonymized with B. globosus , and the two taxa B. guernei and B. rohlfsi were synonymized with B. truncatus. As a result of the revision only six species could be recognized as valid from the area, these being B. forskalii, B. globosus, B. senegalensis, B. truncatus, B. ugandae and B. umbilicatus. Finally, some enzymic characters are suggested that may be used for a reliable identification of these morphologically very difficult taxa. 相似文献
992.
Summary Identification ofRhizobium trifolii strains using intrinsic antibiotic resistance and serology was performed. Unknown strains, generated by mixing known strains
in a common broth, always reacted with only one antiserum but showed variable intrinsic antibiotic resistance patterns. All
unknowns were rapidly and unambiguously identified by the immunological double diffusion technique, while 33% of the unknowns
were either unidentifiable or identified incorrectly when resistance to various antibiotics was measured. It is concluded
that serology is less variable than instrinsic antibiotic resistance when strains ofR. trifolii are identified. 相似文献
993.
The common short-bodied species of Bipalium does not fragment, but individuals of two newly discovered long-bodied species — B. nobile Kawakatsu & Makino, 1982, and B. multilineatum Makino & Shirasawa, 1983 — do regularly fission, usually behind the mouth or genital pore. Some experimental regenerates of these species form rings by adhesion of the anterior with the posterior cut surface. We found two other forms of Bipalium, perhaps representing a further two species, in Hino City, Tokyo, in 1983; and we have preliminarily arranged the forms of Bipalium known in the region into four groups distinguished on the basis of body coloring, position of the mouth, and structure of the copulatory organ. 相似文献
994.
995.
Michael G. Gabridge Daniel J. Lundin Martha F. Gladd 《In vitro cellular & developmental biology. Plant》1986,22(8):491-498
Summary An enzyme-linked immunosorbent assay (ELISA) was developed in order to serve in detecting and speciating mycoplasmas isolated
from cell cultures. Its main features included a biotin-streptavidin amplification step and a solid phase consisting of a
microporous membrane. Cell samples in the form of suspensions were applied to nitrocellulose or ion exchange membranes immobilized
in commerciallyavailable microtiter, multiwell manifolds. The blocking buffer contained 1% purified α-casein. The primary
antibodies were monoclonal and the polyclonal secondary antibody was biotinylated. The enzyme utilized was streptavidin-horseradish
peroxidase. The substrate-dye complex consisted of either 4-chloro-1-naphthol and hydrogen peroxide or ortho phenylene diamine
(OPD) and hydrogen peroxide. The presence of homologous antiserum in the reaction sequence gave clearly visible, colored reactions
on the membrane when 50 ul with approximately 105 or more cfu/ml were present. This new biotin-avidin microporous membrane (BAMM-ELISA) test can be used both to detect mycoplasmas
and to speciate them. The BAMM-ELISA is simple, rapid, sensitive, specific and economical. As such, it has potential for aiding
in the control of mycoplasma contamination in cell culture, and could prove useful in clinical diagnostic applications as
well.
This study was supported in part by Bionique Laboratories, Inc., and research grants awarded by the National Institutes of
Health (SBIR Phase II from NIEHS, R44ES03705) and the New York State Science and Technology Foundation (SSF 84-1). Valuable
technical assistance and counsel were provided by Dr. Steven Geary, Angela Alongi and Alexandria Siy. Photography was done
through the courtesy of Marina LaDuke of the W. Alton Jones Cell Science Center. 相似文献
996.
Multiple forms of peroxidase from Narcissus pseudonarcissus were identified and separated by polyacrylamide gel electrophoresis. The enzyme forms were found to be particulate but could be solubilized in buffers of high ionic strength and high pH. Bulbs at different stages (dormant, early growth, flowering and post-flowering) were investigated and both the number and distribution of peroxidase forms were found to differ. The major peroxidase form in dormant bulbs was purified and displayed a number of notable properties including a MW of at least 105, a high isoelectric point and the apparent absence of a heme prosthetic group. 相似文献
997.
Identification of broccoli and cauliflower cultivars with RAPD markers 总被引:43,自引:0,他引:43
Summary RAPD (Random Amplified Polymorphic DNA) markers generated by 4 arbitrary 10-mer primers, discriminated 14 broccoli and 12 cauliflower cultivars (Brassica oleracea L.) by banding profiles. The size of the amplified DNA fragments ranged from 300 to 2600 base pairs. Twenty-eight percent of the markers were fixed in both broccoli and cauliflower, whereas 12.5% were specific to either crop. The rest were polymorphic in either or both crops. The markers generated by two and three primers were sufficient to distinguish each of the broccoli and cauliflower cultivars, respectively. The average difference in markers was 14.5 between broccoli and cauliflower markers, 5.8 between two broccoli cultivars and 7.9 between two cauliflower cultivars. Larger differences for each crop were found between cultivars from different seed companies than within the same company. RAPD markers provide a quick and reliable alternative to identify broccoli and cauliflower cultivars. 相似文献
998.
David A. Carlson Susan K. Milstrey 《Archives of insect biochemistry and physiology》1991,16(3):165-175
Comparison of the presence and quantities of cuticular hydrocarbons has been used successfully for identifying sibling species and races of several groups of insects. This approach has been extended to four species of moths previously regarded as belonging to the same genus, Heliothis. Gas chromatography was used to quantify the numerous high-molecular weight alkanes found on the cuticle of two pairs of closely related species: Helicoverpa zea and Helicoverpa armigera, and Heliothis virescens and Heliothis subflexa. Both sexes of H. zea and H. armigera contained different quantities of several alkanes that could be used for unambiguous identification. Similar comparisons of H. subflexa and H. virescens showed four peak ratios that were different for each species. Sexual dimorphism was minor in H. subflexa and H. virescens. 相似文献
999.
DNA probes for species identification of mosquitoes in the Anopheles gambiae complex 总被引:1,自引:0,他引:1
Abstract. Identification of species within the Anopheles gambiae Giles species complex is essential for the correct evaluation of malaria vector ecology studies and control programmes. The development of DNA probes to distinguish species of the An.gambiae complex is described. Genomic libraries were prepared for four members of the An.gambiae complex. These were screened using radiolabeled DNA from different species of An. gambiae sensu lato and a number of clones selected on the basis of their species specificity. These clones could be divided into two groups, each containing homologous sequences. Sequences homologous to group 1 inserts are highly reiterated in the genomes of Anopheles arabiensis Patton and Anopheles merus Dönitz, present in low copy number in Anopheles melas Theobald, but were not detected in Anopheles gambiae sensu stricto. Studies on the organization of this sequence in the genome of An.arabiensis show that homologous sequences are male specific and interspersed within the chromatin. Sequences homologous to group 2 inserts are highly repeated in the genomes of An.merus and An.melas, but present in low copy number in An.gambiae s.s. and An.arabiensis. Group 2 homologous sequences are not sex-specific in the species tested and appear to be tandemly repeated. When used as hybridization probes, these sequences provide a sensitive means for the identification of species within the Anopheles gambiae complex. 相似文献
1000.
Use of a male-specific DNA probe to distinguish female mosquitoes of the Anopheles gambiae species complex 总被引:1,自引:0,他引:1
Abstract. A method has been developed to distinguish between mated female individuals of the sibling species Anopheles gambiae Giles sensu stricto and Anopheles arabiensis Patton. The DNA probe pAnal, reported by Gale & Crampton (1987a) to be useful for the specific identification of An.arabiensis males, is here shown to be sufficiently sensitive to deduce the species identity of inseminated females from the identity of the sperm contained within the spermatheca. 相似文献