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91.
Sorbitol dehydrogenase genetics in the mouse: A ';null' mutant in a ';European' C57BL strain 总被引:1,自引:0,他引:1
A ';null' activity variant phenotype for sorbitol dehydrogenase (SDH) was observed in C57BL/LiA mice and used to examine the genetics of this enzyme. Linkage studies of the locus ( Sdh-1 ) with non-agouti (a) and a biochemical Iocus encoding liver L-α-hydroxyacid oxidase ( Hao-1 ) demonstrated that it is coincident with or closely linked to the structural locus, previously localized on chromosome 2. Alcohol dehydrogenase (ADH) isozymes were also examined, since the liver A2 isozyme exhibited some activity as a sorbitol dehydrogenase on cellulose acetate zymograms. It is apparent that SDH activity is not ';essential' in this mouse strain. 相似文献
92.
H. Nthel 《Mutation research》1981,84(2):291-304
In earlier work, immature oocytes of the irradiated population RÖI4 of Drosophila melanpgaster were found to be radioresistant relative to those of the basic population RÖI and to those of the control population Berlin wild (+K). The resistance of RÖI4 relative to RÖI was previously attributed to a hypothetical “factor” rar-3. In the present paper, evidence is presented to show that rar-3 is a single, recessive genetic factor, located on chromosome 3 at a map position of about 49.8. The action of rar-3 is apparently independent of that of rar-1 and rar-2, the factors already present in RÖI. 相似文献
93.
J.J.B. GILL A.J. CAIN 《Biological journal of the Linnean Society. Linnean Society of London》1980,14(3-4):293-301
The karyotypes of Cepaea nemoralis (L.) and C. hortensis (Müller), with 2n=44 and a conspicuously large pair of chromosomes, are described and compared with that of C. sylvatica (Draparnaud) which has 2n=50. The karyotype of C. sylvatica also has a conspicuously large pair of chromosomes but the comparison suggests that these have an independent origin from those in the 2n = 44 species. There is no evidence that the large chromosomes in C. nemoralis and C. hortensis have originated from simple fusion of chromosomes from a 2n=50 karyotype with chromosomes all sub-equal such as is reported for C. vindobonensis. It may be that such a karyotype with little size differentiation amongst the chromosomes is not a primitive feature in the Helicinae. The relationship of shell colour and banding polymorphism to the chromosome architecture is discussed. 相似文献
94.
Cytogenetic and electrophoretic analyses on 2n = 28 strains ofAsphodelus cerasiferus strongly suggest that the basic number x = 14 of the genusAsphodelus is of secondary polyploid origin from x = 7. 相似文献
95.
Intimate coupling of creatine phosphokinase and myofibrillar adenosinetriphosphatase 总被引:2,自引:0,他引:2
S P Bessman W C Yang P J Geiger S Erickson-Viitanen 《Biochemical and biophysical research communications》1980,96(3):1414-1420
ATPase and creatine phosphokinase (CPK) activities of isolated cardiac myofibrils were determined with 32P γ-labeled ATP alone and with the addition of phosphorylcreatine (PC). With ATP and PC as substrates the label in the inorganic phosphate formed is greatly diluted indicating that the ATP formed by PC through CPK can reach the ATPase active site more readily than labeled ATP from the medium. The tight coupling of the ATPase and CPK activities further strengthens our view that PC serves an important role as high energy carrier between the energy producing sites (mitochondria) and the energy utilizing sites (myofibrils). 相似文献
96.
J. J. Schneller 《Plant Systematics and Evolution》1979,132(4):255-277
In EuropeAthyrium filix-femina has a constant chromosome number (2n = 80) and is sexual. The normal type of reproduction is intergametophytic crossing. In the gametophyte phase there is a hormone system which induces dark germination of spores and antheridium formation. Sporophytes originating from single prothalli show that a genetic load is present in all population examined. It appears not to be a simple allelic load but a complicated balanced system. Morphological variability can be interpreted as the expression of the genetic heterogeneity of populations. There are no crossing barriers, not even between insular populations hundreds of kilometers apart. 相似文献
97.
An electrophoretic variant of the X-linked enzyme phosphoglycerate kinase (PGK-1) has been used to study regulation of X chromosome expression in the diploid derivatives of the trophectoderm at 8–8.5 days post coitum in the mouse. These derivatives included the chorionic ectoderm and the polar trophoblast. The biochemical analysis suggests that only the maternally derived X chromosome (Xm) is expressed in the diploid trophectoderm derivatives. Cell selection and maternal tissue contamination were ruled out as possible causes of the observed Xm expression. From these and other results, we conclude that all derivatives of the trophectoderm, along with the primitive endoderm, express only Xm, whereas derivatives of the primitive ectoderm show random X chromosome expression. 相似文献
98.
Assignment of the gene for dipeptidase 2 to Mus musculus chromosome 18 by somatic cell hybridization
Evidence is presented for the assignment of the gene for dipeptidase 2 to Mus musculus chromosome 18 by synteny testing and karyotypic analysis of Chinese hamster × mouse somatic cell hybrid clones. DIP-2 and chromosome 18 were expressed concordantly in 24/24 clones examined (ten primary clones and 14 secondary clones). Synteny testing indicated that DIP-2 was not expressed concordantly with the expression of any marker enzymes.This work was supported by NIH grant USPHS GM 09966. 相似文献
99.
Evidence is presented for the assignment of the gene for glyoxylase I to mouse chromosome 17 using mouse × Chinese hamster somatic cell hybrids. GLO I was not expressed concordantly with any known marker enzymes which represented 11 linkage groups. The presence of chromosome 17 and expression of GLO I were concordant in 31/31 clones. GLO I is thus linked to the H-2 histocompatibility locus in the mouse. 相似文献
100.
A mutant form of erythrocyte hypoxanthine-guanine phosphoribosyltransferase with an abnormal isoenzyme pattern was found in a patient with a partial enzyme deficiency and X-linked gout. This abnormal pattern was a marker for the mutant enzyme in hemolysate from the heterozygote for the enzyme deficiency.These studies were generously supported by the Medical Research Council of Canada (MRC # MA4758) and the Canadian Arthritis and Rheumatism Society. 相似文献