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171.
Summary Unstable duplication and diploid strains of Aspergillus nidulans were treated with ethidium bromide, and it was shown that this drug reduces the number of sectors produced by such strains. The mechanisms which could be responsible for the partial stabilization of the strains are discussed and it is suggested that a similar mechanism is responsible for the production of sectors in both strains. It is also suggested that ethidium bromide could be useful for the reduction of instability of industrial strains.Acknowledgment. The authors are thankful to the National Council for the Development of Science and Technology (CNPq) for financial assistance. 相似文献
172.
Summary For 1 or 2 h following a gavage of milk or 300 mM CaCl2 (2 ml/100 g b.wt), rats had an increased liver calcium content when compared to rats receiving a deionized water gavage.Supported in part by a grant from the National Science Foundation (PCM 75-23603). We are grateful to Mr John O'Brien for his technical assistance. 相似文献
173.
Summary An increased release of acid phosphatase from the lysosomes of UVL irradiated hairless mouse epidermis is demonstrated. The results indicate that lysosomal membrane stability is decreased when the hairless mouse is exposed to either acute or chronic UVL.Acknowledgments. The authors would like to thank Miss Gail Brown for technical assistance. This research was supported in part by the Morrison Trust, San Antonio, Texas, and USPHS, grant CA-13464-04, from the NCI. 相似文献
174.
J. Mayo F. A. Carranza Jr. R. L. Cabrini 《Cellular and molecular life sciences : CMLS》1964,20(7):403-404
Zusammenfassung Es wurde der Einfluss von Antibiotica, von homologem Knochenmark und von Cysteamin in der Entwicklung der im Munde desMesocricetus aureatus durch totale Bestrahlung des Körpers produzierten nekrotischen Ulcera studiert. Es ergibt sich, dass bei den untersuchten Läsionen der bakterielle Faktor eine wichtige Rolle spielt. 相似文献
175.
Carver FM Shibley IA Pennington JS Pennington SN 《Cellular and molecular life sciences : CMLS》2001,58(4):645-652
The patterns of Glut1 and Glut3 glucose transporter protein and mRNA expression were assessed during embryogenesis of chicken
brain and skeletal muscle, Glut4 protein levels were also evaluated in skeletal muscle and heart, and Glut1 was examined in
the developing heart and liver. Glut1 protein expression was detectable throughout brain ontogeny but was highest during early
development. Glut1 mRNA levels in the brain remained very high throughout development. Glut3 protein was highest very early
and very late and mRNA was highest during the last half of development. In embryonic skeletal muscle, the levels of Glut1and
Glut3 proteins and mRNA were highest very early, and declined severely by mid-development. Glut1 protein and mRNA in the heart
also peaked early and then decreased steadily. Although Glut1 mRNA levels were consistently high in the embryonic liver, Glut1
protein expression was not detected. These results suggest that (1) Glut1 is developmentally regulated in chick brain, skeletal
muscle, and heart, (2) Glut1 mRNA is present in liver but does not appear to be translated, (3) Glut3 in brain increases developmentally
but is virtually absent in muscle, and (4) Glut4 protein and mRNA appear to be absent from chick heart and skeletal muscle.
Received 11 January 2001; accepted 14 February 2001 相似文献
176.
M. A. Hardy Jr. R. Montoreano M. Parisi 《Cellular and molecular life sciences : CMLS》1975,31(7):803-804
Resumen Los efectos de la ocitocina y la hipertonía serosa sobre la respuesta hidrosmótica de la vejiga urinaria del sapo pueden ser disociados empleando colchicina, y mas evidentemente cuando el alcaloide es colocado junto con Cu++. 相似文献
177.
A. A. Cossé M. G. Campbell T. J. Glover C. E. Linn Jr. J. L. Todd T. C. Baker W. L. Roelofs 《Cellular and molecular life sciences : CMLS》1995,51(8):809-816
In genetic studies on the sex pheromone communication system of two races of European corn borer, which use opposite pheromone blends of the E and Z compounds, it was found that antennal olfactory cell response amplitudes to the two compounds were controlled by an autosomal factor, whereas behavioral responses to the blends were controlled by a sex-linked locus. Because of the difference in genetic controls, it was postulated that some unusual males would be produced in F2 crosses between these two races. These unusual males would have antennal olfactory cells that respond as the Z-race males, but would respond behaviorally to the E blend. The present studies combined behavioral studies in a flight tunnel and single cell electrophysiological studies to show that these unusual males do indeed exist. These findings show that the spike amplitude of peripheral olfactory cells is not important in regulating species- or race-specific pheromone responses, as compared to some central nervous system factor assesses the spike frequencies from different pheromone-component-specific cells on the antenna. This factor seems to be essential in governing the pheromone-blend specific behavioral responses of male moths. 相似文献
178.
179.
E. D. Avner W. E. Sweeney Jr N. P. Piesco D. Ellis 《Cellular and molecular life sciences : CMLS》1986,42(1):77-80
Summary Cystic kidneys from the mutant CPK strain of C57BL/6J mice were cultured in serum-free organ culture. During 120 h of incubation in chemically-defined medium, CPK cystic tubular changes underwent complete regression. Environmental factors regulate the expression of genetically determined polycystic kidney disease in this model. 相似文献
180.