PIPETTING DEVICE FOR DISINFECTANT TESTING     

Jacobson S  Prindle B 《Science (New York, N.Y.)》1936,83(2147):191-192

  相似文献   

Heritable somatic excision of a Drosophila transposon   总被引：9，自引：0，他引：9  

G J Bryan  J W Jacobson  D L Hartl 《Science (New York, N.Y.)》1987,235(4796):1636-1638

A mutation in the white gene of Drosophila mauritiana that results from insertion of the transposable element mariner is genetically unstable in both germ cells and somatic cells. Somatic instability is indicated by the occurrence of animals having mosaic eyes with patches of pigmented cells on a peach-colored background. Normally uncommon, the frequency of mosaicism is so greatly enhanced in a particular mutant strain that virtually every animal in the strain is an eye-color mosaic. The molecular basis of the mosaicism is the excision of the mariner element from its location in the DNA of the white gene in somatic cells. The phenomenon results from a single dominant genetic factor located in chromosome 3. Genetic control over the excision of transposable elements may play a role in determining the persistence of transposable elements in the genome.  相似文献   

A protein induced during nerve growth (GAP-43) is a major component of growth-cone membranes   总被引：24，自引：0，他引：24  

J H Skene  R D Jacobson  G J Snipes  C B McGuire  J J Norden  J A Freeman 《Science (New York, N.Y.)》1986,233(4765):783-786

Growth cones are specialized structures that form the distal tips of growing axons. During both normal development of the nervous system and regeneration of injured nerves, growth cones are essential for elongation and guidance of growing axons. Developmental and regenerative axon growth is frequently accompanied by elevated synthesis of a protein designated GAP-43. GAP-43 has now been found to be a major component of growth-cone membranes in developing rat brains. Relative to total protein, GAP-43 is approximately 12 times as abundant in growth-cone membranes as in synaptic membranes from adult brains. Immunohistochemical localization of GAP-43 in frozen sections of developing brain indicates that the protein is specifically associated with neuropil areas containing growth cones and immature synaptic terminals. The results support the proposal that GAP-43 plays a role in axon growth.  相似文献   

A 50,000-year record of climate oscillations from Florida and its temporal correlation with the heinrich events     

Grimm EC  Jacobson GL  Watts WA  Hansen BC  Maasch KA 《Science (New York, N.Y.)》1993,261(5118):198-200

Oscillations of Pinus (pine) pollen in a 50,000-year sequence from Lake Tulane, Florida, indicate that there were major vegetation shifts during the last glacial cycle. Episodes of abundant Pinus populations indicate a climate that was more wet than intervening phases dominated by Quercus (oak) and Ambrosia-type (ragweed and marsh-elder). The Pinus episodes seem to be temporally correlated with the North Atlantic Heinrich events, which were massive, periodic advances of ice streams from the eastern margin of the Laurentide Ice Sheet. Possible links between the Tulane Pinus and Heinrich events include hemispheric cooling, the influences of Mississippi meltwater on sea-surface temperatures in the Gulf of Mexico, and the effects of North Atlantic thermohaline circulation on currents in the Gulf.  相似文献   

Brain enhancement in tadpoles: increased DNA concentration after somatotrophin or prolactin     

R K Hunt  M Jacobson 《Science (New York, N.Y.)》1970,170(955):342-344

Frog tadpoles, injected with prolactin or somatotrophin during early stages when the brain cell population is rapidly increasing, exhibited marked increases over sham-injected controls in body weight, brain weight, and brain DNA, throughout subsequent development. Animals treated with somatotrophin attained the increase in brain DNA during the infection period. Prolactin had little effect during this period, but brain DNA accumulation continued at an accelerated rate over the next 15 days, when the rate of DNA increment normally declined. Patterns of incorporation of tritiated thymidine confirmed that both hormones increased DNA accumulation, suggesting increased cell proliferation rather than decreased cell death.  相似文献   

Isolation of N,N-Diethyl-m-toluamide (Deet) from Female Pink Bollworm Moths     

Jones WA  Jacobson M 《Science (New York, N.Y.)》1968,159(3810):99-100

A chemical search for a natural activator of propylure, the sex pheromone of the pink bollworm moth, revealed that the female moths produce N,N-diethyl-m-toluamide, an outstanding insect repellent synthesized commercially and never before reported from natural sources. The compound occurs in fairly large amount in female adults and in much lesser amount in female pupae, but it is completely absent in female larvae and in all stages of the male insect. Its role in the life of the insect has not yet been definitely determined.  相似文献   

Sex attractant of the pink bollworm moth: isolation, identification, and synthesis     

Jones WA  Jacobson M  Martin DF 《Science (New York, N.Y.)》1966,152(3728):1516-1517

The sex attractant produced in extremely small amount by the virgin female pink bollworm moth has been isolated in pure form and identified as 10-propyl-trans- 5, 9-tridecadienyl acetate. Successful synthesis of this molecule confirms the structure and makes possible its practical use to help control this destructive pest of cotton. The attractant, for which the common name "propylure" is suggested, may be the first naturally occurring compound with propyl branching to be reported.  相似文献   

Ecology. Ecology for a crowded planet     

Palmer M  Bernhardt E  Chornesky E  Collins S  Dobson A  Duke C  Gold B  Jacobson R  Kingsland S  Kranz R  Mappin M  Martinez ML  Micheli F  Morse J  Pace M  Pascual M  Palumbi S  Reichman OJ  Simons A  Townsend A  Turner M 《Science (New York, N.Y.)》2004,304(5675):1251-1252

  相似文献   

Burgeoning ABM Costs     

Jacobson BS 《Science (New York, N.Y.)》1967,158(3802):718

  相似文献   

THE IMPORTANCE OF SCIENTIFIC RESEARCH TO THE INDUSTRIES     

Jacobson CA 《Science (New York, N.Y.)》1916,44(1135):456-459

  相似文献