Relations with South Africa     

Hoffman J 《Science (New York, N.Y.)》1971,173(4000):868

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THE ORGANIZATION OF KNOWLEDGE     

Hoffman FL 《Science (New York, N.Y.)》1922,55(1420):279-284

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Progress toward malaria preerythrocytic vaccines   总被引：5，自引：0，他引：5  

S L Hoffman  V Nussenzweig  J C Sadoff  R S Nussenzweig 《Science (New York, N.Y.)》1991,252(5005):520-521

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Welfare dependence within and across generations   总被引：2，自引：0，他引：2  

G J Duncan  M S Hill  S D Hoffman 《Science (New York, N.Y.)》1988,239(4839):467-471

A central question in the debate about the effects of welfare programs is whether their intended positive results--providing needed resources to recipients and their children--outweigh any unintended negative results--for example, the breaking up of families, reduction in work effort, or the fostering of a welfare "culture" that is passed on from parent to child. Recent research shows that although work effort is affected adversely by the generosity of welfare programs, effects on family structure appear quite weak, most welfare experiences are relatively short, and the majority of women who grew up in homes heavily dependent on welfare do not rely on those programs when they are young adults.  相似文献   

Chemical Feeding Deterrent Mobilized in Response to Insect Herbivory and Counteradaptation by Epilachna tredecimnotata     

Carroll CR  Hoffman CA 《Science (New York, N.Y.)》1980,209(4454):414-416

Experimentally damaged leaves of Cucurbita moschata mobilize substances to the damaged region within 40 minutes. These substances stimulate feeding by Acalymma vittata (Coleoptera: Chrysomelidae) and inhibit feeding by Epilacha tredecimnotata (Coleoptera: Coccinelidae). Under natural conditions, Epilachna cuts a circular trench in the leaf before feeding on the encircled leaf material, thus preventing mobilization of the deterrent substances to the feeding area.  相似文献   

Punctuated equilibrium and the fossil record     

Schopf TJ  Hoffman A 《Science (New York, N.Y.)》1983,219(4584):439-440

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Naturally acquired antibodies to sporozoites do not prevent malaria: vaccine development implications   总被引：12，自引：0，他引：12  

S L Hoffman  C N Oster  C V Plowe  G R Woollett  J C Beier  J D Chulay  R A Wirtz  M R Hollingdale  M Mugambi 《Science (New York, N.Y.)》1987,237(4815):639-642

The first human vaccines against the malaria parasite have been designed to elicit antibodies to the circumsporozoite protein of Plasmodium falciparum. However, it is not known whether any level of naturally acquired antibodies to the circumsporozoite protein can predict resistance to Plasmodium falciparum malaria. In this study, 83 adults in a malaria-endemic region of Kenya were tested for circumsporozoite antibodies and then treated for malaria. They were monitored for the development of new malaria infections for 98 days. Antibody levels, as determined by four assays in vitro, were indistinguishable between the 60 individuals who did and the 23 who did not develop parasitemia during follow-up, and there was no apparent relation between day of onset of parasitemia and level of antibodies to circumsporozoite protein. Unless immunization with sporozoite vaccines induces antibodies that are quantitatively or qualitatively superior to the circumsporozoite antibodies in these adults, it is unlikely that such antibodies will prevent infection in areas with as intense malaria transmission as western Kenya.  相似文献   

Uronic Acid of Chondroitin Sulfate B     

Hoffman P  Linker A  Meyer K 《Science (New York, N.Y.)》1956,124(3234):1252-1253

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Human acid phosphatase in somatic cell hybrids   总被引：3，自引：0，他引：3  

G A Bruns  P S Gerald 《Science (New York, N.Y.)》1974,184(135):480-482

The human enzyme, lysosomal acid phosphatase ACP2, is expressed in nan-rodent somatic cell hybrids as a dimeric molecule. The human-rodent heteropolymer, as well as the human and rodent homopolymer, is associated with lysosomes in these cells. The genes specifying lysosomal acid phosphatase ACP(2) and LDH A are syntenic.  相似文献   

Genetic restriction of energy conservation in Schizophyllum   总被引：2，自引：0，他引：2  

R M Hoffman  J R Raper 《Science (New York, N.Y.)》1971,171(969):418-419

A genetically determined malfunction of energy conservation reduces assimilation of substrate to half or less its normal level while leaving oxidative processes apparently unchanged. This metabolic defect, which differs in many ways from any previously described, is related to the function of the B incompatibility factor and occurs both in the common A heterokaryon (A = B not equal)-in which two compatible, wild B factors interact-and in mutant-B homokaryons.  相似文献