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941.
Michael Ludwig Bonnie Ching Heiko Reutter Simeon A. Boyadjiev 《Birth defects research. Part A, Clinical and molecular teratology》2009,85(6):509-522
The bladder exstrophy‐epispadias complex (BEEC) represents an anterior midline defect with variable expression comprising a spectrum of anomalies involving the abdominal wall, pelvis, urinary tract, genitalia, and occasionally the spine and anus. The vast majority of BEEC cases are classified as non‐syndromic and the etiology of this malformation is still unknown. This review presents the current state of knowledge on this multifactorial disorder, including historical retrospect, phenotypic and anatomical characterization, epidemiology, proposed developmental mechanisms, existing animal models, and implicated genetic and environmental components. These published lines of evidence argue strongly that BEEC occurs as a result of strong genetic predisposition that is yet to be deciphered. Birth Defects Research (Part A), 2009. © 2009 Wiley‐Liss, Inc. 相似文献
942.
Melinda Bonnie Fagan 《Journal of the history of biology》2010,43(1):67-109
This essay examines the role of social interactions in the search for blood stem cells, in a recent episode of biomedical
research. Linked to mid-20th century cell biology, genetics and radiation research, the search for blood stem cells coalesced
in the 1960s and took a developmental turn in the late 1980s, with significant ramifications for immunology, stem cell and
cancer biology. Like much contemporary biomedical research, this line of inquiry exhibits a complex social structure and includes
several prominent scientific successes, recognized as such by participating researchers. I use personal interviews and the
published record to trace the social interactions crucial for scientific success in this episode. All recognized successes
in this episode have two aspects: improved models of blood cell development, and new interfaces with other lines of research.
The narrative of the search for blood stem cells thus yields a robust account of scientific success in practice, which generalizes
to other scientific episodes and lends itself to expansion to include wider social contexts. 相似文献
943.
Immunogenicity of heterologous recombinant adenovirus prime-boost vaccine regimens is enhanced by circumventing vector cross-reactivity
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Thorner AR Lemckert AA Goudsmit J Lynch DM Ewald BA Denholtz M Havenga MJ Barouch DH 《Journal of virology》2006,80(24):12009-12016
The high prevalence of preexisting immunity to adenovirus serotype 5 (Ad5) in human populations has led to the development of recombinant adenovirus (rAd) vectors derived from rare Ad serotypes as vaccine candidates for human immunodeficiency virus type 1 and other pathogens. Vaccine vectors have been constructed from Ad subgroup B, including rAd11 and rAd35, as well as from Ad subgroup D, including rAd49. However, the optimal combination of vectors for heterologous rAd prime-boost vaccine regimens and the extent of cross-reactive vector-specific neutralizing antibodies (NAbs) remain poorly defined. We have shown previously that the closely related vectors rAd11 and rAd35 elicited low levels of cross-reactive NAbs. Here we show that these cross-reactive NAbs correlated with substantial sequence homology in the hexon hypervariable regions (HVRs) and suppressed the immunogenicity of heterologous rAd prime-boost regimens. In contrast, vectors with lower hexon HVR homology, such as rAd35 and rAd49, did not elicit detectable cross-reactive vector-specific NAbs. Consistent with these findings, rAd35-rAd49 vaccine regimens proved more immunogenic than both rAd35-rAd5 and rAd35-rAd11 regimens in mice with anti-Ad5 immunity. These data suggest that optimal heterologous rAd prime-boost regimens should include two vectors that are both rare in human populations to circumvent preexisting antivector immunity as well as sufficiently immunologically distinct to avoid cross-reactive antivector immunity. 相似文献
944.
Bonnie Urciuoli 《American anthropologist》1998,100(3):799-800
Worlds of Talk: The Presentation of Self in Everyday Conversation. Martin J. Malone. Maiden, MA: Blackwell Publishers. 1997.182pp. 相似文献
945.
946.
Within the cerebellum calmodulin mRNA is found predominantly in Purkinje cells, with lower levels in granule cells and interneurons. The message shows developmental increases during the first 14 days postnatally. Surviving Purkinje cells of the staggerer (sg/sg) mutant, which are grossly stunted and lack tertiary dendritic spines, contain no detectable calmodulin mRNA, as assayed by Northern blot or an enhanced biotinylated in situ hybridization. This is in contrast to both the Lurcher Purkinje cells and sg/sg granule cells, which express normal levels of this mRNA up until the time they disappear. The sg/sg phenotype can be explained by a defective Purkinje-cell-specific regulatory mechanism for calmodulin. 相似文献
947.
Anthropological theories of population growth in underdeveloped countries are considered and it is argued that most studies have concentrated exclusively on either deterministic or self-regulatory factors in population growth without regard to their probable interaction. A research strategy is proposed in which self-regulatory factors, especially the decision-making activities of individual parents, provide a primary focus of study but with careful attention to deterministic factors which constrain and influence the decision process . [population, underdevelopment, biology and self-regulation in population theory] 相似文献
948.
Bonnie Miller David L. Nelson Fred R. Butcher 《Biochimica et Biophysica Acta (BBA)/General Subjects》1979,587(3):446-454
Carbachol and substance P stimulated 45Ca2+ flux changes, 86Rb+ efflux, and amylase secretion from acinar cells isolated fromrat parotid. The local anesthetic tetracaine blocked all of these measured responsed to carbachol, but none of the responses to substance P. Tetracaine must act at either the cholinergic receptor or at a subsequent transducing step in the cholinergic stimulus-response sequence. If tetracaine acts at one of the transducing steps between cholinergic receptor occupation and the physiological responses then the action of tetracaine must be at a locus in the cholinergic reaction scheme not shared by substance P, because tetracaine did not block any response of the parotid to substance P. 相似文献
949.