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Measuring Gender     
Over the past several years, various operational definitions of gender have been used in studies of gender conformity in homosexual males. The goal of these studies is to demonstrate that childhood gender nonconformity (CGN) is either the proximate cause of adult homosexuality or an intermediate step in a biologically mediated process. The hypothesis of a causal connection between the development of gender and sexual orientation is embedded within the context of a biological (evolutionary) understanding of human behavior. Thus, testing the hypothesis of a causal connection between CGN and sexuality requires a concept of gender that is compatible with the basic principles of biological causation and our current understanding of evolutionary processes. I will argue that the concepts of gender used in the attempt to demonstrate a causal connection between CGN and sexual orientation are inappropriate because they provide no uniform, consistent method for identifying and measuring the biologically significant components of gender. I will also argue that the concept of gender that does emerge from these studies suggests an hypothesis about the connection between sexuality and gender that is not consistent with the cross-gendered theory of the etiology of homosexuality.  相似文献   
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Incorporation of the DNA-cleaving moiety EDTA.Fe at discrete amino acid residues along a DNA-binding protein allows the positions of these residues relative to DNA bases, and hence the organization of the folded protein, to be mapped by high-resolution gel electrophoresis. A 52-residue protein, based on the sequence-specific DNA-binding domain of Hin recombinase (139-190), with EDTA at the NH2 terminus cleaves DNA at Hin recombination sites. The cleavage data for EDTA-Hin(139-190) reveal that the NH2 terminus of Hin(139-190) is bound in the minor groove of DNA near the symmetry axis of Hin-binding sites [Sluka, J. P., Horvath, S. J., Bruist, M. F., Simon, M. I., & Dervan, P. B. (1987) Science 238, 1129]. Six proteins, varying in length from 49 to 60 residues and corresponding to the DNA-binding domain of Hin recombinase, were synthesized by solid-phase methods: Hin(142-190), Hin(141-190), Hin(140-190), Hin(139-190), Hin(135-190), and Hin(131-190) were prepared with and without EDTA at the NH2 termini in order to test the relative importance of the residues Gly139-Arg140-Pro141-Arg142, located near the minor groove, for sequence-specific recognition at five imperfectly conserved 12-base-pair binding sites. Footprinting and affinity cleaving reveal that deletion of Gly139 results in a protein with affinity and specificity similar to those of Hin(139-190) but that deletion of Gly139-Arg140 affords a protein with altered affinities and sequence specificities for the five binding sites. It appears that Arg140 in the DNA-binding domain of Hin is important for recognition of the 5'-AAA-3' sequence in the minor groove of DNA. Our results indicate modular DNA and protein interactions with two adjacent DNA sites (major and minor grooves, respectively) bound on the same face of the helix by two separate parts of the protein.  相似文献   
185.
Metabolic, temperature, and cardiorespiratory responses of 19 healthy males, age range 18-30 yr for one group and 40-55 yr for another, were studied during 210 minutes submaximal work at 35% Vo2 max. The subjects were exposed to four different pollutant gas mixtures at two different temperatures, 25 degrees C and 35 degrees C (relative humidity 30%). The four gas mixtures were filtered air (FA), 50 ppm carbon monoxide in filtered air (CO), 0.24 ppm peroxyacetyl nitrate in filtered air (PAN), and a combination of all three mixtures (PANCO). In the CO exposure, the heart rate was significantly greater than that observed during FA conditions (P less than 0.05). Metabolic and thermoregulatory responses to long-term work were not different in the various pollutant environments. Significant decreases in stroke volume and increases in heart rate were observed during the course of the 25 degrees C exposures with no alteration in cardiac output. Heart rates were higher during 35 degrees C exposures while cardiac output remained at the same level with a consequent further reduction in stroke output.  相似文献   
186.
A method is described for frequent sequential blood volume estimation in baboons using 32P for red cell volume measurements and 125I-albumin for simultaneous plasma volume measurements. Values for red cell, plasma, and total blood volumes are reported. Close correlations of the volumes to bodyweight were demonstrated. Circulatory half-lives of the isotopes, determined from disappearance curves, confirmed their suitability for serial measurements in these baboons.  相似文献   
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International Journal of Peptide Research and Therapeutics - Bacterial adhesion is a crucial event of intestinal pathological conditions evoked by bacterial infections. Pituitary adenylate cyclase...  相似文献   
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