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41.
A. Theodore Steegmann Jr. 《American anthropologist》1994,96(3):723-725
Social and Biological Aspects of Ethnicity . Malcolm Chapman , ed.
The Anthropology of Disease . C. G. N. Mascie-Taylor , ed. 相似文献
The Anthropology of Disease . C. G. N. Mascie-Taylor , ed. 相似文献
42.
The human glucagon receptor encoding gene: structure, cDNA sequence and chromosomal localization 总被引:2,自引:0,他引:2
Si Lok Joseph L. Kuijper Laura J. Jelinek Janet M. Kramer Theodore E. Whitmore Cindy A. Sprecher Shannon Mathewes Francis J. Grant Shaula H. Biggs Gary B. Rosenberg Paul O. Sheppard Patrick J. O''Hara Donald C. Foster Wayne Kindsvogel 《Gene》1994,140(2):203-209
Characterization of the human glucagon-receptor-encoding gene (GGR) should provide a greater understanding of blood glucose regulation and may reveal a genetic basis for the pathogenesis of diabetes. A cDNA encoding a complete functional human glucagon receptor (GGR) was isolated from a liver cDNA library by a combination of polymerase chain reaction and colony hybridization. The cDNA encodes a receptor protein with 80% identity to rat GGR that binds [125I] glucagon and transduces a signal leading to increases in the concentration of intracellular cyclic adenosine 3′,5′-monophosphate. Southern blot analysis of human DNA reveals a hybridization pattern consistent with a single GGR locus. In situ hybridization to metaphase chromosome preparations maps the GGR locus to chromosome 17q25. Analysis of the genomic sequence shows that the coding region spans over 5.5 kb and is interrupted by 12 introns. 相似文献
43.
The snare web is used as a medium for communication betweenindividuals within colonies of social spiders and has thereforebeen suggested as necessary for the evolution of sociality inthe Araneae. The social spider Diaea socialis (Thomisidae) isan exception because it does not build a snare web. Experimentsdemonstrate that silk attracts all spiders and that a chemicaldeposited onto the silk attracts adult female spiders, suggestingthat the group living of this species is mediated by a pheromone.The pheromone attracts spiders differentially: females are notattracted to juvenile silk, and it repels gravid females. Thepheromone appears to be stable but volatile, is ether-soluble,and retains its viability after dissolution. Molecular-ionicmasses for 7-8 different compounds were found in the range 220281atomic units; the pheromone may be one or a combination of severalof these. 相似文献
44.
Catherine A. Vandevoort Laurie E. Neville Theodore L. Tollner Leslie P. Field 《Zoo biology》1993,12(3):257-265
Preservation of the genetic diversity of the captive orangutan, especially the wild-caught founders, is critical in maintaining a long-term population in zoological parks. One solution to the problem of maintaining maximum genetic diversity would be to initiate a program of artificial insemination for genetically underrepresented individuals through the banking and interinstitutional use of cryopreserved semen. However, little is known about basic orangutan semen characteristics, and current methodology is inadequate to support such a program. In this paper, we report the results of semen collection from an adult Sumatran orangutan (Pongo pygmaeus abelli), using an artificial vagina without anesthesia or electrical stimulation. A total of 27 ejaculates were evaluated during a 1-year period. The total and liquid volumes of the ejaculates at 1 h following collection were 6.1 ± 0.6 ml and 2.6 ± 0.4 ml, respectively (mean ± SEM). The liquid portion continued to exude semen for 2 h; however, 90% of the motile sperm was exuded within the first 30 min. The total number of sperm in the ejaculate was 164 ± 106 ± 16.5, and the percentage of motile cells was 60 ± 2.7%. We conclude that the artificial vagina provides a promising technique for semen collection in the orangutan, and view these results as an initial step in developing methods for in vitro sperm capacitation, sperm cryopreservation, and artificial insemination. © 1993 Wiley-Liss, Inc. 相似文献
45.
Mark Goodman Ph.D. Theodore M. Dembroski Jeffrey H. Herbst 《Applied psychophysiology and biofeedback》1996,21(3):207-216
The purpose of this study was to determine the minimum number of consecutive blood pressure cuff inflations required to obtain seated stable resting baseline measurements of heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP). Sixty male college students aged 18 to 31 years volunteered as study subjects. Thirteen observations of HR, SBP, DBP, and MAP were recorded at 90-second intervals for each subject using a Critikon-Dinamap monitor. Stable readings for SBP and MAP were obtained in 6.5 minutes or 3 to 5 cuff inflations in the population tested. Using this procedure, additional age- and gender-specific norms could be established for normal and hypertensive subjects. Knowing the approximate quantity and frequency of blood pressure cuff inflations needed to generate baseline minimum measurements of HR, SBP, DBP, and MAP will be helpful in studies of cardiovascular reactivity, as well as for clinical and psychophysiologic treatment of hypertension. 相似文献
46.
47.
George V. Triantaphyllidis Godelieve R. J. Criel Theodore J. Abatzopoulos Patrick Sorgeloos 《Hydrobiologia》1997,357(1-3):155-163
Eleven morphometric and one meristic character in 15 parthenogeneticArtemia populations have been studied by using discriminant andcluster analysis as well as scanning electron microscopy.Discriminant analysis revealed five main groups of morphologicalpatterns: (i) the coastal Chinese populations together with apopulation from Kazakhstan, (ii) the inland Chinese salt lakepopulations, (iii) the Greek populations, (iv) one African populationfrom Namibia and (v) a Chinese population from Xuyu (Jiangsuprovince). Cluster analysis was not always in agreement withdiscriminant analysis and these results are discussed. 相似文献
48.
Krishna P. Kollipara Ram J. Singh Theodore Hymowitz 《American journal of botany》1995,82(9):1104-1111
We investigated the use of a monoclonal antibody (MAb 238) to the soybean Bowman-Birk inhibitor (BBI) to verify and understand the intergenomic relationships among the wild perennial Glycine species. Competitive enzyme linked immunosorbent assay and western blot screening studies revealed that the accessions of B-genome (G. latifolia, G. microphylla, and G. tabacina, 2n = 40) and C-genome (G. curvata and G. cyrtoloba) species did not contain the MAb 238 crossreactive proteins (BBI-nulls). By contrast, all the A-genome (G. argyrea, G. canescens, G. clandestina, and G. latrobeana), E-genome (G. tomentella, 2n = 38), and F-genome (G. falcata) species, G. arenaria (genome unknown), and the polyploid (2n = 78,80) G. tomentella accessions were BBI-positive. The D-genome G. tomentella (2n = 40) and tetraploid G. tabacina (2n = 80) contained both BBI-null and BBI-positive type accessions. Among the recently described species, G. hirticaulis (2n = 40), G. lactovirens, and G. pindanica contained the MAb 238 crossreactive proteins while G. albicans did not. Glycine hirticaulis, G. pindanica, and G. tomentella (2n = 38) displayed highly similar MAb 238 crossreactive isoelectric focusing banding patterns, indicating that they are genomically close to each other. Glycine hirticaulis was found to have both diploid (2n = 40) and tetraploid (2n = 80) cytotypes. We demonstrated that the MAb 238 was specific to the trypsin inhibitor domain of the BBI. The MAb 238 clearly reflected all the previously established relationships in the genus Glycine, validating its use as a genome marker. 相似文献
49.
Prakash C. Misra Theodore A. Craig Frederick L. Crane 《Journal of bioenergetics and biomembranes》1984,16(2):143-152
Carrot (Daucus carota L.) cells grown in suspension culture oxidized exogeneous NADH. The NADH oxidation was able to stimulate K+ (86Rb+) transport into cells, but it did not affect sucrose transport.N,N'-Dicyclohexyl-carbodiimide, diethylstilbestrol, and oligomycin, which only partially inhibited NADH oxidation, almost completely collapsed the K+ (86Rb+) transport. Vanadate, which is less effective as an ion transport inhibitor, was less effective in inhibiting the NADH-driven transport of K+ (86Rb+).p-Fluormethoxycarbonylcyanide phenylhydrazone inhibits the K+ transport over 90% including that induced by NADH. The results are interpreted as evidence that a plasma membrane redox system in root cells is closely associated with the ATPase which can drive K+ transport. Because of the inhibitor effects, it appears that membrane components common to the redox system and ATPase function in the transport of K+. 相似文献
50.
Iris B. Wilson Theodore E. Staley Linville J. Bush Stanley E. Gilliland 《Molecular and cellular biochemistry》1984,62(1):57-65
Summary Putative receptors for K88+ E. coli from piglet intestinal epithelium were released into the organ culture medium and were demonstrated by direct binding with K88+ E. coli through the utilization of an in vitro binding procedure or by immunoprecipitation with K88 antigen.Incorporation of 14C-glucosamine by newborn to day old and 3-week to 6-week old piglet jejunal and ileal mucosa, in organ culture, occurred throughout the 24 hr culture period. Uptake in both age groups and both areas of the intestine was similar with a somewhat greater incorporation by the older age group.Secretion of 14C-glucosamine-labeled components into the culture medium was demonstrated by gel filtration of the concentrated medium. Some large molecular weight components eluted in the void volume in excess of 2 x 106 daltons. A second peak of activity was spread from approximately 690K to 25K daltons. All eluted fractions demonstrated binding to K88+ E. coli.Antibodies to purified brush borders from susceptible pigs produced prominent precipitation bands following double diffusion with concentrated organ culture media which confirmed that the organ culture media contained labeled proteins of brush border origin.Immunoprecipitation of the intestinal mucosal organ culture media with K88+ pili and pilus antisera, followed by electrophoresis with SDS and reduced conditions, demonstrated a subunit of approximately 35K daltons. 相似文献