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排序方式: 共有343条查询结果,搜索用时 15 毫秒
71.
ABSTRACT The term bodyscape encourages thinking about representation of bodies at multiple scales—from different bodies as they move through space to the microlandscape of individual bodily differences. A hegemonic bodyscape's representations tend to idealize and essentialize bodies' differences to reinforce normative ideas about a society's socioeconomic organization. But, a dominant bodyscape is never absolute. Bodyscapes that depart from or subvert hegemonic representations may simultaneously exist. In Western society, the biomedical bodyscape predominates in scientific understandings of bodily difference. Its representation of sex differences conveys heteronormative notions about gender and sexuality. Because the biomedical bodyscape frames studies of ancient bodies, investigators need recognize how their considerations of labor divisions, familial organization, and reproduction may situate modern (hetero)sexist representations deep within antiquity. To innovate analyses of socioeconomic relations, queer theory allows scholars to interrogate human nature. Doing so produces alternative bodyscapes that represent the diversity of past peoples' social and sexual lives. [Keywords: bodyscape, heteronormativity, queer theory, bioarchaeology, paleoanthropology] 相似文献
72.
Molés G Zanuy S Muñoz I Crespo B Martínez I Mañanós E Gómez A 《Biology of reproduction》2011,84(6):1171-1181
Different yields, biopotency, and in vivo pharmacokinetics are obtained for recombinant sea bass gonadoltropins depending on the production system and DNA construct, but they show specific activation of their corresponding receptors. Gonadotropins (GTHs) are glycoprotein hormones that play a major role in the regulation of gonadal functions. Recently, we succeeded in isolating the native sea bass Fsh from sea bass pituitaries, but to ensure the availability of bioactive GTHs and no cross-contamination with other related glycoproteins, recombinant sea bass GTHs were produced using two expression systems-insect and mammalian cells-and different constructs that yielded tethered or noncovalently bound dimers. Their production levels, binding specificity to their homologous cognate receptors, and bioactivity were investigated and compared. Both expression systems were successful in the generation of bioactive recombinant GTHs, but insect Sf9 cells yielded higher amounts of recombinant proteins than mammalian Chinese Hamster Ovary (CHO) stable clones. All recombinant GTHs activated their cognate receptors without cross-ligand binding and were able to stimulate sea bass gonadal steroidogenesis in vitro, although with different biopotencies. To assess their use for in vivo applications, their half-life in sea bass plasma was evaluated. Sf9-GTHs had a lower in vivo stability compared with CHO-GTHs due to their rapid clearance from the blood circulation. Cell-dependent glycosylation could be contributing to the final in vivo stability and biopotency of these recombinant glycoproteins. In conclusion, both insect and mammalian expression systems produced bioactive sea bass recombinant gonadotropins, although with particular features useful for different proposes (e.g., antibody production or in vivo studies, respectively). 相似文献
73.
Lowe I Jankuloski L Chao S Chen X See D Dubcovsky J 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2011,123(1):143-157
A mapping population of 186 recombinant inbred lines developed from a cross between UC1110, an adapted California spring wheat,
and PI610750, a synthetic derivative from CIMMYT’s Wide Cross Program, was evaluated for its response to current California
races of stripe rust (Puccinia striiformis f. sp. tritici) in replicated field trials over four seasons (2007–2010) in the northern Sacramento Valley. A genetic map was constructed
consisting of 1,494 polymorphic probes (SSRs, DArTs, and ESTs) mapped to 558 unique loci, and QTL analysis revealed the presence
of four stripe rust resistance QTL segregating in this population, two from UC1110 (on chromosomes 3BS and 2BS) and two from
PI610750 (5AL and 2AS). The two QTL of largest effects (on 3BS and 5AL) were validated in independent populations and their
intervals narrowed to 2.5 and 5.3 cM, respectively. The 3BS QTL was shown, by allelism test and genotype, to carry a gene
different from the Yr30/Sr2 complex. Mapped position also suggests that the 3BS QTL is associated with a gene different from either Yrns-B1 or YrRub, two stripe rust resistance genes mapped to this region in other studies. The 5AL QTL carries a previously unreported partial
stripe rust resistance gene, designated here as Yr48. This paper discusses the individual contributions to resistance of these four QTL, their epistatic interactions, and their
potential in durable resistance breeding strategies based on combinations of partial resistance genes. 相似文献
74.
Reduced genetic diversity due to founder effects often is expected for invasive populations. The present study examined two nuclear gene regions and one mitochondrial gene to evaluate the origins and genetic diversity of Gemma gemma, a ‘stow-away’ that was introduced to California more than 100 years ago with the importation of the Eastern oyster, Crassostrea virginica, from the United States’ Atlantic coast. A previous investigation involving mitochondrial DNA cytochrome-c-oxidase subunit I sequences reported no significant difference in haplotype diversity between the native and introduced populations; however, estimates of allelic (or haplotypic) variability are insensitive to losses of rare alleles that may accompany founder events and population bottlenecks. Estimates of allele richness and the distribution of rare alleles provide more sensitive indicators of such events. The present investigation of introduced and potential source populations identified lower allele richness and number of singleton alleles in California samples. Atlantic coast Gemma exhibit a sharp phylogeographic transition between northeastern (New York through New England) and mid-Atlantic (southern New Jersey through Virginia) subpopulations, which appear latitudinally inverted for the California Gemma populations. These genetic results, and information from the transportation history of the Eastern oyster, help to clarify processes involved in the introduction of this invasive species. 相似文献
75.
Judy M. Bradley Paul Koker Qiqi Deng Petra Moroni-Zentgraf Felix Ratjen David E. Geller J. Stuart Elborn 《PloS one》2014,9(9)
Background
Tiotropium is a once-daily, long-acting anticholinergic bronchodilator with the potential to alleviate airway obstruction in cystic fibrosis. Our objective was to evaluate the efficacy and safety of 2.5 and 5 µg once-daily tiotropium delivered via the Respimat Soft Mist Inhaler vs. placebo in people with cystic fibrosis.Methods
This phase 2, 12-week, randomized, double-blind, placebo-controlled parallel-group study of tiotropium Respimat as add-on to usual cystic fibrosis maintenance therapy included people with cystic fibrosis with pre-bronchodilator forced expiratory volume in 1 second (FEV1) ≥25% predicted. Co-primary efficacy end points were change from baseline in percent-predicted FEV1 area under the curve from 0 to 4 hours (FEV1 AUC0–4h), and trough FEV1 at the end of week 12.Findings
A total of 510 subjects with cystic fibrosis aged 5–69 years were randomized. Both doses of tiotropium resulted in significant improvement compared with placebo in the co-primary efficacy end points at the end of week 12 (change from baseline in percent-predicted FEV1 AUC0–4h: 2.5 µg: 2.94%, 95% confidence interval 1.19–4.70, p = 0.001; 5 µg: 3.39%, 95% confidence interval 1.67–5.12, p = 0.0001; in percent-predicted trough FEV1∶2.5 µg: 2.24%, p = 0.2; 5 µg: 2.22%, p = 0.02). There was a greater benefit with tiotropium 5 vs. 2.5 µg. No treatment-related adverse events or unexpected safety findings were observed in patients taking tiotropium.Conclusions
Tiotropium significantly improved lung function in people with cystic fibrosis. The improvement was greater with the higher dose than the lower dose, with no difference in adverse events.Trial Registration
ClinicalTrials.gov NCT00737100EudraCT 2008-001156-43. 相似文献76.
Anthropogenic vectors have moved marine species around the world leading to increased invasions and expanded species'' ranges. The biotic resistance hypothesis of Elton (in The ecology of invasions by animals and plants, 1958) predicts that more diverse communities should have greater resistance to invasions, but experiments have been equivocal. We hypothesized that species richness interacts with other factors to determine experimental outcomes. We manipulated species richness, species composition (native and introduced) and availability of bare space in invertebrate assemblages in a marina in Monterey, CA. Increased species richness significantly interacted with both initial cover of native species and of all organisms to collectively decrease recruitment. Although native species decreased recruitment, introduced species had a similar effect, and we concluded that biotic resistance is conferred by total species richness. We suggest that contradictory conclusions in previous studies about the role of diversity in regulating invasions reflect uncontrolled variables in those experiments that modified the effect of species richness. Our results suggest that patches of low diversity and abundance may facilitate invasions, and that such patches, once colonized by non-indigenous species, can resist both native and non-indigenous species recruitment. 相似文献
77.
Chromium has been implicated as a cofactor in the maintenance of normal lipid and carbohydrate metabolism. A deficiency of chromium results from diets low in biologically available chromium. Picolinic acid, a metabolite of tryptophan, forms stable complexes with transitional metal ions, which results in an improved bioavailability of the metal ion chromium. To determine whether or not chromium picolinate is effective in humans, 28 volunteer subjects were given either chromium tripicolinate (3.8 micromol [200 micrograms] chromium) or a placebo daily for 42 days in a double-blind crossover study. A 14-day period off capsules was used between treatments. Levels of total cholesterol, low-density lipoprotein (LDL) cholesterol, and apolipoprotein B, the principal protein of the LDL fraction, decreased significantly while the subjects were ingesting chromium picolinate. The concentration of apolipoprotein A-I, the principal protein of the high-density lipoprotein (HDL) fraction, increased substantially during treatment with chromium picolinate. The HDL-cholesterol level was elevated slightly but not significantly during ingestion of chromium picolinate. Only apolipoprotein B, of the variables measured, was altered significantly during supplementation with the placebo. These observations show that chromium picolinate is efficacious in lowering blood lipids in humans. 相似文献
78.
Dry weights of individual Daphnia galeata and D. hyalina, whichcoexist in Lake Constance, were determined weekly during a twoyear investigation. From each sample and each species a lengthweightrelationship (LWR) was calculated resulting in 54 (65) regressionequations based on N=2466 (3032) in D. galeata (D. hyalina).The constants (Ln(A)) and (B) of the LWRs showed a marked seasonalvariability, ranging from Ln(A)=1.07842.4740(1.01522.3860)and B=2.144.20 (2.114.15). The seasonal variabilityof the LWR was estimated with four different models. Condensingthe 54 (65) equations into one seasonal cycle resulted in amodel with an explained variance of r2=0.873 (0.869). Threemore models were established by calculating multiple regressionswith take stratification, average fecundity (E), and food concentrationas determining variates. Differences in LWRs of the two Daphniaspecies were significant (p <0.001). As the most useful approximationduring the period of stratification, LWRs are recommended forD. galeata: Ln(W)=(1.5674+0.0287*(E))+Ln(L)*(3.3611+0.0111*(E)) as a generalized LWR for an epilimnetic daphnid, and for D.hyalina: Ln(W)=(1.5593+0.0613*(E))+Ln(L)*(3.2709+0.0017*(E)) as LWR for a daphnid which migrates diurnally between epi andhypolimnion. The explained variance of this model is r2=0.843(0.826). The influence of food concentration in the epilimnionon LWRs was found to be significant on Ln(A) but not on (B).
*This research project was supported by the Deutsche Forschungsgemeinschaft 相似文献
79.
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