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111.
A karyotype of Ornithogalum chionophilum is presented. The relationship between this species and O. lanceolatum, O. cuspidatum and O. montanum is discussed. 相似文献
112.
Habitat fragmentation and the abandonment of former agricultural practices have led to extremely low dispersal rates for plant species growing in traditionally managed hay meadows in Sweden. Historically, seed dispersal between populations was maintained by hay movement, grazing animals, and farmers sharing their equipment. Because these means of dispersal typically are no longer occurring, artificial dispersal using seeds and plug-plants is tested here as a restoration tool. In this study, we chose two perennial herbs commonly occurring in meadows as test species, viz, Hypochoeris maculata L. (Asteraceae) and Succisa pratensis Moench. (Dipsacaceae). We found that plug-plant transplants were twice as effective as seed sowing for both species. The seed collection site was found to be important for seed-based establishment and survival; consequently, the choice of donor meadow is important when acquiring seeds used for restoration. We also found that survival of plants introduced as seeds was generally lower at sites harboring species favored by nitrogen as well as at sites in later successional phases. Both methods of introducing meadow species worked well, even though long-term establishment may well be more successful with the plug-plant method due to higher plug-plant establishment 2 years after introduction in the field. 相似文献
113.
Ann-Kristin Eriksson Wiklund Brita Sundelin 《Journal of experimental marine biology and ecology》2008,367(2):81-90
In the present study, we investigate the effects of food quality (with three distinct algal diets) and quantity (high vs. low carbon and nitrogen contents) and competition (with natural polychaete competitor, Marenzelleria spp) on the semelparous amphipod Monoporeia affinis fitness and reproduction. Contrary to other studies on this species, our results showed that amphipod females have the ability to adjust their offspring investment when conditions were significantly altered before mating in terms of food quantity, while food quality was of less importance. In fact, there was only a low beneficial effect on amphipod reproduction and embryonic development of a presumed high quality diatom diet. Also, the presence of a natural competitor did not affect amphipod reproductive outcome. The results are viewed in the context of a dramatic decline observed on the amphipod populations in the Gulf of Bothnia. Though, several plausible hypotheses have been suggested for the decline, including competition, new anthropogenic substances, hypoxia and predation, we hypothesize that the population decline is related to food shortage and malnutrition due to an increased percentage low quality terrestrial carbon (rich in humus) from river outflow into the Gulf of Bothnia. Concomitantly, the bacterial food web was enhanced, which has a lower trophic efficiency. We also suggest that a secondary effect of malnutrition is an increased susceptibility to other types of stressors such as contaminants and parasites. 相似文献
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116.
Effective Recovery of Bacterial DNA and Percent-Guanine-Plus-Cytosine-Based Analysis of Community Structure in the Gastrointestinal Tract of Broiler Chickens 总被引:2,自引:4,他引:2 下载免费PDF全文
Juha H. A. Apajalahti Laura K. Srkilahti Brita R. E. Mki J. Pekka Heikkinen Pivi H. Nurminen William E. Holben 《Applied microbiology》1998,64(10):4084-4088
A DNA-based, direct method for initial characterization of the total bacterial community in ileum and cecum of the chicken gastrointestinal (GI) tract was developed. The efficiencies of bacterial extraction and lysis were >95 and >99%, respectively, and therefore the DNA recovered should accurately reflect the bacterial communities of the ileal and cecal digesta. Total bacterial DNA samples were fractionated according to their percent G+C content. The profiles reflecting the composition of the bacterial community were reproducible within each compartment, but different between the compartments of the GI tract. This approach is independent of the culturability of the bacteria in the consortium and can be used to improve our understanding of how diet and other variables modulate the microbial communities of the GI tracts of animals. 相似文献
117.
The purpose of this study was to evaluate a consecutive series of patients operated on with prophylactic mastectomy and immediate breast reconstruction with implants, focusing on preoperative assessment, technical aspects of surgical outcome, and number of postoperative complications on a short-term basis. Thirty consecutive healthy women with an increased risk of breast cancer who were therefore operated on with bilateral prophylactic mastectomy and immediate breast reconstruction are reported. A multidisciplinary approach with a geneticist, general surgeon, plastic surgeon, specially trained nurse, psychologist, gynecologist, and oncologist was used preoperatively, with thorough information provided to the patient about the surgery. Eleven patients had gene mutations, and in all patients, the geneticist had performed a risk assessment. The mean age of the patients was 41 years. The technique was modified over time with smaller or special incisions and tailor-made adjustments for each patient. Great care was taken to remove all breast tissue. The tops of the breast nipples were regrafted for cosmetic purposes, and the base was sent for histopathologic examination. In most cases, permanent expander prostheses with detachable valves were used. The areolas were tattooed, if they were not left in place. No patient had occult cancer or carcinoma in situ. Four postoperative complications occurred, including two hematomas, one infection (treated with antibiotics), and one pneumothorax in a patient with severe asthma. All reconstructions were fulfilled. The mean hospital stay was 5.7 days. The time from mastectomy to the final tattooing of the areolas was 260 days. All patients returned to normal daily activities after fulfilled reconstruction. 相似文献
118.
Perez-Martinez P Delgado-Lista J Garcia-Rios A Mc Monagle J Gulseth HL Ordovas JM Shaw DI Karlström B Kiec-Wilk B Blaak EE Helal O Malczewska-Malec M Defoort C Risérus U Saris WH Lovegrove JA Drevon CA Roche HM Lopez-Miranda J 《PloS one》2011,6(6):e20555
Glucokinase Regulatory Protein (GCKR) plays a central role regulating both hepatic triglyceride and glucose metabolism. Fatty acids are key metabolic regulators, which interact with genetic factors and influence glucose metabolism and other metabolic traits. Omega-3 polyunsaturated fatty acids (n-3 PUFA) have been of considerable interest, due to their potential to reduce metabolic syndrome (MetS) risk.
Objective
To examine whether genetic variability at the GCKR gene locus was associated with the degree of insulin resistance, plasma concentrations of C-reactive protein (CRP) and n-3 PUFA in MetS subjects.Design
Homeostasis model assessment of insulin resistance (HOMA-IR), HOMA-B, plasma concentrations of C-peptide, CRP, fatty acid composition and the GCKR rs1260326-P446L polymorphism, were determined in a cross-sectional analysis of 379 subjects with MetS participating in the LIPGENE dietary cohort.Results
Among subjects with n-3 PUFA levels below the population median, carriers of the common C/C genotype had higher plasma concentrations of fasting insulin (P = 0.019), C-peptide (P = 0.004), HOMA-IR (P = 0.008) and CRP (P = 0.032) as compared with subjects carrying the minor T-allele (Leu446). In contrast, homozygous C/C carriers with n-3 PUFA levels above the median showed lower plasma concentrations of fasting insulin, peptide C, HOMA-IR and CRP, as compared with individuals with the T-allele.Conclusions
We have demonstrated a significant interaction between the GCKR rs1260326-P446L polymorphism and plasma n-3 PUFA levels modulating insulin resistance and inflammatory markers in MetS subjects. Further studies are needed to confirm this gene-diet interaction in the general population and whether targeted dietary recommendations can prevent MetS in genetically susceptible individuals.Trial Registration
ClinicalTrials.gov NCT00429195相似文献119.
Recombinant Sendai virus expressing the G glycoprotein of respiratory syncytial virus (RSV) elicits immune protection against RSV 总被引:4,自引:0,他引:4 下载免费PDF全文
Takimoto T Hurwitz JL Coleclough C Prouser C Krishnamurthy S Zhan X Boyd K Scroggs RA Brown B Nagai Y Portner A Slobod KS 《Journal of virology》2004,78(11):6043-6047
Although RSV causes serious pediatric respiratory disease, an effective vaccine does not exist. To capture the strengths of a live virus vaccine, we have used the murine parainfluenza virus type 1 (Sendai virus [SV]) as a xenogeneic vector to deliver the G glycoprotein of RSV. It was previously shown (J. L. Hurwitz, K. F. Soike, M. Y. Sangster, A. Portner, R. E. Sealy, D. H. Dawson, and C. Coleclough, Vaccine 15:533-540, 1997) that intranasal SV protected African green monkeys from challenge with the related human parainfluenza virus type 1 (hPIV1), and SV has advanced to clinical trials as a vaccine for hPIV1 (K. S. Slobod, J. L. Shenep, J. Lujan-Zilbermann, K. Allison, B. Brown, R. A. Scroggs, A. Portner, C. Coleclough, and J. L. Hurwitz, Vaccine, in press). Recombinant SV expressing RSV G glycoprotein was prepared by using reverse genetics, and intranasal inoculation of cotton rats elicited RSV-specific antibody and elicited protection from RSV challenge. RSV G-recombinant SV is thus a promising live virus vaccine candidate for RSV. 相似文献
120.
Brita Stedje 《Nordic Journal of Botany》1994,14(1):43-44
Drímia exigua , a small and slender species, is described from the Guder river valley in Ethiopia. 相似文献