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171.
Nucleotide polymorphisms at genomic regions including 17 nuclear loci, two chloroplast and one mitochondrial DNA fragments were used to study the speciation history of three pine species: dwarf mountain pine (Pinus mugo), peat‐bog pine (P. uliginosa) and Scots pine (P. sylvestris). We set out to investigate three specific speciation scenarios: (I) P. uliginosa is a homoploid hybrid between the other two, (II) the species have evolved without gene flow after divergence and (III) there has been substantial gene flow between the species since their divergence. Overall, the genetic data suggest that P. mugo and P. uliginosa share the same gene pool (average net divergence of 0.0001) and that the phenotypic differences (e.g. growth form) are most likely due to very limited areas of the genome. P. mugo and P. uliginosa are more diverged from P. sylvestris than from each other (average net divergence of 0.0027 and 0.0026, respectively). The nucleotide patterns can best be explained by the divergence with migration speciation scenario, although the hybrid speciation scenario with small genomic contribution from P. sylvestris cannot be completely ruled out. We suggest that the large amount of shared polymorphisms between the pine taxa and the lack of monophyly at all loci studied between P. sylvestris and P. mugo–P. uliginosa can largely be explained by relatively recent speciation history and large effective population sizes but also by interspecific gene flow. These closely related pine taxa form an excellent system for searching for loci involved in adaptive variation as they are differentiated in phenotype and ecology but have very similar genetic background. 相似文献
172.
Inbreeding reveals mode of past selection on male reproductive characters in Drosophila melanogaster
Outi Ala‐Honkola David J. Hosken Mollie K. Manier Stefan Lüpold Elizabeth M. Droge‐Young Kirstin S. Berben William F. Collins John M. Belote Scott Pitnick 《Ecology and evolution》2013,3(7):2089-2102
Directional dominance is a prerequisite of inbreeding depression. Directionality arises when selection drives alleles that increase fitness to fixation and eliminates dominant deleterious alleles, while deleterious recessives are hidden from it and maintained at low frequencies. Traits under directional selection (i.e., fitness traits) are expected to show directional dominance and therefore an increased susceptibility to inbreeding depression. In contrast, traits under stabilizing selection or weakly linked to fitness are predicted to exhibit little‐to‐no inbreeding depression. Here, we quantify the extent of inbreeding depression in a range of male reproductive characters and then infer the mode of past selection on them. The use of transgenic populations of Drosophila melanogaster with red or green fluorescent‐tagged sperm heads permitted in vivo discrimination of sperm from competing males and quantification of characteristics of ejaculate composition, performance, and fate. We found that male attractiveness (mating latency) and competitive fertilization success (P2) both show some inbreeding depression, suggesting they may have been under directional selection, whereas sperm length showed no inbreeding depression suggesting a history of stabilizing selection. However, despite having measured several sperm quality and quantity traits, our data did not allow us to discern the mechanism underlying the lowered competitive fertilization success of inbred (f = 0.50) males. 相似文献
173.
Katri Krkkinen Helmi Kuittinen Rob van Treuren Claus Vogl Sami Oikarinen Outi Savolainen 《Evolution; international journal of organic evolution》1999,53(5):1354-1365
Inbreeding depression may be caused by (partially) recessive or overdominant gene action. The relative evolutionary importance of these two modes has been debated; the former mode is emphasized in the “dominance hypothesis,” the latter in the “overdominance hypothesis.” We analyzed the genetic basis of inbreeding depression in the self-incompatible herb Arabis petraea (L.) Lam.: In the selfed progeny of twelve parental plants, we studied the proportion of chlorophyll-deficient seedlings, the genotypic distributions of marker genes, and associations of marker genotypes with viability and quantitative traits. Early components of fitness were examined by scoring seed size, germination time, and early growth rate and by observing the proportion of chlorophyll-deficient seedlings. Later components of fitness, flowering, and root and aboveground biomass were also measured. Marker genotypes of young seedlings were scored for 11 enzyme loci and three microsatellite markers. We found a high proportion (about 70%) of families with chlorophyll-deficient seedlings, indicating a high mutational load. We found six significant deviations from 1:2:1 ratio at marker loci of 60 tests in seedlings, with three of these significant at the experimentwide level. Deviations from the expected ratio were assumed to be due to linked viability loci. A graphical and a Bayesian method were used to distinguish between the overdominance and dominance hypotheses. Most of the deviant segregation ratios suggested overdominance instead of recessivity of the deleterious allele. Neither the early (seed size, germination time, or early growth trait) nor the late quantitative traits (flowering, and root and aboveground biomass) showed significant linkage to markers at the experimentwide level. Presence of significant associations between markers and early viability, but lack thereof for quantitative traits expressed late, suggests either that there may be relatively low inbreeding depression in later life stages or that individual quantitative trait loci may have smaller effects than loci contributing to early viability. 相似文献
174.
Minna Pekkinen Elisa Saarnio Heli T. Viljakainen Elina Kokkonen Jette Jakobsen Kevin Cashman Outi M?kitie Christel Lamberg-Allardt 《PloS one》2014,9(1)
Vitamin D binding protein (DBP)/group-specific component (Gc), correlates positively with serum vitamin D metabolites, and phenotype influences serum 25-hydroxyvitamin D (S-25(OH)D) concentration. The protein isoform has been associated with decreased bone mineral density (BMD) and increased fracture risk. We examined the role of GC genotypes in S-25(OH)D status and BMD in 231 Finnish children and adolescents aged 7−19 yr. BMD was measured with DXA from lumbar spine (LS), total hip, and whole body, and for 175 subjects, radial volumetric BMD was measured with pQCT. Background characteristic and total dietary intakes of vitamin D and calcium were collected. The concentrations of 25(OH)D, parathyroid hormone (PTH), calcium and other markers of calcium homeostasis were determined from blood and urine. Genotyping was based on single-nucleotide polymorphism (rs4588) in the GC gene. The genotype distribution was: GC 1/1 68%, GC 1/2 26% and GC 2/2 6%. A significant difference emerged in 25(OH)D and PTH concentrations between the genotypes, (p = 0.001 and 0.028 respectively, ANCOVA). There was also a linear trend in: Gc 2/2 had the lowest 25(OH)D and PTH concentrations (p = 0.025 and 0.012, respectively). Total hip bone mineral content was associated with GC genotype (BMC) (p = 0.05, ANCOVA) in boys. In regression analysis, after adjusting for relevant covariates, GC genotype was associated with LS BMC and strength and strain index (SSI) Z-score in both genders, and LS BMD in boys. In conclusion, the present study demonstrates the association between GC genotypes and S-25(OH)D and PTH concentrations. The results show the influence of DBP genetic variation on bone mass accrual in adolescence. 相似文献
175.
Katri Jalava Hanna Rintala Jukka Ollgren Leena Maunula Vicente Gomez-Alvarez Joana Revez Marja Palander Jenni Antikainen Ari Kauppinen Pia R?s?nen Sallamaari Siponen Outi Nyholm Aino Kyyhkynen Sirpa Hakkarainen Juhani Merentie Martti P?rn?nen Raisa Loginov Hodon Ryu Markku Kuusi Anja Siitonen Ilkka Miettinen Jorge W. Santo Domingo Marja-Liisa H?nninen Tarja Pitk?nen 《PloS one》2014,9(8)
Failures in the drinking water distribution system cause gastrointestinal outbreaks with multiple pathogens. A water distribution pipe breakage caused a community-wide waterborne outbreak in Vuorela, Finland, July 2012. We investigated this outbreak with advanced epidemiological and microbiological methods. A total of 473/2931 inhabitants (16%) responded to a web-based questionnaire. Water and patient samples were subjected to analysis of multiple microbial targets, molecular typing and microbial community analysis. Spatial analysis on the water distribution network was done and we applied a spatial logistic regression model. The course of the illness was mild. Drinking untreated tap water from the defined outbreak area was significantly associated with illness (RR 5.6, 95% CI 1.9–16.4) increasing in a dose response manner. The closer a person lived to the water distribution breakage point, the higher the risk of becoming ill. Sapovirus, enterovirus, single Campylobacter jejuni and EHEC O157:H7 findings as well as virulence genes for EPEC, EAEC and EHEC pathogroups were detected by molecular or culture methods from the faecal samples of the patients. EPEC, EAEC and EHEC virulence genes and faecal indicator bacteria were also detected in water samples. Microbial community sequencing of contaminated tap water revealed abundance of Arcobacter species. The polyphasic approach improved the understanding of the source of the infections, and aided to define the extent and magnitude of this outbreak. 相似文献
176.
Anu?K?LappalainenEmail author Elina?Vaittinen Jouni?Junnila Outi?Laitinen-Vapaavuori 《Acta veterinaria Scandinavica》2014,56(1):89
Background
Intervertebral disc disease (IDD) is a very common neurological disease, Dachshunds being the breed most often affected. In this breed, IDD has a hereditary background and is associated with intervertebral disc calcification (IDC), an indicator of severe intervertebral disc degeneration. In Finland, spinal radiography is used, when screening for IDC before breeding Dachshunds. We evaluated the association between IDC and IDD in Finnish Dachshunds radiographically screened for IDC.A questionnaire was sent to owners of 193 radiographically screened Dachshunds aged at least ten years. Clinical signs indicative of IDD were compared with IDC grade (grade 0?=?no calcifications, grade 1?=?1 – 2 calcifications, grade 2?=?3 – 4 calcifications and grade 3?=?5 or more calcifications) and with age at the time of the radiographic examination. The diagnosis of IDD was confirmed by a veterinarian.Results
IDD was common in the study population with 31% of dogs being affected. IDD and IDC were clearly connected (P?<?0.001); IDD was rare in dogs with no calcifications (grade 0) and common in dogs with severe IDC (grade 3). The IDC grade was strongly positively associated with frequency of back pain periods (P?<?0.001), and dogs with IDC grade 3 had frequent periods of pain. Reluctance to jump onto a sofa had a strong positive association with back pain. No association existed between age of the dog at the time of the radiographic examination and clinical signs indicative of IDD.Conclusions
Radiographically detected IDC and IDD are common in Finnish Dachshunds and are strongly associated with one another. Spinal radiography is an appropriate screening tool for breeders attempting to diminish IDC and IDD in Dachshunds. A breeding program that screens dogs and selects against IDC can be expected to reduce the occurrence of IDD in future. Twenty-four to 48 months of age is a suitable age for screening.177.
Allozyme variation has been and continues to be a major source of information on the level of genetic variation among plant
species. Deciphering the molecular basis of electrophoretic variation is essential for understanding the forces affecting
the protein level variation. In this study, the relationship between allozyme heterozygosity and nucleotide diversity in plants
is investigated among and within species. Allozyme and nucleotide diversity in 27 plant species was reviewed. At the multilocus
level, the two methods are congruent: a clear correlation between the two measures of genetic diversity among plant species
was observed, strengthening the view that effective population size is the major determinant of genome-wide diversity. Nucleotide
diversity at six allozyme coding genes (6pgdB, aco, gdh, gotC, mdhA, and mdhB) in conifer Pinus sylvestris was investigated jointly with electrophoretic data. Single non-synonymous charge-changing mutations were found together with
electrophoretic alleles that consequently were mutationally unique. Synonymous site nucleotide diversity (point estimate of
θ
W—0.009 per bp) and silent site divergence from Pinus pinaster at allozyme coding loci were at comparable levels with other loci in the species. Linkage disequilibrium was extensive compared
to earlier estimates from P. sylvestris and other trees, spanning several kilobases. Allozyme coding genes had an excess of closely related haplotypes whose frequency
has recently increased possibly as a result of partial selective sweeps or balancing selection, but complex demographic effects
cannot be excluded. 相似文献
178.
Turunen SP Kummu O Harila K Veneskoski M Soliymani R Baumann M Pussinen PJ Hörkkö S 《PloS one》2012,7(4):e34910
Objective
Increased risk for atherosclerosis is associated with infectious diseases including periodontitis. Natural IgM antibodies recognize pathogen-associated molecular patterns on bacteria, and oxidized lipid and protein epitopes on low-density lipoprotein (LDL) and apoptotic cells. We aimed to identify epitopes on periodontal pathogen Porphyromonas gingivalis recognized by natural IgM binding to malondialdehyde (MDA) modified LDL.Methods and Results
Mouse monoclonal IgM (MDmAb) specific for MDA-LDL recognized epitopes on P. gingivalis on flow cytometry and chemiluminescence immunoassays. Immunization of C57BL/6 mice with P. gingivalis induced IgM, but not IgG, immune response to MDA-LDL and apoptotic cells. Immunization of LDLR−/− mice with P. gingivalis induced IgM, but not IgG, immune response to MDA-LDL and diminished aortic lipid deposition. On Western blot MDmAb bound to P. gingivalis fragments identified as arginine-specific gingipain (Rgp) by mass spectrometry. Recombinant domains of Rgp produced in E. coli were devoid of phosphocholine epitopes but contained epitopes recognized by MDmAb and human serum IgM. Serum IgM levels to P. gingivalis were associated with anti-MDA-LDL levels in humans.Conclusion
Gingipain of P. gingivalis is recognized by natural IgM and shares molecular identity with epitopes on MDA-LDL. These findings suggest a role for natural antibodies in the pathogenesis of two related inflammatory diseases, atherosclerosis and periodontitis. 相似文献179.
Nohynek H Jokinen J Partinen M Vaarala O Kirjavainen T Sundman J Himanen SL Hublin C Julkunen I Olsén P Saarenpää-Heikkilä O Kilpi T 《PloS one》2012,7(3):e33536
Background
Narcolepsy is a chronic sleep disorder with strong genetic predisposition causing excessive daytime sleepiness and cataplexy. A sudden increase in childhood narcolepsy was observed in Finland soon after pandemic influenza epidemic and vaccination with ASO3-adjuvanted Pandemrix. No increase was observed in other age groups.Methods
Retrospective cohort study. From January 1, 2009 to December 31, 2010 we retrospectively followed the cohort of all children living in Finland and born from January 1991 through December 2005. Vaccination data of the whole population was obtained from primary health care databases. All new cases with assigned ICD-10 code of narcolepsy were identified and the medical records reviewed by two experts to classify the diagnosis of narcolepsy according to the Brighton collaboration criteria. Onset of narcolepsy was defined as the first documented contact to health care because of excessive daytime sleepiness. The primary follow-up period was restricted to August 15, 2010, the day before media attention on post-vaccination narcolepsy started.Findings
Vaccination coverage in the cohort was 75%. Of the 67 confirmed cases of narcolepsy, 46 vaccinated and 7 unvaccinated were included in the primary analysis. The incidence of narcolepsy was 9.0 in the vaccinated as compared to 0.7/100,000 person years in the unvaccinated individuals, the rate ratio being 12.7 (95% confidence interval 6.1–30.8). The vaccine-attributable risk of developing narcolepsy was 1∶16,000 vaccinated 4 to 19-year-olds (95% confidence interval 1∶13,000–1∶21,000).Conclusions
Pandemrix vaccine contributed to the onset of narcolepsy among those 4 to 19 years old during the pandemic influenza in 2009–2010 in Finland. Further studies are needed to determine whether this observation exists in other populations and to elucidate potential underlying immunological mechanism. The role of the adjuvant in particular warrants further research before drawing conclusions about the use of adjuvanted pandemic vaccines in the future. 相似文献180.
Partinen M Saarenpää-Heikkilä O Ilveskoski I Hublin C Linna M Olsén P Nokelainen P Alén R Wallden T Espo M Rusanen H Olme J Sätilä H Arikka H Kaipainen P Julkunen I Kirjavainen T 《PloS one》2012,7(3):e33723