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621.
Human-induced processes are altering habitats at an unprecedented rate and scale. This has changed the biodiversity and biomass in many areas, but also led to phenotypic and genetic alterations of populations. Here we investigated the effects of the ongoing eutrophication in the Baltic Sea on the reproductive success of threespine stickleback males Gasterosteus aculeatus , through effects on reproductive behaviour and parenting ability. We allowed males to complete breeding cycles in a competitive setting under increased macro algae cover or increased turbidity caused by phytoplankton growth. Both environmental factors improved the parenting ability of the males and enhanced reproductive output. Increased alga growth and turbidity reduced aggressive interactions between males during the parental phase, probably due to reduced visibility, which slowed down a deterioration of condition. This increased the reproductive lifespan of the males and enabled them to complete more breeding cycles, as found when males were allowed to complete as many breeding cycles as they could under increased algae cover. In addition, increased turbidity improved oxygen conditions, which enhanced hatching success and reduced the need for vigorous fanning behaviour. Increased turbidity, however, relaxed selection on male size. Together with earlier results on relaxed sexual selection under changed environmental conditions, this suggests that the effect of eutrophication on stickleback populations is complex. It increases the reproductive output of populations, since more individuals are spawning within eutrophicated areas and their hatching success is increased, but it relaxes sexual and natural selection at the reproductive stage. Whether this will shift selection and population regulation to other life stages, such as the juvenile stage, deserves further investigations. 相似文献
622.
Tiina Nges 《International Review of Hydrobiology》1992,77(4):665-672
A comparison of two methods of zooplankton feeding experiments was performed in the Gulf of Finland. One was the advanced twin-bathometer method (in situ technique), the other — the “bottle method”. The main difference between the two methods is that it is not necessary to manipulate zooplankton to start an experiment in a twin bathometer, while manipulation is inevitable if the second method is used. In cases when the onset of the grazing experiment requires the manipulation of animals, the adaptation period lasts 2–4 hours and the optimal duration of experiment is 6–10 hours. If animals are not manipulated at the beginning of experiment, the adaptation period does not exist, the exposition time should not exceed 10 hours and the optimal duration of experiment is 2–4 hours. In long-term experiments (up to 24 hours) the fertilization effect of the excretion of concentrated zooplankton may cause underestimation of grazing rate. 相似文献
623.
Etvi Juntunen Riikka ArppeLaura Kalliomäki Teppo SalminenSheikh M. Talha Tiina MyyryläinenTero Soukka Kim Pettersson 《Analytical biochemistry》2016
Many quantitative and semiquantitative lateral flow (LF) assays have been introduced for clinical analytes such as biomarkers for cancer or acute myocardial infarction (AMI). Various detection technologies involving quantitative analyzing devices have been reported to have sufficient analytical sensitivity and quantification capability for clinical point-of-care tests. Fluorescence-based detection technologies such as quantum dots, Eu(III) nanoparticles, and photon-upconverting nanoparticles (UCNPs) have been introduced as promising solutions for point-of-care devices because of their high detectability by optical sensors. Lateral flow assays can be used for various sample types, e.g., urine, saliva, cerebrospinal fluid, and blood. This study focuses on the properties of serum and plasma because of their relevance in cancer and AMI diagnostics. The limit of detection was compared in LF assays having Eu(III) nanoparticles or UCNPs as reporters and the antibody configurations for two different analytes (prostate-specific antigen and cardiac troponin I (cTnI)). The results indicate a significant effect of anticoagulants in venipuncture tubes. The samples in K3EDTA tubes resulted in significant interference by decreased reporter particle mobility, and thus the limit of detection was up to eightfold less sensitive compared to serum samples. Despite the matrix interference in the cTnI assay with UCNP reporters, limits of detection of 41 ng/L with serum and 66 ng/L with the Li-heparin sample were obtained. 相似文献
624.
Cyclophosphamide-treated 18-day-old chick embryos were transplanted with cells from 7-day intraembryonic mesenchyme; the recipients and donors were identical at the major histocompatibility locus. At the age of 35 days, the cell recipients were studied to determine the reconstitution capacity of the transplanted cells. The transplantation resulted in a complete restoration of IgM and IgG class antibody production against human gammaglobulin and Brucella abortus, and of microscopic morphology of the bursa of Fabricius and of the germinal center formation in the spleen. These findings demonstrate that 7-day intraembryonic mesenchyme of the chick embryo harbor prebursal stem cells. These findings confirm our previous observations in the yolk sac-embryo chimeras indicating that lymphoid stem cells originate in the intraembryonic hematopoietic sites. 相似文献
625.
Tiina Ksenofontova 《Folia Geobotanica》1988,23(1):17-43
The present work was carried out at four waterbodies in the Estonian SSR where seven different habitats ofPhragmites australis were selected. The paper gives the results of the study of clones from essentially different sites: the characteristics of the habitat of the species (soil profile, soil analyses, pH of water), morphological features of shoots, the nutrient content in plant parts, the production of clones, and also relations between these characteristics. 相似文献
626.
Penelope Gray Hanna Kann Ville N. Pimenoff Tiina Eriksson Tapio Luostarinen Simopekka Vnsk Helj-Marja Surcel Helena Faust Joakim Dillner Matti Lehtinen 《PLoS medicine》2021,18(6)
BackgroundCervical cancer elimination through human papillomavirus (HPV) vaccination programs requires the attainment of herd effect. Due to its uniquely high basic reproduction number, the vaccination coverage required to achieve herd effect against HPV type 16 exceeds what is attainable in most populations. We have compared how gender-neutral and girls-only vaccination strategies create herd effect against HPV16 under moderate vaccination coverage achieved in a population-based, community-randomized trial.Methods and findingsIn 2007–2010, the 1992–1995 birth cohorts of 33 Finnish communities were randomized to receive gender-neutral HPV vaccination (Arm A), girls-only HPV vaccination (Arm B), or no HPV vaccination (Arm C) (11 communities per trial arm). HPV16/18/31/33/35/45 seroprevalence differences between the pre-vaccination era (2005–2010) and post-vaccination era (2011–2016) were compared between all 8,022 unvaccinated women <23 years old and resident in the 33 communities during 2005–2016 (2,657, 2,691, and 2,674 in Arms A, B, and C, respectively). Post- versus pre-vaccination-era HPV seroprevalence ratios (PRs) were compared by arm. Possible outcome misclassification was quantified via probabilistic bias analysis. An HPV16 and HPV18 seroprevalence reduction was observed post-vaccination in the gender-neutral vaccination arm in the entire study population (PR16 = 0.64, 95% CI 0.10–0.85; PR18 = 0.72, 95% CI 0.22–0.96) and for HPV16 also in the herpes simplex virus type 2 seropositive core group (PR16 = 0.64, 95% CI 0.50–0.81). Observed reductions in HPV31/33/35/45 seroprevalence (PR31/33/35/45 = 0.88, 95% CI 0.81–0.97) were replicated in Arm C (PR31/33/35/45 = 0.79, 95% CI 0.69–0.90).ConclusionsIn this study we only observed herd effect against HPV16/18 after gender-neutral vaccination with moderate vaccination coverage. With only moderate vaccination coverage, a gender-neutral vaccination strategy can facilitate the control of even HPV16. Our findings may have limited transportability to other vaccination coverage levels.Trial registrationClinicalTrials.gov number , https://clinicaltrials.gov/ct2/show/ NCT00534638. NCT00534638相似文献
627.
The sequence of hydrolytic reactions in the catabolism of theN-glycosidic oligosaccharide-to-protein region containing 6-linkedfucose on the asparagine-linked N-acetylglu-cosamine may varyfrom species to species. When 相似文献
628.
Tiina Myyryläinen Sheikh M Talha Sathyamangalam Swaminathan Raija Vainionpää Tero Soukka Navin Khanna Kim Pettersson 《Journal of nanobiotechnology》2010,8(1):27
A highly specific and novel dual-label time-resolved immunofluorometric assay was developed exploiting the unique emission
wavelengths of the intrinsically fluorescent terbium (Tb3+) and europium (Eu3+) tracers for the simultaneous detection of human immunodeficiency virus 1 (HIV-1) and hepatitis B virus (HBV) infections,
respectively. HIV-1 infection was detected using a double antigen sandwich format wherein anti-HIV-1 antibodies were captured
using an in vivo biotinylated version of a chimeric HIV-1 antigen and revealed using the same antigen labeled with Tb3+ chelate. Hepatitis B surface antigen (HBsAg), which served as the marker of HBV infection, was detected in a double antibody
sandwich using two monoclonal antibodies (mAbs), one chemically biotinylated to capture, and the other labeled with Eu3+ nanoparticles, to reveal. The performance of the assay was evaluated using a collection (n = 60) of in-house and commercially
available human sera panels. This evaluation showed the dual-label assay to possess high degrees of specificity and sensitivity,
comparable to those of commercially available, single analyte-specific kits for the detection of HBsAg antigen and anti-HIV
antibodies. This work demonstrates the feasibility of developing a potentially time- and resource-saving multiplex assay for
screening serum samples for multiple infections in a blood bank setting. 相似文献
629.
Laura Huilaja Tiina Hurskainen Helena Autio-Harmainen Silke C Hofmann Raija Sormunen Juha R?s?nen Mika Ilves Claus-Werner Franzke Leena Bruckner-Tuderman Kaisa Tasanen 《Matrix biology》2008,27(3):190-200
In pemphigoid gestationis (PG), autoantibodies target collagen XVII, a hemidesmosomal transmembrane protein, which is an important element in cutaneous epithelial adhesion and signalling. We report that collagen XVII is expressed in the first trimester and term syncytial and cytotrophoblastic cells of normal placenta and in epithelial cells of amniotic membrane. Immunoelectron microscopy confirmed the localization of collagen XVII to the hemidesmosomes of amniotic epithelium. Examination of three PG placentas showed mild villitis, but there were no differences between collagen XVII expression levels or immunostaining signals as compared to normal placenta. Collagen XVII expression was also detected in cultured extravillous trophoblast HTR-8/SVneo cells, where collagen XVII expression was upregulated by PMA and TGF-beta1. Interestingly, the presence of Col15, the cell migration domain of collagen XVII, induced the migration of HTR-8/SVneo cells in transmigration assay. Analysis of amniotic fluid samples at different gestational weeks revealed that a large quantity of collagen XVII ectodomain was shed into amniotic fluid throughout pregnancy. Biochemical and immunoblotting analysis indicated that the ectodomain in amniotic fluid is structurally very similar to the ectodomain produced by cultured keratinocytes. Cultured cells from amniotic fluid samples also expressed collagen XVII. Our results suggest that collagen XVII may contribute to the invasion of extravillous trophoblasts during placental development and is also required for the integrity of amniotic basement membrane. Although the exact pathomechanism of PG is still largely unknown, the clinical symptoms of PG are initiated after the expression of collagen XVII in placenta during the first trimester of pregnancy. 相似文献
630.