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61.
Overall, mammalian herbivores are more harmful in mixed plantations than in monocultures, but the effect of herbivore abundance has not been experimentally tested in this context. It has been proposed that there is a critical threshold density where herbivore pressure spreads from preferred plants to everything edible, leading to non-linear density effects on low-quality plants. We experimentally investigated whether survival of an unpalatable plant is similarly related to herbivore density in both monocultures and mixed stands. This we did by establishing monocultures of unpalatable black alder (Alnus glutinosa) and mixed stands of black alder and five more palatable tree species in enclosures, where Microtus voles were introduced and their abundances monitored.The effect of stand diversity tended to depend on vole abundance. Vole damage of tree saplings did not differ between monocultures and mixed stands, but at higher vole abundances attacks had a stronger effect on sapling survival in the monocultures. Sapling survival showed a significant drop in the monocultures at peak abundance of approximately 300 voles ha?1. In monocultures herbivores do not have alternatives and therefore are forced to become deadlier consumers. 相似文献
62.
Kamiya Chiaki Odagiri Keiichi Hakamata Akio Sakurada Ryugo Inui Naoki Watanabe Hiroshi 《Molecular biology reports》2021,48(7):5503-5511
Molecular Biology Reports - Although high doses of proton pump inhibitors can elicit an anticancer effect, this strategy may impair vascular biology. In particular, their effects on endothelial... 相似文献
63.
Lahti L Elo LL Aittokallio T Kaski S 《IEEE/ACM transactions on computational biology and bioinformatics / IEEE, ACM》2011,8(1):217-225
Probe defects are a major source of noise in gene expression studies. While existing approaches detect noisy probes based on external information such as genomic alignments, we introduce and validate a targeted probabilistic method for analyzing probe reliability directly from expression data and independently of the noise source. This provides insights into the various sources of probe-level noise and gives tools to guide probe design. 相似文献
64.
65.
Wallenius J Uuksulainen T Salonen K Rautio J Eerikäinen T 《Bioprocess and biosystems engineering》2011,34(9):1169-1176
In this study, Lactobacillus rhamnosus, a renowned probiotic, was cultivated in fluctuating environment. Base gradients caused by a pH control in an industrial
process and temperature gradients caused by uneven heating were simulated with a scale-down method. A pH gradient was created
in a plug flow reactor (PFR). Expression of pH stress-related genes (atpA, aldB, cfa, groEL, hrcA and pstS) were studied as a relative gene expression study using ldhD as a reference gene. Expression measurements were carried out with the TRAC method. The responses of groEL, hrcA and atpA genes to temperature and pH changes were observed. The expression of phosphate uptake system-related pstS gene was induced almost linearly in the chemostat cultivation experiments when the base gradient in the PFR was increased.
Correlations between the results from gene expression studies and freeze stability or acid stress survival were studied. However,
by measuring the expression of these genes, we were not able to predict eventual freeze stability or survival from the acid
stress test. 相似文献
66.
Wessman M Forsblom C Kaunisto MA Söderlund J Ilonen J Sallinen R Hiekkalinna T Parkkonen M Maxwell AP Tarnow L Parving HH Hadjadj S Marre M Peltonen L Groop PH;FinnDiane Study Group 《PloS one》2011,6(9):e24053
Background
Diabetic nephropathy (DN) affects about 30% of patients with type 1 diabetes (T1D) and contributes to serious morbidity and mortality. So far only the 3q21–q25 region has repeatedly been indicated as a susceptibility region for DN. The aim of this study was to search for new DN susceptibility loci in Finnish, Danish and French T1D families.Methods and Results
We performed a genome-wide linkage study using 384 microsatellite markers. A total of 175 T1D families were studied, of which 94 originated from Finland, 46 from Denmark and 35 from France. The whole sample set consisted of 556 individuals including 42 sib-pairs concordant and 84 sib-pairs discordant for DN. Two-point and multi-point non-parametric linkage analyses were performed using the Analyze package and the MERLIN software. A novel DN locus on 22q11 was identified in the joint analysis of the Finnish, Danish and French families by genome-wide multipoint non-parametric linkage analysis using the Kong and Cox linear model (NPLpairs LOD score 3.58). Nominal or suggestive evidence of linkage to this locus was also detected when the three populations were analyzed separately. Suggestive evidence of linkage was found to six additional loci in the Finnish and French sample sets.Conclusions
This study identified a novel DN locus at chromosome 22q11 with significant evidence of linkage to DN. Our results suggest that this locus may be of importance in European populations. In addition, this study supports previously indicated DN loci on 3q21–q25 and 19q13. 相似文献67.
Raija Uusitalo-Sepp?l? Reetta Huttunen Janne Aittoniemi Pertti Koskinen Aila Leino Tero Vahlberg Esa M. Rintala 《PloS one》2013,8(1)
Background
Early diagnostic and prognostic stratification of patients with suspected infection is a difficult clinical challenge. We studied plasma pentraxin 3 (PTX3) upon admission to the emergency department in patients with suspected infection.Methods
The study comprised 537 emergency room patients with suspected infection: 59 with no systemic inflammatory response syndrome (SIRS) and without bacterial infection (group 1), 67 with bacterial infection without SIRS (group 2), 54 with SIRS without bacterial infection (group 3), 308 with sepsis (SIRS and bacterial infection) without organ failure (group 4) and 49 with severe sepsis (group 5). Plasma PTX3 was measured on admission using a commercial solid-phase enzyme-linked immunosorbent assay (ELISA).Results
The median PTX3 levels in groups 1–5 were 2.6 ng/ml, 4.4 ng/ml, 5.0 ng/ml, 6.1 ng/ml and 16.7 ng/ml, respectively (p<0.001). The median PTX3 concentration was higher in severe sepsis patients compared to others (16.7 vs. 4.9 ng/ml, p<0.001) and in non-survivors (day 28 case fatality) compared to survivors (14.1 vs. 5.1 ng/ml, p<0.001). A high PTX3 level predicted the need for ICU stay (p<0.001) and hypotension (p<0.001). AUCROC in the prediction of severe sepsis was 0.73 (95% CI 0.66–0.81, p<0.001) and 0.69 in case fatality (95% CI 0.58–0.79, p<0.001). PTX3 at a cut-off level for 14.1 ng/ml (optimal cut-off value for severe sepsis) showed 63% sensitivity and 80% specificity. At a cut-off level 7.7 ng/ml (optimal cut-off value for case fatality) showed 70% sensitivity and 63% specificity in predicting case fatality on day 28.In multivariate models, high PTX3 remained an independent predictor of severe sepsis and case fatality after adjusting for potential confounders.Conclusions
A high PTX3 level on hospital admission predicts severe sepsis and case fatality in patients with suspected infection. 相似文献68.
Helena Tossavainen Satu H. Helppolainen Juha A. E. Määttä Tero Pihlajamaa Vesa P. Hytönen Markku S. Kulomaa Perttu Permi 《Biomolecular NMR assignments》2013,7(1):35-38
Avidin is a homotetrameric ~56 kDa protein found in chicken egg white. Avidin’s ability to bind biotin with a very high affinity has widely been exploited in biotechnological applications. Protein engineering has further diversified avidin’s feasibility. ChiAVD(I117Y) is a product of rational protein engineering. It is a hyperthermostable synthetic hybrid of avidin and avidin-related protein 4 (AVR4). In this chimeric protein a 23-residue segment in avidin has been replaced with the corresponding sequence found in AVR4, and a point mutation at subunit interface 1–3 (and 2–4) has been introduced. Here we report the backbone and sidechain resonance assignments of the biotin-bound form of ChiAVD(I117Y) as well as the backbone resonance assignments of the free form. 相似文献
69.
Mikko Taina Ritva Vanninen Marja Hedman Pekka J?k?l? Satu K?rkk?inen Tero Tapiola Petri Sipola 《PloS one》2013,8(11)
Background
Ischemic strokes without a well-defined etiology are labeled as cryptogenic, and account for 30–40% of strokes in stroke registries. The left atrial appendage (LAA) is the most typical origin for intracardiac thrombus formation when associated with atrial fibrillation. Here, we examined whether increased LAA volume detected with cardiac computed tomography (cCT) constitutes a risk factor in cryptogenic stroke patients.Methods
This study included 82 stroke/TIA patients (57 males; mean age, 58 years) with a diagnosis of cryptogenic stroke after extensive radiological and cardiological investigations. Cases were classified using the TOAST criteria modified by European Association of Echocardiography recommendations for defining cardiac sources of embolism. Forty age- and gender-matched control subjects without cardiovascular diseases were selected for pair-wise comparisons (21 males; mean age, 54 years). LAA volume adjusted for body surface area was measured three dimensionally by tracing the LAA borders on electrocardiogram-gated CT slices.Results
In control subjects, mean LAA volume was 3.4±1.1 mL/m2. Mean+2SD, which was considered the upper limit for normal LAA volume was 5.6 mL/m2. In paired Student t-test between the patient group and matched controls, LAA volume was 67% larger in cryptogenic stroke/TIA patients (5.7±2.0 mL/m2 vs. 3.4±1.1 mL/m2; P<0.001). Forty-five (55%) patients with cryptogenic stroke/TIA had enlarged LAA.Conclusion
LAA is significantly enlarged in more than half of patients with cryptogenic stroke/TIA. LAA thrombosis may contribute to the pathogenesis of stroke in patients considered to have cryptogenic stroke after conventional evaluation. 相似文献70.
Pauliina Repo Johannes E. Jntti Reetta‐Stiina Jrvinen Elina S. Rantala Martin Tll Virpi Raivio Tero T. Kivel Joni A. Turunen 《Pigment cell & melanoma research》2020,33(5):756-762
Uveal melanoma (UM) is a rare intraocular cancer with the highest incidence in northern latitudes. Metastases develop in approximately 50% of patients, whereafter the median survival is 13 months. Generally, the mutation burden of these tumors is low. Germline variants predisposing to UM have been previously described in BRCA1‐associated protein 1 (BAP1). Recently, germline and somatic loss‐of‐function (LOF) variants in the methyl‐CpG‐binding domain 4 (MBD4) gene have been found to cause a hypermutated UM, and MBD4 also has been put forward as a gene predisposing to UM. We sequenced for MBD4 germline variants in 440 Finnish patients with UM and identified seven rare exonic missense variants in 16 (3.6%) patients, of which one likely alters MBD4 function. The frequency of likely pathogenic variants in our cohort is 0.23% (1/432; 95% CI, 0.01–1.28). We identified no LOF variants though their frequency in the Finnish population is 0.052%. Thus, our data do not support the suggestion that MBD4 germline variants predispose to UM. Somatic loss of MBD4 might modify the mutational burden in UM and change its response to immune checkpoint inhibitors. 相似文献