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1.
V ronique Cruciani Karen-Marie Heintz Trine Hus y Eivind Hovig David J. Warren Svein-Ole Mikalsen 《Cell communication & adhesion》2004,11(5):155-171
The open reading frames of 17 connexins from Syrian hamster (using tissues) and 16 connexins from the Chinese hamster cell line V79, were fully (Cx30, Cx31, Cx37, Cx43 and Cx45) or partially sequenced. We have also detected, and partially sequenced, seven rat connexins that previously were unavailable. The expression of connexin genes was examined in some hamster organs and cultured hamster cells, and compared with wild-type mouse and the cancer-prone Min mouse. Although the expression patterns were similar for most organs and connexins in hamster and mouse, there were also some prominent differences (Cx29 and 30.3 in testis; Cx31.1 and 32 in eye; Cx46 in brain, kidney and testis; Cx47 in kidney). This suggests that some connexins have species-specific expression profiles. In contrast, there were minimal differences in expression profiles between wild type and Min mice. Species-specific expression profiles should be considered in attempts to make animal models of human connexin-associated diseases. 相似文献
2.
Jan O. Gordeladze Trine Haugen Eivind J. Paulssen Ruth H. Paulssen 《Bioscience reports》1996,16(1):65-74
The presence of the pertussis toxin (PTX) insensitive GTP-binding proteins (G-proteins) Gq and/or G11 has been demonstrated in three different prolactin (PRL) and growth hormone (GH) producing pituitary adenoma cell lines. Immunoblocking of their coupling to hormone receptors indicates that Gq and/or G11 confer throliberin (TRH) responsive phospholipase C (PL-C) activity in these cells. The contention was substantiated by immunoprecipitation analyses snowing that anti Gq/11-sera coprecipitated PL-C activity. In essence, only Gq/11 (but neither Gi2, Gi3 nor Go) seems to mediate the TRH-sensitive PL-C activity, while Go may be coupled to a basal or constitutive PL-C activity. Immunoblocking studies imply that the B-complex also, to some extent, may stimulate GH3 pituitary cell line PL-C activity. Finally, the steady state levels of Gq/11 mRNA and protein were downregulated upon long term exposure of the GH3 cells to TRH (but not to vasoactive intestinal peptide = VIP). 相似文献
3.
Joan Thiesen Torben S. Christensen Thomas G. Kristensen Rikke D. Andersen Brit Brunoe Trine K. Gregersen Mikkel Thrane Bo P. Weidema 《The International Journal of Life Cycle Assessment》2008,13(2):104-114
Goal, Scope and Background Traditionally, comparative life cycle assessments (LCA) have not considered rebound effects, for instance in case of significant
price differences among the compared products. No justifications have been made for this delimitation in scope. This article
shows that price differences and the consequent effects of marginal consumer expenditure may influence the conclusions of
comparative LCA significantly. We also show that considerations about rebound effects of price differences can be included
in LCAs.
Methods The direct rebound effect of a price difference is marginal consumption. Based on statistical data on private consumption
in different income groups (Statistics Denmark 2005a, 2005b), the present article provides an estimate of how an average Danish
household will spend an additional 1 DKK for further consumer goods, when the household has gained money from choosing a cheaper
product alternative. The approach is to use marginal income changes and the following changes in consumption patterns as an
expression for marginal consumption. Secondly, the environmental impact potentials related to this marginal consumption are
estimated by the use of environmental impact intensity data from an IO-LCA database (Weidema et al. 2005). Finally, it is
discussed whether, and in which ways the conclusions of comparative LCAs can be affected by including the price difference
between product alternatives. This is elucidated in a case study of a comparative LCA screening of two different kinds of
Danish cheese products (Fricke et al. 2004).
Results Car purchase and driving, use and maintenance of dwelling, clothing purchase and insurance constitutes the largest percentages
of the marginal consumption. In a case study of two cheeses, the including the impact potentials related to the price difference
results in significant changes in the total impact potentials. Considering the relatively small price difference of the two
products, it is likely also to have a significant influence on the results of comparative LCAs more generally.
Discussion The influence of marginal consumption in comparative LCAs is relevant to consider in situations with large differences in
the price of the product alternatives being compared, and in situations with minor differences in the impact potentials related
to the alternatives. However, different uncertainties are linked to determining the pattern for marginal consumption and the
environmental impact potential related to this. These are first of all related to the method used, but also include inaccurate
data of consumption in households, aggregation and weighting of income groups, aggregation of product groups, estimation and
size of the price difference, and the general applicability of the results.
Conclusion Incorporating marginal consumption in consequential LCAs is possible in practice. In the case study used, including the rebound
effects of the price difference has a significant influence on the result of the comparative LCA, as the result for the impact
categories acidification and nutrient enrichment changes in favour of the expensive product.
Recommendations and Perspectives It is recommended that the rebound effects of price differences should be included more frequently in LCAs. In order to ensure
this, further research in marginal consumption and investment patterns and IO data for different countries or regions is required.
Furthermore, this study does not consider the economic distributional consequences of buying an expensive product instead
of a cheaper product (e.g. related to how the profit is spent by those who provided the product). It should also be noted,
that more expensive products not necessarily result in less consumption, as those who provided the product also will spend
the money they have earned from the sale. Ideally, these consequences should also be further investigated. Likewise, the development
of databases to include marginal consumption in PC-tools is needed. In general, considerations of marginal consumption would
favour expensive product alternatives, depending, however, on the type of consumer.
ESS-Submission Editor: Dr. David Hunkeler (david.hunkeler@aquaplustech.ch) 相似文献
4.
The abundance of potential denitrifiers in full-scale wastewater treatment plants with biological nitrogen and phosphorus removal was investigated by FISH and various oligonucleotide probes. The potential denitrifiers were characterized as probe-defined populations that were able to consume radiolabelled substrate with oxygen, nitrate and nitrite as electron acceptor as determined by microautoradiography. The most abundant potential denitrifiers were related to the genera Aquaspirillum, Azoarcus, Thauera and Rhodocyclus, all within the Betaproteobacteria. They made up 20-49% of all bacteria in most of the 17 nitrogen removal plants investigated and were hardly present in four plants without denitrification. The ecophysiology of Aquaspirillum, Azoarcus and Thauera-related bacteria was consistent within each probe-defined group in the plants investigated. These three groups showed distinct physiological differences, with the Aquaspirillum-related bacteria appearing as the most specialized one, consuming only amino acids among the substrates tested, and Thauera as the most versatile consuming some volatile fatty acids, ethanol and amino acids. The coexistence of Aquaspirillum, Azoarcus and Thauera-related bacteria in a range of treatment plants with differences in wastewater, design and operation suggest that the populations ensure a functional stability of the plants by occupying different ecological niches related to the carbon transformation. 相似文献
5.
Louise S. Dalb?ge Dorthe L. C. Almholt Trine S. R. Neerup Efstathios Vassiliadis Niels Vrang Lars Pedersen Keld Fosgerau Jacob Jelsing 《PloS one》2013,8(12)
Aim
To characterise changes in pancreatic beta cell mass during the development of diabetes in untreated male C57BLKS/J db/db mice.Methods
Blood samples were collected from a total of 72 untreated male db/db mice aged 5, 6, 8, 10, 12, 14, 18, 24 and 34 weeks, for measurement of terminal blood glucose, HbA1c, plasma insulin, and C-peptide. Pancreata were removed for quantification of beta cell mass, islet numbers as well as proliferation and apoptosis by immunohistochemistry and stereology.Results
Total pancreatic beta cell mass increased significantly from 2.1 ± 0.3 mg in mice aged 5 weeks to a peak value of 4.84 ± 0.26 mg (P < 0.05) in 12-week-old mice, then gradually decreased to 3.27 ± 0.44 mg in mice aged 34 weeks. Analysis of islets in the 5-, 10-, and 24-week age groups showed increased beta cell proliferation in the 10-week-old animals whereas a low proliferation is seen in older animals. The expansion in beta cell mass was driven by an increase in mean islet mass as the total number of islets was unchanged in the three groups.Conclusions/Interpretation
The age-dependent beta cell dynamics in male db/db mice has been described from 5-34 weeks of age and at the same time alterations in insulin/glucose homeostasis were assessed. High beta cell proliferation and increased beta cell mass occur in young animals followed by a gradual decline characterised by a low beta cell proliferation in older animals. The expansion of beta cell mass was caused by an increase in mean islet mass and not islet number. 相似文献6.
Miriam Ragle Aure Suvi-Katri Leivonen Thomas Fleischer Qian Zhu Jens Overgaard Jan Alsner Trine Tramm Riku Louhimo Grethe I Grenaker Aln?s Merja Per?l? Florence Busato Nizar Touleimat J?rg Tost Anne-Lise B?rresen-Dale Sampsa Hautaniemi Olga G Troyanskaya Ole Christian Lingj?rde Kristine Kleivi Sahlberg Vessela N Kristensen 《Genome biology》2013,14(11):R126
Background
The global effect of copy number and epigenetic alterations on miRNA expression in cancer is poorly understood. In the present study, we integrate genome-wide DNA methylation, copy number and miRNA expression and identify genetic mechanisms underlying miRNA dysregulation in breast cancer.Results
We identify 70 miRNAs whose expression was associated with alterations in copy number or methylation, or both. Among these, five miRNA families are represented. Interestingly, the members of these families are encoded on different chromosomes and are complementarily altered by gain or hypomethylation across the patients. In an independent breast cancer cohort of 123 patients, 41 of the 70 miRNAs were confirmed with respect to aberration pattern and association to expression. In vitro functional experiments were performed in breast cancer cell lines with miRNA mimics to evaluate the phenotype of the replicated miRNAs. let-7e-3p, which in tumors is found associated with hypermethylation, is shown to induce apoptosis and reduce cell viability, and low let-7e-3p expression is associated with poorer prognosis. The overexpression of three other miRNAs associated with copy number gain, miR-21-3p, miR-148b-3p and miR-151a-5p, increases proliferation of breast cancer cell lines. In addition, miR-151a-5p enhances the levels of phosphorylated AKT protein.Conclusions
Our data provide novel evidence of the mechanisms behind miRNA dysregulation in breast cancer. The study contributes to the understanding of how methylation and copy number alterations influence miRNA expression, emphasizing miRNA functionality through redundant encoding, and suggests novel miRNAs important in breast cancer. 相似文献7.
Peng Zhang Trine Nygaard Jørgensen Claus J. Loland Amy Hauck Newman 《Bioorganic & medicinal chemistry letters》2013,23(1):323-326
A novel fluorescent ligand was synthesized as a high-affinity, high specificity probe for visualizing the serotonin transporter (SERT). The rhodamine fluorophore was extended from an aniline substitution on the 5-position of the dihydroisobenzofuran ring of citalopram (2, 1-(3-(dimethylamino)propyl)-1-(4-fluorophenyl)-1,3-dihydroisobenzofuran-5-carbonitrile), using an ethylamino linker. The resulting rhodamine-labeled ligand 8 inhibited [3H]5-HT uptake in COS-7 cells (Ki = 225 nM) with similar potency to the tropane-based JHC 1-064 (1), but with higher specificity towards the SERT relative to the transporters for dopamine and norepinephrine. Visualization of the SERT with compound 8 was demonstrated by confocal microscopy in HEK293 cells stably expressing EGFP–SERT. 相似文献
8.
Introduction
Cerebral malaria (CM) is a potentially fatal cerebrovascular disease of complex pathogenesis caused by Plasmodium falciparum. Hydrogen sulfide (HS) is a physiological gas, similar to nitric oxide and carbon monoxide, involved in cellular metabolism, vascular tension, inflammation, and cell death. HS treatment has shown promising results as a therapy for cardio- and neuro- pathology. This study investigates the effects of fast (NaHS) and slow (GYY4137) HS-releasing drugs on the growth and metabolism of P. falciparum and the development of P. berghei ANKA CM. Moreover, we investigate the role of free plasma thiols and cell surface thiols in the pathogenesis of CM.Methods
P. falciparum was cultured in vitro with varying doses of HS releasing drugs compared with artesunate. Growth and metabolism were quantified. C57Bl/6 mice were infected with P. berghei ANKA and were treated with varying doses and regimes of HS-releasing drugs. Free plasma thiols and cell surface thiols were quantified in CM mice and age-matched healthy controls.Results
HS-releasing drugs significantly and dose-dependently inhibited P. falciparum growth and metabolism. Treatment of CM did not affect P. berghei growth, or development of CM. Interestingly, CM was associated with lower free plasma thiols, reduced leukocyte+erythrocyte cell surface thiols (infection day 3), and markedly (5-fold) increased platelet cell surface thiols (infection day 7).Conclusions
HS inhibits P. falciparum growth and metabolism in vitro. Reduction in free plasma thiols, cell surface thiols and a marked increase in platelet cell surface thiols are associated with development of CM. HS drugs were not effective in vivo against murine CM. 相似文献9.
Anne-Marie Lundsgaard Jacob B. Holm Kim A. Sjøberg Kirstine N. Bojsen-Møller Lene S. Myrmel Even Fjære Benjamin A.H. Jensen Trine S. Nicolaisen Janne R. Hingst Sine L. Hansen Sophia Doll Philip E. Geyer Atul S. Deshmukh Jens J. Holst Lise Madsen Karsten Kristiansen Jørgen F.P. Wojtaszewski Erik A. Richter Bente Kiens 《Cell metabolism》2019,29(1):50-63.e4
10.
Laura Kofoed Kjær Vanja Cejvanovic Trine Henriksen Torben Hansen Oluf Pedersen Cramer Kjeldahl Christensen 《Free radical research》2019,53(6):694-703
The relationship between RNA and DNA oxidation and pharmacological treatment has not been systematically investigated in patients with type 2 diabetes (T2D). We aimed to investigate the association between pharmacological treatments and levels of urinary markers of nucleic acid oxidation in T2D patients. Vejle Diabetes Biobank cohort data was nested into nationwide registry data. Multiple logistic regression was used to associate drug usage with risk of high (above median) RNA and DNA oxidation. Data from 2664 T2D patients (64% male, age range: 25–75) were included. Questionnaire-validated lipid lowering drug use was associated with low RNA oxidation (Odds ratio, OR 0.71, 95% CI: [0.59–0.87]). Insulin and non-specific antidiabetic drugs were associated with low DNA oxidation (insulin: OR 0.60, 95% CI [0.49–0.73]). Oral antidiabetics were associated with high DNA oxidation and RNA oxidation (OR 1.30, 95% CI [1.10–1.53] and OR 1.26, 95% CI [1.07–1.29]). Our findings indicate that diabetes-related drugs are associated with RNA and DNA oxidation and further studies are required to determine causality in T2D patients. 相似文献