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71.
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
72.
Reginald Quansah Maritta S. Jaakkola Timo T. Hugg Sirpa A M. Heikkinen Jouni J. K. Jaakkola 《PloS one》2012,7(11)
Context
Studies from different geographical regions have assessed the relations between indoor dampness and mold problems and the risk of asthma, but the evidence has been inconclusive.Objective
To assess the relations between indicators of indoor dampness and mold problems and the risk of developing new asthma, and to investigate whether such relations differ according to the type of exposure.Data sources
A systematic literature search of PubMed database from 1990 through March 2012 and the reference lists of recent reviews and of relevant articles identified in our search.Study selection
Cohort/longitudinal and incident case-control studies assessing the relation between mold/dampness and new asthma were included.Data extraction
Three authors independently evaluated eligible articles and extracted relevant information using a structured form.Synthesis
Sixteen studies were included: 11 cohort and 5 incident case-control studies. The summary effect estimates (EE) based on the highest and lowest estimates for the relation between any exposure and onset of asthma were 1.50 (95% confidence interval [CI] 1.25–1.80, random-effects model, Q-statistic 38.74 (16), P = 0.001) and 1.31 (95% CI 1.09–1.58, random-effects model, Q-statistic 40.08 (16), P = 0.000), respectively. The summary effect estimates were significantly elevated for dampness (fixed-effects model: EE 1.33, 95% CI 1.12–1.56, Q-statistic 8.22 (9), P = 0.413), visible mold (random-effects model; EE 1.29, 95% CI 1.04–1.60, 30.30 (12), P = 0.001), and mold odor (random-effects model; EE 1.73, 95% CI 1.19–2.50, Q-statistics 14.85 (8), P = 0.038), but not for water damage (fixed-effects model; EE 1.12, 95% CI 0.98–1.27). Heterogeneity was observed in the study-specific effect estimates.Conclusion
The evidence indicates that dampness and molds in the home are determinants of developing asthma. The association of the presence of visible mold and especially mold odor to the risk of asthma points towards mold-related causal agents. 相似文献73.
Kati?HanhinevaEmail author Harri?Kokko Sirpa?K?renlampi 《In vitro cellular & developmental biology. Plant》2005,41(6):826-831
Summary A temporary immersion bioreactor system (TIB system) provides a convenient and efficient way to propagate plant material in vitro while requiring significantly lower labor input than conventional methods. The applicability of a TIB system for adventitious
shoot regeneration from strawberry leaf explants was studied. Five commercial cultivars, i.e. Bounty, Jonsok, Korona, Polka,
and Zephyr, were propagated in regeneration medium in commercially available TIB bioreactors (RITA?) and, for comparison, on the same medium solidified with agar. The TIB system proved to be well suited for shoot propagation
and for subsequent subculture of the developing plantlets. Regeneration frequencies were 70±8 to 94±2% and 83±5 to 92±3% in
the TIB system and on semi-solid medium, respectively. The labor time taken by the TIB system was less than half of the time
required for handling plant material for cultivation on semi-solid medium. This system thus provides a convenient method that
could be adopted for commercial in vitro propagation or for regeneration of transgenic strawberry cultivars. 相似文献
74.
75.
Periplakin gene targeting reveals a constituent of the cornified cell envelope dispensable for normal mouse development 下载免费PDF全文
Aho S Li K Ryoo Y McGee C Ishida-Yamamoto A Uitto J Klement JF 《Molecular and cellular biology》2004,24(14):6410-6418
The members of the plakin family of proteins serve as epidermal cytolinkers and components of cell-cell and cell-matrix adhesion complexes, i.e., desmosomes and hemidesmosomes, respectively. Periplakin is a recently characterized member of this family. Human and mouse periplakin genomic loci are conserved, and the proteins are highly homologous, suggesting a role for periplakin in vertebrate physiology. In order to evaluate the functional role of periplakin, we generated periplakin null mice through targeted homologous recombination of mouse embryonic stem cells, followed by development of Ppl(-/-) mice. Mice homozygous for the targeted allele were born in the expected Mendelian frequency, developed normally, possessed grossly normal epidermis and hair, and were healthy and fertile. The epidermal barrier appeared to develop normally during fetal days E15.5 to E16.5, and the cornified envelope and desmosomes in the newborn mice were ultrastructurally normal. No compensatory increase in the expression of other epithelial proteins was detected in the neonatal mouse epidermis lacking periplakin. Consequently, the primary role of periplakin may not relate to the physiology of the cornified cell envelope in epidermal keratinocytes but may reside in the challenges, which normal laboratory mice do not encounter. 相似文献
76.
Koistinen KM Soininen P Venäläinen TA Häyrinen J Laatikainen R Peräkylä M Tervahauta AI Kärenlampi SO 《Phytochemistry》2005,66(21):2524-2533
PR-10c is a unique member of PR-10 proteins in birch, since it is the only one known to be post-translationally modified by glutathione and is not constitutively expressed in pollen. Both reduced and S-glutathiolated forms of PR-10c show low ribonuclease activity. However, the major function of the protein is apparently not yet resolved. Our protein-ligand interaction studies with saturation transfer difference (STD) NMR revealed that PR-10c interacts with several biologically important molecules, including cytokinin, flavonoid glycosides, sterols and emodin. Competition study with deoxycholate and kinetin revealed no statistically significant binding interference, indicating that these ligands have different binding sites in PR-10c. Ligand docking studies with a molecular model of PR-10c support the STD NMR results of ligand binding and binding epitopes, suggesting that there are three potential binding sites in PR-10c: two in the hydrophobic cavity and one in the glycine-rich loop. Our docking calculations suggested that only kinetin interacts with the glycine-rich loop, the binding occurring through its adenine moiety. Clear ligand specificity could be observed in the binding of nucleotide derivatives. S-glutathiolation of PR-10c did not affect kinetin binding. The present results suggest that birch PR-10c is a multifunctional protein, which has diverse roles in plant stress responses. 相似文献
77.
78.
Päivi Kurttio Karri Seppä Kari Pasanen Toni Patama Anssi Auvinen Eero Pukkala Sirpa Heinävaara Hannu Arvela Timo Hakulinen 《Cancer epidemiology》2013,37(5):585-592
Aim: We studied whether incidence of all cancer sites combined was associated with the radiation exposure due to fallout from the Chernobyl accident in Finland. An emphasis was on the first decade after the accident to assess the suggested “promotion effect”. Methods: The segment of Finnish population with a stable residence in the first post-Chernobyl year (2 million people) was studied. The analyses were based on a 250 m × 250 m grid squares covering all of Finland and all cancer cases except cancers of the breast, prostate and lung. Cancer incidence in four exposure areas (based on first-year dose due to external exposure <0.1 mSv, 0.1–1.3, 0.3–0.5, or ≥0.5 mSv) was compared before the Chernobyl accident (1981–1985) and after it (1988–2007) taking into account cancer incidence trends for a longer period prior to the accident (since 1966). Results: There were no systematic differences in the cancer incidence in relation to radiation exposure in any calendar period, or any subgroup by sex or age at accident. Conclusion: The current large and comprehensive cohort analysis of the relatively low levels of the Chernobyl fallout in Finland did not observe a cancer promotion effect. 相似文献
79.
Elisabel Marquez José Pavia Sirpa Laukonnen Francisco Martos Aurelio Gomez Francisca Rius 《Chronobiology international》2013,30(4):277-282
The binding of different ligands to muscarinic receptors in the centra) nervous system is regulated by several factors. Among these are the administration of drugs, disease, ontogeny or aging. Studies carried out in rat brains have demonstrated changes in the density of the muscarinic receptors at different times of the day. These changes might be related to variations in the circadian rhythms. In this work we have studied the binding of the [3H]-N-methyl-escopolamine, the agonist carbachol and the antagonist pirenzepine to muscarinic receptors in rat forebrains at 10.00,14.00,18.00,22.00,02.00 and 06.00 hr. We have observed changes in the density of muscarinic receptors but not changes in affinity to the radioligand. The Bmax values obtained by saturation studies were maximum at 14.00 hr and minimum at 02.00 hr (p < 0.05 Mann-Whitney's test). Inhibition studies in the presence of the non-selective agonist carbachol and the selective antagonist pirenzepine, at the same time-points, did not show statistically significant changes in the Bmax values. These data indicate that changes in the Bmax values are only observed in the total population of muscarinic receptors and are not due to modifications in the subtypes of muscarinic receptors nor to the different affinity states of agonist binding. 相似文献
80.
Anna‐Maija Hannele Syrjälä Pekka Ylöstalo Piia Ruoppi Kaija Komulainen Sirpa Hartikainen Raimo Sulkava Matti Knuuttila 《Gerodontology》2012,29(1):36-42
doi: 10.1111/j.1741‐2358.2010.00396.x Dementia and oral health among subjects aged 75 years or older Objective: To study the association between diagnosed dementia and oral health, focusing on the type of dementia, among an elderly population aged 75 years or older. Background: Elderly people with dementia are at risk from oral diseases, but to date, only a few studies have analysed the association between type of dementia and oral health, and their results are inconclusive. Materials and methods: This cross‐sectional study is based on the Geriatric multi‐disciplinary strategy (Gems) study that included 76 demented and 278 non‐demented subjects. The data were collected by means of an interview and an oral clinical examination. The type of dementia was diagnosed according to DSM‐IV criteria. Poisson’s and logistic regression models were used to determine relative risks (RR), odds ratios (OR) and 95% confidence limits (CI). Results: Our results showed that patients with Alzheimer’s disease and those with other types of dementia had an increased likelihood of having carious teeth, teeth with deep periodontal pockets, and poor oral and denture hygiene, compared with non‐demented persons. The results showed that the type of dementia does not seem to be an essential determinant of oral health. Conclusions: Among the elderly aged 75 years or older, patients with Alzheimer’s disease or other types of dementia are at increased risk of poor oral health and poor oral hygiene. 相似文献