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71.
Kari Seppänen Reino Laatikainen Jukka T. Salonem Marjatta Kantola Simo Lötjönen Mikko Harri Llisa Nüurminen Jari Kaikkomem Kristiima Nyyssönen 《Biological trace element research》1998,65(3):197-210
The mercury-binding capacity of seleno-DL-methionine and selenium dioxide was assessed in male Wistar rats. Mercury was supplied
as fish loaves made of northern pike or rainbow trout. We used a selenium concentration of 3.4 mg/kg fish, about sixfold compared
to the equivalent quantity of mercury. Seleno-DL-methionine had a tendency to increase both methyl mercury and total mercury
in blood, although it also seemed to reduce the proportion of methyl mercury of total mercury. Selenium dioxide lowered mercury
levels by 24–29% both in the blood and in the liver of rats that were fed with northern pike. 相似文献
72.
Simo O Lee VP Davis AS Kreutz C Gross PH Jones PR Michael K 《Carbohydrate research》2005,340(4):557-566
The glycosylamines of O-acetyl-protected GlcNAc and chitobiose, as well as two partially unprotected 1-C-aminomethyl glucosides, were photochemically coupled with orthogonally protected N-aspartyl-5-bromo-7-nitroindoline derivatives. The reactions proceeded under neutral conditions by irradiation with near-UV light. The glycosyl asparagines with N- or C-glycosyl linkages were afforded in 60-85% yield on a 10-70 mg scale. Moreover, the ability of a highly photoreactive N-glutamyl-4-methoxy-7-nitroindoline derivative to acylate amino saccharides was tested. Upon irradiation in the presence of a dimeric 1-C-aminomethyl glycoside, or a glycosylamine, the corresponding glycosyl glutamines were obtained in 50% and 30% yield, respectively. Preparations of the photoreactive aspartates and the 1-C-aminomethyl glycosides are also described. 相似文献
73.
Eremin KO Kudrin VS Saransaari P Oja SS Grivennikov IA Myasoedov NF Rayevsky KS 《Neurochemical research》2005,30(12):1493-1500
Corticotrophin (ACTH) and its analogues, particularly Semax (Met-Glu-His-Phe-Pro-Gly-Pro), demonstrate nootropic activity.
Close functional and anatomical links have been established between melanocortinergic and monoaminergic brain systems. The
aim of present work was to investigate the effects of Semax on neurochemical parameters of dopaminergic- and serotonergic
systems in rodents. The tissue content of 5-hydroxyindoleacetic acid (5-HIAA) in the striatum was significantly increased
(+25%) 2 h after Semax administration. The extracellular striatal level of 5-HIAA gradually increased up to 180% within 1–4 h
after Semax (0.15 mg/kg, ip) administration. This peptide alone failed to alter the tissue and extracellular concentrations
of dopamine and its metabolites. Semax injected 20 min prior d-amphetamine dramatically enhanced the effects of the latter on the extracellular level of dopamine and on the locomotor activity
of animals. Our results reveal the positive modulatory effect of Semax on the striatal serotonergic system and the ability
of Semax to enhance both the striatal release of dopamine and locomotor behavior elicited by d-amphetamine.
Special issue dedicated to Dr. Simo S. Oja. 相似文献
74.
Kilpimaa J Van de Casteele T Jokinen I Mappes J Alatalo RV 《Evolution; international journal of organic evolution》2005,59(11):2483-2489
Host parasite coevolution assumes pathogen specific genetic variation in host immune defense. Also, if immune function plays a role in the evolution of life history, allocation to immune function should be heritable. We conducted a cross-fostering experiment to test the relative importance of genetic and environmental sources of variation in T-cell mediated inflammatory response and antigen specific antibody responses in the great tits Parus major. Cell mediated response was measured during the nestling period and antibody response against two novel antigens was measured in two-month-old juveniles raised in a laboratory. We found no effect of nest of origin, but a strong effect of rearing environment on cell mediated response. In contrast, we found a large effect of nest of origin on antibody response to both, diphtheria and tetanus antigens suggesting genetic variation. In a model where responses to both antigens were analyzed simultaneously, we found a significant origin-by-antigen interaction, suggesting that genetic variation in antibody responses is specific to particular antigens. Large genetic variation in antibody responses found in this study suggests that host immune defense may evolve and specificity of genetic variation in antibody responses suggests that host defense may be pathogen specific as models of host-parasite coevolution suggest. Our results also suggest that different immune traits are to some degree independent and outcome of the interactions between immune function and the environment may depend on the particular immune trait measured. 相似文献
75.
Simo G Herder S Njiokou F Asonganyi T Tilley A Cuny G 《Experimental parasitology》2005,110(4):353-362
To better understand the epidemiology of sleeping sickness in the Central African sub-region, notably the heterogeneity of Human African Trypanosomiasis (HAT) foci, the mobile genetic element PCR (MGE-PCR) technique was used to genotype Trypanosoma brucei s.l. (T. brucei s.l.) isolates from this sub-region. Using a single primer REV B, which detects positional variation of the mobile genetic element RIME, via amplification of flanking regions, MGE-PCR revealed a micro genetic variability between Trypanosoma brucei gambiense (T. b. gambiense) isolates from Central Africa. The technique also revealed the presence of several T. b. gambiense genotypes and allowed the identification of minor and major ubiquitous genotypes in HAT foci. The presence of several T. b. gambiense genotypes in HAT foci may explain the persistence and the resurgence phenomena of the disease and also the epidemic and the endemic status of some Central African sleeping sickness foci. The MGE-PCR technique represents a simple, rapid, and specific method to differentiate Central African T. brucei s.l. isolates. 相似文献
76.
Jukka Jokinen Hanna Rinta-Kokko Lotta Siira Arto A. Palmu Mikko J. Virtanen Hanna Nohynek Anni Virolainen-Julkunen Maija Toropainen J. Pekka Nuorti 《PloS one》2015,10(3)
Background
The ten-valent pneumococcal conjugate vaccine (PCV10) was introduced into the Finnish National Vaccination Program (NVP) in September 2010 with a 2+1 schedule (3, 5, 12 months) without catch-up vaccinations. We evaluated the direct and indirect effects of PCV10 on invasive pneumococcal disease (IPD) among children ≤5 years of age during the first three years after NVP introduction.Methods
We conducted a population-based, observational follow-up study. The cohort of vaccine-eligible children (all children born June 1, 2010 or later) was followed from 3 months of age until the end of 2013. For the indirect effect, another cohort of older children ineligible for PCV10 vaccination was followed from 2011 through 2013. Both cohorts were compared with season- and age-matched reference cohorts before NVP introduction. National, population-based laboratory surveillance data were used to compare culture-confirmed serotype-specific IPD rates in the vaccine target and reference cohorts by using Poisson regression models.Results
The overall IPD rate among vaccine-eligible children was reduced by 80% (95%CI 72 to 85); the reduction in vaccine-type IPD was 92% (95%CI 86 to 95). However, a non-significant increase in non-vaccine type IPD was observed. During 2012–2013, we also observed a 48% (95%CI 18 to 69) reduction in IPD among unvaccinated children 2 to 5 years of age, which was mostly attributable to the ten vaccine serotypes.Conclusions
This is the first population-based study investigating the impact of PCV10 introduction without prior PCV7 use. A substantial decrease in IPD rates among vaccine-eligible children was observed. A smaller and temporally delayed reduction among older, unvaccinated children suggests that PCV10 also provides indirect protection against vaccine-type IPD. Changes in serotype distribution warrant continuous monitoring of potential increases in non-vaccine serotypes. 相似文献77.
Ugutz Unzueta Felicitas Vázquez Giulia Accardi Rosa Mendoza Verónica Toledo-Rubio Maria Giuliani Filomena Sannino Ermenegilda Parrilli Ibane Abasolo Simo Schwartz Jr. Maria L. Tutino Antonio Villaverde José L. Corchero Neus Ferrer-Miralles 《Applied microbiology and biotechnology》2015,99(14):5863-5874
78.
Rinez Thapa Subhasish Mondal Joakim Riikonen Jimi Rantanen Simo Nkki Tuomo Nissinen Ale Nrvnen Vesa-Pekka Lehto 《PLoS neglected tropical diseases》2021,15(6)
Visceral leishmaniasis is a vector-borne protozoan infection that is fatal if untreated. There is no vaccination against the disease, and the current chemotherapeutic agents are ineffective due to increased resistance and severe side effects. Buparvaquone is a potential drug against the leishmaniases, but it is highly hydrophobic resulting in poor bioavailability and low therapeutic efficacy. Herein, we loaded the drug into silicon nanoparticles produced from barley husk, which is an agricultural residue and widely available. The buparvaquone-loaded nanoparticles were several times more selective to kill the intracellular parasites being non-toxic to macrophages compared to the pure buparvaquone and other conventionally used anti-leishmanial agents. Furthermore, the in vivo results revealed that the intraperitoneally injected buparvaquone-loaded nanoparticles suppressed the parasite burden close to 100%. By contrast, pure buparvaquone suppressed the burden only by 50% with corresponding doses. As the conclusion, the biogenic silicon nanoparticles are promising carriers to significantly improve the therapeutic efficacy and selectivity of buparvaquone against resistant visceral leishmaniasis opening a new avenue for low-cost treatment against this neglected tropical disease threatening especially the poor people in developing nations. 相似文献
79.
Gupta RD Goldsmith M Ashani Y Simo Y Mullokandov G Bar H Ben-David M Leader H Margalit R Silman I Sussman JL Tawfik DS 《Nature chemical biology》2011,7(2):120-125
Organophosphate nerve agents are extremely lethal compounds. Rapid in vivo organophosphate clearance requires bioscavenging enzymes with catalytic efficiencies of >10(7) (M(-1) min(-1)). Although serum paraoxonase (PON1) is a leading candidate for such a treatment, it hydrolyzes the toxic S(p) isomers of G-agents with very slow rates. We improved PON1's catalytic efficiency by combining random and targeted mutagenesis with high-throughput screening using fluorogenic analogs in emulsion compartments. We thereby enhanced PON1's activity toward the coumarin analog of S(p)-cyclosarin by ~10(5)-fold. We also developed a direct screen for protection of acetylcholinesterase from inactivation by nerve agents and used it to isolate variants that degrade the toxic isomer of the coumarin analog and cyclosarin itself with k(cat)/K(M) ~ 10(7) M(-1) min(-1). We then demonstrated the in vivo prophylactic activity of an evolved variant. These evolved variants and the newly developed screens provide the basis for engineering PON1 for prophylaxis against other G-type agents. 相似文献
80.