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Cell interactions involving Notch signaling are required for the demarcation of tissue boundaries in both invertebrate and vertebrate development. Members of the Fringe gene family encode beta-1,3 N-acetyl-glucosaminyltransferases that function to refine the spatial localization of Notch-receptor signaling to tissue boundaries. In this paper we describe the isolation and characterization of the zebrafish (Danio rerio) homologue of the lunatic fringe gene (lfng). Zebrafish lfng is generally expressed in equivalent structures to those reported for the homologous chick and mouse genes. These sites include expression along the A-P axis of the neural tube, within the lateral plate mesoderm, in the presomitic mesoderm and the somites and in specific rhombomeres of the hindbrain; however, within these general expression domains species-specific differences in lfng expression exist. In mouse, Lfng is expressed in odd-numbered rhombomeres, whereas in zebrafish, expression occurs in even-numbered rhombomeres. In contrast to reports in both mouse and chicken embryos showing a kinematic cyclical expression of Lfng mRNA in the presomitic paraxial mesoderm, we find no evidence for a cyclic pattern of expression for the zebrafish lfng gene; instead, the zebrafish lfng is expressed in two static stripes within the presomitic mesoderm. Nevertheless, in zebrafish mutants affecting the correct formation of segment boundaries in the hindbrain and somites, lfng expression is aberrant or lost. 相似文献
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A New In Vitro Model to Study Cellular Responses after Thermomechanical Damage in Monolayer Cultures
Although electrosurgical instruments are widely used in surgery to cut tissue layers or to achieve hemostasis by coagulation (electrocautery), only little information is available concerning the inflammatory or immune response towards the debris generated. Given the elevated local temperatures required for successful electrocautery, the remaining debris is likely to contain a plethora of compounds entirely novel to the intracorporal setting. A very common in vitro method to study cell migration after mechanical damage is the scratch assay, however, there is no established model for thermomechanical damage to characterise cellular reactions. In this study, we established a new in vitro model to investigate exposure to high temperature in a carefully controlled cell culture system. Heatable thermostat-controlled aluminium stamps were developed to induce local damage in primary human umbilical vein endothelial cells (HUVEC). The thermomechanical damage invoked is reproducibly locally confined, therefore allowing studies, under the same experimental conditions, of cells affected to various degrees as well as of unaffected cells. We show that the unaffected cells surrounding the thermomechanical damage zone are able to migrate into the damaged area, resulting in a complete closure of the ‘wound’ within 48 h. Initial studies have shown that there are significant morphological and biological differences in endothelial cells after thermomechanical damage compared to the mechanical damage inflicted by using the unheated stamp as a control. Accordingly, after thermomechanical damage, cell death as well as cell protection programs were activated. Mononuclear cells adhered in the area adjacent to thermomechanical damage, but not to the zone of mechanical damage. Therefore, our model can help to understand the differences in wound healing during the early phase of regeneration after thermomechanical vs. mechanical damage. Furthermore, this model lends itself to study the response of other cells, thus broadening the range of thermal injuries that can be analysed. 相似文献
25.
A case study for late Archean and Proterozoic biogeochemical iron‐ and sulphur cycling in a modern habitat—the Arvadi Spring 下载免费PDF全文
Elif Koeksoy Maximilian Halama Nikolas Hagemann Pascal R. Weigold Katja Laufer Sara Kleindienst James M. Byrne Anneli Sundman Kurt Hanselmann Itay Halevy Ronny Schoenberg Kurt O. Konhauser Andreas Kappler 《Geobiology》2018,16(4):353-368
As a consequence of Earth's surface oxygenation, ocean geochemistry changed from ferruginous (iron(II)‐rich) into more complex ferro‐euxinic (iron(II)‐sulphide‐rich) conditions during the Paleoproterozoic. This transition must have had profound implications for the Proterozoic microbial community that existed within the ocean water and bottom sediment; in particular, iron‐oxidizing bacteria likely had to compete with emerging sulphur‐metabolizers. However, the nature of their coexistence and interaction remains speculative. Here, we present geochemical and microbiological data from the Arvadi Spring in the eastern Swiss Alps, a modern model habitat for ferro‐euxinic transition zones in late Archean and Proterozoic oceans during high‐oxygen intervals, which enables us to reconstruct the microbial community structure in respective settings for this geological era. The spring water is oxygen‐saturated but still contains relatively elevated concentrations of dissolved iron(II) (17.2 ± 2.8 μM) and sulphide (2.5 ± 0.2 μM) with simultaneously high concentrations of sulphate (8.3 ± 0.04 mM). Solids consisting of quartz, calcite, dolomite and iron(III) oxyhydroxide minerals as well as sulphur‐containing particles, presumably elemental S0, cover the spring sediment. Cultivation‐based most probable number counts revealed microaerophilic iron(II)‐oxidizers and sulphide‐oxidizers to represent the largest fraction of iron‐ and sulphur‐metabolizers in the spring, coexisting with less abundant iron(III)‐reducers, sulphate‐reducers and phototrophic and nitrate‐reducing iron(II)‐oxidizers. 16S rRNA gene 454 pyrosequencing showed sulphide‐oxidizing Thiothrix species to be the dominating genus, supporting the results from our cultivation‐based assessment. Collectively, our results suggest that anaerobic and microaerophilic iron‐ and sulphur‐metabolizers could have coexisted in oxygenated ferro‐sulphidic transition zones of late Archean and Proterozoic oceans, where they would have sustained continuous cycling of iron and sulphur compounds. 相似文献
26.
Filaković P Koić O Laufer D Radanović-Grgurić L Degmecić D Pozgain I 《Collegium antropologicum》2007,31(4):1105-1109
Differences in the glucose metabolism were examined and analysed in this study between patients treated with olanzapine and risperidone in comparison with healthy volunteers. The aim of the study was to determine differences of the impaired glucose metabolism in the study groups as well as to point out to the possible mechanisms which bring to these differences. To the group of 15 schizophrenic patients treated with olanzapine, and group of 15 schizophrenic patients treated with risperidone and to 14 healthy volunteers oral glucose tolerancy test is applied in order to determine the level of the impaired glucose tolerance. In the group of the patients treated with olanzapine glucose tolerance was impaired in 33% of the patients, while in the group of the patients treated with risperidone in 20%. Impaired glucose tolerance mostly manifested as hyperinsulinemia. Authors discussed about possible mechanisms responsible for the impaired glucose tolerance in the patients treated with new antipsychotics. Authors conclude that insulin resistance is the main mechanism for development of the diabetes type II in the schizophrenic patients treated with antipsychotics. Insulin resistance is the result of the multiple effects of the antipsychotics, among which most common are: increased body mass and direct involvement of the antipsychotics in the glucose metabolism. 相似文献
27.
Fronza M Murillo R Ślusarczyk S Adams M Hamburger M Heinzmann B Laufer S Merfort I 《Bioorganic & medicinal chemistry》2011,19(16):4876-4881
Phytochemical investigations of the n-hexane extract from the roots of Peltodon longipes (Lamiaceae) resulted in the isolation of 12 known abietane diterpenes (1-12). Structures were established on the basis of one and two dimensional nuclear magnetic resonance spectroscopic data ((1)H and (13)C, COSY, HSQC and HMBC), electron ionization mass spectrometric analysis (EIMS) as well as comparison with data from literature. These compounds, as well as eight known diterpenes (13-19) from Salvia miltiorrhiza, and two from Salvia sahendica (20 and 21) were evaluated for their cytotoxic effects in human pancreatic (MIAPaCa-2) and melanoma (MV-3) tumor cell lines using the MTT assay. Tanshinone IIa (13), 7α-acetoxyroyleanone (1), 1,2-dihydrotanshinone (16) and cryptotanshinone (14) had the highest cytotoxic effects in MIAPaCa-2, displaying IC(50) of 1.9, 4.7, 5.6, and 5.8 μM, respectively. Structure-activity relationships of abietane diterpenoid quinones are discussed. 相似文献
28.
Evelin Ramóna Péli Nie Lei Tamás Pócs Zsanett Laufer Stefan Porembski Zoltán Tuba 《Central European Journal of Biology》2011,6(5):838-849
In our present studies, the recovery of photosynthetic activity after rehydration was demonstrated. We measured chlorophyll
fluorescence, CO2 gas exchange and the pigment composition in the previously long-term air-dried cryptogamic inselberg crusts collected from
two tropical areas. The cryptobiotic crusts were collected from different localities on similar ecological and climatic conditions
from extreme habitats of inselbergs (outcrops). These inselbergs are characterized by a dry microclimate and are covered by
scarce soil. We found that the ecophysiological responses of both cryptogamic inselberg crusts showed an extremely high degree
of desiccation-tolerance due to the fast and full recovery during rehydration. The photosynthetic activity of the cryptobiotic
crusts were restored and regained within 15 and 40 min, respectively, after rehydration. Photosynthetic activity of the crusts
was retained at all applied light intensities when enough water was available, however the degree of the recovery was different
between the crusts. Photosynthetic pigment contents were strongly and positively correlated with water content. Our results
indicated that tropical desiccation-tolerant cryptogamic crusts found on inselberg rock surfaces have CO2 fixation ability in the range of cyanobacteria and lichens, suggesting that at a global scale they can assimilate CO2 in a significant amount. 相似文献
29.
Gloria Omosa-Manyonyi Juliet Mpendo Eugene Ruzagira William Kilembe Elwyn Chomba Fran?ois Roman Patricia Bourguignon Marguerite Koutsoukos Alix Collard Gerald Voss Dagna Laufer Gwynn Stevens Peter Hayes Lorna Clark Emmanuel Cormier Len Dally Burc Barin Jim Ackland Kristen Syvertsen Devika Zachariah Kamaal Anas Eddy Sayeed Angela Lombardo Jill Gilmour Josephine Cox Patricia Fast Frances Priddy 《PloS one》2015,10(5)
Background
Sequential prime-boost or co-administration of HIV vaccine candidates based on an adjuvanted clade B p24, RT, Nef, p17 fusion protein (F4/AS01) plus a non-replicating adenovirus 35 expressing clade A Gag, RT, Int and Nef (Ad35-GRIN) may lead to a unique immune profile, inducing both strong T-cell and antibody responses.Methods
In a phase 1, double-blind, placebo-controlled trial, 146 healthy adult volunteers were randomized to one of four regimens: heterologous prime-boost with two doses of F4/AS01E or F4/AS01B followed by Ad35-GRIN; Ad35-GRIN followed by two doses of F4/AS01B; or three co-administrations of Ad35-GRIN and F4/AS01B. T cell and antibody responses were measured.Results
The vaccines were generally well-tolerated, and did not cause serious adverse events. The response rate, by IFN-γ ELISPOT, was greater when Ad35-GRIN was the priming vaccine and in the co-administration groups. F4/AS01 induced CD4+ T-cells expressing primarily CD40L and IL2 +/- TNF-α, while Ad35-GRIN induced predominantly CD8+ T-cells expressing IFN-γ +/- IL2 or TNF-α. Viral inhibition was induced after Ad35-GRIN vaccination, regardless of the regimen. Strong F4-specific antibody responses were induced. Immune responses persisted at least a year after the last vaccination. The complementary response profiles, characteristic of each vaccine, were both expressed after co-administration.Conclusion
Co-administration of an adjuvanted protein and an adenovirus vector showed an acceptable safety and reactogenicity profile and resulted in strong, multifunctional and complementary HIV-specific immune responses.Trial Registration
ClinicalTrials.gov NCT01264445 相似文献30.
Pelletier JP Boileau C Boily M Brunet J Mineau F Geng C Reboul P Laufer S Lajeunesse D Martel-Pelletier J 《Arthritis research & therapy》2005,7(5):R1091-R1102
This study sought to evaluate the levels of mRNA expression and protein synthesis of MMP-13, cathepsin K, aggrecanase-1 (ADAMTS-4),
aggrecanase-2 (ADAMTS-5) and 5-lipoxygenase (5-LOX) in cartilage in the experimental anterior cruciate ligament (ACL) dog
model of osteoarthritis (OA), and to examine the effects of treatment with licofelone, a 5-lipoxygenase (LOX)/cyclooxygenase
(COX) inhibitor, on the levels of these catabolic factors. Sectioning of the ACL of the right knee was performed in three
experimental groups: group 1 received no active treatment (placebo group); and groups 2 and 3 received therapeutic concentrations
of licofelone (2.5 or 5.0 mg/kg/day orally, respectively) for 8 weeks, beginning the day following surgery. A fourth group
consisted of untreated dogs that were used as normal controls. Specimens of cartilage were selected from lesional areas of
OA femoral condyles and tibial plateaus, and were processed for real-time quantitative PCR and immunohistochemical analyses.
The levels of MMP-13, cathepsin K, ADAMTS-4, ADAMTS-5 and 5-LOX were found to be significantly increased in OA cartilage.
Licofelone treatment decreased the levels of both mRNA expression and protein synthesis of the factors studied. Of note was
the marked reduction in the level of 5-LOX gene expression. The effects of the drug were about the same at both tested dosages.
In vivo treatment with therapeutic dosages of licofelone has been found to reduce the degradation of OA cartilage in experimental
OA. This, coupled with the results of the present study, indicates that the effects of licofelone are mediated by the inhibition
of the major cartilage catabolic pathways involved in the destruction of cartilage matrix macromolecules. Moreover, our findings
also indicate the possible auto-regulation of 5-LOX gene expression by licofelone in OA cartilage. 相似文献