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101.
102.
Jakub Kreisinger Géraldine Bastien Heidi C Hauffe Julian Marchesi Sarah E Perkins 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2015,370(1675)
The gut microbiota is vital to host health and, as such, it is important to elucidate the mechanisms altering its composition and diversity. Intestinal helminths are host immunomodulators and have evolved both temporally and spatially in close association with the gut microbiota, resulting in potential mechanistic interplay. Host–helminth and host–microbiota interactions are comparatively well-examined, unlike microbiota–helminth relationships, which typically focus on experimental infection with a single helminth species in laboratory animals. Here, in addition to a review of the literature on helminth–microbiota interactions, we examined empirically the association between microbiota diversity and composition and natural infection of multiple helminth species in wild mice (Apodemus flavicollis), using 16S rRNA gene catalogues (metataxonomics). In general, helminth presence is linked with high microbiota diversity, which may confer health benefits to the host. Within our wild rodent system variation in the composition and abundance of gut microbial taxa associated with helminths was specific to each helminth species and occurred both up- and downstream of a given helminth''s niche (gut position). The most pronounced helminth–microbiota association was between the presence of tapeworms in the small intestine and increased S24–7 (Bacteroidetes) family in the stomach. Helminths clearly have the potential to alter gut homeostasis. Free-living rodents with a diverse helminth community offer a useful model system that enables both correlative (this study) and manipulative inference to elucidate helminth–microbiota interactions. 相似文献
103.
Jana Hurnakova Jakub Zavada Petra Hanova Hana Hulejova Martin Klein Herman Mann Olga Sleglova Marta Olejarova Sarka Forejtova Olga Ruzickova Martin Komarc Jiri Vencovsky Karel Pavelka Ladislav Senolt 《Arthritis research & therapy》2015,17(1)
IntroductionCalprotectin, a heterodimeric complex of S100A8/9 (MRP8/14), has been proposed as an important serum biomarker that reflects disease activity and structural joint damage in rheumatoid arthritis (RA). The objective of this cross-sectional study was to test the hypothesis that calprotectin is associated with clinical and ultrasound-determined disease activity in patients with RA.MethodsA total of 37 patients with RA (including 24 females, a mean disease duration of 20 months) underwent a clinical examination and 7-joint ultrasound score (German US-7) of the clinically dominant hand and foot to assess synovitis by grey-scale (GS) and synovial vascularity by power Doppler (PD) ultrasound using semiquantitative 0–3 grading. The levels of serum calprotectin and C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) were determined at the time of the ultrasound assessment. We analysed the relationship between serum calprotectin level, traditional inflammatory markers, and ultrasound-determined synovitis.ResultsThe levels of serum calprotectin were significantly correlated with swollen joint count (r = 0.465, p < 0.005), DAS28-ESR (r = 0.430, p < 0.01), ESR (r = 0.370, p < 0.05) and, in particular, CRP (r = 0.629, p < 0.001). Calprotectin was significantly associated with GS (r = 0.359, p < 0.05) and PD synovitis scores (r = 0.497, p < 0.005). Using multivariate regression analysis, calprotectin, adjusted for age and sex, was a better predictor of PD synovitis score (R2 = 0.765, p < 0.001) than CRP (R2 = 0.496, p < 0.001).ConclusionsThe serum levels of calprotectin are significantly associated with clinical, laboratory and ultrasound assessments of RA disease activity. These results suggest that calprotectin might be superior to CRP for monitoring ultrasound-determined synovial inflammation in RA patients. 相似文献
104.
Anna K. Kiss Agnieszka BazylkoAgnieszka Filipek Sebastian GranicaEdyta Jaszewska Urszula KiarszysAnita Ko?mider Jakub Piwowarski 《Phytomedicine》2011,18(7):557-560
Willow herb tea or preparation are available and relatively popular in the European market, and claimed to be effective inter alia because of their anti-inflammatory activity. The present study is therefore aimed at comparing the anti-inflammatory and antioxidant activity of extracts of the three most popular Epilobium species (E. angustifolium, E. hirsutum and E. parviflorum) and at juxtaposing this activity against the dominating compounds from the following extracts: oenothein B (OeB), quercetin-3-O-glucuronide and myricetin-3-O-rhamnoside. The phytochemical analysis of the extracts has shown that OeB quantities vary between 20% and 35%, while flavonoids content does not exceed 2%. All extracts have inhibited the activity of hyaluronidase and lipoxygenase with IC50 around 5 μg/ml and 25 μg/ml. The inhibition of hyaluronidase is related with the presence of OeB, a strong inhibitor of this enzyme (IC50 1.1 μM). Additionally, the extracts inhibited myeloperoxidase (MPO) release from stimulated neutrophils. OeB inhibited MPO release similarly to the anti-inflammatory drug indomethacin with IC50 7.7 μM and 15.4 μM, respectively. Tested extracts significantly reduced the production of reactive oxygen species (ROS) from f-MLP and PMA induced neutrophils with IC50 5 μg/ml and 25 μg/ml, respectively. The flavonoids content seems to exert little influence on extracts’ activity, contrary to OeB, whose high concentration explains the activity of extract obtained from Epilobium. Tested currently marketed Epilobium preparations are often wrongly assigned, but we should stress that the level of OeB in all tested herbs was high and always exceeded 2% in raw material. 相似文献
105.
Jaroslav Červinka Martin Šálek Petr Pavluvčík Jakub Kreisinger 《Biodiversity and Conservation》2011,20(14):3459-3475
The marked negative impact of habitat fragmentation and the edge effect on many populations of bird species is a recent major
concern in conservation biology. Here, we focus on the edge effect in different sized forest patches in Central European farmland. In particular, we tested
whether the distribution of mammalian mesopredators is related to fragment size and distance to habitat edge, and whether
the contribution of these factors is additive or interactive. To assess fine-scale utilization of forest edges, we established
transects of four scent stations at different distances from forest edges into the interior (0, 25, 50, 100 m) in 146 forest
fragments of variable patch size (3.2–5099.6 ha) from May to June, 2008–2009. This large sample size allowed us to perform
detailed analyses separately for all detected species. Our findings confirm that mammalian mesopredators strongly prefer habitat
edges and small forest fragments. The probability of occurrence tended to decrease with increasing distance from the edge
for all seven carnivore species detected. The carnivores’ occurrence was also negatively correlated with forest fragment area.
All detected species tended to prefer small fragments, with the exception of the Eurasian badger (showing the reverse but
non-significant pattern) and the red fox (no effect of fragment size). In addition, the non-significant interaction between
fragment size and distance to edge suggests that both of these factors contribute independently and additively to mesopredator-mediated
effects on biota in a fragmented landscape. 相似文献
106.
The structural chirality is an inherent feature of fully synthetic boron cluster compounds that sometimes exhibit unique biochemical effects. HPLC studies with zwitter-ionic cluster boron compounds and electrophoretic studies with boron cluster anions reveal that the chiral separability of these species is remarkably dissimilar to that of organic species, if uncharged cyclodextrins are used as chiral selectors. Furthermore, marked differences were found between the analytical characteristics of the chiral separations of the boron cluster species and those of the organic species with uncharged cyclodextrins. The present-day experimental database indicates that the rules valid for the chiral separations of the organic species cannot be applied to the chiral separations of the boron cluster species without experimental verification. The current extent of research work devoted to the investigation of chirality and chiral separations of boron cluster species is negligibly small in comparison with that devoted to the investigation of chirality and chiral separations of organic species. This makes difficult a reliable explanation of both the particularities observed in chiral separations of boron cluster species with cyclodextrins as chiral selectors and the strange effects related to these separations at the moment. 相似文献
107.
108.
Saldarriaga JF Gile GH James ER Horák A Scheffrahn RH Keeling PJ 《The Journal of eukaryotic microbiology》2011,58(6):487-496
Pseudotrichonympha is a large hypermastigote parabasalian found in the hindgut of several species of rhinotermitid termites. The genus was discovered more than 100 years ago, and although over a dozen species have since been described, this represents only a small fraction of its likely diversity: the termite genera from which Pseudotrichonympha is known are all species rich, and in most cases their hindgut symbionts have not been examined. Even formally described species are mostly lacking in detailed microscopic data and/or sequence data. Using small subunit ribosomal RNA gene sequences and light and scanning electron microscopy we describe here the morphology and molecular phylogenetic position of two Pseudotrichonympha species: the type species for the genus, Pseudotrichonympha hertwigi from Coptotermes testaceus (described previously in line drawing only), and Pseudotrichonympha paulistana from Heterotermes tenuis (described previously based on light microscopy only). 相似文献
109.
110.
The mitotic checkpoint functions to ensure accurate chromosome segregation by regulating the progression from metaphase to anaphase. Once the checkpoint has been satisfied, it is inactivated in order to allow the cell to proceed into anaphase and complete the cell cycle. The minus end-directed microtubule motor dynein/dynactin has been implicated in the silencing of the mitotic checkpoint by "stripping" checkpoint proteins off kinetochores. A recent study suggested that Nordihydroguaiaretic acid (NDGA) stimulates dynein/dynactin-mediated transport of its cargo including ZW10 (Zeste White 10). We analyzed the effects of NDGA on dynein/dynactin dependent transport of the RZZ (Zeste White 10, Roughdeal, Zwilch) complex as well as other kinetochore components from kinetochores to spindle poles. Through this approach we have catalogued several kinetochore and centromere components as dynein/dynactin cargo. These include hZW10, hZwilch, hROD, hSpindly, hMad1, hMad2, hCENP-E, hCdc27, cyclin-B and hMps1. Furthermore, we found that treatment with NDGA induced a robust accumulation and complete stabilization of hZW10 at spindle poles. This finding suggests that NDGA may not induce dynein/dynactin transport but rather interfere with cargo release. Lastly, we determined that NDGA induced accumulation of checkpoint proteins at the poles requires dynein/dynactin-mediated transport, hZW10 kinetochore localization and kinetochore-microtubule attachments but not tension or Aurora B kinase activity. 相似文献