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991.
Neutrophil migration in inflammation: nitric oxide inhibits rolling, adhesion and induces apoptosis. 总被引:3,自引:0,他引:3
Daniela Dal Secco Juliane Alves Paron Sandra H P de Oliveira Sérgio Henrique Ferreira Jo?o Santana Silva Fernando de Queiroz Cunha 《Nitric oxide》2003,9(3):153-164
There is controversy in the literature over whether nitric oxide (NO) released during the inflammatory process has a pro- or inhibitory effect on neutrophil migration. The aim of the present investigation was to clarify this situation. Treatment of rats with non-selective, NG-nitro-L-arginine (nitro), or selective inducible NO synthase (iNOS), aminoguanidine (amino) inhibitors enhanced neutrophil migration 6h after the administration of low, but not high, doses of carrageenan (Cg) or Escherichia coli endotoxin (LPS). The neutrophil migration induced by N-formyl-methionyl-leucyl-phenylalanine (fMLP) was also enhanced by nitro or amino treatments. The enhancement of Cg-induced neutrophil migration by NOS inhibitor treatments was reversed by co-treatment with L-arginine, suggesting an involvement of the L-arginine/NOS pathway in the process. The administration of Cg in iNOS deficient (iNOS(-/-)) mice also enhanced the neutrophil migration compared with wild type mice. This enhancement was markedly potentiated by treatment of iNOS(-/-) mice with nitro. Investigating the mechanisms by which NOS inhibitors enhanced the neutrophil migration, it was observed that they promoted an increase in Cg-induced rolling and adhesion of leukocytes to endothelium and blocked the apoptosis of emigrated neutrophils. Similar results were observed in iNOS(-/-) mice, in which these mechanisms were potentiated and reverted by nitro and L-arginine treatments, respectively. In conclusion, these results suggest that during inflammation, NO released by either constitutive NOS (cNOS) or iNOS down-modulates the neutrophil migration. This NO effect seems to be a consequence of decreased rolling and adhesion of the neutrophils on endothelium and also the induction of apoptosis in migrated neutrophils. 相似文献
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Pietro K. Maruyama Amanda F. Cunha Everton Tizo-Pedroso Kleber Del-Claro 《Journal of Ethology》2010,28(2):339-344
Behavioural patterns of birds commonly vary according to flock size and daily activity pattern. Southern lapwing behaviours
and their relation with flock size were studied, as well as the relationship between the frequency of behaviours and the period
of the day. Results showed that the proportion of time spent in foraging and vigilance was higher during the morning, when
small groups were more common, and decreased from midday on, when group size increased. Maintenance and inactivity (sleeping)
behaviours presented the opposite pattern. Correlation between flock size and period of the day, and their similar effects
on bird behaviour may be evidence that groups of different sizes could have different functions throughout the day. Our results
show that southern lapwings seem to form smaller flocks for feeding in the beginning of the day and larger flocks later for
different activities (e.g., maintenance and sleeping). In this sense, it is possible that group size variation throughout
the day is related to different demands for specific behaviours (functions) of groups, according to the daily activity patterns
of the birds. 相似文献
996.
José L. Martín Pedro Cardoso Manuel Arechavaleta Paulo A. V. Borges Bernardo F. Faria Cristina Abreu António F. Aguiar José A. Carvalho Ana C. Costa Regina T. Cunha Francisco M. Fernandes Rosalina Gabriel Roberto Jardim Carlos Lobo António M. F. Martins Paulo Oliveira Pedro Rodrigues Luís Silva Dinarte Teixeira Isabel R. Amorim Nídia Homem Berta Martins Mónica Martins Enésima Mendonça 《Biodiversity and Conservation》2010,19(6):1659-1682
Oceanic islands have been the grand stage of documented extinctions. In view of limited resources, efficient prioritization is crucial to avoid the extinction of taxa. This work lists the top 100 management priority species for the European archipelagos of the Macaronesian region (Azores, Madeira and the Canary Islands), taking into account both their protection priority and their management feasibility. Bryophytes, vascular plants, molluscs, arthropods and vertebrates were scored by species experts following two sets of criteria: (i) protection priority, including ecological value, singularity, public institutions’ management responsibilities and social value; (ii) management feasibility, including threats knowledge and control feasibility, external socio-economical support for management and biological recovery potential. Environmental managers weighted the same criteria according to their management importance. Final species scores were determined by the combination of both species valuation and criteria weighting. Vascular plants dominate the Top 100 list, followed by arthropods and vertebrates. The majority of listed taxa are endemic to one archipelago or even to a single island. The management feasibility criteria did not dictate that all taxa must be eminently endangered, as for most of the species it should be relatively easy to control threats. The main advantages of this process are the independent participation of scientists and conservation managers, the inclusion of criteria on both protection priority and management feasibility and the taxonomically unbiased nature of the process. This study provides a potentially useful biodiversity conservation tool for the Macaronesian archipelagos that could be readily implemented by the respective regional governments in future legislation. 相似文献
997.
Juliana J.H. Celestino Jamily B. Bruno Isabel B. Lima‐Verde Maria Helena T. Matos Mércia Viviane A. Saraiva Roberta N. Chaves Fabricio S. Martins Anderson P. Almeida Rodrigo M.S. Cunha Laritza F. Lima Khesller P.O. Name Claudio C. Campello José Roberto V. Silva Sônia N. Báo José Ricardo Figueiredo 《Molecular reproduction and development》2010,77(3):231-240
The aims of this study were to investigate steady‐state level of Kit Ligand (KL) mRNA and its effects on in vitro survival and growth of caprine preantral follicles. RT‐PCR was used to analyze caprine steady‐state level of KL mRNA in primordial, primary, and secondary follicles, and in small (1–3 mm) and large (3–6 mm) antral follicles. Furthermore, ovarian fragments were cultured for 1 or 7 days in Minimal Essential Medium (MEM+) supplemented with KL (0, 1, 10, 50, 100, or 200 ng/ml). Noncultured (control) and cultured fragments were processed for histology and transmission electron microscopy (TEM). RT‐PCR demonstrated an increase in steady‐state level of KL mRNA during the transition from primary to secondary follicles. Small antral follicles had higher steady‐state levels of KL mRNA in granulosa and theca cells than large follicles. After 7 days, only 50 ng/ml of KL had maintained the percentage of normal follicles similar to control. After 1 day, all KL concentrations reduced the percentage of primordial follicles and increased the percentage of growing follicles. KL at 10, 50, 100, or 200 ng/ml increased primary follicles, compared to MEM+ after 7 days. An increase in oocyte and follicular diameter was observed at 50 ng/ml of KL. TEM confirmed ultrastructural integrity of follicles after 7 days at 50 ng/ml of KL. In conclusion, the KL mRNAs were detected in all follicular categories. Furthermore, 50 ng/ml of KL maintained the integrity of caprine preantral follicle cultured for 7 days and stimulated primordial follicle activation and follicle growth. Mol. Reprod. Dev. 77: 231–240, 2010. © 2009 Wiley‐Liss, Inc. 相似文献
998.
Ricardo Cardoso Neves Marina Ribeiro da Cunha Peter Funch Andreas Wanninger Reinhardt Møbjerg Kristensen 《Helgoland Marine Research》2010,64(3):257-262
Cycliophora is a recently described phylum to which only two species have been assigned so far, Symbion pandora and S. americanus. The cycliophoran life cycle is complex and alternates between asexual and sexual stages. Although not recognized as an entirely
independent free-swimming stage when the phylum was first described, the dwarf male has a remarkably complex bodyplan albeit
its very small size (approx. 30–40 μm in length). Aiming to increase the knowledge on the gross morphology of the cycliophoran
dwarf male, specimens from S. pandora and S. americanus were analyzed by scanning electron microscopy. In both species, anterior and ventral ciliated fields, as well as paired lateral
sensorial organs, were identified, thus confirming previous observations. However, new details are described herein such as
the penial pouch that encloses the penis. We compare our findings on both Symbion species with the data currently available on other metazoan dwarf males. 相似文献
999.
Mauricio L Barreto Sergio S Cunha Rosemeire Fiaccone Renata Esquivel Leila D Amorim Sheila Alvim Matildes Prado Alvaro A Cruz Philip J Cooper Darci N Santos Agostino Strina Neuza Alcantara-Neves Laura C Rodrigues 《Respiratory research》2010,11(1):167
Background
The causation of asthma is poorly understood. Risk factors for atopic and non-atopic asthma may be different. This study aimed to analyze the associations between markers of poverty, dirt and infections and wheezing in atopic and non-atopic children.Methods
1445 children were recruited from a population-based cohort in Salvador, Brazil. Wheezing was assessed using the ISAAC questionnaire and atopy defined as allergen-specific IgE ≥0.70 kU/L. Relevant social factors, environmental exposures and serological markers for childhood infections were investigated as risk factors using multivariate multinomial logistic regression.Results
Common risk factors for wheezing in atopic and non-atopic children, respectively, were parental asthma and respiratory infection in early childhood. No other factor was associated with wheezing in atopic children. Factors associated with wheezing in non-atopics were low maternal educational level (OR 1.49, 95% CI 0.98-2.38), low frequency of room cleaning (OR 2.49, 95% CI 1.27-4.90), presence of rodents in the house (OR 1.48, 95% CI 1.06-2.09), and day care attendance (OR 1.52, 95% CI 1.01-2.29).Conclusions
Non-atopic wheezing was associated with risk factors indicative of poverty, dirt and infections. Further research is required to more precisely define the mediating exposures and the mechanisms by which they may cause non-atopic wheeze. 相似文献1000.
Flávia C Rodrigues-Lisoni Paulo PeitlJr Alessandra Vidotto Giovana M Polachini José V Maniglia Juliana Carmona-Raphe Bianca R Cunha Tiago Henrique Caique F Souza Rodrigo AP Teixeira Erica E Fukuyama Pedro MichaluartJr Marcos B de Carvalho Sonia M Oliani Head Neck Genome Project GENCAPO Eloiza H Tajara 《BMC medical genomics》2010,3(1):14