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101.
T. Y. C. Massuda L. A. Nagashima P. C. Leonello M. S. Kaminami M. S. Mantovani A. Sano J. Uno E. J. Venancio Z. P. Camargo E. N. Itano 《Mycopathologia》2011,171(3):161-169
Paracoccidioidomycosis (PCM) is a systemic mycosis caused by the fungus Paracoccidioides brasiliensis (Pb). The cyclosporin A (CsA) is an immunosuppressant drug that inhibits calcineurin and has been described as a potential
antifungal drug. The present study investigated the effect of CsA on the immune response, fungal load/antigenemia in experimental
murine PCM. It was used four groups of BALB/c mice: (a) infected with 1 × 105 Pb18 yeast cells (Pb), (b) infected and treated with CsA every other day 10 mg/kg of CsA (s.c.) during 30 days (Pb/CsA),
(c) treated with CsA (CsA) and (d) no infected/treated (PBS). The immune response was evaluated by lymphocyte proliferation,
DTH assays to exoAgs, ELISA for IgG anti-gp43 (specific immune responses) and cytokine serum levels (IFN-γ, TNF-α, IL-4 and
IL-10). Fungal load was determined by lung colony-forming units (CFU) counts, lung and liver histopathology analysis and antigenemia
determined by inhibition-ELISA. As expected, CsA was able to inhibit the specific cellular and humoral immune response (P < 0.05), with decrease in serum IFN-γ, TNF-α and IL-4 levels (P < 0.05). Cyclosporin A treatment also resulted in significantly decreased lung Pb CFU (P < 0.05) as well as a lower number of yeasts in the lung and liver (P < 0.05) by histopathology. In concordance, the decreased antigenemia was observed in Pb/CsA group (P < 0.05). In conclusion, even with immunosuppressive action, treatment with CsA results in decreased lung fungal load/antigenemia
in experimental PCM in BALB/c mice. Further study is required to determine whether this represents less severe disease or
protection by CsA. 相似文献
102.
Letícia B. Rocha Anna R. R. Santos Danielle D. Munhoz Lucas T. A. Cardoso Daniela E. Luz Fernanda B. Andrade Denise S. P. Q. Horton Waldir P. Elias Roxane M. F. Piazza 《PLoS neglected tropical diseases》2014,8(9)
Background
Enteropathogenic and enterohemorrhagic Escherichia coli (EPEC/EHEC) are human intestinal pathogens responsible for diarrhea in both developing and industrialized countries. In research laboratories, EPEC and EHEC are defined on the basis of their pathogenic features; nevertheless, their identification in routine laboratories is expensive and laborious. Therefore, the aim of the present work was to develop a rapid and simple assay for EPEC/EHEC detection. Accordingly, the EPEC/EHEC-secreted proteins EspA and EspB were chosen as target antigens.Methodology
First, we investigated the ideal conditions for EspA/EspB production/secretion by ELISA in a collection of EPEC/EHEC strains after cultivating bacterial isolates in Dulbecco’s modified Eagle’s medium (DMEM) or DMEM containing 1% tryptone or HEp-2 cells-preconditioned DMEM, employing either anti-EspA/anti-EspB polyclonal or monoclonal antibodies developed and characterized herein. Subsequently, a rapid agglutination latex test (RALT) was developed and tested with the same collection of bacterial isolates.Principal findings
EspB was defined as a biomarker and its corresponding monoclonal antibody as the tool for EPEC/EHEC diagnosis; the production of EspB was better in DMEM medium. RALT assay has the sensitivity and specificity required for high-impact diagnosis of neglected diseases in the developing world.Conclusion
RALT assay described herein can be considered an alternative assay for diarrhea diagnosis in low-income countries since it achieved 97% sensitivity, 98% specificity and 97% efficiency. 相似文献103.
Gap-phase regeneration in a tropical montane forest: the effects of gap structure and bamboo species 总被引:11,自引:0,他引:11
To study the influence of gap structure and bamboo species on the regrowth of montane Atlantic forest, colonization by plants was characterized in 30 treefall gaps (30.3–500.5 m2). The study was conducted at Santa Virgínia (45°30 W, 23°17 S), a 4970-ha reserve of Atlantic montane forest in southeastern Brazil. Area covered by bamboos ranged from 0% to 100% of gap area. Average height of surrounding canopies ranged from 12 to 30 m. As gap are covered by bamboo and average height of surrounding canopies increased, both density and richness of pioneer woody species decreased. Density and richness of shade-tolerant species were negatively influenced by gap area. Low-light-demanding species of Miconia, Leandra and Rapanea accounted for the majority of both pioneer species and individuals sampled, whereas high-light demanding pioneers of Cecropia, Alchornea and Tibouchina were poorly represented. We suggest that in the Atlantic montane forest bamboo species compete for gaps, excluding other light-demanding pioneers. This results in an overall reduction of pioneer species richness in the Atlantic forest. 相似文献
104.
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106.
Silvia Garbelli Stefania Mantovani Belinda Palermo Claudia Giachino 《Pigment cell & melanoma research》2005,18(4):234-242
Vitiligo is a relatively common progressive depigmentary condition that is believed to be due to the autoimmune‐mediated loss of epidermal melanocytes. An interesting aspect of vitiligo is its relation to melanoma: cytotoxic T lymphocytes directed to self‐antigens shared by normal melanocytes and melanoma cells are found in both conditions and might prove important in melanocyte destruction, yet the resulting immune reactions are completely different. From this standpoint, the selective destruction of pigment cells that occurs in cases of vitiligo is the therapeutic goal sought in melanoma research. In the present article, we will address these issues by reviewing current literature on the subject as well as by posing some speculations. 相似文献
107.
Filipa Abreu Antonio Souto Daniela M. O. Bonci Viviani Mantovani Daniel M. A. Pessoa Nicola Schiel 《American journal of primatology》2019,81(3)
Most species of New World primates have an unusual color vision pattern that can affect an individual's ability to detect food. Whereas males can only be dichromatic, females can be either dichromatic or trichromatic. Trichromats are expected to have an advantage in detecting conspicuous food whereas dichromats should be better at locating cryptic resources. Here we aimed to understand how color vision phenotype influences insect foraging by five groups of common marmosets living in a semiarid environment. We recorded insect predation events, noting morphotype and color of the captured insect, and the substrate from which it was captured. Color modeling suggested that, for all values of chromatic contrast resulting from comparing the measured insect–substrate pairs, trichromats outperformed dichromats. Females showed an overall higher insect capture rate than males. Females also showed a higher capture rate of conspicuous insects but there was no sex difference for the capture of cryptic insects. When we compared only dichromatic individuals there was no difference between sexes. These findings suggest that differences found in capture rate related not only to sex but also to visual polymorphism and that the latter is a crucial factor determining insect capture rate in common marmosets. Nevertheless, these results should be interpreted with caution because of the small number (three) of dichromat females and the unknown phenotype of the remaining females. Our results support the balancing selection hypothesis, suggesting that the advantage of one phenotype over the other may depend on environmental circumstances. This hypothesis has recently been considered as the most plausible for the maintenance of visual polymorphism in New World primates. 相似文献
108.
A Punturieri A Santoni W J Ming N Nobili A Mantovani B Bottazzi 《Cellular immunology》1989,123(2):257-263
Rat peripheral blood large granular lymphocytes (LGL) were isolated by fractionation on discontinuous Percoll gradients. LGL migration was studied using nitrocellulose filters. Rat LGLs migrated into nitrocellulose filters in response to N-formyl-methionyl-leucyl-phenylalanine (f-MLP), casein, and serum components. Percoll-enriched high-density lymphocytes had small, but significant, migratory capacity in response to stimuli under these conditions. Removal of OX-19+ contaminating cells by panning confirmed the migratory capability of rat LGL/NK cells under these conditions. Checkerboard analysis of the LGL response to chemoattractants revealed that induction of migration involved chemokinesis although a chemotactic component was also discernible. The prompt migration of rat LGL in response to different stimuli is consistent with the hypothesis that these cells may represent one of the first easily mobilizable lines of resistance against noxious agents. In the rat combined in vitro/in vivo studies may provide a better understanding of the regulation of LGL recruitment and extravasation. 相似文献
109.
Cytotoxicity of activated monocytes on endothelial cells 总被引:4,自引:0,他引:4
G Peri F Chiaffarino S Bernasconi I M Padura A Mantovani 《Journal of immunology (Baltimore, Md. : 1950)》1990,144(4):1444-1448
Unstimulated human monocytes did not express appreciable levels of cytotoxicity on normal human umbilical vein endothelial cells (EC) in a 24-48 hr TdR release assay. On activation with IFN-gamma and LPS, monocytes had appreciable cytotoxicity on EC. Monocyte cytotoxicity on EC was not dependent on the presence of contaminating lymphoid cells. Recombinant TNF, IL-1, and IL-6 as well as monocyte supernatants did not exert a cytotoxic effect on EC. Moreover, anti-TNF, anti-IL-1, and anti-IL-6 antibodies, as well as scavengers of reactive oxygen intermediates, did not affect the cytotoxicity of activated monocytes on EC. Antibodies against the beta-chain (CD18) of leukocyte integrins inhibited the adhesion and cytotoxicity of activated monocytes on EC. Pretreatment of EC with IL-1 augmented the adhesion of monocytes on EC. Normal monocytes were not cytotoxic on IL-1-pretreated EC and IL-1 treatment did not increase the susceptibility of EC to activated monocytes. Thus adhesion is necessary but not sufficient for monocyte killing of EC. Anti-alpha L (LFA-1) antibodies markedly reduced monocyte cytotoxicity on EC, although anti-alpha X (p150) antibodies had only a modest effect. Anti-alpha M (Mac-1/CR3) antibodies were intermediate inhibitors of EC killing by activated monocytes. Thus, alpha L, beta 2 (LFA-1), and, to a lesser extent, alpha M, beta 2 (Mac-1/CR3) and alpha X, beta 2 (p 150, 95) integrins are the main adhesive structures involved in the cytotoxic interaction of activated monocytes with EC. Monocyte-mediated damage of EC could play a role as a mechanism of tissue injury under conditions of local or systemic activation of mononuclear phagocytes. 相似文献
110.