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141.
Clara Correia‐Melo Francisco DM Marques Rhys Anderson Graeme Hewitt Rachael Hewitt John Cole Bernadette M Carroll Satomi Miwa Jodie Birch Alina Merz Michael D Rushton Michelle Charles Diana Jurk Stephen WG Tait Rafal Czapiewski Laura Greaves Glyn Nelson Mohammad Bohlooly‐Y Sergio Rodriguez‐Cuenca Antonio Vidal‐Puig Derek Mann Gabriele Saretzki Giovanni Quarato Douglas R Green Peter D Adams Thomas von Zglinicki Viktor I Korolchuk João F Passos 《The EMBO journal》2016,35(7):724-742
142.
Examining variation in the leaf mass per area of dominant species across two contrasting tropical gradients in light of community assembly 下载免费PDF全文
Margot Neyret Lisa Patrick Bentley Imma Oliveras Beatriz S. Marimon Ben Hur Marimon‐Junior Edmar Almeida de Oliveira Fábio Barbosa Passos Rosa Castro Ccoscco Josias dos Santos Simone Matias Reis Paulo S. Morandi Gloria Rayme Paucar Arturo Robles Cáceres Yolvi Valdez Tejeira Yovana Yllanes Choque Norma Salinas Alexander Shenkin Gregory P. Asner Sandra Díaz Brian J. Enquist Yadvinder Malhi 《Ecology and evolution》2016,6(16):5674-5689
Understanding variation in key functional traits across gradients in high diversity systems and the ecology of community changes along gradients in these systems is crucial in light of conservation and climate change. We examined inter‐ and intraspecific variation in leaf mass per area (LMA) of sun and shade leaves along a 3330‐m elevation gradient in Peru, and in sun leaves across a forest–savanna vegetation gradient in Brazil. We also compared LMA variance ratios (T‐statistics metrics) to null models to explore internal (i.e., abiotic) and environmental filtering on community structure along the gradients. Community‐weighted LMA increased with decreasing forest cover in Brazil, likely due to increased light availability and water stress, and increased with elevation in Peru, consistent with the leaf economic spectrum strategy expected in colder, less productive environments. A very high species turnover was observed along both environmental gradients, and consequently, the first source of variation in LMA was species turnover. Variation in LMA at the genus or family levels was greater in Peru than in Brazil. Using dominant trees to examine possible filters on community assembly, we found that in Brazil, internal filtering was strongest in the forest, while environmental filtering was observed in the dry savanna. In Peru, internal filtering was observed along 80% of the gradient, perhaps due to variation in taxa or interspecific competition. Environmental filtering was observed at cloud zone edges and in lowlands, possibly due to water and nutrient availability, respectively. These results related to variation in LMA indicate that biodiversity in species rich tropical assemblages may be structured by differential niche‐based processes. In the future, specific mechanisms generating these patterns of variation in leaf functional traits across tropical environmental gradients should be explored. 相似文献
143.
Alzira Kelly Passos Roriz Hilton F. Japyassú Iara Sordi Joachim-Bravo 《Journal of Insect Behavior》2018,31(5):535-551
Ritualized courtship behaviors are used to recognize potential mates and behavioral patterns are inevitably different among populations that demonstrate reproductive incompatibility. We characterized and compared the courtship behaviors of two morphotypes of the cryptic species complex Anastrepha fraterculus: Brazil-1 morphotype and Brazil-3 morphotype. Courtship behaviors were filmed to analyze the behavioral sequences of these two morphotypes during homotypic crossings. The behavioral units Alignment (AL) and Abdominal movements (AB and AB-call) were newly recognized in the courtship ethogram of Anastrepha fraterculus males. The two morphotypes show distinct behavioral sequences leading up to copulation. Some behaviors were repeated frequently during the courtship process, while others were more restricted to the final moments of courtship. The three behavioral units that contributed most to copulation success were Contact, Alignment, and Arrowhead 1 in the Brazil-1 morphotype and Alignment, Arrowhead 1, and Fanning in the Brazil-3 morphotype. Some behavioral routines differed across the two morphotypes. Significant differences were also noted between the frequencies of the behavioral units displayed during courtship in the two morphotypes. The relationships between the pre-zygotic incompatibilities of the Brazil-1 and Brazil-3 morphotypes and the differences between the courtship behaviors of their males are discussed. Our results indicate that behavioral isolation is involved in the process of pre-zygotic reproductive isolation of Brazil-1 and Brazil-3 morphotypes. 相似文献
144.
145.
A. B. Araújo J. M. Furlan G. D. Salton T. Schmalfuss L. M. Röhsig L. M. R. Silla E. P. Passos A. H. Paz 《Biotechnology letters》2018,40(6):989-998
Objective
To compare four enzymatic protocols for mesenchymal stem cells (MSCs) isolation from amniotic (A-MSC) and chorionic (C-MSC) membranes, umbilical cord (UC-MSC) and placental decidua (D-MSC) in order to define a robust, practical and low-cost protocol for each tissue.Results
A-MSCs and UC-MSCs could be isolated from all samples using trypsin/collagenase-based protocols; C-MSCs could be isolated from all samples with collagenase- and trypsin/collagenase-based protocols; D-MSCs were isolated from all samples exclusively with a collagenase-based protocol.Conclusions
The trypsin-only protocol was least efficient; the collagenase-only protocol was best for C-MSCs and D-MSCs; the combination of trypsin and collagenase was best for UC-MSCs and none of tested protocols was adequate for A-MSCs isolation.146.
Natália Schneider Fabiany da Costa Gon?alves Fernanda Otesbelgue Pinto Patrícia Luciana da Costa Lopez Anelise Bergmann Araújo Bianca Pfaffenseller Eduardo Pandolfi Passos Elizabeth Obino Cirne-Lima Luíse Meurer Marcelo Lazzaron Lamers Ana Helena Paz 《PloS one》2015,10(3)
Glucocorticoids and immunosuppressive drugs are commonly used to treat inflammatory disorders, such as inflammatory bowel disease (IBD), and despite a few improvements, the remission of IBD is still difficult to maintain. Due to their immunomodulatory properties, mesenchymal stem cells (MSCs) have emerged as regulators of the immune response, and their viability and activation of their migratory properties are essential for successful cell therapy. However, little is known about the effects of immunosuppressant drugs used in IBD treatment on MSC behavior. The aim of this study was to evaluate MSC viability, nuclear morphometry, cell polarity, F-actin and focal adhesion kinase (FAK) distribution, and cell migratory properties in the presence of the immunosuppressive drugs azathioprine (AZA) and dexamethasone (DEX). After an initial characterization, MSCs were treated with DEX (10 μM) or AZA (1 μM) for 24 hrs or 7 days. Neither drug had an effect on cell viability or nuclear morphometry. However, AZA treatment induced a more elongated cell shape, while DEX was associated with a more rounded cell shape (P < 0.05) with a higher presence of ventral actin stress fibers (P < 0.05) and a decrease in protrusion stability. After 7 days of treatment, AZA improved the cell spatial trajectory (ST) and increased the migration speed (24.35%, P < 0.05, n = 4), while DEX impaired ST and migration speed after 24 hrs and 7 days of treatment (-28.69% and -25.37%, respectively; P < 0.05, n = 4). In conclusion, our data suggest that these immunosuppressive drugs each affect MSC morphology and migratory capacity differently, possibly impacting the success of cell therapy. 相似文献
147.
Espanhol Aline R. Cardoso Renato S. Junta Cristina M. Victorero Geneviève Loriod Béatrice Nguyen Catherine Passos Geraldo A.S. 《Molecular and cellular biochemistry》2004,260(1):65-68
The CBA/J inbred mouse strain constitutes an interesting in vivo model-system for studies on molecular genetics of thymus ontogeny. Using RT-PCR method we have found previously that several immune system related genes as interleukins and MHC are differentially expressed. During this period the onset of T-cell receptor beta rearrangements also occur. To know which other genes are modulated during the ontogeny of the thymus, the mRNA expression levels of fetal thymus (15 and 16 days gestation) of CBA/J mouse strain were measured by hybridization with a set of four macroarrays containing a panel of 6,144 IMAGE cDNA clones from MTB thymus library. We found 145 differentially expressed sequences; 44 were up- and 101 down-regulated in the thymus at 15–16 days gestation. Among these sequences, only 20 are identified as genes whose functions are known and 125 are still unknown. Our data demonstrated that, despite intense research on maturation of the immune system focusing on the activity of several well-characterized genes, the large scale expression profile during thymus ontogeny is still an open matter. The use of cDNA-array technology is an affordable method to identify new genes that may play a role in this phenomenon. 相似文献
148.
Marina Loyola Dantas Juliana Menezes Gomes Cabral de Oliveira Lucas Carvalho Sara Timóteo Passos Adriano Queiroz Luiz Henrique Guimar?es Paulo Machado Edgar Carvalho Sérgio Arruda 《Memórias do Instituto Oswaldo Cruz》2014,109(2):202-209
Cutaneous leishmaniasis (CL) is the most frequent clinical form of tegumentary
leishmaniasis and is characterised by a single or a few ulcerated skin lesions that
may disseminate into multiple ulcers and papules, which characterise disseminated
leishmaniasis (DL). In this study, cells were quantified using immunohistochemistry
and haematoxylin and eosin staining (CD4+, CD68+, CD20+, plasma cells and
neutrophils) and histopathology was used to determine the level of inflammation in
biopsies from patients with early CL, late CL and DL (ulcers and papules). The
histopathology showed differences in the epidermis between the papules and ulcers
from DL. An analysis of the cells present in the tissues showed similarities between
the ulcers from localised CL (LCL) and DL. The papules had fewer CD4+ T cells than
the DL ulcers. Although both CD4+ cells and macrophages contribute to inflammation in
early CL, macrophages are the primary cell type associated with inflammation
intensity in late ulcers. The higher frequency of CD20+ cells and plasma cells in
lesions demonstrates the importance of B cells in the pathogenesis of leishmaniasis.
The number of neutrophils was the same in all of the analysed groups. A comparison
between the ulcers from LCL and DL and the early ulcers and papules shows that few
differences between these two clinical forms can be distinguished by observing only
the tissue. 相似文献
149.
Tatiana Alves Rigamonte Fernandes Wendel Batista da Silveira Flávia Maria Lopes Passos Tiago Domingues Zucchi 《Antonie van Leeuwenhoek》2014,106(2):391-398
Although many putative laccase-like genes have been assigned to members of the phylum Actinobacteria, few of the related enzymes have been characterized so far. It is noteworthy, however, that this small number of enzymes has presented properties with industrial relevance. This observation, combined with the recognized biotechnological potential and the capability of this phylum to degrade recalcitrant soil polymers, has attracted attention for bioprospective approaches. In the present work, we have designed and tested primers that were specific for detection of sub-groups of laccase-like genes within actinomycetes, which corresponded to the superfamilies I and K from the classification presented by the laccase and multicopper oxidase engineering database. The designed primers have amplified laccase-like gene fragments from actinomycete isolates that were undetectable by primers available from the literature. Furthermore, phylogenetic alignments suggest that some of these fragments may belong to new laccases-like proteins, and thus emphasize the benefits of designing subgroup-specific primers. 相似文献
150.
Passos MC da Fonte Ramos C Potente Dutra SC Gaspar de Moura E 《The Journal of nutritional biochemistry》2001,12(5):300-303
Iodine supply is important to avoid neonatal hypothyroidism. This study evaluated whether protein restriction during lactation affects iodine transfer to the pups through the milk. We studied lactating rats fed an 8% protein-restricted diet (PR), a control 23% protein diet (C), and an energy-restricted diet group (ER). On days 4, 12 and 21, mothers were separated from their pups for 4 h, injected with (131)I IP, and put together with their pups. The animals were killed 2 h later. PR pups had a significant decrease in iodine uptake in the gastric content and duodenal mucosa on the 4th day. On the contrary, at 12 and 21 days radioiodine was increased in the gastric content and in the duodenal mucosa. ER pups had an increase in iodine uptake in the gastric content and in the duodenal mucosa only at the end of lactation. The thyroid iodine uptake in PR pups was significantly decreased on the 4th day and significantly increased on the 21st day compared to control. When injected IP with an equivalent amount of (131)I, the PR pups had a decrease in thyroid iodine uptake on the 4th and 12th day, while ER pups had no significant changes. So, these data suggest that protein restriction during lactation was associated with lower iodine secretion into the milk in the beginning of lactation. However, at the end of lactation, an adaptation process seems to occur leading to a higher transfer of iodine through the milk that compensates the impairment of thyroid iodine uptake in these pups. 相似文献