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101.
Paulo De Marco Júnior 《Studies on Neotropical Fauna and Environment》2013,48(3):186-189
During quantitative samples of invertebrate fauna in two lakes in the Rio Doce State Park (Marliéria, MG) I found some individuals of the introduced aquatic snail Melanoides tuberculata. It was most abundant in areas with high human activity, where the original vegetation was removed from the shallow areas near the margin. Population structure inferred by size-class data suggests that the most impacted area was invaded first and that these snails maintain a viable population in Dom Helvécio lake. Potential spread of the snail in this lake system is tentatively related to the characteristics of the bank vegetation and I presume that the not yet invaded Carioca lake has better conditions for an exponential growth of this species. 相似文献
102.
Paulo De Sa Peixoto Guillaume Laurent Thierry Aza?s Gervaise Mosser 《The Journal of biological chemistry》2013,288(11):7528-7535
In vivo, collagen I, the major structural protein in human body, is found assembled into fibrils. In the present work, we study a high concentrated collagen sample in its soluble, fibrillar, and denatured states using one and two dimensional {1H}-13C solid-state NMR spectroscopy. We interpret 13C chemical shift variations in terms of dihedral angle conformation changes. Our data show that fibrillogenesis increases the side chain and backbone structural complexity. Nevertheless, only three to five rotameric equilibria are found for each amino acid residue, indicating a relatively low structural heterogeneity of collagen upon fibrillogenesis. Using side chain statistical data, we calculate equilibrium constants for a great number of amino acid residues. Moreover, based on a 13C quantitative spectrum, we estimate the percentage of residues implicated in each equilibrium. Our data indicate that fibril formation greatly affects hydroxyproline and proline prolyl pucker ring conformation. Finally, we discuss the implication of these structural data and propose a model in which the attractive force of fibrillogenesis comes from a structural reorganization of 10 to 15% of the amino acids. These results allow us to further understand the self-assembling process and fibrillar structure of collagen. 相似文献
103.
Nicolás O. Amiano María J. Costa R. Macarena Reiteri Cristian Payés Diego Guerrieri Nancy L. Tateosian Mercedes L. Sánchez Paulo C. Maffia Miriam Diament Romina Karas Andrés Orqueda Miguel Rizzo Laura Alaniz Guillermo Mazzolini Slobodanka Klein Jean‐Michel Sallenave H. Eduardo Chuluyan 《Journal of cellular physiology》2013,228(2):469-475
Secretory leukocyte protease inhibitor (SLPI) is a serine protease inhibitor that was related to cancer development and metastasis dissemination on several types of tumors. However, it is not known the effect of SLPI on mammary and colon tumors. The aim of this study was to examine the effect of SLPI on mammary and colon tumor growth. The effect of SLPI was tested on in vitro cell apoptosis and in vivo tumor growth experiments. SLPI over‐expressing human and murine mammary and colon tumor cells were generated by gene transfection. The administration of murine mammary tumor cells over‐expressing high levels of SLPI did not develop tumors in mice. On the contrary, the administration of murine colon tumor cells over‐expressing SLPI, developed faster tumors than control cells. Intratumoral, but not intraperitoneal administration of SLPI, delayed the growth of tumors and increased the survival of mammary but not colon tumor bearing mice. In vitro culture of mammary tumor cell lines treated with SLPI, and SLPI producer clones were more prone to apoptosis than control cells, mainly under serum deprivation culture conditions. Herein we demonstrated that SLPI induces the apoptosis of mammary tumor cells in vitro and decreases the mammary but not colon tumor growth in vivo. Therefore, SLPI may be a new potential therapeutic tool for certain tumors, such as mammary tumors. J. Cell. Physiol. 228: 469–475, 2013. © 2012 Wiley Periodicals, Inc. 相似文献
104.
Sohee Baek Nam Joo Kang Grzegorz M. Popowicz Marcelino Arciniega Sung Keun Jung Sanguine Byun Nu Ry Song Yong-Seok Heo Bo Yeon Kim Hyong Joo Lee Tad A. Holak Martin Augustin Ann M. Bode Robert Huber Zigang Dong Ki Won Lee 《Journal of molecular biology》2013,425(2):411-423
c-Jun NH2-terminal kinases (JNKs) and phosphatidylinositol 3-kinase (PI3-K) play critical roles in chronic diseases such as cancer, type II diabetes, and obesity. We describe here the binding of quercetagetin (3,3′,4′,5,6,7-hydroxyflavone), related flavonoids, and SP600125 to JNK1 and PI3-K by ATP-competitive and immobilized metal ion affinity-based fluorescence polarization assays and measure the effect of quercetagetin on JNK1 and PI3-K activities. Quercetagetin attenuated the phosphorylation of c-Jun and AKT, suppressed AP-1 and NF-κB promoter activities, and also reduced cell transformation. It attenuated tumor incidence and reduced tumor volumes in a two-stage skin carcinogenesis mouse model.Our crystallographic structure determination data show that quercetagetin binds to the ATP-binding site of JNK1. Notably, the interaction between Lys55, Asp169, and Glu73 of JNK1 and the catechol moiety of quercetagetin reorients the N-terminal lobe of JNK1, thereby improving compatibility of the ligand with its binding site. The results of a theoretical docking study suggest a binding mode of PI3-K with the hydroxyl groups of the catechol moiety forming hydrogen bonds with the side chains of Asp964 and Asp841 in the p110γ catalytic subunit. These interactions could contribute to the high inhibitory activity of quercetagetin against PI3-K. Our study suggests the potential use of quercetagetin in the prevention or therapy of cancer and other chronic diseases. 相似文献
105.
Catarina Prado e Castro José Paulo Sousa María Isabel Arnaldos João Gaspar María Dolores García 《法国昆虫学会纪事》2013,49(1-2):128-139
The first forensic entomological study performed in Portugal is presented. Two piglet (Sus scrofa L.) carcasses were used to determine adult Calliphoridae activity on carrion over a period of 121 days, all along the end of spring and the summer, both in a shaded and a sunny site. Five decomposition stages were observed and a total of 10723 adult Calliphoridae, belonging to 11 species, were collected. Calliphora vicina, Calliphora vomitoria, Chrysomya albiceps and Lucilia caesar were the dominant species in this study. Decomposition was faster on the carcass exposed to the sun and the number of Calliphoridae specimens was higher there than in the shaded site. It was found a significant effect of the decomposition stage in the number of specimens attracted to the carcass, as well as a significant effect of the interaction between the decomposition stage and insolation regime. Calliphora and Lucilia species did not show preference for sunny or shaded areas. Important differences in the Calliphoridae community structure were found compared to other regions of the Iberian Peninsula, reinforcing the need of further studies in different environments and regions of this geographical area in order to collect information about the local necrophagous fauna used in forensic practice. 相似文献
106.
Marcos Paulo Wille Thaís Guimar?es Guilherme Henrique Campos Furtado Arnaldo Lopes Colombo 《Memórias do Instituto Oswaldo Cruz》2013,108(3):288-292
Candida species are an important cause of bloodstream infections (BSI). To evaluate the epidemiological, clinical and microbiological aspects of two cohorts {1994-1999 [period 1 (P1) ]; 2000-2004 [period 2 (P2) ]} of candidaemic patients, we performed a retrospective analysis from a laboratory-based survey. A total of 388 candidaemias were identified, with an incidence of 0.20/1,000 patient-days and a significant increase in P2 vs. P1 (0.25 vs. 0.15, p = 0.04). Cancer and prior antibiotic use were frequent and Candida albicans was the most prevalent species found (42.4%). Resistance to fluconazole was found in 2.47% of the strains. No differences were observed in the species distribution of Candida during the study periods. In the P2 cohort, there were higher prevalence of elderly individuals, cardiac, pulmonary and liver diseases, renal failure, central venous catheters and antibiotic therapy. In P1, there were higher prevalence of neurological diseases and chemotherapy. The crude mortality was 55.4%. In conclusion, our incidence rates remained high. Furthermore, the distribution pattern of Candida species and the fluconazole resistance profile remained unchanged. Moreover, we found a clear trend of higher prevalence of candidaemia among the elderly and among patients with comorbidities. Finally, it is necessary to discuss strategies for the prevention and control of Candida BSI in Brazil. 相似文献
107.
Cleoni Alves Mendes de Lima Harrison Magdinier Gomes Maraníbia Aparecida Cardoso Oelemann Jesus Pais Ramos Paulo Cezar Caldas Carlos Eduardo Dias Campos Márcia Aparecida da Silva Pereira Fátima Fandinho Onofre Montes Maria do Socorro Calixto de Oliveira Philip Noel Suffys Maria Manuela da Fonseca Moura 《Memórias do Instituto Oswaldo Cruz》2013,108(4):457-462
The main cause of pulmonary tuberculosis (TB) is infection with
Mycobacterium tuberculosis (MTB). We aimed to evaluate the
contribution of nontuberculous mycobacteria (NTM) to pulmonary disease in
patients from the state of Rondônia using respiratory samples and
epidemiological data from TB cases. Mycobacterium isolates were identified using
a combination of conventional tests, polymerase chain reaction-based restriction
enzyme analysis of hsp65 gene and hsp65 gene
sequencing. Among the 1,812 cases suspected of having pulmonary TB, 444 yielded
bacterial cultures, including 369 cases positive for MTB and 75 cases positive
for NTM. Within the latter group, 14 species were identified as
Mycobacterium abscessus, Mycobacterium
avium, Mycobacterium fortuitum,
Mycobacterium intracellulare, Mycobacterium
gilvum, Mycobacterium gordonae,
Mycobacterium asiaticum, Mycobacterium
tusciae, Mycobacterium porcinum,
Mycobacterium novocastrense, Mycobacterium
simiae, Mycobacterium szulgai,
Mycobacterium phlei and Mycobacterium
holsaticum and 13 isolates could not be identified at the species
level. The majority of NTM cases were observed in Porto Velho and the relative
frequency of NTM compared with MTB was highest in Ji-Paraná. In approximately
half of the TB subjects with NTM, a second sample containing NTM was obtained,
confirming this as the disease-causing agent. The most frequently observed NTM
species were M. abscessus and M. avium and
because the former species is resistant to many antibiotics and displays
unsatisfactory cure rates, the implementation of rapid identification of
mycobacterium species is of considerable importance. 相似文献
108.
109.
Francisco Morinha Paulo Travassos Fernanda Seixas Ana Martins Rita Bastos Diogo Carvalho 《Bird Study》2013,60(2):255-259
Capsule The Skylark Alauda arvensis had the highest overall mortality in ten Northern Portuguese wind farms surveyed between 2006 and 2011. Analysis from the integration of conventional and molecular techniques suggest a sex and age biased mortality affecting mainly adult males (90.9%), which may be related to their characteristic breeding male song-flights making them highly vulnerable to collision with wind turbines. The results highlight the added value of more complete population impact assessments that go beyond simple carcass identification at wind farms. 相似文献
110.
Antimicrobial, cytolytic, and cell-penetrating peptides induce pores or perturbations in phospholipid membranes that result in fluxes of dyes into or out of lipid vesicles. Here we examine the fluxes induced by four of these membrane-active peptides in giant unilamellar vesicles. The type of flux is determined from the modality of the distributions of vesicles as a function of their dye content using the statistical Hartigan dip test. Graded and all-or-none fluxes correspond to unimodal and bimodal distributions, respectively. To understand how these distributions arise, we perform Monte Carlo simulations of peptide-induced dye flux into vesicles using a very simple model. The modality of the distributions depends on the rate constants of pore opening and closing, and dye flux. If the rate constants of pore opening and closing are both much smaller than that of dye flux through the pore, all-or-none influx occurs. However, if one of them, especially the rate constant for pore opening, increases significantly relative to the flux rate constant, the process becomes graded. In the experiments, we find that the flux type is the same in giant and large vesicles, for all peptides except one. But this one exception indicates that the flux type cannot be used to unambiguously predict the mechanism of membrane permeabilization by the peptides. 相似文献