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371.
Veronica Schmitz Rhana Berto da Silva Prata Mayara Garcia de Mattos Barbosa Mayara Abud Mendes Sheila Santos Brand?o Thaís Porto Amadeu Luciana Silva Rodrigues Helen Ferreira Fabrício da Mota Ramalho Costa Jessica Brand?o dos Santos Fabiana dos Santos Pacheco Alice de Miranda Machado José Augusto da Costa Nery Mariana de Andrea Hacker Anna Maria Sales Roberta Olmo Pinheiro Euzenir Nunes Sarno 《PLoS neglected tropical diseases》2016,10(8)
Erythema Nodosum Leprosum (ENL) is an immune reaction in leprosy that aggravates the patient´s clinical condition. ENL presents systemic symptoms of an acute infectious syndrome with high leukocytosis and intense malaise clinically similar to sepsis. The treatment of ENL patients requires immunosuppression and thus needs to be early and efficient to prevent both disabilities and permanent nerve damage. Some patients experience multiple episodes of ENL and prolonged use of immunosuppressive drugs may lead to serious adverse effects. Thalidomide treatment is extremely effective at ameliorating ENL symptoms. Several mechanisms have been proposed to explain the efficacy of thalidomide in ENL, including the inhibition of TNF production. Given its teratogenicity, thalidomide is prohibitive for women of childbearing age. A rational search for molecular targets during ENL episodes is essential to better understand the disease mechanisms involved, which may also lead to the discovery of new drugs and diagnostic tests. Previous studies have demonstrated that IFN-γ and GM-CSF, involved in the induction of CD64 expression, increase during ENL. The aim of the present study was to investigate CD64 expression during ENL and whether thalidomide treatment modulated its expression. Leprosy patients were allocated to one of five groups: (1) Lepromatous leprosy, (2) Borderline leprosy, (3) Reversal reaction, (4) ENL, and (5) ENL 7 days after thalidomide treatment. The present study demonstrated that CD64 mRNA and protein were expressed in ENL lesions and that thalidomide treatment reduced CD64 expression and neutrophil infiltrates—a hallmark of ENL. We also showed that ENL blood neutrophils exclusively expressed CD64 on the cell surface and that thalidomide diminished overall expression. Patient classification based on clinical symptoms found that severe ENL presented high levels of neutrophil CD64. Collectively, these data revealed that ENL neutrophils express CD64, presumably contributing to the immunopathogenesis of the disease. 相似文献
372.
Sayuri Sales Rodrigo Portes Ureshino Renato Tavares dos Santos Pereira Milene Schmidt Amaral Luna Marcelo Pires de Oliveira Norma Yamanouye Rosely Oliveira Godinho Soraya Soubhi Smaili Catarina Segreti Porto Fernando Maurício Francis Abdalla 《Life sciences》2010,86(21-22):832-838
AimsThe aim of the present study was to investigate the effects of different periods of ovariectomy and 17β-estradiol replacement on apoptotic cell death and expression of members of the Bcl-2 family in the rat hippocampus.Main methodsHippocampi were obtained from rats in proestrus, ovariectomized (15 days, 21 days and 36 days), ovariectomized for 15 days and then treated with 17β-estradiol for 7 or 21 days, and rats ovariectomized and immediately treated with 17β-estradiol for 21 days.The expression of Bcl-2 and Bax and the number of apoptotic cells were determined.Key findingsOvariectomy decreased Bcl-2 expression and increased Bax expression and the number of apoptotic cells. Replacement with 17β-estradiol (21 days) throughout the post-ovariectomy period reduced the number of apoptotic cells to the control levels, and prevented the effects of ovariectomy on Bax expression, but only partially restored the Bcl-2 expression. After 15 days of ovariectomy, the replacement with 17β-estradiol for 21 days, but not for 7 days, restored the Bcl-2 and Bax expression and the percentage of apoptotic cells to the levels found in the proestrus control.SignificanceThe present results show that a physiological concentration of 17β-estradiol may help maintain long-term neuronal viability by regulating the expression of members of the Bcl-2 family. Even after a period of hormonal deprivation, treatment with 17β-estradiol is able to restore the expression of Bax and Bcl-2 to control levels, but the duration of the treatment is a key factor to obtain the desired effect. These data provide new understanding into the mechanisms contributing to the neuroprotective action of estrogen. 相似文献
373.
Teresa Nazareth Carla Alexandra Sousa Gra?a Porto Luzia Gon?alves Gon?alo Seixas Luís Antunes Ana Clara Silva Rosa Teodósio 《PLoS neglected tropical diseases》2015,9(3)
The ability to effectively modify behaviours is increasingly relevant to attain
and maintain a good health status. Current behaviour-change models and theories
present two main approaches for (healthier) decision-making: one
analytical/logical, and one experiential/emotional/intuitive. Therefore, to
achieve an integral and dynamic understanding of the public perceptions both
approaches should be considered: community surveys should measure cognitive
understanding of health-risk contexts, and also explore how past experiences
affect this understanding. In 2011, community perceptions regarding domestic
source reduction were assessed in Madeira Island. After Madeira’s
first dengue outbreak (2012) a unique opportunity to compare perceptions before
and after the outbreak-experience occurred. This was the aim of this study,
which constituted the first report on the effect of an outbreak experience on
community perceptions regarding a specific vector-borne disease. A
cross-sectional survey was performed within female residents at the most
aegypti-infested areas. Perceptions regarding domestic
source reduction were assessed according to the Essential Perception
(EP)-analysis tool. A matching process paired individuals from studies performed
before and after the outbreak, ensuring homogeneity in six determinant
variables. After the outbreak, there were more female residents who assimilated
the concepts considered to be essential to understand the proposed behaviour.
Nevertheless, no significant difference was observed in the number of female
residents who achieved the defined ‘minimal
understanding’’. Moreover, most of the population (95.5%) still
believed at least in one of the identified myths. After the outbreak some myths
disappeared and others appeared. The present study quantified and explored how
the experience of an outbreak influenced the perception regarding a
dengue-preventive behaviour. The outbreak experience surprisingly led to the
appearance of new myths within the population, apart from the expected increase
of relevant concepts’ assimilation. Monitoring public perceptions is
therefore crucial to make preventing dengue campaigns updated and worthy. 相似文献
374.
Moura RS Ferreira TS Lopes AA Pires KM Nesi RT Resende AC Souza PJ Silva AJ Borges RM Porto LC Valenca SS 《Phytomedicine》2012,19(3-4):262-269
Short term inhalation of cigarette smoke (CS) induces significant lung inflammation due to an imbalance of oxidant/antioxidant mechanisms. A?ai fruit (Euterpe oleracea) has significant antioxidant and anti-inflammatory actions. The present study aimed to determine whether oral administration of an a?ai stone extract (ASE) could reduce lung inflammation induced by CS. Thirty C57BL/6 mice were assigned to three groups (n=10 each): the Control+A group was exposed to ambient air and treated orally with ASE 300 mg/kg/day; the CS group was exposed to smoke from 6 cigarettes per day for 5 days; and the CS+A group was exposed to smoke from 6 cigarettes per day for 5 days and treated orally with ASE (300 mg/kg/day). On day 6, all mice were sacrificed. After bronchoalveolar lavage, the lungs were removed for histological and biochemical analyses. The CS group exhibited increases in alveolar macrophage (AMs) and neutrophil numbers (PMNs), myeloperoxidase (MPO), superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase activities (GPx), TNF-α expression, and nitrites levels in lung tissue when compared with the control ones (p<0.001 for all parameters). The AMs, PMNs, MPO, SOD, CAT, GPx and nitrite were significantly reduced by oral administration of ASE when compared with CS group (p<0.001 for all parameters, with exception of AMs p<0.01). The present results suggested that systemic administration of an ASE extract could reduce the inflammatory and oxidant actions of CS. Thus, the results of this study in mice should stimulate future studies on ASE as a potential agent to protect against CS-induced inflammation in humans. 相似文献
375.
An exception to the generally conservative nature of plastid gene evolution
is the gene coding for the beta" subunit of RNA polymerase, rpoC2. Previous
work by others has shown that maize and rice have an insertion in the
coding region of rpoC2, relative to spinach and tobacco. To assess the
distribution of this extra coding sequence, we surveyed a broad
phylogenetic sample comprising 55 species from 17 angiosperm families by
using Southern hybridization. The extra coding sequence is restricted to
the grasses (Poaceae). DNA sequence analysis of 11 species from all five
subfamilies within the grass family demonstrates that the extra sequence in
the coding region of rpoC2 is a repetitive array that exhibits more than a
twofold increase in nucleotide substitution, as well as a large number of
insertion/deletion events, relative to the adjacent flanking sequences. The
structure of the array suggests that slipped-strand mispairing causes the
repeated motifs and adds to the mechanisms through which the coding
sequence of plastid genes are known to evolve. Phylogenetic analyses based
on the sequence data from grass species support several relationships
previously suggested by morphological work, but they are ambiguous about
broad relationships within the family.
相似文献
376.
377.
We have attempted to elucidate the natural history of pulmonary aspergillus intracavitary colonization (PAIC) based on more than 350 cases of the disease observed in the last 11 years and on data collected from the literature. The data indicate that PAIC is a dynamic process consequent to the continual growth and death of fungal elements and also with their relationships to the anatomic features of the cavity (valvular mechanisms, vascular alteration). The clinical presentations reflect immunological changes in the host. Metabolites produced by the species of Aspergillus involved affect the clinical presentation of the syndrome. 相似文献
378.
Six cases of pulmonary paracoccidioidomycosis diagnosed only by transthoracic fine needle aspiration are presented. The clinical
and radiological presentation is varied. The most frequent use of this technique will permit the diagnosis of early lesions
of mycosis.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
379.
Nucleotide sequence analysis of the human salivary protein genes HIS1 and HIS2, and evolution of the STATH/HIS gene family 总被引:1,自引:0,他引:1
Human histatins are a family of low-M(r), neutral to very basic,
histidine-rich salivary polypeptides. They probably function as part of the
nonimmune host defense system in the oral cavity. A 39-kb region of DNA
containing the HIS1 and HIS2 genes was isolated from two human genomic
phage libraries as a series of overlapping clones. The nucleotide sequences
of the HIS1 gene and part of the HIS2(1) gene were determined. The
transcribed region of HIS1 spans 8.5 kb and contains six exons and five
introns. The HIS1 and HIS2(1) genes exhibit 89% overall sequence identity,
with exon sequences exhibiting 95% identity. The two loci probably arose by
a gene duplication event approximately 15-30 Mya. The HIS1 sequence data
were also compared with that of STATH. Human statherin is a low-M(r) acidic
phosphoprotein that acts as an inhibitor of precipitation of calcium
phosphate salts in the oral cavity. The HIS1 and STATH genes show nearly
identical overall gene structures. The HIS1 and STATH loci exhibit 77%-81%
sequence identity in intron DNA and 80%-88% sequence identity in noncoding
exons but only 38%-43% sequence identity in the protein-coding regions of
exons 4 and 5. These unusual data suggest that HIS1, HIS2, and STATH belong
to a single gene family exhibiting accelerated evolution between the HIS
and STATH coding sequences.
相似文献
380.
Two experiments were carried out to observe the effect of the application of an anticholinesterasic agent on water and food intake in rats. The first studied the effect of fenitrothion injected into the L.H.A. on water and food intake. An increase in water intake was observed in the 6th hour, while food intake decreased in the first and 24th hours. The same study was performed in the V.M.N. In this case, only an alteration in food intake occurred, with a decrease in the first hour, followed by an increase in the other two periods. These results suggest a cholinergic interaction between these two structures in the regulation of water and food intake, and also a central action of cholinesterasic agents when applied systemically. 相似文献