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81.
doi:10.1111/j.1741‐2358.2009.00319.x
Exfoliative cytology of the oral mucosa in burning mouth syndrome: a cytomorphological and cytomorphometric analysis Objective: The aim of this study was to evaluate oral epithelial cells by exfoliative cytology in burning mouth syndrome (BMS). Material and methods: Oral smears were collected from clinically normal‐appearing mucosa by liquid‐based exfoliative cytology in 40 individuals (20 BMS patients and 20 healthy controls matched for age and gender) and analysed for cytological and cytomorphometric techniques. Results: Mean values of nuclear area (NA) for experimental and control groups were, respectively, 67.52 and 55.64 μm2 (p < 0.05). Cytoplasmic area (CA) showed the following mean values: 1258.0 (experimental) and 2069.0 μm2 (control). Nucleus‐to‐cytoplasm area ratio for the experimental group was 0.07, besides the control group was 0.03 (p < 0.05). Morphologically, oral smears exhibited normal epithelial cells in both experimental and control groups. There was a significant predominance of nucleated cells of the superficial layer in the smears of BMS patients (p = 0.00001). Conclusion: This study revealed that oral mucosa of BMS patients exhibited significant cytomorphometric changes in the oral epithelial cells. These changes probably are associated with epithelial atrophy and a deregulated maturation process that may contribute to the oral symptoms of pain and discomfort in BMS.  相似文献   
82.
β-1,3-glucanases are found in organisms as diverse as plants, animals, bacteria and fungi. In plants, such enzymes are not only associated with defense mechanisms against pathogens, but also play critical roles in physiological and developmental processes. Here we identified a new β-1,3-glucanase in maize seeds, and named it ZmGlucA. Sequence analysis revealed that ZmGlucA belongs to the class A of β-1,3-glucanase, a class related to defense and physiological processes in plants. mRNA and protein assays showed that zmGlucA is expressed exclusively in seeds, and it is differentially regulated during seed development. Additionally, zmGlucA expression is strongly induced in seeds of the mutant dek 827Kpro1, which is defective for embryo and endosperm development. Our data support the idea that ZmGlucA protein is relevant to seed development.  相似文献   
83.
Norovirus (NoV) infections are a major cause of acute gastroenteritis outbreaks around the world. In Brazil, the surveillance system for acute diarrhoea does not include the diagnosis of NoV, precluding the ability to assess its impact on public health. The present study assessed the circulation of NoV genotypes in different Brazilian states by partial nucleotide sequencing analysis of the genomic region coding for the major capsid viral protein. NoV genogroup II genotype 4 (GII.4) was the prevalent (78%) followed by GII.6, GII.7, GII.12, GII.16 and GII.17, demonstrating the great diversity of NoV genotypes circulating in Brazil. Thus, this paper highlights the importance of a virological surveillance system to detect and characterize emerging strains of NoV and their spreading potential.  相似文献   
84.
85.
The loss of CD4(+) T cells and the impairment of CD8(+) T cell function in HIV infection suggest that pharmacological treatment with IL-7 and IL-15, cytokines that increase the homeostatic proliferation of T cells and improve effector function, may be beneficial. However, these cytokines could also have a detrimental effect in HIV-1-infected individuals, because both cytokines increase HIV replication in vitro. We assessed the impact of IL-7 and IL-15 treatment on viral replication and the immunogenicity of live poxvirus vaccines in SIV(mac251)-infected macaques (Macaca mulatta). Neither cytokine augmented the frequency of vaccine-expanded CD4(+) or CD8(+) memory T cells, clonal recruitment to the SIV-specific CD8(+) T cell pool, or CD8(+) T cell function. Vaccination alone transiently decreased the viral set point following antiretroviral therapy suspension. IL-15 induced massive proliferation of CD4(+) effector T cells and abrogated the ability of vaccination to decrease set point viremia. In contrast, IL-7 neither augmented nor decreased the vaccine effect and was associated with a decrease in TGF-beta expression. These results underscore the importance of testing immunomodulatory approaches in vivo to assess potential risks and benefits for HIV-1-infected individuals.  相似文献   
86.

Plant galls are generated by the stimuli of gall-inducing organisms on their hosts, creating gall morphotypes that vary in color, shape, size, and tissue organization. Herein, we propose to compare the structural features of gall morphotypes on the superhost Croton floribundus (Euphorbiaceae) in order to recognize gall morphospecies, i.e., galls with similar shapes but different internal structures. Non-galled leaves and galls were analyzed macroscopically, histologically, and histochemically for the detection of primary metabolites, and the results obtained were used for statistical analyses of similarity. Among the eight gall morphospecies, four are globoid, two are lenticular, one is fusiform and one is marginal leaf rolling. Stomatal differentiation and the occurrence of different types of trichomes were impaired in some gall morphospecies. Three patterns of organization of the ground system are recognized, ranging from the maintenance of mesophyll cells that differentiate into palisade and spongy cells dorsiventrally to the formation of a complex cortex with three morphofunctional layers. The marginal leaf rolling galls have the simplest anatomical structures, quite similar to those of the non-galled host leaf, while lenticular, globoid (types I to IV), and fusiform galls are anatomically more complex. Herein, we report on eight gall morphospecies occurring on C. floribundus, which are distinguished by morpho-anatomical attributes and show the disruption of the morphogenetic patterns of the host leaf toward the morphogenesis of unique gall features.

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87.
Chagas disease continues to be an important cause of morbidity, mortality and disability in several Latin American countries, including Brazil. Using findings from the Global Burden of Disease Study 2016 (GBD, 2016), we present years of life lost, years lived with disability, and disability-adjusted life years due to Chagas disease in Brazil, by sex, age group, and Brazilian states, from 1990 to 2016. Results are reported in absolute numbers and age-standardized rates (per 100,000 population) with 95% uncertainty intervals. In 2016, 141,640 disability-adjusted life years (95% uncertainty intervals: 129,065–155,941) due to Chagas disease were estimated in Brazil, with a relative reduction of 36.7% compared with 1990 (223,879 disability-adjusted life years (95% uncertainty intervals: 209,372–238,591)). Age-standardized disability-adjusted life year rates declined at the national level (?69.7%) and in all Brazilian states between 1990 and 2016, but with different regional patterns. The decrease in the disability-adjusted life year rates was driven primarily by a consistent reduction in the years of life lost rates, the main component of total disability-adjusted life years for Chagas disease. The highest fatal and non-fatal burden due to Chagas disease was observed among males, the elderly, and in those Brazilian states encompassing important endemic areas for vector transmission in the past. Despite the consistent reduction in its burden during the period, Chagas disease is still an important and neglected cause of health lost due to premature mortality and disability in Brazil. Efforts should be made to maintain the political interest and sustainability of surveillance and control actions for Chagas disease, prevent the risk of re-emergence of vector transmission in endemic areas, and provide health care to chronically infected individuals, including early diagnosis and treatment interventions.  相似文献   
88.
The disposal of reject brine, a highly concentrated waste by-product generated by various industrial processes, represents a major economic and environmental challenge. The common practice in dealing with the large amounts of brine generated is to dispose of it in a pond and allow it to evaporate. The rate of evaporation is therefore a key factor in the effectiveness of the management of these ponds. The addition of various dyes has previously been used as a method to increase the evaporation rate. In this study, a biological approach, using pigmented halophilic bacteria (as opposed to chemical dyes), was assessed. Two bacteria, an Arthrobacter sp. and a Planococcus sp. were selected due to their ability to increase the evaporation of synthetic brine. When using industrial brine, supplementation of the brine with an iron source was required to maintain the pigment production. Under these conditions, the Planococcus sp. CP5-4 produced a carotenoid-like pigment, which resulted in a 20% increase in the evaporation rate of the brine. Thus, the pigment production capability of halophilic bacteria could potentially be exploited as an effective step in the management of industrial reject brines, analogous to the crystallizer ponds used to mine salt from sea water.  相似文献   
89.
Leprosy remains prevalent in Brazil. ErbB2 is a receptor for leprosy bacilli entering Schwann cells, which mediates Mycobacterium leprae-induced demyelination and the ERBB2 gene lies within a leprosy susceptibility locus on chromosome 17q11-q21. To determine whether polymorphisms at the ERBB2 locus contribute to this linkage peak, three haplotype tagging single nucleotide polymorphisms (tag-SNPs) (rs2517956, rs2952156, rs1058808) were genotyped in 72 families (208 cases; 372 individuals) from the state of Pará (PA). All three tag-SNPs were associated with leprosy per se [best SNP rs2517959 odds ratio (OR) = 2.22; 95% confidence interval (CI) 1.37-3.59; p = 0.001]. Lepromatous (LL) (OR = 3.25; 95% CI 1.37-7.70; p = 0.007) and tuberculoid (TT) (OR = 1.79; 95% CI 1.04-3.05; p = 0.034) leprosy both contributed to the association, which is consistent with the previous linkage to chromosome 17q11-q21 in the population from PA and supports the functional role of ErbB2 in disease pathogenesis. To attempt to replicate these findings, six SNPs (rs2517955, rs2517956, rs1810132, rs2952156, rs1801200, rs1058808) were genotyped in a population-based sample of 570 leprosy cases and 370 controls from the state of Rio Grande do Norte (RN) and the results were analysed using logistic regression analysis. However, none of the associations were replicated in the RN sample, whether analysed for leprosy per se, LL leprosy, TT leprosy, erythema nodosum leprosum or reversal reaction conditions. The role of polymorphisms at ERBB2 in controlling susceptibility to leprosy in Brazil therefore remains unclear.  相似文献   
90.
Lactobacillus plantarum has been used in human clinical trials to promote beneficial effects in the immune system, to alleviate intestinal disorders, and to reduce the risk of cardiovascular disease. It is also involved in many fermentation processes in the food industry. However, information on the fate of ingested L. plantarum is limited. In this study, 61 subjects received daily doses of fermented milk containing 2 × 1011 cells of L. plantarum Lp115 for different periods of time. The target microorganism was monitored in the fecal microbiota via quantitative PCR (qPCR). L. plantarum was detected and quantified in all of the subjects during the ingestion periods. The differences between the L. plantarum levels at time zero and during all the different ingestion periods were statistically significant (P = 0.001). However, at 15 and 45 days after discontinuing supplementation, the number of lactobacilli was reduced to the baseline level (those at time zero). A longer period with L. plantarum in the diet did not result in increased levels of this bacterium in the stool, based on postconsumption evaluations (P = 0.001). The qPCR method was specific and sensitive for L. plantarum quantification in such a complex microbial environment as the gastrointestinal tract.  相似文献   
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