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101.
PGD(2) is the major mediator released by mast cells during allergic responses, and it acts through two different receptors, the D prostanoid receptor 1 (DP1) and DP2, also known as CRTH2. Recently, it has been shown that PGD(2) inhibits the migration of epidermal Langerhans cells to the skin draining lymph nodes (LNs) and affects the subsequent cutaneous inflammatory reaction. However, the role of PGD(2) in the pulmonary immune response remains unclear. Here, we show that the intratracheal instillation of FITC-OVA together with PGD(2) inhibits the migration of FITC(+) lung DC to draining LNs. This process is mimicked by the DP1 agonist BW245C, but not by the DP2 agonist DK-PGD(2). The ligation of DP1 inhibits the migration of FITC-OVA(+) DCs only temporarily, but still inhibits the proliferation of adoptively transferred, OVA-specific, CFSE-labeled, naive T cells in draining LNs. These T cells produced lower amounts of the T cell cytokines IL-4, IL-10, and IFN-gamma compared with T cells from mice that received FITC-OVA alone. Taken together, our data suggest that the activation of DP receptor by PGD(2) may represent a pathway to control airway DC migration and to limit the activation of T cells in the LNs under steady state conditions, possibly contributing to homeostasis in the lung.  相似文献   
102.
The effect of heat stress on hexaploid wheat grain proteome was recently analyzed in our previous works. Proteomic tools allowed the characterization of heat-responsive proteins of total endosperm, composed mainly of prolamins. The present work completes this study; our aim was to analyze the effect of heat stress on the water-soluble fraction, composed essentially of albumins and globulins. These proteins were separated by two-dimensional electrophoresis (2-DE), visualized by Coomassie Brilliant Blue (CBB) staining and analyzed by Melanie-3 software. Of the 43 heat-changed proteins, 24 were found to be up-regulated whereas 19 spot proteins were down-regulated. All of these proteins were subjected to matrix-assisted laser desorption/ionization-time of flight-mass spectrometry (MALDI-TOF-MS) followed by database searching which allowed the identification of 42 spots. Of these, some were enzymes involved in different metabolic pathways of plants, such as granule-bound starch synthase and glucose-1-phosphate adenyltransferase, involved in the starch synthesis pathway; beta-amylase, involved in carbohydrate metabolism, and the ATP synthase beta-chain that was related to four heat-decreased proteins. Moreover, five heat up-regulated proteins showed similarities with small heat shock proteins while three other spots were related to elongation factors or eucaryotic translation initiation factors. Proteins involved in abiotic stresses or in plant defense mechanism were also identified and are discussed.  相似文献   
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BAS 317 00F was not toxic to the total count of fungi after 2 days but was regularly significantly toxic at the three doses after 5, 20 and 40 days and toxic at the low and the high doses after 80 days. In the agar medium, it was toxic to the counts of total fungi, Aspergillus, A. terreus, Rhizopus oryzae and Mucor racemosus at the high dose. Only the mycelial growth of Trichoderma viride which was significantly inhibited by the three doses when this fungicide was added to the liquid medium.Polyram-Combi induced two effects on the total population of soil fungi. One inhibitory and this was demonstrated almost regularly after 2, 10 and 40 days and the other stimulatory after 80 days of treatment with the low and the high doses. In the agar medium, this fungicide was very toxic to total fungi and to almost all fungal genera and species at the three doses. Several fungi could survive the high dose. In liquid medium, the test fungi showed variable degree of sensitivity and the most sensitive was Gliocladium roseum which was completely eradicated by the three doses.  相似文献   
106.
Friedreich ataxia is a neurodegenerative disorder with autosomal recessive inheritance. Precise linkage mapping of the Friedreich ataxia locus (FRDA) in 9q13-q21 should lead to the isolation of the defective gene by positional cloning. The two closest DNA markers, D9S5 and D9S15, show very tight linkage to FRDA, making difficult the ordering of the three loci. We present a linkage study of three large Friedreich ataxia families of Tunisian origin, with several multiallelic markers around D9S5 and D9S15. Haplotype data were used to investigate genetic homogeneity of the disease in these geographically related families. A meiotic recombination was found in a nonaffected individual, which excludes a 150-kb segment, including D9S15, as a possible location for the Friedreich ataxia gene and which should orient the search in the D9S5 region.  相似文献   
107.
Medicated chewing gums (MCGs) represent a unique platform for drug delivery. They have been defined as solid single-dose preparations, which may contain more than one active pharmaceutical ingredient (API) with base consisting primarily of gum that has to be chewed for a certain period of time. They mainly contain a tasteless masticatory gum base as the core with other minor nonmasticatory ingredients, such as flavors and sweeteners. Despite their advantages in drug delivery, MCGs remain a niche product due to the complexity of their formulation, lack of acceptable testing methods, and intricacy of their manufacturing. Few studies have been reported on their use, and most of the information on their composition and production could be found in patent search. The aim of this review is to provide an overview of gum composition, manufacturing process, and characterization. Due to the scarcity of studies concerning the evaluation of the mechanical properties of MCGs, greater emphasis was placed on the available performance tests and procedures for the estimation of their mechanical and textural properties. While very few tests have been recommended by the official pharmacopeias, several tests have been suggested for assessing the mechanical properties of MCGs in vitro. Properties, such as chewiness, elasticity, and firmness, of chewing gums during mastication are imperative quality attributes that have been found to strongly correlate with gum composition and mouth feel.  相似文献   
108.
Phytoremediation offers owners and managers of metal-contaminated sites an innovative and cost-effective option to address recalcitrant environmental contamination. The use of plants to restore or stabilize contaminated sites, known as phytoremediation, takes advantage of the natural abilities of plants to take up, accumulate or store metals. This includes the use of plants that tolerate and accumulate metals at high levels for phytoextraction and the use of plants growing under conditions that are toxic to other plants, for preventing, for example, soil erosion (phytostabilisation). Rapeseed (Brassica napus L.) was shown to be able to accumulate substantial amounts of metals combined with high biomass. Brassica napus was therefore selected for heavy metal (HM) tolerance and accumulation through in vitro selection. A selective pressure applied during the neoformation process from transversal thin cell layers (tTCLs) allowed us to select tolerant cells and tissues. Toxic metals (such as Zn) were added to the culture media in order to select zinc-tolerant plants. Exerting a selective pressure during tTCLs regeneration aimed at selecting plants with exceptional zinc tolerance and/or accumulating capacity. The morphological and physicochemical characteristics of regenerated plants cultivated in greenhouse appeared to depend very significantly on the concentration of ZnSO(4) applied during the neoformation process. Plants regenerated in the presence of ZnSO(4) at 100 microM exhibited a greater size and a higher biomass together with flowering precocity. The contents of zinc, chlorophyll, and proline were modified in the regenerated plants. Pre-treatment with an excess of ZnSO(4) (>500 microM) was responsible for a percentage of tTCLs intolerance above 96%. With lower Zn concentrations (100-250 microM), the survival rates (33-15%) were higher.  相似文献   
109.
To investigate the effects of iontophoresis–ultraviolet A (UVA) cross-linking (CXL) with hypotonic riboflavin solution on the ultrastructural changes in the lamellae, collagen fibrils (CFs), and proteoglycans (PGs) in the central and peripheral stroma of the human corneal buttons. The iontophoresis method was used for the trans-epithelial application of hypotonic riboflavin in ex vivo corneal culture for 5 min. The corneas were irradiated using three methods: Group 1 (G1), a UVA irradiance of 3 mW/cm2 for 30 min; Group 2 (G2), a UVA irradiance of 10 mW/cm2 for 9 min; Group 3 (G3), without UVA irradiation. Three untreated corneas were used as controls (G0). After the CXL procedure, the corneas were processed for electron microscopy. The CF diameter and PGs in each sample were analyzed using the iTEM program. The keratocyte organelles and stromal architecture in the peripheral cornea were better preserved than those in the central cornea. In G1 and G2, the mean CF diameter in the peripheral cornea was significantly higher than that in the central cornea. In G3, the CF diameter in the central cornea was significantly larger than that in the peripheral cornea. Furthermore, differences in PG area size were observed between the central and peripheral corneas in all groups. Riboflavin + UVA application at 3 mW/cm2 for 30 min and 10 mW/cm2 for 9 min was a suitable method of CXL; however, 3 mW/cm2 for 30 min improved the organization and size of the collagen fibrils. CXL treatment applied at the periphery was more effective than that applied at the center.Keyword: Collagen fibrils, Proteoglycans, Cornea, Iontophoresis, Ultraviolet A  相似文献   
110.
Arthropod-borne viruses are a group of the most important emerging pathogens. They cause a range of diseases in vertebrate hosts and threaten human health (Gan and Leo, 2014). The global distribution of arboviruses is associated with the vector which is strongly affected by changes in environmental conditions. Dengue virus (DENV) and Chikungunya virus (CHIKV), which cause high annual infected cases and have an increasing geographic distribution, are transmitted by Aedes spp. mosquitoes, in particular Ae. albopictus and Ae. Aegypti (Presti et al., 2014; Higuera and Ramírez, 2018). Although, the main vector of dengue virus, Ae. aegypti, was not detected in Iran, other possible important vectors such as Ae. Albopictus and Ae. unilineatus were recorded (Doosti et al., 2016; Yaghoobi-Ershadi et al., 2017). West Nile virus (WNV), a member of the genus Flaviviruses, is one of the most widespread arboviruses (Chancey et al., 2015). The epidemiological evidence of WNV in different hosts in Iran was found (Bagheri et al., 2015), and the circulation of WNV in the main vector, Culex pipiens s.l. and Cx. pipiens, has been proved (Shahhosseini et al., 2017). Due to limited information on the situation of CHIKV, DENV and WNV in Iran, we performed a wide geographical investigation to determine the prevalence of IgG specific antibodies in human samples as well as the genome of WNV, CHIKV and DENV in mosquitoes.  相似文献   
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