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41.
Airborne particles (pollens and fungal spores) are recognized as important causes of allergies and many other pathologies whose main symptoms are usually associated with respiratory problems. In addition, these particles seem to be responsible for clinical symptoms of oculorhinitis and bronchial asthma. Many authors showed how pollen and spore concentrations are critically linked to meteorological conditions, while other studies investigated the possibility to estimate these concentrations through meteorological parameters. So, many different approaches have been proposed, and one of the most sophisticated is based on the use of a complex artificial neural network architecture. Once the neural device is calibrated using simultaneous time series of observed meteorological parameters and airborne biological particles, it is straightforward to use the Neural Network to predict spore concentrations using operational Limited Area Meteorological Model. In a previous work, it has been shown that the MM5 meteorological model developed by National Center for Atmospheric Research and Pennsylvania State University can be coupled with the above-cited neural predictor to provide a good prediction of Alternaria and Pleospora spore in the location of L’Aquila (Central Italy). Following the same approach, this work aims to provide the mapping of spore concentration over a wide area covered by high-resolution meteorological prediction in Central Italy. The complex patterns of fungal spore concentrations in selected areas will be described, and the high temporal variability of such fields will be discussed as well. The possibility to infer useful information from the predicted pattern of spore concentrations is discussed, as an example it appears that for people suffering from allergy to fungal spores is more comfortable to spend summertime close to the east coast of Italian Peninsula respect to the west coast. A further step of this work may easily lead to an operational use of the model for supporting the clinical management of allergies and for establishing a preventive strategy in agriculture to avoid unsafe and useless pollution of atmosphere, crops and fields.  相似文献   
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The different actions exerted by pallidum and caudate nucleus on electrically induced epileptic activity of hippocampus were analyzed. Caudate appeared to inhibit hippocampal after discharges duration (HAD) while the globus pallidus exerted a facilitatory effect on HAD duration. Both effects were maximal when conditioning stimulation immediately preceded hippocampal test stimulation. The results are discussed considering reciprocal functional connections of the two striatal structures.  相似文献   
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Elucidating genetic mechanisms of adaptation is a goal of central importance in evolutionary biology, yet few empirical studies have succeeded in documenting causal links between molecular variation and organismal fitness in natural populations. Here we report a population genetic analysis of a two-locus α-globin polymorphism that underlies physiological adaptation to high-altitude hypoxia in natural populations of deer mice, Peromyscus maniculatus. This system provides a rare opportunity to examine the molecular underpinnings of fitness-related variation in protein function that can be related to a well-defined selection pressure. We surveyed DNA sequence variation in the duplicated α-globin genes of P. maniculatus from high- and low-altitude localities (i) to identify the specific mutations that may be responsible for the divergent fine-tuning of hemoglobin function and (ii) to test whether the genes exhibit the expected signature of diversifying selection between populations that inhabit different elevational zones. Results demonstrate that functionally distinct protein alleles are maintained as a long-term balanced polymorphism and that adaptive modifications of hemoglobin function are produced by the independent or joint effects of five amino acid mutations that modulate oxygen-binding affinity.  相似文献   
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Coupling reagents resembling the structure of Merrifield resin were designed and prepared from 2-chloro-4,6-dibenzyloxy-1,3,5-triazine and the different tertiary bases N-methylmorpholine, N-methylpiperidine, and DABCO. As previously observed for DMTMM, the appropriate N-(4,6-dibenzyloxy-1,3,5-triazin-2-yl) ammonium chloride salts were not suitable as efficient coupling reagents because of their low stability. On the other hand, the stability of the N-(4,6-dibenzyloxy-1,3,5-triazin-2-yl) ammonium tetrafluoroborates was suitable enough for prolonged storage and convenient application in SPPS. Moreover, we observed that the superactive intermediates formed during activation of Fmoc–Aib–OH with 4,6-dibenzyloxy-1,3,5-triazine-based coupling reagents lead to an increase in its concentration inside the polystyrene resin. Therefore, we hypothesize that this increase can enhance efficiency of 4,6-dibenzyloxy-1,3,5-triazine-based coupling reagents in SPPS.  相似文献   
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CDKN1B encodes the cyclin‐dependent kinase inhibitor p27/Kip1. CDKN1B mutations and polymorphisms are involved in tumorigenesis; specifically, the V109G single nucleotide polymorphism has been linked to different tumours with controversial results. Multiple endocrine neoplasia type 1 (MEN1) is a rare autosomal dominant syndrome, characterized by the development of different types of neuroendocrine tumours and increased incidence of other malignancies. A clear genotype–phenotype correlation in MEN1 has not been established yet. In this study, we assessed whether the CDKN1B V109G polymorphism was associated with the development of aggressive tumours in 55 consecutive patients affected by MEN1. The polymorphism was investigated by PCR amplification of germline DNA followed by direct sequencing. Baseline and follow‐up data of tumour types and their severity were collected and associated with the genetic data. MEN1‐related aggressive and other malignant tumours of any origin were detected in 16.1% of wild‐type and 33.3% of polymorphism allele‐bearing patients (P = NS). The time interval between birth and the first aggressive tumour was significantly shorter in patients with the CDKN1B V109G polymorphism (median 46 years) than in those without (median not reached; P = 0.03). Similarly, shorter was the time interval between MEN1 diagnosis and age of the first aggressive tumour (P = 0.02). Overall survival could not be estimated as 96% patients were still alive at the time of the study. In conclusion, CDKN1B V109G polymorphism seems to play a role in the development of aggressive tumours in MEN1.  相似文献   
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We have provided the first evidence for specific heteromerization between the α(1A)-adrenoceptor (α(1A)AR) and CXC chemokine receptor 2 (CXCR2) in live cells. α(1A)AR and CXCR2 are both expressed in areas such as the stromal smooth muscle layer of the prostate. By utilizing the G protein-coupled receptor (GPCR) heteromer identification technology on the live cell-based bioluminescence resonance energy transfer (BRET) assay platform, our studies in human embryonic kidney 293 cells have identified norepinephrine-dependent β-arrestin recruitment that was in turn dependent upon co-expression of α(1A)AR with CXCR2. These findings have been supported by co-localization observed using confocal microscopy. This norepinephrine-dependent β-arrestin recruitment was inhibited not only by the α(1)AR antagonist Terazosin but also by the CXCR2-specific allosteric inverse agonist SB265610. Furthermore, Labetalol, which is marketed for hypertension as a nonselective β-adrenoceptor antagonist with α(1)AR antagonist properties, was identified as a heteromer-specific-biased agonist exhibiting partial agonism for inositol phosphate production but essentially full agonism for β-arrestin recruitment at the α(1A)AR-CXCR2 heteromer. Finally, bioluminescence resonance energy transfer studies with both receptors tagged suggest that α(1A)AR-CXCR2 heteromerization occurs constitutively and is not modulated by ligand. These findings support the concept of GPCR heteromer complexes exhibiting distinct pharmacology, thereby providing additional mechanisms through which GPCRs can potentially achieve their diverse biological functions. This has important implications for the use and future development of pharmaceuticals targeting these receptors.  相似文献   
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