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101.
BACKGROUND: Many factors can negatively affect growth in thalassemic patients, and hypogonadism has been considered as the main factor responsible for their pubertal growth failure. OBJECTIVE: To evaluate the influence of hypogonadism and its treatment on pubertal growth and final height in thalassemic patients. METHODS: We compared the growth of 28 hypogonadal thalassemic patients in whom puberty was induced to that of 25 patients in whom puberty occurred spontaneously. RESULTS: In both groups of patients we observed reduced peak height velocity (induced puberty: females 4.9 +/- 2.1, males 6.0 +/- 1.8 cm/year; spontaneous puberty: females 6.1 +/- 1.5, males 7.3 +/- 2.1 cm/year) and pubertal height gain (induced puberty: females 11.3 +/- 4.0, males 18.0 +/- 4.5 cm/year; spontaneous puberty: females 15.8 +/- 2.7, males 18.1 +/- 5.3 cm/year) and a short final height (induced puberty: females -1.8 +/- 0.7, males -2.1 +/- 1.0 SDS; spontaneous puberty: females -2.3 +/- 1.0, males -1.9 +/- 1.0 SDS). CONCLUSIONS: Poor pubertal growth is present in thalassemic patients regardless of hypogonadism. Other factors are responsible for the reduced growth spurt and the final short stature observed in these patients.  相似文献   
102.
The diagnosis of cutaneous Mycobacterium marinum infection is frequently presumptive, as detection by conventional methods is difficult. We describe a patient with granulomatous skin lesions on the right dorsal hand and forearm. Histological examinations were presumptive for mycobacterium lesions. We identified Mycobacterium marinum directly in the patient's lesional skin biopsy combining polymerase chain reaction (PCR) amplification using Mycobacterium genus-specific primers, and subsequent restriction enzyme analysis enabling identification to the species level. The symptoms were no longer present after specific therapy, thereby confirming the initial diagnosis.  相似文献   
103.
Twenty-seven new Rhizobium isolates were obtained from root nodules of wild and crop legumes belonging to the genera Vicia, Lathyrus and Pisum from different agroecological areas in central and southern Italy. A polyphasic approach including phenotypic and genotypic techniques was used to study their diversity and their relationships with other biovars and species of rhizobia. Analysis of symbiotic properties and stress tolerance tests revealed that wild isolates showed a wide spectrum of nodulation and a marked variation in stress tolerance compared with reference strains tested in this study. All rhizobial isolates (except for the isolate CG4 from Galega officinalis) were presumptively identified as Rhizobium leguminosarum biovar viciae both by their symbiotic properties and the specific amplification of the nodC gene. In particular, we found that the nodC gene could be used as a diagnostic molecular marker for strains belonging to the bv. viciae. RFLP-PCR 16S rDNA analysis confirms these results, with the exception of two strains that showed different RFLP-genotypes from those of the reference strains of R. leguminosarum bv. viciae. Analysis of intraspecies relationship among strains by using the RAPD-PCR technique showed a high level of genetic polymorphism, grouping our isolates and reference strains into six different major clusters with a similarity level of 20%. Data from seven parameters of phenotypic and genotypic analyses were evaluated by using principal component analysis which indicated the differences among strains and allowed them to be divided into seven different groups.  相似文献   
104.
Nano-sized particles of ceramic and metallic materials are generated by high-tech industrial activities, and can be generated from worn-out replacement and prosthetic implants. The interaction with the human body of such nanoparticles has been investigated, with a particular emphasis on innate defence mechanisms. Human macrophages (PMA-differentiated myelomonocytic U-937 cells) were exposed in vitro to non-toxic concentrations of TiO(2), SiO(2), ZrO(2), or Co nanoparticles, and their inflammatory response (expression of TLR receptors and co-receptors, and cytokine production) was examined. Expression of TLR receptors was generally unaffected by exposure to the different nanoparticles, except for some notable cases. Exposure to nanoparticles of ZrO(2) (and to a lesser extent TiO(2)), upregulated expression of viral TLR receptors TLR3 and TLR7. Expression of TLR10 was also increased by TiO(2) and ZrO(2) nanoparticles. On the other hand, TLR9 expression was decreased by SiO(2) nano-particles, and expression of the co-receptor CD14 was inhibited by Co nanoparticles. Basal and LPS-induced production of cytokines IL-1beta, TNF-alpha, and IL-1Ra was examined in macrophages exposed to nanoparticles. SiO(2) nanoparticles strongly biased naive macrophages towards inflammation (M1 polarisation), by selectively inducing production of inflammatory cytokines IL-1beta and TNF-alpha. SiO(2) nanoparticles also significantly amplified the inflammatory phenotype of LPS-polarised M1 macrophages. Other ceramic nanoparticles had little influence on cytokine production, either in resting macrophages, or in LPS-activated cells. Generally, Co nanoparticles had an overall pro-inflammatory effect on naive macrophages, by reducing anti-inflammatory IL-1Ra and inducing inflammatory TNF-alpha. However, Co nanoparticles reduced production of IL-1beta and IL-1Ra, but not TNF-alpha, in LPS-polarised M1 macrophages. Thus, exposure to different nanoparticles can modulate, in different ways, the defence/inflammatory capacities of macrophages. A thorough analysis of these biasing effects may shed light on the mechanisms of pathogenesis of several diseases based on dysregulation of the immune response (allergies, autoimmunity, tumours).  相似文献   
105.
We describe histochemical techniques for detecting DNA within the osteocytic lacunae of ancient bones. The bones examined were fragments of femurs from two human individuals found in the Pompeian C. I. Polybius house and fragments of metacarpals from two horses (Equus sp.) found in the Pompeian “Casti Amanti” house. Both buildings were buried by the 79 A. D. Vesuvius eruption. Fragments of femurs from a modern horse, a modern swine and a modern amphibian also were studied as controls. Some bone sections were stained with two different DNA-specific fluorochromes, 4' -' 6-diamidino-2-phenylindole (DAPI) and chromomycin A3 (CMA), while others were stained by the Feulgen reaction. All of the techniques gave a positive reaction within the osteocytic lacunae. Histological analysis of the undecalcified, ground and unstained sections agreed well with results of bone sections stained with either the fluorochromes or the Feulgen reaction. Bones showing good histology also were positive by our DNA-specific stain. Histochemical and histological analyses correlated well with the success of DNA extraction and amplification. Using conventional DNA-specific histochemical techniques in conjunction with histological analysis can be useful in the study of DNA extracted from ancient bone remains while reducing both the amount of time and cost.  相似文献   
106.
Severe allergic reactions of unknown etiology,necessitating a hospital visit, have an important impact in the life of affected individuals and impose a major economic burden to societies. The prediction of clinically severe allergic reactions would be of great importance, but current attempts have been limited by the lack of a well-founded applicable methodology and the wide spatiotemporal distribution of allergic reactions. The valid prediction of severe allergies (and especially those needing hospital treatment) in a region, could alert health authorities and implicated individuals to take appropriate preemptive measures. In the present report we have collecterd visits for serious allergic reactions of unknown etiology from two major hospitals in the island of Crete, for two distinct time periods (validation and test sets). We have used the Normalized Difference Vegetation Index (NDVI), a satellite-based, freely available measurement, which is an indicator of live green vegetation at a given geographic area, and a set of meteorological data to develop a model capable of describing and predicting severe allergic reaction frequency. Our analysis has retained NDVI and temperature as accurate identifiers and predictors of increased hospital severe allergic reactions visits. Our approach may contribute towards the development of satellite-based modules, for the prediction of severe allergic reactions in specific, well-defined geographical areas. It could also probably be used for the prediction of other environment related diseases and conditions.  相似文献   
107.
108.
In Lovran (coastal Croatia), a unique forest/orchard of evenly mixed grafted marrons and naturally growing nongrafted sweet chestnut trees exists. This old chestnut population has been devastated by chestnut blight, caused by an aggressive introduced pathogenic fungus, Cryphonectria parasitica. However, initial observations indicated recovery of naturally growing chestnut trees in that area, mediated by Cryphonectria-associated hypovirus (Cryphonectria hypovirus 1 (CHV-1)). Such recovery was not observed on grafted trees. Genotyping both, we confirmed the clonal origin of the grafted ones—marrons. No significant difference was observed between fungal strains isolated from naturally growing trees and the ones from marrons regarding fungal vegetative compatibility types or the prevalence of CHV-1. A strong correlation was observed between the types of canker: active/deep-expanding versus healing callus or superficial necrosis and the absence or presence of CHV-1 in the fungal isolates, sampled from naturally growing trees (Spearman rho 0.686, p value 7.81?×?10?5, Kendall tau 0.686, p value 5.18?×?10?7). Such correlation was not observed on marrons (Spearman rho 0.236, p value 0.235, Kendall tau 0.236, p value 0.084), because, unexpectedly, active/deep-expanding cankers were often associated with hypovirulent fungal isolates. These data indicate that the lack or unequal distribution of naturally occurring hypovirulence were not the cause of substantial marron decay in Lovran. Ecological and age-dependant differences were ruled out because all sampled trees are growing in close proximity and are of similar age. The results imply that the marron genotype is especially vulnerable and its ability to recover is limited even when the hypovirulent strain of the fungus is present in the canker.  相似文献   
109.
During the summer of 2013 seven Italian Tyrolean Grey calves were born with abnormally short limbs. Detailed clinical and pathological examination revealed similarities to chondrodysplastic dwarfism. Pedigree analysis showed a common founder, assuming autosomal monogenic recessive transmission of the defective allele. A positional cloning approach combining genome wide association and homozygosity mapping identified a single 1.6 Mb genomic region on BTA 6 that was associated with the disease. Whole genome re-sequencing of an affected calf revealed a single candidate causal mutation in the Ellis van Creveld syndrome 2 (EVC2) gene. This gene is known to be associated with chondrodysplastic dwarfism in Japanese Brown cattle, and dwarfism, abnormal nails and teeth, and dysostosis in humans with Ellis-van Creveld syndrome. Sanger sequencing confirmed the presence of a 2 bp deletion in exon 19 (c.2993_2994ACdel) that led to a premature stop codon in the coding sequence of bovine EVC2, and was concordant with the recessive pattern of inheritance in affected and carrier animals. This loss of function mutation confirms the important role of EVC2 in bone development. Genetic testing can now be used to eliminate this form of chondrodysplastic dwarfism from Tyrolean Grey cattle.  相似文献   
110.
Alveolar epithelial type II cells (AT II) in which lung surfactant synthesis and secretion take place, are subjected to low magnitude stretch during normal breathing. The aim of the study was to explore the effect of mild stretch on phospholipase A(2) (PLA(2)) activation, an enzyme known to be involved in surfactant secretion. In A549 cells (a model of AT II cells), we showed, using a fluorometric assay, that stretch triggers an increase of total PLA(2) activity. Western blot experiments revealed that the cytosolic isoform cPLA(2) is rapidly phosphorylated under stretch, in addition to a modest increase in cPLA(2) mRNA levels. Treatment of A549 cells with selective inhibitors of the MEK/ERK pathway significantly attenuated the stretch-induced cPLA(2) phosphorylation. A strong interaction of cPLA(2) and pERK enzymes was demonstrated by immunoprecipitation. We also found that inhibition of PI3K pathway attenuated cPLA(2) activation after stretch, without affecting pERK levels. Our results suggest that low magnitude stretch can induce cPLA(2) phosphorylation through the MEK/ERK and PI3K-Akt pathways, independently.  相似文献   
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