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PURPOSE: In an attempt to identify Müller cell-specific promoters and to better understand the gene regulatory mechanisms in retinal glial cells, the expression of the glial fibrillary acidic protein (GFAP) gene was studied in Müller cell cultures and in GFAP-enhanced green fluorescent protein (EGFP) transgenic mice. METHODS: A transfection assay of GFAP-luciferase constructs carrying a series of nested deletions was performed in an established Müller cell line. For in vivo analysis, transgenic mice were generated by injecting a construct carrying a 2.5-kb, 5' fragment of the mouse GFAP gene linked to the EGFP gene. Isolated retinas from transgenic mice were screened for GFP expression. Subsequently, the identity of the GFP-expressing cells was established by immunostaining cryostat sections of the retina with antibodies against Müller cell antigenic markers. Induction of the transgene and the endogenous GFAP gene was examined by injecting ciliary neurotrophic factor (CNTF) into the eye. RESULTS: The DNA transfection data suggested that proximal 5' sequences of the GFAP gene are sufficient to direct high-level reporter expression in Müller cell cultures. In transgenic mice, GFP fluorescence appeared in radially oriented processes that spanned almost the entire thickness of the retina. Immunostaining with antibodies to cellular retinaldehyde-binding protein (CRALBP) and glutamine synthetase showed that the GFP-expressing cells were Müller cells. GFP-expressing Müller cells were observed in the retinas of both albino and pigmented transgenic mice. In eyes injected with CNTF, both GFP and GFAP levels were highly elevated. These observations suggest that the 2.5-kb, 5' GFAP sequence can direct inducible reporter gene expression in Müller cells. In addition to Müller cells, a few GFP-labeled astrocytes were present in the adult retina. In the developing retina, GFP-expressing astrocytes were first present at the optic nerve head, and as development progressed, the cells gradually moved toward the periphery of the retina and acquired their adult, stellate morphology. CONCLUSIONS: The present study shows that the 2.5-kb, 5' flanking region of the mouse GFAP gene can be used to express GFP, and possibly other genes, specifically in Müller cells in the mouse retina. Furthermore, expression of the transgene can be upregulated by intravitreal injection of CNTF.  相似文献   
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Based on current findings, the presence of NPM1 mutations in acute myeloid leukemia (AML) patients is associated with an increased probability of complete remission (CR) and better overall survival (OS). We determined the incidence and prognostic relevance of NPM1 mutations, their association with FLT3 and IDH mutations, and other clinical characteristics in Serbian adult AML patients. Samples from 111 adult de novo AML patients, including 73 AML cases with a normal karyotype (NK-AML), were studied. NPM1, FLT3, and IDH mutations were detected by PCR and direct sequencing. NPM1 mutations were detected in 22.5% of patients. The presence of NPM1 mutations predicted a low CR rate and shorter OS. NPM1 mutations showed an association with both FLT3 and IDH mutations. Survival analysis based on NPM1/FLT3 mutational status revealed a lower OS for NPM1(+)/FLT3(-) compared to the NPM1(-)/FLT3(-) group in NK-AML patients. The lack of impact or unfavorable prognostic effect of NPM1 mutations found in this study can be assigned to a small cohort of analyzed AML patients, as can the presence of FLT3 and IDH mutations or other genetic lesions that cooperate with NPM1 mutations influencing prognosis.  相似文献   
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The aim of our study was to evaluate whether neo-vascularization of the carotid plaque can be accurately assessed by visual analysis of contrast-enhanced ultrasound images and whether these findings correlate with intensity-over-time curve analysis (ITC) and histopathology. Patients with ≥50% symptomatic or ≥60% asymptomatic stenosis according to European Carotid Surgery Trial criteria were included. Four investigators evaluated contrast enhancement visually (three grades), with positive agreement when three or more investigators were unanimous. ITC analysis of contrast enhancement was performed in the plaque and in the lumen. Histopathology (microvessel density with CD34 + staining) was completed when endarterectomy was performed. Visual grading (33 patients, inter-observer agreement = 94%) correlated significantly with ITC analysis (p = 0.03). Histopathology (n = 19) revealed a larger CD34 + area in patients with grade 1/2 versus grade 0 (p = 0.03). Visual analysis of neo-vascularization by means of contrast-enhanced ultrasound imaging is accurate and reproducible, with significant correlations with ITC and histopathology.  相似文献   
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Different mechanisms of blunt trauma producing carotid artery false aneurysms are described in literature. We report one such case caused by combination of two mechanisms: accidental hyperextension of the neck, and subsequent sudden forceful hit by a ball during the water polo match.  相似文献   
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Myelodysplastic syndromes (MDS) are rare disorders in children. Molecular mechanisms underlying MDS in children are not yet completely understood. Considering the role of FMS and TP53 gene mutations in adult MDS patients, we analyzed mutations of these genes in a cohort of 35 children with MDS. Single-strand conformation polymorphism polymerase chain reaction analysis performed on FMS codon 969 and TP53 exons 5-9 showed no mutations in the analyzed sequences. Our results suggest that molecular mechanisms of MDS evolution in children are different from those in adults.  相似文献   
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First impressions profoundly influence our attitudes and behavior toward others. However, little is known about whether and to what degree the cognitive processes that underlie impression formation depend on the domain of the available information about the target person. To investigate the neural bases of the influence of verbal as compared to nonverbal information on interpersonal judgments, we identified brain regions where the BOLD signal parametrically increased with increasing strength of evaluation based on either short text vignettes or mimic and gestural behavior. While for verbal stimuli the increasing strength of subjective evaluation was correlated with increased neural activation of precuneus and posterior cingulate cortex (PC/PCC), a similar effect was observed for nonverbal stimuli in the amygdala. These findings support the assumption that qualitatively different cognitive operations underlie person evaluation depending upon the stimulus domain: while the processing of nonverbal person information may be more strongly associated with affective processing as indexed by recruitment of the amygdala, verbal person information engaged the PC/PCC that has been related to social inferential processing.  相似文献   
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