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61.
Prisoners are at increased risk of suicide. Investigation of both individual and environmental risk factors may assist in developing suicide prevention policies for prisoners and other high-risk populations. We conducted a matched case-control interview study with 60 male prisoners who had made near-lethal suicide attempts in prison (cases) and 60 male prisoners who had not (controls). We compared levels of depression, hopelessness, self-esteem, impulsivity, aggression, hostility, childhood abuse, life events (including events occurring in prison), social support, and social networks in univariate and multivariate models. A range of psychosocial factors was associated with near-lethal self-harm in prisoners. Compared with controls, cases reported higher levels of depression, hopelessness, impulsivity, and aggression, and lower levels of self-esteem and social support (all p values <0.001). Adverse life events and criminal history factors were also associated with near-lethal self-harm, especially having a prior prison spell and having been bullied in prison, both of which remained significant in multivariate analyses. The findings support a model of suicidal behaviour in prisoners that incorporates imported vulnerability factors, clinical factors, and prison experiences, and underscores their interaction. Strategies to reduce self-harm and suicide in prisoners should include attention to such factors.  相似文献   
62.
The expression of the beta1 family of integrins was determined in thyroid follicular cells from patients with Graves' disease (GD). Integrin expression was quantitated by flow fluorocytometry of single cell suspensions with antibodies against the common beta1 chain and the alpha1-alpha6 subunits. Results indicated that also in thyroid glands of GD, as previously observed in nodular goiters, two follicular cell populations with different patterns of beta1 integrin expression coexist (VLAalpha3beta1 and VLAalpha1,3,5,6beta1). The VLAalpha1,3,5,6beta1 thyrocyte population in GD was more abundant than in nodular goiters, ranging from 40 to 70% of the total follicular cells and the overall expression of the beta1 integrins was a two-fold higher. In thyrocytes from patients with GD cultured in vitro, alpha3 and alpha2 expression was regulated by cell-to-cell contact as previously described in normal thyroid cells, while the expression of alpha1, alpha5 and alpha6 was quickly lost during the culture. Our data suggest that the integrin profile of the VLAalpha1,3,5,6beta1 thyrocyte population in GD is induced by micro-environmental conditions rather than being the expression of a constitutive phenotype.  相似文献   
63.

Background

Thymosin beta 4 (Tβ4) is a member of beta-thymosins, a family of peptides that play essential roles in many cellular functions. A recent study from our group suggested a role for Tβ4 in the development of human salivary glands. The aim of this study was to analyze the expression of Tβ4 in the human gut during development, and in the adult.

Methodology/Principal Findings

Immunolocalization of Tβ4 was studied in autoptic samples of tongue, oesophagus, stomach, ileum, colon, liver and pancreas obtained from two human foetuses and two adults. Tβ4 appeared unevenly distributed, with marked differences between foetuses and adults. In the stomach, superficial epithelium was positive in foetuses and negative in adults. Ileal enterocytes were strongly positive in the adult and weakly positive in the foetuses. An increase in reactivity for Tβ4 was observed in superficial colon epithelium of adults as compared with the foetuses. Striking differences were found between foetal and adult liver: the former showed a very low reactivity for Tβ4 while in the adult we observed a strong reactivity in the vast majority of the hepatocytes. A peculiar pattern was found in the pancreas, with the strongest reactivity observed in foetal and adult islet cells.

Significance

Our data show a strong expression of Tβ4 in the human gut and in endocrine pancreas during development. The observed differential expression of Tβ4 suggests specific roles of the peptide in the gut of foetuses and adults. The observed heterogeneity of Tβ4 expression in the foetal life, ranging from a very rare detection in liver cells up to a diffuse reactivity in endocrine pancreas, should be taken into account when the role of Tβ4 in the development of human embryo is assessed. Future studies are needed to shed light on the link between Tβ4 and organogenesis.  相似文献   
64.
Psoralens are well-known photosensitizers, and 8-methoxypsoralen and 4,5',8-trimethylpsoralen are widely used in photomedicine as "psoralens plus UVA therapy" (PUVA), in photopheresis, and in sterilization of blood preparations. In an attempt to improve the therapeutic efficiency of PUVA therapy and photopheresis, four poly(ethylene glycol) (PEG)-psoralen conjugates were synthesized to promote tumor targeting by the enhanced permeability and retention (EPR) effect. Peptide linkers were used to exploit specific enzymatic cleavage by lysosomal proteases. A new psoralen, 4-hydroxymethyl-4',8-dimethylpsoralen (6), suitable for polymer conjugation was synthesized. The hydroxy group allowed exploring different strategies for PEG conjugation, and linkages with different stability such ester or urethanes were obtained. PEG (5 kDa) was covalently conjugated to the new psoralen derivative using four different linkages, namely, (i) direct ester bond (7), (ii) ester linkage with a peptide spacer (8), (iii) a carbamic linker (9), and (iv) a carbamic linker with a peptide spacer (12). The stability of these new conjugates was assessed at different pHs, in plasma and following incubation with cathepsin B. Conjugates 7 and 8 were rapidly hydrolyzed in plasma, while 9 was stable in buffer and in the presence of cathepsin B. As expected, only the conjugates containing the peptide linker released the drug in presence of cathepsin B. In vitro evaluation of the cytotoxic activity in the presence and absence of light was carried out in two cell lines (MCF-7 and A375 cells). Conjugates 7 and 8 displayed a similar activity to the free drug (probably due to the low stability of the ester linkage). Interestingly, the conjugates containing the carbamate linkage (9 and 12) were completely inactive in the dark (IC50 > 100 microM in both cell lines). However, antiproliferative activity become apparent after UV irradiation. Conjugate 12 appears to be the most promising for future in vivo evaluation, since it was relatively stable in plasma, which should allow tumor targeting and drug release to occur by cathepsin B-mediated hydrolysis.  相似文献   
65.
Performances of the new automatic system COBAS AmpliPrep/COBAS TaqMan 48 (CAP/CTM) (Roche, Branchburg, NJ) for HBV DNA extraction and real-time PCR quantification were assessed and compared with the endpoint PCR COBAS AMPLICOR HBV Monitor (CAHBM, Roche). Analytical evaluation with proficiency panels from UK National External Quality Assessment Scheme (UK NEQAS) over a 1-year period of distribution showed that CAP/CTM correctly measured HBV DNA levels with a close correlation between expected and observed values (r=0.995). Clinical evaluation as tested with samples from 11 HBsAg-positive patients undergoing antiviral therapy (71 serial specimens of plasma), demonstrated excellent correlation with CAHBM (r=0.958, mean difference in quantitation: 0.14 log, IU/ml), but CAP/CTM detected longer period of residual viremia. HBV DNA reduction was much higher in the combination schedule (Lamivudine+Adefovir), than in Adefovir monotherapy (5.1 vs. 3.5 logs). In conclusion, CAP/CTM allows for an accurate and standardized quantification of HBV DNA in high through-put laboratories. Due to it high sensitivity, it may further improve the detection of emerging drug resistance strains and the assessment of antiviral therapy.  相似文献   
66.
The reaction of cis- and trans-[PtCl2(NCCH2Ph)2] with a 5-fold excess of MeNH2 and Me2NH in CH2Cl2 at −10 °C affords in high yield the bis-amidine derivatives cis- and trans-[PtCl2{Z-N(H)C(NHMe)CH2Ph}2] (1a, 2a) and cis- and trans-[PtCl2{E-N(H)C(NMe2)CH2Ph}2] (3a, 4a), respectively. The complexes were characterized by means of elemental analysis, multinuclear NMR and FT-IR techniques. The X-ray diffraction analysis was carried out for trans-[PtCl2{Z-N(H)C(NHMe)CH2Ph}2] (2a).Moreover, the in vitro cytotoxicity for the new derivatives was evaluated in a wide panel of human tumor cell lines.  相似文献   
67.
A computed tomographic scan in an 80-year-old man with a urinary obstruction demonstrated a solitary space-occupying liver lesion, which was clinically suspected to be a metastatic carcinoma. Fine needle aspiration (FNA) of the mass produced a smear containing atypical, possibly malignant, cells. Correlation of the FNA findings with the patient's history resulted in a cytologic diagnosis of an intrahepatic focus of extramedullary hematopoiesis (EMH). This case shows FNA biopsy to be a reliable method of diagnosing foci of EMH, but also demonstrates the potential pitfall of diagnosing atypical megakaryocytes as malignant in FNA smears. EMH should be considered in the differential diagnosis of patients with bone marrow disorders and mass lesions in extramedullary sites.  相似文献   
68.
Seven Italian populations of twaite shad Alosa fallax from Northern and Central Italy were investigated to assess genetic diversity by Cytochrome b (Cytb) gene sequencing. The two ecotypes historically referred to landlocked and anadromous populations were investigated for the first time from a genetic point of view, to clarify their phylogenetic relationships. Moreover, results obtained from populations coming from separated Adriatic and Tyrrhenian basins were compared with data assessed in samples of allis shad Alosa alosa from the Atlantic basin. All the Italian samples were recognized at species level as A. fallax, differing for five mutations from A. alosa. The analyses confirmed the occurrence of a single phylogenetic lineage and of a single species within Italian waters, in both landlocked and migratory populations. The minimum spanning network identified six haplotypes for A. fallax and two haplotypes for A. alosa. The neighbour-joining tree and the maximum likelihood on the Cytb gene sequences confirmed two distinct lineages for A. alosa and A. fallax, without evidence of a separation at specific level within the A. fallax group. A weak separation due to incipient population differentiation was detected between anadromous and landlocked Italian populations, supporting the idea of a recent separation. The molecular data herein collected do not support the existence of the already controversial incipient species Alosa agone. Despite this, the two ecotypes could be considered as different management units from a conservation viewpoint.  相似文献   
69.
Di‐(2‐ethylhexyl) phthalate (DEHP) is a commonly used plasticizer with endocrine‐disrupting properties. In this study, we used an equine model to investigate DEHP concentrations in ovarian follicular fluid (FF), and to determine the effects of exposure of oocytes to potentially toxic concentrations of DEHP during in vitro maturation (IVM) on embryo development and quality. Embryo development was evaluated using time‐lapse monitoring (TLM), a photomicroscopic tool that reveals abnormalities in cleavage kinetics unobservable by conventional morphology assessment. Blastocyst bioenergetic/oxidative status was assessed by confocal analysis. The possibility that verbascoside (VB), a bioactive polyphenol with antioxidant activity, could counteract DEHP‐induced oocyte oxidative damage, was investigated. DEHP was detected in FF and in IVM media at concentrations up to 60 nM. Culture of oocytes in the presence of 500 nM DEHP delayed second polar body extrusion, reduced duration of the second cell cycle, and increased the percentage of embryos showing abrupt multiple cleavage, compared with controls. Mitochondrial activity and intracellular levels of reactive oxygen species were reduced in blastocysts from DEHP‐exposed oocytes. VB addition during IVM limited DEHP‐induced blastocyst damage. In conclusion, DEHP is detectable in equine FF and culture medium, and oocyte exposure to increased concentrations of DEHP during IVM affects preimplantation embryo development. Moreover, TLM, reported for the first time in the horse in this study, is an efficient tool for identifying altered morphokinetic parameters and cleavage abnormalities associated with exposure to toxic compounds.  相似文献   
70.
Lung infection by Burkholderia species, in particular Burkholderia cenocepacia, accelerates tissue damage and increases post-lung transplant mortality in cystic fibrosis patients. Host-microbe interplay largely depends on interactions between pathogen-specific molecules and innate immune receptors such as Toll-like receptor 4 (TLR4), which recognizes the lipid A moiety of the bacterial lipopolysaccharide (LPS). The human TLR4·myeloid differentiation factor 2 (MD-2) LPS receptor complex is strongly activated by hexa-acylated lipid A and poorly activated by underacylated lipid A. Here, we report that B. cenocepacia LPS strongly activates human TLR4·MD-2 despite its lipid A having only five acyl chains. Furthermore, we show that aminoarabinose residues in lipid A contribute to TLR4-lipid A interactions, and experiments in a mouse model of LPS-induced endotoxic shock confirmed the proinflammatory potential of B. cenocepacia penta-acylated lipid A. Molecular modeling combined with mutagenesis of TLR4-MD-2 interactive surfaces suggests that longer acyl chains and the aminoarabinose residues in the B. cenocepacia lipid A allow exposure of the fifth acyl chain on the surface of MD-2 enabling interactions with TLR4 and its dimerization. Our results provide a molecular model for activation of the human TLR4·MD-2 complex by penta-acylated lipid A explaining the ability of hypoacylated B. cenocepacia LPS to promote proinflammatory responses associated with the severe pathogenicity of this opportunistic bacterium.  相似文献   
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