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81.
BACKGROUND: Regulatory FOXP3+ T cells control immune responses of effector T cells. However, whether these cells regulate antidonor responses in the graft of cardiac allograft patients is unknown. Therefore, we analyzed the gene expression profiles of regulatory and effector T-cell markers during immunological quiescence and acute rejection. METHODS: Quantitative real-time polymerase chain reaction was used to analyze mRNA expression levels in time-zero specimens (n=24) and endomyocardial biopsies (EMB; n=72) of cardiac allograft patients who remained free from rejection (nonrejectors; n=12) and patients with at least one histologically proven acute rejection episode (rejectors; International Society for Heart and Lung Transplantation [ISHLT] rejection grade>2; n=12). RESULTS: For all analyzed regulatory and effector T-cell markers, mRNA expression levels were increased in biopsies taken after heart transplantation compared with those in time-zero specimens. Posttransplantation, the FOXP3 mRNA levels were higher in EMB assigned to a higher ISHLT rejection grade than the biopsies with grade 0: the highest mRNA levels were detected in the rejection biopsies (rejection grade>2; P=0.003). In addition, the mRNA levels of CD25, glucocorticoid-induced TNF receptor family-related gene, cytotoxic T lymphocyte-associated antigen 4, interleukin-2, and granzyme B were also significantly higher in rejecting EMB than in nonrejecting EMB (rejection grade相似文献   
82.
Scand J Caring Sci; 2013; 27; 44–50 Are informal caregivers less happy than noncaregivers? Happiness and the intensity of caregiving in combination with paid and voluntary work Informal caregivers are one of the pillars of home health care. In the Netherlands, the free help they provide to sick or disabled family members, acquaintances or friends exceeds the number of hours of home care provided by professionals. While the government welcomes their contribution, there is concern about the potential burden their work imposes on them. On the one hand, there is concern that informal caregiving could be experienced as a burden and diminish subjective well‐being; on the other, helping others as a meaningful activity might increase their subjective well‐being. Happiness ratings (as an indicator of subjective well‐being) of persons whose involvement in informal caregiving, voluntary work and paid work ranged from none to full time were analysed using multivariate regression models, which also took into account levels of physical disability and socio‐economic characteristics (age, sex, household composition, education level). The sample consisted of 336 informal caregivers and 1765 noncaregivers in the Dutch population. In line with the subjective well‐being assumption, the results suggest that caregivers are happier than noncaregivers when they provide care for <6 hours a week; and in line with the burden assumption, the results show that providing care for more than 11 hours a week is associated with lower levels of happiness. Other results contradicted the burden assumption that combining caregiving with paid or voluntary work is associated with more time burden and less happiness. The result that combining caregiving with paid employment or volunteering is related to higher rates of happiness confirms the subjective well‐being assumption. It is concluded that these cross‐sectional results open ways to longitudinal research that can inform governments in the development of policies to support informal caregivers.  相似文献   
83.
BackgroundTo determine the effect of low-dose, high-pitch non-electrocardiographic (ECG)-triggered chest CT on coronary artery calcium (CAC) detection, quantification and risk stratification, compared to ECG-triggered cardiac CT.MethodsWe selected 1,000 participants from the ImaLife study, 50% with coronary calcification on cardiac CT. All participants underwent non-contrast cardiac CT followed by chest CT using third-generation dual-source technology. Reconstruction settings were equal for both acquisitions. CAC scores were determined by Agatston's method, and divided dichotomously (0, >0), and into risk categories (0, 1–99, 100–399, ≥400). We investigated the influence of heart rate and body mass index (BMI) on risk reclassification.ResultsPositive CAC scores on cardiac CT ranged from 1 to 6926 (median 39). Compared to cardiac CT, chest CT had sensitivity of 0.96 (95%CI 0.94–0.98) and specificity of 0.99 (95%CI 0.97–0.99) for CAC detection (κ = 0.95). In participants with coronary calcification on cardiac CT, CAC score on chest CT was lower than on cardiac CT (median 30 versus 40, p?0.001). Agreement in CAC-based risk strata was excellent (weighted κ = 0.95). Sixty-five cases (6.5%) were reclassified by one risk category in chest CT, with fifty-five (84.6%) shifting downward. Higher BMI resulted in higher reclassification rate (13% for BMI ≥30 versus 5.2% for BMI <30, p = 0.001), but there was no effect of heart rate.ConclusionLow-dose, high-pitch chest CT, using third-generation dual-source technology shows almost perfect agreement with cardiac CT in CAC detection and risk stratification. However, low-dose chest CT mainly underestimates the CAC score as compared to cardiac CT, and results in inaccurate risk categorization in BMI ≥30.  相似文献   
84.
To study the tumor cell autonomous processes of metastasis, an in vivo tumor metastasis model is required that excludes the involvement of the innate immune system. For this purpose we used the established syngeneic MTLn3 cell - Fischer 344 tumor model. MTLn3 cells are efficiently eradicated by NK cells in vivo. Using isolated cell systems, we provide evidence for apoptosis-induction by IL-2 activated NK cells, but not T-cells, despite the expression of MHC class I. This is largely mediated by the perforin/granzyme B pathway in MTLn3 cells in a caspase-dependent manner. Temporal in vivo depletion of NK cells by an antibody-based method, dramatically improved colonization of the lungs by MTLn3 cells, from 5 metastases in the untreated animals to 130 metastases in the NK-depleted animals. Thus, we improved the syngeneic MTLn3-Fischer 344 tumor model by temporal depletion of NK cells of which the advantages over the use of immunodeficient animals are evident.  相似文献   
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Autogenous bone graft harvesting is still commonly considered the gold standard for the reconstruction of a severely resorbed maxillary alveolar ridge; however, the preferred donor site remains a subject of debate. This study compared the morbidity of calvarial and iliac crest donor sites after harvesting. Twenty edentulous patients with an insufficient volume of maxillary bone for reliable implant placement were assigned randomly to either calvarial (n = 10) or anterior iliac crest (n = 10) bone harvesting groups. All patients underwent a maxillary sinus floor elevation procedure combined with widening of the alveolar process using buccal bone blocks. Donor site morbidity was assessed before, during, and at 1 year after the surgery through patient questionnaires, physical examination, and medical records. No perioperative complications occurred. The anterior iliac crest group reported minor postoperative pain after harvesting. The scars after calvaria harvesting were significantly longer (P = 0.003), but this was not bothersome for the group of patients. Long-term pain was negligible and satisfaction was high in both groups. Both the calvaria and anterior iliac crest are associated with low long-term donor site morbidity and high patient satisfaction. Thus, patient-centred decision-making is appropriate when selecting the preferred harvesting method for that patient.  相似文献   
88.
DEC-205 is a type I C-type lectin receptor (CLR) that is expressed on various APC subsets and has been suggested to bind necrotic and apoptotic cells. Here we study DEC-205 characteristics in plasmacytoid DCs (pDCs) obtained from healthy individuals and assess its ability to mediate antigen presentation by isolating sufficient numbers of pDCs from apheresis material obtained from stage III/IV melanoma patients. The results demonstrate that DEC-205 is expressed on human pDCs. Internalization of DEC-205 after antibody ligation is clathrin- and dynamin-dependent as it is blocked by hypertonic shock or by inhibition of dynamin activity. Antibody targeting to DEC-205 does not affect TLR-induced expression levels of co-stimulatory and MHC molecules, but clearly impairs TLR-induced IFN-α secretion by 40%. We observed that TLR-mediated signaling increases DEC-205 expression levels without affecting receptor internalization. Moreover, human pDCs retained the capacity to present antigens via DEC-205 following TLR activation.  相似文献   
89.
Atopic diseases are characterized by the presence of Th2 cells. Recent studies, in mice and man, demonstrated that allergen-specific Th2 responses can be shifted to Th0/Th1 responses. Plasmacytoid dendritic cells (pDCs) produce large amounts of type I interferons (IFNs) after stimulation of Toll Like Receptor 9 (TLR9) and are likely to play an important role in the reorientation of these Th2 cells. The expression of CD32a on the cell surface of pDCs makes this cell type attractive for targeted delivery of antigen and TLR agonists to revert Th2 responses. Therefore we sought to determine the efficacy of targeted delivery of CpG-C ODN to CD32a on the ability of human and monkey pDCs to secrete inflammatory cytokines. Here we demonstrate that targeted delivery of 3'-biotinylated CpG-C to CD32a on pDC induced phenotypical maturation as determined by CD80, CD83 and CD86 expression. Furthermore, targeting both monkey and human pDCs strongly augmented the secretion of IFNα compared to the delivery of CpG-C in an untargeted fashion (p<0.001). TLR9 induced activation hampers the ability of human pDCs to internalize CD32a. Therefore we opted for targeted delivery of CpG-ODNs to CD32a, which reduces the risk of undesired side effects of systemic TLR treatment and in addition delivers a superior signal for the activation of pDCs. This approach opens new treatment principles for allergic patients.  相似文献   
90.
Many early drug research efforts are too reductionist thereby not delivering key parameters such as kinetics and thermodynamics of target-ligand binding. A set of human D-Amino Acid Oxidase (DAAO) inhibitors 1-6 was applied to demonstrate the impact of key biophysical techniques and physicochemical methods in the differentiation of chemical entities that cannot be adequately distinguished on the basis of their normalized potency (ligand efficiency) values. The resulting biophysical and physicochemical data were related to relevant pharmacodynamic and pharmacokinetic properties. Surface Plasmon Resonance data indicated prolonged target-ligand residence times for 5 and 6 as compared to 1-4, based on the observed koff values. The Isothermal Titration Calorimetry-derived thermodynamic binding profiles of 1-6 to the DAAO enzyme revealed favorable contributions of both ΔH and ΔS to their ΔG values. Surprisingly, the thermodynamic binding profile of 3 elicited a substantially higher favorable contribution of ΔH to ΔG in comparison with the structurally closely related fused bicyclic acid 4. Molecular dynamics simulations and free energy calculations of 1, 3, and 4 led to novel insights into the thermodynamic properties of the binding process at an atomic level and in the different thermodynamic signatures of 3 and 4. The presented holistic approach is anticipated to facilitate the identification of compounds with best-in-class properties at an early research stage.  相似文献   
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