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排序方式: 共有2164条查询结果,搜索用时 15 毫秒
1.
Clio Mamalaki Marianna Murdjeva Mauro Tolaini Trisha Norton Phillip Chandler Alain Townsend Elizabeth Simpson Dimitris Kioussis 《Clinical & developmental immunology》1995,4(4):299-315
Influenza nucleoprotein (NP)-specific T-cell receptor transgenic mice (F5) were crossed
with transgenic mice expressing the cognate antigenic protein under the control of the H-
2Kb promoter. Double-transgenic mice show negative selection of thymocytes at the
CD4+8+TCR10 to CD4+8+TCRhi transition stage. A few CD8 T cells, however, escape clonal
deletion, and in the peripheral lymphoid organs of these mice, they exhibit low levels of
the transgenic receptor and upregulated levels of the CD44 memory marker. Such cells do
not proliferate upon exposure to antigen stimulation in vivo or ex vivo, however, they can
develop low but detectable levels of antigen-specific cytotoxic function after stimulation
in vitro in the presence of IL-2. 相似文献
2.
Papadimitriou GN Dikeos DG Souery D Del-Favero J Massat I Avramopoulos D Blairy S Cichon S Ivezic S Kaneva R Karadima G Lilli R Milanova V Nöthen M Oruc L Rietschel M Serretti A Van Broeckhoven C Stefanis CN Mendlewicz J 《Psychiatric genetics》2003,13(4):211-220
The co-segregation in one pedigree of bipolar affective disorder with Darier's disease whose gene is on chromosome 12q23-q24.1, and findings from linkage and association studies with the neighbouring gene of phospholipase A2 (PLA2) indicate that PLA2 may be considered as a candidate gene for affective disorders. All relevant genetic association studies, however, were conducted on bipolar patients. In the present study, the possible association between the PLA2 gene and unipolar affective disorder was examined on 321 unipolar patients and 604 controls (all personally interviewed), recruited from six countries (Belgium, Bulgaria, Croatia, Germany, Greece, and Italy) participating in the European Collaborative Project on Affective Disorders. After controlling for population group and gender, one of the eight alleles of the investigated marker (allele 7) was found to be more frequent among unipolar patients with more than three major depressive episodes than among controls (P<0.01); genotypic association was also observed, under the dominant model of genetic transmission (P<0.02). In addition, presence of allele 7 was correlated with a higher frequency of depressive episodes (P<0.02). These findings suggest that structural variations at the PLA2 gene or the chromosomal region around it may confer susceptibility for unipolar affective disorder. 相似文献
3.
Sonic hedgehog guides commissural axons along the longitudinal axis of the spinal cord 总被引:2,自引:0,他引:2
Bourikas D Pekarik V Baeriswyl T Grunditz A Sadhu R Nardó M Stoeckli ET 《Nature neuroscience》2005,8(3):297-304
Dorsal commissural axons in the developing spinal cord cross the floor plate, then turn rostrally and grow along the longitudinal axis, close to the floor plate. We used a subtractive hybridization approach to identify guidance cues responsible for the rostral turn in chicken embryos. One of the candidates was the morphogen Sonic hedgehog (Shh). Silencing of the gene SHH (which encodes Shh) by in ovo RNAi during commissural axon navigation demonstrated a repulsive role in post-commissural axon guidance. This effect of Shh was not mediated by Patched (Ptc) and Smoothened (Smo), the receptors that mediate effects of Shh in morphogenesis and commissural axon growth toward the floor plate. Rather, functional in vivo studies showed that the repulsive effect of Shh on postcommissural axons was mediated by Hedgehog interacting protein (Hip). 相似文献
4.
Asymmetric collimators or heavily blocked fields with physical wedges are still encountered in daily practice. In such cases, a reliable dosimetry system is necessary to perform manual dose and monitor unit calculations in order to independently verify the calculations of commercial treatment planning systems. In this work, primary wedged off-axis ratios (POAR(w)s) that account for changes in the beam intensity along both the wedge gradient and perpendicular directions of the photon field, when asymmetric collimators are applied, were measured experimentally at specific depths. The measurements were made in phantom with an ion chamber along the wedge gradient and the perpendicular directions under 'good geometry' conditions. A consistent formalism was presented that could easily be implemented in the clinical environment as an independent verification of the calculations by a treatment planning system. The accuracy of the method was found to be dependent on the specific wedge used, off-axis distance and depth in the phantom. In our study, the accuracy was within 2% in most cases for both energies. We concluded that the primary wedged off-axis ratios when used along with open symmetric field dosimetric parameters could provide adequate accuracy for manual monitor unit calculations. 相似文献
5.
Bariatric surgery is an effective intervention for management of obesity through treating dysregulated appetite and achieving long-term weight loss maintenance. Moreover, significant changes in glucose homeostasis are observed after bariatric surgery including, in some cases, type 2 diabetes remission from the early postoperative period and postprandial hypoglycaemia. Levels of a number of gut hormones are dramatically increased from the early period after Roux-en-Y gastric bypass and sleeve gastrectomy—the two most commonly performed bariatric procedures—and they have been suggested as important mediators of the observed changes in eating behaviour and glucose homeostasis postoperatively. In this review, we summarise the current evidence from human studies on the alterations of gut hormones after bariatric surgery and their impact on clinical outcomes postoperatively. Studies which assess the role of gut hormones after bariatric surgery on food intake, hunger, satiety and glucose homeostasis through octreotide use (a non-specific inhibitor of gut hormone secretion) as well as with exendin 9–39 (a specific glucagon-like peptide-1 receptor antagonist) are reviewed. The potential use of gut hormones as biomarkers of successful outcomes of bariatric surgery is also evaluated. 相似文献
6.
7.
Iphigenia Phocas Themis Mantzavinos Dimitris Rizos Fotini Dimitriadou Katerina Arvaniti Pantelis A. Zourlas 《Journal of assisted reproduction and genetics》1992,9(3):233-237
Background Are follicles where no oocytes are retrieved empty follicles?Methods The levels of estradiol (E2), progesterone (P), testosterone (T), cortisol (F), and prolactin (PRL) of follicular fluids (FF) aspirated individually from 34 randomly selected IVF patients in whom no oocytes were recovered were compared with the respective hormone levels of FF obtained from the same patients when oocytes were retrieved. Two FF without oocytes of a 35th patient in whom no oocytes were retrieved were analyzed.Results Hormones did not differ significantly in the paired samples, while in the two FF of the 35th woman they were in agreement with cystic follicles.Conclusions It is necessary to differentiate aspirated follicles where no oocytes are retrieved from the empty follicle syndrome, which was not observed in the IVF series studied and should be rare in IVF patients. 相似文献
8.
9.
Real-time quantification of CK-19 mRNA-positive cells in peripheral blood of breast cancer patients using the lightcycler system. 总被引:10,自引:0,他引:10
10.
Herman Nys Sander Welie Tina Garanis-Papadatos Dimitris Ploumpidis 《Health care analysis》2004,12(4):329-337
The discriminatory effects of categorizing psychiatric patients into competent and incompetent, have urged lawyers, philosophers and health care professionals to seek a functional approach to capacity assessment. Dutch and English law have produced some guidelines concerning this issue. So far, most legal systems under investigation have concentrated on alternatives for informed consent by the patient in case of mental incapacity, notably substitute decision-making, intervention of a judge and advance directives. It is hard to judge the way in which the law may further adapt to a more functional assessment of capacity, because the nature of law shows that legal reforms usually take place only when new methods have been accepted by the field. This is not yet the case today. 相似文献