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Burkitt’s lymphoma is a high-grade, rapidly growing B-cell neoplasm. It is recognized by its aggressive course, brief median survival, and low rates of long-term survival. The authors discuss the case of a patient who acutely presented with intraabdominal complications from a new onset of Burkitt’s lymphoma. The clinical and pathological features, staging, treatment options, and survival data are reviewed. In addition, the role of surgical intervention is carefully analyzed.  相似文献   
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Summary Slower drug absorption at night can leave residual drug from an evening dose of a sustained-release product remaining to be absorbed at the time of the next morning's dose, thereby giving higher plasma concentrations of the drug during the day than the night.When a capsule product releasing theophylline over 12 h after a morning dose was given repetitively at 8 a.m. and 8 p.m. for 4 days, daytime plasma concentrations from 4 h to 8 h after the dose were about 40% greater than corresponding night-time concentrations, and the mean steady-state concentration during the night-time interval was only 81% of that during the daytime interval.Altering the regimen to one capsule at 12 noon and one at 10 p.m. eliminated all significant differences between a.m. and corresponding p.m. plasma concentrations of theophylline and between the mean steady-state concentrations for each of the interdose intervals within a day.  相似文献   
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Role of Natural Killer Cell Subsets in Cardiac Allograft Rejection   总被引:2,自引:0,他引:2  
To achieve donor-specific immune tolerance to allogeneic organ transplants, it is imperative to understand the cell types involved in acute allograft rejection. In wild-type mice, CD4(+) T cells are necessary and sufficient for acute rejection of cardiac allografts. However, when T-cell responses are suboptimal, such as in mice treated with costimulation-targeting agents or in CD28-deficient mice, and perhaps in transplanted patients taking immunosuppressive drugs, the participation of other lymphocytes such as CD8(+) T cells and NK1.1(+) cells becomes apparent. We found that host NK but not NKT cells were required for cardiac rejection. Ly49G2(+) NK cells suppressed rejection, whereas a subset of NK cells lacking inhibitory Ly49 receptors for donor MHC class I molecules was sufficient to promote rejection. Notably, rejection was independent of the activating receptors Ly49D and NKG2D. Finally, our experiments supported a mechanism by which NK cells promote expansion and effector function of alloreactive T cells. Thus, therapies aimed at specific subsets of NK cells may facilitate transplantation tolerance in settings of impaired T-cell function.  相似文献   
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Previous studies have revealed a small number of hippocampal interneurons immunoreactive for choline acetyltransferase, the acetylcholine-synthesizing enzyme. It remained an open question, however, whether these neurons represented a subgroup of inhibitory GABAergic neurons co-localizing acetylcholine. In this study, we have combined immunocytochemistry for choline acetyltransferase and in situ hybridization for glutamate decarboxylase messenger RNA, the GABA-synthesizing enzyme. None of the choline acetyltransferase-immunoreactive neurons in the various layers of the hippocampus proper and fascia dentata were found to co-localize glutamate decarboxylase messenger RNA. The lack of an in situ hybridization signal in these neurons is unlikely to result from the combination of the two labeling techniques. When combining in situ hybridization for glutamate decarboxylase messenger RNA with immunostaining for parvalbumin, a calcium-binding protein expressed by many GABAergic hippocampal interneurons, numerous double-labeled cells were observed. These data provide neurochemical evidence for the existence of non-GABAergic, supposedly cholinergic non-principal cells in the hippocampus.  相似文献   
8.
Loss of genetic material from chromosome arm 8p occurs frequently in human breast carcinomas, consistent with this region of the genome harboring one or more tumor suppressor genes (TSGs). We used the complementary techniques of microsatellite-based LOH, high-density FISH, and conventional CGH on 6 breast cancer cell lines (MCF7, SKBR3, T47D, MDA MB453, BT549, and BT474) to investigate the molecular cytogenetic changes occurring on chromosome 8 during tumorigenesis, with particular emphasis on 6 potential TSGs on 8p. We identified multiple alterations of chromosome 8, including partial or complete deletion of 8p or 8q, duplication of 8q, and isochromosome 8q. The detailed FISH analysis showed several complex rearrangements of 8p with differing breakpoints of varying proximity to the genes of interest. High rates of LOH were observed at markers adjacent to or within PCM1, DUSP4/MKP2, NKX3A, and DLC1, supporting their status as candidate TSGs. Due to the complex ploidy status of these cell lines, relative loss of 8p material detected by CGH did not always correlate with microsatellite-based LOH results. These results extend our understanding of the mechanisms accompanying the dysregulation of candidate tumor suppressor loci on chromosome arm 8p, and identify appropriate cellular systems for further investigation of their biological properties.  相似文献   
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(1) Background: Whey protein lowers postprandial blood glucose in health and type 2 diabetes, by stimulating insulin and incretin hormone secretion and slowing gastric emptying. The branched-chain amino acids, leucine, isoleucine and valine, abundant in whey, may mediate the glucoregulatory effects of whey. We investigated the comparative effects of intragastric administration of leucine, isoleucine and valine on the plasma glucose, C-peptide and glucagon responses to and gastric emptying of a mixed-nutrient drink in healthy men. (2) Methods: 15 healthy men (27 ± 3 y) received, on four separate occasions, in double-blind, randomised fashion, either 10 g of leucine, 10 g of isoleucine, 10 g of valine or control, intragastrically, 30 min before a mixed-nutrient drink. Plasma glucose, C-peptide and glucagon concentrations were measured before, and for 2 h following, the drink. Gastric emptying of the drink was quantified using 13C-acetate breath-testing. (3) Results: Amino acids alone did not affect plasma glucose or C-peptide, while isoleucine and valine, but not leucine, stimulated glucagon (p < 0.05), compared with control. After the drink, isoleucine and leucine reduced peak plasma glucose compared with both control and valine (all p < 0.05). Neither amino acid affected early (t = 0–30 min) postprandial C-peptide or glucagon. While there was no effect on overall gastric emptying, plasma glucose at t = 30 min correlated with early gastric emptying (p < 0.05). (4) Conclusion: In healthy individuals, leucine and isoleucine lower postprandial blood glucose, at least in part by slowing gastric emptying, while valine does not appear to have an effect, possibly due to glucagon stimulation.  相似文献   
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Lasers in Medical Science - Treatment of cutaneous leishmaniasis (CL) continues to be a health concern, and alternative therapies with fewer side effects are substantially needed. This study aimed...  相似文献   
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