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11.
Oropharyngeal candidiasis (OPC), caused by Candida albicans, is the most frequent opportunistic fungal infection in human immunodeficiency virus (HIV)-positive persons. Although Th1-type CD4(+) T cells are considered important for host defense against mucosal C. albicans infections, there is a paucity of information regarding the presence and/or role of T cells in OPC lesions. In pursuit of this, initial chromophore immunohistochemical studies showed a majority of CD8(+) rather than CD4(+) cells equally distributed throughout the buccal mucosa of OPC(-) persons (HIV(-) or HIV(+)), irrespective of blood CD4(+) cell numbers. In contrast, CD8(+) cells in lesions from HIV(+) OPC(+) persons were in significantly higher numbers and concentrated at the lamina propria-epithelium interface, a considerable distance from the Candida at the outer epithelium. Dual fluorescence and confocal microscopy confirmed that the majority of CD8(+), but not CD4(+), cells were T cells by the presence or absence, respectively, of CD3 on each cell type. These results suggest that CD8(+) T cells may be important for oral host defense against OPC, especially when CD4 cell numbers are reduced, with a potential CD8 cell-specific dysfunction associated with susceptibility to OPC.  相似文献   
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Corticosteroid therapy in biliary atresia   总被引:4,自引:0,他引:4  
Sixteen patients with biliary atresia had 44 steroid courses for treatment of cholangitis or diminution of bile flow following Kasai hepatic portoenterostomy operations. A "blast" type (high dose/short duration) steroid administration was employed to potentiate the choleretic and anti-inflammatory effect. There was a significant augmentation of bile flow and a reduction in maximum temperature, serum bilirubin, and alkaline phosphatase.  相似文献   
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Emotional eating is associated with an increased risk of binge eating, eating in the absence of hunger and obesity risk. While previous studies with children and adolescents suggest that emotion regulation may be a key predictor of this dysregulated eating behavior, little is known about what other factors may be influencing the link between emotional regulation and emotional eating in adolescence. This multi-method longitudinal study (n = 138) utilized linear regression models to examine associations between childhood emotion regulation, adolescent weight status and negative body image, and emotional eating at age 17. Emotion regulation predicted adolescent emotional eating and this link was moderated by weight status (β = 1.19, p < 0.01) and negative body image (β = −0.34, p < 0.01). Higher engagement in emotional eating was predicted by lower emotional regulation scores among normal-weight teens (β = −0.46, p < 0.001) but not among overweight/obese teens (β = 0.32, p > 0.10). Higher scores on emotion regulation were significantly associated with lower emotional eating at high (β = −1.59, p < 0.001) and low (β = −1.00, p < 0.01) levels of negative body image. Engagement in emotional eating was predicted by higher negative body image among overweight/obese teens only (β = 0.70, p < 0.001). Our findings show that while better childhood emotion regulation skills are associated with lower emotional eating, weight status and negative body image influence this link and should be considered as important foci in future interventions that aim to reduce emotional eating in adolescence.  相似文献   
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Pharmacologic therapy of lipid disorders has become an established means to reduce cardiovascular morbidity and mortality. Compared to middle-aged individuals with hyperlipidemia, the use of such treatment in the elderly population has been controversial, as there is only scant data from large clinical trials that can be applied to this group. Therefore, current recommendations for specific anti-lipid drug use in older individuals must weigh each drug's potential benefits against the potential treatment risks that are inherent to this age group.  相似文献   
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Background: The K-ras oncogene is activated by point mutations at codon 12 in most patients with exocrine pancreatic cancer. Mutant-enriched polymerase chain reaction (PCR) amplification can enhance the detection of mutated K-ras. This technique was applied to patients undergoing percutaneous fine-needle aspiration (FNA) biopsy of suspect pancreatic lesions. Methods: Twenty-five patients underwent percutaneous FNA of the pancreas for cytologic and molecular analysis. After preparing cytologic smears, the 22-gauge needle and syringe used for FNA were rinsed in RPMI-1640. The specimen was centrifuged, and DNA was extracted from the supernatant and subjected to mutant-enriched PCR using appropriate mismatched primers that introduce a BstNI restriction endonuclease cleavage site at codon 12 of wild-type, but not mutant, K-ras. After digestion with BstNI, the DNA was reamplified. To increase assay sensitivity, the final five PCR cycles were completed incorporating 5 μCi of (α-32P)dCTP. The DNA was then redigested and subjected to gel electrophoresis and autoradiography. Results: The median amount of DNA retrieved per specimen was 3.33 μg. Mutant K-ras was detected as a band of 143 bps; residual wild-type DNA was seen as a 114-bp fragment. Twenty-one of 25 specimens demonstrated mutated K-ras DNA. Two patients with nondiagnostic cytology results had mutated K-ras DNA; adenocarcinoma of pancreatic origin was confirmed in both cases after pancreatectomy. Conclusion: The molecular diagnosis of pancreatic cancer through identification of mutations in K-ras can be readily performed on specimens obtained by percutaneous FNA. As aggressive multimodality management of this disease becomes more common, pretreatment analysis of molecular determinants may have greater clinical significance. Presented at the 48th Cancer Symposium of The Society of Surgical Oncology, Boston, Massachusetts, March 23–26, 1995.  相似文献   
17.
Survival after Kasai's operation for "noncorrectable" biliary atresia is influenced by (1) age, (2) large bile ducts, and (3) concentration of the bile bilirubin. Critical values are: age less than 10.5 wk, any evidence of a large bile duct, and a bile bilirubin concentration greater than 8.8 mg/100 ml. Using these 3 factors, a predictive model is able to identify a favorable group with an 89% expected 4 yr survival.  相似文献   
18.
The mode of action by which the atypical antipsychotic drug clozapine exerts its superior efficacy to ameliorate both positive and negative symptoms is still unknown. In the present in vivo electrophysiological study, we investigate the effects of haloperidol (a typical antipsychotic drug) and clozapine on ventral tegmental area (VTA) dopamine (DA) neurons in a situation of hyperdopaminergic activity in order to mimic tentatively a condition similar to that seen in schizophrenia. Increased DA transmission was induced by elevating endogenous levels of the N-methyl-D-aspartate receptor and alpha7(*) nicotinic receptor antagonist kynurenic acid (KYNA; by means of PNU 156561A, 40 mg /kg, i.v.). In control rats, i.v. administered haloperidol (0.05-0.8 mg/kg) or clozapine (1.25-10 mg/kg) was associated with increased firing rate and burst firing activity of VTA DA neurons. However, in rats displaying hyperdopaminergia (induced by elevated levels of KYNA), the effects of clozapine on VTA DA neurons were converted into pure inhibitory responses, including decrease in burst firing activity. In contrast, haloperidol still produced an excitatory action on VTA DA neurons in rats with elevated levels of endogenous brain KYNA. The results of the present study suggest that clozapine facilitates or inhibits VTA DA neurotransmission, depending on brain concentration of KYNA. Such an effect of clozapine may be related to its unique effect in also ameliorating negative symptoms of schizophrenia.  相似文献   
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