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Objective. Endoscopic stenting for malignant gastric outlet obstruction was chosen as the primary strategy by which to palliate this complication, which is dominated by weight loss and anorexia. Advanced upper gastrointestinal tract cancers present late and life expectancy is limited. Only smaller multicentre studies point to endoscopic stenting as superior to surgery in terms of clinical outcome and cost. Material and methods. Forty-five consecutive patients with gastric outlet obstruction as a result of advanced upper GI-tract malignancy were enrolled in accordance with the intention-to-treat principle. All patients were offered endoscopic stenting. Oral intake before and after stenting was assessed using the gastric outlet obstruction score system (GOOSS). Various lengths of duodenal Hanaro® self-expanding nitinol stents were delivered through a therapeutic endoscope. Outcome criteria were successful deployment, clinical effect, length of stay in hospital, survival, need for re-intervention and complications. Results. Forty-one patients (91%) were successfully stented. The mean pre-procedure GOOSS improved significantly from 0.39 (95% CI 0.22–0.56) to 2.29 (95% CI 2.01–2.58) after stenting (p<0.0001). Twenty-six patients (63%) improved GOOSS at least one point, whereas 5 patients (12%) did not change GOOSS at all. Mean length of hospital stay was 13 days (95% CI 9–17 days). Mean survival was 121 days (95% CI 62–181 days). Two patients (4%; numbers 6 and 19) sustained perforation without fatalities. Three patients (7%) had stent migration. Procedure-related mortality was zero. Conclusions. Palliative stenting for advanced malignant upper GI-tract tumours at a tertiary Hepato-Pancreato-Biliary Unit is a safe, feasible and effective alternative to surgical bypass with a short hospital stay and prompt improvement of food intake.  相似文献   
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An ecological epidemiological study was conducted with data obtained from an environmental dose-reconstruction study and the Arizona Birth Information Tapes. Before 1981, a portion of the city of Tucson water-distribution system was contaminated with trichloroethylene (i.e., < 5 micrograms per liter of water to 107 micrograms per liter of water). Target and comparison populations were selected with a Geographic Information System. Logistical-regression analysis revealed an association between maternal exposure to trichloroethylene via drinking water and very-low-birth-weight babies (i.e., < 1,501 grams) (odds ratio = 3.3; 95% confidence interval = 0.5, 20.6; and Wald chi-square p value = 0.2). No association was found between maternal exposure to trichloroethylene via drinking water and low birth weight or full-term low-birth-weight infants (gestational period > 35 wk and < 46 wk).  相似文献   
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We examined the vitamin D receptor genotypes (BB, Bb and bb) defined by the BsmI restriction endonuclease in relation to biochemical indices of bone metabolism in healthy Caucasian infants. We measured the serum concentrations of the carboxy-terminal propeptide of type I procollagen (PICP) and the urinary excretion of total pyridinoline, free, total and bound deoxypyridinoline, the type I collagen N-terminal and C-terminal cross-linked telopeptides. The concentrations of the urinary indices are expressed relative to creatinine. Subjects with BB genotype had the highest mean concentrations of free, total and bound deoxypyridinoline and of the N-terminal cross-linked telopeptide (PANOVA = 0.0016, 0.0004, 0.0002 and 0.0053, respectively). BB boys had a higher excretion of the C-terminal cross-linked telopeptide than the other genotypes (PANOVA = 0.0253). In a subgroup of homozygotes aged 10 (1) months, BB subjects had the highest levels of the C-terminal cross-linked telopeptide (p=0.03), and of total deoxypyridinoline (p=0.02) and pyridinoline (p=0.06) concentrations. No significant association between the vitamin D receptor genotype and PICP was found. These data suggest that there may be a contribution of the vitamin D receptor genotype to skeletal metabolism in early childhood.  相似文献   
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Park DJ  Vuong PT  de Vos S  Douer D  Koeffler HP 《Blood》2003,102(10):3727-3736
Acute promyelocytic leukemia (APL) is associated with chromosomal translocations involving retinoic acid receptor alpha (RAR alpha) and its fusion partners including promyelocytic leukemia (PML) and promyelocytic leukemia zinc finger (PLZF). Using oligonucleotide arrays, we examined changes in global gene expression mediated by the ectopic expression of either PML/RAR alpha (retinoid-sensitive) or PLZF/RAR alpha (retinoid-resistant) in U937 cells. Of more than 5000 genes analyzed, 16 genes were commonly up-regulated, and 57 genes were down-regulated by both fusion proteins suggesting their role in the APL phenotype. In our APL model, for example, TNFAIP2, TNFR2, ELF4, RAR gamma, and HoxA1 were down-regulated by both fusion proteins in the absence of retinoic acid (RA). RA strongly up-regulated these genes in PML/RAR alpha, but not in PLZF/RAR alpha expressing U937 cells. Expression studies in NB4, retinoid-resistant NB4-R2, normal human CD34+ cells, and APL patient samples strongly suggest their role in the regulation of granulocytic differentiation. Furthermore, combined treatment with tumor necrosis factor alpha (TNF alpha) and RA synergistically enhanced granulocytic differentiation in NB4 cells but not in NB4-R2 cells. Our data indicate that APL pathogenesis and retinoid-induced granulocytic differentiation of APL cells involve genes in the cell death pathway, and that cooperation between the RA and TNFalpha signaling pathways exists. Targeting both the retinoid-dependent differentiation and the cell death pathways may improve leukemic therapy, especially in retinoid-resistant acute myeloid leukemia.  相似文献   
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Event-related potential responses to oddball stimuli, including the P300 component, have been proposed as a diagnostic tool for discerning psychiatric or higher-level neural disorders from malingering, for instance in cases of unexplained visual loss. For clinical use, short recording durations and easy statistical assessment are highly desirable. With this aim, we investigated the feasibility of recording oddball responses in a fast steady-state regime. We used gratings with two possible orientations in a rapid oddball paradigm with an inter-stimulus interval of 214 ms. Six consecutive presentations of one stimulus type (frequent) were followed by a single presentation of the other (infrequent) stimulus type. Subjects were attending to the rare stimulus type. The electroencephalographic recordings were analyzed in the frequency domain. All subjects produced significant harmonic responses related to the processing of the rare stimulus, demonstrating the feasibility of the technique, with the potential of reducing recording times substantially compared to conventional slow stimulation. We furthermore found that the regularity of the occurrence of infrequent stimuli, which is necessary for frequency-domain analysis, does not per se reduce the P300 responses, as would have been expected in the framework of some hypotheses regarding the role of the P300.  相似文献   
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