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121.
The relative effectiveness of intermittent infusions and primed continuous infusions of cimetidine in the maintenance of intragastric pH greater than or equal to 4.0 was evaluated in a double-blind crossover trial in 26 patients who had active or healed gastroduodenal ulcers. During the intermittent phase, each patient received 300 mg cimetidine intravenously every 6 hours. During the continuous infusion phase, each patient was given a continuous infusion of 37.5 mg cimetidine per hour, preceded by a priming dose of 300 mg cimetidine that was given for 15 minutes. Intragastric pH was monitored continuously. During the last 12 hours of the study, the continuous infusion regimen provided 20% more time in which the pH was more [corrected] than 4.0 with 25% less medication than did the intermittent infusion regimen.  相似文献   
122.
A cross-over design study was used to examine the metabolic consequences of enteral feeding for 48 to 96 hours with either a branched-chain amino acid (BCAA)-enriched (44% BCAA) or a conventional egg protein formulation in 12 severely burned adult patients. A stable isotope labeled leucine (L-1-13C-leucine) tracer approach was used to measure leucine flux and oxidation and to estimate rates of whole body protein synthesis and breakdown. Additionally, 15N2-urea and 6,6-2H-glucose were administered to assess the status of urea and glucose kinetics with these two nutritional treatments. Average patient age was 54 years, and average burn surface area was 36%. Studies were conducted at an average of 25 days postburn. Leucine flux and oxidation were significantly (p less than 0.01, by paired t-test) elevated with BCAA feeding as compared to the egg protein formulation. However, there were no significant differences in the rates of leucine incorporation into, or release from, proteins (p greater than 0.05) between the two dietary periods. Mean rates of body protein synthesis and breakdown for each diet were about twice the rates reported for healthy young adults. Apparent nitrogen balance measurements were not statistically different (p greater than 0.1) between the two diet periods. Furthermore, urea and glucose kinetics failed to show significant differences between the two diet periods. It appears from these results that the major consequences of increased intake of leucine from the BCAA formula is an enhanced rate of leucine oxidation. In conclusion, (1) the availability of BCAAs is not rate-limiting for enhanced protein synthesis in burn patients, and (2) the use of enriched BCAA formulas in burn therapy does not appear to offer advantages over a routinely used enteral egg protein formula, at least based on the present determinations.  相似文献   
123.
白细胞介素-13功能研究进展   总被引:5,自引:0,他引:5  
白细胞介素-13主要由活化的Th2(CD4^ )细胞分泌,诱导单核巨噬细胞分化及延长寿命;促进MHC-Ⅱ,CD23表达;抑制炎性和趋化因子产生;诱导B细胞增殖,活化,刺激IgM,IgG的产生和重链的转换;使血管细胞粘附分子-1表达;抑制人类免疫缺陷病毒(HIV)复制;间接诱导巨噬细胞和NK细胞参与抗肿瘤作用。在变态反应性疾病和哮喘中引起呼吸道高反应性,嗜酸粒细胞性炎症,粘液分泌过多,基膜纤维化等,其受体是与IL-4Rα形成功能复合体而发挥作用。IL-13信号转导途径除了JAK/STAT6以外,尚有IRS-1,Fes,磷酸激酶,BCL-6/SOCS等途径。  相似文献   
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Forty-seven patients aged more than 75 years with acute pancreatitis were studied. The most common cause of acute pancreatitis was biliary tract stones. The clinical presentation and severity of the disease as judged by the number of poor prognostic factors were not different from the group of patients aged less than 75 years. The mortality rate in the older group was thrice that of the younger group (21.3% versus 7.24%). The higher mortality rate was explained by a higher incidence of deaths related to complications of biliary stones and coincidental diseases. Significantly more aged patients with mild disease died, indicating the limitation of predictive ability of the scoring system in acute pancreatitis of the aged.  相似文献   
126.
Influence of age on the mortality from acute pancreatitis   总被引:6,自引:0,他引:6  
The influence of age on the mortality rate of 268 patients with acute pancreatitis was studied. The hospital mortality rate for patients aged below 50 years was 5.9 per cent. The figure increased to 21.3 per cent in patients aged over 75; the high mortality was accounted for by a higher incidence of deaths related to concomitant medical or surgical diseases in the same hospital admission rather than to complications resulting directly from the pathological process of acute pancreatitis. When only deaths due to complications of acute pancreatitis were analysed, the mortality rate was not significantly different between the young and elderly groups. Moreover, the complication rate and the proportion of patients having severe disease (judged by the number of prognostic signs) were not higher in the elderly. Thus acute pancreatitis was intrinsically not more serious were it not for the presence of concomitant diseases with advanced age.  相似文献   
127.
In situ hybridization of prostate-specific antigen mRNA in human prostate.   总被引:4,自引:0,他引:4  
Prostate-specific antigen (PSA) mRNA was detected by in situ hybridization utilizing a 428 base pair [35S]-labelled cDNA probe from the 3' noncoding region of the PSA gene. Thirty six fresh surgical specimens were collected from patients undergoing radical retropubic prostatectomy for carcinoma of the prostate. Quantitative analysis of the levels of PSA mRNA in both the benign and malignant tissues was performed using an IBAS 2000 Image Analysis System. The results of this study demonstrated that there is a significant decrease in the expression of PSA mRNA in the carcinoma tissue when compared to the benign epithelium. The average binding (number of silver grains/1 x 10(4) microns. 2) for 20 specimens of malignant epithelium was 475 +/- 161 and 586 +/- 140 for 16 specimens of benign epithelium (p less than 0.05). Eleven patients had both benign and malignant tissue from the same surgical specimen available for study. From these paired specimens, the PSA mRNA expression was also significantly reduced in the malignant epithelium when compared to the benign epithelium, 445 +/- 162 and 588 +/- 135 respectively (p less than 0.005). The PSA protein was detected using a monoclonal antibody to PSA with an immunohistochemical staining technique. The PSA protein expression paralleled the expression of the PSA mRNA in the majority of the tissue sections. Many of the tumor specimens showed a heterogeneous expression of PSA, whereas all of the benign epithelium had a uniform high level of PSA expression. In conclusion, PSA mRNA and protein are located only within the glandular epithelial tissue, the expression of PSA protein parallels that of the PSA mRNA, and both the PSA protein and PSA mRNA are significantly decreased in the malignant epithelium when compared to benign prostatic epithelium.  相似文献   
128.
Sonographic findings in 16 cases of Krukenberg tumor from gastric carcinoma were analyzed. The patients' ages ranged from 25 to 52 years (mean 42 years). The tumor involved both ovaries in 14 patients with asymmetrical masses in 9 of 14 cases. Ascites was noted in 15 cases. Echogenicity of the tumor varied from solid to predominantly cystic: solid in 8, mixed in 6, and predominantly cystic in 2 cases. Solid masses tended to be smaller than mixed or cystic masses. The primary gastric carcinoma had been diagnosed before emergence of the tumors in only 7 cases. The findings suggest that in relatively young patients with ovarian mass, particularly bilateral tumors, careful evaluation for gastrointestinal tract involvement should be done.  相似文献   
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