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排序方式: 共有422条查询结果,搜索用时 15 毫秒
91.
Talley NJ Venables TL Green JR Armstrong D O'Kane KP Giaffer M Bardhan KD Carlsson RG Chen S Hasselgren GS 《European journal of gastroenterology & hepatology》2002,14(8):857-863
BACKGROUND: On-demand therapy may offer an effective approach to the long-term management of gastro-oesophageal reflux disease (GORD) without oesophagitis. AIM: To examine the efficacy of the novel proton pump inhibitor esomeprazole as on-demand therapy in endoscopy-negative GORD. PATIENTS AND METHODS: Endoscopy-negative GORD patients who achieved complete resolution of heartburn after short-term esomeprazole or omeprazole treatment (n = 721) were randomized to esomeprazole 20 mg (n = 282), 40 mg (n = 293) or placebo (n = 146) on demand (maximum one dose/day) for 6 months. The primary and secondary efficacy endpoints were time to study discontinuation due to (i) unwillingness to continue and (ii) inadequate control of heartburn, respectively. RESULTS: Both doses of esomeprazole were more effective than placebo. During the 6-month period, 42% of placebo recipients discontinued treatment due to unwillingness to continue, compared with 8% and 11% of esomeprazole 20 mg and 40 mg recipients, respectively. Overall, more patients treated with esomeprazole were free from gastrointestinal symptoms after 6 months of on-demand therapy. CONCLUSIONS: Esomeprazole 20 mg was superior to placebo for on-demand treatment of GORD; a higher dose did not confer additional clinical benefit. Over 90% of patients were willing to continue on-demand treatment with esomeprazole 20 mg over a 6-month period. 相似文献
92.
BACKGROUND AND AIMS: One of the key components of inflammation is changes in vascular structure and function. This suggests that the microcirculation may be a key target of Helicobacter pylori released factors. It has previously been shown in vivo that pooled H pylori extracts from duodenal ulcer/gastritis patients induce platelet aggregation but no leucocyte activation within rat gastric mucosal microcirculation (GMMC). However, infection with strains associated with ulcer disease as compared with gastritis may exert greater effects on the microcirculation. This study used fluorescent in vivo microscopy to determine the acute effects of extracts of genotypically different H pylori strains on the GMMC. METHODS: Three H pylori extracts, with different cagA and VacA toxigenic status, were individually administered to the gastric mucosa of anaesthetised Wistar rats. The mucosal surface was visualised via an incision made in the exteriorised stomach. Fluoroscein isothiocyanate conjugated to bovine serum albumin (FITC-BSA) or acridine orange was used to quantify macromolecular leak (MML) and leucocyte/platelet activity respectively for 120 minutes. Changes in capillary and post-capillary venule (PCV) diameters were also monitored. RESULTS: The cagA(+) VacA toxigenic strain 60190 induced significant and sustained MML by five minutes (p<0.01). Transient and less leakage was observed with its isogenic VacA(-) mutant and other non-toxigenic strains regardless of cagA status. Significant increases in leucocyte adhesion (p<0.05), platelet aggregation (p<0.05), and PCV vasoconstriction (p<0.05) were only observed with the cag A(+) and toxigenic strain. CONCLUSION: Extracts of H pylori are capable of inducing marked disturbances within the rat GMMC. These disturbances seem to be dependent on the production of an active vacuolating cytotoxin. Varying effects on the GMMC may explain the clinically diverse outcomes associated with genotypically different strains. 相似文献
93.
Mechanisms of Helicobacter pylori-Induced Rat Gastric Mucosal Microcirculatory Disturbances In Vivo 总被引:2,自引:0,他引:2
The exact mechanisms by which Helicobacter pylori infection results in gastric mucosal injury are unclear. However, it has been demonstrated that surface protein extracts of the bacterium can induce a number of disturbances within the rat gastric mucosal microcirculation, including platelet aggregation and macromolecular leakage (MML) of labeled albumin. This study aimed to determine the mechanisms involved in inducing these events using the technique of fluorescent in vivo microscopy. Male Wistar rats were pretreated with either ketotifen, a mast cell stabilizer (1 mg/kg), pyrilamine, an H1-receptor antagonist (30 mg/kg), hexanolamine-PAF, a PAF-receptor antagonist (10 g/kg), l-arginine, the nitric oxide precursor (300 mg/kg) or vehicle, saline. Then 0.5 ml of H. pylori extract was administered to the exteriorized gastric mucosa of the anesthetized rat. Alterations in fluorescein-labeled albumin leak, vessel diameters, and acridine red-labeled leukocyte and platelet activity were determined over a 2-hr period. Saline pretreated animals demonstrated significant MML with a peak at 5 min (11%, P < 0.02). This was prevented with ketotifen and pyrilamine, but not with hexanolamine-PAF (17.5%, P < 0.05) and l-arginine (13%, P < 0.05). Significant numbers of platelet emboli and thrombi were observed within mucosal capillaries and postcapillary venules with vehicle pretreatment; this was prevented with hexanolamine-PAF and l-arginine, but not with ketotifen and pyrilamine. In conclusion, these studies demonstrate that more than one mediator is involved in inducing the rat gastric mucosal microcirculatory disturbances associated with H. pylori administration. Mast cells and histamine are linked to MML, with PAF, probably not derived from mast cells, involved in platelet activation. 相似文献
94.
Mönnikes H Bardhan KD Stanghellini V Berghöfer P Bethke TD Armstrong D 《Digestion》2004,69(4):238-244
BACKGROUND/AIMS: Evaluation of the response of gastroesophageal reflux disease (GERD) symptoms to treatment would be facilitated by a brief, valid, reliable and responsive, self-assessed GERD-sensitive scale. We therefore developed the Reflux Questionnaire (ReQuest). This publication describes the psychometric evaluation and validation of ReQuest. METHODS: This second phase of development was based on data from a clinical trial of patients with erosive GERD who received pantoprazole 20 or 40 mg daily for 28 days and completed weekly the long, and daily the short version of ReQuest. The psychometric analyses of ReQuest included internal consistency, test-retest reliability and responsiveness. Construct validity was evaluated by comparison with the Gastrointestinal Symptom Rating Scale (GSRS) and the Psychological General Well-Being (PGWB) scale. RESULTS: Validation of ReQuest indicated very high internal consistency (Cronbach's alpha = 0.90) and test-retest reliability (intraclass correlation coefficient 0.94 (long-long) and 0.86 (short-short)). This was also the case for the two subscales ReQuest-GI and ReQuest-WSO with Cronbach's alpha coefficients of 0.84 and 0.81. Responsiveness was high with a responsiveness index of >0.8 at day 28. Construct validity was good. CONCLUSION: ReQuest is a highly reliable, valid and responsive self-assessment tool for evaluating treatment response in patients with erosive GERD, and can be applied daily. 相似文献
95.
All-trans retinoic acid reverses phorbol ester resistance in a human myeloid leukemia cell line 总被引:1,自引:0,他引:1
Yang KD; Mizobuchi T; Kharbanda SM; Datta R; Huberman E; Kufe DW; Stone RM 《Blood》1994,83(2):490-496
96.
BACKGROUND AND AIM: We have documented the changing pattern of peptic ulcer disease in our centre in the last quarter of the 20th century and speculate on the reasons thereof. PATIENTS AND METHODS: The profile of peptic ulcer disease patients presenting newly to our centre (population 250,000) from 1977 to 2001 was examined. All patients were prospectively followed and detailed records kept. Results are presented in 5-year periods. RESULTS: Seven thousand five hundred and ninety new peptic ulcer disease patients (5564 duodenal ulcer+2026 gastric ulcer) were seen, peaking in 1982-1986 but declining thereafter, and with a falling male preponderance. Patients with gastric ulcer were older than those with duodenal ulcer; were older than duodenal ulcer, the mean age of both increased over time and the age gap from the general population widened. The numbers presenting with perforation changed little but haemorrhage increased, particularly amongst the elderly. Ulcers refractory to H2 receptor antagonists declined even before proton pump inhibitors were introduced. Elective surgery, already declining before H2 receptor antagonists, had virtually disappeared by 1992-1996. DISCUSSION AND CONCLUSION: Peptic ulcer disease affects an older population, an increasing proportion of whom present with haemorrhage. Refractoriness to H2 receptor antagonists and the need for elective operation was declining even before the emergence of modern treatment. We suggest the changes observed result not only from modern therapy but also substantially from a changing natural history. 相似文献
97.
BACKGROUND & AIMS: The majority of patients with celiac sprue experience diarrhea before diagnosis. There have been no studies of the prevalence or causes of chronic diarrhea in these patients after treatment with a gluten-free diet. METHODS: Seventy-eight patients with celiac sprue (59 women and 19 men) treated with a gluten-free diet for at least 12 months were surveyed about their bowel habits. Those with chronic diarrhea, defined as passage of loose stools three or more times per week for 6 months, underwent an extensive diagnostic evaluation to determine its cause. RESULTS: Sixty-two of the 78 patients (79%) experienced diarrhea before treatment, and 13 (17%) had chronic diarrhea (of lesser severity) after treatment. The causes of diarrhea in 11 patients consenting to this study were microscopic colitis, steatorrhea secondary to exocrine pancreatic insufficiency, dietary lactose or fructose malabsorption, anal sphincter dysfunction causing fecal incontinence, and the irritable bowel syndrome. Only 1 patient had antigliadin antibodies detected in serum or small intestinal villous atrophy. CONCLUSIONS: After treatment of celiac sprue with a gluten-free diet, chronic diarrhea persists in a substantial percentage of patients. Although ongoing gluten ingestion is one possible cause, other causes may be more frequent. Therefore, diagnostic investigation of diarrhea in celiac sprue after treatment seems warranted. (Gastroenterology 1997 Jun;112(6):1830-8) 相似文献
98.
BACKGROUND AND AIM: This prospective cohort observational study, set in a district hospital, presents our experience (1976-1993) of duodenal ulcer refractory to histamine H2 receptor antagonists (defined as not healed after 3 months' treatment) and comments on onset, outcome and spontaneous decline. METHODS: Patients were treated mainly with cimetidine, the dose being titrated (up to 3.2 g daily) according to response, and followed by serial check endoscopy and clinical assessment. RESULTS: A total of 782 of the 4032 duodenal ulcer patients seen (19%) were refractory; the incidence declined over time: 1976-1978: 124/379 (33%); 1979-1983: 390/1240 (31%); 1984-1988: 190/1295 (15%); 1989-1993: 78/1118 (7%). A total of 344 were refractory for the first time on their first healing course and 174 on their second. Healing was achieved in two-thirds after a mean of 7 months' treatment with cimetidine 1 g; treatment for 12-18 months with higher doses was needed in the remainder. Relapse occurred in up to three-quarters of patients despite maintenance cimetidine up to 3 g daily. Eventually 47 patients were operated upon but good results (i.e., no ulcer, no symptoms) were achieved in only 11. CONCLUSION: Refractoriness was common until recently. Its incidence has declined dramatically, the fall preceding the newer more powerful treatment with proton pump inhibitors and with Helicobacter pylori eradication. We suggest this phenomenon is a modern example of a spontaneous change in the natural history of the disease. 相似文献
99.
100.
NJ Gogtay KD Kamtekar SS Dalvi SS Mehta AR Chogle U Aigal NA Kshirsagar 《BMC infectious diseases》2006,6(1):16-4