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排序方式: 共有5810条查询结果,搜索用时 156 毫秒
1.
Eglantina Idrizaj Rachele Garella Roberta Squecco Maria Caterina Baccari 《World journal of gastroenterology : WJG》2020,26(20):2472-2478
The regulation of food intake is a complex mechanism, and the hypothalamus is the main central structure implicated. In particular, the arcuate nucleus appears to be the most critical area in the integration of multiple peripheral signals.Among these signals, those originating from the white adipose tissue and the gastrointestinal tract are known to be involved in the regulation of food intake.The present paper focuses on adiponectin, an adipokine secreted by white adipose tissue, which is reported to have a role in the control of feeding by acting centrally. The recent observation that adiponectin is also able to influence gastric motility raises the question of whether this action represents an additional peripheral mechanism that concurs with the central effects of the hormone on food intake. This possibility, which represents an emerging aspect correlating the central and peripheral effects of adiponectin in the hunger-satiety cycle, is discussed in the present paper. 相似文献
2.
目的探究N6-甲基腺嘌呤(m6A)去甲基化酶ALKBH5与弱精症的相关性。方法收集精液标本30份,包括弱精症患者与健康者精液标本各15份,密度梯度离心纯化精子,使用液相色谱与质谱联用(LC-MS/MS)检测精子RNA的m6A水平,使用实时荧光定量PCR法检测ALKBH5相对表达水平。结果弱精症患者m6A水平明显高于健康者,ALKBH5相对表达水平低于健康者,差异均有统计学意义(P<0.05)。精子活动度参数相关性分析结果显示,ALKBH5相对表达水平与前向运动精子数和非前向运动精子数呈正相关(r=0.512、0.377,P<0.05),与不动精子数呈负相关(r=-0.497,P<0.05);m6A与前向运动精子数和非前向运动精子数呈负相关(r=-0.442、-0.425,P<0.05),与不动精子数呈正相关(r=0.528,P<0.05)。结论在弱精症患者中,m6A及其去甲基化酶ALKBH5与精子活动度具有相关性。 相似文献
3.
AKIKO TANAKA MASAHIRO MATSUMOTO YUJIRO HAYASHI KOJI TAKEUCHI 《Journal of gastroenterology and hepatology》2006,20(1):38-45
Background and Aim: We recently reported that cyclooxygenase (COX)-2 is upregulated in the rat small intestine after administration of indomethacin, and this may be the key to non-steroidal anti-inflammatory drug (NSAID)-induced intestinal damage. The present study investigated the mechanism for COX-2 expression induced in the rat small intestine by indomethacin, in relation with ulcerogenic processes.
Methods: Animals were given indomethacin or SC-560 p.o., and the intestinal mucosa was examined 24 h later.
Results: Indomethacin caused hemorrhagic lesions in the small intestine, accompanied with an increase in intestinal motility, bacterial invasion and inducible nitric oxide synthase (iNOS) activity, as well as the expression of COX-2 mRNA in the mucosa. Although SC-560 did not cause any damage, this agent caused intestinal hypermotility, the bacterial invasion and the upregulation of COX-2 expression. The mucosal PGE2 content was decreased by SC-560 at 3 h but recovered 12 h later, and this recovery of PGE2 was attenuated by both atropine and ampicillin, in addition to rofecoxib. The intestinal hypermotility response to indomethacin was prevented by both 16,16-dimethyl PGE2 and atropine, but not ampicillin. Yet all these agents inhibited not only the bacterial invasion but also the expression of COX-2 and iNOS activity in the intestinal mucosa following indomethacin treatment, resulting in the prevention of intestinal lesions.
Conclusion: These results suggest that COX-2 expression in the intestinal mucosa following the administration of indomethacin is associated with intestinal hypermotility and bacterial invasion. The intestinal hypermotility caused by COX-1 inhibition may be a key to COX-2 expression after administration of NSAIDs and their intestinal ulcerogenic properties. 相似文献
Methods: Animals were given indomethacin or SC-560 p.o., and the intestinal mucosa was examined 24 h later.
Results: Indomethacin caused hemorrhagic lesions in the small intestine, accompanied with an increase in intestinal motility, bacterial invasion and inducible nitric oxide synthase (iNOS) activity, as well as the expression of COX-2 mRNA in the mucosa. Although SC-560 did not cause any damage, this agent caused intestinal hypermotility, the bacterial invasion and the upregulation of COX-2 expression. The mucosal PGE
Conclusion: These results suggest that COX-2 expression in the intestinal mucosa following the administration of indomethacin is associated with intestinal hypermotility and bacterial invasion. The intestinal hypermotility caused by COX-1 inhibition may be a key to COX-2 expression after administration of NSAIDs and their intestinal ulcerogenic properties. 相似文献
4.
The differences between the postprandial mixing or propulsion and the interdigestive motility of the gastrointestinal (GI)
tract are already known. Earlier studies showed dose-dependent differences in the effects of erythromycin on interdigestive
motility. The various GI side-effects (vomiting, diarrhoea) also suggest that there are different effects of erythromycin
on the GI motility. The aim of our study was to examine postprandially the propulsive effects of different doses of erythromycin
on the movement of intraluminal contents in the upper GI tract of the rat. The animals were fasted for 24 h before the experiments
but water was given freely. The rats received 1.5 ml 1.5% methylcellulose painted with 0.05% phenol-red intragastrically (test
solution). Erythromycin(E. lactobionate) was given intravenously at doses of 0.05, 0.1, 0.25, 0.5, 1.0 and 5.0 mg/kg 15 min before the administration of a test solution.
The animals were sacrificed 20,60 and 120 min after administration of methylcellulose, when the distance between the front
of the painted intraluminal contents and the pylorus was measured and expressed as a percentage of the total length of small
intestine. The phenol-red content in the stomach and small intestine was measured spectrophotometrically and the gastric emptying
was calculated from the ratio of the measured total and intestinal phenol-red content. Our results showed that the small doses
of erythromycin (0.1 and 0.25 mg/kg) accelerated gastric emptying after 20 min but did not change significantly the propulsive
motility of upper small intestine; however, large doses of erythromycin (1.0 and 5.0 mg/kg) decreased gastric emptying and
upper GI motility after 20 and 60 min. In summary, the prokinetic action of small doses of erythromycin was demonstrated,
but its effecttime on GI motility is short and the ratio of the stimulating and inhibitory doses is 1:10.
This paper was presented at the Section of IUPHAR GI Pharmacology Symposium on ’Biochemical pharmacology as an approach to
gastrointestinal disorders (basic science to clinical perspectives)‘, October 12-14, 1995, Pécs, Hungary. 相似文献
5.
慢传输性便秘结肠阿片受体的病理生理改变 总被引:9,自引:0,他引:9
目的探讨慢传输性便秘(STC)的发病机制和病理生理改变。方法应用放射配体结合分析法,检测患者结肠mu、kappa阿片受体,观察其含量变化。结果STC患者结肠mu阿片受体的最大结合数(Bmax)和解离常数(KD)比正常对照组明显增加(Bmax400.950比96.304pmol,KD431.314比179.839pmol);kappa阿片受体含量检测亦有类似结果(Bmax:375.073比45.264pmol,KD485.407比141.016pmol)。结论STC患者阿片受体含量增加,内源性阿片肽活性增加。提示采用阿片受体拮抗剂可能是治疗STC的一个新途径。 相似文献
6.
r. s. choung n. j. talley j. peterson m. camilleri d. burton w. s. harmsen † & a. r. zinsmeister † 《Neurogastroenterology and motility》2007,19(3):180-187
Itopride, a dopamine D2 antagonist and acetylcholinesterase inhibitor, significantly improved symptoms in patients with functional dyspepsia in one phase II randomized trial. However, the mechanisms by which itopride may improve symptoms are unknown. We aimed to compare the effects of two doses of itopride and placebo on gastric volumes, gastric emptying, small bowel transit and satiation in female and male healthy volunteers. Randomized, double-blind, placebo-controlled study evaluated gastric function before and after 7 days of itopride 100 mg (n = 16) or 200 mg (n = 15) or placebo (n = 15) t.i.d. Validated methods were used to study gastric accommodation (single photon emission computed tomography), gastric emptying and orocecal transit and satiation postnutrient challenge. The three arms were comparable with regard to age, gender and body mass index. There were no statistically significant effects of itopride on gastric emptying, orocecal transit, fasting gastric volume, maximum tolerated volume or aggregate symptom score with nutrient drink challenge. Postprandial (PP) change in gastric volume differed in the three groups (P = 0.019): 625[+/-28 (SEM)], 555(+/-26) and 512(+/-33) in placebo, itopride 100 and 200 mg groups, respectively. In healthy subjects, itopride reduced total PP gastric volume without accelerating gastric emptying or significantly altering gastric motor and sensory function in healthy individuals. 相似文献
7.
m. fox † r. sweis † t. wong † & a. anggiansah 《Neurogastroenterology and motility》2007,19(10):798-803
Oesophageal spasm presents with dysphagia and chest pain. Current treatments are limited by poor efficacy and side effects. Studies in health and oesophageal dysmotility show that sildenafil reduces peristaltic pressure and velocity; however the clinical efficacy and tolerability in symptomatic oesophageal spasm remains uncertain. We provided open-label sildenafil treatment to two patients with severe, treatment resistant symptoms associated with oesophageal spasm. The effects of sildenafil on oesophageal function and symptoms were documented by high resolution manometry (HRM). Patients were followed up to assess the efficacy of maintenance treatment with sildenafil b.i.d. HRM revealed focal and diffuse spasm in the smooth muscle oesophagus that were associated with symptoms in both cases, especially on swallowing solids. Lower oesophageal sphincter function was normal. A therapeutic trial of 25-50 mg sildenafil suppressed oesophageal contraction almost completely for water swallows; however effective, coordinated peristalsis returned with reduced frequency of spasm for solid swallows. Dysphagia and chest pain resolved during the therapeutic trial and efficacy was maintained on maintenance treatment with 25-50 mg sildenafil b.i.d. without troublesome side effects. This report shows that sildenafil can improve oesophageal function and relieve dysphagia and chest pain in patients with oesophageal spasm in whom other treatments have failed. 相似文献
8.
EVA ÅKERLÖF B. FREDRICSON O. GUSTAFSSON A. LUNDIN† N. O. LUNELL L. NYLUND L. ROSENBORG Å. POUSETTE 《International journal of andrology》1987,10(5):663-669
Two methods of separating human sperm were compared using twenty-two semen samples. The sperm were separated by a swim-up technique or by self-migration on a Percoll gradient followed by medium change. After separation, the sperm obtained were assessed for progressive motility, ATP content, energy charge index ([ATP + 0.5 ADP]/[ATP + ADP + AMP]) and morphology. In general, and especially for semen samples containing less than 20 X 10(6) sperm/ml, separation by Percoll gradient selected sperm that were superior to those separated by the swim-up technique. The relatively high energy charge index (greater than 0.8) showed that the sperm tolerated the separation conditions well. It is suggested that self-migration on a Percoll gradient should prove useful for obtaining sperm of high quality. 相似文献
9.
10.
Chronic intestinal pseudo-obstruction: manifestations, natural history and management 总被引:2,自引:0,他引:2
v. stanghellini r. f. cogliandro r. de giorgio g. barbara b. salvioli & r. corinaldesi 《Neurogastroenterology and motility》2007,19(6):440-452
Chronic intestinal pseudo-obstruction (CIPO) is a rare pathological condition characterized by a marked derangement of gut propulsive motility mimicking mechanical obstruction, in the absence of any lesion occluding the gut lumen. This disease is often associated with a disabling and potentially life-threatening complications and is still too often unrecognized even in referral centres. As a result, patients receive neither appropriate care nor recognition of their severe health condition. Medical and surgical therapies are often unsatisfactory and long-term outcome turns out to be poor in the vast majority of cases. This article focuses on the main clinical features, the management and long-term outcome of patients affected by CIPO, with particular emphasis on those aspects which remain a matter of debate. 相似文献