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61.
本文用同时记录两相邻空肠段的收缩活动来观察经10Gyγ线照射后小肠运动的变化,以了解照射后是否出现逆蠕动,以便进一步分析肠套叠形成的原因.结果表明,照射后两相邻肠段出现强度不一的收缩活动,并且可以产生逆蠕动;但是这种逆蠕动发生的机率是不大的.本实验未观察到逆蠕动发生的规律性.因此,逆蠕动的产生可能是照射后发生肠套叠的部分原因. 相似文献
62.
Luca Busetto Claudia Pisent Gianni Segato Francesco De Marchi Franco Favretti Mario Lise Giuliano Enzi 《Obesity surgery》1997,7(6):505-512
Objective: To evaluate the effects of a new timing strategy of band adjustment on the short-term outcome of obese women operated
with adjustable silicone gastric banding. Subjects: The outcome of 30 women without binge-eating disorder operated with laparoscopic
adjustable silicone gastric banding with a wider intraoperatory band calibration (LAP-BAND) was compared to that of 30 body
mass index-matched women without binge-eating disorder previously operated with adjustable silicone gastric banding (ASGB)
applied by laparotomy with the usual intraoperatory band calibration. The patients were evaluated 3, 6 and 12 months after
surgery. Measurements: (1) weight loss; (2) total daily energy intake; (3) percent as liquid, soft or solid food; (4) vomiting
frequency; (5) rate of postoperative percutaneous band adjustments; (6) rate of band-related complications. Results: Both
the weight loss and the daily energy intake did not differ between patients with LAP-BAND and patients with ASGB. After surgery,
the patients with LAP-BAND ate more solid food and less liquid food than the patients with ASGB. Vomiting frequency was higher
in patients with ASGB than in patients with LAP-BAND. The total number of percutaneous band adjustments was higher in women
with LAP-BAND than in women with ASGB. Band inflation because of weight stabilization was performed in six (20.0%) women with
ASGB and in 19 (63.3%) women with LAP-BAND. Neostoma stenosis occurred in one women with ASGB, but in none of the women with
LAP-BAND. One patient with LAP-BAND presented band slippage. Conclusions: The wider intraoperatory band calibration performed
in patients with LAP-BAND did not reduce the short-term efficacy of adjustable silicone gastric banding. This new timing strategy
of band adjustment required more postoperative percutaneous band inflations, but it improved the eating pattern of the patients
(low vomiting frequency and high intake of solid food). 相似文献
63.
Effects of enteral feedback inhibition on motility,luminal flow,and absorption of nutrients in proximal gut of minipigs 总被引:2,自引:0,他引:2
Andreas Huge Eckhard Weber Prof. Dr. Hans-Jörg Ehrlein 《Digestive diseases and sciences》1995,40(5):1024-1034
We wanted to clarify whether the postprandial intestinal feedback control activated by nutrients in the distal gut exerts different effects on motility, transit of digesta, and absorption of nutrients in the proximal gut. Additionally, interrelationships among motility, transit, and absorption were to be elucidated because these relationships have only been investigated in the fasted state. In five minipigs, a 150-cm segment of the proximal jejunum was isolated by two cannulas. Motility of the jejunal segment was recorded by multiple strain gauges and analyzed by computerized methods. Markers (Cr- and Cu-EDTA) were used for the measurement of the flow rate, transit time, and absorption of nutrients. After a meal, the test segment was perfused with 2 kcal/min of an elemental diet over a period of 90 min. A feedback inhibition was activated by infusion of nutrients into the midgut at rates of 1–4 kcal/min. Saline was infused as control. With increasing energy loads infused into the midgut, the motility index and the length of contraction waves decreased, whereas the incidence of stationary contractions increased, ie, the motility changed from a propulsive to a segmenting pattern. These modulations of motility were associated with a linear decrease in the flow rate and a linear increase in transit time. Flow and transit were linearly correlated with each other. Additionally, the reduction in flow rate and the delay in luminal transit were associated with a linear increase in the absorption of nutrients. However, the increase in absorption induced by the feedback mechanism was small (7.3–13.4%) compared to the marked inhibition of the motility parameters (54–64%), the flow rate (59%), and the delay of transit (5.8-fold). Feedback control primarily modulated motor patterns and luminal flow, whereas the small increase in absorption was only a side effect due to the longer contact time of the nutrients with the mucosa.The study was supported by the Deutsche Forschungsgemeinschaft, grant Eh 64/6-3. 相似文献
64.
本工作观察了乙酰胆硷(Ach)和电刺激迷走神经对0.6N HCl引起的胃粘膜出血性损伤的保护作用,发现皮下注射50μg/kg的氯化Ach和电刺激膈下迷走神经5min,可明显降低HCl引起的胃粘膜出血量,这一作用可被消炎痛及阿托品所阻断。提示这种保护作用是通过依赖于M-受体的内源性前列腺素。 相似文献
65.
门脉高压性胃病患者的胃壁血气变化 总被引:1,自引:0,他引:1
作者观测了43例门脉高压症患者股动脉血PO2、胃网膜有动静脉胃壁支血PO2、胃壁支静脉及肘静脉血pH、HCO3-和胃网膜右静脉压力,其中23例并有非出血期门脉高压性胃病。结果表明:①门脉高压症患者的股动脉血PO2低于对照组;②门脉高压症患者胃网膜右动静脉胃壁支血氧分压差低于对照组,胃网膜右静脉压力高于对照组,胃壁支静脉血pH和HCO3-低于对照组和同组肘静脉血。并有门脉高压性胃病者这些变化更为显著。提示门脉高压性胃病的发病机制在于门脉系压力增高、胃粘膜下动静脉短路开放、胃粘膜缺血缺氧和胃壁局部酸中毒。 相似文献
66.
Reduced Expression of nm23 Is Associated with Metastasis of Human Gastric Carcinomas 总被引:7,自引:0,他引:7
Reduced expression of nm23 gene is implicated in high metastatic potential In a variety of malignancies. To elucidate the role of nm23 in human gastric carcinomas, we examined loss of heterozygosity (LOH) of nm23 gene by Southern blotting, nm23 mRNA expression by Northern blotting and nm23 protein expression by Western blotting as well as immunohistochemistry in both primary and metastatic tumors. LOH of nm23 gene was found in 2 (8%) out of the 23 informative gastric carcinomas. Twenty-two (84%) out of the 26 cases expressed nm23 mRNA at higher levels in primary tumor tissue than in corresponding non-neoplastic mucosa. No obvious correlation was observed between clinico-pathological features and LOH of nm23 gene or nm23 mRNA expression. On the other hand, 52% of the gastric carcinomas showed reduction of nm23 immunoreactivity in the metastatic tumor of regional lymph nodes, as compared to the primary tumor. Interestingly, 71% of the gastric carcinomas showed weaker nm23 immunoreactivity in the liver metastasis than in the primary tumor. These results suggest that nm23 overexpression is linked with development of gastric carcinomas and the decrease in expression of nm23 participates in metastasis. 相似文献
67.
Abstract The aim was to measure the effect of gastric electrical stimulation on the frequency of canine antral pacesetter potentials (PPs), the strength of antral contractions, and the rate of gastric emptying while fasting, after feeding and with pentagastrin stimulation. Four conscious dogs with a stimulating electrode placed 10 cm proximal to the pylorus and recording electrodes and strain gauges placed 7, 5 and 3 cm proximal to the pylorus underwent myoelectric and strain gauge recordings while fasting, after feeding (250 ml 5% dextrose labelled with polyethylene glycol), and during pentagastrin infusion (0.5 μg kg?1 min?1) on four separate days. On each day, electrical stimulation was done using one of four stimulation frequencies (0, 6, 30 and 1200 stimuli per minute ***[s.p.m.]). Stimulation at 6 and 30 s.p.m. increased the fasting and fed PP frequency, whereas 1200 s.p.m. stimulation did not. Feeding decreased the maximum driven frequency, and pentagastrin increased it. Neither the motility index nor the gastric emptying rate were consistently changed by stimulation at any frequency. In conclusion, canine proximal antral stimulation at 6 and 30 s.p.m. sped PP frequency during fasting and after feeding, but stimulation over a wide range of frequencies had little effect on gastric contractions and emptying. 相似文献
68.
B. Hohenester A. Rühl O. Kelber† & M. Schemann 《Neurogastroenterology and motility》2004,16(6):765-773
Functional dyspepsia (FD) is amongst the most common functional gastrointestinal disorders. Symptomatic treatment includes the use of herbal preparations whose effects on gastric motility are unclear. The present study aimed at investigating the effects of STW 5 (Iberogast), a fixed combination of hydroethanolic herbal extracts, on gastric motility in vitro. Muscle strips from guinea-pig gastric fundus, corpus and antrum were set up in organ baths either in circular or longitudinal orientation. Addition of ethanol-free STW 5 to the organ baths (32-512 microg mL(-1)) dose-dependently evoked a sustained and reversible relaxation of circular and longitudinal fundus and corpus muscle strips without changes in phasic activity. In contrast, antral muscle strips responded to STW 5 with a significant increase in the contractile force of phasic contractions without changes in tone. All effects were resistant to tetrodotoxin (0.5 micromol L(-1)), atropine (1 micromol L(-1)), omega-conotoxin GVIA (0.5 micromol L(-1)), capsaicin (1 micromol L(-1)) or L-NAME (100 micromol L(-1)), suggesting that neither nerves nor nitric oxide pathways were involved. These data demonstrate that STW 5 profoundly alters gastric motility in a region-specific but not layer-specific manner and thus implicates Iberogast in the treatment of FD patients suffering from motility disorders with impaired fundus accommodation and/or antral hypomotility. 相似文献
69.
BACKGROUND AND AIM: Peptic ulcer disease is believed to be less common and less severe as a result of modern medical treatment. We therefore examined changes in the admission rates for patients with duodenal ulcer and gastric ulcer, both emergency (for haemorrhage, perforation or severe pain) and for elective surgery, before and since the introduction of the new advances in therapy. These admission indices reflect disease prevalence and severity. PATIENTS AND METHODS: We identified admission rates during 1972--2000 within the Trent Regional Health Authority, UK (population 4.7 million), from computerised patient information using diagnostic search codes ICD8-10 and expressed as rates per million resident population. Drug expenditure details were obtained from the Department of Health. RESULTS: Emergency admission rates as a whole changed little, a decline in the young being offset by an increase in the elderly. Haemorrhage was the most common reason (approximately 115 per million for duodenal ulcer and 87 for gastric ulcer) throughout [compared with perforation (80 and 21) and pain (90 and 68)]. In contrast, elective surgery has almost disappeared; this reduction began before the introduction of modern treatment. CONCLUSION: Emergency admission rates for duodenal and gastric ulcer for complications or severe pain have fluctuated over the last three decades but with little overall change. In contrast, elective surgery has declined dramatically, as a result of advances in treatment but also from changes in the natural history. 相似文献
70.
目的 探讨腹腔内注射OK - 4 32增强腹腔免疫功能的机制。方法 选择非炎症和非肿瘤手术患者作为实验对象 ,实验组分别于手术前 72小时、4 8小时和 2 4小时腹腔内注射 4KE的OK - 4 32。开腹后采集腹腔内巨噬细胞 ,并用人胃癌MKN1细胞作为靶细胞对巨噬细胞的癌细胞毒性进行分析。同时采集大网膜 ,对大网膜乳斑的数量和面积进行了观察分析。结果 OK - 4 32显著增加了腹腔内巨噬细胞的数量 (P <0 .0 5 )、增强了巨噬细胞的吞噬活性和酶活性 (P <0 .0 5 )、增加了NO的分泌和巨噬细胞的癌细胞毒性 (P <0 .0 5 ) ,以及大网膜乳斑的数量和面积 (P <0 .0 5 )。结论 手术前腹腔内注射OK - 4 32可以作为预防癌细胞腹腔内种植转移的有效方法。 相似文献