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91.
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
92.
女性膀胱颈部梗阻的诊断与治疗 总被引:17,自引:0,他引:17
为探讨女性膀胱颈部梗阻的病因、诊断及治疗方法。总结1981年5月~1996年6月收治女性膀胱颈部梗阻病例32例。29例经手术治疗,其中2例行膀胱颈YV成形术,27例经尿道膀胱颈部后唇切除术,效果满意。结果认为,女性膀胱颈部梗阻病因为纤维组织增生和慢性炎症所致;尿流率检查是客观评价排尿状况的指标;膀胱镜检查为可靠的诊断手段;经尿道膀胱颈部后唇切除为有效的治疗方法。 相似文献
93.
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
94.
Pharmaceutical Research - 相似文献
95.
The in vitro permeabilities of Caco-2 monolayers and permeabilities in tissue sections from colon of monkey, rabbit, and dog were compared using a series of compounds. The selected compounds differed in their physicochemical properties, such as octanol/water partition coefficient, water solubility, and molecular weight. Their structure included steroids, carboxylic acids, xanthins, alcohols, and polyethylene glycols. A linear permeability relationship was established between Caco-2 and colon tissue from both rabbit and monkey. The results suggest that Caco-2 is twice as permeable as rabbit and five times as permeable as monkey colon. However, no clear relationship could be established between Caco-2 monolayers and dog colon permeability. A relationship between permeability in Caco-2 monolayers and human absorption was found. The results suggest that within certain limits, permeability of Caco-2 monolayers may be used as a predictive tool to estimate human drug absorption. 相似文献
96.
Maria P. Panozzo Carlo Fabris Daniela Basso Giuseppe Del Favero Aldo Infantino Attilio Cecchetto Mario Plebani Remo Naccarato 《Clinical and experimental pharmacology & physiology》1993,20(3):185-191
1. The authors investigated the effect of two extrahepatic cholestasis models (one by bile duct ligation and the other by choledocho-jugular fistula) on the hepatic clearance of horseradish peroxidase in male Sprague-Dawley rats divided into four groups. 2. In groups A (n = 5 rats) and B (n = 5), bile duct ligation was performed, while a choledocho-jugular fistula was created in groups C (n = 5) and D (n= 7). A 10 mg intravenous bolus of horseradish peroxidase was injected after 24 h (groups A and C), 48 h (groups B and D) or 1 h (Group E; five sham-operated rats). Serum and bile samples were then serially collected for 2 h. 3. In all groups, serum horseradish peroxidase levels increased soon after injection and then rapidly decreased, the curves being similar. Biliary excretion increased for 30 min and then slowly decreased. The highest horseradish peroxidase biliary concentrations and outputs were found in Group B followed by Group A; both groups had significantly higher levels than Group E. No difference was found between horseradish peroxidase biliary excretion of groups C and D and that of sham-operated rats. 4. When each group was considered separately, sampling times correlated with the corresponding ratios of bile/ plasma HRP. Significant differences were found between the relative slopes of groups A, B and E, but not between those of groups C, D and E. 5. In conclusion, bile duct obstruction greatly affects the plasma-bile transfer of fluid phase markers, such as horseradish peroxidase, while single retention, caused by choledocho-jugular fistula, has no influence. The increased biliary hyperpressure related to the duration of cholestasis may account for the degree of horseradish peroxidase transfer which, in turn, probably depends on an enhanced paracellular passage. 相似文献
97.
Paediatric dacryocystorhinostomy 总被引:1,自引:0,他引:1
KN Hakin FRCS FRCOphth TJ Sullivan FRACO FRACS A Sharma FCOphth † RAN Welham FRCS FCOphth † 《Clinical & experimental ophthalmology》1994,22(4):231-235
Of 258 cases of dacryocystorhinostomy performed on children in the period September 1981 to September 1991, 130 were for simple, unresolved congenital nasolacrimal duct obstruction. Other indications for surgery included punctal agenesis, lacrimal fistula, post-traumatic and post-inflammatory canalicular obstruction. Of 177 children without canalicular pathology, 171 (96%) were relieved of symptoms with one operation, without canalicular intubation. Of 81 cases with canalicular disease, 55 of 70 (79%) who underwent DCR plus canalicular intubation, and 10 of 11 who underwent DCR plus Lester-Jones tube, were substantially improved with one operation. No child required peroperative or postoperative blood transfusion. Dacryocystorhinostomy in childhood, in experienced surgical hands, is a safe procedure, achieving relief of symptoms in most cases, particularly in the absence of canalicular disease. 相似文献
98.
Intestinal intraepithelial lymphocytes (iIEL) are primarily CD8 cells and most of them have a CD28? phenotype, the phenotype of effector cytotoxic T cells. We asked whether the predominance of CD8+ CD28? T cells in the gut may result from peripheral blood T cells preferentially migrating to the iIEL compartment and adhering to iEC. Compared with CD4 cells, adhesion of resting CD8+ T cells to iEC cell lines was significantly higher. Adhesion could be blocked with a MoAb to gp180, a molecule expressed on iEC which is known to interact with CD8/lck. No significant difference in the level of adhesion was observed between CD8+ CD28+ and CD8+ CD28? T cells. Thus CD8 cells may preferentially migrate to the iIEL compartment, but loss of CD28 expression could occur in situ after migration. Consistent with this hypothesis, the CD8+ CD28? cells became enriched after co-culturing T cells with iEC cell lines and primary iEC. Induction of the CD8+ CD28? phenotype in cord blood and adult T cells was observed in co-cultures with iEC and also with mitogens and superantigens. In the latter case, CD28 down-modulation was seen specifically in the Vβ subset targeted by the superantigen, indicating that loss of CD28 expression is a direct result of T cell receptor (TCR)-mediated stimulation. The combined results suggest that CD8+ CD28? T cells are antigen experienced T cells, and that they may have a survival advantage in the presence of gut epithelial cells in vitro. This may contribute to the predominance of CD8+ CD28? T cells in the iIEL compartment. 相似文献
99.
100.
仲跻云 《山东医大基础医学院学报》2003,17(4):234-235
目的 :探讨改良泪道探通术注入素高捷疗眼膏治疗泪道阻塞的临床效果。方法 :用 7~ 9号腰脊穿刺针针头去尖 ,磨光后制成改良空管式泪道探针。为慢性泪囊炎 98例、10 2眼探通泪道后沿空管注入素高捷疗眼膏 ,使之布满泪道内壁 ,尽快修复探通的泪道内皮 ,达到扩张疏通的目的。以同一疾病 84例、85眼为对照组 ,以 1~ 3号银质泪道扩张针扩通泪道 ,留针 15min ,隔日 1次 ,共扩张 2~ 3次 ,扩张后用 0 .2 5 %氯氟液冲洗。结果 :术后随访 3个月 ,观察组治愈率为 97.0 5 %,对照组治愈率为 9.4 1%,差异有高度显著性 (P<0 .0 1)。 结论 :用改良的泪道探针探通泪道后注入素高捷疗眼膏 ,促使泪道修复 ,是治疗泪道阻塞或狭窄的有效方法。 相似文献