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31.
N.J. TarantoS.P. Cajal M.C. De MarziM.M. Fernández F.M. FrankA.M. Brú M.C. MinvielleJ.A. Basualdo E.L. Malchiodi 《Transactions of the Royal Society of Tropical Medicine and Hygiene》2003,97(5):554
In a study, carried out in 2000, of the clinical and parasitological status of a Wichi Aboriginal community living in the suburbs of Tartagal, northern Salta, Argentina, 154 individuals were screened for parasitic infections. Ninety-five faecal samples were also obtained from the same population. Ninety-three percent of the subjects were positive for 1 or more of the parasites investigated by direct test and 70.5% of them had parasitic superinfection. The most frequent helminths were Strongyloides stercoralis (50.5%) and hookworm (47.4%). We found low reinfection rates and a long reinfection period after treatment and provision of safe water and sanitation. Serum reactivity of these patients was analysed by enzyme-linked immunosorbent assay and indirect immunofluorescent assay and 22.1% of them had anti-Toxocara antibodies, 16.2% were positive for a complex antigen of Leishmania braziliensis, 29.9% were positive for a complex Trypanosoma cruzi antigen, and 17.5% were positive for a specific Trypanosoma cruzi antigen, Ag1 63136/cruzipain. 相似文献
32.
F.D. CASTILLO M. J. BENSON D. L. WINGATE T. SAMARAS N. M. SPYROU 《Neurogastroenterology and motility》1994,6(1):11-19
Abstract Detection of peristalsis in the human small intestine has been limited in the past by both the available measurement techniques and the complexity of this activity. Recent developments in ambulant recording have provided a means of monitoring the occurrence of intestinal contractions at multiple sites in the small bowel, but the problem of complexity remains. Using digital data recorded from an intra-luminal strain-gauge transducer in the proximal gut, an algorithm was implemented to identify and classify contractile events within the small bowel. By modelling propagated activity the effect of varying transducer spacing and the number of transducers used was assessed. The question of variability of apparent velocity of peristaltic contractions was examined using successive cross-correlation calculations to extract underlying phase differences between samples of 512 minutes of manometric recording over 150 mm of human small bowel. The effective velocity was found to have a median value of 14 mm sec-1 and an inter quartile range of 12–18 mm see-1 ). It is proposed that, in dynamically tracking variations in phase difference between adjacent recording sites, cross-correlation techniques should be used to control the parameters used for the recognition of propagated contractile events and thereby improve the specificity of this process. 相似文献
33.
小肠粘膜下层的制备及细胞相容性的实验研究 总被引:10,自引:1,他引:9
目的了解猪小肠粘膜下层(SIS)的细胞相容性,探讨用SIS为生长载体复合骨髓基质干细胞(BMSCs)构筑组织工程骨的可能性。方法用物理和化学方法处理猪小肠粘膜下层,将兔骨髓基质干细胞与SIS进行体外复合培养,分别进行组织学、相差显微镜和扫描电镜观察。结果经物理和化学处理的SIS纯度高,孔隙多,胶原纤维未受损;BMSCs在SIS材料上生长、粘附、增殖,并能长入材料的孔隙内,分泌大量的细胞外基质成分。结论SIS的细胞相容性良好,不影响BMSCs的形态,对细胞生长和功能表达无抑制作用,可以用作骨组织工程的支架材料。 相似文献
34.
35.
肠道T细胞淋巴瘤临床分析 总被引:1,自引:0,他引:1
本文总结报告了3例肠道T细胞淋巴瘤(intestinal T-cell lymphoma,ITCL)的诊治资料,并结合文献复习,发现IT—CL多见于中年男性,以腹痛、血便、发热、体质量下降为主要症状,治疗效果差,预后不良。病理改变以肠道溃疡形成为特点,溃疡形态呈多形性、多灶性、不规则,镜下瘤细胞明显异型、弥漫性浸润,中至大细胞多见。肿瘤细胞呈T细胞表型。ITCL临床少见,缺乏特异性临床表现,极易误诊。故临床医师应重视对ITCL临床病理特征、免疫表型和基因型的研究,注意识别,促其早期诊治。 相似文献
36.
Jun-ichi Shikata MD Kazuhiko Ohtaki Kenjiro Amino Yoshitsugu Takeda 《Surgery today》1990,20(6):660-664
Two nationwide questionnaire surveys of intestinal obstruction in Japan were undertaken, covering two two-year periods, from
January, 1975 to December, 1976 and from January, 1985 to December, 1986, respectively. The findings of a comparative review
of these two surveys indicated that although the overall mortality of intestinal obstruction had not changed between 1975/76
and 1985/86, being 6.8 per cent and 6.5 per cent, respectively, simple adhesive obstruction had decreased from 3.2 per cent
in 1975/76 to 2.0 per cent in 1985/86. The main cause of adhesion was laparotomy and in cases of both simple adhesive obstruction
and strangulated adhesive obstruction, the rate of adhesion secondary to laparotomy of the upper gastrointestinal tract and
colon and rectum had increased between 1975/76 and 1985/86. Obstructions caused by neoplasms had increased from 8.2 per cent
in 1975/76 to 10.0 per cent in 1985/86, while those caused by adhesions had incresed further still, from 42.5 per cent in
1975/76 to 60.8 per cent in 1985/86. Among the latter group, nonoperatively treated cases had increased, which may be accounted
for by the fact that facilities which adopt non-operative treatment using intestinal decompression as the first choice for
simple adhesive obstruction cases have increased. In both surveys, the mortality of cases receiving nonoperative treatment
was lower than that of operative cases. 相似文献
37.
G. Bogeski N. P. Lean P. D. Kitchener A. Timar-Peregrin G. J. Sanger† A. D. Shafton & J. B. Furness 《Neurogastroenterology and motility》2003,15(4):417-425
Distension of the intestine is commonly used to elicit reflex responses at other sites in the gastrointestinal tract, and also to evaluate pain of intestinal origin. The sensory neurones, that initiate the reflexes or pain responses, react to the forces generated in the wall of the intestine. Thus, the responses of the intestine at the site of distension, particularly changes in contractile activity, influence the signals from the gut. In the present work we have analysed the relationship between distension and pressure changes in the jejunum of the rat, in vivo. Isovolumic distension for 5 min caused an initial pressure increase which declined quickly in the first 30 s, and then declined more slowly. Phasic pressure increases were superimposed on the baseline pressure change. Hexamethonium blocked the phasic pressure increases, whereas the initial rapid and subsequent slower pressure decline during distension persisted. Inhibition of nitric oxide synthase (NOS) increased intraluminal pressure and caused increased frequency and irregularity of phasic pressure increases. However, the decline in jejunal pressure during distension was not changed by inhibition of NOS. The pressure decline during isovolumic distension was similar whether saline or paraffin oil were used to distend the intestine, indicating that the decline was not due to increased hydrostatic pressure causing water and electrolyte to cross the mucosal epithelium from the lumen to the intestinal interstitium. Hyoscine had no significant effect on the pressure profile when the intestine was distended. However, when the systemic or the local circulation of the jejunum was infused with nicardipine, the pressure that was achieved during isovolumic distension was less, although the rate of change in pressure during the slow decline was similar. It is concluded that distension evokes phasic pressure increases in the jejunum, that are nerve-mediated, and increases the tension in the wall through a stretch-activated increase in contractile force generated by the circular muscle. The decline in pressure during maintained distension is primarily a consequence of visco-elastic properties of the wall of the intestine. 相似文献
38.
Chronic ischemia produces corresponding tissue hypoplasia. However, here we report a distinctive hypertrophy of the intestine due to chronic mesenteric insufficiency, which was confirmed by angiography in two patients with opposite characteristic pathologic presentation of intestine. During surgery of the first patient, an approximately 60cm long ileum with sausage consistency and cyanosis color was identified proximal to the caecum; wall-attached thromboembolism material and the hypertrophied segment of ileum were removed. In the other patient, the intestine wall was paper thin; after aorto-mesenteric bypass the intestine wall grew thicker. Post operative recovery of both patients was uneventful. The commonly observed situation after a long-standing hypoxic insult in a setting of chronic mesenteric ischemia is that the target tissue will at least develop a slight hypoplasia. However, the cases we present here had either pronounced hyperplasia or severe hypoplasia. We thus report it, expecting to identify a special mechanism to explain this paradox. 相似文献
39.
40.
The suprachiasmatic nucleus (SCN) of rat and hamster have been studied extensively and shown to play critical roles in circadian rhythmicity. [125I]Vasoactive intestinal peptide (VIP) binding levels are high in the rat SCN, suggesting that VIP receptors may be an important component of SCN function. In contrast to previously demonstrated diurnal variations in VIP immunoreactivity and VIP mRNA, the present study found [125I]VIP binding to be stable across the light-dark cycle in both rat and hamster SCN. High [125I]VIP labeling appeared to be coextensive with the rat SCN but extended somewhat beyond the cytoarchitectonic boundaries of the hamster SCN. Binding density in hamster SCN was slightly higher than in rat. In the developing rat SCN, [125I]VIP binding levels distinguished the SCN on embryonic day 18, and appeared to increase to postnatal day 10 before declining to adult levels. The early presence of [125I]VIP binding suggests possible involvement of VIP receptors in fetal entrainment of circadian rhythms. 相似文献