HYDROGEN AND METHANE PRODUCTION IN MAN
HYDROGEN AND METHANE PRODUCTION IN MAN
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DOI：
10.1111/j.1749-6632.1968.tb19033.x
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发表时间：
1968-01-01
影响因子：
5.2
通讯作者：
INGELFINGER, FJ
中科院分区：
文献类型：
--
作者：
LEVITT, MD;INGELFINGER, FJ
方法用三腔聚乙烯管对 9 名年轻对照受试者进行插管，该管的三个孔口间隔 60 厘米。通过透视确定远端孔口位于回肠末端。因此，中间开口位于近端回肠上游 60 cm 处，近端开口位于空肠中上游 60 cm 处（图 1）。将含有 0.5% 六氟化硫 (SFla) 的空气或氮气作为标记气体，通过近端开口以 30 cc/min 的速率持续注入。经过一小时的“冲洗”期并建立约等于输注速率的直肠气体流出后，通过肠管从近端回肠和回肠末端以及通过直肠管从直肠采集气体样品。六氟化硫被用作标记气体，因为之前的研究表明它极难溶于水，并且从体腔中吸收非常缓慢。在我们的研究条件下，注入的六氟化硫中只有约 1% 被吸收，并出现在呼出的空气中。由于 SFls 不是在胃肠道 (GI) 中产生，并且仅被最低限度地吸收，因此 SFls 浓度的变化表明已向输注液中添加或减去了净气体体积。因此，SFls 用于校正稀释变化，类似于肠道吸收研究中使用聚乙二醇。通过气相色谱分析收集的样品，并通过标准恒定输注方程计算 H2 或 CH 通过每个采样点的速率 (cclmin)。 4
MethodNine young control subjects were intubated with a triple-lumen polyvinyl tube constructed so that the three orifices of the tube were separated by intervals of 60 cm.The tube was passed until the distal orifice was located in the terminal ileum, as determined by fluoroscopy. The middle opening was therefore 60 cm upstream in the proximal ileum, and the proximal opening was another 60 cm upstream in the midjejunum (FIGURE 1). Air or nitrogen containing 0.5% sulfur hexafluoride (SFla) as a marker gas was constantly infused at a rate of 30 cc/min through the proximal opening. Following a one-hour “washout” period and the establishment of an outflow of gas from the rectum approximately equaling the infusion rate, gas samples were collected anaerobically from the proximal ileum and terminal ileum via the intestinal tube and from the rectum via a rectal tube. Sulfur hexaflouride was used as a marker gas because previous studies had shown it to be extremely insoluble in water and very slowly absorbed from body cavitiess Under the conditions of our studies, only about 1% of the infused SFls was absorbed, and appeared in expired air. Since SFls is not produced in the gastrointestinal (GI) tract, and is only minimally absorbed, changes in SFls concentration indicate that a net volume of gas has been added to, or subtracted from, the infusate. Thus, SFls was used to correct for dilution changes similar to the use of polyethylene glycol in intestinal absorption studies. The collected samples were analyzed by gas chromatography, and the rate (cclmin) at which H2 or CH, passed each sampling site was calculated by means of standard constant infusion equations. 4