EGF加强大鼠胃壁细胞的泌酸活动

以氨基比林聚集为间接的泌酸指标，本实验观察了急性分离的大鼠胃粘膜壁细胞对ＥＧＦ的反应。结果表明：１．急性分离后３０分钟左右，壁细胞对较大剂量的ＥＧＦ（１００ｎＭ）的反应为胃酸分泌的减少；２．急性分离后６０分钟左右，壁细胞对ＥＧＦ（０．１－１００ｎＭ）的反应为泌酸活动的加强。结果提示壁细胞被分离后经历一功能恢复的过程，ＥＧＦ对壁细胞的生理作用可能是加强其泌酸活动。     

复方金银花擦剂中没食子酸的含量测定

目的：建立测定复方金银花擦剂中没食子酸的含量测定方法。方法：Novapak C18色谱柱，流动相甲醇冰醋酸-二甲基酰胺-水（2：0．5：20：90），检测波长275nm。结果：该法线性关系良好，相关系数r=0．9996，加样回收率为99．02％，RSD=1．94％。结论：该方法操作简单，分离效果好，可用于复方金银花擦剂的质量控制。     

Urinary 5-Hydroxytryptophol: A Possible Marker of Recent Alcohol Consumption

Urinary 5-hydroxytryptophol (5-HTOL) is currently being evaluated as a marker of recent alcohol consumption. To compensate for urinary dilution, the molar ratio between 5-HTOL and 5-hydroxyindole-3-acetic acid (5-HIAA) is used. The 5-HTOL/5-HIAA ratio showed a satisfactory degree of individual stability when it was followed in a group of teetotallers for 1 month. The mean value of 5-HTOL/5-HIAA in a group of 69 persons abstaining from alcohol was 7.6 (pmoles 5-HTOL/nmoles 5-HIAA). Ninety-seven percent had values ranging from 4 to 17, with no value exceeding 20. A group of healthy volunteers were tested 12 hr after alcohol consumption and showed a dose-dependent and statistically significant elevation in the 5-HTOL/5-HIAA ratio. Four regular alcohol consumers who were followed during a period of 3 months of drinking had elevated values of the 5-HTOL/5-HIAA ratio in 60% of their urine samples. The present study indicates that urinary 5-HTOL/5-HIAA is a sensitive and reliable marker of recent alcohol consumption. We propose that a 5-HTOL/5-HIAA ratio greater than 20 (pmoles/nmoles) can be used to indicate recent alcohol consumption. This limit gives a low frequency of false positives; the statistical probability of having a value greater than 20 during abstinence from alcohol was calculated to be less than 0.001.     

Surface coat of sheep pulmonary intravascular macrophages: Reconstitution,and implication of a glycosyl-phosphatidylinositol anchor

Background: Pulmonary intravascular macrophages (PIMs) of sheep have a globular surface coat that facilitates endocytosis of tracer particles and Escherichia coli lipopolysaccharide, and is disrupted by the heparin and Brefeldin A treatments. The present study investigated the in vivo dynamics of the coat globules following heparin-mediated removal, and the mechanism of globule organization on the plasma membrane of PIMs in vitro. Methods: Sheep were administered heparin at a dose of 50 IU/kg body weight IV, and euthanised at 30 min, 3, 6, 12, 48, and 120 hr (n = 2 for each treatment) after the treatment. Control sheep (n = 2) were injected with normal saline solution. The tissues were processed for an ultrastructural examination and acid phosphatase (ACPase) cytochemistry. Heparintreated lungs were subjected to morphometric analysis of the coat globules. Lung tissues from normal sheep (n = 2) were incubated with phosphatidylinositol-specific-phospholipase C (PIPLC; 2 IU/ml PBS) in vitro for 30 and 75 min. Results: Heparin study: The ultrastructural and morphometric data showed that the coat globules were removed at 30 min and reconstituted within 48 hr of the treatment. The PIMs showed priminent Golgi complexes associated with secretory vesicles, microtubules, and centriole between 3–12 hr of heparin treatment. Acid phosphatase cytochemistry also demonstrated secretory activity in the Golgi complexes of PIMs during the coat reconstitution. PIPLC study: The coat globules of PIMs were removed in a time-dependent mode by the PIPLC treatment without damage to other cell organelles. Conclusions: This study demonstrates a time-dependent reconstitution of the coat of PIMs in conjunction with secretory activity following heparinmediated removal, probably through sequenstration of the globules from blood. This ability is of functional significance as the coat mediates particle endocytosis by the PIMs. The results also suggest the presence of a glycosyl-phosphatidylinositol (GPI) anchor in tethering of globules on the plasma membrane of PIMs to offer a structural basis for their integrity in pulmonary vascular flow. © 1995 Wiley-Liss, Inc.     

Renal acid excretion in early infancy

In early infancy, complex disorders of acid base metabolism are more frequent than in any other age group, with a predisposition to metabolic acidosis due to an age-related low renal capacity for acid excretion and an unphysiologically high actual renal acid load in nutrition with common formulas. Recently in preterm and small-for-gestational-age infants, persistent maximum renal net acid excretion (NAE) with subnormal or normal blood acid base status, impaired weight gain, and adaptive hormonal reactions have been observed. Incipient late metabolic acidosis is one example of a mixed disorder of acid base metabolism with maximum renal NAE in early infancy. Alkali therapy is highly effective and can be realized both on an individual basis, using urine pH screening as a diagnostic criterium for maximum renal acid stimulation, or on a general preventive level using modified standard formula with a reduced actual renal NAE similar to that seen on alimentation with human milk. From an integrated point of view, the low glomerular filtration rate and renal capacity for acid excretion beyond the developmental age of more than 44 weeks, may well be interpreted as the result of a specific adaptation to breast feeding sparing energy, and thus an evolutionary advantage for the survival of mother and child. Received July 10, 1996; received in revised form and accepted October 7, 1996     

A follow-up study of respiratory function in workers exposed to acid aerosols in a food-processing industry

A follow-up investigation was performed on 49 female workers studied 2 years earlier in a vegetable-pickling plant. Acute and chronic respiratory symptoms and ventilatory capacity measurements were recorded during the original and the follow-up studies. Maximal expiratory flow-volume (MEFV) curves were recorded during the Monday morning work shift. The forced vital capacity (FVC), 1-s forced expiratory volume (FEV1), and flow rates at 50% and the last 25% of the FVC (FEF50, FEF25) were measured. There were small increases in the prevalence of chronic symptoms between the two studies for both smokers and nonsmokers, but these did not reach statistical significance. Five workers at the time of the initial study had a diagnosis of occupational asthma; only one of these was still working at the time of follow-up. Workers lost to the follow-up had lower lung function than those seen at follow-up. In workers who were followed, larger than expected mean annual declines were noted for all ventilatory capacity parameters in both smokers (FVC 0.070 l, FEV1 0.070 l; FEF50 0.355 l/s, FEF25 0.270 l/s) and nonsmokers (FVC 0.045 l, FEV1 0.045 l, FEF50 0.285 l/s; FEF25 0.130 l/s). The decrease was particularly pronounced for FEF50 and FEF25. The accelerated decline in ventilatory capacity tests noted in the female nonsmokers suggests an independent effect on lung function of work exposure in this environment. Our data confirm that work in the pickling industry, particularly in small, poorly regulated plants, has deleterious effects on respiratory function. Received: 24 September 1996 / Accepted: 19 June 1997     

Comparison of acid reduction in antiulcer operations

Background: Three acid-reducing operations have recently been described for the laparoscopic treatment of peptic ulcer disease. These consist of a posterior truncal vagotomy combined with either (1) an anterior seromyotomy (SERO), (2) an anterior highly selective vagotomy (AHSV), or (3) a linear stapled lesser curvature excision (STAP). The purpose of this study was to investigate the physiologic effects of these procedures in terms of basal and maximal acid outputs. Methods: Fifty New Zealand rabbits were prospectively randomized into five open laparotomy groups (n= 10): a control group without vagal manipulation (CON), a bilateral truncal vagotomy with pyloromyotomy group (VP), a SERO group, an AHSV group, and a STAP group. All animals underwent placement of a gastrostomy tube for subsequent gastric secretory analysis. On postoperative day 6, basal acid outputs (BAO) and maximal acid outputs (MAO) following IV pentagastrin stimulation (30 μg/kg/h) were measured. Results were compared statistically using the ANOVA method. Results: Pentagastrin stimulation was associated with a significant increase in MAO in the CON group (p < 0.05 vs BAO); however, this response was effectively blunted in all the experimental groups. There were no differences in BAO or MAO between any of the vagotomized groups (SERO, HSV, STAP, VP). Conclusions: We conclude that the three acid-reducing procedures modified for laparoscopy are equally efficacious in reducing gastric acid secretion and that they compare favorably with VP. To our knowledge, this is the first report comparing basal and stimulated gastric acid secretion between these new acid-reducing techniques. Received: 27 March 1996/Accepted: 17 July 1996     

An Electron Microscopic Study on the Process of Acid Demineralization of Cortical Bone

Demineralization has been shown to foster osteoinductive properties of cortical bone grafts, yet little is known about the process of demineralization and how to control it. The purpose of this study was to investigate the process of cortical bone demineralization by using scanning electron microscopy to evaluate how hydrochloric acid demineralizes cortical bone. Results showed that in the demineralization of diaphyseal cortical bone specimens using hydrochloric acid, a uniformly thick circumferential band of demineralized bone matrix surrounds an inner undecalcified bone core as the process of demineralization occurs. The interface between the demineralized and mineralized section of the bone specimens was extremely sharp. This interface between demineralized and undemineralized bone was noted to advance as a reaction front with increasing demineralization which resulted in continuous shrinkage of the inner cortical bone core. This study suggests that cortical bone demineralization can be best described using an advancing reaction front theory, and this explanation can be used for implementation of the concept of controlled demineralization. Received: 19 December 1996 / Accepted: 25 April 1997     

酸性环境介导皮质神经元损伤及阻断酸敏感离子通道1α的神经保护作用

目的 探讨脑梗死模型中酸性环境能否介导皮质神经元损伤及阻断酸敏感离子通道1α（acidsensing ion channels1α，ASIC1α）的神经保护作用。方法 制作缺氧细胞模型、脑梗死动物模型，检测ASIC1α阻断剂对乳酸脱氢酸（lactate dehydrogenase，LDH）释放率、大鼠行为学、脑梗死体积以及ASIC1蛋白表达的影响。结果 酸性环境可以损伤皮质神经元，加重缺氧对细胞的毒性作用，经侧脑室注射ASIC1α阻断剂可以改善脑梗死大鼠的行为学改变，梗死体积明显减小（P〈0.05）；随梗死时间延长，缺血半暗带ASIC1表达增加，在缺血后24h表达量较明显。结论 酸性环境导致皮质神经元损伤，其损伤机制与缺血后神经元ASIC1α开放以及表达增加有关；阻断ASIC1α具有神经保护作用。     

高效液相法测定金樱子中三萜酸类成分的含量

定量测定不同产地金樱子中2α,3α,19α,23-四羟基乌苏-12-烯-28-羧酸的含量.采用高效液相法,色谱柱:Kromasil-C18(4.6 mm×250 mm,5 μm)柱,大连依利特公司;检测波长203 nm,柱温:35 ℃;流动相:乙腈-水(35:65),流速1 mL/min.结果表示所测成分与其他组分具有良好的分离度,线性范围为0.4～10 μg, 加样回收率为102.5%,RSD=2.66%.说明不同产地的三萜类有机酸的含量差别很大.本方法操作简单,结果准确,可用于含2α,3α,19α,23-四羟基乌苏-12-烯-28-羧酸的药物的含量测定.