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41.
Inhibitory activity of enterotoxin from Escherichia coli and Vibrio cholerae was associated with the ganglioside fraction of human milk. Both the milk fat and skim milk contained gangliosides that inhibited the toxins. The most purified milk fraction contained three glycolipid components, of which two migrated close to ganglioside GM1 on thin-layer chromatography plates. A component with a slightly different mobility from GM1 appeared to be associated with the inhibitory activity. Milk ganglioside fraction, derived from 2 ml of human milk, contained 1 to 4 micrograms of lipid-bound sialic acid and completely inhibited 0.1 micrograms of cholera toxin in rabbit intestinal loop experiments. It is suggested that human milk gangliosides, although present only in trace amounts, may be important in protecting infants against enterotoxin-induced diarrhea.  相似文献   
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荧光分光光度法测定姜黄制剂中的姜黄素   总被引:11,自引:0,他引:11  
用荧光分光光度法测定姜黄胶囊制剂中的姜黄素。以四氢呋喃为溶剂,姜黄素的激发波长和发射波长分别为Ex=442nm,Em=475nm。姜黄素标准曲线的线性范围为0.010~0.40fg/ml。最低检测浓度5ng/ml;回收率100.00%±0.28%;RSD<1%。本法操作简便、快速、灵敏,适用于姜黄制剂中姜黄素的含量。  相似文献   
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Alveolar macrophages (AMs) are capable of producing a variety of inflammatory mediators including those derived from arachidonic acid, the prostaglandins (PGs), leukotrienes (LTs) and hydroxyeicosatetraenoic acids (HETEs). Inflammation associated with release of arachidonate-derived mediators is a result of the combined actions of all of these mediators. Thus, it is critical to determine the entire spectrum of arachidonate-derived metabolites that AMs are capable of producing. In this study bovine AMs were prelabeled with [3H]arachidonic acid prior to stimulation with serum-treated zymosan, phorbol myristate acetate (PMA), or the calcium ionophore A23187. The total release of arachidonate metabolites into the culture media was measured by reverse-phase HPLC with on-line radiometric detection. All stimuli used induced production of metabolites of the cyclooxygenase pathway with thromboxane B2 and HHT being the major metabolites. Lesser amounts of PGF2, PGE2, and PGD2 were produced. Only stimulation with A23187 resulted in production of LTB4 and 5-HETE, products of the 5-lipoxygenase pathway. This latter result indicates that the two major pathways of arachidonate metabolism in AMs may be selectively stimulated. Such an effect could have important consequences in the development of pulmonary inflammation. Furthermore, the spectrum of arachidonic acid metabolites produced by bovine AMs closely resembles that of human AMs, in contrast to rodent AMs.  相似文献   
46.
We have defined the metabolites of arachidonic acid (AA) secreted by alveolar macrophages (AMs) of bighorn sheep and domestic sheep in response to three agents: calcium ionophore A23187, phorbol myristate acetate (PMA), and opsonized zymosan. Cells were labeled with [3H]AA prior to stimulation and 11 tritiated metabolites, including prostaglandins (PGs), thromboxanes (TXs), leukotrienes (LTs), and hydroxyeicosatetraenoic acids (HETEs), were detected and quantitated by high-performance liquid chromotography and radiometry. Zymosan stimulation resulted in the release of significantly elevated quantities (P<0.05), of LTB4, [5(S), 12(R)-dihydroxy-6,14-cis-8,10-trans-eicosatetraenoic acid], 5-HETE, [5(S)-hydroxyeicosatetraenoic acid], and the nonenzymatic isomers of LTB4, [LTB I, 5(S),12(R)-6-trans-LTB4] and LTB II, [5(S), 12(S)-6-trans-LTB4], from domestic sheep AM when compared to bighorn sheep AM. Phorbol myristate acetate (PMA) stimulation released significantly elevated quantities (P<0.04), of TXB2, (thromboxane B2), HHT, [12(S)-12-hydroxy-5,8,10-heptadecaenoic acid], LTB I, LTB II, and 15-HETE, [15(S)-hydroxyeicosatetraenoic acid] from domestic sheep AMs when compared to bighorn sheep AMs. However, after A23187 challenge, only 15-HETE was significantly elevated (P<0.04) in domestic sheep AMs when compared to bighorn sheep AMs. These clear differences in AA metabolism of AMs obtained from bighorn and domestic sheep in response to three different agonists suggest not only different control mechanisms for lung metabolism of AA in the two species, but also suggest that differences in the metabolites released may lead to quite different regulation of lung defense mechanisms in the two sheep spicies.  相似文献   
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AIMS: To obtain the recorded prevalence of foetal alcohol syndrome (FAS) and foetal alcohol spectrum disorders (FASD) in Norway, and evaluate the effect of a general information program to increase the recognition of FAS/FASD for health care and social workers. METHODS: A questionnaire regarding prevalence of FAS/FASD was sent to all Norwegian paediatric and child psychiatry departments. In the region Hordaland county, an information program was carried out to educate health-care and social workers on symptoms and signs of FAS/FASD, and referral was encouraged for suspected cases. Referred children received a neuropaediatric evaluation, and the effect of the information program on recorded FAS/FASD was recorded. RESULTS: Based on the national survey, a prevalence of 0.3 per 1000 was calculated. After the information program, the estimated prevalence in Hordaland County increased to 1.5 per 1000. In 5 years, 25 children were diagnosed with FAS and 22 with FASD. One-third of all children were mentally retarded. Microcephaly and neuroimpairments were more common among FAS children. Almost all children met the criteria of ADHD. CONCLUSION: The rate of FAS/FASD may be greatly underestimated because of lack of knowledge. An information program aimed at health-care and social workers is effective.  相似文献   
49.
This study assessed potential teratogenic properties of benzodiazepine (BZD) intake during early pregnancy. Four neonatal diagnoses of congenital malformations (embryopathy and fetopathy, unspecified; unspecified congenital malformations of the nervous system; cleft palate and cleft lip; congenital malformations of the urinary tract) were selected. The authors' previous clinical experience had shown these diagnoses to be characteristic of infants born to mothers with excessive intake of BZD in early pregnancy. The selected diagnoses were present in 25 of 10,646 liveborn infants (2.3 per 1000) delivered by mothers living in the city of Gothenburg in 1985 and 1986. In 18 of these cases, it was possible to analyse maternal plasma, and eight samples (44 per cent) were found to be BZD-positive. Of 60 controls, two maternal blood samples (3 per cent) were positive for BZD. The difference is highly significant and suggests an association between these congenital malformations and BZD consumed during early gestation.  相似文献   
50.
On rare occasions, excessive lipase production by functioning pancreatic acinar cell carcinoma results in subcutaneous and intraosseous fat necrosis. A patient with subcutaneous nodules and osteolytic lesions from metastatic fat necrosis associated with this malignancy is reported. Prompt recognition of the syndrome led to complete resection of the otherwise asymptomatic neoplasm of the exocrine pancreas.  相似文献   
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