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61.
62.
An essential role for an intact vagal nerve has been proven in the development of gastric mucosal cyto- and general protection. On the other hand, chemically-induced (ethanol, HCl, indomethacin) gastric mucosal damage is enhanced after acute surgical vagotomy. The aims of this paper were to study the possible mechanisms of the vagal nerve in the development of gastric mucosal defense. The following questions were addressed: 1) effect of surgical vagotomy on the development of ethanol- (ETOH), HCl-, and indomethacin (IND)-induced gastric mucosal damage; 2) changes in the gastric mucosal defense by scavengers, prostacyclin and other compounds (small doses of atropine and cimetidine: 3) changes in the gastric mucosal vascular permeability due to chemicals; 4) effect of indomethacin in the ETOH and HCl models with and without surgical vagotomy; 5) changes in the gastric mucosal content of prostacyclin and PGE2 in the ETOH and HCl models after surgical vagotomy; and 6) changes in the role of SH-groups in gastric mucosal defense after surgical vagotomy. It was found that: 1) the gastric mucosal damage produced by chemicals (ETOH, HCl, and indomethacin) was enhanced after surgical vagotomy; 2) the cyto- and general gastric protective effects of β-carotene, prostacyclin, and small doses of atropine and cimetidine disappeared after surgical vagotomy; 3) the vascular permeability due to chemicals (ETOH, HCl, indomethacin) significantly increased after surgical vagotomy in association with an increase in both number and severity of gastric mucosal lesions; 4) IND alone (in animals with an intact vagus) did not produce gastric mucosal lesions (in 1-h experiments), but it aggravated ETOH-induced gastric mucosal damage (both its number and severity); 5) the gastric mucosal levels of prostacyclin and PGE2 decreased after surgical vagotomy; 6) IND application (after surgical vagotomy) decreased further the tissue levels of prostacyclin and PGE2 in association with an increase of gastric mucosal damage; and 7) the gastric mucosal protective effects of SH-groups were abolished by surgical vagotomy. 相似文献
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Sa´nchez A. Rami´rez M.E. Torres L.G. Galindo E. 《World journal of microbiology & biotechnology》1997,13(4):443-451
Seventeen wild-type Xanthomonas isolates were screened in terms of broth viscosity in shake-flasks. As culture conditions affect polymer characteristics, a fair comparison among isolates required their cultivation in a fermenter under controlled dissolved oxygen tension. Three isolates and a reference strain were studied. The mean molecular weights and molecular weight distributions of their xanthans were determined. Products showed different pyruvate (0.2–7%), acetate (5–10%) and proteinaceous nitrogen (1–3%) contents. The selected isolates exhibit properties which could improve xanthan gum production and some could be used to produce polymers with specific characteristics. 相似文献
65.
Exemestane experience in breast cancer treatment 总被引:2,自引:0,他引:2
P. E. Lnning R. Paridaens B. Thürlimann G. Piscitelli E. di Salle 《The Journal of steroid biochemistry and molecular biology》1997,61(3-6):151-155
Exemestane is a very potent, orally active, selective and long-lasting steroidal irreversible inhibitor of aromatase. It is 150 times more potent than aminoglutethimide (AG) in inhibiting human placental aromatase (Ki of 4.3 and 671 nM, respectively). The compound is presently under phase III evaluation in Europe and the U.S.A. for the treatment of postmenopausal advanced breast cancer (ABC). Clinical pharmacology studies have been carried out with single doses ranging from 0.5 to 800 mg and repeated doses of up to 600 mg a day, in 132 postmenopausal healthy volunteers and in 185 post-menopausal women with ABC. Results obtained using a very specific and sensitive analytical method (high performance liquid chromatography—radioimmunoassay; HPLC—RIA) indicated that exemestane is extremely effective in inhibiting plasma estrogens levels. Estrogen inhibition is clearly evident at 5 mg a day and maximal suppression for E2, E1 and E1S (>85%, >90% and>90%, respectively) is obtained at 10–25 mg a day. Data from non-controlled phase II studies involving more than 400 patients indicated a clear anti-tumour activity in postmenopausal ABC patients failing multiple hormonal treatments. In 62 patients progressing on AG (≥500 mg a day) exemestane treatment resulted in an objective response rate of approximately 24%; disease stabilization ≥24 weeks was observed in an additional 24% of cases. With regard to safety, although daily doses up to 600 mg were administered, the maximal tolerated dose was not achieved; reported symptoms were mainly related to the pharmacological action of the compound and were usually mild to moderate in severity, resulting in the discontinuation of therapy in less than 3% of cases. In conclusion, the available results suggest that exemestane treatment is associated with minimal toxicity, and may be of significant benefit for ABC women who have exhausted conventional therapy. 相似文献
66.
Inhibition enzyme-linked immunosorbent assay for detection of Pseudomonas fluorescens on meat surfaces.
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An inhibition enzyme-linked immunosorbent assay was developed for Pseudomonas fluorescens enumeration of meat surfaces. The assay detected contamination levels as low as 3 x 10(5) bacteria per ml and could be completed within 4 h. It could be used as a framework for a test system for quantifying P. fluorescens spoilage in meat products. 相似文献
67.
M. P. Francescato T. Talon P. E. di Prampero 《European journal of applied physiology and occupational physiology》1995,71(4):355-361
Energy costs and energy sources in karate (wado style) were studied in eight male practitioners (age 23.8 years, mass. 72.3 kg, maximal oxygen consumption (VO2max) 36.8 ml · min–1 · kg–1) performing six katas (formal, organized movement sequences) of increasing duration (from approximately. 10 s to approximately 80 s). Oxygen consumption (VO2) was determined during pre-exercise rest, the exercise period and the first 270 s of recovery in five consecutive expired gas collections. A blood sample for lactate (la–) analysis was taken 5 min after the end of exercise. The overall amount of O2 consumed during the exercise and in the following recovery increased linearly with the duration of exercise (t) from approximately 1.51 (for t equal to 10.5 s (SD 1.6)) to approximately 5.81, for t equal to 81.5 s (SD 1.0). The energy release from la– production (VO21a
–) calculated assuming that an increase of 1 mmol · l–1 la– corresponded to a VO2 of 3 mlO2 · kg–1 was negligible for t equal to or less than 20 s and increased to 17.3 ml · kg–1 (la– = 5.8 mmol · l–1 above resting values) for t equal approximately to 80 s. The overall energy requirement (VO2eq) as given by the sum of VO2 and VO2la
– was described by VO2eq = 0.87 + 0.071 · t (n = 64; r
2 = 0.91), where VO2eq is in litres and t in seconds. This equation shows that the metabolic power (VO2eq · t
–1) for this karate style is very high: from approximately 9.51 · min–1 for t equal to 10 s to approximately 4.91 · min–1 for t equal to 80 s, i.e. from 3.5 to 1.8 times the subjects' VO2max. The fraction of VO2eq derived from the amount of O2 consumed during the exercise increased from 11% for t equal to 10 s to 41 % for t equal to 80 s whereas VO21a
– was negligible far t equal to or less than 20 s and increased to 13 % o for t equal to 80 s. The remaining fraction (from 90% for t equal to 10 s to 46% for t equal to 80 s), corresponding to the amount of O2 consumed in the recovery after exercise, is derived from anaerobic alactic sources, i.e. from net splitting of high energy phosphates during the exercise. 相似文献
68.
69.
Résumé Une candidose intestinale associée à une tumeur épithéliale, à métaplasie glandulaire, à pouvoir invasif marqué, provoquant une gêne du transit, a été découverte chez un Babouin de Guinée,Papio papio (Desm.) de la collection du Parc zoologique de Paris. A cette occasion nous avons rapporté les résultats concernant deux autres affections du tube digestid de nos Babouins captifs.
Report of a case of candidiasis of the digestive tract associated to an obstructive epithelial tumor, with great invasive ability, in a captive Baboon,Papio papio (Desm.). Included is a discussion of the incidence of some intestinal disturbances involving candidiasis of subhuman Primates.相似文献
70.
A total of 51 restriction sites were recognized within the BK virus genome by the combination of 10 different restriction endonucleases. These sites were mapped and oriented relative to one another as well as to the five fragments generated by the digestion of BK virus DNA with HindIII and EcoRI. The result was a comprehensive physical map suitable for in-depth characterization of the functions of BK virus at the molecular level. 相似文献