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91.
1. The effects of histamine on gastric mucosal blood flow in the presence and absence of gastric acid secretion were studied in the rat. 2. Histamine, in doses greater than those required to stimulate maximal acid secretion, caused a small increase in mucosal blood flow per unit acid output. 3. When acid secretion was inhibited by methyl analogues of prostaglandin E2, histamine reduced arterial blood pressure and gave a dose dependent rise in mucosal blood flow. 4. When acid secretion was inhibited by the histamine H2-receptor antagonists, burimamide and metiamide, histamine still increased mucosal blood flow. 5. The use of H1-receptor antagonists to inhibit the histamine-induced hyperaemia was made difficult by their vasodilator actions. 6. The selective histamine H2-receptor agonist, 4-methyl histamine, had no effect on arterial blood pressure in doses which stimulated acid secretion. The increase in mucosal blood flow which accompanied the stimulation of acid secretion was inhibited by the anti-secretory prostaglandins and H2-receptor antagonists. 7. The selective histamine H1-receptor agonist, 2-pyridyl ethylamine, had no effect on acid output but increased resting mucosal blood flow. 8. These results suggest that histamine H2-receptors, primarily concerned with acid secretion, and H1-receptors concerned with vasodilatation are both present in the rat gastric mucosa. 相似文献
92.
The effect of cetylpyridinium chloride (CPC) on pathogenic fungi and Nocardia asteroides was studied. Sputa seeded with each of 11 organisms (Aspergillus flavus; Aspergillus fumigatus, Blastomyces dermatitidis, Candida albicans, Coccidioides immitis, Cryptococcus neoformans, Geotrichum candidum, Histoplasma capsulatum; Nocardia asteroides, Paracoccidioides brasiliensis, and Sporothrix schenckii) were treated with CPC and kept for 2, 5 and 9 days. The CPC reagent used (0.5% CPC and 0.5% sodium chloride) is one the Mycobacteriolgoy Branch at the Center for Disease Control added to sputa before shipping them to laboratories for recovery of mycobacteria. None of the organisms tested survived this treatment, and none was recovered on mycological or mycobacteriological media. Seeded sputa containing these organisms were also tested with a second CPC reagent (0.02% CPC and 0.5% sodium chloride) and held for 2, 5 and 9 days. A few colonies of A. flavus, A. fumigatus, and N. asteroides were recovered from these samples. Neither the morphology of the fungi nor their stainability by the fluorescent antibody method was affected by treatment with the reagent containing 0.5% CPC. However, the background material in smears from the 0.5% CPC-treated samples retained the conjugate, and this made weakly fluorescing organisms more difficult to detect. The 0.5% CPC treatment did not alter the morphology of N. asteroides or its ability to be stained with Kinyoun acid-fast stain. 相似文献
93.
After presenting the topographical and pathological basis for the habitual luxation of the shoulder joint, our experience with the Bankart-Müller operation on 38 of our own patients was described. The results are characterized as very good, particularly two years and longer after the operation. 相似文献
94.
The localization of soluble, cercarial antigen preparation (CAP) in cercariae and schistosomules of Schistosoma mansoni was performed at the light and electron microscope levels using the unlabeled antibody method. Reaction produce was observed associated with the contents of the pre- and postacetabular glands and with the filamentous coat of mature cercariae. No reaction product was observed associated with the glycoacalyx of schistosomules. However, several schistosomules did retain remnants of their filamentous coats and reaction product was observed associated with those remains. CAP components were also observed in the area surrounding the intrasporocyst cercariae. 相似文献
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JL Wright LM Lawson PD Pare BJ Wiggs S Kennedy JC Hogg 《Canadian Metallurgical Quarterly》1983,127(4):474-477
To investigate the effect of smoking status on pulmonary function and pathologic changes in the peripheral airways, we studied 97 patients who underwent thoracotomy for coin lesions. The patients were divided into 4 groups: nonsmokers (n = 9), current smokers (n = 51), and those who had ceased smoking for less than (n = 18) or more than (n = 19) 2 yr prior to surgery. We found that current smokers had evidence of air-flow obstruction with abnormal lung volumes when compared with nonsmokers. Ex-smokers had lung volumes similar to those of nonsmokers, but showed evidence of obstruction, with the FEV1/FVC between the values found for nonsmokers and current smokers. Examination of the small airways showed that the membranous bronchioles of current smokers and ex-smokers displayed only increased goblet cell metaplasia when compared with those in nonsmokers; the respiratory bronchioles of current and ex-smokers showed increases in intraluminal and airway wall inflammatory cells, wall fibrosis, and pigment deposition. We conclude that patients who currently smoke cigarettes have reduced lung function that is associated with abnormalities of airway structure. Although those who have stopped smoking have function that is closer to the nonsmoking group, there is no apparent difference in structural change between current and ex-smokers. 相似文献
100.
Twenty-one cases of mammary tuberculosis are reported and the attendant clinical and histological difficulties described. It is probable that contemporary clinicians would now make the clinical diagnosis of breast abscess or carcinoma. Furthermore, the histological features (without demonstration or culture of the organism) may be confused with those granulomatous epithelloid reactions seen in mammary duct ectasia (comedo cell mastitis, plasma cell mastitis) and in traumatic fat necrosis. 相似文献