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A case of gasless laparoscopic esophagogastric myotomy for achalasia is presented. The technical aspects of the technique as well as the benefits of this approach are reviewed. 相似文献
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Release of cholecystokinin from rat cerebral cortex in vivo: role of GABA and glutamate receptor systems 总被引:1,自引:0,他引:1
Using cortical cups in chloralose-urethanized rats, the in vivo release of cholecystokinin-like immunoreactivity (CCK-LI) from cerebral cortex was examined. Resting levels of cholecystokinin-like immunoreactivity ranged from 20 to 30 pg/20 min sample. The addition of potassium (40 mM) in excess, resulted in a highly significant elevation in the levels of CCK-LI in the cortical superfusate. Deletion of calcium and the substitution of cobalt (10 mM), resulted in a significant reduction in both resting release and the release otherwise evoked by the addition of potassium. Focal electrical stimulation of the cortex (20 Hz), resulted in a significant (1.9 +/- 0.2-fold, n = 8) increase in the levels of CCK-LI. The addition of glutamate (10(-6)-10(-4) M) of kainic acid (10(-8)-10(-6) M), also resulted in significant elevations in the levels of CCK-LI. The co-administration of a putative glutamate receptor antagonist, kynurenic acid (10(-4) M) resulted in a significant reduction in the levels of release otherwise evoked by the addition of glutamate, but not by electrical stimulation. The addition of GABA (10(-5)-10(-3) M) resulted in a dose-dependent decrease in the resting release of CCK-LI, and the release evoked by glutamate. Picrotoxin (10(-6)-10(-4) M), resulted in a highly significant increase in the levels of CCK-LI in the cortical effluent. These results are consistent with a tonic GABAergic inhibition of CCK-releasing neurons. The treatment of the animal with diazepam (30 mg/kg, i.p.) also resulted in a significant reduction in resting release and the release otherwise evoked by focal cortical stimulation. 相似文献
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The relationship between the immunoglobulin kappa light chain allotypes and autoantibodies was studied in a series of seven human monoclonal kappa-bearing IgM antibodies with Rheumatoid Factor (RF) activity, two IgM anti-low density lipoprotein (LDL) antibodies, and one IgM anti-intermediate filament (IF) antibody. Residues at amino acid positions 153 and 191 related to the Km allotypes in human kappa chains were determined by an HPLC tryptic fingerprint and corroborated by amino acid sequence analysis. All the autoantibodies shared similar variable regions derived from the V kappa IIIb gene(s). The seven RF and the anti-IF were associated with the Km(3) constant region allotype whereas the two anti-LDL were associated with the Km(1,2) allotype. Thus, monoclonal autoantibodies showed the same Km allotypic distribution as the normal population. However, although the number of samples is small, it seems likely that a preferential association may exist between particular V kappa genes and Km alleles in the generation of autoantibodies with different specificities. 相似文献
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Atrial natriuretic peptide (ANP) is a hormone release into the circulation by atrial cardiocytes (Gutkowska et al. 1984). Extracellular fluid volume expansion acts as a powerful stimulus for ANP secretion and results in the augmentation of its plasma concentration (Lang et al. 1985). Patients with active acromegaly demonstrate the increased extracellular fluid volume (Falkheden et al. 1964), while a successful treatment of the disease results in the disappearance of hypervolemia (Strauch et al. 1977). We have recently demonstrated that in patients with active acromegaly the increased total body plasma volumes are accompanied by the elevated plasma ANP concentrations, whereas, in the successfully treated patients, both: total plasma volumes and plasma ANP levels do not differ significantly from these in healthy subjects (Czekalski et al. 1988b). 相似文献
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M Ardigo I Malizewsky ML Dell'Anna E Berardesca M Picardo 《Journal of the European Academy of Dermatology and Venereology》2007,21(10):1344-1350
BACKGROUND: Vitiligo is the most common pigmentary disorder with a global incidence from 0.1% to 2% in different geographical areas. Histopathology and histochemistry have shown the reduction of melanocytes in achromic patches, but microscopic changes of lesional and non-lesional skin are still not completely understood. Reflectance confocal microscopy (RCM), based on the different light reflectance index of cutaneous structures, allowed in vivo, en face microscopic evaluation of superficial skin layers with a resolution similar to skin histology. AIM: The purpose of this study was to evaluate RCM features of lesional and non-lesional skin of vitiligo patients. Moreover, re-pigmented areas were taken into consideration in order to evaluate melanocyte response to ultraviolet B (UVB) radiation. SUBJECTS AND METHODS: Sixteen patients of different phototypes affected by active non-segmental vitiligo and 10 controls were enrolled in the study. In vivo skin imaging was done using a commercially available RCM (Lucid, Vivascope 1500. Re-pigmented areas from 6 to 16 patients (after UVB narrow-band therapy) were also examined. RESULTS: Vitiligo lesions showed the disappearance of the bright rings normally seen at the dermo-epidermal junction. Moreover, non-lesional skin of vitiligo patients showed unexpected changes as the presence of half-rings or scalloped border-like features of the bright papillary rings. In re-pigmented areas after UVB narrow band therapy, the presence of activated, dendritic melanocytes was seen. CONCLUSIONS: Considering our results, and following further studies, RCM clinical applications could be used in the therapeutic monitoring and evaluation of the evolution of vitiligo. 相似文献
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Sites in the brain at which cholecystokinin octapeptide (CCK-8) acts to suppress feeding in rats: a mapping study 总被引:1,自引:0,他引:1
In this study, an examination was made of the sites in the brain of the rat at which the injection of cholecystokinin octapeptide (CCK-8) would alter food intake. Rats fasted for 24 hr received intracerebral injections of CCK-8 (1 nmol) or an equal volume of saline (0.5 microliters), into various sites in the brain through permanently implanted stainless steel cannulae. After prior acclimatisation to individual plexiglass compartments, latency to feed, as well as consumption of food and water during 0-20, 20-40 and 40-60 min after the injection, were recorded. The available food was the standard rat pellets, to which the animal otherwise had constant daily access. With this paradigm, active sites at which CCK-8 suppressed feeding were defined as sites at which consumption of food for 0-20 min was reduced by 25% or more, or the latency to feed was increased by 3 min or more after the injection of CCK-8, as compared to the effect of the injection of saline, made at the same site. Such active sites were most densely distributed in the rostral diencephalon, e.g. hypothalamus, the medial pontine area and lateral medulla, in the vicinity of the nucleus tractus solitarii (NTS). By grouping data for injections according to histologically identified sites, statistical analysis of groups of injections confirmed that these three major areas of the brain were active with regard to the suppression of feeding by CCK-8. These data suggest that CCK may not only initiate satiety messages, as a circulating hormone at peripheral sites, but also participate in the conduction of such information to the target in the brain by serving as a neurotransmitter in the lateral medulla (e.g. NTS), medial pontine area (e.g. relay station between the NTS and hypothalamus) and the lateral hypothalamus, where local release of CCK-8 after stomach loading has been observed. 相似文献