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The role of growth factors and cytokines in the impaired healing of chronic leg ulcers remains uncertain. The aim of this study was to determine whether changes in the amount and location of cytokines and growth factors may be associated with impaired healing in chronic leg ulcers. Biopsies from leg ulcers of 21 patients and from normal skin of nine healthy volunteers were examined immunohistochemically for selected growth factors and cytokines. Greater staining intensity was found in keratinocytes at the edges of ulcers compared to normal skin, or skin adjacent to the ulcers. Staining at the ulcer edge was more intense in nonhealing ulcers for only vascular endothelial growth factor and platelet-derived growth factor, whereas staining in the adjacent skin was more intense for all factors in the nonhealing phase. For all factors staining was cytoplasmic, suggesting production in these areas. This study shows up-regulation of the production of cytokines and growth factors in keratinocytes of chronic leg ulcers that is greater when the ulcers are nonhealing.  相似文献   
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BACKGROUND AND OBJECTIVE: Adrenal tissue-sparing or partial adrenalectomy evolved initially for patients with bilateral synchronous adrenal surgical pathology to preserve vital adrenal volume. In the laparoscopic era, the exact criteria for performing such procedures laparoscopically have yet to be defined. Controversy exists regarding the importance of preserving the adrenal vein, main or accessory. The aim of this retrospective study was to present our short series of laparoscopic tissue-sparing adrenalectomies with vein preservation. Our main goal is not to support partial adrenalectomy as an alternative to total (this is already advocated by many surgeons) but to emphasize the vein-preserving technique. METHODS: Seven patients with peripherally located either aldosterone-producing adenomas (4 cases) or myelolipomas (4 cases) underwent laparoscopic lateral partial adrenalectomy. One patient harbored an aldosterone-producing adenoma and a myelolipoma as well. The main adrenal vein was identified and preserved in 6 patients and the accessory vein in one. RESULTS: No conversion to open adrenalectomy was necessary, and no perioperative morbidity or mortality occurred. Three adenoma patients are normotensive 44, 23, and 20 months postoperatively, while the fourth one's pressure is refractory. CONCLUSIONS: Surprisingly, total adrenalectomies preceded the partial ones, which is controversial compared with other procedures. Laparoscopic lateral partial adrenalectomy is a technically challenging tissue-sparing operation. Meticulous dissection allows preservation of the middle artery and main or accessory vein resulting in a functioning adrenal stump.  相似文献   
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BACKGROUND: Inflammatory bowel disease is associated with increased mucosal release of eicosanoids. Among these, thromboxane A2 has been proposed as a possible inflammatory mediator; its suppression may be a useful therapeutic option. METHODS: Using a tissue incubation technique, we compared release of immunoreactive thromboxane B2 by colonic biopsies from patients with ulcerative colitis, Crohn's disease and controls, and assessed the inhibitory effect of picotamide, a thromboxane synthesis inhibitor-receptor antagonist, which has been widely used in Italy for management of ischaemic heart and cerebrovascular disease. RESULTS: Increased amounts of thromboxane B2 were released from biopsies from patients with active ulcerative colitis (median 238 pg/20 min/mg wet weight (interquartile range 147- 325), n = 12) and active Crohn's disease (252 (174-450), 6) compared with those from patients with quiescent ulcerative colitis (95 (61- 140), 12) or Crohn's disease (105 (57-201), 13), or controls (136 (64- 206), 8). Incubation with picotamide at concentrations between 100 microM and 1 mM reduced thromboxane B2 release (IC50 890 microM). CONCLUSION: Since increased thromboxane A2 production may have pathogenetic importance, thromboxane synthesis inhibitor-receptor antagonists such as picotamide merit therapeutic trial in the management of inflammatory bowel disease.  相似文献   
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Follistatin and activin A production by the male reproductive tract   总被引:1,自引:0,他引:1  
Follistatin is a binding protein for the activin and inhibin family of hormones, regulating their biological activity. In the male reproductive tract, the interaction of these factors is likely to be involved in the regulation of the proliferation of several cell types. We have investigated the presence of follistatin and activin A in seminal plasma using specific immunoassays and have localized follistatin and activin/inhibin subunits in the adult human testis, prostate and seminal vesicle to establish their likely sources. High concentrations of immunoreactive follistatin were present in seminal plasma in normal men (mean 97.9 ng/ml; 1.43 ng/ml in peripheral plasma) and were similar in men with oligo/azoospermia and following vasectomy. Follistatin immunoreactivity was localized to both Leydig and Sertoli cells of the testis, and to epithelial cells of the prostate gland and seminal vesicle, which are likely to be the predominant sources of the hormone in seminal plasma. Activin A was also present in seminal plasma in normal men but was undetectable following vasectomy, thus deriving from the testis. Consistent with this finding, the betaA-subunit was immunolocalized in Sertoli and Leydig cells but was not present in seminal vesicle or prostate gland. The functional significance of the high concentrations of follistatin secreted into seminal plasma by the prostate gland and/or seminal vesicle is uncertain, but they may regulate the biological activity of testis-derived activin A and inhibin B.   相似文献   
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The aim of this study was to evaluate the medium term effects of the selective alpha1-adrenenergic- blocker terazocin on atrial natriuretic peptide (ANP) levels in patients with moderate essential hypertension. The drug was given orally for 30 days. The daily dose was 1 mg for the first 7 days, 2 mg for the next 7 days and 5 mg for the remaining period of this clinical trial. At the end of this clinical trial, plasma ANP levels increased by 16.40% despite the drop in blood pressure while left atrial and ventricular diameters remained unchanged. These findings indicate that the increase of ANP plasma levels is not the result of a mechanical load on the left cardiac chambers but the result of a pharmacological action. These observations also indicate that terazocin exerts part of its antihypertensive action by increasing ANP plasma levels.  相似文献   
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