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991.
Sodium saccharin, at high doses in the diet, has been reported to cause hyperplasia of the forestomach (squamous portion of stomach), at the limiting ridge in F344 rats, in addition to its potential to induce proliferative effects on the urinary bladder epithelium. We have characterized this hyperplasia of the squamous epithelium of the forestomach at the limiting ridge in F344 and Sprague-Dawley rats given various doses of sodium saccharin for 4 to 95 wk. With increasing doses of sodium saccharin, the limiting ridge of the forestomach showed dose-related morphological changes: basal-cell hyperplasia, early papillary hyperplasia with basal-cell hyperplasia and papillary hyperplasia. Calcium saccharin in Prolab diet caused hyperplasia of the forestomach at the limiting ridge, similar to that caused by sodium saccharin. The severity of hyperplasia was influenced by the type of diet and by the strain of rats. AIN-76A diet without added sodium saccharin caused basal-cell hyperplasia in F344 rats, whereas Prolab, Purina and NIH-07 diets without added sodium saccharin had little or no effect on the forestomach. The effect of AIN-76A diet alone persisted through 95 wk of feeding without any evidence of tumour formation. In Sprague-Dawley rats, which appeared more sensitive to effects on the forestomach than F344 rats, Prolab 3200 and Purina diets without sodium saccharin caused basal-cell hyperplasia in more than half of the treated rats. The forestomach hyperplasia associated with AIN-76A or saccharin administration appears to be mild, limited in extent to the limiting ridge, and not associated with carcinogenesis. 相似文献
992.
Retinopathy of prematurity (ROP) is a vaso-proliferative disease with infiltration of the vitreous gel. Contraction of the infiltrate results in traction detachment with typical peripheral trough formation. Cryotherapy inhibits proliferation in the active stages of the disease (Stage 3, 'plus'). With development of traction detachment involving the macula (Stage 48) encircling buckling procedures should first be tried. Closed vitrectomy is considered when high retinal detachment and opacification by vitreous strands occur. The surgical technique is described. Anatomical (64%) and functional (43%) successes are reasonably high for Stage 4 cases, but disappointing (anatomical 40%, functional 16%) for Stage 5 ROP. Open funnels of detached retina fare better than closed ones. It is probably best to perform surgery not before the cicatricial stage, i.e. six months after birth. 相似文献
993.
994.
Histamine-type 2 antagonists (H2-blockers) as represented by cimentidine have been shown to adversely affect renal allograft function, particularly when coadministered
with cyclosporine, currently a major immunosuppressant. To determine whether or not a newer and more powerful H2-blocker, famotidine, would produce similar adverse effects, we assessed seven cyclosporine-treated renal allograft recipients
with regard to changes in their renal function on or off the H2-blocker over a one-week period. Neither the administration nor withdrawal of famotidine (20–40 mg/day) resulted in any significant
changes in serum creatine, BUN, urine output or cyclosporine trough levels, suggesting that famotidine can be safely administered
as an H2-blocker to cyclosporine-treated renal allograft recipients. 相似文献
995.
A 50 year old man with a two month history of upper abdominal pain and a one month history of anorexia and weight loss, presented
with icterus and evidence of peritonitis. Laparotomy revealed biliary peritonitis which had been caused by a rupture of the
fundus of the gallbladder. The common bile duct was dilated and there was a large growth in the head of the pancreas with
multiple hepatic metastases. A cholecysto-jejunostomy and gastrojejunostomy were done and the patient had an uneventful recovery. 相似文献
996.
Calcitonin gene-related peptide (CGRP) causes vasorelaxation in rat aorta involving endothelium/nitric oxide (NO)-dependent elevations of both cAMP and cGMP levels. When endothelium is removed, preincubation with exogenous NO uncovers and potentiates direct (endothelium-independent) cAMP elevations and vasorelaxations caused by CGRP. This enhancing effect of NO potentially involves elevation of cGMP and inhibition of Type III (cGMPinhibitable) phosphodiesterase, causing accumulation of cAMP. However, NO may have other actions. The aim of the present study was to determine if brain natriuretic peptide (BNP), which elevates cGMP levels independent of NO, could enhance cAMP accumulations and vasorelaxations induced by CGRP in rat aortic rings denuded of endothelium. When added separately, neither CGRP (100 nM) nor BNP (10 nM) altered cAMP levels. When added in combination, CGRP (100 nM) and BNP (10 nM) significantly elevated cAMP levels (from control of 0.95 ± 0.08 to 1.53 ± 0.09 pmol/mg protein) at 2 min. BNP (10 nM) elevated cGMP levels 10-fold at 2 min and this response was not altered by co-administration of CGRP (100 nM).Pretreatment with BNP at concentrations as low as 1 nM in endothelium-denuded aortic rings greatly enhanced the direct vasorelaxant effects of CGRP (100 nM) (from control of 0% to 57.6 ± 6.8% relaxation of phenylephrineprecontractions). Our findings indicate that BNP enhances direct (endothelium-independent) cAMP elevations and vasorelaxations caused by CGRP in rat aorta, thus supporting the concept that cGMP inhibits cAMP metabolism and enhances CGRP-induced responses in aortic smooth muscle cells. 相似文献
997.
998.
Robert K.P Chow MD Vincent C Ho MD FRCPC 《Journal of the American Academy of Dermatology》1996,34(6):1047-1060
Critical to the proper management of pyoderma gangrenosum are correct diagnosis, identification and treatment of any underlying disorder, and the proper choice of topical and systemic therapy. Many agents are available for the treatment of pyoderma gangrenosum. We review the current therapeutic options, their efficacy and side effects, and we offer some guidelines for their proper selection. 相似文献
999.
1000.
通过半年对35名7~12岁轻度碘缺乏病儿童进行补碘,并与同龄、同地的正常儿童和缺碘未补碘儿童进行比较,以观察补碘对儿童脑功能及生长发育的影响。结果发现:①补碘可使儿童碘营养状况恢复正常,尿碘值由(83.2±3.5)μg/L上升到(162.2±1.6)μg/L,血清T4、FT4I和rT3:也与正常儿童一致而与未补碘儿童有显著性差异(P<0.05).②轻度碘缺乏病儿童智商低于正常儿童(P<0.01),补碘在一定程度上改善其智商水平。③轻度碘缺乏病及补碘未能明显影响儿童的生长发育,可能与儿童总营养水平较差有关。 相似文献