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51.
James F. Meschia Edward Junkins Karen J. Hofman 《American journal of medical genetics. Part A》1992,44(5):664-667
Epidermal nevi are typically congenital but rarely familial. We report on a family in which 3 relatives have systematized epidermal nevi. The propositus also has evidence of a hemangioma and a hemangioendothelioma. Peripheral blood and skin fibroblast karyotypes of the propositus did not show evidence of mosaicism. Epidermal nevi have been associated with nondermatologic pathology, involving the nervous, vascular, and skeletal systems in sporadic cases. This report demonstrates that nondermatologic pathology can be also be associated with systematized epidermal nevi in a familial setting. The apparent skipping of generations may be explained by autosomal dominant inheritance with decreased penetrance. © 1992 Wiley-Liss, Inc. 相似文献
52.
A. Saija P. Princi R. De Pasquale G. Costa G. B. De Sarro 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1992,88(1):151-157
Summary The genetically epileptic-prone rat (GEPR) is a valuable model for the study of gene-linked abnormalities involved in epilepsy. In comparison with normal Sprague-Dawley controls, we found, in GEPRs, a marked depression in local cerebral glucose utilization, widespread throughout the brain. This depression was accompanied by a significant increase of blood-brain barrier permeability and a reduction in regional blood volume. Finally GEPRs showed lower plasma levels of total triiodothyronine than normal controls. One can speculate that alterations in cerebral metabolism and microvascular regulation and thyroid hormone imbalance may be gene-linked factors involved in seizure susceptibility. 相似文献
53.
几种评价保湿产品无创性测试方法的相关性评价 总被引:4,自引:3,他引:1
目的:对测量皮肤角质层含水量和屏障功能的几种无创性皮肤测试方法进行相关性评价。方法:采用SKICON-200测定皮肤电导法、皮肤保水功能测定、TEWL测定、受试者主观评价的方法,比较某种保湿霜/精华素使用前、后皮肤角质层含水量和屏障功能的变化,并分析这些方法之间的相关性。结果:保湿霜的效果优于精华素,SKICON-200测定皮肤电导法、皮肤保水功能测定以及部分受试者临床症状和主观评价指标(如红斑、脱屑情况,皮肤滋润度的改善、皮肤细纹数量变化和皮肤弹性改善)有很好的平行关系。TEWL结果在本试验中变化不大,与上述指标没有平行关系。结论:SKICON-200测定皮肤电导法、皮肤保水功能测定适合用于保湿化妆品的功效评价。TEWL测定对于屏障功能受损的皮肤可能更敏感,对于健康皮肤使用前、后比较可作为参考指标。 相似文献
54.
目的了解表皮生长因子(epidermalgrowthfactor,EGF)对移植小肠通透性及细菌易位的作用。方法以Wistar大鼠为供体,SD大鼠为受体行异位全小肠移植,并以环孢素A(CsA,6mg.kg-1.d-1,im)抑制排斥反应。表皮生长因子组(EGF组)用微量输液泵持续均匀输入EGF200μg.kg-1.d-1;对照组输入等量生理盐水。第7天以乳果糖及甘露醇行移植肠灌注并收集尿液行高效液相色谱仪分析乳果糖及甘露醇含量,第8天采集移植肠系膜淋巴结及门静脉血行细菌培养。结果对照组尿液中乳果糖含量[(0.093±0.008)vs(0.015±0.002),P=0.0001]及乳果糖/甘露醇比值[(0.132±0.021)vs(0.020±0.005),P=0.0001]明显高于基准,EGF组乳果糖含量[(0.043±0.008)vs(0.015±0.002),P=0.0054]及乳果糖/甘露醇比值[(0.060±0.017)vs(0.020±0.005),P=0.0029]也较基准增加,EGF组乳果糖含量[(0.043±0.008)vs(0.093±0.008),P=0.0067)及乳果糖/甘露醇比值[(0.060±0.017)vs(0.132±0.021),P=0.0116]显著低于对照组。EGF组移植肠系膜淋巴结细菌阳性率为10%,对照组阳性率为60%,明显高于EGF组(P=0.028)。EGF组与对照组门静脉血培养阳性率比较差异无统计学意义(P>0.05)。结论本研究提示EGF能够降低同种移植小肠的通透性及细菌易位率,改善肠黏膜屏障功能。 相似文献
55.
Abstract The study of animal lectins and glycoconjugates has become an important area of research in biomedical sciences, as these molecules are believed to play important roles in a variety of biological processes. This report describes a study of the expression of an animal lectin, IgE-binding protein (?BP), also known as Mac-2 and CBP35, in human skin. We have analyzed cultured human keratinocytes as well as normal human skin and a number of epidermal neoplasms, by immunoblotting. immuno-fluorescence and immunohistochemistry. We showed that ?BP is expressed in human keratinocytes, hair follicles, sebaceous and sweat glands. We found that cBP expression retains in various epidermal neoplasms, including basal cell carcinoma, squamous cell carcinoma and keratoacan-thoma, although the level of expression appears to be reduced as compared to normal epidermis. The immunohistochemical analysis also suggests that the level of ?BP expression appears to be dependent on the degree of cellular differentiation of keratinocytes. 相似文献
56.
The effects of treatment with a bombesin receptor antagonist [D-Tpi6, Leu13 psi (CH2NH) Leu14]BN(6-14)(RC-3095) and the combination of an agonist of luteinizing hormone-releasing hormone [D-Trp6]-LH-RH and somatostatin analog D-Phe-Cys-Tyr-D-Trp-Lys-Val- Cys-Trp-NH2 (RC-160) were studied in nude mice bearing xenografts of the hormone-dependent human prostate tumor PC-82. During the 5 weeks of treatment, tumor growth was decreased in all treated groups compared with controls. Bombesin antagonist RC-3095 and the combination of [D-Trp6]-LH-RH and RC-160 caused a greater inhibition of tumor growth than [D-Trp6]-LH-RH or RC-160 alone as based on measurement of tumor volume and percentage change in tumor volume. The largest decrease in tumor weight was also seen in the groups treated with the bombesin antagonist and with the combination of RC-160 and [D-Trp6]-LH-RH. Serum prostatic-specific antigen levels were greatly decreased, and insulin-like growth factor I (IGF-I) as well as growth hormone levels were reduced in all treated groups. Specific binding sites for [D-Trp6]-LH-RH, epidermal growth factor (EGF), IGF-I, and somatostatin (SS-14) were found in the tumor membranes. Receptors for EGF were significantly down-regulated by treatment with the bombesin antagonist or RC-160. Combination of LH-RH agonists with somatostatin analog RC-160 might be considered for improvement of hormonal therapy for prostate cancer. The finding that bombesin antagonist RC-3095 inhibits the growth of PC-82 prostate cancer suggests the merit of further studies to evaluate the possible usefulness of antagonists of bombesin in the management of prostatic carcinoma. 相似文献
57.
外源性表皮生长因子(或生长抑素)能促进(或抑制)胰腺癌细胞的增殖。胰腺癌细胞增殖速率的高低与细胞膜脂质饱和度的降、升;与膜胰岛素受体数量的增减密切相关。测定细胞膜脂质饱和度和胰岛素受体数量,是判断胰腺癌增殖状态的灵敏指标,有一定临床价值。 相似文献
58.
George M. Smith H.David Shine 《International journal of developmental neuroscience》1992,10(5):387-392
Tight junctions may play an important role in maintaining the integrity of the blood-brain barrier. These junctions can be individually visualized using electron microscopy but no current technique is able to provide a more global picture of the presence and density of tight junctions in central nervous system tissue. We used an antibody that recognizes a high molecular weight protein (ZO-1) associated with tight junctions, to identify these specialized junctions within the rat brain and spinal cord. Immunofluorescent labeling showed a network of tight junctions between cells in the brain vasculature, leptomeninges and choroid plexus, and between tanycytes lining the floor of the third ventricle and the central canal of the spinal cord. Anti-ZO-1 labeled the majority of cells associated with the blood-brain barrier and may prove a useful marker, possibly in conjunction with functional dye studies, in evaluating the anatomical and functional integrity of the blood-brain barrier. 相似文献
59.
MN Tabrizi† C Chams-Davatchi† N Esmaeeli† P Noormohammadpoor† F Safar† H Etemadzadeh† HA Ettehadi‡ F Gorouhi† 《Journal of the European Academy of Dermatology and Venereology》2007,21(1):79-84
BACKGROUND: Pemphigus vulgaris (PV) is a severe blistering disease involving the skin and mucous membranes. The most common causes of death in these patients are adverse effects of drugs, and infection. Skin lesions are one of the important sources of infection. Thus, any local treatment that could reduce healing time of lesions and consequently reduce the total dosage of drugs needed to treat is favourable. OBJECTIVE: To evaluate the efficacy of epidermal growth factor (EGF) in reducing healing time of lesions in patients with pemphigus vulgaris. METHODS: In this randomized, double-blind, within-patient, left/right, controlled trial, 20 hospitalized patients with pathologial and immunohistologial (direct and indirect immunoflourecence) proven pemphigus vulgaris (PV) were chosen. In addition, all patients had at least one appropriate pemphigus lesion on each side of the body that had not healed after 2-week systemic therapy and sterile saline washing. EGF (10 microg/g) in 0.1% silver sulfadiazine cream vs. 0.1% silver sulfadiazine cream alone was applied randomly on one side of the body. RESULTS: Kaplan-Meier survival analysis suggested that median time to heal with application of EGF plus silver sulfadiazine cream was 9 days, in comparison with 15 days for silver sulfadiazine cream alone (log-rank test, P=0.0003). No intervention-related adverse effect was observed during the study. CONCLUSIONS: EGF can significantly reduce healing time of skin lesions in patients with pemphigus vulgaris, at least when this cream base is applied (Cochrane skin group identifier: CSG20). 相似文献
60.
目的评价定量检测放射性血脑屏障(BBB)破坏的不同方法,探讨碱性成纤维细胞生长因子(bFGF)对放射性BBB破坏的保护作用。方法60只急性放射性脑损伤模型大鼠(直线加速器6MeV电子束单次照射25Gy)分为单纯照射组和照射前尾静脉注射bFGF组(250ng/kg),并设未照射对照组;分别于照射后2、7和30d采用脑干-湿重法检测脑含水量,并用单次静脉注射3mg/kg伊文氏蓝(EB)后脑组织的EB含量法评估BBB破坏情况。结果照射后脑组织含水量和EB含量均较对照组明显增高,注射bFGF组脑组织含水量和EB含量均低于单纯照射组(P〈0.05)。受照后不同日期的脑组织EB含量差异有统计学意义(P〈0.05),而脑含水量差异没有统计学意义。结论注射EB后检测脑组织,浓度法较干湿重法测脑含水量能更好地反映BBB的破坏情况;bFGF对受照后BBB破坏有保护作用。 相似文献