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1.
The 9-2 isozyme of 2-5 (A) synthetase has cellular proapoptotic functions that are mediated not by enzyme activity but by the Bcl-2 homology domain 3 present in its unique carboxyl-terminal region. Another proapoptotic cellular protein is Bax, whose absence in the Bax(-/-) mice causes male sterility due to abnormal sperm differentiation. In this study, we examined whether transgenic 9-2 expression can substitute for the in vivo reproductive function of Bax. To achieve this goal, a sperm-specific promoter was used to drive the expression of 9-2 in the sperm of transgenic mice. By selective cross-breeding, the transgene was transferred to Bax(-/-) mice to generate the experimental mouse line (Bax(-/-), 9-2(+/+)). The male experimental mice were sterile, and their testes maintained the structural abnormality found in Bax(-/-) mice. Thus, the male reproduction functions of Bax could not be replaced by the 9-2 isozyme of 2-5 (A) synthetase.  相似文献   
2.
Skin penetration of topically applied diclofenac is important for the treatment of rheumatic diseases and actinic keratoses. We have studied the permeation of diclofenac across human cadaver epidermis in-vitro from four lecithin vesicle formulations and a few marketed semi-solid preparations. The lecithin vesicle formulations were prepared by dissolving the lipid contents (lecithin and sodium cholate) in a 1:1 mixture of methanol-chloroform, evaporating the solvents under vacuum, and hydrating the lipid layer with the drug solution in water or 10% ethanol. The vesicles were sonicated for 5 min to reduce the vesicle size and their size and Zeta potential were characterized. The cumulative amount and maximum flux of diclofenac was 69.7+/-40.3 micrograms and 4.77+/-3.16 micrograms/hcm(2) from lecithin vesicles containing sodium cholate and 10% ethanol, and is the highest of all formulations studied. The cumulative amount and mean maximum flux obtained from other formulations were in the range of 2.46+/-1.98-29.9+/-10.1 micrograms and 0.53+/-0.46-3.61+/-0.86 micrograms/hcm(2). Based on the results, lecithin vesicles of diclofenac appear to be advantageous for the topical delivery of diclofenac.  相似文献   
3.
The present study reveals our experience in the medical management of 30 cases of progressive/malignant exophthalmos, employing costicosteroid, b-blocker, diuretic and a preparation containing proteolytic enzymes. There was encouraging improvement in terms of symptoms, proptosis and optic nerve compression, while reduction of ophthalmoplegia was not so satisfactory. However, none of the patients needed decompression surgery.  相似文献   
4.
5.
595 nm可调脉冲染料激光治疗皮肤血管异常性疾病疗效分析   总被引:1,自引:0,他引:1  
目的观察595nm可调脉冲染料激光治疗皮肤血管异常性疾病(血管畸形与血管瘤)的临床疗效。方法应用595nm可调脉冲染料激光治疗396例皮肤血管异常性疾病,观察临床疗效。结果毛细血管扩张和蜘蛛痣疗效最好,有效率为100%,其次是草莓状血管瘤,有效率为92.4%,鲜红斑痣为82.8%。面积越小,年龄越小,疗效越好(P<0.05);性别与疗效无明显差异。术中疼痛较轻,术后副作用少。结论595nm可调脉冲染料激光治疗皮肤血管异常性疾病安全性高,疗效确切。  相似文献   
6.
Karyotypes of 36 lymphoblastoid cell lines established by Epstein-Barr virus (EBV) transformation of peripheral blood lymphocytes (PBL) of eight normal individuals and 28 patients with various nonhematologic malignancies were analyzed. In seven lines (19.4%), cells with trisomy 12 were noted, with clonality in two of these lines. In two of 11 metaphases with such trisomy, chromosome 12 was involved in structural rearrangements [t(8;12)(q12;p12) and t(12;12)(q11;q24)]. No cells with trisomy 12 were observed in phytohemagglutinin (PHA)-stimulated PBL cultures of these individuals. In 250 individuals (normal and with nonhematologic malignancies) examined in our laboratory in the last 5 years, extra copies of chromosome 12 in PHA-stimulated PBL cultures were observed in only five of 23,216 cells (0.02%). There were no cases of clonality in these samples. The frequency of an extra chromosome 12 was comparable to that of the other chromosomes except 21 and X, whose frequency of occurrence was 0.08% and 0.09%, respectively. These findings should be considered random events in PHA-stimulated PBL. On the contrary, in lymphoblastoid cell lines established by EBV transformation, trisomy of chromosome 12 was the most frequent numerical abnormality. It was observed in 64.7% of all cases with chromosome gains and therefore could not be considered a random occurrence. The specificity of this phenomenon for EBV transformation is supported by the results of cytogenetic analysis of eight lymphoblastoid cell lines established by an alternative procedure in our laboratory [1]. In 400 cells analyzed not a single cell with trisomy 12 was observed. We suggest that EBV transformation might either randomly induce formation of such cells in immortalized B-cell populations or show potentially blastomogenic cells or proneness to their formation in certain individuals who could be predisposed to develop lymphoproliferative diseases, especially chronic lymphocytic leukemia (CLL) in which trisomy of chromosome 12 is the most common alteration.  相似文献   
7.
8.
Spatial analysis of (90)Sr artificial radionuclide in consequence of global fallout and Chernobyl nuclear accident has been carried out by using the point cumulative semivariogram (PCSV) technique based on 40 surface water station measurements in Keban Dam Lake during March, April, and May 2006. This technique is a convenient tool in obtaining the regional variability features around each sampling point, which yields the structural effects also in the vicinity of the same point. It presents the regional effect of all the other sites within the study area on the site concerned. In order to see to change of (90)Sr, the five models are constituted. Additionally, it provides a measure of cumulative similarity of the regional variable, (90)Sr, around any measurement site and hence it is possible to draw regional similarity maps at any desired distance around each station. In this paper, such similarity maps are also drawn for a set of distances. (90)Sr activities in lake that distance approximately 4.5 km from stations show the maximum similarity.  相似文献   
9.
膀胱癌组织P-gp,GST-π和TOPO-Ⅱ表达评估灌注化疗   总被引:1,自引:0,他引:1  
目的:探讨膀胱癌的多药耐药性(MDR),指导灌注化疗用药。方法:采用免疫组化法检测44例膀胱癌病理标本中P-糖蛋白(P-gp)、谷胱肽S转移酶(GST-π)和拓扑异构酶(TOPO—Ⅱ)的表达,评估肿瘤耐药谱。结果:①P-gp检测显示,54.5%的病例对阿毒索、丝裂毒索、长春新碱等抗生索类和生物碱类抗癌药高耐药。②GST-π检测显示仅34.1%的病例对顺铂、环磷酰胺等高耐药,而反有56.8%的病例对该类药无耐药或低度耐药。③TOPO-Ⅱ检测显示对阿霉索、柔红毒索、VP16等TOPO-Ⅱ抑制剂类抗癌药,仅13.6%的病例高度耐药,29.5%中度耐药。56.8%低度耐药。结论:检测膀胱癌MDR,了解多药耐药谱,可指导灌注化疗用药。  相似文献   
10.
We investigated the effects of activated protein C resistance (APCR), Factor V Leiden (FVL) mutation, and high lipoprotein (a) levels in 32 young patients with branch retinal vein occlusion (BRVO) vs 30 controls. No difference between patients with BRVO and controls was found with regard to APCR, FVL mutation, or lipoprotein (a) levels. These factors do not seem important in the etiology of BRVO. The authors have stated that they do not have a significant financial interest or other relationship with any product manufacturer or provider of services discussed in this article. The authors also do not discuss the use of off-label products, which includes unlabeled, unapproved, or investigative products or devices.  相似文献   
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