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991.
目的 观察自体角膜缘干细胞移植联合丝裂霉素C治疗复发件翼状胬肉的疗效.方法 将58例(62眼)复发性翼状胬肉患者随机分为2组,治疗组(32例,35跟)采用角膜缘于细胞移植联合应用丝裂霉素C;对照组(26例,27眼)单纯采用角膜缘干细胞移植术治疗.术后随访6~30个月并比较疗效.结果 治疗组1眼冉复发,再复发率2.86%;对照组5眼再复发,再复发率18.52%,两组差异具有统计学意义(P<0.05).治疗组角膜创面上皮平均愈合时间为(8.34 ±2.38)d,对照组为(7.21±2.55)d,差异无统计学意义(P>0.05).两组均未发现严重并发症.结论 角膜缘干细胞移植联合应用丝裂霉素C治疗复发性翼状胬肉再复发率低,并发症少,为复发性翼状胬肉安全和有效的治疗方法 .  相似文献   
992.
The possible characteristics of spinal interaction between sildenafil (phosphodiesterase 5 inhibitor) and morphine on formalin-induced nociception in rats was examined. Then the role of the opioid receptor in the effect of sildenafil was further investigated. Catheters were inserted into the intrathecal space of male Sprague-Dawley rats. For induction of pain, 50 µL of 5% formalin solution was applied to the hind-paw. Isobolographic analysis was used for the evaluation of drug interaction between sildenafil and morphine. Furthermore, naloxone was intrathecally given to verify the involvement of the opioid receptor in the antinociception of sildenafil. Both sildenafil and morphine produced an antinociceptive effect during phase 1 and phase 2 in the formalin test. The isobolographic analysis revealed an additive interaction after intrathecal delivery of the sildenafil-morphine mixture in both phases. Intrathecal naloxone reversed the antinociception of sildenafil in both phases. These results suggest that sildenafil, morphine, and the mixture of the two drugs are effective against acute pain and facilitated pain state at the spinal level. Thus, the spinal combination of sildenafil with morphine may be useful in the management of the same state. Furthermore, the opioid receptor is contributable to the antinocieptive mechanism of sildenafil at the spinal level.  相似文献   
993.
In order to establish referential hematological parameters, blood samples were taken from 100 healthy specimens of the Argentine tegu lizard (Tupinambis merianae) by means of venipuncture of ventral coccigeal vein. The determination of red blood cells, leukocyte and thrombocyte count, hematocrit, hemoglobin concentration, hematometric index and differential leukocyte count were performed, and compared with other saurian species. No statistically significant changes were observed as function as sex and age (p > 0.01). During winter, high values of red blood cell counts, hematocrit and hemoglobin were observed (p < 0.01), while in summer significantly increased leukocyte and thrombocyte counts were observed (p < 0.01). The differential leukocyte counts were not affected by the studied factors.  相似文献   
994.
Killer immunoglobulin-like receptor (KIR) genes can regulate the activation of NK and T cells upon interaction with HLA class I molecules. Hepatitis B virus (HBV) infection has been regarded as a multi-factorial disorder disease. Previous studies revealed that KIRs were involved in HCV and HIV infection or clearance. The aim of this study was to explore the possibility of the inheritance of KIR genotypes and haplotypes as a candidate for susceptibility to persistent HBV infection or HBV clearance. The sequence specific primer polymerase chain reaction (SSP-PCR) was employed to identify the KIR genes and pseudogenes in 150 chronic hepatitis B (CHB) patients, 251 spontaneously recovered (SR) controls, and 412 healthy controls. The frequencies of genotype G7 M, FZ1 increased in CHB patients compared with healthy control subjects. The frequency of genotype AH was higher in SR controls than that in both CHB patients and healthy controls. The carriage frequencies of genotype G and AH were higher; while, the frequencies of AF and AJ were lower in SR controls than those in healthy control subjects. The frequency of A haplotype was lower, whereas, the frequency of B haplotype was higher in CHB patients and SR controls than those in healthy controls. In healthy controls, haplotype 4 was found lower compared with that in CHB patients and SR controls and the frequency of haplotype 5 was higher in SR controls than that in other two groups. Based on these findings, it seems that the genotypes M and FZ1 are HBV susceptive genotypes; AH, on the other hand, may be protective genotypes that facilitate the clearance of HBV. It appears that the haplotype 4 is HBV susceptive haplotype, whereas, haplotype 5 may be the protective haplotype that facilitates the clearance of HBV. Cellular & Molecular Immunology. 2008;5(6):457-463.  相似文献   
995.
帕金森病大鼠模型额叶皮质的代谢及形态改变   总被引:5,自引:0,他引:5  
目的:探讨帕金森病中大脑额叶皮质的形态及代谢改变。方法:大鼠实验组于6-OHDA毁损后用BIOSPEC47/30磁共振波谱仪(4.7T),采用点分辨波谱法对双侧额叶皮质行H-MRS检测,分析该区N-乙酰天门冬氨酸/肌酸(NAA/Cr)和胆碱/肌酸(Cho/Cr)比值的变化,并用电镜观察该区神经元及突触的形态变化。结果:实验组大鼠损毁侧额叶皮质.NA.A/Cr比值显著低于对侧,对照组两侧无显著差别;Cho/Cr比值在两组的两侧相比均无显著差别。电镜观察显示:损毁侧额叶皮质的突触数量较对侧减少,突触前、后膜和突触小泡结构异常,典型突触结构消失,树突棘出现大片低电子密度区,细胞器消失。结论:帕金森病大鼠模型损毁侧额叶皮质内存在神经元缺失或突触数量的减少,突触结构异常及功能异常。  相似文献   
996.
目的 比较相同发育阶段中枢神经系统不同部位来源的神经干细胞在体外的生长特性。方法 胚胎小鼠(E14)于无菌条件下分别分离并收集皮层、纹状体、间脑、中.后脑和脊髓,各部分制备成单细胞悬液,接种在添加有纤维细胞生长因子(FGF)的无血清培养液内,神经干细胞克隆生成后,经免疫细胞化学方法鉴定细胞特性,并在相同条件下进行传代,相差显微镜下观察克隆生成和细胞的迁移特性。结果 在添加有纤维细胞生长因子的无血清培养液中,少量接种的单个细胞会增殖并形成悬浮于细胞培养液中的细胞克隆。这些克隆具有生成新克隆并分化成神经元和胶质细胞的能力。在相同发育阶段,皮层、纹状体、间脑均可生成悬浮的克隆,其中皮层生成的速度最快,纹状体、间脑较慢,中.后脑、脊髓生成克隆的速度最慢;生成克隆后,皮层克隆的贴壁能力最差,贴壁的克隆少有细胞从其底部迁出,纹状体、间脑克隆较易贴壁,贴壁克隆底部有明显的细胞迁出,中.后脑、脊髓生成的克隆不易悬浮,很快贴壁,在贴壁克隆的底部有大量的细胞迁出。结论 在无血清培养液中,神经干细胞可在体外增殖、传代并分化生成神经元和胶质细胞,不同部位来源的神经干细胞在体外生成克隆的速度和细胞迁移性不同,这可能同体内特定部位细胞的发育特性有关。  相似文献   
997.
A locus for spondylocarpotarsal synostosis syndrome at chromosome 3p14   总被引:3,自引:0,他引:3  
Spondylocarpotarsal synostosis syndrome is a rare autosomal recessive disorder characterised by vertebral fusions, frequently manifesting as an unsegmented vertebral bar, as well as fusions of the carpal and tarsal bones.

In a study of three consanguineous families and one non-consanguineous family, linkage analysis was used to establish the chromosomal location of the disease gene. Linkage analysis localised the disease gene to chromosome 3p14. A maximum lod score of 6.49 (q = 0) was obtained for the marker at locus D3S3532 on chromosome 3p. Recombination mapping narrowed the linked region to the 5.7 cM genetic interval between the markers at loci D3S3724 and D3S1300. A common region of homozygosity was found between the markers at loci D3S3724 and D3S1300, defining a physical interval of approximately 4 million base pairs likely to contain the disease gene.

Identification of the gene responsible for this disorder will provide insight into the genes that play a role in the formation of the vertebral column and joints.

  相似文献   
998.
目的 探讨不同剂量生长激素 (GH)在体外受精 -胚胎移植 (IVF -ET)中 ,对低反应患者超排卵周期的作用。方法 前一IVF周期卵巢低反应的患者 30例 ,她们在前一周期采用促性腺激素释放激素激动剂 (GnRH -a)和促性腺激素(Gn)治疗 ,本周期采用GnRH -a、Gn、GH(两种不同剂量 )治疗 ,比较两种不同剂量生长激素的作用。结果 两种剂量生长激素均可提高受精率 ,增加优质胚胎数 ,提高妊娠率 ,且不同剂量生长激素间的作用无显著差异。结论 生长激素在IVF超排卵中有辅助作用 ,且不同剂量作用无显著差异  相似文献   
999.
目的:描述我国六地区四种特殊职业人群的饮酒情况及与饮酒相关问题发生率,并与普通人群相比较。方法:抽样调查,使用定式问卷及DSM-II-R诊断标准向9800名受试者(18-65岁)调查饮酒情况、饮酒相关的社会、心理和躯体问题。结果:男女及总饮酒率分别为86.2%、44.1%和74.1%,年平均饮酒量分别为8.25、0.56及6.00升纯酒精。酒依赖的男性、女性和总的时点患病率分别为10.545%、0.141%和7.561%,急性酒中毒的半年患病率分别为7.916%、0.071%和5.668%。与普通人群相比,四种特殊职业人群的饮酒率、年饮酒量和与饮酒相关的损害均较高。结论:职业环境是影响饮酒的重要因素之一,处于特殊环境的人群是出现酒问题的高危人群。  相似文献   
1000.
The development is expected of scaffold biomaterials that feature a shape-maintaining property in addition to high porosity and large pores that cells can easily invade. To develop a new biodegradable scaffold biomaterial reinforced with a frame, synthesized carbonate apatite (CO3Ap) was mixed with neutralized collagen gel, and the CO3Ap–collagen mixtures were lyophilized into sponges in a porous hydroxyapatite (HAp) frame ring. X-ray diffraction and Fourier transform infrared spectroscopy (FT-IR) analyses together with chemical analysis indicated that the synthesized CO3Ap had a crystalline nature and a chemical composition similar to that of bone. Scanning electron microscope (SEM) observation showed that the CO3Ap–collagen sponge had a sui pore size for cell invasion. In proliferation and differentiation experiments with osteoblasts, alkaline phosphatase and osteopontin activity were clearly detected. When these sponge–frame complexes with bone morphogenic protein (rh-BMP2) were implanted beneath the periosteum cranii of rats, significant new bone was created at the surface of the periosteum cranii after 4 weeks of implantation. These reinforced CO3Ap–collagen sponges with rh-BMP2 are expected to be used as hard tissue scaffold biomaterials for the therapeutic purpose of the rapid cure of bone defects.  相似文献   
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