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41.
Henry Ho‐Lung Chan 《Clinical & experimental optometry》2005,88(6):410-414
The first‐order kernel analysis in multifocal electroretinogram (mfERG) using low contrast stimulation is suggested as a way to detect the inner retinal responses in animal studies. In this case report, this protocol is applied to human patients with glaucoma to demonstrate the possibility of using mfERG as a tool to detect glaucomatous damage. Two patients with glaucoma were recruited and had mfERG measurements with the 103‐scaled hexagonal stimulus pattern at low (50 per cent) contrast. Their responses were analysed and compared with those from normal subjects with the mfERG measured under the same condition. In the normal subjects, there were obvious oscillatory components on the ascending and descending limbs of the first‐order kernel response to 50 per cent contrast. In the glaucomatous patients, the oscillatory component on the descending limb was obviously diminished. In addition, this component was significantly diminished in the quadrant with a glaucomatous visual field defect. This suggests that the low‐contrast stimulation condition in mERG measurement may provide a good way to detect glaucomatous damage and this may help in clinical diagnosis of glaucoma. 相似文献
42.
Sheng-Chieh Lin Shyh-Dar Shyur Yi-Chun Ma Li-Hsin Huang Hung-Chang Lee Wen-I Lee 《台湾医志》2005,104(6):421-426
X-linked hyper-immunoglobulin M (IgM) syndrome (XHIGM) is a rare genetic primary immunodeficiency disease caused by mutations of the CD40 ligand (CD40L) gene with normal or elevated levels of IgM and markedly decreased serum IgG, IgA, and IgE. Liver disease may occur as a clinical manifestation in XHIGM. This complication appears to increase with age. We report an 18-year-old male patient who had recurrent episodes of acalculous cholecystitis (AC) and sclerosing cholangitis (SC). The diagnosis of XHIGM was confirmed by the finding of CD40L expression < 1% of normal and a tyrosine 169 asparaginase (t526a) mutation in exon 5 (the tumor necrosis factor domain) of the CD40L gene. The patient had direct hyperbilirubinemia (direct bilirubin 5.5 mg/dL, total bilirubin 8.7 mg/dL), cholestasis (alkaline phosphatase 1133 U/L, gamma-glutamyl transferase 1019 U/L) and elevated transaminases (aspartate aminotransferase 70 U/L, alanine aminotransferase 101 U/L). Findings on abdominal ultrasound and abdominal computed tomography were compatible with AC. After the fourth episode of cholecystitis, cholecystectomy and liver biopsy were performed. Operative cholangiography revealed poor opacification of the hepatic duct and proximal common bile duct; the upstream intrahepatic bile ducts were not visualized. The biopsy specimen showed marked fibrosis of the portal areas. Enterococcus species was cultured from the bile. Children or adolescents with recurrent AC and SC should be evaluated for an underlying immunodeficiency syndrome such as XHIGM. 相似文献
43.
Single or combined monoclonal antibodies (McAbs) Zh53, Zh820, and Zh2-1 have been used to eliminate malignant clonogenic cells from human bone marrow. The test of cytotoxicity showed that all of these McAbs could express high specific cytotoxic action against HL-60 cells and were selectively complement-dependent cytotoxic to various types of fresh leukemic cells. Clonogenic assay detected that single treatment with antibody and rabbit complement (RC) could reduce clonogenic units of HL-60 cells by more than 2 logs and two treatments reduced clonogenic units by more than 4 logs. However, combination of 2 McAbs could reduce clonogenic units by 4-5 logs. The data suggest that multiple treatments with McAbs and RC or a combination of 2 McAbs are more effective than a single treatment in eliminating clonogenic tumor cells. Treatment of normal human bone marrow with Zh53, Zh2-1 and RC did not produce a loss of normal CFU-GM, but treatment with Zh820 reduced the clonic units of normal CFU-GM by 24%.
相似文献
44.
灯盏花素注射液对大鼠脑缺血-再灌注脑损害的凋亡抑制作用 总被引:9,自引:0,他引:9
目的:研究灯盏花素(Bre)对大鼠脑缺血-再灌注引起脑损伤的保护作用。方法:实验选用40只雄性Wistar大鼠,大鼠被随机分成5组:假手术组、对照组、硫酸镁(Mg-SO4)治疗组、灯盏花素治疗和组。自大鼠颈总动脉插入尼龙线栓栓塞大脑中动脉,造成大脑缺血,拔出线栓实现再灌注。脑缺血10min后给予75mg/kg和50mg/kgBre及30mg/kgMgSO4,分别于脑缺血1h,再灌注2h,5h和23h分别进行神经病学评分,并于脑缺血1h,再灌注23h时测定脑梗死面积,用TUNEL法和免疫组化法分别检测脑组织凋亡细胞和Caspase-3阳性细胞的变化。结果:灯盏花素降低脑缺血-再灌注大鼠神经病学评分,缩小脑梗死面积,降低脑组织凋亡细胞和Caspase-3阳性细胞数量,其作用强于硫酸镁。结论:灯盏花素通过抑制细胞凋亡可显著保护大脑缺血-再灌注引起的脑损伤,其作用优于单用硫酸镁。 相似文献
45.
E. Wieczerzak E. Jankowska S. Rodziewicz‐Motowido A. Giedo J. giewka Z. Grzonka M. Abrahamson A. Grubb D. Brmme 《Chemical biology & drug design》2005,66(Z1):1-11
Abstract: We have designed and synthesized a new series of azapeptides which act as potential inhibitors of cathepsin B and/or cathepsin K. Their structures are based upon the inhibitory sites of natural cysteine protease inhibitors, cystatins. For the synthesized azapeptides, the equilibrium constants for dissociation of inhibitor–enzyme complex, Ki, were determined. Comparison of these values indicated that all of the azainhibitors act much stronger toward cathepsin B. Z‐Arg‐Leu‐His‐Agly‐Ile‐Val‐OMe ( 7 ) proved to be approximately 500 times more potent for cathepsin B than for cathepsin K. To be able to explain the obtained experimental values we used the molecular dynamics procedures to analyze the interactions between cathepsin B and compound 7 . We also determined the structure of the most potent and selective cathepsin B azainhibitor by means of NMR studies and theoretical calculations. In this report, we describe SAR studies of azapeptide inhibitors indicating the influence of the conformational flexibility of the examined compounds on inhibition of cathepsins B and K. 相似文献
46.
47.
目的探讨NO合成底物左旋-精氨酸(L-Arg)对兔局灶脑缺血后血管再生和脑细胞凋亡的影响。方法兔局灶脑缺血后应用L-Arg,流式细胞仪定量分析细胞凋亡率的变化,CD34免疫组织化学测脑组织微血管密度(MVD),脑组织含水率评价脑水肿。结果与对照组比较,L-Arg组脑细胞凋亡率明显减少(8.72±2.62 vs 16.62±2.82,P<0.01),同时脑组织MVD却明显增加(1.21±0.43 vs 0.69±0.22,P<0.01)。结论外源性L-Arg可减少缺血后脑细胞凋亡并促进缺血后血管再生,对局灶脑缺血具有重要的神经保护作用。 相似文献
48.
中药内外并用抗尖锐湿疣复发的临床研究 总被引:5,自引:1,他引:4
目的:观察中药消疣丸/消疣擦剂内服外用防止尖锐湿疣复发的作用.方法:应用免疫学方法,检测患者治疗前后外周血T淋巴细胞亚群CD3、CD4、CD8的百分率和CD4/CD8的比值.结果:局部消除疣体后中药消疣丸/消疣擦剂内服外用对防止尖锐湿疣复发有显著疗效,痊愈率为99.66%,复发率为3.33%,与对照组相比有显著差异(P〈0.05).结论:中药内服外用抗尖锐湿疣复发效果好。 相似文献
49.
50.
1 The internal anal sphincter (IAS) has a spontaneous tone and is the main contributor to the maintenance of faecal continence. The spontaneous resting tone exhibited by the sphincter can be modified by neurotransmitters from the autonomic and enteric nervous systems. 2 In this review, the influence of the sympathetic and parasympathetic nervous systems on IAS tone are discussed and the putative roles of nitric oxide, carbon monoxide, vasoactive intestinal peptide and adenosine triphosphate in non‐adrenergic non‐cholinergic transmission are considered. 3 Faecal incontinence is a common condition that places a heavy financial burden on the health service and severely affects patients’ quality of life. Resting anal pressure is reduced in patients with faecal incontinence and agents that increase sphincter tone tend to relieve symptoms. The results of clinical studies of the use of phenylephrine to treat faecal incontinence are reviewed. 4 It is concluded that the IAS is a potential target for drug development for the treatment of faecal incontinence. 相似文献