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41.
左旋四氢巴马汀对单个豚鼠心室肌细胞钙电流的阻滞作用 总被引:4,自引:0,他引:4
AIM: To study the effect of l-tetrahydropalmatine (l-THP) on L-type calcium channel. METHODS: Patch clamp technique (whole cell recording) was used to record L-Ca2+ current in single cardiac myocyte. RESULTS: 1) l-THP 1, 10, and 100 micromol.L-1 reduced ICa-max from (999 +/- 93) pA to (700 +/- 111) pA, (582 +/- 66) pA, and (420 +/- 112) pA (n = 6, P < 0.01), respectively. 2) l-THP reduced the voltage at half-maximal inactivation (V1/2) of L-Ca2+ channel to more negative potentials by 9 mV (n = 5, P < 0.05). 3) l-THP caused both tonic and use-dependent reduction of Ca2+ current. Tonic block of l-THP on Ca2+ current was 46% +/- 8% (n = 6, P < 0.01). The degree of use dependent blocking was 13.5% +/- 2.4% (n = 6, P < 0.05) at 1 Hz, the degree increased to 44% +/- 5% (n = 6, P < 0.01) at 3 Hz. 4) l-THP delayed half-recovery time of Ca2+ channel recovery from inactivity from (94 +/- 39) ms to (170 +/- 42) ms(n = 6, P < 0.01). CONCLUSION: l-THP has a moderate inhibitory effect on L-Ca2+ current. 相似文献
42.
Population-based case-control study of CYP11A gene polymorphism and breast cancer risk. 总被引:9,自引:0,他引:9
Wei Zheng Yu-Tang Gao Xiao-Ou Shu Wanqing Wen Qiuyin Cai Qi Dai Jeffrey R Smith 《Cancer epidemiology, biomarkers & prevention》2004,13(5):709-714
The CYP11A gene encodes the cholesterol side-chain cleavage enzyme (P450scc) that catalyzes the first and rate-limiting step for the biosynthesis of sex hormones. A pentanucleotide repeat [(TAAAA)n] polymorphism in the 5' of the CYP11A gene has been reported to be related to the risk of polycystic ovary syndrome, an inherited endocrine disorder characterized by hyperandrogenemia. We investigated the association of this polymorphism with breast cancer risk in a population-based case-control study conducted among Chinese women in Shanghai. Genotype assays were completed for 1015 incident breast cancer cases and 1082 community controls. Three common alleles with 4, 6, or 8 TAAAA repeats were identified in the study population. The frequency of the 8 repeat allele was more common in cases (12.6%) than controls (8.5%) (odds ratio = 1.6, 95% confidence interval = 1.3-1.9; P < 0.0001). Compared to subjects who did not carry this allele, adjusted odds ratios were 1.5 (95% confidence interval = 1.2-1.9) and 2.9 (1.3-6.7) (P for trend, <0.001), respectively, for those who carried one and two copies of this allele. This positive association was observed in both pre- and postmenopausal women and all strata defined by major breast cancer risk factors, including years of menstruation, body mass index, and waist-to-hip ratio. The results from this study indicate that the TAAAA repeat polymorphism near the promoter region of the CYP11A gene may be an important susceptibility factor for breast cancer risk. 相似文献
43.
Horch RE Andree C Kopp J Tánczos E Voigt M Bannasch H Walgenbach KJ Dai FP Bittner K Galla TJ Stark GB 《Zentralblatt für Chirurgie》2000,125(Z1):74-78
A variety of reasons can afflict wound healing. Current research is focussed on the acceleration of wound healing by stimulating molecular processes. Gene therapy may offer completely new ways to treat chronic wounds. Possible advantages of gene therapeutic modulation of wound healing might be a long term efficiency, systemic or local regulation of gene expression and low side-effects. Current goals comprise the improvement of transfection efficiency and specificity. In vivo applications are therefore focussed on optimized inducible or even cell-type specific promotors, as well as on improved local application techniques. Studies from our laboratory demonstrate the possibility to combine modern cell culture techniques with different types of gene transfer. This enables the simultaneous grafting of manipulated cells to the wound with the continuous delivery of specific proteins of interest. Experimentally, this lead to accelerated closure of partial and full thickness animal wounds. Clinically, gene therapy for the treatment of chronic wounds seems to be a realistic goal within the next years and might be applicable for a variety of novel indications. 相似文献
44.
观察杏灵颗粒治疗冠心病心绞痛的临床疗效,共选择243例,其中治疗组153例,对照组90例。疗程为6周。治疗结果,对心绞痛疗效,两组分别为92.2%和77.8%;对心电图疗效,两组分别为62.6%和53.5%。治疗组明显优于对照组。本品对不同程度,不同类型的心绞痛患者均有较好疗效。 相似文献
45.
A case of reflex sympathetic dystrophy is presented in a 12-year-old girl with comorbid conversion disorder. Her identical twin also had a conversion disorder. This is the first reported case of coexistence of reflex sympathetic dystrophy and conversion disorder. It is important for clinicians to be aware that these conditions may coexist since the presentation of symptoms differ, even though there are shared features of treatment. 相似文献
46.
T抗原单克隆抗体法在大肠癌筛检中的应用初探 总被引:2,自引:0,他引:2
目的 探讨T抗原单克隆抗体法在大肠癌筛检中的临床价值.方法 同时采用T抗原单克隆抗体法和半乳糖氧化酶法检测207例直肠粘液中的T抗原.结果 T抗原单克隆抗体法和半乳糖氧化酶法的敏感性和特异性分别为69.2%、67.3%和64.2%、65.6%,两者的筛检价值无明显差别.结论T抗原单克隆抗体法对大肠癌筛检有较大临床价值,且操作简便. 相似文献
47.
目的了解煤工尘肺患者下呼吸道产金属内酰胺酶的铜绿假单胞菌(PA)的感染状况及其耐药特性。方法分离下呼吸道感染的煤工尘肺患者痰液标本中的PA,根据药敏试验,筛选可疑产金属内酰胺酶PA,最后依据2-巯基丙酸双纸片法鉴定产金属内酰胺酶PA。结果40株PA中共筛选出10株可疑PA,最终确定产金属内酰胺酶PA6株。这些菌株均有很强的耐药性,对亚胺培南、头孢菌素、含酶抑制剂类抗菌药物全部耐药;对阿米卡星、环丙沙星、左氧氟沙星、庆大霉素等药物部分耐药。产金属内酰胺酶PA的耐药性远强于不产金属内酰胺酶的PA。结论产金属内酰胺酶PA的耐药性很强,应加强煤工尘肺患者产金属内酰胺酶PA的检测,以利于指导治疗和控制感染。 相似文献
48.
R(+)-8-OH-DPAT (0.05, but not 0.025, 0.1, 1 mg/kg), a 5-HT(1A) receptor agonist, decreased l-3,4-dihydroxyphenylalanine (DOPA) accumulation in rat striatum following NSD-1015, an l-aromatic amino acid decarboxylase inhibitor. Amphetamine (1 mg/kg) increased striatal DOPA accumulation, an effect attenuated by R(+)-8-OH-DPAT (0.05 mg/kg). However, both amphetamine (1 mg/kg) and R(+)-8-OH-DPAT (0.05 mg/kg) decreased cortical DOPA accumulation; there were no additional decreases from their combination. Neither amphetamine (1 mg/kg), R(+)-8-OH-DPAT (0.05 mg/kg), or the combination, significantly affected DOPA accumulation in the nucleus accumbens. The significance of and possible mechanisms for these findings are discussed. 相似文献
49.
人工耳蜗植入术后植入电极的影像学检查 总被引:5,自引:0,他引:5
目的 探讨建立螺旋CT扫描及三维重建技术观察人工耳蜗植入电极方法,并比较X线摄片方法与螺旋CT扫描三维重建方法的耳蜗内电极的影像学特征及其临床应用价值。方法 18例人工耳蜗植入患者全部作术后X线摄片检查。其中9例用经眼眶前后位摄片,9例采用侧斜位60。摄片。3例患者施行术后螺旋CT扫描及内耳三维重建方法。结果 2种投射头位的X线摄片均可显示电极形态及单个电极对,可间接判断电极在耳蜗内的植入深度。螺旋CT扫描三维重建图可直观地显示耳蜗形态、电极形态及其在耳蜗内植入的深度,可清晰识别单个电极对。结论 螺旋CT扫描三维重建方法可直观观察植入电极的形态及位置,可准确判断电极在耳蜗内植入的深度,有其独特的临床应用价值。 相似文献
50.
目的:探讨穿透性角膜移植术(penetratingkeratoplasty,PKP)治疗坏死性基质角膜炎(necrotizingstromalkeratitis)的手术适应证及其临床效果。方法:按照Holland等的HSK新分类法,选择确诊坏死性基质角膜炎患者,予以局部及全身药物治疗。对病情不能控制,药物治疗无效的患者22例(23眼),其中角膜溶解穿孔3眼,用新鲜角膜组织行穿透性角膜移植术,并随访观察术后疗效。结果:随访3mo~3a,22例(23眼)中,术后视力提高者18眼,其中矫正视力达到0.1~0.5者12眼,0.05~0.1者6眼;无改善者5眼。角膜植片透明17眼,半透明2眼,植片混浊4眼,植片透明率为74%。术后3眼植片发生排斥反应,3眼原发病灶复发。2眼术后因排斥反应及原发病灶反复发作,植片完全混浊,行2次角膜移植术。结论:对坏死性基质角膜炎患者,药物保守治疗无效、角膜坏死穿孔或行将穿孔,及时用新鲜角膜组织行穿透性角膜移植术治疗,不仅能控制炎症,缩短病程,而且能保存眼球,恢复部分视力,因此具有重要临床应用价值。 相似文献