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41.
目的研究与细胞因子信号转导等相关的病理基因在妊娠高血压综合征(妊高征)胎盘组织中的表达变化.方法采用分别包含220余种人类细胞因子相关基因或人类环境激素相关基因cDNA片段的基因芯片,检测严格配伍的正常和妊高征胎盘组织中基因表达谱的差异.结果一些疾病相关基因(GenBank:U82828、X15183)在妊高征患者胎盘中的表达高于正常,另外一些与基因表达调控有关的转录因子基因(GenBank:AL022312、M15990、U15009、L49380等)也表达增强.此外,妊高征胎盘中与细胞因子信号转导有关的大多数受体/激酶表达增强,例如GenBank登录号为M76125、U73531、L76191、L06139、AF035121、M23379、U43195等基因.结论细胞因子信号转导相关基因等的表达增强提示细胞因子的功能活跃,进一步说明胎盘局部细胞因子水平的变化与妊高征的病理发生密切相关. 相似文献
42.
【目的】比较宫颈Bishop评分和宫颈胰岛素样生长因子结合蛋白 1(IGFBP 1)检测在妊娠晚期气囊助产中的临床意义。【方法】将妊娠晚期有引产指征的 15 0例初产妇随机分成 3组 ,每组 5 0例。A组在气囊助产前使用宫颈IGFBP 1检测作为引产时机预测 ,B组在气囊助产前使用宫颈Bishop评分作为引产时机预测 ,C组则单纯催产素引产同时使用宫颈Bish op评分作为引产时机预测。【结果】总引产时间、潜伏期、活跃期、第一产程、第二产程 ,A、B两组较C组短 (P <0 0 1) ;A组总引产时间较B组短 (P <0 0 5 ) ;A组潜伏期、活跃期、第一产程、第二产程的较B组短 ,但差别无统计学意义 ;阴道分娩率A组 >B组 >C组 ,剖宫产率A组 相似文献
43.
正常妊娠和妊娠高血压综合征孕妇血清脂质的过氧化作用 总被引:1,自引:0,他引:1
目的 探讨脂质过氧化作用在正常妊娠时的生理和妊娠高血压综合征 (妊高征 )时的致病机制。方法 应用美国CIBA 5 6 0全自动生化分析仪及 72 2分光光度计对正常孕妇 178例、妊高征孕妇 2 4 6例、正常晚期孕妇 178例和正常未孕妇女 6 2例 (对照组 )的血清中SOD ,LPO ,NO及总抗氧化能力进行测定比较。结果 正常妊娠晚期的SOD活性及LPO水平高于非妊娠妇女 (P <0 .0 5 ) ,妊高征患者中脂质过氧化物水平显著高于同期正常妊娠水平 (P <0 .0 5 ) ,而且随病情严重程度而升高。妊高征患者NO水平低于正常妊娠妇女 (P <0 .0 5 )。NO水平随妊高征病情进展而逐渐降低。结论 SOD ,LPO ,NO的合成、释放在妊高征的病理变化中起重要作用 相似文献
44.
Summary. Superoxide dismutase-like activity (SOD-like), isoenzyme lactate dehydrogenase-C4 (LDH-C4) and NADH-diaphorase activities in spermatozoa have been investigated from 58 normozoospermic and 27 oligozoospermic men. Significantly higher SOD-like, LDH-C4 and diaphorase activities ( P <0.01, P <0.005 and P <0.0001, respectively) were detected in spermatozoa from oligozoospermic men, compared to the activities found in normozoospermic samples. SOD-like activity (mean±SE) in oligozoospermic samples amounted to 8.3±1.6 U 10−8 spermatozoa, while in spermatozoa in normozoospermic men with a sperm concentration above 20 million of spermatozoa per ml amounted to 4.2±0.5 U 10−8 . There was a close correlation between the SOD-like activity and biochemical indicators of the presence of residual cytoplasm i.e. isoenzyme LDH-C4 and NADH-diaphorase (r = 0.53 and r = 0.66 in normozoospermic and r = 0.63 and r = 0.54 in oligozoospermic men, respectively). A positive relationship between SOD-like activity and experimentally-induced lipid peroxidation was detected in 54 infertile men (r = 0.30; P <0.05). These findings suggest that a higher level of superoxide dismutase-like activity may reflect a defect in the development or maturation of spermatozoa and, thereby, a decreased fertility potential. Hence, determination of SOD-like activity may give information on the state of maturity of human spermatozoa, while its role in the antioxidative protection remains to be determined. 相似文献
45.
46.
Istvn . Mrocz Kullervo Hynynen HLkon Gudbjartsson Sharon Peled Vincent Colucci Ferenc A. Jlesz 《Journal of magnetic resonance imaging : JMRI》1998,8(1):136-142
The aim of this study was to investigate a potential technique for image-guided minimally invasive neurosurgical interventions. Focused ultrasound (FUS) delivers thermal energy without an invasive probe, penetrating the dura mater, entering through the cerebrospinal fluid (CSF) space, or harming intervening brain tissue. We applied continuous on-line monitoring by MRI to demonstrate the effect of the thermal intervention on the brain tissue. For this, seven rabbits had a part of their skull removed to create access for the FUS beam into the brain through an acoustic window of 11 mm in diameter. Dura was left intact and skin was sutured. One week later, the rabbits were sonicated for 3 seconds with 21 W acoustic power, and the FUS focus was visualized with a temperature-sensitive T1-weighted MRI pulse sequence. The tissue reaction was documented over 7 days with T2-weighted images of the brain. The initial area of the central low signal intensity in the axial plane was .4 ± .3 mm2, and for the bright hyperintensity surrounding the lesion, it was 2.3 ± .6 mm2 (n = 7). In the coronal plane, the corresponding values were .4 ± .1 mm2 and 3.4 ± .9 mm2 (n = 5). The developing brain edema culminated 48 hours later and thereafter diminished during the next 5 days. Histology revealed a central necrosis in the white matter surrounded by edematous tissue with inflammatory cells. In summary, the image-guided thermal ablation technique described here produced a relatively small lesion in the white matter at the targeted location. This was accomplished without opening the dura or the need for a stereotactical device. MRI allowed on-line monitoring of the lesion setting and the deposition of thermal energy and demonstrated the tissue damage after the thermal injury. 相似文献
47.
48.
目的为探讨遗传因素在鄂西苗族氨基糖甙类抗生素致聋(AAID)发生中的作用,从分子水平研究该病的发病机制.方法对鄂西苗族部分家系及医学散发病例通过问卷调查和进行听力测试,确诊为AAID的82名患者,采外周血作PCR-RFLP分析,对照组为正常苗族50名.结果82名患者中27例具有mtDNA1555A→G异质性突变,10例为均质性突变,该位点突变率为45.1%,其中异质性突变占72,9%,而对照组均无此突变.结论mtDNA1555A→G突变是鄂西苗族个体对氨基糖甙类抗生素易感致聋的分子基础,异质性突变在苗族AAID中发生率较高. 相似文献
49.
Messinis IE 《Human reproduction (Oxford, England)》2005,20(10):2688-2697
Ovulation induction is the method for treating anovulatory infertility. For patients with hypogonadotrophic hypogonadism, the treatment involves administration of both FSH and LH, while HCG is injected for follicle rupture. Pulsatile GnRH has the same effectiveness as gonadotrophins and the advantage of the low multiple pregnancy rate. In polycystic ovary syndrome (PCOS), the first treatment choice is clomiphene citrate. With this drug, in properly selected patients, the cumulative pregnancy rate approaches that of normal women. Low-dose protocols of FSH are the second line of treatment, effective in inducing monofollicular development. Laparoscopic ovarian drilling can be an alternative but not as a first choice treatment in clomiphene-resistant patients. Other treatments, such as pulsatile GnRH and GnRH agonists, are hardly used today in PCOS. However, in obese women with PCOS, weight loss and exercise should be recommended as the first line of therapy. Newer agents including aromatase inhibitors and insulin sensitizers, although promising, need further evaluation. 相似文献
50.
The present study aimed at investigating the spatial variability of skin temperature (T
sk) measured at various points on the hand during convective and cold contact exposure. A group of 8 subjects participated in a study of convective cooling of the hand (60 min) and 20 subjects to contact cooling of the finger pad (5 min). Experiments were carried out in a small climatic chamber into which the hand was inserted. For convective cold exposure,T
sk was measured at seven points on the palmar surface of the fingers of the left hand, one on the palmar surface and one on the dorsal surface of the hand. The air temperature inside the mini-chamber was 0, 4, 10 and 16°C. With the contact cold exposure, the subjects touched at constant pressures an aluminium cube cooled to temperatures of –7, 0 and 7°C in the same mini-chamber. ContactT
sk was measured on the finger pad of the index finger of the left hand. TheT
sk of the proximal phalanx of the index finger (on both palm and back sides), and of the middle phalanx of the little finger was also measured. The variation ofT
sk between the proximal and the distal phalanx of the index finger was between 1.5 to 10°C during the convective cold exposure to an air temperature of 0°C. Considerable gradients persisted between the hand and fingers (from 2 to 17°C at 0°C air temperature) and between the phalanges of the finger (from 0.5 to 11.4°C at 0°C air temperature). The onset of cold induced vasodilatation (CIVD) on different fingers varied from about 5 to 15 min and it did not always appear in every finger. For contact cold exposure, whenT
sk on the contact skin cooled down to nearly 0°C, the temperature at the area close to the contact skin could still be 30°C. Some cases of CIVD were observed in the contact skin area, but not on other measuring points of the same finger. These results indicated that local thermal stimuli were the main determinents of CIVD. Representative hand skin temperature may require five or more measuring points. Our results strongly emphasised a need to consider the large spatial and individual variations in the prediction and modelling of extremity cooling. 相似文献