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21.
Telfer JF; Thomson AJ; Cameron IT; Greer IA; Norman JE 《Human reproduction (Oxford, England)》1997,12(10):2306-2312
Superoxide, an agent which attenuates the half-life of nitric oxide, is
metabolized and synthesized by superoxide dismutase (SOD) and xanthine
oxidase, respectively. Over the last few years much work has focused on the
role of nitric oxide in human parturition. The aim of this study was to
determine whether the onset of human parturition is associated with a
change in the expression of copper/zinc superoxide dismutase (Cu/Zn SOD),
manganese superoxide dismutase (Mn SOD) or xanthine oxidase within the
uterus. Samples of myometrium, placenta, decidua and fetal membranes were
obtained from women before and after the onset of labour at term.
Immunocytochemistry was used to localize Cu/Zn SOD, Mn SOD and xanthine
oxidase and measure SOD enzyme activity. Cu/Zn and Mn SOD-like
immunoreactivity was detected in syncytiotrophoblast cells, villous stromal
cells and endothelial cells of blood vessels in the placenta. In the
myometrium Cu/Zn and Mn SOD were localized to myocytes and endothelial
cells and to some vascular smooth muscle cells. In the fetal membranes we
observed staining for Cu/Zn SOD and Mn SOD in the amnion, chorion,
extravillous trophoblast and decidua. There was no difference in SOD enzyme
activity or staining intensity for SOD between different cell types before
and during labour. Xanthine oxidase immunoreactivity was identified in each
of the tissues examined and again there was no difference in immunostaining
in tissues obtained from women delivered before or after the onset of
labour. These results show that the pregnant uterus is capable of both
synthesizing and degrading superoxide and suggest that superoxide dismutase
and xanthine oxidase may play a role in the maintenance of uterine
quiescence during pregnancy, but not in the initiation of parturition.
相似文献
22.
IA Maartens T Wassenberg FJ Halbertsma HAM Marres P Andriessen 《Acta paediatrica (Oslo, Norway : 1992)》2009,98(11):1852-1854
A case report is presented of a rapidly growing congenital nasopharyngeal teratoma (epignathus) in a preterm infant, leading to severe upper airway obstruction. Prenatal diagnosis by ultrasonography did not reveal the condition because the tumour masses were initially small and there was no polyhydramnios. Epignathus is a rare cause of upper airway obstruction of the newborn that can grow rapidly in the neonatal period and should be treated surgically.
Conclusion: Epignathus is a rare cause of upper airway obstruction of the newborn that can grow rapidly in the neonatal period. 相似文献
Conclusion: Epignathus is a rare cause of upper airway obstruction of the newborn that can grow rapidly in the neonatal period. 相似文献
23.
Atlanto-axial rotatory fixation (AARF) is an uncommon condition which is often missed at presentation because of its rarity and the relative subtlety of plain film X-ray findings, but early detection and appropriate management are vital for a cure. We describe three cases in which the use of spiral computed tomography scanning with 3D and sagittal reconstructions greatly aided diagnosis and management. The 3D images gave a more graphic picture of the overall alignment of the upper cervical spine and the skull base, while the sagittal reconstructions demonstrated the presence or absence of compensatory atlanto-occipital subluxation. The literature is briefly reviewed. 相似文献
24.
JA Batch HR Davies BA Evans IA Hughes MN Patterson 《Archives of disease in childhood》1993,68(4):453-457
The partial androgen insensitivity syndrome occurs in 46,XY subjects with phenotypes ranging from perineoscrotal hypospadias with cryptorchidism and micropenis (mild undervirilisation) to clitoromegaly and partial labial fusion (marked undervirilisation). Within an affected family, wide variation in the degree of genital ambiguity between individuals can be seen. Two cousins of a previously reported subject who had severe genital ambiguity and partial androgen insensitivity were investigated. Neither of the cousins had genital abnormalities as marked as the index case, who also had qualitatively abnormal androgen binding and two mutations of the androgen receptor gene. Despite marked phenotypic differences between the index case and his cousins, similar androgen binding and the same androgen receptor mutations were shown in the cousins. Furthermore, one of the androgen receptor gene mutations has been shown in the mother and sister of one of the boys indicating that they are carriers. Thus phenotypic variation in families affected by partial androgen insensitivity is dependent on factors other than abnormalities of the androgen receptor gene alone. Although carrier status in partial androgen insensitivity can be determined, the severity of genital abnormalities in an affected offspring cannot be reliably predicted. 相似文献
25.
26.
Voutsadakis IA 《Medical oncology (Northwood, London, England)》2000,17(4):249-257
27.
本文观察了大鼠实验性急性胰腺炎时血浆和组织脂质过氧化物(LPO)的动态变化。发病后10h动物血浆LPO即见升高,而血浆淀粉酶水平则开始下降。发病10、20h心、肝、肾、肺组织LPO也有不同程度的升高。这证实了氧自由基在急性胰腺炎病理过程中起一定作用。与用血清淀粉酶水平判断急性胰腺炎的发生、发展这一传统方法相比,血浆LPO更能反映急性胰腺炎后期病变的程度及此时全身器官组织受损的情况。 相似文献
28.
双链断裂修复蛋白hKu70缺陷细胞株的建立及其生物学特性 总被引:1,自引:0,他引:1
目的 建立并鉴定DNA双链断裂(DSB)修复蛋白hKu70缺陷细胞株,并观察该缺陷细胞的某些生物学效应,用于AKu70基因功能及职业有害因素对DNA双链断裂修复影响的研究。方法 用构建的AKu70基因反义RNA绿色荧光蛋白真核表达载体(pEGFP—CI—K)转染人胚肺成纤维细胞(HLF),用蛋白兔疫印迹法鉴定转染细胞中AKu70基因的表达水平。同时观察转染细胞生长形态,绘制生长曲线,软琼脂培养法鉴定恶性程度。结果 pEGFP—CI—K载体在转染细胞内可较稳定表达,hKu70蛋白缺陷细胞株AKu70基因的蛋白表达水平下降了42%,转染后hKu70蛋白缺陷细胞生长形态、生长速度无明显变化,软琼脂培养未见细胞集落。结论 成功建立和鉴定了hKu70蛋白缺陷细胞株,该缺陷不足以单独引起可观察的某些生物学效应。 相似文献
29.
头孢克肟胶囊人体药动学研究及生物等效性评价 总被引:1,自引:0,他引:1
目的:研究头孢克肟胶囊在健康人体内的药动学及生物等效性。方法:以18名健康志愿者为试验对象,采用同体交叉试验方法,分别单剂量口服受试制剂或参比制剂各400mg,采用HPLC法测定血浆中药物浓度。结果:参比制剂和受试制剂的tmax分别为(3.39±0.50)和(3.39±0.50)h,cmax分别为(2.33±0.33)和(2.27±0.25)μg/mL,t1/2分别为(3.92±0.85)和(4.41±0.68)h,AUC0~16分别为(14.61±2.67)和(14.82±2.02)μg·h·mL^-1,AUC0~∞分别为(16.00±3.13)和(16.81±2.62)μg·h·mL^-1。结论:受试制剂与参比制剂生物等效,受试制剂的相对生物利用度为(98.69±13.13)%。 相似文献
30.
The immediate-spin (IS) crossmatch is used to detect ABO incompatibility between donor red cells (RBCs) and the serum of the intended recipient. However, this test may be positive in the absence of ABO incompatibility (false positive) or it may be negative when ABO incompatibility exists (false negative). During a 25-month study, the rates of both false-positive and false-negative IS crossmatch results were evaluated, and the sensitivity and specificity of the IS crossmatch were determined. During the study period, 53,656 IS crossmatches were performed for patients without significant RBC antibodies. Fifty-five patients had positive IS crossmatches, and no false-negative reactions were found. In tests of 55 patients with positive IS crossmatches, 77 false-positive and 5 true-positive reactions were noted. The causes of the false-positive reactions were rouleaux (36 patients), cold-reactive antibodies (8 patients), a combination of rouleaux and cold-reactive antibodies (2 patients), fibrin clot (1 patient), and undetermined (3 patients). The sensitivity and specificity of the IS crossmatch were 100 and 99.86 percent, respectively. Laboratory personnel should be aware that the IS crossmatch may have false-positive or false-negative results, and they should develop written protocols to distinguish quickly between true-positive and false-positive reactions. 相似文献