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81.
增生性玻璃体视网膜病变基质金属蛋白酶的定量研究 总被引:5,自引:0,他引:5
目的:研究增生性玻璃体视网膜病变(proliferative vitreoretinopathy,PVR)玻璃体中基质金属蛋白酶(matrix metalloproteinases,MMPs)的表达,探讨MMPs在PVR病理过程中的作用。方法:PVR患者采用标准三切口巩膜扁平部玻璃体切割术(pars plana vitrectomy,PPV),取未稀释的玻璃体21只眼,PPV术后复发的玻璃体腔液20只眼,意外死亡的正常人玻璃体10只眼,采用明胶酶谱分析法定量分析MMP-2和MMP-9活性水平。结果:PVR玻璃体有MMP-2活性水平增高,与正常玻璃体比较差异有显著性意义(P<0.05)。21眼PVR玻璃体中13只眼有MMP-9活性水平增高,平均(171.52±13.17)扫描单位。20眼PPV术后PVR复发的玻璃体腔液19只眼有MMP-9活性水平增高,平均(156.01±37.21)扫描单位。正常人玻璃体无MMP-9的表达。结论:PVR玻璃体有MMP-2和MMP-9活性水平增高,MMP-9活性水平增高可能与术后PVR复发有关。眼科学报2003;19:130-132。 相似文献
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Reinaldo Figueroa MD Edilberto Martinez MD Raisa P. Fayngersh MD Hong Jiang MD Hatim A. Omar MD Nergesh Tejani MD Michael S. Wolin PhD 《American journal of obstetrics and gynecology》1995,173(6):1800-1806
OBJECTIVE: Our objective was to determine whether the observed relaxation to lactate and other agents in placental vessels of normal pregnancies is altered in severe preeclampsia.STUDY DESIGN: Isolated placental arteries and veins from women with severe preeclampsia and uncomplicated term pregnancies were precontracted with prostaglandin F2α under 5% oxygen and 5% carbon dioxide with the balance nitrogen (Po2 35 to 38 torr) and then exposed to lactate (1 to 10 mmol/L, pH 7.4, n = 8 to 15), arachidonic acid (0.01 to 10 μmol/L, n = 6 to 13), nitroglycerin (1 nmol to 1 μmol/L, n = 4 to 12), or forskolin (0.01 to 10 μmol/L, n = 6 to 9). The response to lactate was also examined in placental vessels from appropriate-for-gestational-age preterm deliveries (n = 8) for comparison with a similar group with severe preeclampsia (n = 8). The t test and analysis of variance statistics were used.RESULTS: Relaxation to lactate was markedly inhibited in both placental arteries and veins of women with severe preeclampsia compared with vessels from uncomplicated term or preterm pregnancies. Responses to the other relaxing agents were not altered in the severely preeclampsia vessels.CONCLUSIONS: In severe preeclampsia absence of lactate-induced dilatation of placental vessels may contribute to the fetal complications associated with impaired blood flow and vasospasm. 相似文献
84.
Toshiaki Nakashima Fuminori Goda Jinge Jiang Toshihide Shima Harold M. Swartz 《Magnetic resonance in medicine》1995,34(6):888-892
The partial pressure of oxygen (pO2) of the liver in vivo in unanesthetized mice was determined using electron paramagnetic resonance (EPR) oximetry with India ink. The EPR spectra were obtained using a low-frequency (1.2 GHz) EPR spectrometer with a loop gap cavity resonator. The line width of the India ink used in this experiment was reversibly broadened by oxygen and was particularly sensitive to pO2 below 30 torr. After the administration of India ink into the tail vein, the India ink particles were taken up mainly by Kupffer cells in the liver and in part by phagocytes in the spleen. The pO2 measured in the normal liver was about 14 torr and was constant for the 2-week experimental period. The pO2 decreased when measured at 1, 2, and 6 days after treatment with a hepatotoxin (carbon tetrachloride (CCI4)); within 2 weeks, it returned almost to the initial level. Measurements by EPR at sacrifice of controls and CCI4-treated mice indicated that more than 90% of the India ink went to the liver; the spleen contained 4.7% of total amount in control mice and 8.8% in CCI4-treated mice when measured 2 weeks after the treatment. These data indicate the usefulness of India ink for measuring the pO2 of the liver in vivo and that the pO2 in the Kupffer cells is decreased when the liver is damaged by CCI4. 相似文献
85.
胎儿腹壁异常的超声诊断 总被引:5,自引:0,他引:5
本文总结了胎儿腹壁异常12例,其中脐疝4例,腹壁缺损4例、膈疝3例、胸腹壁缺损1例。分析了超声图像特点及漏诊、误诊原因,并提出鉴别诊断要点及最早诊断时间。对分娩方式及时间选择有重要意义。 相似文献
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87.
Xiaomei Zhou Jianren Gu Yuanqing Cheng Huiqiu Jiang Lianfang Qian Guowei Xu Shafritz David 《中国癌症研究》1992,4(3):10-14
This is first report about the simultaneous over-expression of both Insulin-like growth factor (IGF-II) and its receptor (IGF-II
R) at mRNA level in human primary hepatic Cancer (PHC). In 10 PHC samples from China, IGF-II and IGF-II R were both over-expressed,
whereas only a background signal was detected in normal liver. In 5 pairs of PHC and its non-tumorous adjacent liver tissues
from South Africa, IGF-II and IGF-II R were also over-expressed in PHC. mRNA expression of IGF-II in all 5 cases and IGF-II
R in 4 of 5 cases were higher in cancer than non-tumorous adjacent liver tissues. These results strongly implicate that an
autocrine and/or paracrine mechanism might be involved in formation and progression of PHC. 相似文献
88.
Twenty-eight breasts of 15 patients with macromastia underwent reduction mammaplasty from 1982 to 1989. We followed up these patients postoperatively for 6 months to 7 years. The follow-up time for 8 patients was over 1 year, and 4 patients over 5 years. And 3 patients labored and lactated. These 15 patients were satisfied with this operative results. The operative technology was based on Pitange's method. This method improved the site of the nipple, transposition of nipple-areola complex, and design of dermal pedicle, so that it had better effects in the breast shape, breast fixation and incision scar concealed. We suggest that the purpose of macromastia treated in reducing volume, improving breast shape, preserving lactating function. This paper also discusses the methods for nipple site, nipple-areola complex transposition, breast resection and mastopexy. 相似文献
89.
我们在慢性前列腺炎的治疗中,通过学习叶天士《临证指南医案·淋浊》一篇,受益良深。古人虽受解剖学知识的限制,很难了解病变的具体部位,但从叶氏的医案中可以看出,他对“精浊”的认识与现代慢性前列腺炎基本吻合。叶氏认为,尽管淋证(泌尿系感染)与 相似文献
90.