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201.
BACKGROUND: Impaired implantation in assisted reproduction cycles with high serum estradiol (E(2)) concentrations may be related to suboptimal endometrial perfusion. Endometrial and subendometrial blood flow were compared between excessive responders (serum E(2) on the day of HCG >20 000 pmol/l) and moderate responders (E(2) < or =20 000 pmol/l). METHODS: Three-dimensional (3D) ultrasound examination with power Doppler was performed 2, 4 and 7 days after HCG in 32 patients who did not have embryo transfer in order to measure endometrial thickness, pulsatility index (PI)/resistance index (RI) of uterine vessels, and endometrial volume, vascularization index (VI)/flow index (FI)/vascularization flow index (VFI) of endometrial and subendometrial regions. RESULTS: Excessive responders tended to have lower endometrial and subendometrial VI/VFI on HCG +2 and more absent endometrial/subendometrial blood flow. They had significantly higher endometrial FI and subendometrial VFI than moderate responders on HCG +7. Only in the excessive responder group, uterine PI/RI declined significantly from HCG +2 to HCG +7 and endometrial VI/VFI increased significantly from HCG +4 to HCG +7. CONCLUSION: Changes in uterine Doppler flow indices, and endometrial and subendometrial 3D power Doppler flow indices during the early luteal phase were significantly different between moderate and excessive responders. 相似文献
202.
大鼠小脑皮质内突触素P38免疫反应产物的分布及年龄变化 总被引:6,自引:0,他引:6
用免疫组织化学方法结合图像分析研究突触素P38免疫反应产物在Wistar大鼠小脑皮质的分布及年龄变化,结果显示:小脑皮质内的突触素P38免疫反应产物呈板层分布,各层之间的 产物密度差异很大;在三个年龄组,小脑V,Ⅶ叶分子层突触素P38免疫反应产物校正光密度值以青年组最大,成年组次之,老年组最小,各组间差异显著。 相似文献
203.
硫代乙酰胺所致急性肝衰时内毒素血症与肝内胆汁淤积关系的研究 总被引:1,自引:0,他引:1
本实验采用硫代乙酰胺(thioacetamide,TAA)灌胃复制大鼠急性肝功能衰竭的动物模型。检测血中内毒素、转氨酶、脂蛋白-x等含量以及胆汁流量。结果表明,大鼠发生了肝内胆汁淤积与内毒素血症(ETM),并且两者呈正相关(P<0.05)。同时肝细胞膜上Na -K -ATP酶的活力明显降低,与ETM含量呈负相关(P<0.05)。结果提示:ETM与肝内胆汁淤积的发生有密切关系. 相似文献
204.
氧分压在体监测仪的研制 总被引:2,自引:0,他引:2
作者报道一种稳定性较高的氧分压在体监测,为医学研究、临床诊断提供一种新的可靠的测试方法及设备,具有较大的应用价值。 相似文献
205.
目的:检测充血性心力衰竭(CHF)患者血清肿瘤坏死因子-α(TNF-α)、一氧化氮(NO)的变化,以及血管紧张素Ⅱ(AngⅡ)、缬沙坦对培养的正常人和CHF患者单核细胞(PBMC)分泌TNF-α、NO的影响,探讨CHF时肾素血管紧张素系统与细胞因子的联系以及缬沙坦治疗CHF的细胞因子机制。方法: 取16例Ⅲ-Ⅳ级的CHF患者静脉血,检测血清TNF-α、NO含量;分离PBMC,置24孔培养板中,分别加入AngⅡ,使其终浓度分别为0、0.01、0.1、1 μmol/L,另外一孔加入0.1 μmol/L的AngⅡ和0.1 μmol/L的缬沙坦,经24 h孵化后,检测培养上清中TNF-α、NO。结果: CHF患者血清TNF-α、NO水平显着高于对照组(P<0.01),心功能Ⅳ级组显著高于心功能Ⅲ级(P<0.01)。不同病因CHF患者之间TNF-α、NO含量无显著差异(P>0.05)。 AngⅡ对正常人和CHF患者PBMC分泌TNF-α、NO均有促进作用,缬沙坦抑制AngⅡ诱导的PBMC分泌TNF-α、NO。 结论: AngⅡ促进PBMC产生TNF-α、NO,提示肾素-血管紧张素系统与TNF-α、NO存在一定的联系,缬沙坦可能通过抑制TNF-α、NO的产生在CHF的治疗中发挥作用。 相似文献
206.
Evan D. Nair-Gill Chengyi J. Shu Caius G. Radu Owen N. Witte 《Immunological reviews》2008,221(1):214-228
Summary: Non-invasive monitoring of adaptive immunity in infection, cancer, and autoimmunity remains a major challenge. Current techniques to monitor lymphocytes involve numeric and functional determinations of immune cells isolated from the peripheral blood (most often) and tissue (rarely). Invasive measurements are prone to sampling errors and are poorly reflective of the dynamic changes in the location, number, and movement of lymphoid cells. These limitations indicate the need for non-invasive whole-body imaging methodologies that allow longitudinal, quantitative, and functional analyses of the immune system in vivo . Positron emission tomography (PET), a clinically based whole-body imaging modality, has the potential to revolutionize diagnostics and therapeutic monitoring in both clinical and pre-clinical settings. This review discusses studies using PET to image adaptive immune responses in small animal models. We address the challenges inherent in assessing whole-body immunity with PET and recent developments that can improve its performance. Finally, we discuss work to translate PET immune imaging into clinical practice. 相似文献
207.
An animal model of SARS produced by infection of Macaca mulatta with SARS coronavirus 总被引:16,自引:0,他引:16
Qin C Wang J Wei Q She M Marasco WA Jiang H Tu X Zhu H Ren L Gao H Guo L Huang L Yang R Cong Z Guo L Wang Y Liu Y Sun Y Duan S Qu J Chen L Tong W Ruan L Liu P Zhang H Zhang J Zhang H Liu D Liu Q Hong T He W 《The Journal of pathology》2005,206(3):251-259
A new SARS animal model was established by inoculating SARS coronavirus (SARS-CoV) into rhesus macaques (Macaca mulatta) through the nasal cavity. Pathological pulmonary changes were successively detected on days 5-60 after virus inoculation. All eight animals showed a transient fever 2-3 days after inoculation. Immunological, molecular biological, and pathological studies support the establishment of this SARS animal model. Firstly, SARS-CoV-specific IgGs were detected in the sera of macaques from 11 to 60 days after inoculation. Secondly, SARS-CoV RNA could be detected in pharyngeal swab samples using nested RT-PCR in all infected animals from 5 days after virus inoculation. Finally, histopathological changes of interstitial pneumonia were found in the lungs during the 60 days after viral inoculation: these changes were less marked at later time points, indicating that an active healing process together with resolution of an acute inflammatory response was taking place in these animals. This animal model should provide insight into the mechanisms of SARS-CoV-related pulmonary disease and greatly facilitate the development of vaccines and therapeutics against SARS. 相似文献
208.
ObjectiveTo
understand the mechanism of liver cirrhosis after the infection of hepatitis B virus.MethodsMouse
fibroblast NIH3T3 cells were transfected with 3.2 kb HBV DND by exposure of the cells to
calcium phosphate.The change of the levels of mRNA for tissue inhibitor of
metalloproteinase 1and 2(TIMP1,2) was detected in mouse fibroblast NIH3T3 cells and the cells of transfection
with HBV Genome by in situ hybridization.ResultsThe levels of mRNA for
TIMP1 and TIMP2 were increased significantly.ConclusionHBV infection can
induce the expression of the mRNA for TIMP1 and TIMP2. 相似文献
209.
我们对采用PCR和聚丙烯酰胺凝胶电泳鉴别出的37例DNA完全来自父方的遗传学完全性葡萄胎(g-CHM)进行基因组中CTTtriplex系统各基因座位(CSF1PO、TPOX和TH01)等位基因分布的分析,并初步研究了这些等位基因分布与临床预后的关系。结果显示,在37例g-CHM中,CSF1PO座位中3个等位基因(11,12和14)和TPOX座位中的1个等位基因(11)的出现率与它们在北京地区人群中的基因频率差异显著;g-CHM中CSF1PO、TPOX和TH01基因座位杂合度显著低于北京地区人群的杂合度(P值均远小于0.01);在23例良性g-CHM和10例侵袭性g-CHM中:CSF1PO座位的等位基因10、11在良性中的出现率高于在侵袭性g-CHM中(P=0.026148),等位基因12在良性中的出现率低于在侵袭性g-CHM中(P=0.023879);TPOX座位的等位基因8在良性中的出现率高于在侵袭性g-CHM中(P=0.004322),而等位基因11在良性中的出现率低于其在侵袭性g-CHM中(P=0.008671)。上述结果提示,葡萄胎基因组中存在某些等位基因分布与在人群中的分布不同,而且葡萄胎是否具有侵袭性也和某些等位基因的出现率过高或过低有相关性,这些与侵袭性有关的等位基因可能成为预测葡萄胎是否具有侵袭性的标志物。 相似文献
210.
Liu Y Shu XZ Gray SD Prestwich GD 《Journal of biomedical materials research. Part A》2004,68(1):142-149
The modification of hyaluronan (HA) and gelatin using dithiobis(propanoic dihydrazide) (DTP) has provided two thiolated macromolecular components of the extracellular matrix (ECM), specifically HA-DTPH and gelatin-DTPH. Blends of these thiolated ECM components were crosslinked in air to form hydrogels that were interpenetrating disulfide-crosslinked networks. Lyophilization of the hydrogels afforded sponge-like macroporous scaffolds suitable for cell attachment and proliferation. Increasing percentages of gelatin-DTPH (0, 25, 50, and 75%) were blended with HA-DTPH, and the resulting sponges were evaluated in vitro and in vivo as scaffolds for tissue engineering by seeding with human tracheal scar (HTS) fibroblasts. While cells failed to attach and grow in HA-only sponges, the gelatin-modified HA sponges promoted cell adhesion, proliferation, and spreading in vitro. Optimal attachment and growth was observed with 50% gelatin-HA sponges. Cell attachment to the gelatin-HA sponge could be blocked by preincubation of cells with a soluble fibronectin peptide Gly-Arg-Gly-Asp (GRGD). Finally, HTS fibroblast-seeded gelatin-HA sponges were implanted into the flanks of nude mice and evaluated at 2 and 8 weeks postimplantation. The sponges were fully biocompatible and new fibrous tissue formed, gradually replacing the sponge-like scaffold. The gelatin-HA sponges act as synthetic, macroporous, covalent mimics of the ECM and constitute novel scaffolds for cell growth and tissue augmentation. 相似文献