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[目的]探讨产前分娩预演对初产妇自然分娩成功率和产后并发症的影响.[方法]收集2016年9月至2018年10月在本院妇产科分娩的初产妇86例,按产前分娩教育方式分为观察组(n=42)和对照组(n=44).对照组孕妇产前接受常规产前健康教育课程培训,观察组在对照组的基础上进行分娩预演实践.比较两组自我效能感量表(GSES)、抑郁自评量表(SDS)和焦虑自评量表(SAS)评分及自然分娩成功率和产后并发症发生率等.[结果]与对照组相比,观察组分娩总产程和第一、二、三明显缩短;新生儿窒息率和产后SDS、SAS评分均明显降低;自然分娩成功率、GSES评分均明显提高,其差异均有统计学意义(P<0.05).观察组产后出血、感染、尿潴留、乳汁淤积发生率及总并发症发生率均低于对照组(P<0.05).[结论]采用常规产前健康教育培训结合产前分娩预演实践的产前管理方式,可有效提高初产妇自然分娩成功率,缩短产程,减少产后并发症的发生,值得临床推广应用.  相似文献   
3.
Balanced steady-state free precession (bSSFP) has become increasingly important in clinical applications. Its signal properties have been investigated over several years by many groups, and various critical factors for bSSFP signal intensity and stability, such as off-resonances, flow, and eddy currents, have been identified. It is generally accepted that bSSFP signal intensity is a function of relaxation times, excitation angles, and spin densities only. While this is true for simple phantoms, it appears that signals from tissues are significantly less intense than predicted by theory. This work demonstrates that the molecular origin of this apparent signal reduction is due to on-resonance magnetization transfer (MT). High flip angles in combination with very short repetition times (TRs), as commonly used for bSSFP, lead to a considerable saturation in the fraction of macromolecular (MM) pool protons. As a result, bSSFP signal is strongly attenuated by up to a factor of 2 in the human brain compared to the signal expected from theory.  相似文献   
4.
本文对5例典型尖锐湿疣标本及10例可疑人乳头瘤病毒感染标本进行透射电子显微镜观察。结果典型尖锐湿疣标本中仅1例于细胞核内见到人乳头瘤病毒,排列规则呈结晶状。其余14例标本的细胞内均见不同程度的由病毒感染所引起的非特异性病理变化。本文对人孔头瘤病毒及受感染细胞的超微结构进行了初步探讨。  相似文献   
5.
本研究应用层粘连蛋白(LN)抗体,对27例乳腺癌、5例乳腺良性病变进行了免疫组织化学研究。结果发现乳腺良性病变时,LN以均匀完整的线型阳性反应显示在乳腺导管及小叶基膜处。乳腺癌时,LN的染色表现为癌细胞胞浆内弥漫状阳性反应。27例乳腺癌中,癌细胞LN染色强度不同,伴有转移的乳腺癌LN染色多数较强,强度在++~的为7/12(58.3%);不伴有转移的病例,LN染色多数较浅或为阴性,强度在++~+++的病例为3/15(20%)。说明癌细胞内源性LN染色强弱与肿瘤转移密切相关,内源性LN的合成可能改变肿瘤细胞的浸润活性。  相似文献   
6.
用基因工程重组的丙肝抗原包被于硝酸纤维素膜,建立了检测丙肝IgG抗体的斑点免疫渗滤法。与ELISA试剂盒进行双盲式同步测定,二法检验结果差异无显著性。渗滤法简便快速,适用于各级医院,有很强的推广价值。  相似文献   
7.
Quantitative magnetization transfer imaging (qMTI) methods are able to estimate fundamental sample parameters, such as the relative size of the solid-like macromolecular proton pool and the spin exchange rate between this pool and the directly measured free water protons. One such method is selective inversion recovery (SIR), in which the free water protons are selectively inverted and the signal is fit to a biexponential function of the inversion time (TI). SIR uses only low-power pulses and requires no separate RF (B1) or static field (B0) field maps, and the analysis is largely independent of the macromolecular pool lineshape. These are all advantages over steady-state off-resonance saturation qMTI methods. However, up to now, SIR has been implemented only with repetition times TR>T1. This paper describes a modification of SIR with smaller TR values and a greater signal-to-noise ratio (SNR) efficiency.  相似文献   
8.
A reliable and reproducible immunofluorescence method is described for the detection of anti-cytoskeleton antibodies in human sera, based on the use of vinblastine-treated peripheral blood mononuclear cells as substrate. Three immunofluorescence patterns associated with antibodies to microfilaments, intermediate filaments and microtubules are readily identified.  相似文献   
9.
BACKGROUND: In bronchial asthma, subepithelial fibrosis in the conducting airways is associated with increased numbers of subepithelial fibroblasts. OBJECTIVE: This study examined the hypothesis that MMP-2 from airway epithelial cells induces the proliferation of subepithelial fibroblasts. METHODS: Using primary bronchial epithelial cells MMP-2, MT1-MMP and TIMP-2 mRNA expression were assessed by Northern blotting and RT-PCR. Primary bronchial epithelial cells transfected with constructs encoding pro-MMP-2 and MT1-MMP (MMP-14). RESULTS: Transfected cells showed enhanced expression of the appropriate mRNA species by RT-PCR and enhanced MMP-2 or MT1-MMP activity by zymography. Active MMP-2 levels in epithelial supernatants were increased most by cotransfection with pro-MMP-2 and MT1-MMP encoding constructs. By measuring tritiated thymidine incorporation, supernatants from transfected cells were found to enhance DNA synthesis of primary airway fibroblast cultures compared with controls. There was a strong correlation (r = 0.9, P < 0.01) between MMP-2 levels in epithelial cell conditioned media and fibroblast proliferation as indicated by DNA synthesis. The MMP inhibitor 1,10-phenanthroline attenuated the increased proliferation, while the addition of exogenous purified MMP-2 alone also increased fibroblast proliferation. CONCLUSIONS: Our results support a role for MMP-2 in mediating cross-talk between epithelial cells and myofibroblasts.  相似文献   
10.
The preparation steps usually necessary for obtaining ultrathin frozen sections of biological material (chemical prefixation, enclosing, cryoprotective treatment, freezing, sectioning, and post-staining the sections for transmission electron microscopy) are submitted to a critical analysis. The application of cryo-ultramicrotomy, in particularly for cytochemical purposes, is reviewed. Fundamental considerations of chemical prefixation and poststaining are supported by examples from yeast cytology. Furthermore, the efficiency of the cryo-ultramicrotomy (electron optical resolution of ultrastructural details) is demonstrated on yeast cells and protoplasts.  相似文献   
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