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11.
摘要 目的:探讨磁共振成像在剖宫产术后瘢痕妊娠(cesarean scar pregnancy,CSP)诊疗路径中的应用价值。方法:回顾性分析24例经手术和(或)病理证实为瘢痕妊娠的孕妇临床和影像检查资料,记录MRI上妊娠囊位置、大小、T1、T2信号强度、妊娠囊类型、妊娠囊与子宫前壁下段肌层及膀胱的关系,分析MR特征对临床诊疗路径的应用价值。结果:24例妊娠囊均位于子宫下段,为圆形或卵圆形,11例妊娠囊为单纯囊性,12例妊娠囊为混杂包块型,1例因清宫术后行MR,未见明确妊娠囊,仅见子宫下段混杂信号。10例妊娠囊附着处子宫肌厚度不可测量,余14例妊娠囊附着处子宫肌厚度约0.9~5.0 mm,平均2.5±1.1 mm。据此,CSP分型为I型5例,II型7例,III型12例。结论:MRI能较好的评估CSP, 在CSP诊疗路径中的应用价值较大。 相似文献
12.
摘要 目的:探究气压治疗仪联合那屈肝素预防剖宫产术后下肢静脉栓塞(DVT)的临床效果。方法:选取2021年1月~2022年8月长沙市妇幼保健院收治的172例剖宫产孕妇,以随机数字表法按1:1比例分为联合组、常规组,各86例。常规组采用那屈肝素预治疗,联合组采用气压治疗仪联合那屈肝素治疗。比较两组DVT发生率;术前、术后5 d凝血功能指标[凝血酶时间(TT)、纤维蛋白原(FIB)、活化部分凝血活酶时间(APTT)、凝血酶原时间(PT)]、血液流变学指标[全血高切黏度、血浆黏度、全血低切黏度];术前、术后1 d、5 d大小腿腿围;术前、术后1 d、3 d、5 d疼痛视觉模拟量表(VAS)评分。结果:联合组DVT发生率3.49%较常规组11.63%低(P<0.05);术后5 d联合组PT、APTT、TT较常规组高,FIB较常规组低(P<0.05);术后5 d联合组全血高切黏度、血浆黏度、全血低切黏度较常规组低(P<0.05);术后1 d、5 d联合组大小腿腿围较常规组低(P<0.05);术后1 d、3 d、5 d联合组VAS评分较常规组低(P<0.05)。结论:气压治疗仪联合那屈肝素能有效改善剖宫产产妇术后凝血功能及血液流变学,缓解下肢肿胀,减轻术后疼痛,减少DVT的发生。 相似文献
13.
摘要 目的:探讨急诊危重孕产妇5分钟紧急剖宫产的临床效果,并分析新生儿不良结局的危险因素。方法:回顾性分析2018年1月~2022年6月在河北省儿童医院妇产科收治的急诊危重孕产妇139例的临床资料。根据急诊剖宫产流程分为对照组(n=68,常规紧急剖宫产流程下进行手术)及观察组(n=71,5分钟紧急剖宫产)。观察两组孕产妇的手术情况、手术反应时间、孕产妇并发症、新生儿不良结局发生率。采用多因素Logistic回归模型分析新生儿不良结局的危险因素。结果:两组住院时间、术中出血量、术中输血情况组间对比,未见统计学差异(P>0.05)。与对照组相比,观察组进手术室至手术开始时间、决定手术至胎儿娩出的时间间隔(DDI)、决定手术至进手术室时间、手术开始至胎儿娩出时间均更短,新生儿不良结局发生率、并发症发生率更低(P<0.05)。根据新生儿不良结局将孕产妇分为不良组(n=38)、良好组(n=101)。单因素分析结果显示:新生儿不良结局与受教育程度、新生儿体重、孕周、剖宫产类型、DDI、妊娠合并症、采用辅助生殖技术有关(P<0.05)。多因素Logistic回归分析结果显示,受教育程度为小学及其以下、新生儿体重偏低、剖宫产类型为I类剖宫产、孕周偏短、DDI偏长均是新生儿不良结局的危险因素(P<0.05)。结论:急诊危重孕产妇5分钟紧急剖宫产可缩短各项手术反应时间,降低孕产妇并发症和新生儿不良结局发生率。此外,新生儿不良结局的发生与受教育程度、新生儿体重、剖宫产类型、孕周、DDI等因素有关。 相似文献
14.
In the marine unicellular chlorophyte, Dunaliella tertiolecta Butcher, the spectrally averaged m vivo absorption cross section, normalized to chlorophyll a (so-called a* values), vary two-fold in response to changes in growth irradiance. We used a kinetic approach to examine the specific factors which account for these changes in optical properties as cells photoadapt. Using Triton X-100 to solubilize membranes, we were able to differentiate between “package” effects and pigmentation effects. Our analyses suggest that 43–49% of the variability in a* is due to changes in pigmentation, whereas 51–57% is due to the “package” effect. Further analyses revealed that changes in cell sue did not significantly affect packaging, while thylakoid stacking and the transparency of thylakoid membranes were important factors. Our results suggest that thylakoid membrane protein/lipid ratios change during photoadaptation, and these changes influence the effective rate of light harvesting per unit chlorophyll a. 相似文献
15.
A new Type II restriction endonuclease XcyI, purified from Xanthomonas cyanopsidis 13D5, is an isoschizomer of SmaI and XmaI that cleaves at the nucleotide sequence 5'-C decreases CCGGG-3' of double-stranded DNA. The single restriction activity present in this strain permits rapid purification of 8000 units of cleavage activity from 10 g of freshly harvested cells. The resulting XcyI preparation is free of contaminating nuclease activities that interfere with in vitro manipulation of DNA. 相似文献
16.
Use of lambda phasmids for deletion mapping of non-selectable markers cloned in plasmids 总被引:5,自引:0,他引:5
A nonselectable gene carried on a poorly selectable recombinant plasmid has been physically mapped by deletion analysis. Our method involved cloning the plasmid into a coliphage lambda vector and treating the recombinant phage with a chelator. Virtually all particles surviving this treatment carried large deletions within the plasmid insert. Further deletion analysis was done by inserting a selectable lambda sequence into one such deletion derivative and repeating the chelator selection. Chelator selection was also used to isolate deletions constructed in vitro. The deleted phage are readily characterized by restriction mapping, and the gene in question scored after infection of a mutant host strain. These techniques have enabled us to physically assign the cyclopropane fatty acid synthase gene of Escherichia coli to 0.8 kb of a 16-kb segment after characterizing only a small number of isolates. This approach should be generally useful in the mapping of plasmids for which no convenient method exists for selecting or scoring the gene in question. 相似文献
17.
18.
Isolation and characterization of pock-forming plasmids for Streptomyces griseus from soil actinomycetes 总被引:3,自引:0,他引:3
Thirty independent actinomycetes strains carrying plasmids were isolated from soil. These plasmids were purified as cccDNA by CsCl-EtBr equilibrium density-gradient centrifugation. Plasmids that induce "pocks", namely formation of circular zones of sporulation-inhibition, were selected by protoplast transformation of streptomycin-producing strain, Streptomyces griseus ATCC10137. Six pock-forming plasmids, pOA7, pOA11, pOA15, pOA23, pOA29 and pOA30, were obtained, and their cleavage maps, transformation frequencies, and copy numbers, as well as their stability, are described. 相似文献
19.
Mathias Uhlén Björn Nilsson Bengt Guss Martin Lindberg Sten Gatenbeck Lennart Philipson 《Gene》1983,23(3):369-378
Two plasmid vectors, containing the gene coding for staphylococcal protein A and adapted for gene fusion, have been constructed. These vectors will allow fusion of any gene to the protein A gene, thus giving hybrid proteins which can be purified, in a one-step procedure, by IgG affinity chromatography. As an example of the practical use of such vectors, the protein A gene has been fused to the lacZ gene of Escherichia coli. E. coli strains containing such plasmids produce hybrid proteins with both IgG binding and β-galactosidase activities. The hybrid protein(s) can be immobilized on IgG-Sepharose by its protein A moiety with high efficiency without losing its enzymatic activity and they can be eluted from the column by competitive elution with pure protein A. The fused protein(s) also binds to IgG-coated microtiter wells which means that the in vivo product can be used as an enzyme conjugate in ELISA tests. 相似文献
20.
Summary The threedimensional ultrastructure of presynaptic dense bars was examined by serial section electron microscopy in the excitatory neuromuscular synapses of the accessory flexor muscle in the limbs of larval, juvenile, and adult lobsters. The cross-sectional profile of the dense bar resembles an asymmetric hourglass, the part contacting the presynaptic membrane being larger than that projecting into the terminal. The bar has a height of 55–65 nm and varies in length from 75–600 nm. In its dimensions it resembles the dense projections in the synapses of the CNS of insects and vertebrates. The usual location of these dense bars is at well defined synapses, though a few are found at extrasynaptic sites either in the axon or terminal. In the latter case the bars are close to synapse-bearing regions, particularly in the larval terminals, suggesting that the extrasynaptic bars denote early events in synapse formation. In all cases the bars are intimately associated with electron lucent, synaptic vesicles located on either side, in the indentation of its hourglass-shaped cross sectional profile. The vesicles occur along the length of the bar and contact the presynaptic membrane. Consequently the dense bar may serve to align the vesicles at the presynaptic membrane prior to exocytosis. A similar role has been suggested for the presynaptic dense bodies at the neuromuscular junction of the frog, where synaptic vesicles form a row on either side of this structure.Supported by Muscular Dystrophy Association of Canada and NSERCC. Generous use of laboratory facilities at Woods Hole was provided by the late Fred Lang 相似文献