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排序方式: 共有536条查询结果,搜索用时 31 毫秒
111.
Akila Subramaniam Sue S. Cliver Stephanie Smeltzer Alan T. Tita Luisa L. Wetta 《The journal of maternal-fetal & neonatal medicine》2016,29(12):1895-1899
Objective: Our objective was to compare maternal and neonatal outcomes in patients with preterm premature rupture of membranes (PPROM) delivered prior to 34°/7 weeks upon confirmation of fetal lung maturity (FLM) to those managed expectantly until 34°/7 weeks.Methods: We performed a retrospective cohort study of non-anomalous singleton gestations with PPROM occurring after 24 weeks delivered between 32°/7 and 34°/7 weeks from 2004 to 2012. Patients delivered upon documented FLM (+FLM) – defined as the presence of phosphatidylglycerol (PG) at 32°/7–336/7 weeks if amniotic fluid was obtainable vaginally – were compared with patients delivered without documented FLM between 32°/7 and 34°/7 weeks (expectant). Primary outcomes included maternal infection (clinically diagnosed endometritis or chorioamnionitis), placental abruption and a composite of neonatal morbidities (including but not limited to mechanical ventilation, intraventricular hemorrhage, necrotizing enterocolitis, sepsis and respiratory distress syndrome). Statistical analysis was performed using Student’s t-test for continuous variables and Chi-square or Fisher’s exact test for categorical data. Covariates were analyzed via multivariate logistic regression and adjusted odds ratios were calculated.Results: Of 237 PPROMs delivered at 32°/7–34°/7 weeks, 74 were intentionally delivered for +FLM and 163 were expectantly managed. No cord prolapse or stillbirth was observed. Maternal infection (chorioamnionitis or endometritis) was lower in the +FLM group (aOR 0.33 95% CI 0.12–0.88). Overall, there was no difference in composite neonatal morbidity did not differ between the two groups (aOR 1.36 95% CI 0.53–3.54).Conclusions: In patients with PPROM, delivery after confirmation of FLM at 32°/7–336/7 weeks compared with expectant management until 34°/7 weeks may prevent maternal infection without increasing neonatal morbidity. 相似文献
112.
HPLC柱切换法血浆直接进样测定糖肾平 总被引:9,自引:0,他引:9
采用HPLC柱切换技术,以Merck Lichroprep RP2(25~40μm)为预处理柱填料,以水为预处理流动相,以0.2mol/L乙酸-乙酸铵为净化清洗液,血浆直接进样,在线富集净化样品。血浆样品以0.2ml/min慢速转移通过预处理柱,净化回收率达80%。以ShimpackCLC-ODS为分析柱(15cm×6mm,ID),甲醇-异丙醇-0.2mol/L 乙酸铵(61:5:34)为分析流动相,310nm波长检测,外标法定量测定人体血浆中糖肾平的浓度。血浆样品仅需稀释后即可进样,净化富集样品操作简便,预处理柱可长期反复进样使用。血浆中最低检测浓度为30ng/ml,日内变异系数为2.0%~5.4%,日间变异系数为2.4%~2.7%,在浓度为60~2020ng/ml血浆范围内呈线性关系。 相似文献
113.
Carcinogenic polycyclic aromatic hydrocarbons increase intracellular Ca2+ and cell proliferation in primary human mammary epithelial cells 总被引:1,自引:1,他引:1
Previous studies have shown that polycyclic aromatic hydrocarbons (PAHs)
mobilize intracellular Ca2+ in human T cells by inositol
trisphosphate-dependent mechanisms resulting from activation of
phospholipase C-gamma by SRC-related protein tyrosine kinases, thereby
mimicking antigen-receptor activation. Ca2+ appears to play an important
second messenger role in growth factor control of cell proliferation in
human mammary epithelial cells (HMEC), such as the epidermal growth factor
receptor pathway. The purpose of the present studies was to determine if
PAHs are able to increase intracellular Ca2+ in primary cultures of HMEC
and increase cell proliferation. Two carcinogenic and two non-carcinogenic
PAHs were tested for their ability to increase intracellular Ca2+ in HMEC.
The carcinogenic PAHs dimethylbenz[a]anthracene (DMBA) and benzo[a] pyrene
(BaP) were able to cause Ca2+ elevation in HMEC at early time points (2 h)
and caused sustained alterations in Ca2+ homeostasis (18 h). DMBA showed
maximal effects at early time points (2 h), while BaP showed maximal
effects on sustained Ca2+ (18 h). 2,3,7,8-Tetrachlorodibenzo-p-dioxin
(TCDD), a potent dioxin and tumor promoter, produced maximal Ca2+ elevation
at 2 h, with a return to near baseline levels by 6 h. The non-carcinogenic
PAHs benzo[e]pyrene and anthracene did not significantly alter
intracellular Ca2+ at any time point. alpha-Naphthoflavone significantly
reduced the Ca2+ response induced by BaP treatment, but not by DMBA or
TCDD, suggesting that P450 1A or 1B metabolism of BaP may be important in
the sustained Ca2+ elevating response. In evaluating the effects of BaP on
HMEC proliferation, BaP was found to increase the number of cells recovered
after 4 days in culture in the absence or presence of various
concentrations of epidermal growth factor. These studies provide initial
evidence that Ca2+ signaling may be associated with mitogenesis in HMEC,
which may play a role in tumor promotion and progression produced by PAHs.
相似文献
114.
目的:采用交流示波极谱滴定法测定了盐酸环丙沙星及其制剂的含量。方法:在pH5.0-5.5的醋酸-醋酸钠缓冲液溶液中,环丙沙星与四苯硼钠定量反应形成1:1沉淀。过量的四苯硼钠用醋酸亚铊标准溶液回滴至示波极谱图上四苯硼钠切口消失。结果:该法平均回收率为99.18%,RSD为0.49%。结论:本法简便,快速,结果准确,可靠。 相似文献
115.
116.
117.
合欢皮中三萜皂甙元的研究 总被引:3,自引:0,他引:3
合欢皮中三萜皂甙元的研究陈四平张如意(北京医科大学植化教研室,北京100083)中药合欢皮(Albizziaecortex)为合欢(AlbizziaejulibrisinDurazz)树皮。具解郁安神,活血消肿功能。用于心神不安,忧郁失眠,肺痈疮肿... 相似文献
118.
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120.
The reliability and construct validity of the RAQoL: a rheumatoid arthritis-specific quality of life instrument 总被引:6,自引:4,他引:6
de Jong Z; van der Heijde D; McKenna SP; Whalley D 《Rheumatology (Oxford, England)》1997,36(8):878-883
The present study was designed to test the psychometric properties of the
RAQoL, a rheumatoid arthritis (RA)-specific quality of life (QoL)
instrument. All stages of the development were conducted simultaneously in
The Netherlands and the UK. The content of the draft measure was derived
from qualitative interviews with RA patients in both countries. The final
version of the RAQoL has 30 items with a 'yes'/'no' response format and
takes approximately 6 min to complete. Both language versions have high
internal consistency and test-retest reliability (> 0.9), and good
sensitivity to discriminate between groups with various disease activity
and severity. Given the excellent psychometric properties of the new
instrument, it will prove to be a valuable tool for assessing quality of
life in clinical trials and for monitoring patients in routine clinical
practice.
相似文献