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81.
目的探讨子宫下段暂时性环扎在中央型前置胎盘术中出血处理的应用效果及安全性。方法回顾性分析2011年6月至2015年6月绵阳市妇幼保健院收治的中央型前置胎盘患者90例的临床资料,根据止血方式将其分为观察组(54例)与对照组(36例),对照组产妇采取常规止血治疗,观察组产妇在剥离胎盘前及子宫局部处理或全切除前,迅速使用一次性硅胶尿管环扎子宫下段阻断子宫体血液供应,在子宫体血运阻断后进行常规止血操作,术后放开环扎尿管恢复子宫血供(排除子宫已切除患者),比较两组产妇治疗效果及临床结局。结果两组产妇干预前出血量比较差异无统计学意义(P0.05);观察组产妇卡前列素氨丁三醇用量、术中总出血量、总输血量、子宫切除率明显低于对照组,差异有统计学意义(P0.05);两组患者止血成功率均为100%;两组患者子宫坏死、切口感染、宫腔积血等并发症发生率比较,差异无统计学意义(P0.05)。结论子宫下段暂时性环扎术治疗前置胎盘分娩术中出血患者,止血效果较好,能迅速降低术中出血量,有效减少患者药物应用及输血量,止血成功率较高,同时子宫坏死等并发症发生率较低,应用安全性较高。  相似文献   
82.
This paper presents a new Bayesian methodology for identifying a transition period for the development of drug resistance to antiretroviral drug or therapy in HIV/AIDS studies or other related fields. Estimation of such a transition period requires an availability of longitudinal data where growth trajectories of a response variable tend to exhibit a gradual change from a declining trend to an increasing trend rather than an abrupt change. We assess this clinically important feature of the longitudinal HIV/AIDS data using the bent‐cable framework within a growth mixture Tobit model. To account for heterogeneity of drug resistance among subjects, the parameters of the bent‐cable growth mixture Tobit model are also allowed to differ by subgroups (subpopulations) of patients classified into latent classes on the basis of trajectories of observed viral load data with skewness and left‐censoring. The proposed methods are illustrated using real data from an AIDS clinical study. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
83.
目的探讨依维莫司联合全反式维甲酸(简称维甲酸)逆转急性早幼粒细胞白血病(APL)细胞株NB4-R1耐药的作用。方法应用CD11b染色流式细胞术及硝基四唑氮蓝(NBT)还原实验检测两药联合应用对细胞分化的影响, 流式细胞术检测细胞周期情况, Annexin V/PI双染色检测细胞凋亡情况, 蛋白质印迹法检测自噬相关蛋白微管结合蛋白轻链3(LC3)、Beclin 1及早幼粒白血病-维甲酸受体融合蛋白(PML-RARα)、磷酸化核糖体S6激酶(P-P70S6K)、磷酸化4E结合蛋白1(P-4E-BP1) 等表达水平。结果与维甲酸组比较, 联用组能诱导耐药细胞株NB4-R1细胞的分化, 并将细胞增殖阻止在G 1期而对细胞凋亡无明显影响。100 nmol/L依维莫司组、1μmol/L维甲酸组、联用组、对照组NB4-R1细胞培养48 h后分化百分率分别为(2.29±0.57)%、(17.06±2.65)%、(54.47±4.91)%、(2.54±0.53)%; 处于G 1期的细胞百分率分别为(35.20±11.97)%、(33.54±6.25)%、(53.70±8.73)%、(27.40±6.01)%; 四组细胞凋亡细胞百分率分别为(2.30±0.14)%、(2.25±0.21)%、(2.40±0.28)%、(1.95±0.07)%。与维甲酸组比较, 联用组mTOR信号通路下游的P70S6K、4E-BP1分子磷酸化水平下降, LC3-II和Beclin 1的表达上调, 且能部分降解融合蛋白PML-RARα。 结论依维莫司联合维甲酸能诱导NB4-R1细胞分化, 且能阻滞细胞周期而不致细胞凋亡, 其机制可能与依维莫司联合维甲酸抑制mTOR信号通路激活自噬作用从而降解PML-RARα蛋白有关。  相似文献   
84.
目的探讨不同剂量乌司他丁对冠状动脉搭桥术患者术后认知功能障碍的影响及其可能的作用机制。方法选择2013年1月至2014年6月在南京医科大学附属南京医院就诊择期行冠状动脉搭桥术的老年患者127例, 分为三组:大剂量乌司他丁组(1.6万U/kg)、小剂量乌司他丁组(0.8万U/kg)和对照组(等容量的生理盐水)。所有患者在手术当日和次日晨8时测血浆皮质醇浓度, 并在术前、开胸、术毕、术后6 h和术后24 h分别检测IL-6、IL-10、TNF-α和S100β蛋白水平。术前1 d、术后1周和3个月分别应用精神神经测试组合量表评估患者认知功能的变化判定有无术后认知功能障碍, 计算各组患者术后认知功能障碍的发生率, 并且比较术后1周是否发生术后认知功能障碍患者S100β蛋白水平。结果最终93例患者完成研究, 三组患者一般资料比较差异均无统计学意义(均 P>0.05)。与术前相比较, 对照组患者术后24 h血浆皮质醇浓度升高明显( P < 0.01), 且大剂量和小剂量乌司他丁组患者术后血浆皮质醇浓度均较对照组低(均 P < 0.01);三组患者术毕、术后6 h和24 h血浆IL-6、IL-10、TNF-α水平及S100β蛋白水平均高于术前(均 P < 0.05);大剂量和小剂量乌司他丁组患者在术毕、术后6 h和24 h血浆IL-6、TNF-α水平浇以及在术后6 h S100β蛋白水平均比相对应时间点的对照组患者降低(均 P < 0.05), 但大剂量和小剂量乌司他丁组患者组间差异无统计学意义( P>0.05)。大剂量和小剂量乌司他丁组患者术后1周认知功能障碍发生率(25.8%和23.3%)均低于对照组(50.0%), 差异有统计学意义(均 P < 0.05);而大剂量和小剂量乌司他丁组术后3个月的术后认知功能障碍发生率(12.9%和16.7%)与对照组(28.1%)比较, 差异均无统计学意义( P>0.05)。术后认知功能障碍组( n=31) 在术后24 h血清S100β蛋白水平高于非术后认知功能障碍组( n=62), 其差异具有统计学意义( P < 0.05)。 结论乌司他丁可降低冠状动脉搭桥术患者术后1周的术后认知功能障碍的发生率, 其机制可能与减轻炎性反应及脑损伤有关。  相似文献   
85.
Purpose: To study polymorphic variants of repair genes in people affected by long-term exposure to radon. The chromosome aberration frequency in peripheral blood lymphocytes was used as the biological marker of genotoxicity.

Materials and methods: Genotyping of 12 single nucleotide polymorphisms in DNA repair genes (APE, XRCC1, OGG1, ADPRT, XpC, XpD, XpG, Lig4 and NBS1) was performed in children with long-term resident exposure to radon. Quantification of the aberrations was performed using light microscopy.

Results: The total frequency of aberrations was increased in carriers of the G/G genotype for the XpD gene (rs13181) polymorphism in recessive model confirmed by the results of ROC-analysis (‘satisfactory predictor’, AUC?=?0.609). Single chromosome fragments frequency was increased in carriers of the G/G genotype in comparison with the T/T genotype. In respect to the total frequency of aberrations, the G/G genotype for the XpG gene (rs17655) polymorphism was also identified as a ‘satisfactory predictor’ (AUC?=?0.605). Carriers of the T/C genotype for the ADPRT gene (rs1136410) polymorphism were characterized by an increased level of single fragments relative to the T/T genotype.

Conclusion: The relationships with several types of cytogenetic damage suggest these three SNP (rs13181, rs17655 and rs1136410) may be considered radiosensitivity markers.  相似文献   
86.
ObjectiveTo describe interval cancers (IC) and the sensitivity of colorectal cancer (CRC) screening programmes.MethodsA systematic review of the literature was conducted through a MEDLINE (PubMed) search. The search strategy combined the terms ‘interval cancer’, ‘false negative’, ‘mass screening’, ‘screening’ ‘early detection of cancer’, ‘colorectal cancer’ and ‘bowel cancer’. Inclusion criteria consisted of population-based screening programmes, original articles written in English or Spanish and publication dates between 1999/01/01 and 2015/02/28. A narrative synthesis of the included articles was performed detailing the characteristics of the screening programmes, the IC rate, and the information sources used in each study.ResultsThirteen articles were included. The episode sensitivity of CRC screening programmes ranged from 42.2% to 65.3% in programmes using the guaiac test and between 59.1% and 87.0% with the immunochemical test. We found a higher proportion of women who were diagnosed with IC and these lesions were mainly located in the proximal colon.ConclusionThere is wide variability in the IC rate in CRC programmes. To ensure comparability between programmes, there is a need for consensus on the working definition of IC and the methods used for their identification and quantification.  相似文献   
87.
ObjectiveTo analyze the impact of individual and market characteristics (such as competition) on the typology of services delivered by a community pharmacy after a recent Portuguese pro-competitive regulatory change.MethodsIn this paper, market concentration indices are used to identify market competition groups in the sample. These competition groups are then described with regard to the typology of services on offer by pharmacies within the group. Finally, a system of structural equations is estimated to verify if the decision of a pharmacy to offer or not to offer each of the studied pharmaceutical services is affected by local market regulated competition.ResultsIn some cases, pharmacies belonging to different competition groups do not present significant differences in terms of the typology of services on offer, but according to our regressions, it seems that vaccines and medicines administration services, pharmaceutical care programmes and medicines management programmes are more likely to be offered in pharmacies located in higher competitive markets. These are also urban areas, in which there is already easy access to products sold in pharmacies, and to health services in general.ConclusionsAccess to additional pharmacy services may in some cases increase as market competition increases. Thus, pro-competitive regulatory measures may have led to an asymmetric distribution of pharmacy services across the country, favouring more competitive urban marketplaces. If policy-makers are interested in a more symmetrical distribution of pharmacies services all over the country, they are recommended to take action to ensure equitable access to these services.  相似文献   
88.
89.
In order to reduce the numbers of medication errors (MEs) that cause adverse reactions (ARs) many authors have tried to identify patient-related risk factors. However, the evidence remains controversial. The aim was to review systematically the evidence on the relationship between patient-related risk factors and the risk of serious ARs. A systematic search in Pubmed, Embase, Cochrane Systematic Reviews, Psychinfo and SweMed+ was performed. Included full text articles were hand searched for further references. Peer reviewed papers including adults from primary and secondary healthcare were included if they clearly defined seriousness of the ARs and described correlations to risk factors by statistical analysis. A total of 28 studies were identified including 85 212 patients with 3385 serious ARs, resulting in an overall frequency of serious ARs in 4% of patients. Age, gender and number of drugs were by far the most frequently investigated risk factors. The total number of drugs was the most consistent correlated risk factor found in both univariate and multivariate analyses. The number of drugs is the most frequently documented independent patient-related risk factor for serious ARs in both the general adult population as well as in the elderly. The existing evidence is however conflicting due to heterogeneity of populations and study methods. The knowledge of patient-related risk factors for experiencing ARs could be used for electronic risk stratification of patients and thereby allocation of healthcare resources to high risk patients.  相似文献   
90.
BackgroundDuring COVID-19 pandemic, a shortage of surgical masks (Mask) and respirators (Resp) was experienced worldwide. We aimed to assess its pattern of use, adverse effects and user errors by Portuguese health care professionals (HCP).MethodsA cross-sectional study was conducted through snowball convenience sample, collected by email/ social media to health care organizations. Participants answered an online anonymous survey in March 2021.ResultsMean age of 3052 respondents was 42.1 years old, 83.6% were female and 77.8% provided direct health care to COVID-19 patients. Mean time of use per shift was 6-8 hours in 40.8% of the participants. 28.0% reported never changing it during their shift. Resp use (vs Mask) was more associated with discomfort (58.2% vs 26.8%), affecting task performance (41.5 vs 18.9%) and communication (55.0 vs 40.9%), dyspnea (36.0 vs 14.4%), skin rash (37.5 vs 19.4%) and headache (37.5 vs 19.4%). Frequent user errors included touching the front while in use (70.1% Mask vs 66.3% Resp) and omitting hand hygiene before (61.8% Mask vs 55.0% Resp) or after use (61.3% Mask vs 57.0% Resp). Average number of errors was higher for Mask (4.3), than for Resp (3.2) (all: P < .001).ConclusionsMost HCP admitted an extended use of Mask/ Resp. Resp were more prone to adverse effects and Mask more prone to errors. Strategies to reinforce good practices should be considered.  相似文献   
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