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1.
This systematic review aims to summarize cognitive reserve (CR) evaluation approaches and to examine the role of seven selected modifiable lifestyle factors (diet, smoking, alcohol consumption, physical activity, cognitive leisure activity, sleep, and meditation) in mitigating the impacts of age- or disease-related brain changes on cognition. Eighteen population-based English empirical studies were included. We summarize the study designs and identify three CR models that were broadly used in these studies, including a residual model assessing lifestyle factors in relation to unexplained variance in cognition after accounting for brain markers, a moderation model testing whether lifestyle factors moderate the relationship between brain status and cognition, and a controlling model examining the associations between lifestyle factors and cognition when controlling for brain measures. We also present the findings for the impact of each lifestyle factor. No studies examined diet, sleep, or meditation, and only two studies focused on smoking and alcohol consumption each. Overall, the studies suggest lifestyle activity factors (physical and cognitive leisure activities) may contribute to CR and attenuate the damaging impact of brain changes on cognition. Standardized measurements of lifestyle factors and CR are needed, and mechanisms underlying CR need to be further addressed as well.  相似文献   
2.
目的 探讨扩散峰度成像(DKI)对Ⅰ型与Ⅱ型上皮性卵巢癌(EOC)的鉴别诊断价值。 方法 回顾性收集经手术病理证实的45例EOC病人的临床、病理及影像资料,平均年龄(50±13)岁。根据术后病理结果对EOC病人进行分组,分为Ⅰ型组(24例)和Ⅱ型组(21例)。所有病人均于术前行盆腔DKI检查,由2名放射科医师在DKI各参数伪彩图上分别测量平均扩散峰度(MK)、平行扩散峰度(Ka)、垂直扩散峰度(Kr)、平均扩散系数(MD)、平行扩散系数(Da)、垂直扩散系数(Dr)、各向异性分数(FA)、峰度各向异性分数(FAk)。采用Fisher确切概率检验、独立样本t检验或Mann-Whitney U检验比较2组间临床、病理及影像资料的差异,对差异有统计学意义的参数绘制受试者操作特征(ROC)曲线,分析其鉴别诊断效能。 结果 病理表现上,Ⅰ型中交界性肿瘤占比最高(50.0%),Ⅱ型中浆液性癌占比最高(61.9%);Ⅰ型中高分化癌占50%,Ⅱ型多表现为中低分化癌 (76.2%),Ⅰ型EOC的分化程度高于Ⅱ型;Ⅰ型多数处于Ⅰ期(79.2%),Ⅱ型多处于Ⅲ期(57.1%)(均P<0.05)。MRI影像上, Ⅰ型病灶多表现为囊性(41.7%)或囊实性(33.3%),Ⅱ型多表现为实性(52.3%);Ⅱ型(66.7%)腹水发生率高于Ⅰ型(29.2%)(均P<0.05)。Ⅰ型的MK、Ka和Kr值低于Ⅱ型,MD、Da和Dr值高于Ⅱ型(均P<0.05)。ROC曲线分析显示,MK阈值为0.504时,鉴别2组诊断的曲线下面积(AUC,0.817)最大,诊断敏感度(95.2%)、阴性预测值(92.9%)、准确度(78.9%)也最高,Da阈值为2.190时鉴别诊断的AUC(0.770)最小,而特异度(76.2%)、阳性预测值(75.9%)最高。 结论 DKI序列的定量参数MK、Ka、Kr、MD、Da及Dr均有助于鉴别Ⅰ型与Ⅱ型EOC,其中MK值鉴别诊断效能更大。  相似文献   
3.
IntroductionSurgery is the cornerstone of the treatment for advanced ovarian cancer. Reaching complete cytoreduction resulting in no gross residual disease often requires complex surgery. The aim of this study was to assess the impact of increased surgical radicality on the risk of complications in the treatment of advanced ovarian cancer.Materials and methodsAll consecutive patients with advanced ovarian cancer (FIGO Stage IIIB-IVB) who had undergone primary or interval debulking surgery during a six-year study period were identified. In the midst of the study period, a surgical practice change towards maximal surgical effort occurred. Two groups were formed for the analysis: cohort A, that consisted of patients operated before the surgical paradigm shift and cohort B, that consisted of patients operated under the period of increased surgical radicality.Results252 patients were included in the analysis. Complete resection (R0) was achieved in 21.3% of surgeries in cohort A and in 51.2% in cohort B. The total postoperative complication rate was 76.2%. Most of the complications (86.5%) were minor (Clavien-Dindo I-IIIA). The patients in cohort B were at increased risk for complications, OR 2.94 (95%CI 1.58–5.47; p = 0.001). As for the approach to cytoreduction (primary vs. interval debulking), there was no statistically significant association with the occurrence of postoperative complications (p = 0.659).ConclusionIn the present study more extensive surgeries led to better surgical results but increased postoperative morbidity. Postoperative complication rates were similar in both primary and interval debulking surgeries.  相似文献   
4.
BackgroundThe role of change in fractional flow reserve derived from CT (FFRCT) across coronary stenoses (ΔFFRCT) in guiding downstream testing in patients with stable coronary artery disease (CAD) is unknown.ObjectivesTo investigate the incremental value of ΔFFRCT in predicting early revascularization and improving efficiency of catheter laboratory utilization.MaterialsPatients with CAD on coronary CT angiography (CCTA) were enrolled in an international multicenter registry. Stenosis severity was assessed as per CAD-Reporting and Data System (CAD-RADS), and lesion-specific FFRCT was measured 2 ?cm distal to stenosis. ΔFFRCT was manually measured as the difference of FFRCT across visible stenosis.ResultsOf 4730 patients (66 ?± ?10 years; 34% female), 42.7% underwent ICA and 24.7% underwent early revascularization. ΔFFRCT remained an independent predictor for early revascularization (odds ratio per 0.05 increase [95% confidence interval], 1.31 [1.26–1.35]; p ?< ?0.001) after adjusting for risk factors, stenosis features, and lesion-specific FFRCT. Among the 3 models (model 1: risk factors ?+ ?stenosis type and location ?+ ?CAD-RADS; model 2: model 1 ?+ ?FFRCT; model 3: model 2 ?+ ?ΔFFRCT), model 3 improved discrimination compared to model 2 (area under the curve, 0.87 [0.86–0.88] vs 0.85 [0.84–0.86]; p ?< ?0.001), with the greatest incremental value for FFRCT 0.71–0.80. ΔFFRCT of 0.13 was the optimal cut-off as determined by the Youden index. In patients with CAD-RADS ≥3 and lesion-specific FFRCT ≤0.8, a diagnostic strategy incorporating ΔFFRCT >0.13, would potentially reduce ICA by 32.2% (1638–1110, p ?< ?0.001) and improve the revascularization to ICA ratio from 65.2% to 73.1%.ConclusionsΔFFRCT improves the discrimination of patients who underwent early revascularization compared to a standard diagnostic strategy of CCTA with FFRCT, particularly for those with FFRCT 0.71–0.80. ΔFFRCT has the potential to aid decision-making for ICA referral and improve efficiency of catheter laboratory utilization.  相似文献   
5.
背景卵巢低反应(POR)患者较差的妊娠结局一直是生殖医学领域难题之一,但目前关于年龄对POR患者辅助生殖技术(ART)治疗后活产率的阈值效应的研究少见。目的分析年龄对POR患者ART治疗后活产率的影响及其阈值效应。方法商丘市第一人民医院妇产科和新疆医科大学第一附属医院生殖助孕中心2014年8月至2018年12月共收治接受常规体外授精/卵胞质内单精子注射-胚胎移植(IVF/ICSI)助孕治疗的女性共19 185例,选取其中诊断为POR者共3 337例为研究对象。所有患者采用控制性促排卵方案,同时采用IVF/ICSI进行胚胎移植并给予黄体支持治疗。分析所有患者活产婴儿情况,年龄对POR患者ART治疗后活产婴儿的影响采用单因素和多因素Logistic回归分析,并建立平滑拟合曲线、进行阈值效应分析。结果3 337例POR患者ART治疗后活产婴儿1 134例,未活产婴儿2 203例,活产率为33.98%(1 134/3 337)。多因素Logistic回归分析结果显示,年龄是POR患者ART治疗后活产婴儿的独立影响因素〔OR=0.920,95%CI(0.902,0.939),P<0.01〕。建立平滑拟合曲线发现,年龄与POR患者ART治疗后活产率呈负相关,但二者之间并非简单的线性关系;阈值效应分析结果显示,POR患者ART治疗后活产率下降的折点为32岁,即年龄≤32岁的POR患者ART治疗后活产率不受年龄影响〔OR=1.000,95%CI(0.998,1.012),P=0.38〕,但年龄>32岁的POR患者ART治疗后活产率随年龄增长而降低〔OR=0.800,95%CI(0.799,0.823),P<0.01〕。结论年龄是POR患者ART治疗后活产婴儿的独立影响因素,年龄>32岁的POR患者ART治疗后活产率随年龄增长而降低。  相似文献   
6.
目的 探讨基于深度学习的CT血流储备分数(FFRCT)在可疑冠心病病人中应用的可行性,分析缺血性病变(FFRCT≤0.80)的预测因素及对治疗决策的影响。方法 回顾性纳入因疑似冠心病行冠状动脉CT血管成像(CCTA)的病人292例,其中男187例,女105例,平均年龄(65.8±10.3)岁。利用CCTA影像将狭窄程度分为轻度 (≥25%且<50%)、中度(≥50%且<70%)和重度(≥70%且<99%)。采用基于深度学习的FFRCT软件对病人的CCTA数据进行测量。根据FFRCT数值范围将病人分为阳性组(FFRCT≤0.80,102例)和阴性组(FFRCT>0.80,190例)。2组病人的一般资料、CCTA上的血管特征及血运重建,以及基于FFRCT与CCTA制定的治疗策略的比较采用Mann-Whitney U 检验、t检验及卡方检验。采用Logistic回归分析FFRCT≤0.80的独立预测因素。结果 阳性组病人的年龄更大,男性更多,高血压、糖尿病和吸烟的比例均高于阴性组(均P<0.05)。阳性组较阴性组病人更多的表现为中重度狭窄(分别为80.4%和28.4%),更多的病人行血运重建术(分别为56.8%和11.1%),均P<0.05。74例病人(25.3%)基于FFRCT的结果治疗决策发生改变。多因素Logsitic回归分析显示,高血压(OR=2.245)、糖尿病(OR=2.238)及中重度狭窄(OR=8.837)是FFRCT≤0.80的独立预测因素(均P<0.05)。结论 基于深度学习的FFRCT技术在可疑冠心病病人中的应用是可行的,高血压、糖尿病及中重度狭窄是FFRCT≤0.80的独立预测因素,FFRCT可能影响病人的治疗决策。  相似文献   
7.
卵巢囊肿(ovarian cyst)是妇科常见疾病,可发生于任何年龄段,以育龄期最为多见。卵巢囊肿多为良性,除个别因扭转、破裂等表现为急腹症外,一般无特异性症状。部分功能性卵巢囊肿可伴有月经紊乱、腹部不适等症状,多数随着囊肿的消退而逐渐消失。  相似文献   
8.
目的探讨PCOS患者血清中血小板反应蛋白-1(TSP-1)表达水平与卵巢间质血供之间的关系,以及TSP-1对体外培养的人卵巢微血管内皮细胞(HOMEC)增殖能力的影响。方法选取2018年10月至2019年10月在我院生殖中心就诊的女性,50例诊断为PCOS的患者纳入PCOS组,50例因男方因素不孕的健康女性纳入对照组。ELISA法用于测定所有入组患者血清中的TSP-1水平。在患者处于卵泡早期时,经阴道超声测量双卵巢间质血供,计算血流动力学参数搏动指数(PI)和阻力指数(RI)。体外培养HOMEC,在不同浓度TSP-1(10-9 mmol/L、10-10 mmol/L和10-11 mmol/L)处理细胞12 h、24 h、48 h后,用CCK-8检测细胞增殖情况。结果PCOS组血清LH、T水平及LH/FSH均显著高于对照组(P<0.05)。与对照组比较,PCOS组血清TSP-1水平显著降低(P<0.05),卵巢间质血流动力学参数RI、PI值均显著降低(P<0.05)。Pearson相关性分析发现血清TSP-1水平与卵巢间质血流RI、PI均呈显著正相关(分别为r=0.83,P<0.05;r=0.85,P<0.05)。CCK-8实验显示,与对照组比较,不同浓度(10-11 mmol/L、10-10 mmol/L、10-9 mmol/L)TSP-1作用12 h、24 h、48 h后,对HOMEC增殖的抑制率均显著升高(P<0.05)。在TSP-1各浓度组,TSP-1作用24 h、48 h对HOMEC的抑制率均较作用12 h显著升高(P<0.05),且24 h时达到峰值。结论PCOS患者血清中TSP-1表达降低,卵巢间质血流动力学参数RI、PI值显著降低,卵巢间质血流量丰富,且TSP-1与RI、PI值呈正相关。TSP-1抑制HOMEC增殖,可能参与负调控血管生成。  相似文献   
9.
10.

Background

Advanced low-grade ovarian carcinoma (LGOC) is difficult to treat. In several studies, high estrogen receptor (ER) protein expression was observed in patients with LGOC, which suggests that antihormonal therapy (AHT) is a treatment option. However, only a subgroup of patients respond to AHT, and this response cannot be adequately predicted by currently used immunohistochemistry (IHC). A possible explanation is that IHC only takes the ligand, but not the activity, of the whole signal transduction pathway (STP) into account. Therefore, in this study, the authors assessed whether functional STP activity can be an alternative tool to predict response to AHT in LGOC.

Methods

Tumor tissue samples were obtained from patients with primary or recurrent LGOC who subsequently received AHT. Histoscores of ER and progesterone receptor (PR) were determined. In addition, STP activity of the ER STP and of six other STPs known to play a role in ovarian cancer was assessed and compared with the STP activity of healthy postmenopausal fallopian tube epithelium.

Results

Patients who had normal ER STP activity had a progression-free survival (PFS) of 16.1 months. This was significantly shorter in patients who had low and very high ER STP activity, with a median PFS of 6.0 and 2.1 months, respectively (p < .001). Unlike ER histoscores, PR histoscores were strongly correlated to the ER STP activity and thus to PFS.

Conclusions

Aberrant low and very high functional ER STP activity and low PR histoscores in patients with LGOC indicate decreased response to AHT. ER IHC is not representative of functional ER STP activity and is not related to PFS.  相似文献   
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