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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   
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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   
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随着人口老龄化和生育力的下降,我国放开了三孩政策,对有生育要求的夫妇进行生育力评估显得非常必要。女性生育力与年龄关系密切,还依赖于卵巢、输卵管、子宫等生殖器官。本文就影响女性生育力的因素进行介绍。  相似文献   
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Background: Even key opinion leaders now concede that electronic fetal monitoring (EFM) cannot reliably identify fetal acidemia which many vouch as the only labor mediated pathophysiologic precursor for cerebral palsy (CP). We have developed the “Fetal Reserve Index” – an algorithm combining five dynamic components of EFM (1. Rate, 2. Variability, 3. Accelerations, 4. Decelerations, and 5. Excessive uterine activity) considered individually that are combined with the presence of: 6. maternal, 7. obstetrical, and 8. fetal risk factors.

Objective: Here, we compare this 8-point fetal reserve index (FRI) against the performance of ACOG monograph criteria and ACOG Category systems for predicting risk for both CP and the need for emergency operative delivery (EOD). We then studied how varied management for screen positives (Red zone-defined below) impacts the outcome of such cases.

Study design: Four hundred twenty term patients were studied: all entered labor with normal EFMs and no apparent cause of harm except events of labor and delivery. Sixty subsequently developed CP, and 360 were apparently normal controls. An FRI, normal on all eight parameters scored 100%, 4 of the 8 was 50%, etc. We divided cases into Green zone >50%, Yellow 50–26%, and Red ≤25%. An FRI in the Red zone was considered a positive screen. We then compared performance metrics for the three evaluation schemes and differences between controls that reached Red against those controls whose worst scores were Green/Yellow.

Results: For detection of injury during labor, the FRI performed much better than the ACOG Category criteria (sensitivity 28%), and Category III (45%) (p?Conclusions: FRI shows better discrimination for adverse fetal outcome and EOD than traditional EFM interpretation. The Category system is a very poor, subjective screening method as the vast majority of CP babies never reach the “action point” result of Category III. While reaching the Red zone does not ordain a bad outcome, how it is managed, does. Compared to CP cases, Red controls were delivered faster, had higher FRIs, and often had prompt management including IR maneuvers, which improved the FRI and lowered the risk of EODs even for cases with normal outcomes. With further study and validation, the quantitative FRI approach may replace the current, very subjective interpretation with a quantitative “lab test” approach.  相似文献   
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BackgroundCompared with invasive fractional flow reserve (FFR), coronary CT angiography (cCTA) is limited in detecting hemodynamically relevant lesions. cCTA-based FFR (CT-FFR) is an approach to overcome this insufficiency by use of computational fluid dynamics. Applying recent innovations in computer science, a machine learning (ML) method for CT-FFR derivation was introduced and showed improved diagnostic performance compared to cCTA alone. We sought to investigate the influence of stenosis location in the coronary artery system on the performance of ML-CT-FFR in a large, multicenter cohort.MethodsThree hundred and thirty patients (75.2% male, median age 63 years) with 502 coronary artery stenoses were included in this substudy of the MACHINE (Machine Learning Based CT Angiography Derived FFR: A Multi-Center Registry) registry. Correlation of ML-CT-FFR with the invasive reference standard FFR was assessed and pooled diagnostic performance of ML-CT-FFR and cCTA was determined separately for the following stenosis locations: RCA, LAD, LCX, proximal, middle, and distal vessel segments.ResultsML-CT-FFR correlated well with invasive FFR across the different stenosis locations. Per-lesion analysis revealed improved diagnostic accuracy of ML-CT-FFR compared with conventional cCTA for stenoses in the RCA (71.8% [95% confidence interval, 63.0%–79.5%] vs. 54.8% [45.7%–63.8%]), LAD (79.3 [73.9–84.0] vs. 59.6 [53.5–65.6]), LCX (84.1 [76.0–90.3] vs. 63.7 [54.1–72.6]), proximal (81.5 [74.6–87.1] vs. 63.8 [55.9–71.2]), middle (81.2 [75.7–85.9] vs. 59.4 [53.0–65.6]) and distal stenosis location (67.4 [57.0–76.6] vs. 51.6 [41.1–62.0]).ConclusionIn a multicenter cohort with high disease prevalence, ML-CT-FFR offered improved diagnostic performance over cCTA for detecting hemodynamically relevant stenoses regardless of their location.  相似文献   
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目的研究疏肝补肾汤联合双丹养血胶囊治疗多囊卵巢综合征(PCOS)对患者卵巢储备和受孕功能的影响结局。方法选取PCOS患者96例,按照门诊就诊顺序,根据单双号分为研究组和对照组,每组48例。对照组予枸橼酸氯米芬胶囊,观察组予疏肝补肾汤与双丹养血胶囊,3个月经周期为1个疗程,连续2个疗程。比较两组研究对象治疗前及治疗后卵巢储备功能[基础卵泡刺激素(bFSH)、基础雌二醇(bE2)、抗苗勒氏管激素(AMH)水平、基础窦卵泡计数(AFC)]、卵泡状况(卵泡直径、体积)、卵巢间质血流动力学指数[搏动指数(RI)、阻力指数(PI)]和随访半年受孕率及不良事件率。结果研究组排卵率77.08%,低于对照组的81.25%,但差异无统计学意义(P>0.05);受孕率72.92%高于对照组的41.67%,差异有统计学意义(P<0.05)。治疗后,研究组bFSH水平低于对照组,bE2、AMH水平高于对照组,差异均有统计学意义(P<0.05);且治疗后两组研究对象bFSH水平均低于同组治疗前,bE2、AMH水平高于同组治疗前,差异均有统计学意义(P<0.05)。治疗后,研究组卵巢体积、卵泡数量、PI水平低于对照组,优势卵泡直径、RI水平高于对照组,差异均有统计学意义(P<0.05);且治疗后研究组卵巢体积、卵泡数量、PI水平低于同组治疗前,优势卵泡直径、RI水平高于同组治疗前,差异均有统计学意义(P<0.05);治疗后对照组卵泡数量少于同组治疗前,差异均有统计学意义(P<0.05);而优势卵泡直径、RI高于同组治疗前,卵巢体积、PI小于同组治疗前,但差异无统计学意义(P>0.05)。随访半年研究组不良事件3例、发生率6.25%,对照组11例、发生率22.92%,二者比较差异有统计学意义(χ^2=4.751,P<0.05)。结论疏肝补肾汤联合双丹养血胶囊能有效改善PCOS患者卵巢储备功能,利于提高患者受孕率,且效果显著、安全可靠。  相似文献   
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