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Objective. Ischemic preconditioning (IPC) has gradually been promoted in clinical practice to lower the risk of cardiovascular surgery and postoperative complications. We investigated the role of IPC on vascular endothelial function and the relationship between IPC, flow-mediated dilation (FMD), and brachial artery diameter (BAD). Methods. Systematic searches were conducted in PubMed, Medline, Cochrane Library, Embase, and Scopus databases from their inception to March 20, 2020. This research included randomized controlled trials (RCTs) with adults, and the values of FMD and BAD were considered as the primary outcomes. Ten studies comprising 292 participants were included in the meta-analysis. Results. Regarding FMD, we observed beneficial effects of IPC on endothelial function (standardized mean difference (SMD): 1.82; 95% confidence interval (CI): 0.64, 3.01; p < 0.001 ; I2 = 89.9%). However, the available evidence did not indicate that IPC affected BAD (SMD: 0.08; 95% CI: −0.03, 0.18; p > 0.05 ; I2 = 76.5%). Conclusions. Our meta-analysis indicated a significant effect of IPC on the endothelial function of the blood vessels, affecting FMD but not BAD.

For Electrocardiograph (ECG) detection, the analog front-end (AFE) needs to distinguish the signals with high amplitude fluctuation, in which normally an ADC with 10 to 12 bit resolution with high dynamic range (DR) is required. In this paper, an input-adaptive control logic is proposed and implemented, which enables AFE to regulate the gain of amplifier according to the amplitude of input signal, which enables an 8-bit SAR ADC reaching 67.6 dB DR near the common-mode level. This design relies on the powerful backend calibration process that the design difficulty of the analog end is converted to the digital back end, which is a good and practical way in nowadays. The proposed structure is implemented with a 0.18\ \mu\mathrm{m}$ standard CMOS process. Measurement results show that the SNDR remains basically unchanged when the input amplitude decreases by a range from 6 dB to 35 dB, and the DR is boosted by 20.3 dB compared with the conventional 8-bit SAR ADC. The ADC and extra control logic consume 8.4 nW under 1 V supply at a sampling rate of 500 S/s.

A questionnaire designed to detect Parkinson's disease (PD) was developed by Tanner et al. in 1990. It consists of nine symptom questions and has been tested in several languages. We investigated the validity of the questionnaire in a Chinese population. Because handwriting is not common for elderly Chinese people, item 2 about "smaller handwriting" may be of no use, thus we also computed the performance of the questionnaire without item 2. The questionnaire was administered face-to-face to all 59 PD patients registered in our hospital and 217 non-neurological outpatients from the same hospital. All 217 outpatients were offered a short interview and examination related to PD. Of the 59 PD patients, 47 participated the study. None of the 217 non-neurological outpatients was diagnosed with parkinsonism. A combination of any three questions yielded the best balance between sensitivity (93.6%) and specificity (88.9%). There was no difference in validity between the questionnaire with and without item 2. This symptom questionnaire is an appropriate instrument to identify PD in a Chinese population. The questionnaire without item 2 is also satisfactory as a screening instrument to detect PD and may be more suitable for areas with a high illiteracy rate.