中医治未病与慢性疲劳综合征的防治

阐述慢性疲劳综合征及中医＂未病学＂的概念,以及中医＂治未病＂思想在防治慢性疲劳综合征方面的独特优势,防治疲劳状态体现出的预防为主、防重于治的指导思想与中医＂治未病＂的医学思想不谋而合。     

Determinants of the tension-time index of inspiratory muscles in children with cystic fibrosis

Nutritional status and chronic pulmonary hyperinflation can alter respiratory muscle function in cystic fibrosis (CF). This study investigated: 1) whether inspiratory muscle function is reduced in children with stable CF in comparison with healthy controls; and 2) the mechanisms leading to inspiratory muscle weakness, which probably predispose to respiratory muscle fatigue. We determined the tension-time index of the inspiratory muscles (T_TMUS) noninvasively at rest in 16 children with mild to moderate CF (mean age, 11 ± 2 years) and 10 healthy controls (mean age, 11 ± 2 years). The T_TMUS was determined as follows: T_TMUS = T_I/T_TOT · P_I/P_IMAX, where P_I is the mean inspiratory pressure estimated from the measure of mouth occlusion pressure (P0.1), P_IMAX is the maximal inspiratory pressure, and T_I/T_TOT is the duty cycle. The results showed similar nutritional status in both groups, as well as mild to moderate airway obstruction, hyperinflation, and trapped gas in the CF group. In this group only, a significant inverse relationship was found between T₁/T_TOT and P₁/P_IMAX[T_IT_TOT = 0.482 - (0.388P_I/P_IMAX), r = −0.53; p < 0.05]. The patients also had a greater T_TMUS (T_TMUS = 0.087 ± 0.030 in CF vs. 0.056 ± 0.014 in controls, P < 0.01) that increased with decreasing lean body mass (r = −0.70, P < 0.005), with increasing percent predicted functional residual capacity (r = 0.70, P < 0.05). and increasing volumes of trapped gas (r = 0.77, P < 0.01). The multiple linear regression analysis for these factors was significant (R² = 0.84, P < 0.01); however, the partial regression coefficient was significant only for lean body mass (r² = 0.60, P < 0.05). Therefore, muscle mass appeared as the strongest determinant of T_TMUS in CF. This study used a noninvasive method to assess the inspiratory muscle performance in children with CF. The results suggest impairment in inspiratory muscle function in these children despite good nutritional status and only mild to moderate alteration in pulmonary function tests. In addition, we were able to investigate some of the determinants of inspiratory muscle weakness, namely, muscle mass, hyperinflation, and trapped gas, and found that muscle mass played a predominant role. Pediatr. Pulmonol. 1997; 23:336–343. © 1997 Wiley-Liss, Inc.     

针灸治疗慢性疲劳综合征39例

目的观察针灸治疗慢性疲劳综合征的疗效。方法运用中医学的整体观念,进行辨证论治,主穴取百会、足三里、三阴交、关元穴,治疗慢性疲劳综合征39例。结果临床治愈20．5％,显效56．4％,有效12．8％,无效10．3％,总有效率89．7％。结论针灸是一种治疗慢性疲劳综合征的有效治疗方法。     

Experimental and Numerical Investigations on High Performance SFRC: Cyclic Tensile Loading and Fatigue

In the present study, the capability of high-strength short steel fibers to control the degradation in high-performance concrete was experimentally examined and numerically simulated. To this end, notched prismatic high-performance concrete specimens with (HPSFRC) and without (HPC) short steel fibers were subjected to static and cyclic tensile tests up to 100,000 cycles. The cyclic tests showed that the rate of strain increase was lower for HPSFRC specimens and that the strain stagnated after around 10,000 cycles, which was not the case with HPC specimens. The microscopic examinations showed that in HPSFRC, a larger number of microcracks developed, but they had a smaller total surface area than the microcracks in the HPC. To further investigate the influence of fibers on the behavior of HPSFRC in the cracked state, displacement-controlled crack opening tests, as well as numerical simulations thereof, were carried out. Experiments have shown, and the numerical simulations have confirmed, that the inclusion of short steel fibers did not significantly affect the ultimate strength; however, it notably increased the post-cracking ductility of the material. Finally, the unloading/reloading behavior was examined, and it was observed that the unloading stiffness was stable even for significant crack openings; however, the hysteresis loops due to unloading/reloading were very small.     

Fatigue Behavior of an AM50 Die-Casting Alloy Anodized by Plasma Electrolytic Oxidation

While an anodizing process is essential for magnesium alloys to be used under corrosive environments, it sometimes stimulates a fatigue fracture that initiates at the interface between the coating layer and the substrate. In this study, a plasma electrolyte oxidation (PEO) technique was employed to provide excellent adhesion between the anodizing layer and the AM50 die-cast by applying an extremely high dielectric discharge in an alkaline phosphate electrolyte, and its effect on corrosion and fatigue behaviors was investigated. The stress intensity factor at the fatigue limit was estimated to be 0.28 MPam^0.5. The specimen anodized using the PEO technique exhibits enhanced strength and corrosion resistance compared to the unanodized counterpart. Furthermore, it shows a relative fatigue life in spite of the thick anodizing layer because the crack initiates from the interface, not from the pore near the interface.     

Experiences of fatigue and depression before and after low-dose 1-thyroxine supplementation in essentially euthyroid individuals

Hypothyroidism is a relative state, long associated with fatigue and depression. Individuals may experience thyroid-related symptoms such as fatigue and depression before thyroid indices become abnormal. However, because of clinicians' diverse interpretations of appropriate circumstances for its use, low-dose, 1-thyroxine supplementation often is overlooked as a therapeutic agent for symptom treatment. The purpose of this exploratory, hermeneutic study was to describe euthyroid individuals' experiences of fatigue and depression before and after low-dose 1-thyroxine supplementation. For women participants, the collective influence of fatigue and depression prior to treatment interfered significantly with their day-to-day lives, despite their euthyroid status. For men, the influence of symptoms was far less substantial than for women. In general, participants responded favorably, both physically and emotionally, to low-dose 1-thyroxine supplementation. Furthermore, no participant experienced 1-thyroxine induced hyperthyroidism or untoward side effects attributable to 1-thyroxine. Further study of effects of 1-thyroxine on symptoms is needed. © 1997 John Wiley & Sons, Inc. Res Nurs Health 20: 389–398, 1997     

Vitamin D Supplementation and Mental Health in Multiple Sclerosis Patients: A Systematic Review

Vitamin D has a promising role in multiple sclerosis (MS) management, and it has been found to be beneficial for patients’ mental health, which is reduced in MS patients. The aim of the present study was to conduct a systematic review of the literature to assess the influence of vitamin D supplementation on mental health in MS patients. The systematic review was registered in the PROSPERO database (CRD42020155779) and it was conducted on the basis of the PRISMA guidelines. The search procedure was conducted using PubMed and Web of Science databases and it included studies published up until September 2021. Six studies were included in the systematic review. The risk of bias was analyzed using the Newcastle–Ottawa Scale (NOS). Within the included studies, there were two studies randomized against placebo and four other prospective studies. The studies presented vitamin D interventions randomized against placebo or not randomized, while supplementation was applied for various durations—from 4 weeks to 12 months, or the studies compared patients who applied vitamin D supplementation and those who did not apply it and verified the effect of the supplementation after a number of years. The mental health outcomes that were assessed included quality of life, depression/depressive symptoms, and fatigue as an additional element. The majority of studies supported the positive influence of vitamin D on the mental health of MS patients, including the study characterized as having the highest quality (randomized against placebo with the highest NOS score). All the studies that assessed the quality of life indicated the positive influence of vitamin D while the studies that did not find a positive influence of vitamin D were conducted for depression/depressive symptoms. In spite of the fact that only a small number of studies have been conducted so far, and only two studies were randomized against a placebo, some conclusions may be formulated. The systematic review allowed us to conclude that there may be a positive effect of vitamin D supplementation in MS patients, which was stated in all of the studies analyzing quality of life, as well as in one study analyzing depressive symptoms. Considering that vitamin D deficiency is common in MS patients, and the potential positive influence of supplementation on the quality of life, supplementation should be applied at least in doses that cover the recommended intake.     

The effects of ephedrine on the development of fatigue in a prolonged driving‐related task

The effects of ephedrine on the development of fatigue in a prolonged driving‐related task were investigated using three independent measures. Subjects (n=15) received either ephedrine (60 mg) or a placebo before carrying out a 3‐way divided attention task for an uninterrupted 4 h period, during which cardiac inter‐beat interval was monitored. A battery of psychomotor tests and two questionnaires were completed before and after the 4 h session and oral temperature, blood pressure and heart rate were also recorded. A saliva sample was taken at 4 h for ephedrine assay. The performance of the placebo group on the prolonged task deteriorated over time, whereas that of the ephedrine group improved. In placebo subjects, there was a progressive decrease in heart rate, an increase in heart rate variability (HRV) and an increase in the peak log spectral power of the blood pressure frequency component of HRV. Deterioration of performance on the test battery and questionnaires confirmed that fatigue had developed. The mean salivary ephedrine concentration after 4 h was 0·08 mg/ml (±0·03 SEM). The deterioration in performance in the placebo group indicated the development of fatigue which was partially offset by a single therapeutic dose of ephedrine. Copyright © 1999 John Wiley & Sons, Ltd.     

Influence of Changes in the Shape of the Anode Channel in Polymer Electrolyte Fuel Cell on the Loss of Its Service Life

The fuel cell operation is associated with significant current density and durability problems, among other anode collectors. We used a numerical model based on flows with chemical reactions in a porous medium to solve these problems. We tested four variants of the anode channels. In the shape of the anode channel, we introduced changes to improve the current density. We also examined the influence of the channel shape on the stress field and rheological processes in the casing material. We verified the numerical model on the experimental data. Furthermore, we corrected the amount of the hydrogen stream and the produced water in the whole range of the cell’s operation. The test results show that it is possible to increase the current density in all operating fields of the fuel cell while maintaining a low mechanical load on graphite elements and their safe operation time.     

Renal medication-related clinical decision support (CDS) alerts and overrides in the inpatient setting following implementation of a commercial electronic health record: implications for designing more effective alerts

ObjectiveTo assess the appropriateness of medication-related clinical decision support (CDS) alerts associated with renal insufficiency and the potential/actual harm from overriding the alerts.Materials and MethodsOverride rate frequency was recorded for all inpatients who had a renal CDS alert trigger between 05/2017 and 04/2018. Two random samples of 300 for each of 2 types of medication-related CDS alerts associated with renal insufficiency—“dose change” and “avoid medication”—were evaluated by 2 independent reviewers using predetermined criteria for appropriateness of alert trigger, appropriateness of override, and patient harm.ResultsWe identified 37 100 “dose change” and 5095 “avoid medication” alerts in the population evaluated, and 100% of each were overridden. Dose change triggers were classified as 12.5% appropriate and overrides of these alerts classified as 90.5% appropriate. Avoid medication triggers were classified as 29.6% appropriate and overrides 76.5% appropriate. We identified 5 adverse drug events, and, of these, 4 of the 5 were due to inappropriately overridden alerts.ConclusionAlerts were nearly always presented inappropriately and were all overridden during the 1-year period studied. Alert fatigue resulting from receiving too many poor-quality alerts may result in failure to recognize errors that could lead to patient harm. Although medication-related CDS alerts associated with renal insufficiency had previously been found to be the most clinically beneficial alerts in a legacy system, in this system they were ineffective. These findings underscore the need for improvements in alert design, implementation, and monitoring of alert performance to make alerts more patient-specific and clinically appropriate.