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121.
International Journal of Mental Health and Addiction - The presence of COVID-19 has had psychological consequences among health personnel; these include fear, anxiety, and depression. In the...  相似文献   
122.
Voriconazole use has increased since the drug's introduction in 2002, and new and unique adverse effects are emerging as patients undergo prolonged therapy. Most concerning is the increased risk of cutaneous malignancies, primarily squamous cell carcinoma (SCC); this risk is duration dependent and the associated malignancies tend to be more aggressive and multifocal. Voriconazole is also associated with phototoxicity (which may be a precursor to malignancy), periostitis, hallucinations and encephalopathy, peripheral neuropathy, alopecia, nail changes, hyponatremia, and other adverse effects. Some toxicities (neuropsychiatric and gastrointestinal including hepatic) are seen in clear association with supratherapeutic serum voriconazole levels; thus, careful monitoring of voriconazole levels is a critical component of safe drug use. Guidelines for screening for adverse effects after long‐term voriconazole use may be beneficial and need to be established.  相似文献   
123.
Somewhat paradoxically, fracture risk, which depends on applied loads and bone strength, is elevated in both anorexia nervosa and obesity at certain skeletal sites. Factor‐of‐risk (Φ), the ratio of applied load to bone strength, is a biomechanically based method to estimate fracture risk; theoretically, higher Φ reflects increased fracture risk. We estimated vertebral strength (linear combination of integral volumetric bone mineral density [Int.vBMD] and cross‐sectional area from quantitative computed tomography [QCT]), vertebral compressive loads, and Φ at L4 in 176 women (65 anorexia nervosa, 45 lean controls, and 66 obese). Using biomechanical models, applied loads were estimated for: 1) standing; 2) arms flexed 90°, holding 5 kg in each hand (holding); 3) 45° trunk flexion, 5 kg in each hand (lifting); 4) 20° trunk right lateral bend, 10 kg in right hand (bending). We also investigated associations of Int.vBMD and vertebral strength with lean mass (from dual‐energy X‐ray absorptiometry [DXA]) and visceral adipose tissue (VAT, from QCT). Women with anorexia nervosa had lower, whereas obese women had similar, Int.vBMD and estimated vertebral strength compared with controls. Vertebral loads were highest in obesity and lowest in anorexia nervosa for standing, holding, and lifting (p < 0.0001) but were highest in anorexia nervosa for bending (p < 0.02). Obese women had highest Φ for standing and lifting, whereas women with anorexia nervosa had highest Φ for bending (p < 0.0001). Obese and anorexia nervosa subjects had higher Φ for holding than controls (p < 0.03). Int.vBMD and estimated vertebral strength were associated positively with lean mass (R = 0.28 to 0.45, p ≤ 0.0001) in all groups combined and negatively with VAT (R = –[0.36 to 0.38], p < 0.003) within the obese group. Therefore, women with anorexia nervosa had higher estimated vertebral fracture risk (Φ) for holding and bending because of inferior vertebral strength. Despite similar vertebral strength as controls, obese women had higher vertebral fracture risk for standing, holding, and lifting because of higher applied loads from higher body weight. Examining the load‐to‐strength ratio helps explain increased fracture risk in both low‐weight and obese women. © 2015 American Society for Bone and Mineral Research.  相似文献   
124.
Accurate assessment of ventricular function is particularly important in children with hypoplastic left heart syndrome (HLHS) after completion of the total cavopulmonary connection (TCPC). For this purpose, two-dimensional speckle tracking (2DST) is a promising technique as it does not depend on the angle of insonation or the geometry of the ventricle. The objective of this study was to assess changes in systolic and diastolic right ventricular (RV) function within a 5-year follow-up period of HLHS patients after TCPC using conventional and 2DST echocardiography. RV fractional area change (RVFAC), tricuspid annular plane systolic excursion (TAPSE), E/A, E/e′ and 2DST parameters [global longitudinal peak systolic strain (GS) and strain rate (GSRs), global strain rate in early (GSRe) and late (GSRa) diastole] of 40 HLHS patients were compared at 1.6 and at 5.1 years after TCPC. RVFAC, E/A, E/e′ and GS did not change, whereas TAPSE (13.7 ± 3.2 vs. 10.5 ± 2.4 mm/m2, p < 0.001), GSRs (?1.56 ± 0.28 vs. ?1.35 ± 0.31 1/s, p < 0.001), GSRe (2.22 ± 0.49 vs. 1.96 ± 0.44 1/s, p = 0.004) and GSRa (1.19 ± 0.39 vs. 0.92 ± 0.39 1/s, p < 0.001) decreased significantly. Systolic and diastolic RV function parameters of HLHS patients decreased from 1.6 to 5.1 years after TCPC in our patients. Changes in global strain rate parameters may be signaling early RV dysfunction that is not detectable by traditional echocardiography. Further study is needed to verify this and to determine whether these changes are clinically relevant.  相似文献   
125.
Males and females exhibit several differences in brain structure and function. To examine the basis for these sex differences, we investigated the influences of sex hormones and sex chromosomes on brain structure and function in mice. We used the Four Core Genotype (4CG) mice, which can generate both male and female mice with XX or XY sex chromosome complement, allowing the decoupling of sex chromosomes from hormonal milieu. To examine whole brain structure, high-resolution ex vivo MRI was performed, and to assess differences in cognitive function, mice were trained on a radial arm maze. Voxel-wise and volumetric analyses of MRI data uncovered a striking independence of hormonal versus chromosomal influences in 30 sexually dimorphic brain regions. For example, the bed nucleus of the stria terminalis and the parieto-temporal lobe of the cerebral cortex displayed steroid-dependence while the cerebellar cortex, corpus callosum, and olfactory bulbs were influenced by sex chromosomes. Spatial learning and memory demonstrated strict hormone-dependency with no apparent influence of sex chromosomes. Understanding the influences of chromosomes and hormones on brain structure and function is important for understanding sex differences in brain structure and function, an endeavor that has eventual implications for understanding sex biases observed in the prevalence of psychiatric disorders.  相似文献   
126.
127.

Key points

  • Aerobic exercise, such as running, enhances adult hippocampal neurogenesis (AHN) in rodents.
  • Little is known about the effects of high‐intensity interval training (HIT) or of purely anaerobic resistance training on AHN.
  • Here, compared with a sedentary lifestyle, we report a very modest effect of HIT and no effect of resistance training on AHN in adult male rats.
  • We found the most AHN in rats that were selectively bred for an innately high response to aerobic exercise that also run voluntarily and increase maximal running capacity.
  • Our results confirm that sustained aerobic exercise is key in improving AHN.

Abstract

Aerobic exercise, such as running, has positive effects on brain structure and function, such as adult hippocampal neurogenesis (AHN) and learning. Whether high‐intensity interval training (HIT), referring to alternating short bouts of very intense anaerobic exercise with recovery periods, or anaerobic resistance training (RT) has similar effects on AHN is unclear. In addition, individual genetic variation in the overall response to physical exercise is likely to play a part in the effects of exercise on AHN but is less well studied. Recently, we developed polygenic rat models that gain differentially for running capacity in response to aerobic treadmill training. Here, we subjected these low‐response trainer (LRT) and high‐response trainer (HRT) adult male rats to various forms of physical exercise for 6–8 weeks and examined the effects on AHN. Compared with sedentary animals, the highest number of doublecortin‐positive hippocampal cells was observed in HRT rats that ran voluntarily on a running wheel, whereas HIT on the treadmill had a smaller, statistically non‐significant effect on AHN. Adult hippocampal neurogenesis was elevated in both LRT and HRT rats that underwent endurance training on a treadmill compared with those that performed RT by climbing a vertical ladder with weights, despite their significant gain in strength. Furthermore, RT had no effect on proliferation (Ki67), maturation (doublecortin) or survival (bromodeoxyuridine) of new adult‐born hippocampal neurons in adult male Sprague–Dawley rats. Our results suggest that physical exercise promotes AHN most effectively if the exercise is aerobic and sustained, especially when accompanied by a heightened genetic predisposition for response to physical exercise.

Abbreviations

AHN
adult hippocampal neurogenesis
BDNF
brain‐derived neurotrophic factor
BrdU
bromodeoxyuridine
HIT
high‐intensity interval training
HRT
high‐response trainer
LRT
low‐response trainer
RW
running wheel
Sed
sedentary
TBS
Tris‐buffered saline
V˙O2max
maximal oxygen uptake
  相似文献   
128.
Sir, A 14.5-year-old female received chemotherapy and concomitantlymonthly GnRH agonist injections (Decapeptyl CR 3.75 mg/month),and ‘miniMantle’ irradiation (2500 cGy) in1995 due to stage IV ALK positive anaplastic large cell lymphoma(Blumenfeld and Eckman, 2005). Several months later, she underwentautologous stem cell transplantation (SCT)  相似文献   
129.
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