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61.
Regular exercise has beneficial effects on cerebrovascular diseases; however, its biochemical mechanisms are not fully known. The purpose of this study was to determine antioxidant enzyme activities and lipid peroxidation of both hippocampi after applying exercise followed by occluding one common carotid. Wistar rats were divided into four groups of control, exercise, hypoperfusion and exercise–hypoperfusion (exe-hypo). In the exercise and exe-hypo groups, the rats were forced to run on a treadmill for 1 h a day for 2 months. The right common carotid of the animals in the (exe-hypo) group was occluded after the cessation of exercise. Surgery without occlusion of the carotid was applied on the control (without exercise) and exercise groups. All animals were sacrificed 1 and 24 h after surgery. The levels of malondialdehyde (MDA) and antioxidant enzyme activities in the hippocampi were measured. A significant interaction was observed between the exercise and hypoperfusion in both hippocampi (p < 0.05). In comparison with the control group, there was significant elevation of catalase activity in the right and left hippocampus of the hypo group at 24 h (p < 0.0001). Regarding the differences between the hemispheres, there was a significant increase in MDA and decrease in catalase activity in the left hippocampus in hypoperfusion group, but the exercise in the exe-hypo group succeeded in abolishing these alterations which were caused by hypoperfusion, This study shows that exercise pre-conditioning prevents some alterations in brain oxidant–antioxidant status which are induced by cerebral hypoperfusion. Further studies are needed in order to clarify the mechanism of exercise.  相似文献   
62.
Molecular Imaging and Biology - The early and accurate diagnosis of locoregional recurrence or metastasis in prostate cancer (PC) has a significant impact on treatment options. Prostatic-specific...  相似文献   
63.
The development of cost-effective, efficient, and novel catalytic systems is always an important topic for heterogeneous catalysis from academia and industrial points of view. Heteroatom-doped carbon materials have gained more and more attention as effective heterogeneous catalysts to replace metal-based catalysts, because of their excellent physicochemical properties, outstanding structure characteristics, environmental compatibility, low cost, inexhaustible resources, and low energy consumption. Doping of heteroatoms can tailor the properties of carbons for different utilizations of interest. In comparison to pure carbon catalysts, these catalysts demonstrate superior catalytic activity in many organic reactions. This review highlights the most recent progress in synthetic strategies to fabricate metal-free heteroatom-doped carbon catalysts including single and multiple heteroatom-doped carbons and the catalytic applications of these fascinating materials in various organic transformations such as oxidation, hydrogenation, hydrochlorination, dehydrogenation, etc.

Recent advances in metal-free heteroatom-doped carbon heterogeneous catalysts including the preparation methods and their catalytic applications in various organic reactions have been reported.  相似文献   
64.
The Pauson–Khand reaction (PKR) is a formal [2 + 2 + 1] cycloaddition involving an alkyne, an alkene and carbon monoxide mediated by a hexacarbonyldicobaltalkyne complex to yield cyclopentenones in a single step. This versatile reaction has become a method of choice for the synthesis of cyclopentenone and its derivatives since its discovery in the early seventies. The aim of this review is to point out the applications of PKR in the total synthesis of terpenes.

The Pauson–Khand reaction (PKR) is a formal [2 + 2 + 1] cycloaddition involving an alkyne, an alkene and carbon monoxide mediated by a hexacarbonyldicobaltalkyne complex to yield cyclopentenones in a single step.  相似文献   
65.
66.
Small fiber neuropathy (SFN) is being recognized with increasing frequency in neuromuscular practice due to improved diagnostic techniques. Although there are some common etiologies, up to one-third of cases are considered idiopathic. In recent years, several disorders have unexpectedly been reported in association with SFN, on clinical grounds and complementary investigations, including quantitative sensory testing, intraepidermal nerve fiber density and confocal corneal microscopy. Knowledge of these disorders is important in clinical practice as increased awareness enables prompt diagnosis of SFN in these settings and early optimal therapeutic management of affected patients. Furthermore, these new developments may lead to a better understanding of the pathophysiologic mechanisms underlying SFN in these different disorders as well as, in some cases, an expanded spectrum of affected organs and systems. This article reviews these reported associations, their possible pathophysiologic bases, and the potential resulting management implications.  相似文献   
67.
Coronavirus disease 2019 has created unprecedented challenges for amyotrophic lateral sclerosis (ALS) clinical care and research in the United States. Traditional evaluations for making an ALS diagnosis, measuring progression, and planning interventions rely on in-person visits that may now be unsafe or impossible. Evidence- and experience-based treatment options, such as multidisciplinary team care, feeding tubes, wheelchairs, home health, and hospice, have become more difficult to obtain and in some places are unavailable. In addition, the pandemic has impacted ALS clinical trials by impairing the ability to obtain measurements for trial eligibility, to monitor safety and efficacy outcomes, and to dispense study drug, as these also often rely on in-person visits. We review opportunities for overcoming some of these challenges through telemedicine and novel measurements. These can reoptimize ALS care and research in the current setting and during future events that may limit travel and face-to-face interactions.  相似文献   
68.
The effects of norepinephrine microinjected into the anterior hypothalamus were examined in feline affective defense behavior elicited by electrical stimulation of the region of the ventromedial nucleus. Anterior hypothalamic sites from which affective defense behavior could also be elicited by electrical stimulation and which are known to receive inputs from both the ventromedial nucleus and brainstem noradrenergic neurons were selected for pharmacological analysis. Intracerebral injections of 250 ng (1 nM) and 500 ng (2 nM) quantities of norepinephrine placed into the anterior hypothalamus resulted in a significant lowering of the attack thresholds. These reductions in response thresholds which were reversed by either pre- or post-treatment with yohimbine, indicate that the noradrenergic system may play an important role in the regulation of affective defense behavior.  相似文献   
69.
Aim  Several health problems have been reported to be triggered or facilitated by prolonged mask usage during the coronavirus disease 2019 (COVID-19) pandemic. While wearing a face mask, people tend to push their jaws forward and downward in a repetitive manner to hold their masks in the right position; these jaw motions may induce temporomandibular joint disorder (TMD). In this study, we aimed to investigate these repetitive jaw movements while wearing face masks and their effects on TMD. Patients and Methods  Patients who applied with TMD signs between June 2020 and May 2021 were evaluated prospectively. A survey using a questionnaire was conducted to define patients with TMD that caused only by mask-related repetitive jaw movements. Demographic data (age and gender), mean duration of daily mask usage, mask type, and magnetic resonance imaging results were recorded. Results  Prolonged daily mask usage (≥8 hours/day) was significantly higher in patients with mask-related habits (group a) with a rate of 40.4% ( p ≈ 0.001). Also, in this group, the disc displacement with reduction rate (54.6%) was higher compared with other groups ( p ≈ 0.010). On the contrary, patients with no underlying risk factor (group c) showed an unexpected high osteoarthritis rate ( p ≈ 0.029). Conclusions  In this study, we demonstrate that correcting the position of a face mask by repetitive jaw movements can increase the occurrence of TMD. Informing individuals wearing face masks about the risk of TMD and the importance of choosing the appropriate mask size according to the face shape are important issues to be addressed in the near future.  相似文献   
70.
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