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91.
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93.
Numerous operative and conservative treatments have been described in the published work for the management of sacrococcygeal pilonidal sinus; yet there remains considerable debate over its ideal treatment. This report is an audit of our results using the Karydakis flap repair in the management of this condition. We analysed prospective data on 70 patients who had had a Karydakis procedure. The length of follow up ranged from 1 to 79 months (median 36 months). Seventy-one operations were carried out in 70 patients. This included 12 patients (17%) who had previously undergone between one and four procedures (median 2) for recurrent disease. Superficial wound breakdown occurred in 27 patients (38%) and complete wound breakdown occurred in six patients (8.4%). These wounds were allowed to heal by secondary intent. The median time to complete healing for superficial and complete wound breakdown was 80 and 84 days, respectively. Disease recurrence occurred in three patients (4.2%) -- two of whom had recurrent disease at the time of this presentation. Of the three patients who had a recurrence after our surgery, two had a superficial breakdown and one had a complete wound breakdown. Sacrococcygeal pilonidal disease has a low recurrence rate when treated by the Karydakis operation involving flattening of the midline cleft. This procedure avoids the need for more complicated flap repairs.  相似文献   
94.
《Human immunology》2020,81(5):237-243
Th17 cells, known as a highly pro-inflammatory subtype of Th cells, are involved very early in numerous aspects of multiple sclerosis (MS) and experimental autoimmune encephalomyelitis (EAE) neuropathology. A crucial event for the formation and accumulation of MS lesions is represented by the disruption of the blood brain barrier (BBB) in relapsing-remitting MS. Th17 cells also contribute to the progression of MS/EAE. These events will allow for the passage of inflammatory cells into the brain. Secondary to this, increased recruitment of neutrophils occurs, followed by increased protease activity that will continue to attract macrophages and monocytes, leading to brain inflammation with sustained myelin and axon damage.This review focuses mainly on the role of Th17 cells in penetrating the BBB and on their important effects on BBB disruption via their main secretion products, IL-17 and IL-22. We present the morphological aspects of Th17 cells that allow for intercellular contacts with BBB endothelial cells and the functional/secretory particularities of Th17 cells that allow for intercellular communications that enhance Th17 entry into the CNS. The cytokines and chemokines involved in these processes are described. In conclusion, Th17 cells can efficiently cross the BBB using pathways distinct from those used by Th1 cells, leading to BBB disruption, the activation of other inflammatory cells and neurodegeneration in MS patients.  相似文献   
95.
This paper aims at investigating the electrical tree characteristics of isotactic polypropylene (iPP)/syndiotactic polypropylene (sPP) blends for thermoplastic cable insulation. PP blended samples with sPP contents of 0, 5, 15, 30, and 45 wt% are prepared, and electrical treeing experiments are implemented under alternating current (AC) voltage at 50, 70, and 90 °C. Experimental results show that with the incorporation of sPP increasing to 15 wt%, the inception time of electrical tree increases by 8.2%. The addition of sPP by 15% distinguishes an excellent performance in inhibiting electrical treeing, which benefits from the ability to promote the fractal dimension and lateral growth of branches. Further increase in sPP loading has a negative effect on the electrical treeing resistance of blended insulation. It is proved by DSC and POM that the addition of sPP promotes the heterogeneous crystallization the of PP matrix, resulting in an increasing density of interfacial regions between crystalline regions, which contains charge carrier traps. Charges injected from an electrode into a polymer are captured by deep traps at the interfacial regions, thus inhibiting the propagation of electrical tree. It is concluded that the modification of crystalline morphology by 15 wt% sPP addition has a great advantage in electrical treeing resistance for PP-based cable insulation.  相似文献   
96.
Lois Oppenheim has offered us a very complete analysis of Samuel Beckett's creative work. We shared with her his huge suffering, his craziness connected to his family history, and his incredible energy in writing. Beckett was a brilliant artist whose creations are frightening for most of us and at the same time make us very curious about witnessing the pain of human beings. I discuss two points in particular: Oppenheim's hypothesis that trauma was the cause of Samuel Beckett's troubles and the influence on his writing of his experience with psychoanalysis.  相似文献   
97.
Background This paper focuses on the transition to supported employment for people with intellectual disabilities paying particular attention to the impact of job breakdown on psychological well‐being; an issue often omitted from studies. Materials and Methods Forty‐nine people with intellectual disabilities were interviewed within 3 months of entering supported employment and 9–12 months later. Data collection involved in‐depth interviews with people with intellectual disabilities, their carers and employers and completion of a self‐report measure of depression and anxiety (an adapted form of the Hospital Anxiety and Depression Scale), and a self‐report measure of quality of life (the ComQol). Results By time of the follow‐up interviews, 13 of the 49 jobs had broken down. Analysis of scores measuring quality of life, anxiety and depression showed no effect for loss of employment. However, interviews with participants indicated that job loss had a considerable impact on those affected. Conclusions There were a wide range of reasons for job breakdown, many of which were particular to the circumstances of people with intellectual disabilities. Although job breakdown does not have an impact of anxiety or depression many participants found job loss traumatic.  相似文献   
98.
Electrical actuators made from films of dielectric elastomers coated on both sides with stretchable electrodes may potentially be applied in microrobotics, tactile and haptic interfaces, as well as in adaptive optical elements. Such actuators with compliant electrodes are sensitive to the pull-in electromechanical instability, limiting operational voltages and attainable deformations. Electrode-free actuators driven by sprayed-on electrical charges were first studied by Röntgen in 1880. They withstand much higher voltages and deformations and allow for electrically clamped (charge-controlled) thermodynamic states preventing electromechanical instabilities. The absence of electrodes allows for direct optical monitoring of the actuated elastomer, as well as for designing new 3D actuator configurations and adaptive optical elements.  相似文献   
99.
To clarify the involvement of calpains in sarcolemmal remodeling, we examined the expression of calpains and their substrate, alpha-fodrin, in various disorders of muscle. Although immunohistological reactions for alpha-fodrin and calpains were weak in normal control muscles, intense immunoreactivity for alpha-fodrin at the sarcolemma and for calpains throughout the cytoplasm were detected in small muscle fibers from patients with inflammatory myositis (IM), rhabdomyolysis (Rhab), and Duchenne muscular dystrophy (DMD). Most of the calpain-alpha-fodrin double-positive muscle fibers in IM and Rhab also expressed the developmental form of myosin heavy chain. The sarcolemma of these small muscle fibers reacted with an antibody that specifically recognizes the 150-kDa fragments of alpha-fodrin (SBDP 150s) cleaved by calpain, but not caspase 3. Western blot analysis confirmed these results. These observations indicate that calpain is activated and reacts with alpha-fodrin as a substrate at the sarcolemma, and plays a key role in modulating sarcolemmal proteins to adapt to the specific conditions in each myopathy.  相似文献   
100.
In the brain, alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA) receptors mediate glutamatergic neurotransmission and, when intensely activated, can induce excitotoxic cell death. In addition to their ionotropic properties, however, AMPA receptors have been functionally coupled to a variety of signal transduction events involving Src-family kinases, G-proteins, and the mitogen-activated protein kinase (MAPK). In the present study, we tested whether AMPA receptors are linked to appropriate signaling events in order to prevent neuronal injury and/or enhance recovery. AMPA stimulation in hippocampal slice cultures caused the selective activation of MAPK through the upstream activator MAPK kinase (MEK). Inhibition of either component of the AMPA receptor--MAPK pathway potentiated cellular damage due to serum deprivation, suggesting that this pathway facilitates compensatory signals in response to injury. Correspondingly, positive modulation of AMPA receptors with the Ampakine 1-(quinoxalin-6-ylcarbonyl)piperidine (CX516) enhanced MAPK activation and reduced the extent of synaptic and neuronal degeneration resulting from excitotoxic episodes. CX516 was neuroprotective when infused into slices either before or after the insult. The Ampakine derivative also elicited neuroprotection in an in vivo model of excitotoxicity as evidenced by reduction in lesion size and preservation of two different types of neurons. Interestingly, the AMPA receptor--MAPK pathway selectively protects against excitotoxicity since enhancing the pathway did not protect against the nonexcitotoxic, slow pathology initiated by lysosomal dysfunction. The results indicate that glutamatergic communication is important for cellular maintenance and that AMPA receptors activate survival signals to counterpoise their own excitotoxic potential.  相似文献   
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