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31.
Plasticity enables alterations in transmission in nociceptive systems. It is this plasticity in the nervous system that can alter the linear relation between noxious stimuli and the perception of pain and is important in the switch from acute to chronic pain. In this way, a number of CNS mechanisms can alter neuronal activity, leading to abnormal ongoing and stimulus-evoked pains due to peripheral and central changes. Peripheral nerves can become sensitized, spinal cord neurons can be rendered hyperexcitable and ascending projections to higher centres can further trigger changes in descending controls from the midbrain and brainstem. Together, these changes, all of which appear to involve reversible physiological and pharmacological plasticity, can alter the relationship between an applied stimulus and the perceived response and so lead to persistent pain states.  相似文献   
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33.
Steroid hormones, especially glucocorticoids, androgens, and estrogens, have profound influence on immunity. Recent studies using cell-type specific steroid hormone receptor-deficient mice have revealed the precise roles of some of these hormones in the immune system. Glucocorticoids are known to have strong anti-inflammatory and immunosuppressive effects and pleiotropic effects on innate and adaptive immune responses. They suppress the production of inflammatory cytokines by macrophages and DCs and the production of IFN-γ by NK cells, thus inhibiting innate immunity. By contrast, glucocorticoids enhance the immune response by inducing the expression of IL-7R and CXCR4 in T cells and the accumulation of T cells in lymphoid organs in accordance with the diurnal change of the glucocorticoid concentration. Thus, glucocorticoids suppress innate immunity but enhance adaptive immunity. Androgens suppress the homeostasis and activation of ILC2s and the differentiation of Th2 and Th17 cells and enhance the suppressive function of Tregs, thereby alleviating allergic airway inflammation. Thus, these steroid hormones have pleiotropic functions in the immune system. Further investigations are awaited on the regulation of immunity and allergy by estrogens using cell-specific steroid hormone receptor-deficient mice.  相似文献   
34.
Immune defenses provide resistance against infectious disease that is critical to survival. But immune defenses are costly, and limited resources allocated to immunity are not available for other physiological or developmental processes. We propose a framework for explaining variation in patterns of investment in two important subsystems of anti-pathogen defense: innate (non-specific) and acquired (specific) immunity. The developmental costs of acquired immunity are high, but the costs of maintenance and activation are relatively low. Innate immunity imposes lower upfront developmental costs, but higher operating costs. Innate defenses are mobilized quickly and are effective against novel pathogens. Acquired responses are less effective against novel exposures, but more effective against secondary exposures due to immunological memory. Based on their distinct profiles of costs and effectiveness, we propose that the balance of investment in innate versus acquired immunity is variable, and that this balance is optimized in response to local ecological conditions early in development. Nutritional abundance, high pathogen exposure and low signals of extrinsic mortality risk during sensitive periods of immune development should all favor relatively higher levels of investment in acquired immunity. Undernutrition, low pathogen exposure, and high mortality risk should favor innate immune defenses. The hypothesis provides a framework for organizing prior empirical research on the impact of developmental environments on innate and acquired immunity, and suggests promising directions for future research in human ecological immunology.  相似文献   
35.
刘俊  华自森  李诚诚  许静 《陕西中医》2020,(12):1759-1762
目的:探讨补阳还五汤重用伸筋草治疗脑梗死后痉挛型偏瘫的作用。方法:收集脑梗死后痉挛型偏瘫患者共88例,分为两组,对照组44例,西医治疗加康复训练和补阳还五汤治疗; 研究组44例,西医治疗加康复训练及补阳还五汤重用伸筋草治疗。比较治疗前后患者患侧上下肢肌张力、临床疗效、NIHSS、日常生活能力Barthel指数以及上下肢运动功能和不良反应发生率。结果:治疗后,两组患者患侧上下肢肌张力≤1级者占比均升高,且研究组中≤1级者占比均高于对照组,组间比较有统计学意义(P<0.05)。两组临床疗效等级分布和总有效率比较,差异有统计学意义(P<0.05)。治疗后两组患者NIHSS评分均降低,且研究组NIHSS评分低于对照组,治疗后两组患者Barthel指数和患侧上下肢FMA评分均升高,且研究组均高于对照组,组间比较有统计学意义(P<0.05)。两组不良反应发生率比较,差异无统计学意义(P>0.05)。结论:补阳还五汤重用伸筋草能够显著降低患者患侧上下肢肌张力,改善临床疗效和神经功能缺损,提高患者日常生活能力和患侧运动功能,且安全性良好。  相似文献   
36.
ObjectiveTo evaluate the relationship between neural (re)organization of the somatosensory cortex and impairment of sensory function (2-point discrimination [2PD]) in individuals with unilateral cerebral palsy.MethodsWe included 21 individuals with unilateral cerebral palsy. 2PD thresholds were evaluated on thumb pads, and activation of the somatosensory cortex was recorded by functional MRI (fMRI) during passive movements of the affected hand. A lateralization index (LI) was calculated for the primary sensory (S1) and secondary sensory (S2) cortices and the correlation between the LI and 2PD thresholds was analysed.ResultsWe found a significant negative correlation between the 2PD thresholds and the S2 LI (r = −0.5, one-tailed P-value = 0.01) and a trend towards a negative correlation with the S1 LI (r = −0.4, one-tailed P-value = 0.05).ConclusionHigh levels of activation in the contralesional hemisphere were associated with high levels of sensory impairment in individuals with unilateral cerebral palsy. The interhemispheric (re)organization of the somatosensory system may not effectively compensate for somatosensory impairment.  相似文献   
37.
目的:观察肠炎清合剂对慢性复发型溃疡性结肠炎(UC)大肠湿热证患者诱导缓解效果及维持治疗对复发的影响,并从神经-内分泌-免疫炎症网络方面探讨了其作用机制。方法:将112例符合要求的患者随机分成对照组55例和观察组57例。对照组内服美沙拉嗪肠溶片,1.0 g/次,4次/d;Mayo评分系统≥7分者,加服醋酸泼尼松片,0.75 mg·kg^-1·d^-1;加用双歧杆菌活菌散剂,1包/次,2次/d,餐后温水冲服。观察组在对照组治疗的基础上服用肠炎清合剂,1包/次,分早晚2次服用。两组疗程均为连续治疗6周,再每周门诊复诊1次。进入缓解期后,两组患者均给予美沙拉嗪肠溶片,0.5 g/次,3次/d,维持治疗;观察组仍内服肠炎清合剂内服,至大肠湿热证评分减少≥90%以上。记录进入6周内缓解期的人数和缓解时间;进行治疗前后结肠镜检查,并进行Geboes指数和Baron法评价;进行治疗前后大肠湿热证评分和Mayo评分;检测治疗前后外周血白细胞介素-6(IL-6),IL-8,IL^-10,IL^-17,血管活性肠肽(VIP),胃动素(MTL)和神经肽Y(NPY);随访24周,记录复发情况。结果:经6周治疗后,观察组临床有效率为100%,黏膜愈合率为96.4%,均分别高于对照组的89.09%和81.82%(P<0.05),两组患者内镜应答率均为100%;经6周治疗后,观察组临床缓解率为91.23%,高于对照组的76.36%(χ2=4.581,P<0.05),观察组平均缓解时间短于对照组(P<0.01);治疗后观察组结肠黏膜评分,Geboes指数、大肠湿热证评分和Mayo评分均低于对照组(P<0.01);观察组患者外周血IL-6,IL-8和IL^-17水平均低于对照组(P<0.01),IL^-10水平高于对照组(P<0.01);观察组患者外周血VIP,MTL水平均低对照组(P<0.01),NPY水平高于对照组(P<0.01);观察组复发率为17.54%,低于对照组的38.18%(χ2=5.955,P<0.05);观察组平均复发时间长于对照组(P<0.01)。结论:在常规西医治疗的基础上,肠炎清合剂用于慢性复发型UC大肠湿热证的治疗,可诱导病情缓解,缩短病程,并能降低复发率,推迟复发时间,并对神经-内分泌-免疫炎症网络具有调节作用,从而可改善病情。  相似文献   
38.
Melanoma is a deadly tumor, which in recent years has been successfully treated with immune checkpoint inhibitors as PD-1/PD-L1 and CTLA-4 inhibitors and targeted therapy as BRAF and MEK inhibitors. However, immunotherapy poses deleterious side effects and pursuit of new therapeutic targets is warranted. As knowledge of tumor immunology advances, such targets are being recognized. C-motif chemokine receptor-5 (CCR5) is a receptor found on immune cells whose effects impact the immune response both to induce inflammation and to activate suppressor cells causing an anti-inflammatory effect. CCR5 is well known as a target for HIV therapy where its blockade is efficient and safe, it is also known that its mutation CCR5delta32 is for the most part non-pathological to its carriers. In oncology, activation of the CCR5 receptor has been observed in high-stage disease and CCR5 blockade has been associated with an increased immune response. In this letter, we build up the rationale to utilize CCR5 as a therapeutic target for metastatic melanoma.  相似文献   
39.
Purpose: Non-ambulatory persons with cerebral palsy are prone to low bone mineral density. In ambulatory persons with cerebral palsy, bone mineral density deficits are expected to be small or absent, but a consensus conclusion is lacking. In this systematic review bone mineral density in ambulatory persons with cerebral palsy (Gross Motor Function Classification Scales I–III) was studied.

Materials and methods: Medline, Embase, and Web of Science were searched. According to international guidelines, low bone mineral density was defined as Z-score?≤??2.0. In addition, we focused on Z-score?≤??1.0 because this may indicate a tendency towards low bone mineral density.

Results: We included 16 studies, comprising 465 patients aged 1–65?years. Moderate and conflicting evidence for low bone mineral density (Z-score?≤??2.0) was found for several body parts (total proximal femur, total body, distal femur, lumbar spine) in children with Gross Motor Function Classification Scales II and III. We found no evidence for low bone mineral density in children with Gross Motor Function Classification Scale I or adults, although there was a tendency towards low bone mineral density (Z-score?≤??1.0) for several body parts.

Conclusions: Although more high-quality research is needed, results indicate that deficits in bone mineral density are not restricted to non-ambulatory people with cerebral palsy.

  • Implications for Rehabilitation
  • Although more high-quality research is needed, including adults and fracture risk assessment, the current study indicates that deficits in bone mineral density are not restricted to non-ambulatory people with CP.

  • Health care professionals should be aware that optimal nutrition, supplements on indication, and an active lifestyle, preferably with weight-bearing activities, are important in ambulatory people with CP, also from a bone quality point-of-view.

  • If indicated, medication and fall prevention training should be prescribed.

  相似文献   
40.
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