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1.
Permissive herpes simplex virus (HSV) infection in tissue culture results in host cell destruction. Latent HSV infection in vivo occurs in neurons of peripheral sensory ganglia (PSG) and it therefore can not take place in neurons in which the virus has completed a lytic replication cycle similar to that present in vitro. Our hypothesis, based on experimental data and observations in humans, suggests that establishment of latent infection and reactivation of HSV-1 does not involve neuronal cell loss. Latency is established in neurons in which the virus does not replicate and is determined, in part, by the tissue levels of a herpes transactivating protein (Vmw65) that is a component of the viral tegument. We also suggest that reactivation of latent infection does not involve destruction of neurons and is due to replication of virus at the peripheral mucocutaneous tissues to where virus or viral DNA have been transported from the nervous tissue. Alternatively, reactivation is initiated in the PSG using a replication cycle which does not involve irreversible damage to neurons. This model explains the lack of damage to neurons which continue to serve as permanent reservoirs of latent virus for the entire life of the host.  相似文献   
2.
Background  Psoriasis is a chronic disease characterized by abnormal epidermal proliferation, inflammation and angiogenesis. It has been reported that vascular endothelial growth factor (VEGF) is overexpressed in lesional psoriatic skin and its serum levels are significantly elevated in patients with moderate to severe disease.
Objective  This study aims to evaluate the possible role of VEGF in the pathogenesis of psoriasis, and its significance as an indicator of disease severity and control.
Methods  Thirty patients with moderate to severe psoriasis and 10 healthy controls were subjected to baseline evaluation of VEGF. Patients were divided into three groups according to the received treatment: psoralen plus ultraviolet A (PUVA) thrice weekly (group 1), acitretin 50 mg daily (group 2), and combined PUVA twice weekly and acitretin 25 mg daily (group 3).Treatment continued for 16 weeks or up to clinical cure. Every patient was subjected to severity evaluation by Psoriasis Area and Severity Index (PASI) and measurement of serum VEGF before and after treatment.
Results  Mean serum levels of VEGF were significantly elevated in patients (327 ± 66.2 pg/mL) than control subjects (178 ± 83.4 pg/mL). A highly significant correlation was found between VEGF and PASI score, but not with other variables. The best clinical response, the least side-effects and the highest reduction of VEGF serum levels were achieved by the combined therapy.
Conclusion  The present study supported the proposed role of VEGF in the pathogenesis of psoriasis, and suggested that it could serve as a good indicator of disease severity and control.  相似文献   
3.
本文报告动脉粥样硬化(AS)形成和消退研究的部分工作。在复制AS形成和消退模型的基础上,研究了AS形成和消退中的内皮细胞、平滑肌细胞和单核细胞的改变。  相似文献   
4.
Abstract Human immunodeficiency virus (HIV)-l neuropathogenesis can be divided into three important components: (i) virus entry into the nervous system; (ii) the role of viral proteins and/or cellular products in neural tissue damage; and (iii) the mechanisms of neuronal injury/death. Both blood derived macrophages or trafficking HIV-1 infected T-lymphocytes have been implicated in viral entry to the central nervous system (CNS). The major cell type harboring productive HIV-1 infection in the nervous system is the perivascular macrophage/ microglia. The HIV-1 infection of brain astrocytes, restricted to the expression of regulatory gene products, may cause astrocyte dysfunction and contribute to neuronal injury or to disruption of the blood-brain barrier (BBB). Studies of cerebrospinal fluid and postmortem tissues reveal chronic inflammation/immune activation in the nervous system during the later stages of HIV-1 infection associated with disruption of BBB integrity. Blood-brain barrier damage may underlie the white matter pallor described in HIV-1 infection and could result in further entry into the CNS of toxic viral or cellular products, or additional HIV-1 infected cells. The HIV infected and activated macrophages/microglia produce excessive amounts of pro-inflammatory cytokines, including tumor necrosis factor alpha, and platelet activating factor. These products are directly toxic to human neurons in vitro. The HIV-1 envelope glycoprotein, gp 120 may stimulate the release of toxic factors from brain macrophages. Blocking N-methyl-D-aspartate (NMDA; or AMPA) glutamate receptors can antagonize candidate toxins of both viral and cellular origin. It has been postulated that (weak) excitotoxicity leads to oxidative stress in neurons and ultimately to apoptosis. Neuronal apoptosis occurs in the brains of both children and adults with HIV-1 infection. This understanding of HIV neuropathogenesis implies that therapeutic strategies should include: (i) anti-retroviral medications to decrease systemic and CNS virus load, and possibly to prevent perinatal transmission of HIV; (ii) anti-inflammatory compounds to decrease the chronic immune activation in microglia and allow the restoration of BBB integrity; and (iii) neuroprotective compounds to reduce neuronal injury and apoptotic death.  相似文献   
5.
跟痛症的发病机制与临床诊断方法   总被引:10,自引:0,他引:10  
跟痛症是一种临床常见多发疾病,以中老年患者居多,对于其发病机制与临床诊断鉴别方法不同的学者有着不同的见解。结合周福贻教授的理论与临床经验从发病机制、诊断、鉴别诊断及辅助检查等方面对跟痛症加以阐述。  相似文献   
6.
本文从髌骨软骨软化症的病因病理出发,阐述了活血化瘀疗法治疗髌骨软骨软化症的作用及其原理,列举了活血化瘀法在该病治疗中的具体运用,同时强调了在辨证施治基础上活血化瘀的重要性。  相似文献   
7.
Background: One hypothesis for the pathogenesis of keratoconus includes teenage allergy, ocular itch and associated eye‐rubbing. Methods: This study examined the prevalence of these factors for teenage and adult patients. The results for a sample of 53 subjects with bilateral keratoconus were compared with those for a control sample of non‐keratoconus subjects, who also routinely wore RGP contact lenses. The strongest dominant hand and the eye with more advanced keratoconus were also determined, to examine for a relationship between them. Results: The keratoconic sample reported significantly higher levels of allergy, itch and rubbing as teenagers and as adults. However, all distributions were bimodal, consistent with the hypothesis that allergy, itch and rubbing are relevant in the pathogenesis of keratoconus only when the highest levels of these factors are present. For example, a significant relationship between the stronger dominant hand and the more advanced eye was evident only in subjects who reported the most severe rubbing. Conclusions: This finding adds weight to the circumstantial evidence that rubbing contributes to the pathogenesis of keratoconus. Low levels of teenage rubbing by some keratoconic subjects suggest a non‐rubbing pathogenesis and that emphasis on rubbing management is not warranted in these cases. However, high levels of adult rubbing reported by many keratoconic subjects indicate that the standard advice to avoid vigorous and prolonged rubbing is often not effective, even when repeated. There appears to be an indication for the need to improve the management of eye‐rubbing for some patients with keratoconus or at risk of developing this disease.  相似文献   
8.
颈椎病手术中脊髓损伤的原因及处理   总被引:4,自引:0,他引:4  
目的探讨颈椎病术中脊髓损伤的原因及处理方法。方法我科2005年3月至2007年10月手术治疗279例颈椎病,对术中出现脊髓损伤的5例患者的临床资料进行回顾性分析。结果279例患者中5例发生脊髓损伤,发生率为1.79%。颈前路颈椎病手术中发生4例,后路单开门颈椎管扩大成形术中发生1例。经过清除血肿,甲基强的松龙等药物的及时治疗,5例患者逐渐恢复。结论颈椎病前、后路手术中均可能发生脊髓损伤,如能及时治疗,预后较好。  相似文献   
9.
Background: Reduction in salivary secretion is the hallmark of Sjögren's syndrome (SS). Calmodulin (CaM) and calmodulin binding proteins (CaMBPs) play a key role in the secretory process of saliva. Recent studies have suggested that SS‐B, an autoantibody associated with SS, is a CaMBP. This finding suggests that CaMBP may contribute to the loss of saliva in SS. To better understand the role(s) of these proteins in SS, the purpose of this study was to compare salivary CaMBPs in Sjögren's patients and controls. Methods: Saliva samples were collected from 20 patients and 20 age‐, race‐, and gender‐matched controls. CaM overlay was used to identify CaMBPs in saliva of patients and controls. Results: Higher number of salivary CaMBPs was observed among patients than controls. Conclusions: The increased number of salivary CaMBPs in SS may suggest a potential role for these proteins in the pathogenesis of the disease.  相似文献   
10.
卡氏肺孢子虫的超微结构观察   总被引:1,自引:0,他引:1  
采用皮下注射醋酸可的松和低蛋白饲养方法诱发SD大鼠自然感染卡氏肺孢子虫后,取其肺组织,按常规方法进行透射电镜的系统观察。结果除为Yoshida提出的卡氏肺孢子虫生活史的有性增殖和无性增殖循环的最新设想提供了某些形态学依据外,还继Vossen等之后再次发现该病原在1型肺泡上皮细胞内寄生的情况。本文最后就卡氏肺孢子虫对宿主的致病机理进行了讨论。  相似文献   
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