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11.
目的:研究未经正畸治疗的前牙有牙根吸收和无牙根吸收的错[牙合]患者的[牙合]及功能[牙合]特征,揭示引起牙根吸收的可能的[牙合]及咬合因素,为正畸治疗治疗前已有牙根吸收的患者提供可能的[牙合]及功能[牙合]参照标准。方法:用曲面断层片作为筛查方法,并用根尖片进一步确诊根尖吸收,对07年7月至08年3月在我正畸科初诊的患者进行调查,从中选择14名前牙根尖吸收为Ⅱ~Ⅲ度的错[牙合]畸形患者作为研究组,用年龄和性别作为控制标准随机选择14名无根尖吸收的错[牙合]畸形患者作为对照组,采用临床检查、模型分析和DenarMarkⅡ[牙合]架分析的方法研究两组的[牙合]和功能[牙合]特征,用spss14.0进行t检验统计分析。结果:两组的[牙合]特征不存在差异,临床检查和[牙合]架分析的结果均显示前牙牙根吸收组在侧方运动中前牙和后牙出现[牙合]干扰的数量高于对照组,其中[牙合]架分析发现牙根吸收患者在侧方运动中前牙出现[牙合]干扰的数量显著高于对照组(P〈0.05)。结论:未经治疗的错[牙合]畸形患者在侧方运动过程中前牙[牙合]干扰是发生前牙牙根吸收者可能原因。  相似文献   
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AIMS: To report the natural history of autochthonous hepatitis E and hepatitis E virus (HEV) IgG seroprevalence in Southwest England. METHODS: Patients with unexplained hepatitis were tested for hepatitis E and cases followed until recovery or death. Five hundred blood donors, 336 individuals over the age of 60 years and 126 patients with chronic liver disease were tested for HEV IgG. RESULTS: Forty cases of autochthonous hepatitis E (genotype 3) were identified. Hepatitis E was anicteric in 25% of cases and usually caused a self-limiting hepatitis predominantly in elderly Caucasian males. Six of 40 had a significant complication and three patients died, two of who had previously undiagnosed cirrhosis. Hepatitis E shows a seasonal variation with peaks in the spring and summer and no cases in November and December. HEV IgG prevalence increases with age, is more common in men and is 16% in blood donors, 13% in patients with chronic liver disease and 25% in individuals over 60 years. CONCLUSION: Autochthonous hepatitis E is more common than previously recognized, and should be considered in the differential diagnosis in patients with hepatitis, whatever their age or travel history. It carries a significant morbidity and when seen in the context of chronic liver disease carries an adverse prognosis.  相似文献   
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Introduction:Corona virus disease-2019 (COVID-19) presents primarily with respiratory symptoms. However, extra respiratory manifestations are being frequently recognized including gastrointestinal involvement. The most common gastrointestinal symptoms are nausea, vomiting, diarrhoea and abdominal pain. Gastrointestinal perforation in association with COVID-19 is rarely reported in the literature.Patient concerns and diagnosis:In this series, we are reporting 3 cases with different presentations of gastrointestinal perforation in the setting of COVID-19. Two patients were admitted with critical COVID-19 pneumonia, both required intensive care, intubation and mechanical ventilation. The first one was an elderly gentleman who had difficult weaning from mechanical ventilation and required tracheostomy. During his stay in intensive care unit, he developed Candidemia without clear source. After transfer to the ward, he developed lower gastrointestinal bleeding and found by imaging to have sealed perforated cecal mass with radiological signs of peritonitis. The second one was an obese young gentleman who was found incidentally to have air under diaphragm. Computed tomography showed severe pneumoperitoneum with cecal and gastric wall perforation. The third case was an elderly gentleman who presented with severe COVID-19 pneumonia along with symptoms and signs of acute abdomen who was confirmed by imaging to have sigmoid diverticulitis with perforation and abscess collection.Interventions:The first 2 cases were treated conservatively. The third one was treated surgically.Outcome:Our cases had a variable hospital course but fortunately all were discharged in a good clinical condition.Conclusion:Our aim from this series is to highlight this fatal complication to clinicians in order to enrich our understanding of this pandemic and as a result improve patients’ outcome.  相似文献   
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The putative tumour suppressor gene gravin is down-regulated in several solid tumours and is implicated in tumorigenesis. We have evaluated the expression levels of the gravin gene in the CD34(+)/blast cells of a range of myeloid malignancies as compared with controls using real-time quantitative polymerase chain reaction (PCR). Gravin was markedly down-regulated in 41 of 41 patients with acute myeloid leukaemia (AML), nine of 10 patients with myelodysplastic syndromes (MDS) and 33 of 33 patients with chronic myeloid leukaemia (CML), of whom 24 were in blast crisis (BC). We have shown that gravin is consistently down-regulated in the CD34(+)/blast cells of myeloid malignancies and may play a role in the molecular pathogenesis of these disorders.  相似文献   
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Introduction: Idiopathic systemic capillary leak syndrome (SCLS) is a unique disorder characterized by episodes of massive systemic leak of intravascular fluid leading to volume depletion and shock. A typical attack of SCLS consists of prodromal, leak and post-leak phases. Complications, such as compartment syndrome and pulmonary edema, usually develop during the leak and post-leak phases respectively. Judicious intravenous hydration and early use of vasopressors is the cornerstone of management in such cases.

Areas covered: The purpose of the present review is to provide an up-to-date, evidence-based review of our understanding of SCLS and its management in the light of currently available evidence.

Commentary: Idiopathic SCLS was first described in 1960 and, since then, more than 250 cases have been reported. A large number of cases have been reported over the past one decade, most likely due to improved recognition. In the acute care setting, most patients with SCLS are managed as per the Surviving Sepsis guidelines and receive aggressive volume resuscitation – which is not the optimal management strategy for such patients. There is a need to raise awareness amongst physicians and clinicians in order to improve recognition of this disorder and ensure its appropriate management.  相似文献   

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Apart from its classical function in bone and calcium metabolism, vitamin D is also involved in immune regulation and has been linked to various cancers, immune disorders and allergic diseases. Within the innate and adaptive immune systems, the vitamin D receptor and enzymes in monocytes, dendritic cells, epithelial cells, T lymphocytes and B lymphocytes mediate the immune modulatory actions of vitamin D. Vitamin D insufficiency/deficiency early in life has been identified as one of the risk factors for food allergy. Several studies have observed an association between increasing latitude and food allergy prevalence, plausibly linked to lower ultraviolet radiation (UVR) exposure and vitamin D synthesis in the skin. Along with mounting epidemiological evidence of a link between vitamin D status and food allergy, mice and human studies have shed light on the modulatory properties of vitamin D on the innate and adaptive immune systems. This review will summarize the literature on the metabolism and immune modulatory properties of vitamin D, with particular reference to food allergy.  相似文献   
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While Pakistan has made progress toward achieving Millennium Development Goal 5 for maternal health, it is unlikely to achieve the target; further, it is also not on track for Millennium Development Goal 4 regarding child health. Two low-cost, temperature stable and life-saving drugs, misoprostol and chlorhexidine, can respectively avert maternal and newborn deaths, and are particularly pertinent for poor and marginalized areas which bear the brunt of maternal and newborn deaths in Pakistan. In response, Mercy Corps led focused advocacy efforts to promote changes in policies, protocols, and regulatory environments for misoprostol (2012–2014) and for chlorhexidine (2014). These short-duration advocacy projects facilitated significant policy gains, such as inclusion of misoprostol and chlorhexidine into province-specific essential drug lists, development and endorsement of clinical protocols for the two drugs by provincial health departments, inclusion of misoprostol into pre-service training curriculum for several health cadres, and application for registration of chlorhexidine (at the concentration required for newborn care) by two pharmaceutical companies. These results were achieved by a consultative and evidence-based process which generated feedback from community members, program implementers, and policymakers, and ultimately put the government in the driver’s seat to facilitate change. Community Action Dialogue forums were linked with provincial-level Technical Working Groups and Provincial Steering Committees, who passed on endorsed recommendations to the Health Secretary. The key factors which facilitated change were the identification of champions within the provincial health departments, prioritization of relationship building and follow-up, focus on concrete advocacy aims rather than broad objectives, and the use of multi-stakeholder forums to secure an enabling environment for the policy changes to take root. While these advocacy initiatives resulted in significant policy changes in Pakistan’s devolved health system, to ensure these policy changes have an impact on health outcomes, Pakistan should focus on the scale-up of appropriate use of chlorhexidine and misoprostol. Further, future policy initiatives in Pakistan should make use of similar multi-stakeholder policy forums, while ensuring a third party to facilitate the process so that civil society and community voices are not lost in the policy development discussion.  相似文献   
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