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【摘要】 梅毒是由梅毒螺旋体进入循环系统进行血行播散导致的多系统损害,但目前其全身播散的具体机制尚未完全明确。基于国内外的研究进展,本文从梅毒螺旋体黏附与细胞外基质降解、细胞间连接和细胞骨架系统破坏、血管生成、炎症细胞浸润等多方面探讨梅毒螺旋体血行播散的机制,为进一步研究提供理论基础。 相似文献
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目的:比较急性缺血性卒中患者卒中后认知障碍的发生与软脑膜侧支循环的代偿程度及是否接受静脉溶栓治疗的相关性。方法:前瞻性收集2019年1月至2021年3月在石河子市人民医院住院的急性前循环脑梗死患者161例,获取患者入院时人口学资料,包括是否溶栓、性别、合并症等;通过蒙特利尔认知评估量表(Montreal cognitive assessment,MoCA)评分、简易精神状态检查量表(mini mental state examination,MMSE)评分评估患者认知功能;入院时美国国立卫生院卒中量表(National Institute of Health Stroke Scale,NIHSS)评分获取患者神经功能缺损症状;通过Blessed行为量表(Blessed behavior scale,BBS)评分评估患者的日常生活能力;通过区域软脑膜评分(regional leptomeningeal collateral score,rLMC)获取患者软脑膜侧支循环;根据卒中后6个月是否合并认知障碍分为认知障碍组和非认知障碍组,采用logistic多因素回归方法进行统计比较,分析2组患... 相似文献
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Yassir Turki Suha Saleh Shatha Albaik Yasmeen Barham Dorien van de Vrie Yousef Shahin Majed Hababeh Akihiro Seita 《Lancet》2019
Background
Mental health is a major public health priority, particularly among refugees worldwide. The United Nations Relief and Works Agency for Palestine Refugees (UNRWA) started to integrate mental health and psychosocial support (MHPSS) into its primary health-care services in Jordan in late 2017. This baseline study aimed to assess the knowledge, attitudes, practices, and perceived barriers among UNRWA health staff regarding the implementation of the MHPSS programme.Methods
The UNRWA Health Programme conducted a cross-sectional study of a sample of 220 out of the 390 male and female doctors, dentists, nurses, and midwives who work at 16 of the 25 UNRWA health centres in Jordan during November, 2017. Individuals on duty at the health centres on the day of the survey were included. The 16 health centres were selected based on their size and accessibility to surveyors (reflecting proximity to Amman, and the size of population served). Of the selected health centres, seven were large, seven were medium, and two were small according to the UNRWA classification of health centres (based on the number of medical doctors). A validated self-administered questionnaire was used. Ethics approval was granted by the UNRWA Health Programme ethics committee, and informed written consent was obtained from all participants. Data analysis was performed using SPSS (version 22).Findings
Of the participants, 73% (161 of 220) believed that their knowledge of MHPSS programmes was insufficient, with no significant difference (p=0·116) between different categories of staff. Furthermore, 88% (194 of 220) said that they needed more training, 67% (147 of 220) reported that the number of mental health cases is increasing, and 50% (110 of 220) that dealing with these cases is difficult. Reflecting on the past 12 months, 31% of staff (69 out of 220) reported meeting between one and ten children, and 45% (100 out of 220) reported meeting between one and ten adults suspected of having mental illnesses. The most suspected condition was depression (84%; 150 of 220), followed by epilepsy (64%; 140 of 220). The main perceived barriers to implementation included the limited availability of MHPSS policies (87%; 192 of 220), MH professionals (86%; 190 of 220), resources (86%; 189 out of 220), and lack of privacy (14%; 31 out of 220).Interpretation
Most health staff had positive attitudes towards MHPSS programme implementation but felt they lacked the required knowledge. There is a need for training and clear technical guidelines. Perceived barriers to MHPSS programme implementation need to be tackled with a structured plan of action.Funding
The UNRWA Health Programme, UNRWA Headquarters, Amman, Jordan. 相似文献6.
Hong Li Ting Ting Wu Pei Chang Liu Xue Song Liu Yan Mu Yang Song Guo Yuan Chen Li Ping Xiao Jiang Feng Huang 《The American journal of emergency medicine》2019,37(7):1301-1306
AimsThis retrospective study aims to analyze and explore the clinical characteristics, risk factors, and in-hospital outcomes - including return of spontaneous circulation (ROSC) and survival to discharge - of hospitalized patients admitted with acute coronary syndrome (ACS) suffering cardiac arrest.MethodsACS patients admitted to three tertiary hospitals in Fujian, China, were evaluated retrospectively from January 1, 2012 to December 30, 2016. Data were collected, based on the Utstein Style, for all cases of attempted resuscitation for IHCA. We analyzed patient characteristics, pre-event variables, event variables, and the main outcomes, including ROSC and survival to discharge, and identified the influencing factors on the outcomes.ResultsThe total number of ACS admissions across the three hospitals during this study period was 21,337. Among these admissions, 320 ACS patients experienced IHCA (incidence: 1.50%); 134 (41.9%) patients experienced ROSC; and 68 (21.2%) survived to discharge. The findings indicated that four factors were associated with ROSC, including age <70 years-old, shockable rhythm, duration of resuscitation (≤15 min and 16–30 min), and PCI. Five factors were associated with survival to discharge, including age <70 years-old, shockable rhythm, the duration of resuscitation (≤15 min and 16–30 min), Killip ≤ II, and CCI ≤ 2.ConclusionYounger age, shockable rhythm, and shorter duration of resuscitation were all factors demonstrated to be a predictor of ROSC and survival to hospital discharge. 相似文献
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Puerarin (PR), a natural isoflavone isolated from Chinese traditional plant pueraria lobata, has attracted considerable attention due to its important biological and pharmacological activities. However, its effects on lesion of peri-implant and related mechanism of action are still not clear, which require further investigation. In this study, we evaluated the effects of PR on polymethylmethacrylate (PMMA)-induced lesion of peri-implant in vitro and in vivo, and explored its possible mechanism of action. Our results indicated that PR could inhibit PMMA-induced osteoclastogenesis in RAW264.7 cells with a dose-dependent manner in vitro and effectively down-regulate mRNA and protein expressions of matrix metalloprotein 9 (MMP-9), tumor necrosis factor (TNF)-α, interleukin (IL)-6, and receptor activator of nuclear factor (NF)-κB (RANK), primarily via the suppression of NF-κB signaling. Furthermore, we found that PMMA induction could directly cause the phosphorylation of IκB and significantly promote the nuclear translocation of p65 in RAW264.7 cells. In other words, PR was able to dose-dependently attenuate the PMMA-induced nuclear translocation of p65 in RAW264.7 cells. In vivo, PR was observed to attenuate PMMA-induced osteoclastogenesis, osteolysis, mRNA expressions of receptor activator of nuclear factor (NF)-κB ligand (RANKL) and RANK, as well as protein levels of MMP-9, TNF-α, IL-6, and p65 in a murine calvarial osteolysis model. These findings suggested that PR might be a potential therapeutic drug to lesion of peri-implant, and provided new insights for understanding its possible mechanism. 相似文献
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Victoria A. Chang Dawn M. Meyer Brett C. Meyer 《Journal of stroke and cerebrovascular diseases》2019,28(1):163-166
Background
Acute stroke codes may be activated for anisocoria, but how often these codes lead to a final stroke diagnosis or alteplase treatment is unknown. The purpose of this study was to assess the frequency of anisocoria in stroke codes that ultimately resulted in alteplase administration.Methods
We retrospectively assessed consecutive alteplase-treated patients from a prospectively-collected stroke registry between February 2015 and July 2018. Based on the stroke code exam, patients were categorized as having isolated anisocoria [A+(only)], anisocoria with other findings [A+(other)], or no anisocoria [A?]. Baseline demographics, stroke severity, alteplase time metrics, and outcomes were also collected.Results
Ninety-six patients received alteplase during the study period. Of the 94 who met inclusion criteria, there were 0 cases of A+(only). There were 9 cases of A+(other) (9.6%). A+(other) exhibited higher baseline National Institutes of Health (NIH) Stroke Scale scores compared to A? (17 versus 7; P?=?.0003), and no additional differences in demographics or alteplase time metrics. Final stroke diagnosis and other outcome measures were no different between A+(other) and A?. Of the A+ patients without pre-existing anisocoria, 5 of 6 (83%) had posterior circulation events or diffuse subarachnoid hemorrhage.Conclusions
In this exploratory analysis, zero patients with isolated anisocoria received alteplase treatment. Anisocoria as a part of the neurologic presentation occurred in 10% of alteplase patients, and was strongly associated with a posterior circulation event. Therefore, we conclude that anisocoria has a higher likelihood of leading to alteplase treatment when identified in the presence of other neurologic deficits. 相似文献9.
Krystyna Dąbrowska 《Medicinal research reviews》2019,39(5):2000-2025
Bacteriophages are not forgotten viruses anymore: scientists and practitioners seek to understand phage pharmacokinetics in animals and humans, investigating bacteriophages as therapeutics, nanocarriers or microbiome components. This review provides a comprehensive overview of factors that determine phage circulation, penetration, and clearance, and that in consequence determine phage applicability for medicine. It makes use of experimental data collected by the phage community so far (PubMed 1924-2016, including non-English reports), combining elements of critical and systematic review. This study covers phage ability to enter a system by various routes of administration, how (and if) the phage may access various tissues and organs, and finally what mechanisms determine the courses of phage clearance. The systematic review method was applied to analyze (i) phage survival in the gut (gut transit) and (ii) phage ability to enter the mammalian system by many administration routes. Aspects that have not yet been covered by a sufficient number of reports for mathematical analysis, as well as mechanisms underlying trends, are discussed in the form of a critical review. In spite of the extraordinary diversity of bacteriophages and possible phage applications, the analysis revealed that phage morphology, phage specificity, phage dose, presence of sensitive bacteria or the characteristics of treated individuals (age, taxonomy) may affect phage bioavailability in animals and humans. However, once phages successfully enter the body, they reach most organs, including the central nervous system. Bacteriophages are cleared mainly by the immune system: innate immunity removes phages even when no specific response to bacteriophages has yet developed. 相似文献
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ObjectiveThe purpose of this paper is to review the efficacy and safety profile in children treated with topical 0.03% Tacrolimus ointment for vernal keratoconjunctivitis in Middle East and to propose a treatment posology. According to recent studies, a complex non-IgE dependent mechanism plays a relevant role in the pathogenesis of vernal keratoconjunctivitis. Numerous cells and mediators have been found in the serum, conjunctiva and tears of patients with Vernal keratoconjunctivitis.DesignThis case series included 10 patients from a single centre, pediatric department of a tertiary hospital with active symptomatic vernal keratoconjunctivitis. All the patients had proliferative lesions and corneal involvement despite conventional medications, including topical steroids. All other medications, systemic and topical: steroids, antihistamines and cyclosporine, were unsuccessful. Patients were treated with topical 0.03% Tacrolimus ointment twice daily for 8 weeks and then once a day for the next two month followed by thrice a week for two months. The changes in symptoms and signs after treatment were evaluated, also the development of possible complications was assessed.ResultsThe results showed a significant reduction in signs and symptoms after 4 weeks of the treatment. Clinical resolution of giant papillae and corneal lesions were seen within eight weeks and no additional drug was required during that period, except tear substitutes. Treatment was continued for period of two months and then slowly reduced.ConclusionThe use of 0.03% Tacrolimus ointment is safe and effective in children refractory to conventional treatment of vernal keratoconjunctivitis even in high temperature climate as Middle East. Due to the effectiveness of the treatment, the dosage used may be proposed for conventional use. 相似文献