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Cognitive Computation - The dangerously contagious virus named “COVID-19” has struck the world strong and has locked down billions of people in their homes to stop the further spread....  相似文献   
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Objectives:To assess cerebral venous thrombosis risk factors, and associated clinical outcomes in Jazan region, Kingdom of Saudi Arabia.Methods:This study is a retrospective review of the medical records of patients diagnosed with cerebral venous thrombosis and admitted to King Fahad Central Hospital in Jazan between 2010 and 2019. Data concerning socio-demographics, clinical features, risk factors, laboratory, and imaging investigations were retrieved. Furthermore, data about cases management, and outcomes, including death, were collected and analysed.Results:A total of 51 medical records were identified. The majority of the patients were females (68.6%), and the mean age of the patients was 33.3 years, of which three patients were under 18 years old. The most frequently recorded symptom was headache (76.5%), followed by seizure (45.1%). The most commonly recorded risk factor was protein S deficiency (57%), followed by anaemia (51%). Venous infarction and haemorrhage were the most common acute complications (13.7%). The majority of the patients had a favourable prognosis where only 27.5% recovered with disability and only one patient died due to the disease.Conclusion:Clinical presentation of cerebral venous thrombosis in Jazan region is similar to other local and international studies. However, anaemia was recorded as a main risk factor for the disease, which might require further investigation to assess the possible association between prevalence of anaemia in Jazan region and the incidence of cerebral venous thrombosis.

Cerebral venous thrombosis (CVT) is a rare form of cerebrovascular disease in comparison with arterial stroke. CVT cases represent approximately 0.5-1% of all types of stroke which mainly occur in young and middle-aged adults.1 The data concerning the global epidemiology of CVT is currently limited.2 However, the incidence of CVT has been reported to vary between countries where the incidence might be higher as in Asian and the Middle Eastern countries in comparison to Australia and European countries.3According to a recent study conducted in Australia, the incidence of CVT was reported to reach 15.7 per 1,000,000 persons on a yearly basis. The incidence was higher among women and among those between 31-50 years old.4 In the Middle East, an Iranian study looked at the frequency of CVT between 2001 and 2004, and the annual frequency of CVT was 12.3 per one million.5 An older study, conducted in the city of Riyadh in Saudi Arabia between 1985 and 1994, identified 40 cases of CVT. Those identified were aged between 16 and 40.6 In addition, in a more recent study conducted in Jeddah and Al-Baha between 1990 and 2010, the number of detected cases of CVT was 111 where 19 of these were detected among children.7The CVT occurs when a thrombus develops as a result of a disturbance of the balance between the process of prothrombosis and thrombolysis.8,9 Risk factors for CVT can be categorised into transient and permanent risk factors. Permanent risk factors are hereditary thrombophilia, systemic diseases or miscellaneous factors, such as obesity. Transient risk factors can be subcategorised into sex-specific, iatrogenic, or miscellaneous risk factors, such as infection, head trauma or anaemia.8 The prevalence of CVT risk factors differs between countries. Infection, pregnancy, post-partum period, and dehydration have been reported to be more common in Asia and the Middle Eastern countries in comparison to European countries.8Patients with CVT exhibit variable clinical manifestations and complications, some of which can be life threatening. The most common clinical presentation is a headache, while some patients exhibit other signs and symptoms, such as seizure, decreased level of consciousness, vomiting, focal neurological deficit, or visual symptoms.8-10 Venous infarction and haemorrhage are frequently reported complications of CVT.11 Late presentation of CVT patients can increase the risk of disability and death. The mortality rate among CVT patients has been reported to vary between 4.3% and 6.8%.12Since CVT risk factors and vulnerable groups can vary between different populations, assessment of the distribution of risk factors among local populations can be clinically valuable. Studies assessing CVT prevalence and associated risk factors and clinical outcomes in Saudi populations are currently limited. Furthermore, data about CVT in Jazan region is currently lacking. This investigation aims to identify cases diagnosed with CVT in Jazan region and to evaluate the risk factors and associated clinical outcomes.  相似文献   
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This paper propose a universal normalized vegetation index (UNVI), which is an improved vegetation index (VI) based on the universal pattern decomposition method (UPDM), termed VIUPD. We also derive new matrices to facilitate convenient calculation of the UNVI based on data from the MODIS and Landsat-TM, ETM, OLI satellite sensors. We compared the performance of the UNVI to the normalized difference vegetation index (NDVI), enhanced vegetation index (EVI) and modified soil adjusted vegetation index 2 (MSAVI2) to estimate the vegetation dynamics (chlorophyll content and leaf area index [LAI]). The results show that the UNVI was more sensitive to vegetation dynamics than the NDVI, EVI and MSAVI2. The UNVI has a higher LAI saturation point than the other three indices. The UNVI can be used to monitor global changes in above ground biomass (AGB) and gross primary production (GPP) with respect to a wide range of vegetation dynamics.  相似文献   
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Clinical and Experimental Medicine - Angiogenesis is a major prerequisite for hepatocellular carcinoma (HCC) development and progression. The present study aims to assess the potential role of two...  相似文献   
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Objective and methods: This paper reviews sources of data typically used in guideline development, available grading systems, their pros and cons, and the methods for evaluating risks of bias in publications, and proposes a revised method for grading evidence and recommendations for use in development of clinical treatment guidelines.

Results: The new World Federation of Societies of Biological Psychiatry (WFSBP) grading system allows guideline developers to follow a multi-step approach of defining levels of evidence, applying criteria for grading (define the acceptability) and the grading of recommendations.

Conclusions: Further, these updated WFSBP recommendations for rating evidence and treatment recommendations provide a grading system that takes into account potential biases in sources of evidence in arriving at final ratings that are likely more clinically meaningful and pragmatic and thus should be used for the development of future treatment guidelines.  相似文献   

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Objective

The aim of this study was to determine the alterations of walking energy expenditure and plantar pressure distribution in young adults with patellofemoral pain syndrome (PFPS).

Methods

Thirty five individuals (mean age: 21.31 ± 1.76) with PFPS constituted the patient group and forty healthy participants (mean age: 21.40 ± 2.11) the control group. Preferred walking speeds (PWS) were determined on the over ground. Individuals walked on a treadmill for 7 min at their PWS and 30% above PWS and oxygen consumption was recorded via a metabolic analyzer. Net oxygen consumption was calculated for each walking trial. Borg scale was applied to assess perceived exertion during walking trial. Plantar pressure distributions were measured by a pedobarography device. Plantar area was subdivided into six zones to evaluate the dynamic plantar pressure data.

Results

The mean PWS of PFPS and control groups were 4.69 ± 0.51 and 4.52 ± 0.60 km/h, respectively (p > .09). No significant difference was observed in energy expenditure during walking at PWS between 2 groups while oxygen consumption during 30% above PWS was higher in patient group (18.72 ± 3.75 and 16.64 ± 3.27) (p = .007). Net oxygen consumption was also found to be higher in PFPS group (15.12 ± 3.62 and 13.04 ± 3.24) (p = .005). The mean Borg scores were significantly higher in PFPS group at each walking trials (p < .001). No statistically significant difference was found between weight distribution (%) of symptomatic and nonsymptomatic extremity (50.45 ± 3.92% and 49.56 ± 3.93%, respectively) (p = .509). Dynamic pedobarography parameters were not different between 2 groups, and also between symptomatic and nonsymptomatic extremities (p > .05).

Conclusion

Although, rate of perceived exertion and energy expenditure during walking at 30% above PWS are affected negatively in young adults with PFPS, we may speculate that energy consumption and plantar pressure distribution can be compensated by a physiologic adaptation mechanism during walking at PWS.

Level of evidence

Level III, Therapeutic Study.  相似文献   
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