Approximately 20% of patients with acute pancreatitis develop a severe disease associated with complications and high risk of mortality. The purpose of this study is to review pathogenesis and prognostic factors of se...Approximately 20% of patients with acute pancreatitis develop a severe disease associated with complications and high risk of mortality. The purpose of this study is to review pathogenesis and prognostic factors of severe acute pancreatitis (SAP). An extensive medline search was undertaken with focusing on pathogenesis, complications and prognostic evaluation of SAP. Cytokines and other inflammatory markers play a major role in the pathogenesis and course of SAP and can be used as prognostic markers in its early phase. Other markers such as simple prognostic scores have been found to be as e^ective as multifactorial scoring systems (MFSS) at 48 h with the advantage of simplicity, efficacy, low cost, accuracy and early prediction of SAP. Recently, several laboratory markers including hematocrit, blood urea nitrogen (BUN), creatinine, matrix metalloproteinase-9 (MMP-9) and serum amyloid A (SAA) have been used as early predictors of severity within the first 24 h. The last few years have witnessed a tremendous progress in understanding the pathogenesis and predicting the outcome of SAP. In this review we classified the prognostic markers into predictors of severity, pancreatic necrosis (PN), infected PN (IPN) and mortality.展开更多
为实现在自然环境条件下对苦瓜叶部病害的目标检测,该研究提出了一种基于改进的更快速区域卷积神经网络(Faster Region with Convolutional Neural Network Features,Faster R-CNN)的苦瓜叶部病害目标检测方法。Faster R-CNN以残差结构...为实现在自然环境条件下对苦瓜叶部病害的目标检测,该研究提出了一种基于改进的更快速区域卷积神经网络(Faster Region with Convolutional Neural Network Features,Faster R-CNN)的苦瓜叶部病害目标检测方法。Faster R-CNN以残差结构卷积神经网络ResNet-50作为该次试验的特征提取网络,将其所得特征图输入到区域建议网络提取区域建议框,并且结合苦瓜叶部病害尺寸小的特点,对原始的Faster R-CNN进行修改,增加区域建议框的尺寸个数,并在ResNet-50的基础下融入了特征金字塔网络(Feature Pyramid Networks,FPN)。结果表明,该方法训练所得的深度学习网络模型具有良好的鲁棒性,平均精度均值(Mean Average Precision,MAP)值为78.85%;融入特征金字塔网络后,所得模型的平均精度均值为86.39%,提高了7.54%,苦瓜健康叶片、白粉病、灰斑病、蔓枯病、斑点病的平均精确率(Average Precision,AP)分别为89.24%、81.48%、83.31%、88.62%和89.28%,在灰斑病检测精度上比之前可提高了16.56%,每幅图像的检测时间达0.322 s,保证检测的实时性。该方法对复杂的自然环境下的苦瓜叶部病害检测具有较好的鲁棒性和较高的精度,对瓜果类疾病预防有重要的研究意义。展开更多
Two wetland maps for the entire China have been produced based on Landsat data acquired around 1990 and 2000. Wetlands in China have been divided into 3 broad categories with 15 sub-categories except rice fields. In 1...Two wetland maps for the entire China have been produced based on Landsat data acquired around 1990 and 2000. Wetlands in China have been divided into 3 broad categories with 15 sub-categories except rice fields. In 1990, the total wetland area in China was 355208 km2 whereas in 2000 it dropped to 304849 km2 with a net loss of 50360 km2. During an approximate 10-year period, inland wetland reduced from 318326 to 257922 km2, coastal wetland dropped from 14335 to 12015 km2, while artificial wetland increased from 22546 to 34911 km2. The greatest natural wetland loss occurred in Heilongjiang, Inner Mon- golia, and Jilin with a total loss of over 57000 km2 of wetland. In western China, over 13000 km2 of wetlands were newly formed in Xinjiang, Tibet, and Qinghai. About 12000 km2 of artificial wetlands were also added for fish farm and reservoir constructions. The newly formed wetlands in western China were caused primarily by climate warming over that region whereas the newly created artificial wetlands were caused by economic developments. China’s wetland loss is caused mainly by human activities.展开更多
INTRODUCTIONOnly the liver has the great capability ofregeneration in mammal.Few hepatocytes are inthe phase of division in the normal liver of an adultmammal (including human beings),but theremaining hepatocytes can ...INTRODUCTIONOnly the liver has the great capability ofregeneration in mammal.Few hepatocytes are inthe phase of division in the normal liver of an adultmammal (including human beings),but theremaining hepatocytes can be induced to proliferatequickly by partial hepatectomy (PH),and,to somedegree,they stop dividing and re-differentiate intocells functioning as hepatocytes.This shows展开更多
BACKGROUND: Four different sizes (4, 5, 8 and 10 cm in diameter) can be found in the literature to categorize a liver hemangioma as giant. The present review aims to clarify the appropriateness of the size category...BACKGROUND: Four different sizes (4, 5, 8 and 10 cm in diameter) can be found in the literature to categorize a liver hemangioma as giant. The present review aims to clarify the appropriateness of the size category "giant" for liver heman- gioma. DATA SOURCES: We reviewed the reports on the categoriza- tion of hemangioma published between 1970 and 2014. The number of hemangiomas, size criteria, mean and range of hemangioma sizes, and number of asymptomatic and symp- tomatic patients were investigated in patients aged over 18 years. Liver hemangiomas were divided into four groups: 〈5.0 cm, 5.0-9.9 cm, 10.0-14.9 cm and 〉15.0 cm in diameter. Inclu- sion criteria were noted in 34 articles involving 1972 (43.0%) hemangiomas (〉4.0 cm). RESULTS: The patients were divided into the following groups: 154 patients (30.0%) with hemangiomas less than 5.0 cm in diameter (small), 182 (35.5%) between 5.0 cm and 9.9 cm (large), 75 (14.6%) between 10.0 and 14.9 cm (giant), and 102 (19.9%) more than 15.0 cm (enormous). There were 786 (39.9%) asymptomatic patients and 791 (40.1%) symptomatic patients. Indications for surgery related to symptoms were reported in only 75 (3.8%) patients. Operations including 137 non-anatomical resection (12.9%) and 469 enudeation (44.1%) were undearly related to size and symptoms.CONCLUSIONS: The term "giant" seems to be justified for liver hemangiomas with a diameter of 10 cm. Hemangiomas categorized as "giant" are not indicated for surgery. Surgery should be performed only when other symptoms are apparent.展开更多
Bartter and Gitelman syndromes(BS and GS) are inherited disorders resulting in defects in renal tubularhandling of sodium,potassium and chloride.Previously considered as genotypic and phenotypic heterogeneous diseases...Bartter and Gitelman syndromes(BS and GS) are inherited disorders resulting in defects in renal tubularhandling of sodium,potassium and chloride.Previously considered as genotypic and phenotypic heterogeneous diseases,recent evidence suggests that they constitute a spectrum of disease caused by different genetic mutations with the molecular defects of chloride reabsorption originating at different sites of the nephron in each condition.Although they share some characteristic metabolic abnormalities such as hypokalemia,metabolic alkalosis,hyperplasia of the juxtaglomerular apparatus with hyperreninemia,hyperaldosteronism,the clinical and laboratory manifestations may not always allow distinction between them.Diuretics tests,measuring the changes in urinary fractional excretion of chloride from baseline after administration of either hydrochlorothiazide or furosemide show very little change(< 2.3%) in the fractional excretion of chloride from baseline in GS when compared with BS,except when BS is associated with KCNJ1 mutations where a good response to both diuretics exists.The diuretic test is not recommended for infants or young children with suspected BS because of a higher risk of volume depletion in such children.Clinical symptoms and biochemical markers of GS and classic form of BS(type III) may overlap and thus genetic analysis may specify the real cause of symptoms.However,although genetic analysis is available,its use remains limited because of limited availability,large gene dimensions,lack of hot-spot mutations,heavy workup time and costs involved.Furthermore,considerable overlap exists between the different genotypes and phenotypes.Although BS and GS usually have distinct presentations and are associated with specific gene mutations,there remains considerable overlap between their phenotypes and genotypes.Thus,they are better described as a spectrum of clinical manifestations caused by different gene mutations.展开更多
Alzheimer’s disease is characterized by the extracellular accumulation of the amyloidβin the form of amyloid plaques and the intracellular deposition of the microtubule-associated protein tau in the form of neurofib...Alzheimer’s disease is characterized by the extracellular accumulation of the amyloidβin the form of amyloid plaques and the intracellular deposition of the microtubule-associated protein tau in the form of neurofibrillary tangles.Most of the Alzheimer’s drugs targeting amyloidβhave been failed in clinical trials.Particularly,tau pathology connects greatly in the pathogenesis of Alzheimer’s disease.Tau protein enhances the stabilization of microtubules that leads to the appropriate function of the neuron.Changes in the quantity or the conformation of tau protein could affect its function as a microtubules stabilizer and some of the processes wherein it is involved.The molecular mechanisms leading to the accumulation of tau are principally signified by numerous posttranslational modifications that change its conformation and structural state.Therefore,aberrant phosphorylation,as well as truncation of tau protein,has come into focus as significant mechanisms that make tau protein in a pathological entity.Furthermore,the shape-shifting nature of tau advocates to comprehend the progression of Alzheimer’s disease precisely.In this review,we emphasize the recent studies about the toxic and shape-shifting nature of tau in the pathogenesis of Alzheimer’s disease.展开更多
A significant fraction of the conventional oil reserves globally is in carbonate formations which contain a substantial amount of residual oil. Since primary and secondary recovery methods fail to yield above 20%-40%o...A significant fraction of the conventional oil reserves globally is in carbonate formations which contain a substantial amount of residual oil. Since primary and secondary recovery methods fail to yield above 20%-40%of original oil in place from these reserves, the need for enhanced oil recovery(EOR) techniques for incremental oil recovery has become imperative. With the challenges presented by the highly heterogeneous carbonate rocks,evaluation of tertiary-stage recovery techniques including chemical EOR(c EOR) has been a high priority for researchers and oil producers. In this review, the latest developments in the surfactant-based c EOR techniques applied in carbonate formations are discussed, contemplating the future direction of existing methodologies. In connection with this, the characteristics of heterogeneous carbonate reservoirs are outlined. Detailed discussion on surfactant-led oil recovery mechanisms and related processes, such as wettability alteration, interfacial tension reduction, microemulsion phase behavior, surfactant adsorption and mitigation, and foams and their applications is presented. Laboratory experiments, as well as field study data obtained using several surfactants, are also included.This extensive discussion on the subject aims to help researchers and professionals in the field to understand the current situation and plan future enterprises accordingly.展开更多
The success of any Intrusion Detection System (IDS) is a complicated problem due to its nonlinearity and the quantitative or qualitative network traffic data stream with many features. To get rid of this problem, seve...The success of any Intrusion Detection System (IDS) is a complicated problem due to its nonlinearity and the quantitative or qualitative network traffic data stream with many features. To get rid of this problem, several types of intrusion detection methods have been proposed and shown different levels of accuracy. This is why the choice of the effective and robust method for IDS is very important topic in information security. In this work, we have built two models for the classification purpose. One is based on Support Vector Machines (SVM) and the other is Random Forests (RF). Experimental results show that either classifier is effective. SVM is slightly more accurate, but more expensive in terms of time. RF produces similar accuracy in a much faster manner if given modeling parameters. These classifiers can contribute to an IDS system as one source of analysis and increase its accuracy. In this paper, KDD’99 Dataset is used and find out which one is the best intrusion detector for this dataset. Statistical analysis on KDD’99 dataset found important issues which highly affect the performance of evaluated systems and results in a very poor evaluation of anomaly detection approaches. The most important deficiency in the KDD’99 dataset is the huge number of redundant records. To solve these issues, we have developed a new dataset, KDD99Train+ and KDD99Test+, which does not include any redundant records in the train set as well as in the test set, so the classifiers will not be biased towards more frequent records. The numbers of records in the train and test sets are now reasonable, which make it affordable to run the experiments on the complete set without the need to randomly select a small portion. The findings of this paper will be very useful to use SVM and RF in a more meaningful way in order to maximize the performance rate and minimize the false negative rate.展开更多
AIM: To evaluate the safety and the efficacy of the ultrasound ciliary plasty(UCP) on the intraocular pressure(IOP) control in glaucomatous eyes without previous glaucoma surgery.METHODS: A retrospective study include...AIM: To evaluate the safety and the efficacy of the ultrasound ciliary plasty(UCP) on the intraocular pressure(IOP) control in glaucomatous eyes without previous glaucoma surgery.METHODS: A retrospective study included patients with primary and secondary glaucoma who underwent UCP in Dar Al Shifa Hospital, Kuwait between January 2017 to June 2018. High-intensity focused ultrasound procedures were performed under peribulbar anesthesia using the 2^(nd) generation probe with 8 s duration of each of the 6 shots. Complete ophthalmologic examinations were scheduled pre-treatment, and at 1 d, 1 wk, 1, 3, 6 and 12 mo posttreatment. Primary outcomes were the IOP reduction and success rates at 12 mo, while the secondary outcomes were the occurrence of vision threatening complications and visual acuity.RESULTS: The records of 62 eyes of 62 patients were analyzed with mean age of 63.8 y(67.7% males). There was statistically significant reduction in the mean IOP from 35.2±8.3 mm Hg before treatment to 20.6±8.7 mm Hg at 12^(th) month(P<0.0005) with a mean percentage IOP reduction of 42.3% with significant reduction in the mean number of antiglaucomatous drugs from 3.2±0.4 before treatment to 2.1±1.02 at 12 mo(P<0.0005). Qualified success was achieved in 77.4% of eyes at 12 mo. No major intra-or posttreatment complications were reported.CONCLUSION: Second-generation UCP prove to be effective in reducing IOP in naive glaucoma patients with lower success rates in cases of neovascular and uveitic glaucomas.展开更多
文摘Approximately 20% of patients with acute pancreatitis develop a severe disease associated with complications and high risk of mortality. The purpose of this study is to review pathogenesis and prognostic factors of severe acute pancreatitis (SAP). An extensive medline search was undertaken with focusing on pathogenesis, complications and prognostic evaluation of SAP. Cytokines and other inflammatory markers play a major role in the pathogenesis and course of SAP and can be used as prognostic markers in its early phase. Other markers such as simple prognostic scores have been found to be as e^ective as multifactorial scoring systems (MFSS) at 48 h with the advantage of simplicity, efficacy, low cost, accuracy and early prediction of SAP. Recently, several laboratory markers including hematocrit, blood urea nitrogen (BUN), creatinine, matrix metalloproteinase-9 (MMP-9) and serum amyloid A (SAA) have been used as early predictors of severity within the first 24 h. The last few years have witnessed a tremendous progress in understanding the pathogenesis and predicting the outcome of SAP. In this review we classified the prognostic markers into predictors of severity, pancreatic necrosis (PN), infected PN (IPN) and mortality.
基金supported by a major research grant from National Natural Science Foundation of China (Grant No. 30590370)National Science and Technology Support Program (Grant No. 2006BAJ10B02)
文摘Two wetland maps for the entire China have been produced based on Landsat data acquired around 1990 and 2000. Wetlands in China have been divided into 3 broad categories with 15 sub-categories except rice fields. In 1990, the total wetland area in China was 355208 km2 whereas in 2000 it dropped to 304849 km2 with a net loss of 50360 km2. During an approximate 10-year period, inland wetland reduced from 318326 to 257922 km2, coastal wetland dropped from 14335 to 12015 km2, while artificial wetland increased from 22546 to 34911 km2. The greatest natural wetland loss occurred in Heilongjiang, Inner Mon- golia, and Jilin with a total loss of over 57000 km2 of wetland. In western China, over 13000 km2 of wetlands were newly formed in Xinjiang, Tibet, and Qinghai. About 12000 km2 of artificial wetlands were also added for fish farm and reservoir constructions. The newly formed wetlands in western China were caused primarily by climate warming over that region whereas the newly created artificial wetlands were caused by economic developments. China’s wetland loss is caused mainly by human activities.
基金China-France Scientific end Technical Cooperation (No.1996-134)Bioengineering Key Laboratory of Henan Province
文摘INTRODUCTIONOnly the liver has the great capability ofregeneration in mammal.Few hepatocytes are inthe phase of division in the normal liver of an adultmammal (including human beings),but theremaining hepatocytes can be induced to proliferatequickly by partial hepatectomy (PH),and,to somedegree,they stop dividing and re-differentiate intocells functioning as hepatocytes.This shows
文摘BACKGROUND: Four different sizes (4, 5, 8 and 10 cm in diameter) can be found in the literature to categorize a liver hemangioma as giant. The present review aims to clarify the appropriateness of the size category "giant" for liver heman- gioma. DATA SOURCES: We reviewed the reports on the categoriza- tion of hemangioma published between 1970 and 2014. The number of hemangiomas, size criteria, mean and range of hemangioma sizes, and number of asymptomatic and symp- tomatic patients were investigated in patients aged over 18 years. Liver hemangiomas were divided into four groups: 〈5.0 cm, 5.0-9.9 cm, 10.0-14.9 cm and 〉15.0 cm in diameter. Inclu- sion criteria were noted in 34 articles involving 1972 (43.0%) hemangiomas (〉4.0 cm). RESULTS: The patients were divided into the following groups: 154 patients (30.0%) with hemangiomas less than 5.0 cm in diameter (small), 182 (35.5%) between 5.0 cm and 9.9 cm (large), 75 (14.6%) between 10.0 and 14.9 cm (giant), and 102 (19.9%) more than 15.0 cm (enormous). There were 786 (39.9%) asymptomatic patients and 791 (40.1%) symptomatic patients. Indications for surgery related to symptoms were reported in only 75 (3.8%) patients. Operations including 137 non-anatomical resection (12.9%) and 469 enudeation (44.1%) were undearly related to size and symptoms.CONCLUSIONS: The term "giant" seems to be justified for liver hemangiomas with a diameter of 10 cm. Hemangiomas categorized as "giant" are not indicated for surgery. Surgery should be performed only when other symptoms are apparent.
文摘Bartter and Gitelman syndromes(BS and GS) are inherited disorders resulting in defects in renal tubularhandling of sodium,potassium and chloride.Previously considered as genotypic and phenotypic heterogeneous diseases,recent evidence suggests that they constitute a spectrum of disease caused by different genetic mutations with the molecular defects of chloride reabsorption originating at different sites of the nephron in each condition.Although they share some characteristic metabolic abnormalities such as hypokalemia,metabolic alkalosis,hyperplasia of the juxtaglomerular apparatus with hyperreninemia,hyperaldosteronism,the clinical and laboratory manifestations may not always allow distinction between them.Diuretics tests,measuring the changes in urinary fractional excretion of chloride from baseline after administration of either hydrochlorothiazide or furosemide show very little change(< 2.3%) in the fractional excretion of chloride from baseline in GS when compared with BS,except when BS is associated with KCNJ1 mutations where a good response to both diuretics exists.The diuretic test is not recommended for infants or young children with suspected BS because of a higher risk of volume depletion in such children.Clinical symptoms and biochemical markers of GS and classic form of BS(type III) may overlap and thus genetic analysis may specify the real cause of symptoms.However,although genetic analysis is available,its use remains limited because of limited availability,large gene dimensions,lack of hot-spot mutations,heavy workup time and costs involved.Furthermore,considerable overlap exists between the different genotypes and phenotypes.Although BS and GS usually have distinct presentations and are associated with specific gene mutations,there remains considerable overlap between their phenotypes and genotypes.Thus,they are better described as a spectrum of clinical manifestations caused by different gene mutations.
基金the support by the Pharmakon Neuroscience Research Network, Dhaka, Bangladesh
文摘Alzheimer’s disease is characterized by the extracellular accumulation of the amyloidβin the form of amyloid plaques and the intracellular deposition of the microtubule-associated protein tau in the form of neurofibrillary tangles.Most of the Alzheimer’s drugs targeting amyloidβhave been failed in clinical trials.Particularly,tau pathology connects greatly in the pathogenesis of Alzheimer’s disease.Tau protein enhances the stabilization of microtubules that leads to the appropriate function of the neuron.Changes in the quantity or the conformation of tau protein could affect its function as a microtubules stabilizer and some of the processes wherein it is involved.The molecular mechanisms leading to the accumulation of tau are principally signified by numerous posttranslational modifications that change its conformation and structural state.Therefore,aberrant phosphorylation,as well as truncation of tau protein,has come into focus as significant mechanisms that make tau protein in a pathological entity.Furthermore,the shape-shifting nature of tau advocates to comprehend the progression of Alzheimer’s disease precisely.In this review,we emphasize the recent studies about the toxic and shape-shifting nature of tau in the pathogenesis of Alzheimer’s disease.
文摘A significant fraction of the conventional oil reserves globally is in carbonate formations which contain a substantial amount of residual oil. Since primary and secondary recovery methods fail to yield above 20%-40%of original oil in place from these reserves, the need for enhanced oil recovery(EOR) techniques for incremental oil recovery has become imperative. With the challenges presented by the highly heterogeneous carbonate rocks,evaluation of tertiary-stage recovery techniques including chemical EOR(c EOR) has been a high priority for researchers and oil producers. In this review, the latest developments in the surfactant-based c EOR techniques applied in carbonate formations are discussed, contemplating the future direction of existing methodologies. In connection with this, the characteristics of heterogeneous carbonate reservoirs are outlined. Detailed discussion on surfactant-led oil recovery mechanisms and related processes, such as wettability alteration, interfacial tension reduction, microemulsion phase behavior, surfactant adsorption and mitigation, and foams and their applications is presented. Laboratory experiments, as well as field study data obtained using several surfactants, are also included.This extensive discussion on the subject aims to help researchers and professionals in the field to understand the current situation and plan future enterprises accordingly.
文摘The success of any Intrusion Detection System (IDS) is a complicated problem due to its nonlinearity and the quantitative or qualitative network traffic data stream with many features. To get rid of this problem, several types of intrusion detection methods have been proposed and shown different levels of accuracy. This is why the choice of the effective and robust method for IDS is very important topic in information security. In this work, we have built two models for the classification purpose. One is based on Support Vector Machines (SVM) and the other is Random Forests (RF). Experimental results show that either classifier is effective. SVM is slightly more accurate, but more expensive in terms of time. RF produces similar accuracy in a much faster manner if given modeling parameters. These classifiers can contribute to an IDS system as one source of analysis and increase its accuracy. In this paper, KDD’99 Dataset is used and find out which one is the best intrusion detector for this dataset. Statistical analysis on KDD’99 dataset found important issues which highly affect the performance of evaluated systems and results in a very poor evaluation of anomaly detection approaches. The most important deficiency in the KDD’99 dataset is the huge number of redundant records. To solve these issues, we have developed a new dataset, KDD99Train+ and KDD99Test+, which does not include any redundant records in the train set as well as in the test set, so the classifiers will not be biased towards more frequent records. The numbers of records in the train and test sets are now reasonable, which make it affordable to run the experiments on the complete set without the need to randomly select a small portion. The findings of this paper will be very useful to use SVM and RF in a more meaningful way in order to maximize the performance rate and minimize the false negative rate.
文摘AIM: To evaluate the safety and the efficacy of the ultrasound ciliary plasty(UCP) on the intraocular pressure(IOP) control in glaucomatous eyes without previous glaucoma surgery.METHODS: A retrospective study included patients with primary and secondary glaucoma who underwent UCP in Dar Al Shifa Hospital, Kuwait between January 2017 to June 2018. High-intensity focused ultrasound procedures were performed under peribulbar anesthesia using the 2^(nd) generation probe with 8 s duration of each of the 6 shots. Complete ophthalmologic examinations were scheduled pre-treatment, and at 1 d, 1 wk, 1, 3, 6 and 12 mo posttreatment. Primary outcomes were the IOP reduction and success rates at 12 mo, while the secondary outcomes were the occurrence of vision threatening complications and visual acuity.RESULTS: The records of 62 eyes of 62 patients were analyzed with mean age of 63.8 y(67.7% males). There was statistically significant reduction in the mean IOP from 35.2±8.3 mm Hg before treatment to 20.6±8.7 mm Hg at 12^(th) month(P<0.0005) with a mean percentage IOP reduction of 42.3% with significant reduction in the mean number of antiglaucomatous drugs from 3.2±0.4 before treatment to 2.1±1.02 at 12 mo(P<0.0005). Qualified success was achieved in 77.4% of eyes at 12 mo. No major intra-or posttreatment complications were reported.CONCLUSION: Second-generation UCP prove to be effective in reducing IOP in naive glaucoma patients with lower success rates in cases of neovascular and uveitic glaucomas.