Single nucleotide polymorphisms (SNPs) are genetic variations that determine the differences between any two unrelated individuals. Various population groups can be distinguished from each other using SNPs. For instance, the HapMap dataset has four population groups with about ten million SNPs. For more insights on human evolution, ethnic variation, and population assignment, we propose to find out which SNPs are significant in determining the population groups and then to classify different populations using these relevant SNPs as input features. In this study, we developed a modified t-test ranking measure and applied it to the HapMap genotype data. Firstly, we rank all SNPs in comparison with other feature importance measures including F-statistics and the informativeness for assignment. Secondly, we select different numbers of the most highly ranked SNPs as the input to a classifier, such as the support vector machine, so as to find the best feature subset corresponding to the best classification accuracy. Experimental results showed that the proposed method is very effective in finding SNPs that are significant in determining the population groups, with reduced computational burden and better classification accuracy.

Single nucleotide polymorphisms (SNPs) are genetic variations that determine the differences between any two unrelated individuals. Various population groups can be distinguished from each other using SNPs. For instance, the HapMap dataset has four population groups with about ten million SNPs. For more insights on human evolution, ethnic variation, and population assignment, we propose to find out which SNPs are significant in determining the population groups and then to classify different populations using these relevant SNPs as input features. In this study, we developed a modified t-test ranking measure and applied it to the HapMap genotype data. Firstly, we rank all SNPs in comparison with other feature importance measures including F-statistics and the informativeness for assignment. Secondly, we select different numbers of the most highly ranked SNPs as the input to a classifier, such as the support vector machine, so as to find the best feature subset corresponding to the best classification accuracy. Experimental results showed that the proposed method is very effective in finding SNPs that are significant in determining the population groups, with reduced computational burden and better classification accuracy.
Algorithms ; Computational Biology ; Databases, Nucleic Acid ; Genetics, Medical ; statistics & numerical data ; Genetics, Population ; Genomics ; statistics & numerical data ; Genotype ; Humans ; Polymorphism, Single Nucleotide

At present,the strategy of setting the optimal positive end-expiratory pressure(PEEP)for mechani-cal ventilation still needs further clinical exploration.Electrical impedance tomography(EIT)is a newly devel-oped technology at the end of the 20th century.It can monitor pulmonary ventilation in real time,so is exten-sively important to optimal PEEP setting.This review summarizes the principles of using EIT to guide PEEP setting,monitoring respiratory system compliance,spatial distribution,temporal distribution,local lung perfu-sion and other information published in recent years,analyzes the basic and clinical research information relat-ed to PEEP effect and its application in individualized PEEP setting.

Objective:To compare the clinical efficacy and complications of intra-arterial chemotherapy (IAC) and intravenous chemotherapy (IVC) for unilateral advanced retinoblastoma (RB).Methods:A retrospective clinical study. From January 2020 to January 2021, 40 patients (40 eyes) unilateral group cT2 RB patients diagnosed at Baoding Children’s Hospital and Beijing Children’s Hospital were recruited in this study. There were 22 males (22 eyes) and 18 females (18 eyes). All were monocular. All the patients were assigned to two groups according to different treatment modalities they received: IVC group and IAC group. There were 26 eyes and 14 eyes, respectively. When the tumor invades the optic nerve, choroid, sclera, anterior chamber and iris, enucleation was performed. The globe salvage rate, tumor extraocular metastasis rate, solid tumor control rate, treatment-related complications and pathological high-risk factors after enucleation were observed. The globe salvage rate and solid tumor control rate were compared between the groups by chi square test.Results:The globe salvage rate of IAC group and IVC group were 88.5% (23/26) and 50.0% (7/14), respectively. Solid tumor control of IAC group and IVC group were 84.6% (22/26) and 42.9% (6/14), respectively. There were statistically significant differences in globe salvage rate and solid tumor control between the two groups ( χ 2=7.18, 7.56; P<0.05). Compared with IVC group, IAC group had less systemic complications, mild ocular and periocular side effects. Among 26 cases in IAC group and 14 cases in IVC group, 3 and 7 cases underwent enucleation respectively. The results of pathological examination showed that there were 2 cases and 3 cases with pathological high-risk factors in the two groups, respectively. During the follow-up period, 2 cases in IAC group had extraocular metastasis, there was no extraocular metastasis in IVC group. Conclusion:Compared with IVC, IAC has the advantages of high tumor control rate, high globe salvage rate, less and mild complications, however, there is still tumor recurrence.

The incidence and mortality of venous thromboembolism (VTE) are high in critically ill patients, and there is still a risk of VTE and bleeding after the use of fixed-dose low molecular weight heparin (LMWH) for prophylaxis. The level of anti-factor Ⅹa is not up to standard after LMWH prophylaxis in patients with surgery or trauma. The condition of critically ill patients is complicated, and the proportion of patients with low antithrombin Ⅲ is high, which can affect the prophylactic efficacy of LMWH and contribute to VTE occurrence. There is currently no consensus on whether adjusting LMWH dose according to anti-factor Ⅹa levels can reduce VTE occurrence in critically ill patients. High-quality multicenter randomized controlled studies are needed in the future to establish new approaches for precise prevention of VTE in critically ill patients.

BACKGROUND: The aim of this study was to analyze the incidence of lower limb deep venous thrombosis (DVT) and the corresponding coagulation status in severe patients after thoracic surgery. METHODS: Severe patients after thoracic surgery who received mechanical prophylaxis of lower limb DVT between July 2016 and June 2018 were analysed retrospectively. Their general information, disease species, surgical treatment, and coagulation index were reviewed. RESULTS: Fifty patients were finally included. There were 34 male and 16 female, aging from 22 to 80 years. The incidence of DVT was 22.0%, all of them were isolated calf DVT. The incidence was 29.4% in male patients, while 6.3% in female; 23.5% in malignant diseases and 18.6% in benign. All coagulation index presented no statistical difference between patients with and without DVT, except activated partial thromboplastin time (APTT). CONCLUSIONS Even on the basis of adequate mechanical prophylaxis, lower limb DVT is common in severe patients after thoracic surgery. Meanwhile, male patients and malignant diseases are more suscepted.
Adult ; Aged ; Aged, 80 and over ; Blood Coagulation ; Female ; Humans ; Incidence ; Lower Extremity ; blood supply ; Lung Neoplasms ; surgery ; Male ; Middle Aged ; Retrospective Studies ; Thoracic Surgical Procedures ; adverse effects ; Venous Thrombosis ; etiology ; physiopathology ; Young Adult