Dermatology and venerology is a clinical discipline characterized by morphology.With the development of the internet and the application of internet in education,the features and advantages of internet teaching are gradually recognized including high flexibility,rich information and good student-teacher interaction.This article focused on the establishment and practice of internet teaching to improve teaching quality.

Objective To analyze MRI features of real tears and pseudotears of posterior horn of the lateral meniscus (PHLM) at the insertion site of meniscofemoral ligament(MFL), and to discuss main points of differential diagnosis. Methods MR images of 32 patients with PHLM tears and 30 patients with anterior cruciate ligament tears but without PHLM tears confirmed by arthroscopy were analyzed retrospectively. Another 20 asymptomatic volunteers as controls underwent MR examination and analyzed. The number of consecutive slices displaying longitudinal increased signal in sagittal images and the length in axial images were evaluated. The one?way analysis of variance, χ2 test and ROC curve were used to analyze diagnostic value of different MRI findings. Results Longitudinal line with abnormal increased signal (pseudotear) was found in 82.0% (41/50) normal insertion site of MFLs. The typical MRI finding of real tears was peripheral longitudinal linear high signal in PHLM which reached the margin of articular surface. In sagittal images, longitudinal linear high signal was shown in (5.8 ± 1.2) slices in knees of real tears, which was more than (2.6±1.1) slices and (2.7±1.4) slices in pseudo?tear groups (F=60.9, P<0.01). The area under ROC curve was 0.96 for differentiating real tear from pseudo-tear using the number of consecutive slices displaying longitudinal increased signal in sagittal images. With a threshold of five or more consecutive images with abnormal longitudinal increased signal as the positive standard of continuous?line sign, the overall sensitivity, specificity and accuracy for diagnosing real tear were 90.6%(29/32), 90.2%(37/41) and 90.4%(66/73), respectively. The axial images showed that the length of increased signal line in the outer of PHLM was (16.4±4.9) mm in patients with real tears, which was longer than pseudo?tear groups with length of (8.1 ± 3.2) mm and (6.0 ± 3.1) mm (F=17.0, P<0.01). The area under ROC curve was 0.92 for differentiating real tear from pseudo?tear using the length in axial images. The zip sign was defined when its length was not less than 10 mm. The sensitivity, specificity and accuracy of the zip sign was 84.4%(27/32), 90.2%(37/41) and 87.7%(64/73) respectively. In coronal images, high signal of MFL attachment insertion was shown in 71.9%(23/32), 60.0%(15/25) and 10/16 cases, there was no significant difference (χ2=0.98, P=0.61). Conclusion The continuous?line sign and zip sign are characteristic findings of PHLM tears at the insertion site of MFL attachment, which are valuable for differential diagnosis with pseudotears at the insertion site of MFL.

Hepatitis B virus (HBV)-induced hepatocellular carcinoma (HCC) is one of the most frequently occurring cancers. Hepadnaviral DNA integrations are considered to be essential agents which can promote the process of the hepatocarcinogenesis. More and more researches were designed to find the relationship of the two. In this study, we investigated whether HBV DNA integration occurred at sites of DNA double-strand breaks (DSBs), one of the most detrimental DNA damage. An 18-bp I-SceI homing endonuclease recognition site was introduced into the DNA of HepG2 cell line by stable DNA transfection, then cells were incubated in patients' serum with high HBV DNA copies and at the same time, DSBs were induced by transient expression of I-SceI after transfection of an I-SceI expression vector. By using nest PCR, the viral DNA was detected at the sites of the break. It appeared that integration occurred between part of HBV x gene and the I-SceI induced breaks. The results suggested that DSBs, as the DNA damages, may serve as potential targets for hepadnaviral DNA insertion and the integrants would lead to widespread host genome changes necessarily. It provided a new site to investigate the integration.

As resident immune cells of central nervous system(CNS),microglia play a key role in immune surveillance and tissue repair.They can be activated by various types of pathological factors to form M1 or M2 phenotype,which mediates neuroinflam-mation or neuroprotective effects.At the same time,when the homeostasis of the microenvironment in which the neuron is located is broken,"signal"molecules are also released to induce microglial activation through ligand-receptor binding.Therefore,the regulation of microglia-neuron connection is of great significance for treatment of nervous system diseases.This article reviews the signaling mole-cules involved in the two-way interaction between microglial cells and neurons,and elucidates the immune mechanisms of microglia-neuron,thus providing a basis for targeted treatment of CNS diseases related to microglia activation.

To explore the general clinical features and treatment outcomes of patients with AIDS-related diffuse large B-cell lymphoma (AIDS-DLBCL) and provide a theoretical basis for diagnosis and treatment, survival prognosis, prevention and management of AIDS-DLBCL patients. AIDS-DLBCL patients who received combined antiretroviral therapy (cART) at Changsha First Hospital from January 2017 to January 2020 were selected in this study. The survival curves were plotted using the Kaplan-Meier method, and the Cox proportional hazards regression model was used to analyze the association between AIDS-DLBCL specific variables and progression-free survival and overall survival. Correlation analysis was conducted based on the clinical features of the patients. A total of 50 AIDS-DLBCL patients were included. Their median age ( Q 1, Q 3) was 52 (44, 59) years, of whom 46 (92%) were male. About 20 (40%) patients received treatment with cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP), while 23 patients (46%) received treatment with rituximab combined with cyclophosphamide, doxorubicin, vincristine, and prednisone (RCHOP). Survival curve analysis showed that the 2-year progression-free survival rate and overall survival rate of AIDS-DLBCL patients were 56.9% and 61.6%, respectively. Patients with RCHOP protocol combined with EBV-DNA≥1 000 copies/ml had higher progression-free survival rate (χ 2=3.844, P=0.043) and overall survival rate (χ 2=4.662, P=0.031) than those with CHOP protocol combined with EBV-DNA≥1 000 copies/ml. A multivariate analysis showed that male ( HR=2.70, 95% CI:1.10-6.80), EB viral load≥1 000 copies/ml ( HR=1.75, 95% CI:1.12-2.84), HIV-RNA≥200 copies/ml ( HR=4.64, 95% CI: 1.73-12.15), ECOG PS score of 2 to 4 points ( HR=3.54, 95% CI:1.62-7.33), and international prognostic index (IPI) score of 3 to 5 points ( HR=5.21, 95% CI:1.39-20.14) were at a higher risk of disease progression. Patients with EB viral load≥1 000 copies/ml ( HR=0.07, 95% CI:0.05-0.93) on the RCHOP regimen had a small risk of disease progression. Males ( HR=2.87, 95% CI:1.65-9.17), EB viral load≥1 000 copies/ml ( HR=1.61, 95% CI:4.02-9.36), HIV-RNA≥200 copies/ml ( HR=1.19, 95% CI:1.58-2.74), ECOG PS score of 2 to 4 ( HR=6.42, 95% CI:2.55-14.33), IPI score of 3 to 5 points ( HR=2.78, 95% CI:1.41-12.96) had a high risk of mortality. Patients with EB viral load≥1 000 copies/ml ( HR=0.24, 95% CI:0.64-0.90) on the RCHOP regimen had a low risk of mortality. In summary, males, ECOG physical status score of 2 to 4 points, IPI score of 3 to 5 points, EB viral load≥1 000 copies/ml and HIV viral load≥200 copies/ml are risk factors affecting progression-free survival and overall survival of AIDS-DLBCL patients. RCHOP regimen combined with EB viral load≥1 000 copies/ml is a protective factor affecting progression-free survival and overall survival in AIDS-DLBCL patients.

To explore the general clinical features and treatment outcomes of patients with AIDS-related diffuse large B-cell lymphoma (AIDS-DLBCL) and provide a theoretical basis for diagnosis and treatment, survival prognosis, prevention and management of AIDS-DLBCL patients. AIDS-DLBCL patients who received combined antiretroviral therapy (cART) at Changsha First Hospital from January 2017 to January 2020 were selected in this study. The survival curves were plotted using the Kaplan-Meier method, and the Cox proportional hazards regression model was used to analyze the association between AIDS-DLBCL specific variables and progression-free survival and overall survival. Correlation analysis was conducted based on the clinical features of the patients. A total of 50 AIDS-DLBCL patients were included. Their median age ( Q 1, Q 3) was 52 (44, 59) years, of whom 46 (92%) were male. About 20 (40%) patients received treatment with cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP), while 23 patients (46%) received treatment with rituximab combined with cyclophosphamide, doxorubicin, vincristine, and prednisone (RCHOP). Survival curve analysis showed that the 2-year progression-free survival rate and overall survival rate of AIDS-DLBCL patients were 56.9% and 61.6%, respectively. Patients with RCHOP protocol combined with EBV-DNA≥1 000 copies/ml had higher progression-free survival rate (χ 2=3.844, P=0.043) and overall survival rate (χ 2=4.662, P=0.031) than those with CHOP protocol combined with EBV-DNA≥1 000 copies/ml. A multivariate analysis showed that male ( HR=2.70, 95% CI:1.10-6.80), EB viral load≥1 000 copies/ml ( HR=1.75, 95% CI:1.12-2.84), HIV-RNA≥200 copies/ml ( HR=4.64, 95% CI: 1.73-12.15), ECOG PS score of 2 to 4 points ( HR=3.54, 95% CI:1.62-7.33), and international prognostic index (IPI) score of 3 to 5 points ( HR=5.21, 95% CI:1.39-20.14) were at a higher risk of disease progression. Patients with EB viral load≥1 000 copies/ml ( HR=0.07, 95% CI:0.05-0.93) on the RCHOP regimen had a small risk of disease progression. Males ( HR=2.87, 95% CI:1.65-9.17), EB viral load≥1 000 copies/ml ( HR=1.61, 95% CI:4.02-9.36), HIV-RNA≥200 copies/ml ( HR=1.19, 95% CI:1.58-2.74), ECOG PS score of 2 to 4 ( HR=6.42, 95% CI:2.55-14.33), IPI score of 3 to 5 points ( HR=2.78, 95% CI:1.41-12.96) had a high risk of mortality. Patients with EB viral load≥1 000 copies/ml ( HR=0.24, 95% CI:0.64-0.90) on the RCHOP regimen had a low risk of mortality. In summary, males, ECOG physical status score of 2 to 4 points, IPI score of 3 to 5 points, EB viral load≥1 000 copies/ml and HIV viral load≥200 copies/ml are risk factors affecting progression-free survival and overall survival of AIDS-DLBCL patients. RCHOP regimen combined with EB viral load≥1 000 copies/ml is a protective factor affecting progression-free survival and overall survival in AIDS-DLBCL patients.

Hepatitis B virus (HBV)-induced hepatocellular carcinoma (HCC) is one of the most frequently occurring cancers. Hepadnaviral DNA integrations are considered to be essential agents which can promote the process of the hepatocarcinogenesis. More and more researches were designed to find the relationship of the two. In this study, we investigated whether HBV DNA integration occurred at sites of DNA double-strand breaks (DSBs), one of the most detrimental DNA damage. An 18-bp I-SceI homing endonuclease recognition site was introduced into the DNA of HepG2 cell line by stable DNA transfection, then cells were incubated in patients' serum with high HBV DNA copies and at the same time, DSBs were induced by transient expression of I-SceI after transfection of an I-SceI expression vector. By using nest PCR, the viral DNA was detected at the sites of the break. It appeared that integration occurred between part of HBV x gene and the I-Scel induced breaks. The results suggested that DSBs, as the DNA damages, may serve as potential targets for bepadnaviral DNA insertion and the integrants would lead to widespread host genome changes necessarily. It provided a new site to investigate the integration.

Objective:The purpose of this paper is based on the concept of enhanced recovery after surgery, to discuss the timing of taking food and water in knee arthroplasty patients, as well as its feasibility and safety, so as to improve the quality of quality nursing services.Methods:The 226 knee arthroplasty patients in Luoyang Orthopedic-Traumatological Hospital (Henan Provincial Orthopedic Hospital) from September 2020 to November 2021 were selected and divided into a control group and a experimental group using the random number table method, with 113 cases in each group. The control group adopted a conventional postoperative feeding management method; the experimental group adopted the early and timely feeding management method after comprehensive assessment. The data were compared between the two groups, including the incidence and severity of postoperative nausea and vomiting within 6 h and from 6 to 24 h after surgery , the incidence of thirst and hunger at 2 h, 4 h and 6 h postoperatively, and the comfort level.Results:The incidence of postoperative nausea and vomiting was lower in the experimental group [19.5%(22/113), 13.3%(15/113)] than in the control group [32.7%(37/113), 23.9%(27/113)] within 6 h and from 6 to 24 h after surgery, and the severity (21 cases of gradeⅠ, 10 cases of gradeⅡand 6 cases of grade Ⅲ) was also lower than in the control group (17 cases of gradeⅠ, 29 cases of gradeⅡand 18 cases of grade Ⅲ), and the differences were all statistically significant ( χ2 = 5.16,4.21, Z = -2.72, P<0.05). The incidence of thirst were lower in the experimental group [14.2%(16/113), 8.0%(9/113), 2.7%(3/113)] than in the control group [26.5%(30/113), 29.2%(33/113), 40.0%(35/113) at 2 h, 4 h and 6 h postoperatively, and the incidence of hunger at 4 h and 6 h postoperatively [11.5%(13/113), 8.0%(9/113)] were lower than in the control group [32.7%(37/113), 34.5%(39/113)], with statistically significant differences ( χ2 values were 5.35 to 32.39, all P<0.05). The postoperative comfort scale scores of physiological (31.04 ± 1.00) and psychological (33.50 ± 1.45) were higher in the experimental group than in the control group (27.46 ± 1.78) and (31.37 ± 1.29), and the differences were statistically significant ( t values were -102.36 to -66.26, all P<0.05). Conclusions:Early postoperative feeding management at the right time reduces the incidence and severity of postoperative nausea and vomiting inknee arthroplasty patients. In addition, it can also reduce the incidence of thirst and hunger, and improve patients′ postoperative physiological and psychological comfort, which has a facilitating effect on achieving rapid recovery of patients.

Objective To explore the correlation of MTHFD1 gene polymorphism with genetic susceptibility to colorec-tal cancer. Methods Ninety-six cases of colorectal cancer patients and 96 cases of healthy controls were investigated by questionnaire, the polymerase chain reaction - restriction fragment length polymorphism (PCR-RFLP) detection method was applied. Results Compared with normal control group, MTHFD1 G1958A polymorphism rs2236225 locus allele frequencies of patients with colorectal cancer had significant difference(P<0.05);rs2236225 genotype risk of col-orectal cancer increased 1.6 times(OR=1.603, 95%CI=0.331~2.534, P<0.05). Conclusion MTHFD1 gene polymorphism is closely related to the susceptibility of colorectal cancer, the main course of colorectal cancer is the rs2236225 gen changes in G1958A site of MTHFD1.

Objective:To investigate serum vitamin A and vitamin D status in children aged 2-<7 years in 20 cities in China.Methods:A cross-sectional study was conducted. A total of 2 924 healthy children aged 2-<7 years were recruited from September 2018 to September 2019 from 20 cities in China, categorized by age groups of 2-<3 years, 3-<5 years, and 5-<7 years. The demographic and economic characteristics and health-related information of the enrolled children were investigated. Body weight and height were measured by professional staff members. The serum vitamin A and vitamin D levels were detected by high-performance liquid chromatography-tandem mass spectrometry. Chi-square test and Logistic regression were applied to analyze the association between vitamin A and vitamin D deficiency and insufficiency as well as their underlying impact factors.Results:The age of the 2 924 enrolled children was 4.33 (3.42, 5.17) years. There were 1 726 males (59.03%) and 1 198 females (40.97%). The prevalences of vitamin A and vitamin D deficiency in enrolled children were 2.19% (64/2 924) and 3.52% (103/2 924), respectively, and the insufficiency rates were 29.27% (856/2 924) and 22.20% (649/2 924), respectively. Children with both vitamin A and vitamin D deficiencies or insufficiencies were found in 10.50% (307/2 924) of cases. Both vitamin A ( χ2=7.91 and 8.06, both P=0.005) and vitamin D ( χ2=71.35 and 115.10, both P<0.001) insufficiency rates were higher in children aged 3-<5 and 5-<7 years than those in children aged 2-<3 years. Vitamin A and vitamin D supplementation in the last 3 months was a protective factor for vitamin A and D deficiency and insufficiency, respectively ( OR=0.68 and 0.22, 95% CI 0.49-0.95 and 0.13-0.40, both P<0.05). The rates of vitamin A and D insufficiency was higher in children with annual household incomes <60 000 RMB than in those with annual household incomes ≥60 000 RMB ( χ2=34.11 and 10.43, both P<0.01). Northwest and Southwest had the highest rates of vitamin A and vitamin D insufficiency in children aged 2-<7 yeas, respectively ( χ2=93.22 and 202.54, both P<0.001). Conclusions:Among 20 cities in China, children aged 2-<7 years experience high rates of vitamin A and vitamin D insufficiency, which are affected by age, family economic level, vitamin A and vitamin D supplementation, and regional economic level. The current results suggest that high level of attention should be paid to vitamin A and vitamin D nutritional status of preschool children.