Abstract: To report on two patients with Coronavirus Disease 2019 (COVID-19) combined with diffuse connective tissue disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection followed for nearly 3 years, in order to understand the long-term effects on the patients' immune system. Both patients were male, aged 81-82 years, and were hospitalized with fever on January 29, 2020 and February 10, 2020, respectively. Both were diagnosed with COVID-19 after positive SARS-CoV-2 polymerase chain reaction (PCR) tests. After receiving anti-infection treatment, cough suppressants, ex‐pectorants, and symptomatic supportive treatment, their body temperature returned to normal and two consecutive PCR tests were negative for SARS-CoV-2, and they were discharged from hospital. However, due to recurring fevers and varying degrees of rheumatic disease-related symptoms, both patients were readmitted to the hospital, indicating the presence of positive auto‐ antibodies and organ involvement. One patient recovered from COVID-19 with recurrent fever, joint pain, muscle aches and subcutaneous nodules, and was subsequently diagnosed with undifferentiated connective tissue disease. The other patient developed recurrent fever, mouth ulcers and rash after recovery from COVID-19 and was subsequently diagnosed with anti neutro phil cytoplasm antibody (ANCA)-associated vasculitis (AAV). The patient was treated with glucocorticoids and immunosuppres sive drugs and the symptoms resolved rapidly and subsequent laboratory and imaging examinations showed stable condition. However, due to self-termination of medication, their symptoms quickly relapsed, and further treatment with glucocorticoids and immunosuppressive agents resulted in sustained stability of their condition. The erythrocyte sedimentation rate and hyper‐sensitive C-reactive protein remained within normal limits, and lung CT scans showed stable lesions with partial absorption.SARS-CoV-2 infection may have long-term effects on patients' immune systems, leading to abnormal immune responses and diffuse connective tissue disease. This suggests that regular follow-up observation of immune system-related diseases may be necessary for elderly patients with COVID-19.

Objective To investigate the correlation between obstructive sleep apnea syndrome(OSAS)with myocardial ischemia and arrhythmia.Methods To observe the occuring rate of premature beats and change of ST- segment,90 eases of OSAS patients were detected by the polysomnogram(PSG)and dynamic electrocardiogram at the same time.Results Total morbidity of myocardial ischemia was 32.2 % in OSAS patients,and it was 59.4 %, 15.8 %,20 % in serious,moderate and mild groups respectively.There was a statistically significant difference be- tween the three groups and the control group(P0.05).Conclusion As one of the risky factors of cardiovascular diseases,OSAS can induce myocardial ischemia and arrhythmia.

Objective To investigate the value of myocardial contrast echocardiography(MCE)combined with high-dose dobutamine stress echocardiography(DSE)in the early diagnosis of coronary artery disease(CAD).Methods The dobutamine stress MCE and SonoVue contrast infusion were performed before an elective percutaneous coronary intervention in 38 patients with suspected CAD.The total and regional perfusion were scored as normal or abnormal and attributed to the three main epicardial coronary arteries using a 16-segment left ventricular model.Results An intermediate stress level was obtained in 22(58%)patients,and 9(24%)patients were obtained with peak stress.Twenty seven of 38 patients were diagnosed as CAD by quantitative coronary angiography.A perfusion defect was detected in 89% of the patients at peak stress,compared to 37% at baseline,there was significant difference(χ2=15.565,P<0.01).ConclusionsThe MCE combined with DSE can increase the sensitivity of myocardial ischemia detection.As a new non-invasive method,MCE combined with DSE could be used in the early diagnosis of CAD.

Objective To investigate the value of high-dose dobutamine stress echocardiography combined with two-dimensional strain imaging in early diagnosis of coronary artery disease. Methods Highdose dobutamine stress echocardiography was performed to 28 patients with suspected coronary artery disease. All wall movements were observed during resting condition and at all stress levels,respectively;the peak systolic longitudinal strain in each endomyocardial segment of left ventricular was measured; the sensitivity and specificity between visual method and two-dimensional strain imaging in diagnosing myocardial ischemia with high-dose dobutamine stress echocardiography were compared. The average peak systolic longitudinal strain was calculated against control group, coronary artery disease group during ischemia segments and non-ischemia segments, and a comparison was made inside each group as well as against the other groups. The area under receiver operating characteristic curve of the peak systolic longitudinal strain was used to predict the sensitivity and the specificity of myocardial ischemia. Results With dobutamine dose of 40 μg·kg-1 · min-1 ,wall motion abnormalities were diagnosed in 6 patients (20 segments) through visual method, myocardial ischemia was found in 15 patients (148 segments) through computing the peak systolic longitudinal strain. Inside the coronary artery disease group during ischemic　segments,the majority of peak systolic longitudinal strain was significantly reduced ( P＜0.05) compared to the non-ischemic segments and the control group. In diagnosing myocardial ischemia in high-dose dobutamine stress echocardiography, the sensitivity of visual method and two-dimensional strain imaging were 35.3％ and 88.2％(P＜0.01), specificity 100％ and 100％(P＞0.05), and accuracy 60.7％ and 92.8％ (P＜0.01). The cutoff value of the peak systolic longitudinal strain was less than or equal to 14.9％, its sensitivity and specificity in predicting myocardial ischemia were 83.3％ and 91.7％,respectively. Conclusions High-dose dobutamine stress echocardiography combined with two-dimensional strain imaging can increase the sensitivity of detecting myocardial ischemia and detect concealed myocardial ischemia. High-dose dobutamine stress echocardiography combined with two-dimensional strain imaging can be used in early diagnosis of coronary artery disease.

Objective To establish a method for the rapid detection of hepatitis E virus (HEV)from serum samples based on fluorescence quantitative PCR.Methods (1 )One-hundred HEV sequences including our country popular three major genotypes were obtained from the GeneBank with the Vector NTI software.The proper sequence was selected to design and synthesize the primers of the fluorescence quantitation and the Taqman probe.(2)The amplification region PCR fragment was transcribed in vitro to synthesize cRNA standard,at the same time the trace serum virus lysate was introduced into a universal real-time TaqMan PCR assay.(3)10 clinical serum samples were collected from the patients with clinical hepatitis E and detected by using the established method for further verifying this method.Results This detection technique could effectively detect the serum samples in the pa-tients with genotype I and genotype IV hepatitis E positive,while the serum detection in the patients with other virus infectious dis-eases had the negative results,which verified that this RT-PCR detection technique had higher specificity and good reliability.The detection results from 10 clinical serum samples further verified that this method was rapid,convenient and sensitive with good re-peatability.Conclusion A fluorescence quantitative RT-PCR detection technique suitable for detecting main genotypes of HEV in China population is established,which can meet the demand of early and rapid diagnosis for HEV.

Objective To explore the effect of the midwife-leading labor pain management model on the pregnancy outcomes and pain control satisfaction.Methods The randomized grouping and single blind trial design were performed.One hundred and ten pregnant women were recruited and randomized into the control group (n=55) and intervention group (n=55).The control group received the routine prenatal examination by the outpatientdepartment obstetric doctors and intrapartum nursing care during labor.On this basis the intervention group participated in the labor pain educational course in the midwife clinic,and received the repeated pain assessment and pain management intervention during labor.Results There was no statistical difference in the delivery mode between the two groups(P＞0.05).The cesarean section rate without indication in the intervention group was significantly lower than that in the control group,the difference was statistically significant(x2 =6.798,P＜0.05).The average each item score of the labor pain education and pain control satisfaction in the intervention group was significantly higher than that in the control group,the difference was statistically significant(P＜0.01).Conclusion The midwife-leading labor pain management model can reduce the cesarean section rate without indication,and improves the satisfaction of labor pain education and pain control in pregnant women and parturients.

This study is to explore the reason of "the older, the better" of PCR and itsincrease of flavonoids. We identified the fun- gus isolated from the PCR using microscopic and molecular identification. HPLC method was used to determine the content of 4 fla- vonoids and to clarifythe regularity of them; UV spectrophotometry method was used to determine the total content of flavonoids; reverse thinking was applied to screen the fungus that have close relation to the change of flavonoids. Finally, we have isolated and identified 25 fungusfrom the PCR, which belong to 2 genus and 4 species, including pencillium commune, P. minioluteeum, P. citrinum, Aspergillus flavus and A. niger. The content of flavonoids was increased in the mildew PCR due to A. niger and other fungus. Therefore, "the ol- der, the better" of PCR had its scientific reason that the increase of flavonoids had a close relation of the metabolic activity of A. niger and other fungus.
Citrus ; chemistry ; microbiology ; Flavonoids ; analysis ; Fungi ; isolation & purification

Objective To investigate the incidence of Keshan disease(KSD) in Shandong province and to supply evidence for scientific control of the disease.Methods According to the scheme of KSD monitoring in Shandong province,the KSD cases were searched in 7 counties,and representative 3 counties and 6 villages were selected as key monitoring sites.In each site,about 420 residents were checked by asking detailed disease history,physical examination,and electrocardiography (ECG) tracings.Suspected cardiac abnormalities were taken chest posteroanterior X-ray film.At the same time,residents hair and food samples were collected to detect selenium levels in internal and external environments,and residents' income and per capita share of grain and other basic information were collected.Results ①Two hundred and fifty-nine medical units were searched,1132 cases of myocardial disease were found out and 638 suspected cases were identified and 142 chronic KSD cases were diagnosed.②In the 6 monitoring sites,2538 residents were surveyed and 91 cases of KSD were detected(of which 77 cases of potential,14 cases of chronic),the detection rate was 3.58％.A total of 2127 residents were traced ECG and the incidence of abnormal ECG was 24.5％ (521/2127),of which ST-T changes,T-wave changes,sinus bradycardia,sinus arrhymia,sinus tachycardia,and atrial premature beats et al were more common.Of the 75 X-ray films,39 cases had enlarged heart(in which 21 of mild,13 of moderate,5 of severe).③A total of 406 hair and grain samples were collected,respectively,and the selenium content of hair was approaching the level of appropriate,and the selenium content of food was still low.The annual per capita incomes of each site were between 3000 - 5900 Yuan,and residents main staple food was flour.Conclusions KSD in Shandong province is in a relatively stable situation.But latent and chronic KSD cases can still be detected.The internal environment selenium levels are elevated since the local living standards and dietary nutrition are improved.

Objective:To investigate the effect of blocking BRCAA1 gene expression with siRNA on the proliferation of tumor cell line MCF-7 and Rb gene expression.Methods:RNAi was employed to specifically knock down BRCAA1 expression.MCF-7 cells were transfected with complexes constructed with lipids and chemically synthesized Pre-designed anti-BRCAA1 siRNAs.The total RNA was isolated and reversely transcribed after 48 h.The expressions of BRCAA1 and Rb mRNA were determined by Real-Time PCR.Results:Compared with negative control,transfected MCF-7 cells had a 42.3% decrease in expression of BRCAA1 mRNA and an 11.1% increase in Rb mRNA expression.The inhibitory rate of MCF-7 cells proliferation was(81.6?6.1)%.Conclusion:There may be some antagonistic effect between BRCAA1 gene and Rb gene in proliferation of tumor cells,which provides a potential target for anti-tumor gene therapy.

Objective To explore the influencing factors on short -term efficacy of intravenous thrombolysis with rt -PA.Methods The clinical data of the 95 acute ischemic stroke(AIS)patients who received thrombolytic therapy were analyze.Multivariate logistic regression analysis was used to determine the possible influencing factors. Results Fifty -six(58.95%)patients had favourable outcomes after thrombolytic therapy for 24 hours.Multivariate logistic regression analysis indicated that diabetes(OR =3.933,95% CI 1.199 ~12.897)and TOAST classification (OR =1.448,95% CI 1.032 ~2.032 )were the independent predictors of short -term outcome.Conclusion Diabetes and TOAST classification are the major influencing factors of short -term efficacy after intravenous thrombolysis with rt -PA.It should pay attention screening patients for intravenous thrombolysis therapy and predicting the efficacy of thrombolysis.