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OBJECTIVE To observe the effects of low-dose esketamine on analgesia and inflammatory factors after thoracoscopic surgery. METHODS Totally 120 patients who underwent thoracoscopic lobectomy in our hospital from October 2021 to March 2022 were selected and randomly divided into low-dose group （group A）， conventional-dose group （group B）， normal saline group （group C） by using the random number table method， with 40 patients in each group. All the patients were anesthetized with traditional general intravenous anesthesia， group A and B were anesthetized with low dose or normal dose （0.2 or 0.5 mg/kg） of Esketamine hydrochloride injection， and group C was given normal saline intravenously. The visual analog scale （VAS） score 0， 6， 24， 48 h after operation and the consumption of sufentanil 24 h after operation were compared among 3 groups. The levels of white blood cell count （WBC）， neutrophil percentage， C-reactive protein （CRP）， tumor necrosis factor-α （TNF-α）， interleukin-1 （IL-1） and IL-6 were compared 30 min before and 24 h after surgery. The Pittsburgh sleep quality index （PSQI） score and the Beck depression inventory （BDI） score were compared before operation and 0， 1， 2 d after operation， and the occurrence of adverse reaction was also recorded. RESULTS At 0， 6 and 24 h after operation， VAS scores and the consumption of sufentanil within 24 h after operation in group A and B were significantly lower than group C； VAS score 6 h after operation in group A was significantly lower than that in group B （P＜0.05）. The levels of WBC， neutrophil percentage， CRP， TNF-α， IL-1 and IL-6 in the 3 groups 24 h after surgery were significantly increased， compared with 30 min before surgery； the levels of above indexes in group A and B were significantly lower than those in group C （P＜0.05）. PSQI score and BDI score 0， 1 and 2 days after operation in group A and B were significantly lower than those in group C， while BDI score 0 day after operation in group A was significantly lower than that in group B （P＜0.05）. The total incidence of adverse reaction in group A， B and C were 5.0%， 10.0% and 17.5%， without statistical significance （P＞0.05）. CONCLUSIONS The low-dose esketamine has significant analgesic effect after thoracoscopic surgery， can reduce the levels of inflammatory factors after surgery and improve sleep quality and depression， with good safety.
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Emerging therapies based on localized delivery of siRNA to lungs have opened up exciting possibilities for treatment of different lung diseases. Localized delivery of siRNA to lungs has shown to result in severalfold higher lung accumulation than systemic route, while minimizing non-specific distribution in other organs. However, to date, only 2 clinical trials have explored localized delivery of siRNA for pulmonary diseases. Here we systematically reviewed recent advances in the field of pulmonary delivery of siRNA using non-viral approaches. We firstly introduce the routes of local administration and analyze the anatomical and physiological barriers towards effective local delivery of siRNA in lungs. We then discuss current progress in pulmonary delivery of siRNA for respiratory tract infections, chronic obstructive pulmonary diseases, acute lung injury, and lung cancer, list outstanding questions, and highlight directions for future research. We expect this review to provide a comprehensive understanding of current advances in pulmonary delivery of siRNA.
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Objective:To explore the effect of photobiomodulation (PBM) combined with umbilical cord mesenchymal stem cell transplantation on motor function recovery in rats with spinal cord injury.Methods:The mesenchymal stem cells were irradiated with a laser energy density of 1.5, 3, 6 and 12 J/cm 2. The optimal energy density was screened by the MTT method on the 3rd day. Before cell transplantation, 32 male SD rats were randomly divided into the spinal cord injury group, which was injected with normal saline without cells; the stem cell transplantation group, which was injected with stem cells in the injury model; the laser irradiation group, which was injected with cell-free saline and laser irradiation; and the combined treatment group, which was treated with cell transplantation and laser irradiation. BBB score and inclined plate test were performed on the 1st, 3rd, 7th, 14th and 21st day, and hematoxylin-eosin staining and Nissl staining were performed on the 21st day. Results:The laser irradiation with an energy density of 12 J/cm 2 can accelerate cell proliferation ( P<0.05). After the modeling, the BBB score of the combined treatment group was higher than that of the other groups (all P<0.05), and the motor function recovered significantly. In the inclined plate experiment, the performance of the combined treatment group and the laser irradiation group was also better than that of other groups. The results of hematoxylin-eosin staining showed that the cavity area in the combined treatment group was significantly reduced, and the inflammatory reaction was the lightest. The staining of Nissl bodies became deeper, and the spinal cord injury was significantly reduced. Conclusions:PBM can promote the recovery of motor function in rats with spinal cord injury after the transplantation of umbilical cord mesenchymal stem cells, and has an obvious therapeutic effect on spinal cord injury in rats. This study provides a basis for the treatment of spinal cord injury.
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Objective:To study the characteristics of breath sound spectroscopy in chronic obstructive pulmonary disease(COPD) patients with different lung function grades, to preliminarily determine the characteristic parameters and indicators of breath sound spectrograms with different lung function grades of COPD, and to explore the visualization and measurability of the differences in respiratory auscultation in patients with different lung function grades.Methods:Patients diagnosed and treated in Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine Chongming Branch from October 2018 to December 2020 were selected. Fifty-two patients with COPD (22 patients with moderate to moderate obstructive ventilation dysfunction (mild to moderate group), 30 patients with severe obstructive ventilation dysfunction (severe group)) and 36 normal controls (control group) were selected. The respiratory sounds were sampled with an electronic stethoscope and transmitted to the audit audio software to calculate the relevant data of respiratory sound pressure level (SPL) and the ratio to minute ventilation (VE) of samples with different lung function grades. A retrospective case-control study was used. The data with normal distribution were analyzed by one-way ANOVA, and the pairwise comparison was performed by SNK- q test. Results:The breathing audio frequency of mild-moderate, severe COPD patients and the control group has a sound pressure difference of (-0.5±2.2) dB and (-1.6±6.1) dB, (0.7±4.0) dB, and there was significant difference between each group ( F=2.64, P=0.038). The sound pressure level per minute ventilation (SPL 50-200/VE) of respiratory sound inspiratory phase in COPD patients with mild to moderate and severe obstructive ventilation dysfunction and the control group were (5.7±1.8) dB/L, (6.1±2.3) dB/L and (5.4±0.9) dB/L, respectively. The expiratory SPL 50-200/VE were (5.8±1.7), (6.3±2.2) and (5.3±1.2) respectively. There was significant difference among the three groups ( Finhalation=3.26, P=0.048; Frespiration=2.44, P=0.045). ROC curve results showed that SPL 50-200/VE in the inspiratory phase, SPL 50-200/VE in the expiratory phase, and sound pressure difference to assess different grades of obstructive ventilatory dysfunction had diagnostic value (AUC values were 0.697, 0.725 and 0.686, respectively; and P values were 0.015, 0.005 and 0.022, respectively). In some patients with COPD, abnormally high energy levels may appear in the time-frequency diagram of breath sounds. Conclusion:There are significant differences in respiratory audio spectrum analysis between patients with different degrees of obstructive ventilation dysfunction and those with normal ventilation function, which can provide a basis for auxiliary judgment of obstructive ventilation dysfunction.
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The prevalence rate of nonalcoholic fatty liver disease (NAFLD) is increasing year by year and it has become one of the most common chronic liver diseases in the world. Studies have shown that circular RNA (circRNA) is closely associated with NAFLD and is considered a potential diagnostic biomarker and therapeutic target for NAFLD. This article summarizes the regulatory role of circRNA in the pathogenesis of NAFLD and its value in diagnosis and treatment and points out that circRNA plays an important role in the development and progression of NAFLD and may have important clinical significance in the diagnosis and treatment of NAFLD.
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Objective To collect the serum samples of patients with nonalcoholic fatty liver disease (NAFLD), and to investigate the changes in serum metabolic biomarkers before and after lifestyle intervention. Methods A total of 23 patients who were diagnosed with NAFLD in Department of Gastroenterology and Inpatient Department, Putuo District Central Hospital of Shanghai, from January 2019 to January 2020 were enrolled, and all patients received the intervention with aerobic exercise and equicaloric low-carbohydrate high-protein diet. A total of 13 healthy volunteers who underwent physical examination in Physical Examination Center were enrolled as control group. For the patients with NAFLD, basic information was collected before and after intervention, blood samples were collected twice to measure liver function, blood glucose, and blood lipids, and part of serum was used for serum metabolomics analysis. The serum samples were analyzed by ultra-performance liquid chromatography/tandem high-resolution mass spectrometry. The data collected were processed in Compound Discover, and then principal component analysis (PCA) and orthogonal partial least squares discriminant analysis were used to establish the profile of differentially expressed blood metabolites between patients and healthy people and perform the enrichment analysis of differentially expressed metabolic pathways. The independent samples t -test was used for comparison of normally distributed continuous data between two groups, and the Wilcoxon non-parametric test was used for comparison of non-normally distributed continuous data between two groups. Results After lifestyle intervention, the patients had significant reductions in body mass index ( P < 0.01), body weight ( P < 0.01), and serum biochemical parameters alkaline phosphatase, albumin, gamma-glutamyl transpeptidase, and alanine aminotransferase (all P < 0.05), as well as a significant reduction in total protein ( P < 0.01), while there were no significant improvements in cholinesterase, aspartate aminotransferase, and glucose. As for the four items for blood lipids, there was a significant reduction in triglyceride ( P < 0.01), while there were no significant improvements in high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and total cholesterol. The metabolomics analysis showed that 33 serum metabolites changed significantly after lifestyle intervention. In addition, PCA results showed that after intervention, the level of metabolites in patients tended to be normal. The signaling pathway analysis showed that exercise and diet mainly affected the pathways of bile acid, unsaturated fatty acid synthesis, and phenylalanine metabolism. Conclusion Lifestyle intervention can achieve varying degrees of reduction in the body weight of patients with NAFLD, improve serum biochemical parameters, and regulate the abnormal metabolic pathway in patients with NAFLD, which has important clinical value and significance for guiding clinicians to formulate reasonable diet and exercise strategies for patients with NAFLD and prevent the progression of NAFLD.
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ObjectiveTo investigate the association between serum interleukin (IL) and liver pathological changes in patients with chronic hepatitis B (CHB). MethodsA total of 59 patients with CHB who were treated in Putuo District Central Hospital of Shanghai from February 2018 to February 2019 were enrolled as subjects, and liver biopsy was performed for all patients. According to the degree of liver inflammation, the patients were divided into mild inflammation (G1-G2) group and severe inflammation (G3-G4) group, and according to the degree of liver fibrosis, the patients were divided into mild fibrosis (S0-S2) group and severe fibrosis (S3-S4) group. Serum liver function parameters, blood lipids, interleukin-2 (IL-2), interleukin-6 (IL-6), interleukin-8 (IL-8), and interleukin-10 (IL-10) were measured for all patients. The independent samples t-test was used for comparison of normally distributed continuous data between two groups, and the Wilcoxon non-parametric test was used for comparison of non-normally distributed continuous data between two groups; the chi-square test was used for comparison of categorical data between groups. A Spearman correlation analysis was also performed. ResultsThe degree of liver fibrosis increased with the increase in liver inflammation (rs=0.538, P＜0.001). Compared with the mild inflammation group, the severe inflammation group had significantly higher serum levels of alanine aminotransferase ［95.00 (45.00-16925) U/L vs 51.00 (29.00-88.00) U/L, Z=-2.625, P=0.009］, aspartate aminotransferase ［54.50 (34.75-84.50) U/L vs 38.00 (30.00-49.00) U/L, Z=-2.014, P=0.044］, and gamma-glutamyl transpeptidase ［91.00 (56.72-192.25) U/L vs 44.00 (24.00-100.00) U/L, Z=-2.400, P=0.016］. The severe fibrosis group had a significantly higher serum level of high-density lipoprotein than the mild fibrosis group ［0.97 (0.32-1.08) mmol/L vs 1.23 (0.36-1.38) mmol/L, Z=-1.300, P=0.008］. The severe inflammation group had a significantly higher serum level of IL-2 receptor than the mild inflammation group ［704.00(418.00-103800) U/ml vs 436.00(335.00-555.00) U/ml, Z=-3.405, P=0.001］, and the severe fibrosis group had a significantly higher serum level of IL-2 receptor than the mild fibrosis group ［735.00(523.00-890.50) U/ml vs 447.00 (351.50-624.50) U/ml, Z=-5.358, P=0.001］. ConclusionThe degree of liver inflammation is positively correlated with that of liver fibrosis, while the serum level of IL-2 receptor increases with the increase in the degrees of liver inflammation and fibrosis, indicating that IL-2 receptor can reflect the degrees of liver inflammation and fibrosis to some extent.
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The incidence rate of nonalcoholic fatty liver disease (NAFLD) is increasing year by year and NAFLD has become one of the most common liver diseases in the world. Metabolomics follows the research thoughts of genomics and proteomics and conducts a quantitative analysis of all metabolites in organisms to explore the association between metabolites and physiological and pathological changes, which provides a new way for studying the traditional Chinese medicine diagnosis and treatment of NAFLD. This article summarizes the research advances in metabolomics and traditional Chinese medicine syndromes in NAFLD, so as to provide new thoughts and methods for further exploration of NAFLD.
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Objective@#To study the effects of Xiaoyaosan on sexual behavior and inflammatory factors of rat with depression.@*Methods@#The establishing depressive rat models of chronic mild unpredictable stress were established. The rats were randomly divided into model group and Xiaoyaosan group, 15 in each group. The Xiaoyaosan group was given 4.612 5 g/(kg•d) Xiaoyaosan, the blank group and the model group were intragastrically administered with normal saline once daily. After 4 weeks of oral administration, mount frequency and perineal licking numbers to female rats in each experimental group were observed by sexual behavior experiment, and the spleen index and thymus index were calculated. The serum DA, IL-1β, IL-6 levels were tested by Elisa.@*Results@#Compared with the normal group, the mount frequency (4.42 ± 3.91 vs. 11.58 ± 6.54), perineal licking numbers (3.53 ± 3.29 vs. 16.36 ± 10.68) and serum DA levels (14.14 ± 0.71 pg/ml vs. 17.44 ± 4.06 pg/ml) in the model group significantly decreased (P<0.05 or P<0.01), and the thymus index (0.012 4 ± 0.001 8 vs. 0.009 3 ± 0.001 7), serum IL-1β (39.45 ± 11.98 pg/ml vs. 28.62 ± 6.61 pg/ml), IL-6 levels (9.74 ± 1.49 pg/ml vs. 6.40 ± 0.66 pg/ml) significantly increased (P<0.05 or P<0.01). Compared with the model group, the contents of serum DA in Xiaoyaosan group (15.90 ± 1.24 pg/ml vs. 14.14 ± 0.71 pg/ml) increased significantly (P<0.01), and the thymus index (0.009 9 ± 0.001 3 vs. 0.012 4 ± 0.001 8) and IL-6 levels (8.32 ± 0.39 pg/ml vs. 9.74 ± 1.49 pg/ml) decreased significantly (P<0.05).@*Conclusions@#The Xiaoyaosan had a therapeutic effect on immune dysfunction and increases the expression of serum dopamine in depressive rats, which may be one of the mechanisms of its anti-depression.
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Though achieved great success as the only curative treatment for end-stage liver diseases, liver transplantation has been severely restricted by the shortage of donors. The adoption of extended criteria donor (ECD) tackles the donor shortage problem to some extent, thus became an issue we must face in China at present stage. As the transplantation effect and recipient safety is largely decided by the quality of liver graft, ECD graft should be cautiously selected and adopted because of its inherent defects. This relies on individualized decisions made for recipients by transplant surgeons who have a good understanding of the risk factors and evaluation criteria of ECD. In this article, we investigate the risk factors, evaluation criteriaand allocation of ECD liver grafts as well as the application of mechanic perfusion, and we discuss the fundamental issues and prospects of ECD study.
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Though achieved great success as the only curative treatment for end-stage liver diseases, liver transplantation has been severely restricted by the shortage of donors. The adoption of extended criteria donor (ECD) tackles the donor shortage problem to some extent, thus became an issue we must face in China at present stage. As the transplantation effect and recipient safety is largely decided by the quality of liver graft, ECD graft should be cautiously selected and adopted because of its inherent defects. This relies on individualized decisions made for recipients by transplant surgeons who have a good understanding of the risk factors and evaluation criteria of ECD. In this article, we investigate the risk factors, evaluation criteriaand allocation of ECD liver grafts as well as the application of mechanic perfusion, and we discuss the fundamental issues and prospects of ECD study.
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OBJECTIVE:To provide reference for rational drug use in clinic and nosocomial infection control. METHODS:Acinetobacter baumannii(AB)were collected from our hospital during Jan. 2014-Jun. 2017. Drug sensitivity tests were conducted by using K-B method and MIC method. Drug-resistance genes of multidrug-resistant Acinetobacter baumannii(MDR-AB)were amplified by PCR,and compared with GenBank database by using Blast comparison. RESULTS:A total of 1 758 strains of AB were detected,and mainly came from sputum and throat swab(65.24%),followed by urine(18.49%). These infected patients were mainly distributed in the departments of ICU(38.51%)and respiratory medicine(24.00%),respectively. Drug resistance of clinical isolated AB to most commonly used antibiotics were more than 40%,such as compound sulfamethoxazole,piperacillin sodium and tazobactam sodium,gentamicin,cefepime,levofloxacin,minocycline,imipenem,etc.;it had increased year after year. Drug resistance to colistin was lower than 5% and decreased year by year.A total of 673 strains of MDR-AB were detected, and detection rates were 22.77%,29.82%,52.09%,54.33%,respectively.Among 110 strains of MDR-AB,detection rates of TEM, AmpC,IMP,VIM,OXA-23,OXA-24,OXA-51,aac(6′)-Ⅰ,aac(3)-Ⅰ,ant(3″)-Ⅰ,anmA,gyrA,parC gene were 97.27%, 91.82%,49.09%,12.73%、90.91%,12.73%,98.18%,34.55%,60.91%,89.09%,87.27%,77.27%,82.73%,respectively. Results of Blast comparison showed that point mutation occurred in 83rd and 121st base of gyrA gene,144th base of parC gene. CONCLUSIONS:AB mainly come from sputum and throat swab specimens in our hospital,and infected patients are mainly distributed in the departments of ICU and respiratory medicine. Drug resistance is serious,and the detection rate of MDR-AB is increased year by year. Main genes of multidrug-resistant strains mainly include TEM,AmpC,OXA-23,OXA-51,ant(3″)-Ⅰ, anmA,etc.,and mutation of gyrA and parC gene are found. It is necessary to strengthen the management of classification use of antibiotics and strengthen the monitoring of AB drug resistance. According to the results of drug sensitivity test,antibiotics are selected rationally to prevent or delay planting and cross transmission of AB-resistant strain.
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Objective To observe any effect of intensive training on the degree of depression and the expression of Kalirin-7 in the hippocampus of rats modeling with post-stroke depression,and to investigatc possible mechanisms.Methods Forty male Wistar rats were randomly divided into a post-stroke depression (PSD) group,a routine training group,an intensive training group and a sham-operation group (n =10 for each group).All except the sham-operation group were given the middle cerebral artery occlusion using the intraluminal thread method,and chronic mild stress was applied.The PSD group and the sham-operation group were not given any training.The routine training group was trained oncc a day,and the intensive training group was trained twice a day.The sucrose preference test,open field test and forced swimming test were conducted at the outset and after 14 and 28 days of training.The expression of Kalirin-7 in the left hippocampus was detected using Western blotting.Results After 14 days of training,significant differences were found in the test results of the sham-operation group compared with the other groups (P＜0.05).There were also significant differences in the average results on all 3 tests among all of the groups except the sham-operation group.At both 14 and 28 days after training,the average expression of Kalirin-7 in both the routine and intensive training groups was significantly higher than in the PSD group (P＜0.05),and that of the intensive training group was significantly higher than that of the routine training group at the same time points (P＜0.05).Conclusion Intensive training can relieve depression and increase the expression of the Kalirin-7 in the hippocampus,at least in rats.
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Objective To observe the effects of treadmill training at different intensities on the expression of p-AKT in rats' gastrocnemius muscles after focal cerebral ischemia,and to investigate whether intensive training is beneficial for the recovery of motor function.Methods Left middle cerebral artery occlusion (MCAO) was induced in 120 male Wistar rats using the intraluminal thread method,and they were divided into an MCAO group (no training),a normal training group (treadmill training once a day for 30 min) and an intensive training group (treadmill training twice a day for 60 min),each of 30 rats.There was also a sham control group with 30 members not given MCAO or training.The four groups were further divided into 3 day,7 day and 14 day subgroups.Five rats randomly selected from each subgroup were sacrificed for hematoxylin-eosin staining after 4％ paraformaldehyde treatment.Neurological function was evaluated using Zausinger scores,and the expression of p-Akt was detected by western blotting.Results No significant differences in Zausinger scores were observed between the intensive training group and the normal training group after 1,3 or 7 days of training.However the average Zausinger score in the intensive training group was significantly higher than in the normal training group after 14 d of treadmill training.After 7 d and 14 d of treadmill training the average cross-sectional area of the gastrocnemius muscles in the sham group was significantly higher than in the other three groups.The average area of the intensive training group was significantly larger than that of the normal training group.The expression of p-Akt in the gastrocnemius was significantly increased in the intensive training group compared with the normal training group in the 7 day and 14 day subgroups.Conclusion Treadmill training can improve the expression of p-Akt in atrophied gastrocnemius muscles caused by MCAO.Intensive training is more effective for the recovery of muscle function.
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Objective To investigate the effects of treadmill training at different intensities on neurological function and expression of kalirin-7 in rats after cerebral ischemia-reperfusion,and the possible mechanism.Methods Sixty Wistar male rats were randomized into a model group,a routine training group,an intensive training group and a sham-operation group (n =15 for each group).A middle cerebral artery occlusion/reperfusion (MCAO/R) model was established in all the rats of the first three groups.The model group and sham group did no motor training,while the utine training group did treadmill training once daily,and the intensive training group did treadmill training twice a day.On the 3rd,7th and 14th day,Zausinger scores was used to evaluate the neurological deficit;reverse Transcription PCR (RT-PCR) and Western blot were adopted to detect the expression of kalirin-7 and kalirin-7 mRNA in the peri-ischemic brain tissues respectively.Results The average Zausinger scores of the model group and 2 training groups were significantly lower than that of the sham-operation group at all time points;on the 7th and 14th days,the average score of the intensive training group was significantly higher than that of the outine training group.Moreover,the expression of kalirin-7 and kalirin-7 mRNA in the MCAO rats were significantly lower than that in the sham-operation group.On days 7 and 14,the expression of kalirin-7 in the intensive training group was significantly higher than that of the routine training group,which was still significantly higher than the model group.On day 14,the expression of kalirin-7 mRNA in the intensive training group was significantly higher than that of the routine training group,which was still significantly higher than the model group.Conclusion The intensive training is superior to routine training in promoting neural functional recovery and expression of kalirin-7 in rats with cerebral ischemia-reperfusion.
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Objective To observe the effects of selfmade Lifeihuayu decotion in the treatment of patients with bronchial asthma.Methods 102 patients with bronchial asthma were randomly divided into the observation group and the control group,each group had 51 cases.The patients in the control group were treated with the conven-tional treatment,while the patients in the observation group were treated with the conventional treatment plus selfmade Lifeihuayu decotion.They were treated for 8 weeks.The patients of the two groups were determined with lung function and blood gas analysis, including forced expiratory volume in one second ( FEV1 ) , forced inspiratory vital capacity ( FVC) ,peak expiratory flow( PEF) ,pH value,the partial pressure of oxygen( PaO2 ) and carbon dioxide partial pres-sure(PaCO2).Results The total effective rate were 98.0% in the observation group and 90.2% in the control group,the total efficiency of the observation group was significantly higher(χ2 =5.78,P<0.05).After treatment,the FEV1,FVC and PEF of the patient's in the two groups were significantly increased(t=5.325,4.821,2.761,all P<0.05),and compared with the control group,the FEV1,FVC and PEF of patients in the observation group improved more significantly(t=2.068,2.771,3.013,all P<0.05).After treatment,the PaO2 of the patient's in the two groups were significantly higher,which more obviously increased in the observation group than those in the control group( t=2.925,P<0.05).After treatment,the PaCO2 of the patient's in the two groups were significantly decreased,PaCO2 in the observation group significantly decreased more than that in the control group(t=3.063,P<0.05).Conclusion Selfmade Lifeihuayu decotion in the treatment of patients with bronchial asthma has curative effect,and can signifi-cantly improve lung function and blood gas analysis of patients.
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In order to enhance the position accuracy of ablation catheter in heart electrophysiology operation, signals of respiration and heartbeat must be removed for subsequent data processing. Based on locating principle of electrical field with low frequency, synchronous detector with MC1496 has been developed in this study. In the present research, several methods are utilized to optimize the circuit performance, such as coupling and stopping direct current, low-pass filtering, as well as limiting ripple voltage etc. Through simulation results, it showed that the demodulation performance of the circuit was fine. Through simulation platform of thorax electric field and animal experiment, the circuit feasibility were further proved good for extracting signals of respiration and heartbeat.