Traditional mass measurement methods are not applicable in microgravity environments,and the main challenge for in-orbit body mass measurement technology based on inertial principles is to address the random errors brought about by the weightless environment.These include additional torques due to shifts in the center of mass,nonlinear accelerations due to non-rigid human bodies,mechanical energy consumption due to organ vibrations,and random vibrations of the measurement device itself.To address the above difficulties,the project proposes a technical scheme based on the principle of linear acceleration,designs and constructs a ground-specific air-floating experimental and simulation platform,studies key data such as motion trajectory,acceleration change,and vibration frequency amplitude during the mass measurement process,and simulates the changes in the center of mass and random vibrations of the human body in a weightless environment.The project has designed an adjustable posture bracket to adapt to changes in the center of mass,enhance body restraint,and greatly reduce shaking;it has also developed an integrated four-bar linkage motion guidance mechanism,high-precision integrated photoelectric distance measurement,and modular motion constant force measurement device to ensure the accurate measurement of acceleration and constant force data.The product has undergone simulation calculations,ground human applicability tests,and in-orbit applicability verification in the space station.Ground test results show that the device achieves a body mass measurement accuracy better than 0.5%,and the dispersion is better than 0.38%;after flight mission verification and evaluation,the in-orbit body mass measurement dispersion is less than 0.4%,which is superior to the SLAMMD,a mass measurement device of the same principle on the International Space Station,and is at the forefront internationally,achieving accurate body mass measurement.

Objective:Measure the global longitudinal strain (GLS) of the left ventricle in trauma patients by beside speckle tracking echocardiography to explore the role of STE -GLS in evaluating left ventricular systolic function in trauma patients, and then explore the clinical value of GLS in judging the prognosis of trauma patients.Methods:Trauma patients admitted to intensive care unit from September 1, 2020 to April 1, 2021 with an Injury Severity Score (ISS) of ≥ 16 points. were consecutively enrolled. Moreover, those patients who met the following criteria were selected as the research subjects: aged between 18 and 80 years old, had no serious underlying diseases in the past, the time from trauma onset to admission was within 24 hours, and were able to complete an echocardiogram examination within 24 hours after the onset of the disease. Exclude patients who are unable to complete the ultrasound examination within 24 hours after the onset of the disease, or those with poor image quality, or those complicated with severe heart diseases and systemic comorbidities. The left ventricular global longitudinal strain (GLS) was measured by bedside speckle tracking echocardiography. According to the GLS values they were divided into abnormal group (GLS> -15%) and normal group (GLS≤ -15%). Independent sample t-tests and chi-square tests were applied to conduct a comparative analysis of the clinical characteristics between the two groups of patients. Furthermore, multiple linear regression analysis was conducted to explore the correlation between STE-GLS and the duration of intensive care unit stay.Results:A total of 32 trauma patients were eligible for this study. One patient was found to have abnormal left ventricular systolic function (LVEF<50%) detected by conventional echocardiography, however speckle tracking echocardiography detected decreased left ventricular systolic function (GLS> -15%) in 13 Patients. Multiple linear regression analysis showed that the global longitudinal strain of left ventricle and serum high sensitivity troponin I were independent risk factors affecting the time of intensive care in trauma patients.Conclusions:Speckle tracking echocardiography (STE) is more sensitive than traditional echocardiography and can detect left ventricular systolic dysfunction early. STE-GLS is an independent risk factor affecting hospitalization time of trauma patients in intensive care unit. Clinically, STE-GLS and serum Hs-TnI can be combined to determine the prognosis of trauma patients.

Objective:To analyze the clinical characteristics of invasive klebsiella pneumoniae liver abscess syndrome (IKPLAS), and compare it with common pyogenic liver abscess (CPLA). Methods:The social demography and clinical data of inpatients with pyogenic liver abscess from January 2011 to December 2021 in the Peking University People's Hospital were collected. Based on the presence or absence of invasive infections and the results of bacterial etiology, IKPLAS was diagnosed and compared with CPLA. The general information, symptoms, past medical history, auxiliary examinations and prognosis indicators of the two groups of patients were compared.Results:Total of 172 patients with pyogenic liver abscess were collected, including 25 cases of IKPLAS. Compared with CPLA group, the proportion of fever in IKPLAS group was lower, the proportion of diabetes history was higher, the proportion of monocytes was lower, and procalcitonin and urea nitrogen were higher(all P<0.05), the proportion of multiple abscesses is higher, and the positive rate of blood culture and the cultivation of klebsiella pneumoniae are both higher (all P<0.05).A total of 9 cases (5.2%) of patients developed septic shock, of which 2 cases (1.2%) died. The IKPLAS group had a higher proportion of ICU admissions ( P<0.05),but but the difference of mortality between the two groups was not statistically significant ( P>0.05). The most common sites of invasion infection in the IKPLAS group are the lungs(22/25), brain(9/25), and eyes(9/25). Conclusions:There are differences in clinical characteristics between IKPLAS and CPLA, the most common sites of invasion infection are the lungs, brain, and eyes, but there is no difference in mortality in this study. For PLA with pathogenic Klebsiella pneumoniae, it is necessary to carefully evaluate the presence of invasive lesions and provide targeted local treatment to better improve prognosis.

Objective:To analyze the clinical characteristics and risk stratification of 182 patients with acute pulmonary embolism (APE), and to investigate the correlation of neutrophil (N)/lymphocyte (L) ratio (NLR) and risk stratification/prognosis.Methods:The clinical data of 182 APE patients admitted to Peking University People’s Hospital from January 2015 to March 2021 were retrospectively collected, including age, sex, symptoms and signs, blood pressure, blood gas analysis, blood routine parameters, cardiac biomarkers, coagulation parameters, and right ventricular imaging parameters. The patients were divided into groups according to the risk stratification at admission and prognosis in hospital. χ2 test, t test or nonparametric test were used to analyze the differences in clinical characteristics, blood routine parameters, blood gas analysis, coagulation parameters and other parameters between the groups. Multivariate logistic regression analysis was used to study the independent risk factors for the prognosis of APE. Results:Among the 182 patients, 79 were male and 103 were female, 23 were in the high-risk group, 51 were in the intermediate-high-risk group, 46 were in the intermediate-low risk group, and 62 were in the low-risk group. There were 27 deaths and 155 survivors. The respiratory rate of the high/intermediate-high-risk group was significantly higher than that of the low/intermediate-low-risk group. Compared with the other three groups, pH, oxygen partial pressure (PO 2) and blood oxygen saturation (SO 2) in the high-risk group were significantly lower ( both P<0.05). There were statistically significant differences in WBC, N, and NLR levels between the high/intermediate-high-risk group and low/intermediate-low-risk group ( both P<0.05). However there were no significant differences in PLT, PLT/MPV, PLT/PDW, and coagulation related parameters PT, FIB, APTT and D-D between groups (all P > 0.05). MPV and PDW were only significantly different between the low-risk group, intermediate-low-risk group and high-risk group ( both P<0.05). Multivariate logistic regression analysis showed that NLR ( OR=1.179,95% CI:1.029-1.410, P=0.039) and PH ( OR=1.156,95% CI:1.031-1.522, P=0.041) were independent predictors of in-hospital mortality. The ROC curve was used to analyze the predictive value of NLR for in-hospital mortality. When the cutoff value of NLR was 8.38, the AUC of NLR was 0.824 (95% CI: 0.829-0.913), the corresponding sensitivity was 0.831, and the specificity was 0.887. Conclusions:NLR is correlated with risk stratification and prognosis of APE, and is an independent risk factor for poor prognosis.

Objective:To explore the value of neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR) combined with bedside index for severity in acute pancreatitis (BISAP) score in predicting severe acute pancreatitis (SAP) in patients with hypertriglyceridemia pancreatitis (HTGP).Methods:Patients who met the diagnostic criteria of HTGP were retrospectively collected in the Emergency Department of Peking University People's Hospital from January to December in 2019. Patients were assigned to two groups according to the severity of acute pancreatitis: the mild acute pancreatitis group and severe acute pancreatitis (SAP) group. Blood samples were taken within 24 h after the onset of HTGP for analysis. White blood cell count, neutrophil count, lymphocyte count, and other laboratory indicators were detected. BISAP score was performed, and NLR and PLR were calculated in all patients within 24 h of the onset of HTGP. Comparison of various indicators was performed in the two groups. The risk factors of SAP patients with HTGP were analyzed by Logistic regression. The correlation of risk factors was analyzed by correlation. The receiver operating characteristic (ROC) curve was drawn, and the optimal thresholds of NLR and PLR were calculated respectively. The BISAP score, NLR combined with BISAP score (BN score), PLR combined with BISAP score (BP score), and NLR, PLR combined with BISAP score (BNP score) were compared respectively to predict SAP in patients with HTGP.Results:A total of 82 patients were collected. There were significant differences in the proportion of patients with fever, NLR, PLR, lactate dehydrogenase, urea nitrogen, Ranson score, acute physiology and chronic health evaluationⅡ(APACHEⅡ) score and BISAP score between the two groups (all P<0.05). Logistic regression analysis showed that NLR ( OR=1.859, 95% CI: 1.385-2.497, P<0.001), PLR ( OR=1.074, 95% CI: 1.036-1.112, P<0.001) and BISAP score ( OR=2.880, 95% CI: 1.578-5.258, P=0.001) were risk factors for severe HTGP. Correlation analysis confirmed that NLR and PLR were positively correlated with BISAP, APACHE Ⅱand Ranson score. The AUC of BISAP score, BN score, BP score and BNP score for predicting SAP in HTGP were 0.865 (95% CI: 0.787-0.943), 0.925 (95% CI: 0.869-0.981),0.930 (95% CI: 0.885-0.987), and 0.936 (95% CI: 0.874-0.986). Conclusions:NLR and PLR combined with BISAP score has a higher sensitivity to predict the severity of HTGP, which can predict severe pancreatitis within 24 h of the onset of HTGP, so that providing better guidance for treatment.

Objective:To investigate the prognostic value of platelet volume indices (PVIs), neutrophil/lymphocyte ratio (NLR) and the combination of these parameters for the neurological function of acute ischemic stroke (AIS) patients after intravenous thrombolysis.Methods:From January 2016 to January 2019, the data of 147 AIS patients with intravenous thrombolysis in the Emergency Department of Peking University People's Hospital who met the diagnostic criteria of AIS were retrospectively analyzed. The patients were divided into two groups according to modified rank in scale (MRS) score: MRS≤2 and MRS≥3. The general information, past medical history and laboratory examination results of each group were compared. Logistic regression analysis was used to analyze the risk factors of poor prognosis of neurological function in AIS patients with thrombolysis.Results:NLR ( OR=1.045, 95% CI: 1.032-2.350, P=0.032), mean platelet volume (MPV) ( OR=4.212, 95% CI:1.074-16.513, P=0.039), MPV×NLR/PLT ( OR=5.711, 95% CI: 1.342-24.298, P=0.018), platelet distribution width (PDW) ( OR=1.015, 95% CI: 1.001-2.372, P=0.032), and NIHSS score ( OR=1.266, 95% CI: 1.111-1.443, P<0.01) were related with poor prognosis neurological function of AIS patients with intravenous thrombolysis. Conclusions:MPV, NLR, MPV×NLR/PLT PDW and NIHSS scores are the risk factors for poor prognosis of neurological function in AIS patients with thrombolysis. MPV×NLR/PLT can predict the neurological severity of AIS after 3 months.

Objective:To investigate the diagnostic value of synthetic MRI methods in the differentiation of benign and malignant breast lesions.Methods:Clinical and imaging data of 93 breast patients confirmed by pathology in the Second Affifiliated Hospital of Xi′an Jiaotong University from May 2019 to April 2020 were analyzed retrospectively. All patients underwent synthetic MRI technique, and the quantitative parameters of T 1, T 2, and proton density (PD) values were measured. Independent samples t-test and Wilcoxon test were used to compare the differences in clinical and imaging characteristics between the benign and malignant breast lesions. ROC curve was used for the comparison of the diagnostic efficacy of the quantitative parameters in differentiating malignant from benign breast lesions. Results:Of the 93 patients with breast lesions, 62 cases were malignant and 31 cases were benign. The quantitative T 2 values for benign and malignant lesions were 103 (93, 126)ms and 83 (77, 90)ms respectively, and the quantitative PD values were 87.7 (72.7, 96.7)pu and 73.5(63.3, 79.4)pu respectively. There were statistically significant differences between benign and malignant lesion( P<0.05). Taking quantitative T 2 values of 90.5 ms and PD values of 84.8 pu as the cut-off value, the area under the ROC curve in differentiating benign from malignant breast lesions were 0.87 and 0.75, accuracy values were 80.6% and 78.5%, specificity values were 87.1% and 54.8%, sensitivity values were 77.4% and 90.3% respectively. Conclusion:Synthetic MRI methods can be applied in the examination of breast lesions and has the potential to be an effective diagnostic method for the differential diagnosis between benign and malignant lesions of breast.

Objective:To explore the early prediction value of neutrophil to lymphocyte ratio (NLR) combined with platelet to lymphocyte ratio (PLR) for severe acute pancreatitis (SAP).Methods:A total of 216 patients were collected in the Emergency Department of Peking University People's Hospital who met the diagnostic criteria of acute pancreatitis (AP) from January to December in 2019. Patients were assigned to 3 groups according to the severity of AP: the mild acute pancreatitis group (MAP, n=86), moderately severe acute pancreatitis group (MSAP, n=40), and severe acute pancreatitis group (SAP, n=90). The peripheral blood was taken immediately. White blood cell count (WBC), neutrophil count (NEUT), lymphocyte count (LYM), hemoglobin (HGB), platelet count (PLT), total cholesterol (TC), triglyceride (TG), high-density lipoprotein (HDL), low density lipoprotein (LDL), serum creatinine (CR), and glucose (GLU) were detected. At the same time, CT imaging and other examinations were completed. NLR and PLR were calculated and compared among the three groups. The correlation between NLR, PLR, APACHE II score and Ranson score were compared. The receiver operating characteristic (ROC) curve was drawn to calculate the optimal thresholds of NLR and PLR. NLR-PLR was calculated according to the optimal thresholds of NLR and PLR, and the ROC curve was drawn to study the predictive value of NLR-PLR for SAP. Results:NLR [ OR=1.071, 95% CI (1.025, 1.120), P=0.002] and PLR [ OR=1.003, 95% CI (1.000, 1.244), P=0.044] were risk factors for SAP. NLR was positively correlated with Ranson score ( r=0.0342). NLR was positively correlated with APACHE II score ( r=0.0210). PLR was positively correlated with Ranson score ( r=0.0218, P=0.002). There was no correlation between PLR and APACHE II score ( P=0.157). The areas under the ROC curve (AUC) of NLR and PLR were 0.894 and 0.728. The optimal threshold, sensitivity and specificity of NLR were 6.105, 92.9% and 76.1%, and the optimal threshold, sensitivity and specificity of PLR were 154.358, 78.2% and 73.2%. The AUC of NLR-PLR (0.864) was the largest. Conclusions:NLR and PLR have predictive value for SAP patients within 48 h of the onset of AP. NLR-PLR combined detection have early predictive value for SAP within 48 h of onset.

Objective To investigate the clinical features,diagnosis,treatment and prognosis of 59 patients with thrombotic thrombocytopenic purpura (TTP),therefore to improve the ability of diagnosis and treatment.Methods The clinical data of 59 patients with TTP admitted to Peking University People's Hospital from January 2004 to October 2018 were retrospectively analyzed.All the patients were clinically diagnosed,fulfilled the triad syndrome,or quinary syndrome.Laboratory data included complete blood count,blood biochemistry,immtmology,hemolysis;some patients tested the activity of ADAMTS13.The differences between groups were compared according to the prognosis.Results Among the 59 patients with TTP,21 were male and 38 were female,with an average age of 46.8 years.Fifty-five patients had the triad syndrome and 46 patients had the quinary syndrome.The platelet count and hemoglobin decreased,the percentage of erythrocyte fragmented increased,and the value or the activity of ADAMTS13 was decreased significantly.PLASMIC scores of 57 patients were between 6 and 7.All 59 patients were treated with glucocorticoid,41 patients received plasma exchange (PEX),and 28 patients survived;18 patients did not received PEX,and only 6 patients survived.There was a significant difference of the survival between the two groups (P＜0.05).Six patients were treated with rituximab and four patients survived.Conclusion The PLASMIC score can predict the activity of ADAMTS 13 well.PEX can significantly improve the survival rate of patients with TTP.

Objective:To investigate the clinical characteristics, risk stratification, thrombolytic effects and prognosis of 110 patients with acute pulmonary embolism (PE) treated with thrombolysis.Methods:The clinical data of 110 patients with PE admitted to Beijing University People's Hospital from May 2009 to March 2019 were retrospective analyzed. The clinical data including general information, symptoms and signs, blood pressure, artery blood gas, coaglulation, and radiography were collected. Inclusion criteria: high-risk and intermediate high-risk group. Exclusion criteria: intermediate low-risk and low-risk group. According to the prognosis and risk stratification, the patients were divided into survival group and non-survival group, high-risk group and intermediate high-risk group. The indicators above were compared between with χ 2 test, t test or nonparametric test where appropriate. Results:Of the 110 patients with PE, 49 patients were male and 61 female with an average age of 65±16 years old; and 12 patients were in the high-risk group and 98 in the intermediate high-risk group. The respiratory rate of the high-risk group was higher, and blood pressure, PO 2, SaO 2 before thrombolysis were more lower than the intermediate high-risk group ( P<0.05). One hundred and nine patients were treated with systemic recombinant tissue plasminogen activator (rtPA), 70 patients with 50 mg, and 39 patients with 100 mg. One patient, who was contraindicated to systemic thrombolysis (with active vagina bleeding), was treated with interventional local thrombolysis; another 5 patients treated with interventional local thrombolysis because the clinical symptom were not improved markedly. One hundred and two patients survived and 8 patients died, among which, 3 patients were in the high-risk group and 5 in the intermediate high-risk group. The age, heart rate, respiration rate of the non-survival group were higher than those in the survival group, and the PO 2 before thrombolysis, PCO 2 after thrombolysis were lower ( P<0.05). Bleeding complication were occurred in 22 patients: 18 patients with minor bleeding, such as bleeding gums, skin ecchymosis, and 4 patients with moderate-severe bleeding, such as cerebral hemorrhage, abdominal bleeding, gastrointestinal bleeding, and vagina bleeding. Thirteen of 70 patients in the 50 mg group and 9 of 39 patients in the 100 mg group occurred bleeding complication. The bleeding complication of the low dose group was lower than that of the standard dose group ( P<0.05). Conclusions:Thrombolysis is first-line therapy to high-risk PE. Thrombolysis is safe and effective in the intermediate high-risk group with a lower incidence rate of bleeding complication.