Development of rapid decompression equipment ejected by air pressure in low-pressure chamber / 医疗卫生装备

Objective To develop a kind of rapid decompression equipment replacing the toughened glass simulating the state of aircraft cabin glass bursting on the fly.Methods The metallic membrane was used to isolate both chambers with different air pressures.The areas of decompression membrane and path were determined by calculating on the basis of aircraft decompression altitude,cabin pressure differential and decompression time.The structural strength was determined according to enduring force of the metallic membrane.The membrane was ejected by high pressure air using the ejection launch technology of aircraft missile.The result of simulating aircraft cabin glass bursting on the fly was achieved.Results The rapid decompression equipment ejected by air pressure in low-pressure chamber could achieve the state of simulating aircraft cabin glass bursting on the fly,and the best decompression time was 0.16 s.Conclusion The rapid decompression equipment ejected by air pressure accomplishes the decompression preparative in short time with easy operation,and can satisfy the desired requirements for the performance and precision.

Compound effects of inhaling pure oxygen and lifting height on ear baric function in a hypobaric chamber / 解放军医学杂志

Objective To compare the ear baric function between 4000m altitude chamber test with inhaling air and 6900m altitude chamber test with inhaling pure oxygen.Methods Eleven healthy male volunteers attended two tests as two groups by self-comparison. As the air group the volunteers inhaled air at 4000m, while as the pure oxygen group they inhaled pure oxygen at 6900m altitude, and the time interval between the two tests was more than two weeks. During the test, the volunteers breathed air or pure oxygen at random for 1h, and then were exposed at a speed of 20m/s to the target altitude for 5min. Hereafter they were sent back to the ground at the same speed. The changes of subjective symptoms, degree of tympanic congestion, acoustic immitance index and pure-tone auditory threshold were recorded before and after the test. The acoustic impedance index and pure-tone threshold were statistically analyzed.ResultsFour volunteers (4 ears) in air group and 7 volunteers (7 ears) in pure oxygen group reported ear pain in altitude chamber exposures, respectively. The pain-triggering altitude was higher in the pure oxygen group. Immediately after tests, there were 3 (3 ears) and 5 volunteers (5 ears) with Ⅲ degree congestion of the tympanic membrane in the two groups respectively. Four volunteers (6 ears) developed gradually aggravated hemorrhages after altitude exposure. And the tympanic membrane congestion difference between groups was statistically significant at 3 and 24h after tests (P<0.01). The type A tympanogram appeared in 11 (15 ears) and 11 (14 ears) volunteers respectively immediately after tests. The increase of static compliance value was significantly greater in pure oxygen group than in air group immediately after tests (P<0.05), the decrease of middle ear pressure was more significant in pure oxygen group than in air group at 3 and 24h after tests (P<0.05). Both the two altitude exposure tests resulted in eustachian tube dysfunction. At 3 and 24h after the tests, the increase of individual frequency pure-tone threshold was significantly higher in pure oxygen group than in air group (P<0.05).Conclusion Breathing pure oxygen and lifting height could increase the screening degree of ear baric function test in hypobaric chamber, and have greater influence on degree of tympanic congestion, acoustic immittance and pure-tone auditory threshold in 24 hours.

Application of three-dimensional printed skull in the teaching of human anatomy / 基础医学与临床

Objective This experiment aimed to find out the feasibility of applying 3D printing technology to anato-my education. Methods We constructed 3D printed skull using a cadaveric skull as template.26 participants were recruited from Peking Union Medical College. All participants studied cranial anatomy with 3D printed skulls as teaching materials,and then assessed practicability of 3D printed skulls by subjective assessment questionnaires. Results 57% participants considered that 3D printed skulls can present defined cranial anatomical structures.More than 90% participants agreed that 3D printed models helped spatial comprehension and study of anatomy.88% par-ticipants suggested 3D printing can solve the problem of ethics.84% participants agreed to apply 3D printed models into cranial anatomy education. Conclusions The efficacy of 3D printing had been confirmed in anatomical educa-tion. Further application of 3D printing technology in medical education needs carrying out.

Study on survival status and pathogens in adult patients with severe community-acquired pneumonia for the past ten years / 天津医药

Objective To investigate the survival status and pathogens in adult patients with severe community-acquired pneumonia (SCAP) for the past ten years in our hospital. Methods A total of 159 adult patients with SCAP were enrolled for this study from January 2007 to December 2016 in our hospital. Patients were divided into early stage group (from January 2007 to December 2011, n=71) and late stage group (from January 2012 to December 2016, n=88). The clinical data, pathogen distribution and prognosis were compared between two groups. Results (1) The proportion of patients with blood urea nitrogen (BUN) > 7.1 mmol/L was significantly higher in late stage group than that of early stage group (P<0.05). There were no significant differences in baseline data, vital signs, imaging findings and other laboratory examinations between the two groups (P>0.05). (2) For distribution of pathogens, 42 and 49 cases were detected pathogens in early stage group and late stage group. The detection rate of Legionella pneumophila was significantly higher in late stage group than that in early stage group (26.5% vs. 7.1%, P<0.05). (3) For complications, the incidence of septic shock was significantly higher in late stage group than that in the early stage group (22.7%vs. 9.9%, P<0.05). The fatality rate within 30 d after admission was significantly higher in late stage group than that of early stage group (43.2%vs. 25.4%, P<0.05). Results of multi-factor Cox proportional hazard regression analysis showed that septic shock and respiratory acidosis were independent risk factors of mortality in early stage group (P<0.05) while septic shock, chronic obstructive pulmonary disease (COPD) and multi-lobar infiltrates were independent risk factors of mortality in late stage group ( P<0.05). Conclusion In the past ten years, basic clinical characteristics of adult patients with SCAP in our hospital have changed little, but detection rate of legionella has showed increasing trend, and the short-term mortality rate has increased. Whether or not patients are combined with septic shock is a key factor affecting the prognosis.

Application of three-dimensional printed skull in the teaching of human anatomy / 基础医学与临床

Objective This experiment aimed to find out the feasibility of applying 3D printing technology to anato-my education. Methods We constructed 3D printed skull using a cadaveric skull as template.26 participants were recruited from Peking Union Medical College. All participants studied cranial anatomy with 3D printed skulls as teaching materials,and then assessed practicability of 3D printed skulls by subjective assessment questionnaires. Results 57% participants considered that 3D printed skulls can present defined cranial anatomical structures.More than 90% participants agreed that 3D printed models helped spatial comprehension and study of anatomy.88% par-ticipants suggested 3D printing can solve the problem of ethics.84% participants agreed to apply 3D printed models into cranial anatomy education. Conclusions The efficacy of 3D printing had been confirmed in anatomical educa-tion. Further application of 3D printing technology in medical education needs carrying out.

Study on survival status and pathogens in adult patients with severe community-acquired pneumonia for the past ten years / 天津医药

Objective To investigate the survival status and pathogens in adult patients with severe community-acquired pneumonia (SCAP) for the past ten years in our hospital. Methods A total of 159 adult patients with SCAP were enrolled for this study from January 2007 to December 2016 in our hospital. Patients were divided into early stage group (from January 2007 to December 2011, n=71) and late stage group (from January 2012 to December 2016, n=88). The clinical data, pathogen distribution and prognosis were compared between two groups. Results (1) The proportion of patients with blood urea nitrogen (BUN) > 7.1 mmol/L was significantly higher in late stage group than that of early stage group (P<0.05). There were no significant differences in baseline data, vital signs, imaging findings and other laboratory examinations between the two groups (P>0.05). (2) For distribution of pathogens, 42 and 49 cases were detected pathogens in early stage group and late stage group. The detection rate of Legionella pneumophila was significantly higher in late stage group than that in early stage group (26.5% vs. 7.1%, P<0.05). (3) For complications, the incidence of septic shock was significantly higher in late stage group than that in the early stage group (22.7%vs. 9.9%, P<0.05). The fatality rate within 30 d after admission was significantly higher in late stage group than that of early stage group (43.2%vs. 25.4%, P<0.05). Results of multi-factor Cox proportional hazard regression analysis showed that septic shock and respiratory acidosis were independent risk factors of mortality in early stage group (P<0.05) while septic shock, chronic obstructive pulmonary disease (COPD) and multi-lobar infiltrates were independent risk factors of mortality in late stage group ( P<0.05). Conclusion In the past ten years, basic clinical characteristics of adult patients with SCAP in our hospital have changed little, but detection rate of legionella has showed increasing trend, and the short-term mortality rate has increased. Whether or not patients are combined with septic shock is a key factor affecting the prognosis.

The denitrogenation by breathing oxygen-rich gas to prevent altitude decompression sickness / 中国应用生理学杂志

<p><b>OBJECTIVE</b>While the technology of the molecular sieve oxygen generation system(MSOGS) onboard was used, pilots could not breathe pure oxygen to eliminate nitrogen during a high altitude flight. There is no report whether it is a threat to altitude decompression sickness(ADS) or not in that condition. This experiment was intended to observe the effects of breathing different oxygen-rich gases of MSOGS on denitrogenation, so that we could make the medical physiological requirements for MSOGS on-board and provide experimental basis for aeromedical supply.</p><p><b>METHOD</b>Eight healthy males were breathed oxygen-rich gases (60%,70%,80%,90%and 99.6%) in turn for 60 min, and the concentration of nitrogen, oxygen, carbon dioxide and argon at the end of expiration interval in the oxygen mask were continuously measured by a flight mass spectrometer through the oxygen mask. According to the variety of the denitrogenation rate by breathing different oxygen-rich gases, its change law was analyzed.</p><p><b>RESULTS</b>There were significant differences (P < 0.05) about denitrogenation rate in different oxygen-rich gases due to different oxygen concentration and breathing time. The denitrogenation rate of pure oxygen was higher than that of the others. It was indicated that the concentration of nitrogen in lung would decrease along with the increase in oxygen concentration of oxygen-rich gases, and the nitrogen concentration in the lung almost decreased by 50% or even more if people were breathed 60%-90% oxygen-rich gas longer than 60 s.</p><p><b>CONCLUSION</b>The man-made respiration environment of low nitrogen can be provided by breathing oxygen-rich gases, although the denitrogenation velocity of breathing oxygen-rich gases is lower than that of breathing pure oxygen. So it can be used as a measure to eliminate and lower the nitrogen in the body to prevent from ADS.</p>

Effect of interleukin-10 on experimental severe acute pancreatitis's histopathologic score in rats / 中国康复理论与实践

@#ObjectiveTo explore effect of interleukin-10 (IL-10) on histopathologic scores of severe acute pancreatitis (SAP) and the level of serum amylase (AMY) in rats.Methods48 female and male adult Sprague Dawley rats (200—300g) were randomly allocated into three groups: OPgroup, SAP group and IL-10 group with 16 rats in each group. SAP was made with retrograde ductal infusion of 5% sodium taurocholate solution.ResultsIn SAP and IL-10 group, there were interstitial edema, necrosis, neutrophil infiltration and interstitial hemorrhage of pancreas, more or less. At 6h and 12h after models were made, the pancreatic histopathologic score in IL-10 group (4.00±0.33 and 6.25±0.25) were significantly lower than that in SAP group (6.13±0.35 and 9.50±0.50)(P<0.01). At 6 h after models were made, the serum AMY in IL-10 group was lower than that in SAP group (P<0.05), but at 12 h there were no differences.ConclusionIn earlier period of SAP in rats, IL-10 can lower the serum AMY level, and significantly reduced pancreatic histologic score (edema, inflammation, hemorrhage, and necrosis).

Development of Parameter Measuring System for Oxygen Supply Unit in Lowpressure Chamber / 医疗卫生装备

Objective To develop the measuring system used for the parameters of onboard oxygen supply equipment in the hypobaric chamber. Methods The programmable controller was applied to acquisition, processing and analysis of the data from the sensor. The host computer was used to accomplish control and information display. Results The system could display the parameters through digital, simulating meters, and recording curve. The numerical value in the recording curve was marked by the date and time. All data were saved in the computer for futural analysis and procession. Conclusion The measurement system of oxygen supply parameters can satisfy the desired requirements for the performance and precision.