Quench of magnetic resonance imaging system refers to the process that the superconducting condition inside the magnet is destroyed due to some reason. The large current stored in the coil is quickly converted into heat at the place where the resistance is formed, and a large amount of liquid helium in the magnet is evaporated. If it happens, it will cause huge loss to the user. We introduce the real cases of 1.5 T magnetic resonance imaging system's quench fault, maintenance treatment and management improvement, which can be used for reference by various medical institutions, so as to better strengthen the operation and maintenance management of magnetic resonance imaging system, so as to avoid the occurrence of out of tolerance fault, and do a good job in the guarantee work after the out of tolerance fault.
Helium ; Magnetic Resonance Imaging ; Magnets

OBJECTIVETo explore the underwater decompression schedule for 100 m Trimix conventional diving operations and evaluate its safety through a simulated rabbits Trimix conventional diving.

METHODSAccording to the Haldane theory, the assumed time units, the classification of tissue compartments, the nitrogen super-saturation safety coefficient and the selection of methods used for the calculation of the simulated 100 m Trimix conventional diving schedule were properly selected, and the calculating method for the dive decompression schedule was thus firmly established. In our experiments, five tissue compartments were selected during the calculation of decompression schedule: 5 min, 10 min, 20 min, 40 min and 75 min, and the nitrogen super-saturation safety coefficient was calculated by 1.6. Eight New Zealand rabbits were performed a simulated 100 m Trimix dive program which was established according to the Haldane theory, and eight rabbits for intact group. The tissues wet/dry ratio and ethology were detected and observed before and after the simulated diving to evaluate the safety of decompression schedule.

RESULTSBy using the developed underwater decompression schedule, abnormal ethology changes in rabbits could not be observed after compression and decompression to the surface; and the tissues wet/dry ratio of simulated diving rabbits had no significant changes compared with the intact group (P > 0.05).

CONCLUSIONThe decompression schedule calculated by Haldane theory seemed to be safe and reliable, the diving breathing gas concentration did not cause oxygen toxicity and nitrogen narcosis among the dive rabbits, and dive efficiency was greatly improved by using enriched oxygen gas in UPTD safety range during decompression.

BACKGROUND AND OBJECTIVES: The development of saturation diving has enabled men to work underseas at great depths and for long periods of time. However, the utilization of HeO2 gas mixture has been a aubject of much study. This paper present a discussion effect of the helium gas on speech by usling gas machine which have been developed. MATERIALS AND METHODS: Twenty male volunteers without voice problems produced /a/ vowel sound before and after helium gas inhalation. The results were analyzed by using an aerophone, an acoustic analyzer, videostroboscopy, and a nasometer. RESULTS: The first formant, the second formant and the bandwidths of the second formant were significantly increased after helium gas inhalation. A meaningful change was noted in asalance. CONCLUSION: The helium gas has an effect on the resonant structure of oral and nasal cavity due to its physical characteristics.
Acoustics ; Diving ; Helium* ; Humans ; Inhalation ; Male ; Nasal Cavity ; Voice ; Volunteers

Since the book "Final Exit: The Practicalities of Self-Deliverance and Assisted Suicide for the Dying" was published in 1991, there has been a worldwide increase in the number of cases of suicidal asphyxiation using helium gas. However, no domestic reports have been published thus far. Recently, we encountered a case of asphyxial suicide by inhalation of helium from inside a plastic bag. Subsequently, we reviewed the records of the Scientific Crime Analysis System of National Police Agency of Korea. There were 17 cases of helium-associated asphyxial suicides between January 1, 2000 and June 30, 2012. The average age of the deceased was 30.6 years with a male to female ratio of approximately 5:1. Thirteen of 17 such deaths occurred in the victims'houses. In all cases, the method of death involved placing a plastic bag over the head with a hose attached to helium tanks. In 6 of 17 cases, the decedents had psychiatric disorders such as depression. As neither characteristic signs of death nor conventional methods for detecting helium gas exist, a thorough investigation of the death scene and the decedents'environment is extremely vital for confirming death due to helium asphyxiation.
Crime ; Depression ; Female ; Head ; Helium ; Humans ; Inhalation ; Korea ; Male ; Plastics ; Police ; Suicide ; Suicide, Assisted

PURPOSE: Intracaverous injections (ICI) are the standard treatment for erectile dysfunction (ED) when oral phosphodiesterase 5 inhibitors (PDE5I) fail or are contraindicated. However, many patients are wary of ICI because of aversion to the injection. We assessed patients' satisfaction and the quality of the sex life in patients undergoing long-term ICI with trimix. MATERIALS AND METHODS: One hundred five patients with ED who had used ICI with trimix for at least 6 months were enrolled in the study. We investigated the Erectile Dysfunction Inventory of Treatment Satisfaction Questionnaire (EDITS), quality of sex life, and pain on injection and erection. The EDITS questions were scored on a 0 to 4-point scale and the mean scores were multiplied by 25 to normalize the scores to a 100-point scale and to create the EDITS index. A total score > 50 was defined as "satisfied with treatment" and a score of < 50 was defined as "not satisfied with treatment." RESULTS: The mean age of the patients was 70+/-8.2 years, the mean duration of ED was 6.4+/-3.3 years, and the mean duration of ICI treatment was 50.3+/-32.6 months. Of the 105 patients, 48.5% had received PDE5I treatment prior to ICI treatment. Among the 51 patients who had received PDE5I, 72.5% (37/51) and 19.6% (10/51) discontinued PDE5I due to inefficacy and side effects, respectively. Four patients used PDE5I in combination with ICI. The mean number of injections was 2.99+/-1.26 per month and the mean dose of trimix was 0.33+/-0.14 ml per injection. The mean EDITS index was 73.7+/-14.5, and 93% of the patients were classified in the satisfaction group according to the EDITS index criteria. Patients noted an improvement in their sex life (78.1%), their relationship with their partner (68.6%), and their quality of life (65.7%) after using ICI with trimix; 92.3% of patients responded that they were ready to recommend ICI with trimix to their friends. The mean scores for pain on injection and erection were 1.04/10 and 0.98/10, respectively. CONCLUSIONS: In spite of long-term treatment, ICI with trimix met the expectations of patients. ICI with trimix is revealed as easy, effective, and tolerable treatment. ICI with trimix should be positively recommended when PDE5I fails or is contraindicated.
Erectile Dysfunction ; Friends ; Helium ; Humans ; Male ; Nitrogen ; Oxygen ; Phosphodiesterase 5 Inhibitors ; Quality of Life

Every operation could have a fire emergency, especially in the case of a tracheostomy. When a flammable gas meets a source of heat, the danger of fire is remarkable. A tracheal tube filled with a high concentration of oxygen is also a great risk factor for fire. Intra-tracheal tube fire is a rare, yet critical emergency with catastrophic consequences. Thus, numerous precautions are taken during a tracheostomy like, use of a special tube to prevent laser damage, ballooning of the tube with normal saline instead of air, and dilution of FiO2 with helium or nitrogen. Since the first recorded cases on tube fires, most of the fires were initiated in the balloon and the tip. In the present case report, however, we came across a fire incidence, which originated from the wire.
Airway Management ; Burns ; Emergencies ; Fires ; Helium ; Hot Temperature ; Incidence ; Nitrogen ; Oxygen ; Porphyrins ; Risk Factors ; Tracheostomy

BACKGROUND: Recently it has been suggested that lasers can modulate the biological functions of cells in vitro. It has also been reported that a helium-neon(He-Ne) laser can stimulate wound healing in the absence of thermal effects. However, the results of more recent studies on the influence of He-Ne laser irradiation on the proliferation and collagen synthesis of human dermal fibroblasts have been inconclusive. And most experiments have not been performed in a three-dimensional collagen lattice that is the physiologic model for an in vitro experiment. OBJECITVE: In this study we have investigated the nature of the influence of He-Ne laser irradiation on the proliferatior and collagen synthesis of human dermal fibroblasts cultured in a monolayer and collagen lattice. METHODS: We used a 10mW He-Ne laser emitting a beam of wavelength 632,8nm. The human dermal fibroblasts were subjected to laser treatment at various energy densities, and the treatment schedule included one daily exposure on three consecutive days. DNA replication was assessed by H-thymidine incorporation, and the collagen production was monitored by the synthesis of H-hydroxyproline following incubation of the culture with H-proline. RESULTS: The results were as follows : In the control group, the proliferation and collagen synthesis of fibroblasts sultured in a collagen lattice on day 4 and 7 were significantly reduced compared with conventional manolayer cultures. Although the proliferation of human dermal fibroblasts was not remarkable in all experimental irradiation energy except 4 J/cm in a monolayer culture, a statistically significant stimulating effect on fibroblasts proliferation in collagen lattice were noted on days 4 and 7 with an energy density of 1.5J/cm. And we also found that a great er increase of collagen synthesis of human dermal fibroblasts occurred in a monolayer culture on days 4 and 7 in all irradiated energy densities than those in a collagen lattice culture. But statistically significant enhancement of collagen synthesis was showed only at the energy density of 1 J/cm in a collagen lattice culture on days 4. CONCLUSION: These data indicated that the influence of He-Ne laser irradiation on the proliferation and collagen synthesis of human dermal fibroblasts cultured in a collagen lattice was remark ably different from those in a monolayer culture. In the clinical application of the He-Ne laser, the control of the amount of irradiation of the He Ne laser may regulate the proliferative activity and collagen synthesis of human dermal fibroblasts in wound healing.
Appointments and Schedules ; Collagen* ; DNA Replication ; Fibroblasts* ; Helium* ; Humans* ; Neon* ; Wound Healing

BACKGROUND: Recently it has been suggested that lasers can modulate the biological functions of cells in vitro. It has also been reported that a helium-neon(He-Ne) laser can stimulate wound healing in the absence of thermal effects. However, the results of more recent studies on the influence of He-Ne laser irradiation on the proliferation and collagen synthesis of human dermal fibroblasts have been inconclusive. And most experiments have not been performed in a three-dimensional collagen lattice that is the physiologic model for an in vitro experiment. OBJECTIVE: In this study we have investigated the nature of the influence of He-Ne laser irradiation on the proliferatior and collagen synthesis of human dermal fibroblasts cultured in a monolayer and collagen lattice. METHODS: We used a 10mW He-Ne laser emitting a beam of wavelength 632,8nm. The human dermal fibroblasts were subjected to laser treatment at various energy densities, and the treatment schedule included one daily exposure on three consecutive days. DNA replication was assessed by H-thymidine incorporation, and the collagen production was monitored by the synthesis of H-hydroxyproline following incubation of the culture with H-proline. RESULTS: The results were as follows : In the control group, the proliferation and collagen synthesis of fibroblasts sultured in a collagen lattice on day 4 and 7 were significantly reduced compared with conventional manolayer cultures. Although the proliferation of human dermal fibroblasts was not remarkable in all experimental irradiation energy except 4 J/cm in a monolayer culture, a statistically significant stimulating effect on fibroblasts proliferation in collagen lattice were noted on days 4 and 7 with an energy density of 1.5J/cm. And we also found that a great er increase of collagen synthesis of human dermal fibroblasts occurred in a monolayer culture on days 4 and 7 in all irradiated energy densities than those in a collagen lattice culture. But statistically significant enhancement of collagen synthesis was showed only at the energy density of 1 J/cm in a collagen lattice culture on days 4. CONCLUSION: These data indicated that the influence of He-Ne laser irradiation on the proliferation and collagen synthesis of human dermal fibroblasts cultured in a collagen lattice was remark ably different from those in a monolayer culture. In the clinical application of the He-Ne laser, the control of the amount of irradiation of the He Ne laser may regulate the proliferative activity and collagen synthesis of human dermal fibroblasts in wound healing.
Appointments and Schedules ; Collagen* ; DNA Replication ; Fibroblasts* ; Helium* ; Humans* ; Neon* ; Wound Healing

BACKGROUND: Recently it has been suggested that lasers can modulate the biological functions of cells in vitro. It has also been reported that a helium-neon(He-Ne) laser can stimulate wound healing in the absence of thermal effects. However, the results of more recent studies on the influence of He-Ne laser irradiation on the proliferation and collagen synthesis of human dermal fibroblasts have been inconclusive. And most experiments have not been performed in a three-dimensional collagen lattice that is the physiologic model for an in vitro experiment. OBJECITVE: In this study we have investigated the nature of the influence of He-Ne laser irradiation on the proliferatior and collagen synthesis of human dermal fibroblasts cultured in a monolayer and collagen lattice. METHODS: We used a 10mW He-Ne laser emitting a beam of wavelength 632,8nm. The human dermal fibroblasts were subjected to laser treatment at various energy densities, and the treatment schedule included one daily exposure on three consecutive days. DNA replication was assessed by H-thymidine incorporation, and the collagen production was monitored by the synthesis of H-hydroxyproline following incubation of the culture with H-proline. RESULTS: The results were as follows : In the control group, the proliferation and collagen synthesis of fibroblasts sultured in a collagen lattice on day 4 and 7 were significantly reduced compared with conventional manolayer cultures. Although the proliferation of human dermal fibroblasts was not remarkable in all experimental irradiation energy except 4 J/cm in a monolayer culture, a statistically significant stimulating effect on fibroblasts proliferation in collagen lattice were noted on days 4 and 7 with an energy density of 1.5J/cm. And we also found that a great er increase of collagen synthesis of human dermal fibroblasts occurred in a monolayer culture on days 4 and 7 in all irradiated energy densities than those in a collagen lattice culture. But statistically significant enhancement of collagen synthesis was showed only at the energy density of 1 J/cm in a collagen lattice culture on days 4. CONCLUSION: These data indicated that the influence of He-Ne laser irradiation on the proliferation and collagen synthesis of human dermal fibroblasts cultured in a collagen lattice was remark ably different from those in a monolayer culture. In the clinical application of the He-Ne laser, the control of the amount of irradiation of the He Ne laser may regulate the proliferative activity and collagen synthesis of human dermal fibroblasts in wound healing.
Appointments and Schedules ; Collagen* ; DNA Replication ; Fibroblasts* ; Helium* ; Humans* ; Neon* ; Wound Healing

BACKGROUND: Recently it has been suggested that lasers can modulate the biological functions of cells in vitro. It has also been reported that a helium-neon(He-Ne) laser can stimulate wound healing in the absence of thermal effects. However, the results of more recent studies on the influence of He-Ne laser irradiation on the proliferation and collagen synthesis of human dermal fibroblasts have been inconclusive. And most experiments have not been performed in a three-dimensional collagen lattice that is the physiologic model for an in vitro experiment. OBJECTIVE: In this study we have investigated the nature of the influence of He-Ne laser irradiation on the proliferatior and collagen synthesis of human dermal fibroblasts cultured in a monolayer and collagen lattice. METHODS: We used a 10mW He-Ne laser emitting a beam of wavelength 632,8nm. The human dermal fibroblasts were subjected to laser treatment at various energy densities, and the treatment schedule included one daily exposure on three consecutive days. DNA replication was assessed by H-thymidine incorporation, and the collagen production was monitored by the synthesis of H-hydroxyproline following incubation of the culture with H-proline. RESULTS: The results were as follows : In the control group, the proliferation and collagen synthesis of fibroblasts sultured in a collagen lattice on day 4 and 7 were significantly reduced compared with conventional manolayer cultures. Although the proliferation of human dermal fibroblasts was not remarkable in all experimental irradiation energy except 4 J/cm in a monolayer culture, a statistically significant stimulating effect on fibroblasts proliferation in collagen lattice were noted on days 4 and 7 with an energy density of 1.5J/cm. And we also found that a great er increase of collagen synthesis of human dermal fibroblasts occurred in a monolayer culture on days 4 and 7 in all irradiated energy densities than those in a collagen lattice culture. But statistically significant enhancement of collagen synthesis was showed only at the energy density of 1 J/cm in a collagen lattice culture on days 4. CONCLUSION: These data indicated that the influence of He-Ne laser irradiation on the proliferation and collagen synthesis of human dermal fibroblasts cultured in a collagen lattice was remark ably different from those in a monolayer culture. In the clinical application of the He-Ne laser, the control of the amount of irradiation of the He Ne laser may regulate the proliferative activity and collagen synthesis of human dermal fibroblasts in wound healing.
Appointments and Schedules ; Collagen* ; DNA Replication ; Fibroblasts* ; Helium* ; Humans* ; Neon* ; Wound Healing