• Title/Summary/Keyword: Injury data

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The Occurrence of Rice Leaf-folder, Cnaphalocrocis medinalis (Lepidoptera : Crambidae) in Suwon and its Responses to Insecticides (혹명나방 개체군의 수원지역 발생 패턴 및 몇가지 약제에 대한 반응)

  • Park, Hong-Hyun;Cho, Jum-Rae;Park, Chang-Gyu;Kim, Kwang-Ho;Goh, Hyun-Gwan;Lee, Sang-Guei
    • Korean journal of applied entomology
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    • v.49 no.3
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    • pp.219-226
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    • 2010
  • This paper presents the occurrence and damage characteristics of the rice leaf-folder populations in the paddy fields of Dangsu-dong, Suwon from 2004 to 2007, and also reports the insecticide response of rice leaf-folder populations, which were collected from 2005 to 2006 in Korea and Vietnam. Laboratory measurements of the head capsule width and body length data enabled the identification of the rice leaf-folder larva stages collected in the field. The rice leaf-folder population in Suwon from 2004 to 2007 has a clear pattern consisting of two different group: the low and high density years. During the low density years (2004 and 2006), only one adult peak was noted in late August, with the damaged-hill percent less than 10% in late July, and the damaged-leaf percent around 2% in September. In contrast, during the high density years (2005 and 2007), two adult peaks were noted in early August and mid-September, with the damaged-hill percent was around 30% in late July, and the damaged-leaf percent 15 to 30% in September, which was beyond the economic injury level of rice leaf-folder. High correlations existed between the occurrence of rice leaf-folder in late July and early August and damages to rice during September. Based on these results, we suggest that the information on the rice leaf-folder population monitored by the adult density or damaged-hill percent in late July and early August would be very useful for predicting the damages later in the season for aiding in decision-making for timely control. In addition, the regional populations of rice leaf-folder showed the similar responses to the insecticides tested: high susceptibility to IGRs (tebufenozide and methoxyfenozide) and organophosphates (chlorpyrifos-methyl, pyridaphenthion), but relatively low to cartap.

in vitro and in vivo Photodynamic Activity Study of U-87 Human Glioma Cell with Photofrin (실험관 및 생체내에서 U-87 교모세포종 세포주의 광역학 치료 효과에 대한 연구)

  • Cho, Woo Jin;Cho, Kyung-Keun;Ji, Cheol;Park, Sung Chan;Park, Hea Kwan;Kang, Joon Ki;Choi, Chang Rak
    • Journal of Korean Neurosurgical Society
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    • v.30 no.5
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    • pp.553-560
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    • 2001
  • Objective : The objective of this study was to determine the photodynamic therapeutic response of U-87 human glioma cell in vitro as well as in the nude rat xenograft model using photofrin as photosensitizer. Material and Method : U-87 cells were cultured on 96-well culture plates, photofrin(Quadralogic Technologies Inc., Vancouver, Canada) was added into the cell culture medium at concentration of $1{\mu}g/ml$, $2.5{\mu}g/ml$, $5{\mu}g/ml$, $10{\mu}g/ml$ and $20{\mu}g/ml$. 24 hour after drug treatment, cells were treated with optical(632nm) irradiation of $100mJ/cm^2$, $200mJ/cm^2$ and $400mJ/cm^2$. Photofrin(12.5mg/kg, i.p.) was administered to 28 nude rats containing intracerebral U-87 human glioma as well as 26 normal nude rats. 48 hours after administration, animals were treated with optical irradiation(632nm) of $35J/cm^2$, $140J/cm^2$ and $280J/cm^2$ to exposed tumor and normal brain. The photofrin concentration was measured in tumor and normal brain in a separate population of animals. Results : By MTT assay, there was 100% cytotoxicity at any dose of photofrin with optical irradiation of $200mJ/cm^2$ and $400mJ/cm^2$. But at the optical irradiation of $100mJ/cm^2$ cells were killed in dose dependent manner 28.5%, 49.1%, 54.4%, 78.2%, and 84.6% at concentration of $1{\mu}g/ml$, $2.5{\mu}g/ml$, $5{\mu}g/ml$, $10{\mu}g/ml$ and $20{\mu}g/ml$, respectively. Dose dependent PDT lesions in both tumor and normal brain were observed. In the tumor lesion, only superficial tissue damage was found with optical irradiation of $35J/cm^2$. However, in the optical irradiation group of $140J/cm^2$ and $280J/cm^2$ the volume of lesions was measured of $7.2mm^3$ and $14.0mm^3$ for treatment at $140J/cm^2$ and $280J/cm^2$, respectively. The U-87 bearing rats showed a photofrin concentration in tumor tissue of $6.53{\pm}2.16{\mu}g/g$, 23 times higher than that found in the contralateral hemisphere of $0.28{\pm}0.15{\mu}g/g$. Conclusion : Our data indicate that the U-87 human glioma in vitro and in the xenografted rats is responsive to PDT. At these doses, a reproducible injury can be delivered to human glioma in this model. Strategies to spare the normal brain collateral damage are being studied.

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Functional recovery after transplantation of mouse bone marrow-derived mesenchymal stem cells for hypoxic-ischemic brain injury in immature rats (저산소 허혈 뇌 손상을 유발시킨 미성숙 흰쥐에서 마우스 골수 기원 중간엽 줄기 세포 이식 후 기능 회복)

  • Choi, Wooksun;Shin, Hye Kyung;Eun, So-Hee;Kang, Hoon Chul;Park, Sung Won;Yoo, Kee Hwan;Hong, Young Sook;Lee, Joo Won;Eun, Baik-Lin
    • Clinical and Experimental Pediatrics
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    • v.52 no.7
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    • pp.824-831
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    • 2009
  • Purpose : We aimed to investigate the efficacy of and functional recovery after intracerebral transplantation of different doses of mouse mesenchymal stem cells (mMSCs) in immature rat brain with hypoxic-ischemic encephalopathy (HIE). Methods : Postnatal 7-days-old Sprague-Dawley rats, which had undergone unilateral HI operation, were given stereotaxic intracerebral injections of either vehicle or mMSCs and then tested for locomotory activity in the 2nd, 4th, 6th, and 8th week of the stem cell injection. In the 8th week, Morris water maze test was performed to evaluate the learning and memory dysfunction for a week. Results : In the open field test, no differences were observed in the total distance/the total duration (F=0.412, P=0.745) among the 4 study groups. In the invisible-platform Morris water maze test, significant differences were observed in escape latency (F=380.319, P<0.01) among the 4 groups. The escape latency in the control group significantly differed from that in the high-dose mMSC and/or sham group on training days 2-5 (Scheffe's test, P<0.05) and became prominent with time progression (F=6.034, P<0.01). In spatial probe trial and visible-platform Morris water maze test, no significant improvement was observed in the rats that had undergone transplantation. Conclusion : Although the rats that received a high dose of mMSCs showed significant recovery in the learning-related behavioral test only, our data support that mMSCs may be used as a valuable source to improve outcome in HIE. Further study is necessary to identify the optimal dose that shows maximal efficacy for HIE treatment.

Opelative Risk and Results of Reoporation for Heart Valve Prostheses (인공심장판막 재치환술에 대한 수술 위험 인자 및 결과)

  • 김철환;김경훈
    • Journal of Chest Surgery
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    • v.30 no.10
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    • pp.973-978
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    • 1997
  • We reviewed data of 64 patients who underwent reoperation because of prosthetic valve malfunction from January 1991 to December 1995. The indications for reoperation were prosthetic valve failure(primary tissue failure: 53 patients, 82.8%), prosthetic valve thrombosis(6 patients, 9.4%), paravalvular leak(3 patients, 4.7%), prosthetic valve endocarditis(2 patients, 3.6%). Prosthetic valve failure developed most frequently in mitral portion(40 patients, 75%), prosthetic valve thrombosis also in mitral portion(4 patients, 67%), paravalvular leak significantly in aortic portio (3 patients, 100%). Explant period was longest in prosthetic valve failure(mean 107.4 $\pm$ 24.6 months), shortest in prosthetic valve endocarditis with prosthetic valve thrombosis(1 patient, 1 month). Mean explant period, defined as from first valve replacement operation to redo-valve replacement operatopn, was 109.2$\pm$ 10.7 months in mitral portion, 97.8$\pm$ 10.4 months in aortic portion, 109.5$\pm$ 10.4 months in total. Overall hospital mortality was 9.38%. The most common cause of death was the low cardiac output(4 patients), other causes were bleeding(1 patient), CNS injury(1 patient). Preoperative NYHA class IV(P=0.011), emergency operation(P=0.011), prosthetic valve endocarditis(P=0.001) were the independent risk factors, but age, sex, explant period, ACC time, double valve replacement, valve position, second reoperation did not appear to be significant risk factors. Mean follow up period was 28.8 $\pm$ 17.8 months. Actuarial survival at 3 year was 92.0$\pm$6.2%, 2 year event-free survival w s 84.3$\pm$6.1%. We propose that patients undergoing reoperation because of prosthetic valve failure are carfully controlled and selected in regarding to above mentioned risk factors NYHA class IV, emergency operation, prosthetic valve endocarditis in preoperative state. About other risk factors possible, there is necessary of following study.

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A Study of Aortic Vasculopathy after Cardiac Allograft (동종 심장이식 후의 대동맥 혈관병증에 관한 연구)

  • Chung, Won-Sang;Chung, Yoon-Sang;Kim, Young-Hak;Kim, Hyuck;Kang, Jeong-Ho;Paik, Seung-Sam;Song, Dong-Seop;Jang, Hyo-Jun
    • Journal of Chest Surgery
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    • v.42 no.2
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    • pp.135-140
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    • 2009
  • Background: Chronic rejection after a cardiac allograft usually occurs about six months after the operation. Vasculopathy due to chronic rejection causes atherosclerosis in the coronary artery of the transplanted heart and then this causes myocardial injury. We intended to discover and document those findings that occur in a transplanted ascending aorta. Material and Method: In rats weighting $200{\sim}300gm$ (Spraque-Dawley rat), we carried out heterotopic heart allo-transplantation with the modified Ono-Lindsey method and then the rats were administrated cyclosporine (10mg/kg/day). After three months survival, we acquired biopsy materials from the native ascending aorta and the allo-transplanted ascending aorta and we compared them. We classified each severity of 1) intimal thickening, 2) medial hyperplasia, 3) medial calcification, 4) medial inflammation and 5) chondroid metaplasia, which are specific biopsy findings for chronic rejection after a cardiac allograft. Each severity was classified, according to the opinion of one pathologist, in the native ascending aorta biopsies (n=9) and the allo-transplanted ascending aorta biopsies (n=13). The data of the control group and the study group were statistically analyzed with using the Mann-Whitney test (SPSS version 12.0 window). Result: The important changes of the allo-transplanted aorta were intimal thickening (p<0.0001), medial calcification (p=0.045), medial inflammation (p<0.0001) and chondroid metaplasia (p=0.045), but not medial hyperplasia (p=0.36). Conclusion: Cardiac allograft vasculopathy was seen in the transplanted ascending aorta, the same as was seen in the coronary artery, after allograft cardiac transplantation. We have reached the conclusion that chronic rejection also progresses in the aorta.

The Effect of a Chest CT Scan on the Treatment and Diagnosis of Major Blunt Chest Trauma (흉부 둔상환자에서 흉부전산화단층촬영이 진단과 치료에 미치는 영향)

  • Park, Il-Hwan;Oh, Joong-Hwan;Lee, Chong-Kook
    • Journal of Chest Surgery
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    • v.42 no.2
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    • pp.226-232
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    • 2009
  • Background: Blunt chest trauma accounts for 90% of all chest traumas in Europe and the United States and this causes 20% of all trauma-related deaths. The major cause of morbidity and mortality after blunt chest trauma is undetected injuries. For this reason, chest computerized tomography has gained popularity for the evaluation of trauma, but it is expensive and it exposes patients to radiation. This study identified the clinical features associated with the diagnosic information obtained on a CT chest scan, as compared with a standard chest X-ray, for patients who sustained blunt trauma to the chest. This study also evaluated the role of a routine computed tomographic (CT) scan for these patients. The patients who had chest computed tomography done after the initial chest x-ray were analyzed separately for the presence of occult injuries. Material and Method: We studied 100 consecutive patients from November 2006 to July 2007: 74 patients after motor vehicle crashes and 26 patients after a fall from a height >2m. Simultaneous with the initial clinical evaluation, an anteroposterior chest radiograph and a helical chest CT scan were obtained for all the patients. The data extracted from the medical record included the vital signs, the interventions and the type and severity of injury (RTS). Result: Among the 100 cases, 79 patients showed at least more than one pathologic sign on their chest radiograph, and 21 patients had a normal chest radiograph. For 17 of the patients who had a normal chest X ray, the CT scan showed multiple injuries, which were pneumothorax, hemothorax, lung contusion, sternal fracture etc. This represents that a CT scan is statistically superior to a chest radiograph to diagnose the pathologic signs. But on the other hand, as for treatment, only 31 patients were diagnosed by CT scan and they were treated with chest tube insertion ect. 42 patients needed ony conservative management without invasive thoracosurgical treatment such as chest tube insertion or open thoracotomy. 27 patients were treated based on the diagnosis made by the chest radiograph and physical examination. Conclusion: Chest computerized tomography was significantly more effective than routine chest X-ray for detecting lung contusion, pneumothorax and mediastinal hematoma, as well as fractured ribs, scapula and, sternum. Although the occult findings increased, the number of patients who needed treatment was small. Therefore, we suggest making selective use of a CT scan to avoid its overuse in ERs.

Stress Perception, Stress Response and Coping Strategy of Patients with Chronic Prostatitis (만성전립선염 환자들의 스트레스 지각, 스트레스 반응 및 대처방식)

  • Kim, Sun-Kyung;Lee, Jin;Jeong, Seong-Yun;Kim, Hack-Ryul;Park, Sang-Hag;Lee, Moon-In;Kim, Sang-Hoon
    • Korean Journal of Psychosomatic Medicine
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    • v.17 no.1
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    • pp.8-14
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    • 2009
  • Objectives : The purpose of this study was to investigate the various aspects of stress in patients with chronic prostatitis. Methods : Thirty two chronic prostatitis patients meeting the criteria of NIH-category III were compared with sixty four controls. Data pertaining to the source of, response to, and coping with stress, as well as chronic prostatitis symptom index were collected using a self-report questionnaire. The questionnaire consisted of a Global Assessment of Recent Stress(GARS), Stress Response Inventory(SRI), Ways of Coping Checklist(WCC), in addition to the NIH-CPSI. Results : From the results of GARS subscales, the scores of changes in relationship, sickness or injury and financial were significantly higher in patients with chronic prostatitis than normal controls. Chronic prostatitis patients had greater amplification of somatization, depression and anger in SRI and significantly lower score in ways of coping checklist compared with controls. In the NIH-CPSI of chronic prostatitis patients, the degree of symptom played a role in depression as stress response item and significant negative correlationship between the symptom point and problem focused, seeking social support coping strategy was observed. Conclusion : These results show that patients with chronic prostatitis have greater stress, higher stress response and insufficient coping strategy. Therefore, these efforts should be considered that enhancing healthier coping strategy and evaluation and management of stress experienced by chronic protatitis patients

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The Factors Related to Musculoskeletal Symptoms of Family Care-Givers who Have a Patient with Brain Damage (뇌손상 가족 간병인의 근골격계 자각증상과 관련요인)

  • Jeon, Eun-Mi;Lee, Seong-A;Gu, Jung-Whan
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.1
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    • pp.336-344
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    • 2017
  • This study was conducted to identify factors related to the musculoskeletal symptoms of 340 family caregivers who have a patient with brain damage based on self-administered questionnaires. The questionnaires included general characteristics, characteristics of care activities and caregivers' musculoskeletal symptoms. Data were collected from many long-term care hospitals and rehabilitation centers during March 17 to March 21, 2014. The results indicated that complaint rates of work-related musculoskeletal systems of the body sites differed. Factor analysis revealed that neck complaints were related to education (under mid), while shoulder complaints were related to sex (female), age (50-59), education (mid) and duration of care (< 2 years). Arm/elbow complaints were related to age (40-49), education (high) and duration of care (12-24). Complaints regarding the hand/wrist/finger were related to age (50-59) and duration of care (12-24), while those associated with the legs/feet were related to age (50-59) and duration of care (< 6[ED highlight - years? Please specify.]). Back problems were related to education (under mid, mid stage, high) and gait. The complaint rate regarding musculoskeletal symptoms during daily life was not statistically significant. Logistic regression analysis of significant factors related to subjective musculoskeletal symptoms identified ambulation and gait as having the greatest influence and complaint factor among family caregivers. The complaint rate of family caregivers differed among body parts. Being a caregiver for less than one year was found to have a significant impact on pain. Overall, long term family caregivers could be faced with risk factors for musculoskeletal problems, but there are many different factors that affect musculoskeletal symptoms with regards to their activities. Accordingly, comprehensive and systematic prevention plans for family caregivers who have patients with brain damage should be developed.

A Study on the Demand for Equipent Development in Nursing (간호기기 개발수요 조사연구)

  • Chang, Soon-Book;Kim, Eui-Sook;Whang, Ae-Ran;Kang, Kyu-Sook;Suh, Mi-Hae
    • The Korean Nurse
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    • v.35 no.2
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    • pp.71-91
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    • 1996
  • The objectives of thes study were to identify the need for equipment development in nursing, and to determine the priorities for that development. The study was descriptive study done between March 2 and May 30, 1995, in which the subjects, including 421 patients, 223 family members, and 198 nurses from neurosurgery, orthopedic, rehabilitation medicine, internal medicine and intensive care units of nine general hospitals in Seoul, completed a questionnarie developed by the research team. The questionnaire consisted of 35 open and closed questions. Data was analyzed using frequencies and percentages. The results ware summarized as follows: 1) The average age of the nurses was 27.9 years, 48% of the patients were between 20 and 40 years of age, and 17% were over 60. The average lingth of experience for the nurse subjects was four years five months with 36.9%. having over five years experience. The most frequent diagnoses of patients were spinal disc(35.9%), internal medicine disease(26.0%), cerebral vascular accident(16.6%) and spinal cord injury(10%) 2) Many of the nurses(96.4%) reported deficiencies with existing equipment and 96.5% of the nurses, but only 79.8% of the patients, nurses' time. Further, 82.3% of the nurses and 75.8% of the patients felt that the development of new equipment would lead to a decrease in the cost of nursing care. 3) Nurses felt that the greatest areas of inconvenience were patient feeding(71.7%), hygiene(71.2%), caring for a patient confined to bed(70.7%), patient clothing(67.2%), mobility transfers(63.5%) and urinary elimination(52.0%). However, patients and family members listed the following as being the most inconvenient: urinary elimination(58.7%), Hygiene(50.5), feeding(48.4%), mobility transfers(47.1%) and bed care(45.2%). 4) Generally the nurses listed more inconveniences and patients and family members listed more demands for the development of equipment. These included utensils with large handles, and regulators for tube feedings; mattresses that provide for automatic position change and massage, which have patient controlled levers and a place for bed pan insertion; automatic lifts or transfer from bed to wheelchair; equipment to facilitate washing and oral hygiene as well as equipment that will allow patients with spinal cord injuries easy access to showers; a bed pan/urinal for women that is comfortable and effective from which urine can be measured and disposed of easily; disposable dressing sets and tracheostomy care sets and a convenient way of measuring changes in wound size; a safe delivery system for oxygen, a variety of mask sizes and better control of humidity, tracheal material than at present, as well as a communication system for patients with tracheostomies; clothing that will allow access to various parts of the body for treament or assessment without patients having to remove all of their clothing; and finally a system that will allow the patient to control lighting, telephones and pagers. Priority areas for equipment development reported by the nurses were, urinary elimination(58. 7%), hygiene(50.5%), feeding(48.4%), mobility transfers(47..1%), bowel elimination(40.8%). Those reported by the patients family members were feeding(71.7%), hygiene(70.0%), bedcare(70.7%), clothing(67.2%), mobility transfers(63.6%), urinary elimination(52.9%) and bowel elimination(50.5%) Altogether, nurses, patients and family members listed the following as priorities; clothing (178), bed care(144), urinary elimination(92), environment(81), hygiene(70). Further, a health professional forum listed urinary elimination, oxygen delivery, medication delivery, mobility transfers, bed care and hygiene in that order as priority areas. From this study it can be concluded that the first need is to develop equipment that will address the problems of urinary elimination. To do (l)This nurses who are interested in equipment development should organize an equipment development team to provide a forum for discussion and production of equipment for nursing.

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THE CURRENT STATUS OF BIOMEDICAL ENGINEERING IN THE USA

  • Webster, John G.
    • Proceedings of the KOSOMBE Conference
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    • v.1992 no.05
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    • pp.27-47
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    • 1992
  • Engineers have developed new instruments that aid in diagnosis and therapy Ultrasonic imaging has provided a nondamaging method of imaging internal organs. A complex transducer emits ultrasonic waves at many angles and reconstructs a map of internal anatomy and also velocities of blood in vessels. Fast computed tomography permits reconstruction of the 3-dimensional anatomy and perfusion of the heart at 20-Hz rates. Positron emission tomography uses certain isotopes that produce positrons that react with electrons to simultaneously emit two gamma rays in opposite directions. It locates the region of origin by using a ring of discrete scintillation detectors, each in electronic coincidence with an opposing detector. In magnetic resonance imaging, the patient is placed in a very strong magnetic field. The precessing of the hydrogen atoms is perturbed by an interrogating field to yield two-dimensional images of soft tissue having exceptional clarity. As an alternative to radiology image processing, film archiving, and retrieval, picture archiving and communication systems (PACS) are being implemented. Images from computed radiography, magnetic resonance imaging (MRI), nuclear medicine, and ultrasound are digitized, transmitted, and stored in computers for retrieval at distributed work stations. In electrical impedance tomography, electrodes are placed around the thorax. 50-kHz current is injected between two electrodes and voltages are measured on all other electrodes. A computer processes the data to yield an image of the resistivity of a 2-dimensional slice of the thorax. During fetal monitoring, a corkscrew electrode is screwed into the fetal scalp to measure the fetal electrocardiogram. Correlations with uterine contractions yield information on the status of the fetus during delivery To measure cardiac output by thermodilution, cold saline is injected into the right atrium. A thermistor in the right pulmonary artery yields temperature measurements, from which we can calculate cardiac output. In impedance cardiography, we measure the changes in electrical impedance as the heart ejects blood into the arteries. Motion artifacts are large, so signal averaging is useful during monitoring. An intraarterial blood gas monitoring system permits monitoring in real time. Light is sent down optical fibers inserted into the radial artery, where it is absorbed by dyes, which reemit the light at a different wavelength. The emitted light travels up optical fibers where an external instrument determines O2, CO2, and pH. Therapeutic devices include the electrosurgical unit. A high-frequency electric arc is drawn between the knife and the tissue. The arc cuts and the heat coagulates, thus preventing blood loss. Hyperthermia has demonstrated antitumor effects in patients in whom all conventional modes of therapy have failed. Methods of raising tumor temperature include focused ultrasound, radio-frequency power through needles, or microwaves. When the heart stops pumping, we use the defibrillator to restore normal pumping. A brief, high-current pulse through the heart synchronizes all cardiac fibers to restore normal rhythm. When the cardiac rhythm is too slow, we implant the cardiac pacemaker. An electrode within the heart stimulates the cardiac muscle to contract at the normal rate. When the cardiac valves are narrowed or leak, we implant an artificial valve. Silicone rubber and Teflon are used for biocompatibility. Artificial hearts powered by pneumatic hoses have been implanted in humans. However, the quality of life gradually degrades, and death ensues. When kidney stones develop, lithotripsy is used. A spark creates a pressure wave, which is focused on the stone and fragments it. The pieces pass out normally. When kidneys fail, the blood is cleansed during hemodialysis. Urea passes through a porous membrane to a dialysate bath to lower its concentration in the blood. The blind are able to read by scanning the Optacon with their fingertips. A camera scans letters and converts them to an array of vibrating pins. The deaf are able to hear using a cochlear implant. A microphone detects sound and divides it into frequency bands. 22 electrodes within the cochlea stimulate the acoustic the acoustic nerve to provide sound patterns. For those who have lost muscle function in the limbs, researchers are implanting electrodes to stimulate the muscle. Sensors in the legs and arms feed back signals to a computer that coordinates the stimulators to provide limb motion. For those with high spinal cord injury, a puff and sip switch can control a computer and permit the disabled person operate the computer and communicate with the outside world.

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