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Ralls PW; Johnson MB; Kanel G; Dobalian DM; Colletti PM; Boswell WD Jr; Radin DR; Halls JM 《Radiology》1986,161(2):451-454
FM sonography - a signal-processing technique that uses frequency and phase information as well as amplitude data - shows promise in evaluation of patients with diffuse liver disease. In a prospective blinded review of 37 patients with biopsy-proved liver disease and 42 healthy volunteers, FM sonography was clearly superior to traditional amplitude-based (AM) sonography in distinguishing healthy from diseased subjects. Statistically significant differences were seen in accuracy (FM, 98.7%; AM, 84.8%), sensitivity (FM, 97.3%; AM, 70.3%), and negative predictive value (FM, 97.7%; AM, 78.8%). Our data also suggest that current FM sonographic techniques cannot differentiate among histologic findings associated with different hepatic parenchymal abnormalities. It is unclear, therefore, whether FM imaging can reduce the numbers of patients who require biopsy for diagnosis or the frequency of biopsy procedures in patients with known disease. 相似文献
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A R Wright P T English H M Cameron J B Wilsdon 《Acta radiologica (Stockholm, Sweden : 1987)》1992,33(6):582-587
Pelvimetry remains a useful technique as part of the assessment of the term breech pregnancy where vaginal delivery is planned. MR pelvimetry is accurate, well tolerated and shows soft-tissue structures as well as bone. It avoids the potentially carcinogenic effects of ionising radiation and is thought to be completely safe for mother and fetus. A technique of MR pelvimetry is described which uses gradient-echo sequences. This quick, practical method makes minimal inroads into valuable scanning time, and may therefore be considered a potentially cost-effective alternative to conventional pelvimetry. 相似文献
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Yoshimitsu Kuroyanagi DR. ENG DR. SCI DR. MED ; Akihiko Shiraishi MD ; Yoshiteru Shirasaki MD ; Nobuaki Nakakita MD ; Yoshiaki Yasutomi MD ; Yasuo Takano MD ; Nobuyuki Shioya MD FACS 《Wound repair and regeneration》1994,2(2):122-129
A bilaminar wound dressing composed of an outer membrane and an inner three-dimensional matrix of a fabric or a sponge may be considered to constitute an ideal structure that promotes wound healing: the outer membrane prevents body fluid loss, controls water evaporation, and protects the wound surface from bacterial invasion, and the inner matrix encourages adherence by tissue growth into the matrix. Using this concept, we developed a biosynthetic wound dressing with a drug delivery capability. This medicated wound dressing is composed of a spongy sheet of a chitosane derivative and collagen mixture that is laminated to an antimicrobial-impregnated polyurethane membrane. In this study, a gentamycin sulfate-impregnated wound dressing was prepared and evaluated. The antimicrobial efficacy of this wound dressing was examined on an agar plate seeded with Pseudomonas aeruginosa. Also, the cytotoxicity of an antimicrobial released from this wound dressing was examined in an in vitro system with cultured skin substitutes. Both in vitro tests have shown that this wound dressing is capable of suppressing bacterial growth and minimizing cellular damage. In addition, in the treatment of wounds inflicted on rats and rabbits, this wound dressing was shown to be efficacious in covering full-thickness and split-thickness skin defects. Finally, the efficacy of this wound dressing was evaluated in a nonrandomized open-label study of 31 clinical cases. In 31 cases treated with this wound dressing, good or excellent wound healing was achieved. 相似文献
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DR Foster 《Journal of Medical Imaging and Radiation Oncology》1995,39(4):399-400
The use of self-expanding prostheses in the management of malignant oesophageal strictures has become well established. The majority of benign peptic oesophageal strictures can be successfully managed using endoscopic or fluoroscopically guided balloon oesophageal dilatation combined with long-term drug therapy, particularly using proton pumper inhibitors. Although endoscopic oesophageal dilatation can be performed on an outpatient basis, it requires repeated hospital visits. There is a small risk of oesophageal perforation whilst cardio-respiratory complications may be encountered during the use of intravenous sedation in an elderly population. The use of a self-expanding Strecker stent in a 98 year old woman with a benign oesophageal stricture is described. 相似文献
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Hemodynamic characteristics, arrhythmogenicity, and dose-related hemodynamic responses to intravenous dopamine (group I) and dobutamine (group II) were examined in 16 swine at three different core body temperatures (38.5 degrees C, 35 degrees C, and 30 degrees C). The animals were anesthetized with isoflurane and mechanically ventilated. Cooling and re-warming were accomplished by a femoral-jugular A-V shunt. The animals were cooled down to 30 degrees C and stabilized for 1 hour before intravenous infusion of dopamine (group I, n = 8) or dobutamine (group II, n = 8) was started at 2, 5, 10, 15, 20, and 30 micrograms/kg/min. Hemodynamic responses to the two inotropes were continuously monitored with a bedside monitor equipped with a PC mode for customized data collection and analysis. Computerized arrhythmia detection was performed. Our findings were: (1) profound hypothermia (30 degrees C) causes significant depression of hemodynamic functions; (2) IV infusion of dopamine and dobutamine can be used safely and effectively for inotropic support during profound hypothermia, and the optimal dosage for improving cardiac output is 10-20 micrograms/kg/min; (3) no risk of inducing arrhythmia was noted with IV infusion of both inotropes up to a maximum dosage of 30 micrograms/kg/min, even though significant sinus tachycardia was consistently seen at 30 micrograms/kg/min. 相似文献
20.
Cardiac surgery for patients aged 65 years and older: a long term survival analysis. 总被引:1,自引:1,他引:0 下载免费PDF全文
S Livesey N Caine D J Spiegelhalter T A English J Wallwork 《Heart (British Cardiac Society)》1988,60(6):480-484
Between January 1973 and December 1984, 562 patients aged greater than or equal to 65 had cardiac surgery at Papworth Hospital. Most had mitral or aortic valve replacements (coronary artery bypass grafting was not introduced for this age group at Papworth until 1977). The overall operative mortality, defined as death within thirty days or death before leaving hospital, was 7.3%. There were no early deaths in patients undergoing coronary artery bypass grafting surgery. Questionnaires sent to general practitioners in East Anglia traced 86.0% of the patients who survived to leave hospital. The longer term survival rates for all patients were 88.0%. (95% confidence interval (CI) 85 to 91) at one year and 74.4% (95% CI 69 to 79) at five years. The rates for those patients who survived the initial few months were 96.3% (95% CI 94 to 98) at one year and 81.5% (95% CI 77 to 86) at five years and these rates were no different from those in the general population aged greater than or equal to 65. 相似文献