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排序方式: 共有995条查询结果,搜索用时 15 毫秒
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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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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
5.
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
6.
Treatment of severe craniocerebral traumas in medium and major hospitals not provided with special neurosurgical equipment requires particularly close interdisciplinary cooperation between surgeons, neurologists and anaesthesiologists. CT facilities are an essential prerequisite for best possible patient care. Patient safety during the posttraumatic and postoperative phases is improved by measuring the intracranial pressure. Whereas corticosteroid treatment may be arguable, barbiturate treatment should presently not be a routine procedure because of its side effects and high rate of complications. 相似文献
7.
Joey C Eisenmann Peter T Katzmarzyk Louis Perusse Claude Bouchard Robert M Malina 《The Journal of adolescent health》2003,33(3):147-153
PURPOSE: To examine the association between estimated daily energy expenditure and blood lipids in a sample of adolescents. METHODS: The sample consisted of 415 males and 356 females aged 10-19 years, mainly French Canadian, recruited from the greater Quebec City area through the media as part of Phase I of the Quebec Family Study. Estimates of daily energy expenditure (DEE) were obtained with a 3-day physical activity record. Blood lipids were measured by standard procedures. The sample was stratified into three activity groups (least active, less than 25th percentile of DEE; moderately active, 25-74th percentile of DEE; and most active, 75th percentile or greater of DEE), and also by clinical cutpoints for blood lipids. Analysis of covariance, controlling for age and fatness, was conducted to compare blood lipids within gender across activity groups. Logistic regression analysis, controlling for age and fatness, was used to estimate the relative risk of being classified with an undesirable level of a blood lipid parameter on the basis of the DEE. RESULTS: Total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) levels were not significantly different across activity groups in males or females. High-density lipoprotein cholesterol (HDL-C) was significantly different across activity groups in males (p <.05) and females (p <.05), but the pattern of variation was different between genders. In males, the TC/HDL-C and LDL-C/HDL-C ratios decreased between the moderately active and most active groups (p <.05). Significant differences remained when subcutaneous fatness was considered as a covariate. The results from logistic regression analysis indicated that the odds ratios for low HDL-C levels was significant only in low DEE girls (odds ratio 2.83) compared with high DEE girls. CONCLUSIONS: The results suggest that increased energy expenditure and physical activity are associated with higher levels of HDL-C in adolescents of both sexes. 相似文献
8.
In 260 asbestos-exposed individuals evaluated by means of computed tomography (CT), 43 unsuspected pulmonary masses were found in 27 individuals. The masses included fissural pleural plaques (n = 10), dense fibrotic bands (n = 3), round atelectasis (n = 11), carcinomas (n = 3), and other presumed benign masses (n = 16). The most helpful features in the diagnosis of rounded atelectasis with CT were (a) contiguity to areas of diffuse pleural thickening, (b) a lentiform or wedge-shaped outline, (c) evidence of volume loss in the adjacent lung, and (d) a characteristic "comet tail" of vessels and bronchi sweeping into the margins of the mass. Less advanced areas of focal atelectasis had fewer classic features. Intrafissural pleural plaques were readily identified with high-resolution CT. In asbestos-related masses, the demonstration of stability over time is necessary. Careful interpretation of CT and high-resolution CT features and close surveillance can obviate the need for biopsy in the majority of instances. 相似文献
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The intercellular adhesion molecule (ICAM) family of proteins 总被引:8,自引:0,他引:8
Macromolecular adhesive associations between cells are important for transmitting spatial and temporal information that is
critical for immune system function. One such group of proteins, the intercellular adhesion molecules (ICAMs), has grown as
newly identified members are revealed. In addition, the functions of the ICAMs, in general, have begun to be better understood,
including intracellular signaling events. This information has led to the design of novel therapeutic agents that may prove
effective in a variety of disease states. 相似文献