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83.
High-resolution MR imaging with local coils 总被引:4,自引:0,他引:4
We propose the following rules to govern the choice of local coils by the practicing radiologist: 1. Smaller coils permit smaller FOVs and better resolution. The coil should be as small as possible. 2. Match the ROS of the coil to the FOV, which will be determined by the anatomic region of interest. 3. For the case of a choice between surface coils or between a surface and a whole- or partial-volume coil, the anatomic region should lie on the high side of the crossover point. For the case of a choice among whole-volume coils, the smallest coil that surrounds the region of interest should be chosen. 4. Considerations in regard to the anatomic shape or the need to vary the position of the structure may alter the choice of coil from that obtained by S/N considerations alone. 相似文献
84.
Cystic fibrosis: current survival and population estimates to the year 2000. 总被引:26,自引:16,他引:10 下载免费PDF全文
BACKGROUND: Survival from cystic fibrosis is increasing rapidly. Estimates of the extent of this improvement should allow health care facilities to be planned to deal with the expanding population of patients with cystic fibrosis. Estimates of life expectancy are also essential if accurate information on current prognosis is to be given to parents of an affected child, or to prospective parents deciding whether to proceed with a pregnancy where the fetus may be affected. METHODS: Survival trends in the national data on cystic fibrosis have been analysed to produce estimates of the likely size of the cystic fibrosis population over the next decade and to predict the life expectancy of children born with cystic fibrosis in the years up to 1990. RESULTS: In England and Wales the estimated number of patients with cystic fibrosis is at present about 5200, of whom 3300 (63%) are aged under 16 years. By the year 2000 the total population will increase to 6000, with 3400 (57%) aged under 16. Thus the number of children with cystic fibrosis will remain fairly constant over the next 10 years, whereas adult numbers will increase by about 36% (from 1901 to 2577). The median life expectancy of children with cystic fibrosis born in 1990 is estimated to be 40 years, double that of 20 years ago. CONCLUSION: This study suggests that health service provision for children will not need to change substantially over the next 10 years whereas services for adults will need to increase by about a third. Parents can be counselled that the median life expectancy of a newborn child with cystic fibrosis is currently likely to be of the order of 40 years. 相似文献
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国产沉香化学成分的研究——Ⅲ.异白木香醇的结构测定和低沸点成分的分离与鉴定 总被引:3,自引:0,他引:3
自国产沉香(Aquilaria sinensis)[瑞香科(Thymeleaceae)植物]的挥发油中,经硅胶柱层析和离心薄层层析分离得到一新的倍半萜,命名为异白木香醇(isobaimuxinol),根据光谱(IR,~1HNMR,~(13)CNMR,2 D-NMR和MS)分析确定其结构式为(Ⅰ)所示,并用X-光衍射晶体解析进一步确定了其立体化学。同时,也从该植物挥发油的低沸点部分分离得到四个已知化合物:苄基丙酮,对甲氧基苄基丙酮,茴香酸和β-沉香呋喃。这些化合物均为首次从该植物中得到。 相似文献
87.
Ryan F Donnelly Paul A McCarron Corona M Cassidy J Stuart Elborn Michael M Tunney 《Journal of controlled release》2007,117(2):217-226
Respiratory disease is the main cause of morbidity and mortality in patients with cystic fibrosis (CF). In such patients chronic Pseudomonas aeruginosa infection is virtually impossible to eradicate using antibiotic therapy. Photodynamic antimicrobial chemotherapy (PACT) could be one potential alternative antimicrobial method. As photosensitisers could be delivered to the lungs of CF patients via inhalation, the current in vitro study investigated the potential use of PACT in the treatment of P. aeruginosa CF pulmonary infection. Delivery of red light (635 nm) and two photosensitisers (toluidine blue O (TBO) and meso-tetra (N-methyl-4-pyridyl) porphine tetra tosylate (TMP)) across artificial CF mucus was successfully achieved. Artificial CF mucus reduced the measured fluence of incident light in an almost exponential manner with increasing depth. The presence of dissolved photosensitisers also reduced light fluence. TMP diffused more efficiently across artificial CF mucus than TBO. However, receiver compartment concentrations of both drugs after 6 h were of the same order as those required to achieve high rates of kill (>99%) of P. aeruginosa isolates growing both planktonically and in biofilms. TMP required significantly higher concentrations (2.5 mg ml(-1)) than TBO to achieve high rates of kill (>99%) of P. aeruginosa isolates growing planktonically. Higher concentrations (5.0 mg ml(-1)) of both photosensitisers were required to achieve high rates of kill (>99%) of P. aeruginosa isolates growing in biofilms. When photosensitisers were prepared in artificial mucus, higher concentrations were required to achieve reasonably high kill rates (>80%) of P. aeruginosa (PAO1) growing both planktonically and in biofilm. 相似文献
88.
Timothy J. Kidd Rafael Canton Miquel Ekkelenkamp Helle Krogh Johansen Peter Gilligan John J. LiPuma Scott C. Bell J. Stuart Elborn Patrick A. Flume Donald R. VanDevanter Valerie J. Waters 《Journal of cystic fibrosis》2018,17(6):696-704
Antimicrobial resistance (AMR) can present significant challenges in the treatment of cystic fibrosis (CF) lung infections. In CF and other chronic diseases, AMR has a different profile and clinical consequences compared to acute infections and this requires different diagnostic and treatment approaches. This review defines AMR, explains how it occurs, describes the methods used to measure AMR as well as their limitations, and concludes with future directions for research and development in the area of AMR in CF. 相似文献
89.
J Punnose MD DM TM Yahya MD JS Premchandran MD HF Ahmed FRCP 《International journal of clinical practice》1997,51(7):468-470
We describe two type 2 diabetic patients with unilateral emphysematous pyelonephritis who responded to medical treatment alone. Escherichia coli was isolated in both patients. The presence of gas was confirmed early by ultrasound and CT scan of abdomen. Following treatment, good functional recovery was demonstrable in the affected kidneys by isotope renogram. We stress the need for early diagnosis of this condition and aggressive treatment with broad spectrum antibiotics. 相似文献
90.
Qiwei Chen Sudha Priya Soundara Pandi Lauren Kerrigan Noel G. McElvaney Catherine M. Greene J. Stuart Elborn Clifford C. Taggart Sinéad Weldon 《Journal of cystic fibrosis》2018,17(5):616-623