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71.
72.
Bone marrow disorders: characterization with quantitative MR imaging   总被引:10,自引:0,他引:10  
Smith  SR; Williams  CE; Davies  JM; Edwards  RH 《Radiology》1989,172(3):805-810
Thirty patients with various hematologic disorders and 15 healthy control subjects underwent quantitative magnetic resonance (MR) imaging of the lumbar spine with spin-echo techniques. Images of patients with infiltrative bone marrow disorders showed significantly more prolonged T1 times than those of control subjects (P less than .001). It was not possible to distinguish different diffuse infiltrative bone marrow disorders on the basis of T1 values. Aplastic anemia could be distinguished from normality because of significantly shortened T1 (P less than .001). A significant correlation was seen between T1 and bone marrow cellularity (r = .74, P less than .001). T2 was of no value in the characterization of bone marrow disorders. Quantitative MR imaging dose not improve the diagnostic potential of bone marrow imaging in the detection of diffuse marrow infiltrates.  相似文献   
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74.
The elbow: MR features of nerve disorders   总被引:3,自引:0,他引:3  
  相似文献   
75.
We have reviewed the demographic characteristics of, and report abnormalities noted in, the de-novo growth and development of a paid oocyte donation programme. The personal profiles of all prospective oocyte donors were reviewed. Acceptance or rejection of candidates was based upon screening the results of medical, genetic and psychological testing. A total of 603 candidates initially responded to our advertisement. From this pool, 313 individuals were considered suitable and contacted by telephone. Following further conversation, 176 women were scheduled an entry interview. On completion of the formal screening process, 17.6% (n = 31) of those actually interviewed were denied entry. Thus, from the initial interested parties, only 23% of women wishing to participate in oocyte donation were considered suitable candidates. Given the high attrition rate, we concluded that the need for rigorous and thorough medical, psychological and genetic testing is mandatory for the establishment of a donor registry. Furthermore, professional counselling of prospective donors with respect to the results of tests and the implications of test results with respect to their future medical and reproductive health, are important parts of providing comprehensive care.   相似文献   
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77.
BACKGROUND.: The effectiveness of health promotion activity in general practiceon risk factor reduction for coronary heart disease remainsthe subject of active debate. OBJECTIVE.: The study aimed to assess the impact of practice-based healthcheck-ups on health behaviours over a 2-year period. METHOD.: A general practice cohort of 7123 patients from 18 practiceswas surveyed. Eight hundred and forty (12%) patients had beenoffered a heafth check within a 12-month period from September1992 and 621 (9%) received one. Two hundred and fifty patients(40%) were asked back for follow-up after their health check. RESULTS.: Over a 2-year period there was no difference in smoking cessation,alcohol consumption, weight loss nor the amount of exercisetaken between those who attended for a health check and thosewho did not. The food score chosen to assess dietary change(Oxcheck) showed a statistically significant 1.16-point risefor the whole sample over the survey period. There was a significantdifference in mean food score change between heafth check attendersand non-attenders (Mann-Whitney U test: P << 0.002). Maintenanceof dietary improvement over a 2-year period was not affectedby health check attendance. CONCLUSIONS.: This study confirms the low impact of health checks on the selfreported modification of cardiovascular risk factors and showsthat maintenance of appropriate health behaviour change is nomore likely in those who have received a health check. Keywords. Health promotion, general practice.  相似文献   
78.
79.
Acoustic analysis of gradient-coil noise in MR imaging   总被引:4,自引:0,他引:4  
Hurwitz  R; Lane  SR; Bell  RA; Brant-Zawadzki  MN 《Radiology》1989,173(2):545-548
A survey was conducted of acoustic noise levels in magnetic resonance (MR) imaging systems. Static magnetic flux and radio-frequency pulses did not affect the function of shielded sound-pressure detection equipment. Noise levels were measured at bore isocenter during a variety of imaging sequences in six MR imaging systems with magnetic fields of 0.35-1.5 T. Measured noise ranged from 82 to 93 dB on the A-weighted scale and from 84 to 103 dB on the linear scale. Noise levels increased during sequences employing thinner section thickness and shorter repetition and echo times and were independent of field strength. Gradient-coil noise in MR imaging is an annoyance but is well within safety guidelines.  相似文献   
80.
Maloney  JJ; Cho  SR 《Radiology》1983,148(2):388
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