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The objective of this study was to evaluate fast and ultrafast T2-weighted images (T2WI), including echo planar imaging (EPI), using an AMI-25 agar phantom. Image quality for conventional spin echo (CSE) and turbo spin echo (TSE) was almost equivalent. In high-resolution TSE, image quality was highest due to the use of a 512 x 256 matrix. Half-Fourier single-shot turbo SE (HASTE) was associated with blurring of images, and turbo-gradient SE (TGSE) showed a deterioration of image quality. EPI also suffered from poor image quality because this method is very sensitive to magnetic field inhomogeneity. CSE showed good signal-to-noise ratio (S/N) and contrast ratio (CR), but also required the longest imaging times. Among the TSE sequences, TSE with a short echo train length (ETL) was superior in terms of S/N. The CR of EPI and fast low angle shot (FLASH) images were improved in proportion to the effective echo time (TE). At present, TSE is inferior to CSE in terms of S/N and CR. However, taking into consideration scanning time, TSE with a short ETL is thought to be suitable for routine examinations. Effective TE is an important factor in gradient echo (GRE) examinations.</P>

Thirteen previously untreated patients aged 70 and above with acute nonlymphocytic leukemia were treated with aclarubicin (ACR) alone. Among 10 cases (3, acute myelocytic leukemia; 4, acute myelomonocytic leukemia; 2, acute monocytic leukemia; and one, acute erythroleukemia) in which an evaluation was possible, 5 cases (3, acute myelomonocytic leukemia; and 2, acute monocytic leukemia) obtained complete remission (CR). The CR rate was 83% in 6 patients with acute myelomonocytic leukemia or acute monocytic leukemia. The median CR duration and survival was 7.5 and 10 + months, respectively. Although side effects of the drug on digestive system such as nausea, vomiting and anorexia were observed in all patients, they were controllable by conventional treatments. The results suggest that ACR is effective for the clinical management of elderly patients with acute nonlymphocytic leukemia, especially those with acute myelomonocytic leukemia or acute monocytic leukemia.

The relationship between past and present lifestyle and urinary excretion of type I collagen cross-linked N-telopeptides (NTx) was studied in 61 Japanese females aged 34-59, with a view toward using NTx excretion rates as a predictor of future osteoporosis. Bone mineral density (BMD) of the lumbar spine, the speed of sound (SOS) and broadband ultrasound attenuation (BUA) of the os calcis, urinary NTx, serum osteocalcin (BGP) and bone-specific alkaline phosphatase (BAP) were measured. Stiffness index (stiffness) was calculated from SOS and BUA. The subjects were asked whether they took regular exercise in their childhood and teen years (in elementary, junior-high, senior-high school and college), the past (20-40 years of age) and present adulthood. Regular calcium intake, smoking habits, alcohol and other beverage consumption and milk consumption were also covered in the questionnaire. The mean NTx values of premenopausal and postmenopausal group were 22.2 and 56.0 nM bone collagen equivalents (BCE)/mM urinary creatinine (Cr), respectively. The group which did not exercise regularly between the ages of 20 and 40 had a higher mean NTx value (40.9 nMBCE/mMCr) than the group which did exercise regularly (22.7 nMBCE/mMCr). In multiple regression analyses, age, stiffness and exercise in past adulthood could explain 43.5% of the NTx variance. For prevention of bone metabolic increases around menopause, habitual exercise in early adulthood seems to be effective.

Today Vitallium is used for surgical implants. It is a casting alloy which, with advances in casting technology, is also used commercially for making instruments of fairly complex shape. Because of its expense, however, it is not widely used in Japan. Instead, a series of 18-8 Mo alloys are used in Japan even though of insufficient strength. Used over a long period of time in the body, especially for the purpose of preserving structual functions as part of the human skeleton, it often corrodes, resulting in either abnormalities in tissue cells or, because of its insufficient strength, danger of bending and breaking with aging. In spite of a marked advance in fracture treatment, we have hardly any suitable materials for making instruments appropriate to the internal fixation of fractures in Japan. We, therefore, conducted various experiments to develop an alloy with sufficient corrosive resistance and strength that could be formed into a complex shape to take the place of Vitallium alloy, finally succeeding in developing an alloy we call "COP". The characteristic properties of COP may be summarized as follows: 1. The main components are 20% Cr, 20% Ni, 20% Co and 4% Mo aside from 0.2% P. 2. As it contains "P", it shows a marked age-hardening. In its molten state its machinability is excellent, and later it can readily be hardened by heat-treatment. 3. It has not only a marked yield point and tensile strength but also has toughness in elongation and reduction of area, showing a strength which surpasses Vitallium. 4. Its corrosive resistance is great. 5. Its cost is far cheaper than Vitallium.