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We have isolated and characterized auxotrophic mutants of Trichosporon adeninovorans, strain PAR-4 to get genetic markers that cover the entire nuclear genome of this thermotolerant yeast of technological interest. The nitrosoguanidine mutagenesis yielded mutants at a high frequency. We detected a broad spectrum of auxotrophic phenotypes in the random mutant samples. Obviously, strain PAR-4 is a haploid or hyperhaploid yeast. In correspondence we determined a low DNA content per cell. In contrast to NG1), UV light was an inefficient mutagen. UV survival curves were without the typical shoulder indicating suppression of repair of UV-induced lethal lesions. Thus, the response of PAR-4 to UV was different from those of Saccharomyces cerevisiae and other yeasts.  相似文献   
977.
The influence of the predictive adaptability on saccades was studied in 20 normal subjects ranging in age from 18 to 43 years. The average velocity of random and constant saccades showed almost the same results. The maximum velocity of constant saccades was slightly faster than that of the random saccades. The latency of the random saccades was shorter than that of the constant ones. Thus, the predictive adaptability of the stimuli has little influence on the maximum velocity and on the latency of saccades in normal subjects.  相似文献   
978.
The aim of this study was to ascertain the prevalence of alternative medicine consumption in Chinese cancer patients on active conventional treatment. A cross sectional survey of 100 consecutive advanced cancer patients admitted to a cancer clinical trial referral unit were personally interviewed by their assigned oncology research nurse using a specially designed questionnaire. The results showed that 64% of our patients used indigenous Chinese medication. In all age groups except the over-70s (P = 0.043), > 50% took such medication, more female (76%) than male (57.6%) patients (P = 0.323). Patients of all educational levels (P = 0.062) and religious backgrounds (P = 0.08) consumed alternative medicines. Duration of alternative medication consumption was less than three months in 50% of patients, with costs between US$40 and 2000/month for 70% of patients. Reasons cited for alternative medication consumption was hope that it might be of some benefit to their well being or disease control, and maybe even result in a miracle cure. Sources of advice on medication were mostly from strangers (by word of mouth), family, friends, the media, and infrequently from qualified professional Chinese doctors. Reasons for discontinuing such treatment were mostly given as lack of positive effect. In conclusion, Chinese cancer patients, willingly, rampantly and non-selectively seek out and consume alternative medications, with almost total ignorance of the medication consumed, oblivious to any potential side effects, and with little subjective benefit.   相似文献   
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980.
Magnetic resonance imaging was performed in 400 patients with degenerative disc disease. Signal changes and their sites in the vertebral body were classified and referred to narrowing of the intervertebral disc space. MR findings were compared with those of plain roentgenograms of the lumbar spine. Signal changes in the vertebral body were noted in 83 cases (102 vertebral bodies). Low-intensity abnormality on both T1- and T2-weighted images (WI) was the most common finding, and was most frequently seen at the end plate and/or the angle. These changes were correlated with narrowing of the disc space and osteosclerosis on the plain roentgenogram of the lumbar spine. Signal changes occasionally occurred in the inner region of the vertebral body, and these lesions tended to show a high-intensity abnormality on T1-WI. We conclude that signal changes in degenerative disc disease are not specific, but are sometimes difficult to distinguish from the signal changes in other conditions such as spinal tumor or bone marrow disorder.  相似文献   
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