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81.
Sch 14342 is an aminoglycoside antibiotic coproduced as a minor component in the gentamicin fermentation. Sch 14342 was found to have the same antibacterial spectrum as gentamicin in vitro and in vivo, and was approximately one-third as active in mouse protection tests. Sch 14342 relative to gentamicin was one-third as toxic in acute tests in mice, one-eighth as toxic in renal toxicity tests in dogs, and an estimated one-tenth as toxic in cat ataxia tests. Sch 14342 possesses a significantly improved therapeutic index relative to gentamicin with reference to ataxia potential and renal toxicity.  相似文献   
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Activated microglia are important pathological features of a variety of neurological diseases, including the normal aging process of the brain. Here, we quantified the level of microglial activation in the aging rhesus monkey using antibodies to HLA-DR and inducible nitric oxide synthase (iNOS). We observed that 3 out of 5 white matter areas but only 1 of 4 cortical gray matter regions examined showed significant increases in two measures of activated microglia with age, indicating that diffuse white matter microglial activation without significant gray matter involvement occurs with age. Substantial levels of iNOS and 3-nitrotyrosine, a marker for peroxynitrite, increased diffusely throughout subcortical white matter with age, suggesting a potential role of nitric oxide in age-related white matter injury. In addition, we found that the density of activated microglia in the subcortical white matter of the cingulate gyrus and the corpus callosum was significantly elevated with cognitive impairment in elderly monkeys. This study suggests that microglial activation increases in white matter with age and that these increases may reflect the role of activated microglia in the general pathogenesis of normal brain aging.  相似文献   
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85.
Aerococci can be misidentified as streptococci, enterococci, pediococci, lactococci, or leuconostocs. To distinguish the genus and determine if another species is needed in the present taxon, we analyzed 37 aerococci for cellular fatty acids and compared them with 377 strains of gram-positive cocci, including the species type strains from each of the related genera. The cellular fatty acid profile of aerococci was distinguishable from other genera. Two relatively novel fatty acids found in the aerococci were identified as C16:1 omega 9c and C16:1 omega 9t. Eleven strains of aerococci (including a strain originally identified as "Gaffkya" species) were chosen for DNA-DNA reassociation studies with the type strain Aerococcus viridans ATCC 11563; DNAs from eight of these strains were more than 75% related to the type strain and had 1 to 4% divergence in related sequences. The remaining three strains were 60 to 70% related to the type strain, had 7 to 11.5% divergence, and may represent a second species, Aerococcus genospecies 2. beta-Glucuronidase, alpha-galactosidase, and beta-galactosidase were useful in characterizing the aerococci.  相似文献   
86.
The effects of anabolic steroid use on male sexual behavior were assessed using a structured clinical interview administered to male body builders currently using steroids, and to two comparison groups (body builders with a past but not current history of steroid use, and a group of natural body builders who had never used steroids). Current anabolic steroid users had a significantly higher coital and orgasmic frequency than did comparison athletes. They also reported a significantly higher incidence of erectile difficulties during the past month. Beliefs concerning the sexually stimulating effects of steroids did not correlate with the frequencies of specific sexual behaviors. The data support the contention that anabolic steroids, as androgenic compounds, enhance sexual desire.  相似文献   
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88.
The purpose of this study was to examine the salaries for entry-level positions in athletic training during the year 1992. An entry-level position was defined as an athletic trainer, certified by the National Athletic Trainers' Association (NATA), with no full-time paid employment experience. According to the “Placement Vacancy Notice” published by the NATA, there were 234 entry-level vacancies in the hospital/clinic, 135 with the college/university, and 58 at the high school setting. A survey was designed and mailed to the location of each of these 427 entry-level positions. Distribution of responses was 78 (33%), 55 (41%), and 23 (40%) for hospital/clinic, college/university, and high school, respectively. Overall, beginning salaries for entry-level athletic training positions were $23,108 (± $3,309) for a bachelor's degree and $25,223 (± $3, 794) for a master's degree. A stipend ($4,219 ± $1,458) was included in most of the high school positions. Term of contract for high school was usually 10 months (10.2 ± 0.8 months), hospital/clinic was 12 months (11.9 ± 0.6 months), while the college/university varied from 9 to 12 months (10.8 ± 1.3 months). Further studies are recommended to establish salary norms and trends for entry-level positions so that athletic trainers will understand what monetary compensation is expected for their services.  相似文献   
89.
We assessed reproducible definition of two standardized co-ordinate systems for intersubject analysis of brain images. The baselines in the two co-ordinate systems were a modification of the canthomeatal (inCM) line and the anterior-posterior commissural )AC-PC) line. Axial spin-echo MR images of four subjects at 1.5T were used. Operator error was computed from the replicate analyses of two operators. The mCM line was determined by the lens of the eye and the internal auditory canal, and the AC-PC line was determined by the intersection of the AC and PC with the interhemispheric fissure. Reproducibility of the mCM markers (SD=0.59 mm) did not differ significantly from that of the AC-PC line (SD=0.68 mm). The measurement error of the angle of the baseline (), however, was more than 7 times as large for the AC-PC line as for the mCM line. An additional error affecting the rostrocaudal rotation of the co-ordinate systems, attributable to the distance between the anatomic markers, was 2.1 and 3.6° (3 mm and 5 mm slice thickness) for the mCM co-ordinate system and 8.2 and 11.0° (3 mm and 5 mm slice thickness) for the AC-PC system. The AC-PC line based co-ordinate system is therefore, less reproducible than the mCM line based system. this could be improved if a combination of axial and sagittal images were used for the definition of the AC-PC line.  相似文献   
90.
Self-rated health and mortality in people with diabetes.   总被引:1,自引:0,他引:1       下载免费PDF全文
OBJECTIVES. This study examined whether self-rated health is an independent and significant predictor of mortality in people with diabetes, using data collected in the Wisconsin Epidemiologic Study of Diabetic Retinopathy. METHODS. Participants were asked to rate their health in comparison with others their age. A proportional hazards model was used to regress survival time on self-rated health and a number of covariates measuring physical health. RESULTS. People with younger onset diabetes (n = 891) who rated their health relative to their peers as "worse" or "don't know" were no more likely to die than those rating their health as "the same" or "better" when physical health status was controlled. In contrast, those with older onset diabetes (n = 987) who rated their health as "worse" or "don't know" were almost twice as likely to die as those rating their health as "the same" or "better" when physical health status was controlled. CONCLUSIONS. Self-rated health is a significant predictor of mortality in people with older onset diabetes but not in those with younger onset diabetes when physical health status is controlled.  相似文献   
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