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A case of acute cervical epidural abscess is presented. The use of intraoperative spinal sonography is discussed as a valuable adjunct in the evaluation and treatment of these uncommon lesions. 相似文献
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V H Denenberg R H Fitch L M Schrott P E Cowell N S Waters 《Behavioral neuroscience》1991,105(4):562-566
Previous research found that the corpus callosum of male rats is larger than that of females; handling rats in infancy enhances this sex difference; and female rat pups, when handled in infancy and given 1 injection of testosterone propionate (TP) on Day 4 of life, will have callosa as large as those of males. In 2 experiments, male pups were castrated on Day 1 or received sham surgery; female pups were injected with TP on Day 4 or received an oil injection. Litters were handled or nonhandled. The previous finding that females, when handled and given TP in infancy, have a larger callosum was confirmed; however, a TP effect when administered to nonhandled females was not found. Because handling is known to cause a corticosterone release, these findings were interpreted as evidence of a developmental interaction between adrenal and gonadal hormones at the cortical level. 相似文献
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Karyotypes of 36 lymphoblastoid cell lines established by Epstein-Barr virus (EBV) transformation of peripheral blood lymphocytes (PBL) of eight normal individuals and 28 patients with various nonhematologic malignancies were analyzed. In seven lines (19.4%), cells with trisomy 12 were noted, with clonality in two of these lines. In two of 11 metaphases with such trisomy, chromosome 12 was involved in structural rearrangements [t(8;12)(q12;p12) and t(12;12)(q11;q24)]. No cells with trisomy 12 were observed in phytohemagglutinin (PHA)-stimulated PBL cultures of these individuals. In 250 individuals (normal and with nonhematologic malignancies) examined in our laboratory in the last 5 years, extra copies of chromosome 12 in PHA-stimulated PBL cultures were observed in only five of 23,216 cells (0.02%). There were no cases of clonality in these samples. The frequency of an extra chromosome 12 was comparable to that of the other chromosomes except 21 and X, whose frequency of occurrence was 0.08% and 0.09%, respectively. These findings should be considered random events in PHA-stimulated PBL. On the contrary, in lymphoblastoid cell lines established by EBV transformation, trisomy of chromosome 12 was the most frequent numerical abnormality. It was observed in 64.7% of all cases with chromosome gains and therefore could not be considered a random occurrence. The specificity of this phenomenon for EBV transformation is supported by the results of cytogenetic analysis of eight lymphoblastoid cell lines established by an alternative procedure in our laboratory [1]. In 400 cells analyzed not a single cell with trisomy 12 was observed. We suggest that EBV transformation might either randomly induce formation of such cells in immortalized B-cell populations or show potentially blastomogenic cells or proneness to their formation in certain individuals who could be predisposed to develop lymphoproliferative diseases, especially chronic lymphocytic leukemia (CLL) in which trisomy of chromosome 12 is the most common alteration. 相似文献
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Barry J. Cusack Stephan P. Young Vicki L. Loseke Michelle R. Hurty Loring Beals Richard D. Olson 《Cancer chemotherapy and pharmacology》1992,30(2):145-148
Summary Malnutrition involving protein deficiency, which commonly occurs in cancer patients receiving anthracycline treatment, is considered to be a risk factor for the development of cardiotoxicity. Protein deficiency has been shown to impair the metabolism of drugs such as theophylline and acetaminophen. If protein deficiency also impairs anthracycline metabolism, it could explain at least in part the enchanced anthracycline toxicity associated with malnutrition. We tested this idea by determining the effect of a low- protein, isocaloric diet on doxorubicin pharmacokinetics in rabbits. The animals were randomized into two groups for 8–12 weeks. Rabbits in group 1 received a low-protein (5%), isocaloric diet, whereas those in group 2 received a normal-protein (15%) diet. Both groups (group 1,n=15; group 2,n=14) were given 5 mg/kg doxorubicin by i.v. bolus. After doxorubicin injection, blood samples were obtained over the next 52 h for the measurement of doxorubicin and doxorubicinol plasma concentrations by high-performance liquid chromatography (HPLC) with fluorometric detection. The low-protein diet significantly decreased doxorubicin clearance (48±3 vs 59±4 ml min–1 kg–1;P<0.05), prolonged the terminal climination half-life (28±2 vs 22±2 h;P<0.05), and increased the area under the plasma concentration/time curve extrapolated to infinity (1722±122 vs 1405±71 ng h ml–1;P<0.05) as compared with the values determined for rabbits fed the standard rabbit chow (15% protein). The volume of distribution for doxorubicin was not altered by the low-protein diet. In addition, in rabbits fed the the low-portein diet, the terminal elimination half-life of the alcohol metabolite, doxorubicinol was prolonged (52±5 vs 40±2 h;P<0.05). Thus, a low-protein diet causes a reduction in the ability of rabbits to eliminate doxorubicin and possibly its alcohol metabolite doxorubicinol. If a similar alteration in anthracycline pharmacokinetics occurs in malnourished cancer patients, this phenomenon may contribute to their increased risk of developing cardiotoxicity associated with anthracycline therapy.Supported by the Department of Veterans Affairs and the American Heart Foundation 相似文献
19.
Respiratory symptoms among elderly people in the New Forest area as assessed by postal questionnaire. 总被引:3,自引:0,他引:3
This study was carried out to estimate the prevalence of respiratory symptoms among people aged 65 years and older and assess the value of a postal survey in obtaining this information. A questionnaire was sent to 2011 subjects (957 men) drawn by age-stratified random sampling from the age-sex registers of four New Forest group practices (1:3.3 sample). A total of 1803 replied, a 96.2% response after excluding 136 who had died or moved from the area. The accuracy of replies was verified for 355 (20%) randomly selected subjects. Forty per cent had no respiratory symptoms. Exertional breathlessness was common (38%), increasing in prevalence with age but not with smoking history, and was the only symptom reported by 10% of subjects. Only 14.2% were current smokers; more of the subjects aged 85 years and over were lifelong non-smokers. Two hundred and ninety-six (16.4%) had chronic bronchitis, which was more common among smokers; 151 (8.4%) gave a history of asthma, of whom half (76) had active asthma, which was slightly less common among the very elderly subjects. Only 489 (27.1%) of subjects had seen their doctors with chest symptoms during the preceding 2 years. 相似文献
20.
We report on four children who received cis-platinum simultaneously with, or in one case 10 months after, cranial irradiation and experienced exaggerated ototoxicity affecting all audible frequencies. The hearing loss was severe, affecting the critical areas for speech perception, and necessitated the provision of bilateral hearing aids. The audiograms of these patients are shown and compared to those of four children who had received cis-platinum as part of their treatment for neuroblastoma but without cranial irradiation. The precipitation of the exaggerated hearing loss with the administration of cis-platinum in one patient 10 months after finishing cranial irradiation suggests that care should be taken in the timing of cis-platinum administration in relation to concurrent or previous cranial irradiation. 相似文献