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71.
Constraints on biological effects of weak extremely-low-frequency electromagnetic fields 总被引:3,自引:0,他引:3
RK Adair 《Canadian Metallurgical Quarterly》1991,43(2):1039-1048
72.
RK Sommers 《Canadian Metallurgical Quarterly》1998,87(1):187-198
It has long been recognized that a basic dimension to the lexical organization of the brain is semantic, and some brain mapping studies have indicated that the brain fields are distinctly different from some grammatical classes. Findings from the present investigation showed consistent relationships between 29 aphasic adults' performances on tasks involving graphic and gestural skills and those involving sequential recall of spoken words from different word categories. Each adult received the Porch Index of Communication Abilities which relies upon the physical manipulation of objects to assess verbal, gestural, and graphic abilities. Scores on a test requiring recall of word strings of nouns, verbs, adverbs, adjectives, or prepositions were used to predict the subscale scores from the Graphic and Gestural factors of the index. Recall scores for verb and preposition were predictive of the aphasic subjects' performances on the Graphic subscale, and noun and preposition scores were predictors of subjects' scores on the Gestural subscale. The results are related to other research showing that verb and preposition skills are predictive of fine motor abilities of children with communication disorders and brain-mapping studies. Some discussion centers on possible overlapping functions of brain activity involving word categories, language, and fine motor skills. 相似文献
73.
Ionizing radiation is believed to stimulate the repopulation of squamous carcinoma cells that survive the early portion of a fractionated course of radiotherapy. To characterize any intrinsic radiation-induced adaptive response and to examine whether epidermal growth factor (EGF) influences this response, A431 and 183A cells were irradiated with repeated daily exposures of 0.5-0.75 Gy and then grown in monolayer culture for 7 days with or without EGF at a 1 ng/ml concentration. Cell numbers were quantified using a microtiter dye-reduction assay. EGF alone caused approximately 70% and 30% growth inhibition of human SC A431 and 183A cells, respectively. Although radiation alone did not affect proliferative rates in these conditions, radiation eliminated the EGF-related growth inhibition in both cell lines. This effect was dose dependent in single radiation exposure experiments. Cell cycle analyses indicated that EGF initially promoted entry into S-phase 3 days after treatment but caused a G1-S block after 7 days. Treatment with radiation recruited cells into S-phase and G2-M, an effect which was sustained 7 days after treatment, overriding the influence of EGF. Radiation-induced modulation of the response of human squamous carcinoma cells to EGF in vitro after single and repeated radiation exposures suggests a proliferation response that may underlie enhanced repopulation of tumor clonogens in vivo. 相似文献
74.
75.
The combination of ifosfamide, carboplatin and etoposide (modified ICE), was evaluated for its toxicity and activity in relapsed or refractory aggressive non-Hodgkin's lymphoma. Twenty patients, 14-69 years of age, with relapsed (19 cases) or refractory (one case) aggressive non-Hodgkin's lymphoma were treated with modified ICE therapy, consisting of ifosfamide 6 g/m2 (1.2 g/m2 day 1-5), carboplatin 400 mg/m2 (day 1) and etoposide 500 mg/m2 (100 mg/m2 day 1-5). The regimen was repeated at approximately 28-day intervals. All patients had undergone a doxorubicin-containing regimen before modified ICE therapy. Median total dose of previously received doxorubicin was 406 mg/m2 (range: 200-825 mg/m2). The median interval from diagnosis to modified ICE therapy was 9.4 months (range: 3.6-121 months). Two patients achieved CR and five achieved PR out of 16 patients with measurable lesions (response rate 43.8%; 95% confidence interval 19.0-68.6%). Median overall survival was 227 days (range: 41-552 days) from the start of modified ICE therapy. Myelosuppression was the most serious toxicity, namely 16 patients (80%) and 11 patients (55%) showed grade 4 neutropenia and grade 4 thrombocytopenia after the first course, respectively. Modified ICE therapy might be an active regimen with acceptable toxicity as a salvage chemotherapy in aggressive non-Hodgkin's lymphoma. 相似文献
76.
MR Kosorok M Jalaluddin PM Farrell G Shen CE Colby A Laxova MJ Rock M Splaingard 《Canadian Metallurgical Quarterly》1998,26(2):81-88
Racial differences in insulin secretion and insulin sensitivity in healthy children were studied by administering a 2-hour hyperglycemic clamp (225 mg/dL) to 14 black and 16 white healthy adolescents (Tanner II-V), and 12 black and 11 white prepubertal children, matched for age, body mass index, and Tanner I pubertal development. In prepubertal children, fasting and first-phase insulin concentrations were higher in blacks compared with whites (14.7+/-1.3 vs 10.4+/-1.2, P=0.02, and 76.9+/-6.8 vs 52.1+/-6.4 microu/mL, P=0.016). There were no differences in second-phase insulin levels and insulin sensitivity index. In pubertal adolescents, first-phase and second-phase insulin concentrations were higher in blacks compared with whites (first-phase: 157.3+/-18.3 vs 77.0+/-8.7 microu/mL, P=0.0003; second-phase: 175.0+/-24.3 vs 108.7+/-8.8 microu/mL, P=0.012). Insulin sensitivity index was 35% lower in black adolescents compared with whites (P=0.02). These findings indicate that significant differences in insulin secretion and sensitivity are detectable early in childhood in healthy African-American vs American whites. However, genetic (race) vs environmental factors (physical activity/fitness, energy balance) should be carefully scrutinized as potential factors responsible for such differences. 相似文献
77.
WR Kirkpatrick RK McAtee SG Revankar AW Fothergill DI McCarthy MG Rinaldi TF Patterson 《Canadian Metallurgical Quarterly》1998,36(5):1330-1332
A simple screening method for fluconazole susceptibility of Cryptococcus neoformans using 2% dextrose Sabouraud dextrose agar (SabDex) with fluconazole was compared to the National Committee for Clinical Laboratory Standards (NCCLS) broth macrodilution method. By this method, fluconazole-susceptible C. neoformans isolates are significantly smaller on medium with fluconazole than on fluconazole-free medium. Isolates with decreased susceptibility have normal-size colonies on medium containing fluconazole. The 48-h NCCLS broth macrodilution MICs (NCCLS MICs) for isolates with normal-size colonies on 8- or 16-microg/ml fluconazole plates were predicted to be > or =8 or > or =16 microg/ml, respectively. On medium with 16 microg of fluconazole per ml, all strains (84 of 84) for which the NCCLS MICs were <16 microg/ml were correctly predicted, as were all isolates (7 of 7) for which the MICs were > or =16 microg/ml. Agar dilution appears to be an effective screening method for fluconazole resistance in C. neoformans. 相似文献
78.
Thirty-four adults were vaccinated with 1/50 of the usual dose of meningococcal polysaccharide vaccine (1 microg of A, C, Y, and W135 polysaccharides, given intramuscularly). This dose was selected as a probe to assess B cell memory. The probe elicited meningococcal C bactericidal antibody responses in all 18 adults who had been vaccinated 4 years earlier with an investigational meningococcal A and C oligosaccharide-protein conjugate vaccine and in the majority of the 11 subjects vaccinated for the first time. In contrast, the responses of the 5 adults given a full dose of licensed polysaccharide vaccine 4 years earlier were <1/10 of those of the other 2 groups. Thus, adults previously given a full dose of meningococcal polysaccharide vaccine show evidence of immunologic refractoriness to group C polysaccharide, whereas refractoriness is not observed after conjugate vaccination. These findings have implications for the use of meningococcal polysaccharide vaccine when the risk of disease is low. 相似文献
79.
Previous research has highlighted the high prevalence (30-60%) of comorbid anxiety and mood disorders in clients with substance misuse disorders and, equivalently, a third of those with affective disorder report a history of substance use disorder (Kessler et al., 1994; Regier et al., 1990; Robins & Regier, 1991). This article reviews the management of such cases and identifies key issues in the assessment process, as well as potential avenues for treatment. Other articles have highlighted the increased service utilisation and the cost of care and treatment of comorbidity. This article will primarily focus on the management of individual cases and will briefly refer to issues of service organisation. Although antidepressant or anxiolytic pharmacotherapy may have a role in the treatment of severe disorders, the benefits of using these medications must be balanced against the increased risk of side-effects or adverse reactions in individuals who continue to engage in substance misuse or who have medical complications associated with drug or alcohol dependency. Effective psychosocial approaches largely focus on brief, empirically tested manualised therapies such as cognitive therapy (Carroll, 1998a). However, modifications are required to such approaches to ensure that the interventions are tailored to the needs of clients exhibiting comorbidity. The data available demonstrate some evidence for the benefits of structured psychological approaches, but more sophisticated randomized controlled trials are required to evaluate the efficacy of both psychological and pharmacological approaches. 相似文献
80.