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171.
This study was undertaken to clarify several aspects of morphological and taxonomic characters of Physaloptera bispiculata Vaz and Pereira, 1935, a parasite of the water rat, Nectomys squamipes. The cephalic structures (including lips, papillae, teeth, amphids, and porous areas) and details of the posterior end of male and female adult worms were examined by scanning electron microscopy, leading to the addition of new taxonomic characters for this species. We consider P. bispiculata a valid species, based on a comparative analysis of the specific characters for P. bispiculata and P. getula Seurat, 1917, including the morphology and morphometry of body structures as well as number and disposition of caudal papillae of the males. 相似文献
172.
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
173.
Wu Newman Zhao Swain Ding & Phillips 《Fatigue & Fracture of Engineering Materials & Structures》1998,21(11):1289-1306
The small crack effect was investigated in two high-strength aluminium alloys: 7075-T6 bare and LC9cs clad alloy. Both experimental and analytical investigations were conducted to study crack initiation and growth of small cracks. In the experimental program, fatigue tests, small crack and large crack tests were conducted under constant amplitude and Mini-TWIST spectrum loading conditions. A pronounced small crack effect was observed in both materials, especially for the negative stress ratios. For all loading conditions, most of the fatigue life of the SENT specimens was shown to be crack propagation from initial material defects or from the cladding layer. In the analysis program, three-dimensional finite element and weight function methods were used to determine stress intensity factors and to develop SIF equations for surface and corner cracks at the notch in the SENT specimens. A plasticity-induced crack-closure model was used to correlate small and large crack data, and to make fatigue life predictions. Predicted crack-growth rates and fatigue lives agreed well with experiments. A total fatigue life prediction method for the aluminium alloys was developed and demonstrated using the crack-closure model. 相似文献
174.
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
175.
Activity from ventral subicular and hippocampal CA1 neurons was recorded in rats exploring a 4-arm radial maze in which the local and distal cues could be manipulated. Cells from both regions exhibited place fields, although ventral subicular neurons had larger fields than hippocampal cells. Rotation of the local and distal cues in opposite directions produced movement of the place fields in either direction or a complete change in firing pattern. Simplifying the environment also produced changes in place field location. Despite similarities between regions, subiculum fields decreased in size whereas hippocampal fields increased in the simple environment. These findings suggest that subicular cells may receive converging input from several hippocampal neurons and code more complex configurations of the cues. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
176.
177.
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
178.
The aim of this study was to examine the in vitro activity of fusidic acid against bacterial isolates from conjunctival swabs. Conjunctival swabs from 213 patients with conjunctivitis were examined. One or more pathogens were grown from 73 patients. Forty per cent of isolates were resistant to fusidic acid on disc sensitivity testing. Reduced sensitivity was detected by minimum inhibitory concentration testing in many isolates of H. influenzae and an isolate of S. pneumoniae. In addition, the in vitro activity of fusidic acid was determined against upper respiratory tract isolates of H. influenzae, S. pneumoniae and M. catarrhalis; this showed that many isolates had a reduced sensitivity to fusidic acid. Topical fusidic acid may not be optimal empiric therapy of bacterial conjunctivitis. 相似文献
179.
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
180.
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