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21.
DH Mallon M Kostalas FJ MacPherson A Parmar A Drysdale E Chisholm 《Annals of the Royal College of Surgeons of England》2013,95(4):258-262
Introduction
Fine needle aspiration (FNA) is a safe and quick method of diagnosing superficial lumps, which aids preoperative planning. However, FNA of the parotid gland has not gained the widespread acceptance noted in other head and neck lumps. The aim of this study was to determine the ability of FNA of the parotid gland to differentiate benign and malignant disease, and to determine the impact on surgical outcome.Methods
A retrospective analysis of 201 consecutive parotid operations with preoperative FNA in a large district hospital in the UK was performed. The diagnostic characteristics were calculated for benign and malignant disease, and the impact on surgical procedure was determined.Results
In identifying benign disease, FNA has a sensitivity of 85% and a specificity of 76%. In detecting malignant disease, FNA has a sensitivity and specificity of 52% and 92% respectively. A false positive on FNA was associated with a higher incidence of neck dissection.Conclusions
FNA is a useful diagnostic test. However, owing to low sensitivity, it is necessary to interpret it in the context of all other clinical information. 相似文献22.
Dihydropteridine reductase activity in dried blood spots: effects of aging and senile dementia of the Alzheimer type. 下载免费PDF全文
Dihydropteridine reductase (EC 1.6.99.7) (DHPR) activity was measured in blood spots from 50 neonates, 52 healthy adults aged 30-62 years, and 21 elderly controls aged 67-97 years, as well as 32 demented patients of whom 25 had senile dementia of the Alzheimer type. Enzyme activity was stable for seven days at 4 degrees C and for at least 14 days at -20 degrees C. No important difference was found between the DHPR activity of venous and capillary blood. DHPR activity was considerably lower in the healthy adult group compared with neonates and the elderly group, and there was no sex difference at any age. The erythrocyte DHPR activity of patients with senile dementia of the Alzheimer type was similar to that of elderly controls. This result differs from that previously reported for leucocytes. 相似文献
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Fetal erythropoiesis in steel mutant mice. III. Defect in differentiation from BFU-E to CFU-E during early development 总被引:5,自引:1,他引:5
Erythroid progenitor cells in +/+ and Sl/Sld fetal livers manifested as burst-forming units-erythroid (BFU-E) and colony-forming units- erythroid (CFU-E) were assayed in vitro during early development. The proportion of BFU-E was higher as mutant than in normal fetal livers. On the other hand, the proportion of CFU-E was less in the mutant than in the normal. These results suggest that the defect in Sl/Sld fetal hepatic erythropoiesis is expressed at the steps of differentiation that effect the transition from BFU-E to CFU-E. 相似文献
24.
Virtual endocast of Ignacius graybullianus (Paromomyidae,Primates) and brain evolution in early primates 下载免费PDF全文
Mary T. Silcox Claire K. Dalmyn Jonathan I. Bloch 《Proceedings of the National Academy of Sciences of the United States of America》2009,106(27):10987-10992
Extant primates are distinctive among mammals in having relatively large brains. As stem primates, Paleogene plesiadapiforms provide direct information relevant to the earliest stages in the evolution of this characteristic. Here we describe a virtual endocast reconstructed from ultra high resolution X-ray computed tomography data for the paromomyid plesiadapiform Ignacius graybullianus (USNM 421608) from the early Eocene of Wyoming. This represents the most complete endocast known for a stem primate, allowing for an unprecedented study of both size and fine details of anatomy. Relative to fossil and extant euprimates, I. graybullianus had large olfactory lobes, but less caudal development of the cerebrum and a poorly demarcated temporal lobe, suggesting more emphasis on olfaction and a less well developed visual system. Although its brain was small compared to those of extant primates, the encephalization quotient of I. graybullianus is higher than that calculated for Paleocene Plesiadapis cookei and overlaps the lower portion of the range documented for fossil euprimates. Comparison to the basal gliroid Rhombomylus suggests that early primates exhibited some expansion of the cerebrum compared to their ancestors. The relatively small brain size of I. graybullianus, an arboreal frugivore, implies that neither arboreality nor frugivory was primarily responsible for the expanded brains of modern primates. However, the contrasts in features related to the visual system between I. graybullianus and fossil and extant euprimates suggest that improvements to these portions of the brain contributed to increases in brain size within Euprimates. 相似文献
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BM Winklhofer-Roob MA van't Hof DH Shmerling 《Acta paediatrica (Oslo, Norway : 1992)》1995,84(10):1132-1136
The aim of this study was to determine the efficacy of long-term oral β -carotene supplementation for correcting impaired β -carotene status in cystic fibrosis patients. Thirty-five patients (2.3-30.5 years of age) with coefficients of fat absorption of 46-96% (median 88%) received β -carotene 0.5 mg/kg daily and were followed over a 16-month treatment period. Baseline plasma β -carotene concentrations in patients (meanSD, 0.090.06 μ mol/1) were significantly lower than those of age-matched controls (0.860.56 μ mol/1) ( p < 0.0001). Concentrations increased rapidly and reached a plateau at or before 3 weeks that was maintained throughout the study period. Values obtained at 3 weeks (0.890.64 μ mol/1) were significantly higher ( p < 0.0001) than those at baseline and did not differ from controls. Plasma retinol and α -tocopherol concentrations increased during the observation period, but remained within normal ranges. Plasma retinyl palmitate, which was below the detection limit in all but one patient at baseline, did not increase. Thus oral β -carotene supplementation is effective and normalizes β -carotene status of cystic fibrosis patients without evidence of significant side effects. β -Carotene, cystic fibrosis, LDL-cholesterol, oral supplementation, retinol, α-tocopherol 相似文献
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Aspergillus endocarditis in chronic granulomatous disease 总被引:2,自引:0,他引:2
We report the first case, to our knowledge, of Aspergillus endocarditis in chronic granulomatous disease in a patient who also had an atrial septal defect. A diagnosis was made on culture of the organism from the mass despite extensive prior investigation. The presence of distinctive skin lesions as a diagnostic clue of fungaemia is highlighted. Possible advances in diagnosis by detection of fungal cell wall components and in prophylaxis by use of itraconazole are referred to. We conclude that fungal endocarditis should be considered in this condition, especially in the presence of a structural heart defect. 相似文献
30.