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21.
22.
We report a rare example of bilateral primary malignant phyllodes tumours. The diagnosis was supported by the identification of a benign epithelial element in each lesion. The case illustrates the typical dimorphic features of malignant phyllodes tumours. A contralateral tumour should not be regarded as metastatic without histological confirmation. 相似文献
23.
Alfred E Buxton Hugh Calkins David J Callans John P DiMarco John D Fisher H Leon Greene David E Haines David L Hayes Paul A Heidenreich John M Miller Athena Poppas Eric N Prystowsky Mark H Schoenfeld Peter J Zimetbaum Paul A Heidenreich David C Goff Frederick L Grover David J Malenka Eric D Peterson Martha J Radford Rita F Redberg 《Journal of the American College of Cardiology》2006,48(11):2360-2396
24.
Daniel B. Costa Christopher A. Fisher Kenneth B. Miller German A. Pihan David P. Steensma Richard J. Gibbons Douglas R. Higgs 《European journal of haematology》2006,76(5):432-435
Abstract: We describe a patient with acquired alpha-thalassemia myelodysplastic syndrome (ATMDS). A previously healthy 66-year-old man presented with hemoglobin of 9.3 g/dL, mean corpuscular volume 59 fL, and a bone marrow aspirate with increased erythroid precursors and hypolobulated megakaryocytes. Hemoglobin H inclusions were seen in most red cells after 1% brilliant cresyl blue supravital stain of the peripheral blood. At the molecular level, we identified of a novel mutation in the most 3' exon of the ATRX gene ( C GA→ T GA substitution in codon 2407) resulting in a premature termination codon (p.R2407X). This case provides further evidence for a link between ATRX mutations and ATMDS, and suggests a possible role for the conserved Q-box element in ATRX function. 相似文献
25.
M. S. Levine A. M. Adinolfi R. S. Fisher C. D. Hull D. Guthrie N. A. Buchwald 《Brain research》1988,440(2):267-279
These studies provide information on the changes in the ultrastructure in the caudate nucleus of aged cats. The major findings was that there was a decrease in the density of synapses in caudate neuropil. This decrease occurred in animals after 3 years of age and remained relatively constant in older animals. In conjunction with this change a population of unusually long synapses also occurred. These larger synaptic appositions were associated with enlarged spine heads. The caudate also showed a number of qualitative ultrastructural alterations. Many neurons contained accumulations of lipofuscin or lipopigment granules in aged animals. These inclusions occurred in both soma and dendrites of neurons and all types of glial cells. A unique configuration of collapsed agranular cisterns also was observed in aged animals. The present results indicate that decreases in synaptic density may by one morphological event underlying functional alterations observed in caudate neurons in aged cats. 相似文献
26.
Background: The gastric bypass operation has evolved since 1966 when it was first introduced. The purpose of this study was
to determine the present state of gastric bypass by consensus among the members of the American Society for Bariatric Surgery
(ASBS). Method: A questionnaire was sent to all members of the ASBS. Forty-three percent responded reporting over 41,200 cases.
Results: Results were analyzed by using χ2 tests with a null hypothesis. Surgeons agreed on several technical aspects, preferring a vertical to a horizontal stapleline;
estimating, rather than measuring, the pouch volume at an average of 22 cc. Few surgeons divide the short gastric vessels,
and only 25% of surgeons polled use a restrictive ring or band proximal to the gastroenterostomy. Most surgeons calibrate
the gastroenterostomy, reporting a preferred average diameter of 12.3 cm. There was no consensus regarding forming the gastroenterostomy,
58% preferring hand-sewn and 42% stapled anastomoses. There was no consensus regarding dividing the gastric pouch from the
bypassed stomach: Conclusion: The preferred gastric bypass is vertical, with the pouch estimated at 20-25 cc, and the gastroenterostomy
calibrated at 12 mm diameter. The short gastric vessels need not be divided, and restrictive bands or rings are not preferred.
This technique of gastric bypass should be used as the control procedure when modifications are tested in future trials. Randomized
prospective studies are suggested to probe the benefits of division of the stomach pouch from the bypassed stomach. 相似文献
27.
28.
Kay Fisher Neville A McBrien Kenneth J Ciuffreda 《Clinical & experimental optometry》1997,80(4):139-144
The influence of continuous variation in dioptric demand on the accommodative hysteresis induced at near distances was examined in 14 visually-normal young adults. Tonic accommodation was measured before and after 10 minutes of sustained focus using a constant stimulus at 5 D, 6.5 D, and 8 D, as well as a stimulus which slowly and alternately increased and decreased over the continuous range from 5 D to 8 D. For approximately half the subjects, dioptric demand had to be very high (8 D) under static conditions to produce moderate but significant hysteresis, yet little or no attenuation of the effect occurred under the dynamic condition. For other subjects who consistently showed very large tonic changes (1.4 D or more) under static conditions, the hysteresis effect generated under dynamic conditions was greatly reduced (approximately 50 per cent) in magnitude. These findings suggest that the degree to which continuous variation in dioptric demand will disrupt the adaptive process may depend on individual differences in the rate and/or maximum level of tonic accommodative change. Such a relationship could have bearing on the particular strategy recommended for individuals who tend to experience blur at distance following nearwork. 相似文献
29.
S W Fisher 《Ecotoxicology and environmental safety》1992,23(1):11-21
Chlordimeform (CDF) was tested for its ability to act jointly with an organophosphorus insecticide (parathion) and a series of carbamate insecticides. Three arthropod species were used as test subjects: the two-spotted spider mite, Tetranychus urticae; the German cockroach, Blatella germanica; and the flour beetle, Tenebrio castaneum. However, CDF antagonized the toxicity of parathion toward B. germanica while it acted in a greater than additive fashion toward T. castaneum. No combination of CDF and insecticide tested acted jointly toward T. urticae. Species-specific differences in sensitivity, absorption, metabolism, and mode of delivery account for the varying results. Metabolic studies of pairs of compounds using two radiolabeled carbamates showed that CDF altered the metabolic detoxification of both carbaryl and aldicarb. The results suggest that CDF may inhibit MFOs as its mode of action. 相似文献
30.
A comparative analysis of radiological and surgical placement of central venous catheters 总被引:3,自引:1,他引:2
Kieran D. McBride Ross Fisher Neil Warnock David A. Winfield Malcolm W. Reed Peter A. Gaines 《Cardiovascular and interventional radiology》1997,20(1):17-22
Purpose To compare the differences in practice and outcome of all radiologically and surgically placed central venous catheters retrospectively
over a 2-year period simultaneously, at a single institution.
Methods A total of 253 Hickman catheters were inserted in 209 patients; 120 were placed radiologically in 102 patients and 133 were
placed surgically in 107 patients. The indication was chemotherapy in 76% of radiological and in 47% of surgical cases; the
remainder were for total parenteral nutrition and venous access.
Results There were 6 (4.5%) primary surgical failures and a further 17 (13%) surgical cases requiring multiple placement attempts.
Pneumothorax occurred once (0.8%) surgically and four times (3.3%) radiologically. There were no radiological primary misplacements
but there were five (3.7%) surgical ones. Catheter or central vein thrombosis occurred in four (3.3%) radiological and five
(3.7%) surgical cases. The rate of infection per 1000 catheter-days was 1.9 in radiologically placed catheters and 4.0 in
surgically placed ones (p<0.001). Average catheter life-span was similar for the two placement methods (100±23 days).
Conclusion Radiological placement is consistently more reliable than surgical placement. There are fewer placement complications and
fewer catheter infections overall. 相似文献