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31.
Shafqat Hasan Ali N A Jilaihawi Dhruva Prakash 《European journal of cardio-thoracic surgery》2005,28(1):7-10
OBJECTIVE: Iatrogenic Oesophageal perforations are a dreaded complication and there is no consensus as to their best management. The aim of our study was to assess the results of conservative management in these cases. METHODS: Twenty-six patients with iatrogenic perforations of the oesophagus treated over a 10-year period were reviewed retrospectively. They were managed conservatively by keeping them nil by mouth on intravenous fluids and intravenous antibiotics. Out of these 26, nine were patients of carcinoma of the oesophagus while the remaining 17 had benign pathologies. Twenty-two were diagnosed within 6h, while the remaining four were diagnosed over 24h after perforation. Twenty-three of the 26 were caused by oesophageal dilatations. RESULTS: Twenty-two (84.6%) of the 26 survived on this regimen. Out of the four that died, two had advanced carcinomas and died of chest complications, one died of a myocardial infarction and the fourth was an old debilitated man who died of renal failure. All four who died had extension of the leak into the pleural cavity. Early diagnosis and treatment is of critical importance and is only possible by maintaining a high index of suspicion. CONCLUSIONS: Conservative management when applied to cases of iatrogenic oesophageal perforations gives results comparable to or better that those reported in series where early surgical intervention was practised. Extension of the leak into the pleura carries a worse prognosis. 相似文献
32.
Edward J. Ciaccio PhD Hiroshi Ashikaga MD PhD Riyaz A. Kaba MD Daniel Cervantes MD Bruce Hopenfeld PhD Andrew L. Wit PhD Nicholas S. Peters MD PhD Elliot R. McVeigh PhD Hasan Garan MD James Coromilas MD 《Heart rhythm》2007,4(8):1034-1045
BACKGROUND: Infarct border zone (IBZ) geometry likely affects inducibility and characteristics of postinfarction reentrant ventricular tachycardia, but the connection has not been established. OBJECTIVE: The purpose of this study was to determine characteristics of postinfarction ventricular tachycardia in the IBZ. METHODS: A geometric model describing the relationship between IBZ geometry and wavefront propagation in reentrant circuits was developed. Based on the formulation, slow conduction and block were expected to coincide with areas where IBZ thickness (T) is minimal and the local spatial gradient in thickness (DeltaT) is maximal, so that the degree of wavefront curvature rho proportional, variant DeltaT/T is maximal. Regions of fastest conduction velocity were predicted to coincide with areas of minimum DeltaT. In seven arrhythmogenic postinfarction canine heart experiments, tachycardia was induced by programmed stimulation, and activation maps were constructed from multichannel recordings. IBZ thickness was measured in excised hearts from histologic analysis or magnetic resonance imaging. Reentrant circuit properties were predicted from IBZ geometry and compared with ventricular activation maps after tachycardia induction. RESULTS: Mean IBZ thickness was 231 +/- 140 microm at the reentry isthmus and 1440 +/- 770 microm in the outer pathway (P <0.001). Mean curvature rho was 1.63 +/- 0.45 mm(-1) at functional block line locations, 0.71 +/- 0.18 mm(-1) at isthmus entrance-exit points, and 0.33 +/- 0.13 mm(-1) in the outer reentrant circuit pathway. The mean conduction velocity about the circuit during reentrant tachycardia was 0.32 +/- 0.04 mm/ms at entrance-exit points, 0.42 +/- 0.13 mm/ms for the entire outer pathway, and 0.64 +/- 0.16 mm/ms at outer pathway regions with minimum DeltaT. Model sensitivity and specificity to detect isthmus location was 75.0% and 97.2%. CONCLUSIONS: Reentrant circuit features as determined by activation mapping can be predicted on the basis of IBZ geometrical relationships. 相似文献
33.
Finite element analysis of the effects of thermal obturation in maxillary canine teeth. 总被引:1,自引:0,他引:1
Ozgür Er Sis Darendeliler Yaman Muvaffak Hasan 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,104(2):277-286
OBJECTIVE: The purpose of the present study was to determine the distribution and level of temperature, in a model of a maxillary canine, the surrounding periodontal tissues, and the bones, during a System B heat obturation technique simulation. STUDY DESIGN: The temperature distribution was determined by using a three-dimensional finite element analysis. The tooth was assumed to have undergone an endodontic treatment before the application. Heat applications of 200 degrees C and 100 degrees C were considered. RESULTS: By using the virtual model and the simulation technique, the maximum temperature in the periodontal ligament was found to be 43.5 degrees C. CONCLUSIONS: Within the assumptions and the limitations of the study, it was determined that the simulation of System B technique created no potentially harmful levels of temperature throughout the maxillary canine model. 相似文献
34.
Gozde Erkanli Feriha Ercan Serap Sirvanci Emsal Salik Hasan Raci Yananli Filiz Onat Tangul San 《International journal of developmental neuroscience》2007,25(6):399-407
Five-day-old Wistar albino rats were injected with kainic acid (KA) or saline i.p. to investigate time-dependent alterations in morphology and number of basic fibroblast growth factor (bFGF) immunoreactive (-ir) astrocytes and neurons in hippocampus at 15, 30, and 90 days after the injections. Sections were stained with cresyl violet for morphological evaluation and bFGF immunohistochemistry was used for quantitative evaluation of bFGF-ir cell density. Fifteen days after KA injection, there was gliosis but no neuronal loss although disorganization in CA1, CA3, CA4 pyramidal layers and neuronal loss were evident 30 and 90 days after the injection. KA injected rats demonstrated significantly increased number of bFGF-ir astrocytes throughout the hippocampus and pyramidal neurons in CA2 after 15 days and decreased number of bFGF-ir cells after 30 and 90 days. The decrease in the number of bFGF-ir astroglia and neurons in long term after KA injection may indicate a decrease in the production of bFGF and/or number of bFGF-ir cells suggesting that protective effects of bFGF may be altered during epileptogenesis in hippocampus. 相似文献
35.
Depth of epidural space in children 总被引:1,自引:0,他引:1
M. A. Hasan MB ChB DA FRCA R. F. Howard BSc MB ChB FRCA A. R. Lloyd-Thomas MB BS FRCA 《Anaesthesia》1994,49(12):1085-1087
36.
37.
V S Perez M Martinez D Castano P F Brain S Hasan 《The International journal of neuroscience》1988,41(3-4):231-240
An attempt was made in two experiments to reinvestigate the effects of the antiandrogen cyproterone acetate (CA) on mouse social behavior in a variety of ethologically-assessed paired encounters. The data confirm that CA reduces offense (threat and attack) in animals when both subjects receive the material but that CA has no such action in other pairings. This suggests that CA's major suppressive effect on "hostility" is expressed in mice via a reduction in "attack-promoting" pheromone production. Indeed, there was evidence in the more chronic study that CA, could augment (via a central mechanism?) offense in subjects paired with docile anosmic opponents. Changes in defense were largely responses to variations in the degree of attack to which animals were subjected. The antihormone also had actions on other aspects of behavior including sexual activity, social investigation and immobility in such tests. CA had a potent suppressive action on the weights of sex accessory glands. The data do not suggest that CA can be used as a specific antihostility agent. 相似文献
38.
Hasan I. Atrah Ronald J. L. Davidson 《European journal of nuclear medicine and molecular imaging》1989,15(2):57-60
The results of all dual isotope tests (2142) carried out on 1989 patients, 807 males (40.6%) and 1182 females (59.4%), during a 10 year period (1976–1985 inclusive) in the Grampian Health Board Area (population 497,272) have been reviewed. Patient age ranged from 5–95 years with 45.5% over 60 years. The referring specialities were Gastroenterology (47.6%), Haematology (11.3%), Paediatries (2.1%) and all others (39.9%). According to the manufacturer's recommended criteria, results were classified as normal in 1054 (49.2%), abnormal in 659 (30.8%), equivocal in 337 (15.7%) and unsatisfactory in 92 (4.3%) tests. Vitamin B12 malabsorption of ileal type was indicated in 544 tests (25.4%) and of gastric type in 115 (5.4%). Of the latter, 76 were related to pernicious anaemia, 10 to previous gastric surgery and 2 to gastric carcinoma. Of the 337 patients with equivocal results, 138 patients were reviewed and 115 (83.3%) found to have a documented cause for gastric malabsorption (96 pernicious anaemia and 19 previous gastric surgery). In 172 patients with proven pernicious anaemia the manufacturer's recommended criteria for gastric malabsorption were completely satisfied in only 76 (44.3%) but 167 (96.5%) had an excretion ratio 1.3 and 127 (73.8%) a ratio 1.7. Unsatisfactory tests were mainly due to incomplete urine collection (91.3%) or contamination with another isotope (5.4%). 相似文献
39.
Huupponen E Himanen SL Hasan J Värri A 《Medical & biological engineering & computing》2003,41(6):727-732
A fully automatic method to analyse electro-encephalogram (EEG) sleep spindle frequency evolution during the night was developed
and tested. Twenty allnight recordings were studied from ten healthy control subjects and ten sleep apnoea patients. A total
of 22 868 spindles were detected. The overall mean spindle frequency was significantly higher in the control subjects than
in the apnoea patients (12.5Hz against 11.7Hz, respectively; p<0.004). The proposed method further identified the sleep depth
cycles, and the mean spindle frequency was automatically determined inside each sleep depth cycle. In control subjects, the
mean spindle frequency increased from 12.0Hz in the first sleep depth cycle to 12.6Hz in the fifth cycle. No such increase
was observed in the sleep apnoea patients. This difference in the spindle frequency evolution was statistically significant
(p<0.004). The advantage of the method is that no EEG amplitude thresholds are needed. 相似文献
40.
Robert A. Hirst Hasan Yesilkaya Edwin Clitheroe Andrew Rutman Nichola Dufty Timothy J. Mitchell Christopher OCallaghan Peter W. Andrew 《Infection and immunity》2002,70(2):1017-1022
The Streptococcus pneumoniae pore-forming toxin, pneumolysin, is an important virulence factor in pneumococcal pneumonia. The effect of pneumolysin on human lung epithelial and monocyte cell viability was compared. Pneumolysin caused a dose-dependent loss of viability of human lung epithelial (A549 and L132) and monocyte (U937 and THP-1) cell lines. Analysis of the dose-response curves revealed similar log 50% inhibitory concentration (pIC(50)) values for A549, L132, and THP-1 of 0.12+/- 0.1, 0.02+/- 0.04, and 0.12+/- 0.13 hemolytic units (HU), respectively, but U937 cells showed a significantly greater pIC(50) of 0.42+/- 0.12 HU. Differentiation of A549 and L132 with phorbol ester or THP-1 with gamma interferon had no effect on their sensitivity to pneumolysin. However, a significant decrease in the potency of pneumolysin against U937 cells followed gamma interferon treatment. The Hill slopes of the inhibition curves were greater than unity, indicating that pneumolysin may act with positive cooperativity. Analysis of pneumolysin-treated THP-1 cells by electron microscopy revealed membrane lesions of between 100 and 200 nm in diameter. 相似文献