Objective To investigate the feasibility of acquiring the similar homogeneous enhancement using bolus-tracking techniques with shortened respiratory time in prospectively electrocardiogram-gated high-pitch spiral acqu...Objective To investigate the feasibility of acquiring the similar homogeneous enhancement using bolus-tracking techniques with shortened respiratory time in prospectively electrocardiogram-gated high-pitch spiral acquisition mode (Flash mode) coronary computed tomography angiography (CCTA) compared with test bolus technique. Methods One hundred and eighty-four consecutive patients with mean heart rate ≤65 beats per minute undergoing CCTA were prospectively included in this study. The patients were randomly divided into two groups. Patients in the group A (n=92) instructed to shorten respiratory time received CCTA using bolus-tracking technique with high-pitch spiral acquisition mode (Flash mode), while those in the group B (n=92) underwent CCTA with test bolus technique. The attenuation in the ascending aorta, image noise, contrast-to-noise ratio and radiation doses of the two groups were assessed. Results There were no significant differences in the mean attenuation values in the ascending aorta (483.18±59.07 HU vs. 498.7±83.51 HU, P=0.183), image noise (21.4±4.5 HU vs. 20.9±4.3 HU, P=0.414), contrast-to-noise ratio (12.1±4.2 vs. 13.8±5.1, P=0.31) between the groups A and B. There were no significant differences in the radiation dose of dynamic monitoring scans (0.056±0.026 mSv vs. 0.062±0.018 mSv, P=0.068) and radiation dose of angiography (0.94±0.07 mSv vs. 0.96±0.15 mSv,P=0.926) between the two groups, while 15 mL less contrast material volume was administered in the group A than the group B. Conclusion Bolus-tracking technique with shortened time of respiratory in Flash mode of dual-source CT yields the similar homogeneous enhancement with less contrast material in comparison to the test bolus technique.展开更多
Purpose: The main objective of the study was to evaluate the effect of air gaps of 0 - 5.0 cm between bolus and skin for 1.0 cm Superflab bolus on surface dose (DSurf) and depth of maximum dose (dmax) in solid water a...Purpose: The main objective of the study was to evaluate the effect of air gaps of 0 - 5.0 cm between bolus and skin for 1.0 cm Superflab bolus on surface dose (DSurf) and depth of maximum dose (dmax) in solid water and Rando? phantoms. Methods: In this work, the effects of bolus to surface distance on DSurf and variation in dmax were analyzed in a solid water phantom and in an anthropomorphic Rando? phantom for different field sizes, using Gafchromic? EBT films and farmer chamber. Results: For field sizes of 5 × 5 cm2 the DSurf is significantly affected by increasing air gaps greater than 5 mm. For field sizes larger than 10 × 10 cm2, DSurf is nearly the same for air gaps of 0 - 5.0 cm. For small fields and 6 MV photon beam, dmax increases with increasing air gap, while for 10 MV beam and smaller field sizes (i.e. 5 × 5 and 10 × 10 cm2) the dmax first decreases and then increases with the air gaps. For both 3DCRT and IMRT plans on Rando?, DSurf reduction is more prominent with increasing air gaps. Conclusion: For field sizes larger than 10 × 10 cm2 DSurf is largely unaffected by air gaps. However, smaller air gap results in shallower dmax for both 6 MV and 10 MV photon beams at all fields sizes. Special consideration should be taken to reduce air gaps between bolus and skin for field sizes smaller than 10 × 10 cm2 or when surface contour variations are greater or when the bolus covers small area and at the border of the field.展开更多
Fluid mechanical peristaltic transport through esophagus is studied in the paper. A mathematical model has been developed to study the peristaltic transport of a rheological fluid for arbitrary wave shapes and tube le...Fluid mechanical peristaltic transport through esophagus is studied in the paper. A mathematical model has been developed to study the peristaltic transport of a rheological fluid for arbitrary wave shapes and tube lengths. The Ostwald-de Waele power law of a viscous fluid is considered here to depict the non-Newtonian behaviour of the fluid. The model is formulated and analyzed specifically to explore some important information concerning the movement of food bolus through esophagus. The analysis is carried out by using the lubrication theory. The study is particularly suitable for the cases where the Reynolds number is small. The esophagus is treated as a circular tube through which the transport of food bolus takes place by periodic contraction of the esophageal wall. Variation of different variables concerned with the transport phenomena such as pressure, flow velocities, particle trajectory, and reflux is investigated for a single wave as well as a train of periodic peristaltic waves. The locally variable pressure is seen to be highly sensitive to the flow index ＂n＂. The study clearly shows that continuous fluid transport for Newtonian/rheological fluids by wave train propagation is more effective than widely spaced single wave propagation in the case of peristaltic movement of food bolus in the esophagus.展开更多
Chief ComponentsPenis and testes of the ursine seal(Penis etTestes Callorhini)Penis of the deer(Penis Cervi)Penis and testes of the dog(Penis et TestesCanis)
AIM: To assess the impact of bolus volume on the characteristics of small intestinal (SI) impedance signals.METHODS: Concurrent SI manometry-impedance measurements were performed on 12 healthy volunteers to assess the...AIM: To assess the impact of bolus volume on the characteristics of small intestinal (SI) impedance signals.METHODS: Concurrent SI manometry-impedance measurements were performed on 12 healthy volunteers to assess the pattern of proximal jejunal fluid bolus movement over a 14 cm-segment.Each subject was given 34 boluses of normal saline (volume from 1 to 30 mL) via the feeding tube placed immediately above the proximal margin of the studied segment.A bolus-induced impedance event occurred if there was > 12% impedance drop from baseline,over ≥ 3 consecutive segments within 10 s of bolus injection.A minor or major imped-ance event was defined as a duration of impedance drop < 60 s or ≥ 60 s,respectively.RESULTS: The minimum volume required for a detectable SI impedance event was 2 mL.A direct linear relationship between the SI bolus volume and the occurrence of impedance events was noted until SI bolus volume reached 10 mL,a volume which always produced an impedance flow event.There was a moderate correlation between the bolus volume and the duration of impedance drop (r = 0.63,P < 0.0001) and the number of propagated channels (r = 0.50,P < 0.0001).High volume boluses were associated with more major impedance events (≥ 10 mL boluses = 63%,3 mL boluses = 17%,and < 3 mL boluses = 0%,P = 0.02).CONCLUSION: Bolus volume had an impact on the type and length of propagation of SI impedance events and a threshold of 2 mL is required to produce an event.展开更多
AIM: To study the relationship between the patterns of postprandial peristalsis and transduodenal bolus transport in healthy subjects. METHODS: Synchronous recording of chyme transport and peristaltic activity was per...AIM: To study the relationship between the patterns of postprandial peristalsis and transduodenal bolus transport in healthy subjects. METHODS: Synchronous recording of chyme transport and peristaltic activity was performed during the fasting state and after administration of a test meal using a special catheter device with cascade configuration of impedance electrodes and solid-state pressure transducers. The catheter was placed into the duodenum, where the f irst channel was located in the f irst part of the duodenum and the last channel at the duodenojejunal junction. After identif ication of previously def ined chyme transport patterns the associated peristaltic patterns were analyzed. RESULTS: The interdigestive phase 3 complex was reliably recorded with both techniques. Of 497 analyzed impedance bolus transport events, 110 (22%) were short-spanned propulsive, 307 (62%) long-spanned propulsive, 70 (14%) complex propulsive, and 10 (2%) retrograde transport. Short-spanned chyme transports were predominantly associated with stationary or propagated contractions propagated over short distance. Long-spanned and complex chyme transports were predominantly associated with propulsive peristaltic patterns, which were frequently complex and comprised multiple contractions. Propagated double wave contraction, propagated contraction with a clustered contraction, and propagated cluster of contractions have been identif ied to be an integralted part of a peristaltic sequence in human duodenum. CONCLUSION: Combined impedancometry and manometry improves the analysis of the peristaltic patterns that are associated with postprandial transduodenal chymetransport. Postprandial transduodenal bolus transport is regulated by propulsive peristaltic patterns, which are frequently complex but well organized. This f inding should be taken into consideration in the analysis of intestinal motility studies.展开更多
AIM: To look at the relationship between eosinophilic oesophagitis(EO) and food bolus impaction in adults. METHODS: We retrospectively analysed medical records of 100 consecutive patients who presented to our hospital...AIM: To look at the relationship between eosinophilic oesophagitis(EO) and food bolus impaction in adults. METHODS: We retrospectively analysed medical records of 100 consecutive patients who presented to our hospital with oesophageal food bolus obstruction(FBO) between 2012 and 2014. In this cohort, 96 were adults(64% male), and 4 paediatric patients were excluded from the analysis as our centre did not have paediatric gastroenterologists. Eighty-five adult patients underwent emergency gastroscopy. The food bolus was either advanced into the stomach using the push technique or retrieved using a standard retrieval net. Biopsies were obtained in 51 patients from the proximal and distal parts of the oesophagus at initial gastroscopy. All biopsy specimens were assessed and reviewed by dedicated gastrointestinal pathologists at the Department of Pathology, University Hospital Geelong. The diagnosis of EO was defined and established by the presence of the following histological features:(1) peak eosinophil counts > 20/hpf;(2) eosinophil microabscess;(3) superficial layering of eosinophils;(4) extracellular eosinophil granules;(5) basal cell hyperplasia;(6) dilated intercellular spaces; and(7) subepithelial or lamina propria fibrosis. The histology results of the biopsy specimens were accessed from the pathology database of the hospital and recorded for analysis. RESULTS: Our cohort had a median age of 60. Seventeen/51(33%) patients had evidence of EO on biopsy findings. The majority of patients with EO were male(71%). Classical endoscopic features of oesophageal rings, furrows or white plaques and exudates werefound in 59% of patients with EO. Previous episodes of FBO were present in 12/17 patients and 41% had a history of eczema, hay fever or asthma. Reflux oesophagitis and benign strictures were found in 20/34 patients who did not have biopsies. CONCLUSION: EO is present in approximately one third of patients who are admitted with FBO. Biopsies should be performed routinely at index endoscopy in order to pursue this treatable cause of long term morbidity.展开更多
In order to investigate the possibility of using different materials as bolus in radiotherapy, five samples denoted by S2 - S6 were prepared and analyzed by comparison with one available commercial bolus denoted by S1...In order to investigate the possibility of using different materials as bolus in radiotherapy, five samples denoted by S2 - S6 were prepared and analyzed by comparison with one available commercial bolus denoted by S1. Sample S1 was a thermoplastic material from Qfix;S2 was a moldable silicon rubber (RTV-530 from Prochima);S3 and S4 were obtained by adding micrometric particles of Al and Cu respectively (at the same mass concentration of 5.5%);S5 was another moldable silicon rubber (GSP400 from Prochima) and S6 was a mixture of GSP400 and micrometric particles of Cu (at the mass concentration of 5.5%). The measurements of normalized transmitted dose as a function of sample thickness were performed for all samples (S1 - S6) at two values of electron beam energy (6 and 9 MeV) produced by a linear accelerator VARIAN 2100SC. The results showed that the maximum of the normalized transmitted dose of manufactured samples (S2 - S6) is registered at smaller sample thicknesses than for the analyzed commercial bolus (sample S1). The smallest sample thickness corresponding to normalized maximum point dose is obtained for sample S2 (RTV-530). Measurements performed for electron beam energy of 6 and 9 MeV have proven the possibility of using the manufactured samples as bolus in radiotherapy.展开更多
Background/Aims: High-resolution oesophageal manometry utilises water swallows to evaluate oesophageal function. However, small volumes of water are not representative of normal eating and as a result often produce no...Background/Aims: High-resolution oesophageal manometry utilises water swallows to evaluate oesophageal function. However, small volumes of water are not representative of normal eating and as a result often produce normal manometry studies in patients with dysphagia. This study sets out to establish optimal diagnostic thresholds for semi-solid solid swallows and evaluate their ability to uncover motility abnormalities in patients with motility disorders. Method: Manometry was performed using ten 5-mL single water swallows followed by two semi-solid and two solid swallows in the upright position. Normative values for the adjunctive tests were obtained from patient controls while patients with major motility disorders were used to establish the optimal diagnostic thresholds. Diagnostic thresholds identified were prospectively tested in patients with normal water swallows but oesophagus related symptoms and in those with minor and major motility disorders. Results: Normal values for semi-solid and solid were determined in patient controls (n = 100). Development of diagnostic thresholds included 120 patients with major motility disorders. Optimal diagnostic thresholds identified for oesophagogastric junction dysfunction in semi-solid and solid swallows (IRP > 15.5 mmHg). Hypercontractilty and spasm used existing thresholds (>8000 mmHg-s-cm and < 4.5 s, respectively) but modified frequency of ≥50% of adjunctive swallows. Diagnostic thresholds were applied to symptomatic patients with normal water swallows (n = 70) identifying 12/70 (17%) to have abnormal adjunctive swallows. One of 30 patients (3%) with ineffective motility had abnormal adjunctive swallow and 12 patients with oesophageal spasm, oesophagogastric junction obstruction, and hypercontractility had abnormal adjunctive swallows that moved them up the motility disorder hierarchy. Conclusions: Semi-solid and solid challenge increase diagnostic yield of motility disorders.展开更多
Background: Whether premature infants should be fed by bolus or continuous gavage feeding, is still a matter of debate. A recent Cochrane analysis revealed no difference. Study design and methods: We carried out a ran...Background: Whether premature infants should be fed by bolus or continuous gavage feeding, is still a matter of debate. A recent Cochrane analysis revealed no difference. Study design and methods: We carried out a randomized controlled trial in premature infants on continuous versus bolus nasogastric tube feeding, to search for differences with respect to number of incidents, growth, and time to reach full oral feeding. In total, 110 premature neonates (gestational age 27 - 34 weeks) were randomly assigned to receive either continuous or bolus nasogastric tube feeding. Basic characteristics were comparable in both groups. Results: No significant difference in weight gain could be detected between the two groups, mean weight gain amounting 151.6 (108.9 - 194.3) and 152.4 (102.2 - 202.6) grams per week in the continuous and bolus group, respectively. No significant differences were found between both groups in the time needed to achieve full oral feeding (8 oral feedings per day), full oral feeding being achieved at day 31 (range 19 - 43) and day 29 (range 18 - 40) of life in the continuous and bolus group, respectively. We also found no significant differences in the number of 'incident-days' (three or more incidents a day): 3.5 (0 - 9) versus 2.7 (0 - 6.5) days in the continuous and bolus group, respectively. Conclusion: No significant differences were found in weight gain, time to achieve full oral feeding and number of incident-days between preterm infants enterally fed by nasogastric tube, according to either the bolus or continuous method.展开更多
Albendazole is a benzimidazole derivative with broad spectrum of activity against nematodes and cestodes infections in animals. Bulk of the needed drugs in West African sub-region is imported and adulteration in drug ...Albendazole is a benzimidazole derivative with broad spectrum of activity against nematodes and cestodes infections in animals. Bulk of the needed drugs in West African sub-region is imported and adulteration in drug trade is common. This study was aimed at examining the quality of nine brands of veterinary albendazole boluses commonly used in Nigeria. Bolus weight uniformity, assay, hardness, friability, disintegration time, and dissolution profiles of the brands （250 mg/bolus） were tested according to the official specifications. All the brands tested failed bolus weight uniformity test except brands C and H. The percent albendazole in brands A, B, C and F were within official specification whereas D, E, G, H and I failed. None of the brands passed hardness test. All the products passed friability test except brand E. All the test brands disintegrated within the specified time except B and H. Only brands B, C, E and I passed the dissolution test. Consequently, only brands B and C could be interchanged with the reference. There is need for routine quality control and post market surveillance of veterinary drugs in Nigeria.展开更多
基金Supported by the Ministry of Science and Technology of Inner Mongolia, China (20110504)
文摘Objective To investigate the feasibility of acquiring the similar homogeneous enhancement using bolus-tracking techniques with shortened respiratory time in prospectively electrocardiogram-gated high-pitch spiral acquisition mode (Flash mode) coronary computed tomography angiography (CCTA) compared with test bolus technique. Methods One hundred and eighty-four consecutive patients with mean heart rate ≤65 beats per minute undergoing CCTA were prospectively included in this study. The patients were randomly divided into two groups. Patients in the group A (n=92) instructed to shorten respiratory time received CCTA using bolus-tracking technique with high-pitch spiral acquisition mode (Flash mode), while those in the group B (n=92) underwent CCTA with test bolus technique. The attenuation in the ascending aorta, image noise, contrast-to-noise ratio and radiation doses of the two groups were assessed. Results There were no significant differences in the mean attenuation values in the ascending aorta (483.18±59.07 HU vs. 498.7±83.51 HU, P=0.183), image noise (21.4±4.5 HU vs. 20.9±4.3 HU, P=0.414), contrast-to-noise ratio (12.1±4.2 vs. 13.8±5.1, P=0.31) between the groups A and B. There were no significant differences in the radiation dose of dynamic monitoring scans (0.056±0.026 mSv vs. 0.062±0.018 mSv, P=0.068) and radiation dose of angiography (0.94±0.07 mSv vs. 0.96±0.15 mSv,P=0.926) between the two groups, while 15 mL less contrast material volume was administered in the group A than the group B. Conclusion Bolus-tracking technique with shortened time of respiratory in Flash mode of dual-source CT yields the similar homogeneous enhancement with less contrast material in comparison to the test bolus technique.
文摘Purpose: The main objective of the study was to evaluate the effect of air gaps of 0 - 5.0 cm between bolus and skin for 1.0 cm Superflab bolus on surface dose (DSurf) and depth of maximum dose (dmax) in solid water and Rando? phantoms. Methods: In this work, the effects of bolus to surface distance on DSurf and variation in dmax were analyzed in a solid water phantom and in an anthropomorphic Rando? phantom for different field sizes, using Gafchromic? EBT films and farmer chamber. Results: For field sizes of 5 × 5 cm2 the DSurf is significantly affected by increasing air gaps greater than 5 mm. For field sizes larger than 10 × 10 cm2, DSurf is nearly the same for air gaps of 0 - 5.0 cm. For small fields and 6 MV photon beam, dmax increases with increasing air gap, while for 10 MV beam and smaller field sizes (i.e. 5 × 5 and 10 × 10 cm2) the dmax first decreases and then increases with the air gaps. For both 3DCRT and IMRT plans on Rando?, DSurf reduction is more prominent with increasing air gaps. Conclusion: For field sizes larger than 10 × 10 cm2 DSurf is largely unaffected by air gaps. However, smaller air gap results in shallower dmax for both 6 MV and 10 MV photon beams at all fields sizes. Special consideration should be taken to reduce air gaps between bolus and skin for field sizes smaller than 10 × 10 cm2 or when surface contour variations are greater or when the bolus covers small area and at the border of the field.
基金the Council of Scientific and Industrial Research (CSIR) of New Delhi for awarding him a scientific research fund
文摘Fluid mechanical peristaltic transport through esophagus is studied in the paper. A mathematical model has been developed to study the peristaltic transport of a rheological fluid for arbitrary wave shapes and tube lengths. The Ostwald-de Waele power law of a viscous fluid is considered here to depict the non-Newtonian behaviour of the fluid. The model is formulated and analyzed specifically to explore some important information concerning the movement of food bolus through esophagus. The analysis is carried out by using the lubrication theory. The study is particularly suitable for the cases where the Reynolds number is small. The esophagus is treated as a circular tube through which the transport of food bolus takes place by periodic contraction of the esophageal wall. Variation of different variables concerned with the transport phenomena such as pressure, flow velocities, particle trajectory, and reflux is investigated for a single wave as well as a train of periodic peristaltic waves. The locally variable pressure is seen to be highly sensitive to the flow index ＂n＂. The study clearly shows that continuous fluid transport for Newtonian/rheological fluids by wave train propagation is more effective than widely spaced single wave propagation in the case of peristaltic movement of food bolus in the esophagus.
文摘Chief ComponentsPenis and testes of the ursine seal(Penis etTestes Callorhini)Penis of the deer(Penis Cervi)Penis and testes of the dog(Penis et TestesCanis)
基金Supported by The National Health and Medical Research Council of Australia
文摘AIM: To assess the impact of bolus volume on the characteristics of small intestinal (SI) impedance signals.METHODS: Concurrent SI manometry-impedance measurements were performed on 12 healthy volunteers to assess the pattern of proximal jejunal fluid bolus movement over a 14 cm-segment.Each subject was given 34 boluses of normal saline (volume from 1 to 30 mL) via the feeding tube placed immediately above the proximal margin of the studied segment.A bolus-induced impedance event occurred if there was > 12% impedance drop from baseline,over ≥ 3 consecutive segments within 10 s of bolus injection.A minor or major imped-ance event was defined as a duration of impedance drop < 60 s or ≥ 60 s,respectively.RESULTS: The minimum volume required for a detectable SI impedance event was 2 mL.A direct linear relationship between the SI bolus volume and the occurrence of impedance events was noted until SI bolus volume reached 10 mL,a volume which always produced an impedance flow event.There was a moderate correlation between the bolus volume and the duration of impedance drop (r = 0.63,P < 0.0001) and the number of propagated channels (r = 0.50,P < 0.0001).High volume boluses were associated with more major impedance events (≥ 10 mL boluses = 63%,3 mL boluses = 17%,and < 3 mL boluses = 0%,P = 0.02).CONCLUSION: Bolus volume had an impact on the type and length of propagation of SI impedance events and a threshold of 2 mL is required to produce an event.
基金Supported by a grant of the University of Aachen "START-Project"
文摘AIM: To study the relationship between the patterns of postprandial peristalsis and transduodenal bolus transport in healthy subjects. METHODS: Synchronous recording of chyme transport and peristaltic activity was performed during the fasting state and after administration of a test meal using a special catheter device with cascade configuration of impedance electrodes and solid-state pressure transducers. The catheter was placed into the duodenum, where the f irst channel was located in the f irst part of the duodenum and the last channel at the duodenojejunal junction. After identif ication of previously def ined chyme transport patterns the associated peristaltic patterns were analyzed. RESULTS: The interdigestive phase 3 complex was reliably recorded with both techniques. Of 497 analyzed impedance bolus transport events, 110 (22%) were short-spanned propulsive, 307 (62%) long-spanned propulsive, 70 (14%) complex propulsive, and 10 (2%) retrograde transport. Short-spanned chyme transports were predominantly associated with stationary or propagated contractions propagated over short distance. Long-spanned and complex chyme transports were predominantly associated with propulsive peristaltic patterns, which were frequently complex and comprised multiple contractions. Propagated double wave contraction, propagated contraction with a clustered contraction, and propagated cluster of contractions have been identif ied to be an integralted part of a peristaltic sequence in human duodenum. CONCLUSION: Combined impedancometry and manometry improves the analysis of the peristaltic patterns that are associated with postprandial transduodenal chymetransport. Postprandial transduodenal bolus transport is regulated by propulsive peristaltic patterns, which are frequently complex but well organized. This f inding should be taken into consideration in the analysis of intestinal motility studies.
文摘AIM: To look at the relationship between eosinophilic oesophagitis(EO) and food bolus impaction in adults. METHODS: We retrospectively analysed medical records of 100 consecutive patients who presented to our hospital with oesophageal food bolus obstruction(FBO) between 2012 and 2014. In this cohort, 96 were adults(64% male), and 4 paediatric patients were excluded from the analysis as our centre did not have paediatric gastroenterologists. Eighty-five adult patients underwent emergency gastroscopy. The food bolus was either advanced into the stomach using the push technique or retrieved using a standard retrieval net. Biopsies were obtained in 51 patients from the proximal and distal parts of the oesophagus at initial gastroscopy. All biopsy specimens were assessed and reviewed by dedicated gastrointestinal pathologists at the Department of Pathology, University Hospital Geelong. The diagnosis of EO was defined and established by the presence of the following histological features:(1) peak eosinophil counts > 20/hpf;(2) eosinophil microabscess;(3) superficial layering of eosinophils;(4) extracellular eosinophil granules;(5) basal cell hyperplasia;(6) dilated intercellular spaces; and(7) subepithelial or lamina propria fibrosis. The histology results of the biopsy specimens were accessed from the pathology database of the hospital and recorded for analysis. RESULTS: Our cohort had a median age of 60. Seventeen/51(33%) patients had evidence of EO on biopsy findings. The majority of patients with EO were male(71%). Classical endoscopic features of oesophageal rings, furrows or white plaques and exudates werefound in 59% of patients with EO. Previous episodes of FBO were present in 12/17 patients and 41% had a history of eczema, hay fever or asthma. Reflux oesophagitis and benign strictures were found in 20/34 patients who did not have biopsies. CONCLUSION: EO is present in approximately one third of patients who are admitted with FBO. Biopsies should be performed routinely at index endoscopy in order to pursue this treatable cause of long term morbidity.
文摘In order to investigate the possibility of using different materials as bolus in radiotherapy, five samples denoted by S2 - S6 were prepared and analyzed by comparison with one available commercial bolus denoted by S1. Sample S1 was a thermoplastic material from Qfix;S2 was a moldable silicon rubber (RTV-530 from Prochima);S3 and S4 were obtained by adding micrometric particles of Al and Cu respectively (at the same mass concentration of 5.5%);S5 was another moldable silicon rubber (GSP400 from Prochima) and S6 was a mixture of GSP400 and micrometric particles of Cu (at the mass concentration of 5.5%). The measurements of normalized transmitted dose as a function of sample thickness were performed for all samples (S1 - S6) at two values of electron beam energy (6 and 9 MeV) produced by a linear accelerator VARIAN 2100SC. The results showed that the maximum of the normalized transmitted dose of manufactured samples (S2 - S6) is registered at smaller sample thicknesses than for the analyzed commercial bolus (sample S1). The smallest sample thickness corresponding to normalized maximum point dose is obtained for sample S2 (RTV-530). Measurements performed for electron beam energy of 6 and 9 MeV have proven the possibility of using the manufactured samples as bolus in radiotherapy.
文摘Background/Aims: High-resolution oesophageal manometry utilises water swallows to evaluate oesophageal function. However, small volumes of water are not representative of normal eating and as a result often produce normal manometry studies in patients with dysphagia. This study sets out to establish optimal diagnostic thresholds for semi-solid solid swallows and evaluate their ability to uncover motility abnormalities in patients with motility disorders. Method: Manometry was performed using ten 5-mL single water swallows followed by two semi-solid and two solid swallows in the upright position. Normative values for the adjunctive tests were obtained from patient controls while patients with major motility disorders were used to establish the optimal diagnostic thresholds. Diagnostic thresholds identified were prospectively tested in patients with normal water swallows but oesophagus related symptoms and in those with minor and major motility disorders. Results: Normal values for semi-solid and solid were determined in patient controls (n = 100). Development of diagnostic thresholds included 120 patients with major motility disorders. Optimal diagnostic thresholds identified for oesophagogastric junction dysfunction in semi-solid and solid swallows (IRP > 15.5 mmHg). Hypercontractilty and spasm used existing thresholds (>8000 mmHg-s-cm and < 4.5 s, respectively) but modified frequency of ≥50% of adjunctive swallows. Diagnostic thresholds were applied to symptomatic patients with normal water swallows (n = 70) identifying 12/70 (17%) to have abnormal adjunctive swallows. One of 30 patients (3%) with ineffective motility had abnormal adjunctive swallow and 12 patients with oesophageal spasm, oesophagogastric junction obstruction, and hypercontractility had abnormal adjunctive swallows that moved them up the motility disorder hierarchy. Conclusions: Semi-solid and solid challenge increase diagnostic yield of motility disorders.
文摘Background: Whether premature infants should be fed by bolus or continuous gavage feeding, is still a matter of debate. A recent Cochrane analysis revealed no difference. Study design and methods: We carried out a randomized controlled trial in premature infants on continuous versus bolus nasogastric tube feeding, to search for differences with respect to number of incidents, growth, and time to reach full oral feeding. In total, 110 premature neonates (gestational age 27 - 34 weeks) were randomly assigned to receive either continuous or bolus nasogastric tube feeding. Basic characteristics were comparable in both groups. Results: No significant difference in weight gain could be detected between the two groups, mean weight gain amounting 151.6 (108.9 - 194.3) and 152.4 (102.2 - 202.6) grams per week in the continuous and bolus group, respectively. No significant differences were found between both groups in the time needed to achieve full oral feeding (8 oral feedings per day), full oral feeding being achieved at day 31 (range 19 - 43) and day 29 (range 18 - 40) of life in the continuous and bolus group, respectively. We also found no significant differences in the number of 'incident-days' (three or more incidents a day): 3.5 (0 - 9) versus 2.7 (0 - 6.5) days in the continuous and bolus group, respectively. Conclusion: No significant differences were found in weight gain, time to achieve full oral feeding and number of incident-days between preterm infants enterally fed by nasogastric tube, according to either the bolus or continuous method.
文摘Albendazole is a benzimidazole derivative with broad spectrum of activity against nematodes and cestodes infections in animals. Bulk of the needed drugs in West African sub-region is imported and adulteration in drug trade is common. This study was aimed at examining the quality of nine brands of veterinary albendazole boluses commonly used in Nigeria. Bolus weight uniformity, assay, hardness, friability, disintegration time, and dissolution profiles of the brands （250 mg/bolus） were tested according to the official specifications. All the brands tested failed bolus weight uniformity test except brands C and H. The percent albendazole in brands A, B, C and F were within official specification whereas D, E, G, H and I failed. None of the brands passed hardness test. All the products passed friability test except brand E. All the test brands disintegrated within the specified time except B and H. Only brands B, C, E and I passed the dissolution test. Consequently, only brands B and C could be interchanged with the reference. There is need for routine quality control and post market surveillance of veterinary drugs in Nigeria.
