bluuebunny/crossref_metadata_2025_split huggingface dataset:
Recruitment of a Large Community of Pediatricians in a Collaborative Research Project
Authors: Nazarian Lawrence F. , Maiman Lois A. , Becker Marshall H. 
Published: November 2007

To investigate the effects of an educational program on the compliance-enhancing behavior of pediatricians and the subsequent regimen adherence of their patients, it was necessary to enlist the participation of a large number of pediatric practitioners. The physicians had to be motivated to attend two evenings of tutorial training; to enroll their patients in the project; and to complete detailed study documents. Ultimately, 90 of the 97 pediatricians practicing in the community took part. The following factors are felt to have contributed to the widespread participation of the pediatricians: 1) the subject was interesting and of relevance to clinical practice; 2) the study was designed so as not to interfere with office routine; 3) major demands were not made on the patients; 4) due consideration was given to the value of the physicians' participation; and 5) communication between the investigators and the practitioners was facilitated by a liaison pediatrician.
Early Presentation with a Desmoid Tumor
Authors: Halata Michael S. , Miller Javier , Stone Richard K. 
Published: November 2007

A 14-year-old patient who was eventually found to have Gardner syndrome initially presented at the age of 3 years with a desmoid tumor involving the scalp. A careful review of the family history revealed a high incidence of colonic cancer, which prompted endoscopic evaluation of the patient. The discovery of adenomatous polyps in the colon confirmed the diagnosis of Gardner syndrome. In patients with hard or soft tissue tumors, the possibility of Gardner syndrome should be kept in mind, and a thorough family history taken. Early diagnosis may prevent malignant transformation of colonic polyps.
Nasal Glioma
Authors: Puppala Bhagya , Mangurten Henry H. , McFadden John , Lygizos Nicholas , Taxy Jerome , Pellettiere Edmund 
Published: November 2007

Nasal gliomas are benign congenital midline tumors with the potential for intracranial extension. They are most commonly seen in neonates and children but rarely in adults. The treatment of choice is surgical excision. Inadequate primary excision results in a 4 to 10 percent recurrence. Hence, a thorough preoperative evaluation is essential to delineate the exact site and extension of the tumor and to plan the appropriate surgical approach. Computerized tomographic (CT) scans are useful in visualizing bony defects, but are not well suited for soft tissue imaging. Magnetic resonance imaging (MRI) offers superior soft tissue contrast, without ionizing radiation. This is a report of a neonate with unexplained early respiratory distress. On day 5, a soft nasal mass became apparent. CT scans were inconclusive, so MRI scan was used to demonstrate intracranial extension. MRI is superior for imaging brain tissue, so it should be used preferentially to delineate intracranial extension and to help guide the surgical approach.
Comparison of Urine Dipstick, Microscopy, and Culture for the Detection of Bacteriuria in Children
Authors: Goldsmith Barbara M. , Campos Joseph M. 
Published: November 2007

The authors compared dipstick tests for leukocyte esterase and nitrite and microscopic examination of urinary sediment with urine culture to assess whether the former tests could reliably rule out bacteriuria in specimens from children. The authors studied urine specimens from 1010 infants and children younger than age 18. Compared with culture at ≥105 colony forming units (cfu)/ml, the sensitivities of leukocyte esterase, nitrite, and microscopic examination of white blood cells (≥5 wbc/hpf) or bacteria (in at least moderate numbers) were 76 percent, 29 percent, 82 percent, and 80 percent, respectively. The specificities of the same tests were 81 percent, 99 percent, 81 percent, and 83 percent, respectively. Compared with culture at ≥104 cfu/ml, the sensitivities of the tests were 64 percent, 21 percent, 64 percent, and 59 percent; the specificities were 82 percent, 99 percent, 81 percent, and 83 percent, respectively. The negative predictive values of leukocyte esterase and microscopic examinations of urinary sediment for white blood cells and bacteria were all 95 percent (≥104 cfu/ml) or 98 percent (≥105 cfu/ml). The authors conclude that the leukocyte esterase test is as accurate as sediment microscopy in identifying urine specimens from infants and children harboring <10 4 or <105 cfu/ml.
Bacterial Meningitis—An Update
Authors: Marks Melvin I. 
Published: November 2007

This report emphasizes new clinical information about bacterial meningitis in infants and children. Important elements of diagnosis include examination for the presence of shock and increased intracranial pressure. In such cases, initial treatment should focus on appropriate fluid therapy, administration of oxygen, reduction of intracranial pressure and use of corticosteroids. Currently, antibiotics of choice include ampicillin plus either cefotaxime or ceftriaxone in young infants, and one of these cephalosporins in older patients (beyond 3 months of age). Shorter durations of therapy (5 to 7 days for meningococcus, 7 days for haemophilus and 7-10 days for pneumococcus) are now commonly employed. In many centers, dexamethasone is started before the first dose of antibiotic and continued for 4 days to reduce neurologic and audiologic sequelae. Future trends will include studies of endotoxin neutralizers and non-steroidal anti-inflammatory drugs to reduce further tissue injury in meningitis. Prevention of meningitis is the ultimate goal. Since Haemophilus influenzae vaccination can now begin at 2 months, this approach may bring important results soon.
An intervention for enhancing children's understanding of jokes and riddles
Authors: Ezell Helen K. , Jarzynka Melanie A. 
Published: November 2007

An intervention was conducted for teaching children a strategy for understanding and explaining the humour in lexical jokes. Two typical 7-year-olds and two students with learning disabilities, ages 9 and 11, participated in the training. A multiple probe design across joke sets and across children was used. Results showed that all children mastered the strategy and learned to explain lexical jokes. Limited generalization of this strategy to untrained jokes occurred; however, generalization increased significantly after children gained more knowledge of multiple word meanings through follow-up semantic training. Clinical implica tions are discussed.
Late-Holocene changes in sea level and environment on eastern Cape Breton Island, Nova Scotia, Canada
Authors: Miller Kristina R. , Livingstone Daniel A. 
Published: November 2007

The late-Holocene history of a coastal basin in Otter Harbour on the Great Bras D'Or of Cape Breton Island, Nova Scotia was reconstructed using micro- and macrofossils. The pollen stratigraphy shows a decrease in oak and pine pollen percentages around 4000 BP, while Tsuga pollen reaches a maximum. Over the last 1000 years, genera of the mixed hardwood forest have declined while boreal genera have increased, suggesting climatic cooling in the region. Human influence from 400 BP to the present is evidenced by increased pteridophyte spores and pollen of Rumex, Gramineae, and Ambrosia. Siliceous microfossils indicate that sea level in the Great Bras D'Or rose over the last 4000 years to 1.5 m below present level at 950 BP. This rate of sea-level rise, 16 cm per century, falls within the regional range of relative sea-level rise in the Maritimes of 10-30 cm per century for the last several thousand years. However, this long-term rate in the Maritimes is less than the rate of 30-35 cm per century determined from local tide gauges over the last hundred years. The discrepancy between these two rates can probably be attributed to recent changes in the eustatic or tectonic components of sea- level rise in this region.
Impact of Euro-American settlement on a riparian landscape in northeast Iowa, midwestem USA: an integrated approach based on historical evidence, floodplain sediments, fossil pollen, plant macrofossils and insects
Authors: Baker R.G. , Schwert D.P. , Bettis E.A. , Chumbley C.A. 
Published: November 2007

European settlement and attendant forest clearance and agricultural activities in northeastern Iowa caused changes in the landscape, vegetation, insect fauna and water quality unequalled in rate and magnitude since the melting of Wisconsinan glaciers. Historical documents show that the upper part of the Roberts Creek drainage basin was settled between AD 1840 and 1856, and the area was under intensive cultivation by 1880. Extensive soil erosion beginning at this time resulted in increased runoff and more frequent flooding; aggradation rates increased by one to two orders of magnitude over those in presettlement times, and the entire floodplain was covered with up to 1 m of sediment. Channel widening between about 1880 and 1930 allowed the stream to accommodate greater floods, overbank deposition decreased, and further deposits were restricted mostly to the channel belt. The presettlement vegetation was a stable mix of wet meadows and riparian shrubs on the floodplain, a rich aquatic community in the stream, and oak savanna on the valley walls and upland. Disturbance from soil erosion, floodplain erosion and floodplain deposition almost completely replaced both lowland and upland communities with ruderal (disturbed ground) plants, many of them introduced weeds. Regional insect communities were simultaneously affected by changes in land use. The presettlement aquatic beetle fauna was dominated by species of dryopoid beetles that today inhabit only streams of high water quality. Terrestrial beetle taxa included species of undisturbed grasslands and riparian forest. The changes in the landscape resulted in a decrease in the diversity of terrestrial beetle taxa and caused the near total elimination of dryopoid beetles in stream waters. Dominating the historic assemblages are beetles associated with dung, polluted waters and cultivated plants, including host-specific immigrant beetle species that are associated with immigrant plant species.
A palaeolimnological test of the influence of Norway spruce (Picea abies) immigration on lake-water acidity
Authors: Korsman Tom , Renberg Ingemar , Anderson N. John 
Published: November 2007

The effect of recent land use and subsequent vegetation changes per se on surface-water acidity is difficult to ascertain because of the complicating factor of enhanced levels of anthropogenic acid deposition that occurs at the same time as land-use changes. Expansion of conifers is a major contemporary vegetation change in Sweden and other countries. The immigration of Norway spruce (Picea abies (L.) Karst.) into Sweden about 3000 years ago provides, however, a suitable means of assessing the acidification ability of spruce per se on surface waters. Pollen analysis was used to identify the arrival of spruce in the catchments of eight acid-sensitive Swedish boreal-forest lakes. pH and dissolved organic carbon (DOC) were inferred from diatom assemblages for time periods covering some hundred years before and after the establishment of spruce. Redundancy analysis (RDA) was used to assess whether catchment vegetation had significant effects on the diatom assemblages. At four sites there were significant changes in the diatom assemblages associated with the arrival of spruce, but none of the lakes acidified. At three sites, however, diatom- inferred DOC increased with the arrival of spruce, probably as a result of the accumulation of raw humus.
Sewage history in the anoxic sediments of the fjord Nordåsvannet, western Norway: (I) dating and trace-metal accumulation
Authors: Paetzel Matthias , Schrader Hans , Croudace Ian 
Published: November 2007

A combined study involving lamina counting, 210Pb and the fallout- 137Cs dating techniques were used to date two sediment cores with intact sediment-water interfaces from the anoxic fjord Nordåsvannet. Averaged sedimentation rates, determined from radiometric measurements, range from 0.4 to 2.1mm yr-1 over the core with a higher rate at the top. The available lamina data support the sedimentation rate estimates made from radiometric measurements. An increase was found in trace-metal concentrations (Zn: 90-807 ppm ; Cu: 30-176 ppm and Pb: 40-225 ppm) and mass accumulation rates (MAR; Zn: 0.003-0.10 g m2 yr -1, Cu: 0.001-0.02 g m2 yr-1 and Pb: 0.002-0.02 g m2 yr-1) across the upper 5 cm of the sediments. This increase coincides with the introduction of sewage effluent through two deep outlets at 40m water depth into the fjord at Fjøsanger and Skjold in 1969. The MAR suggest that the enhanced sewage supply has caused the metal enrichment in the Nordåsvannet bottom sediments after 1969.
Meta-analytic stimulus for changes in clinical trials
Authors: Harvard TC Chalmers , Lau J. 
Published: November 2007

The advent of meta-analysis, especially when performed cumulatively, raises many questions about how best to approach the conduct of clinical trials in the evaluation of new treatments. We need to be assured that bias is minimized by proper experimental procedures and that clinical data, on the whole and in subgroups, are presented so that they can be effectively combined in meta-analysis. We need to re-examine the idea that we should not start a randomized control trial unless sufficient patients are available to avoid reasonable type I and II errors. Meta-analyses will come to the rescue, provided trials continue to be published at the present rate. We need to perform meta-analyses before undertaking each additional trial, and we need to base estimates of trial size on past data as well as the expected control rates and the differences we do not want to miss. In clinical trials of new interventions attempting to disprove the null hypothesis may be inappropriate because past data so often suggest or even establish that it is not true. Furthermore we need to recognize that trends ( p > 0.05) can be both clinically and statistically important, and we must abandon the notion that if p is not < 0.05, the treatment is ineffective. In performing meta-analyses we need to worry about minimizing bias and error and consider the differences between the random and fixed effects models and between reporting results as an odds ratio versus difference in risk, with the control rates given. Experiences with cumulative meta-analysis have required that we think about all of these problems.
The Importance of Considering Trial Design When Interpreting Clinical Trial Results
Authors: Reiffel James A. 
Published: November 2007

Background: In recent decades, clinical trials have played an increasingly important role in determining how we practice. Trial results proving that a clinical finding poses risk have led to interventions that try to reduce risk. Clinical trials proving that a particular therapy provides better outcome than another therapy have changed the therapies we now use. Unfortunately, the results of clinical trials are too often affected by biases or design issues that may overtly or covertly alter the results or the way they should really be used. In addition, these biases and design and analysis issues are rarely evident in the abstract sections or key figures and tables in the publications reporting the trials, which may be all the busy physician either reads or remembers. Methods and Materials: This manuscript discusses the issues involved in optimally under standing clinical trial design and interpretation so that practitioners can better understand how to intelligently read and apply trial results to clinical practice. Conclusions: Clinical trial results can not be properly applied without consideration of trial design features and intertrial comparisons.
Digoxin's Minimal Inotropic Effect Is Not Limited by Sodium—Calcium Exchange in the Intact Immature Rabbit Heart
Authors: Phoon Colin K. , Wu Shao T. , Parmley William W. 
Published: November 2007

Background: In the intact immature heart, how much digoxin can drive sodium-calcium exchange has not been studied in the context of sodium-calcium exchanger abundance. Methods and Results: The effects of digoxin and low potassium on contractility in the intact, paced and isovolumically contracting immature rabbit heart were studied in both the absence and presence of L-type calcium channel blockade. Without calcium channel block ade, digoxin increased contractility minimally and only at 10-6 M/L. In contrast, low potas sium (2.2 mM/L) substantially increased contractility in all experiments, a result indicating abundant sodium-calcium exchanger activity. During nifedipine-induced calcium channel blockade, digoxin (10-6 M/L) allowed modest recovery of contractility, whereas digoxin and low potassium together allowed complete recovery as assessed by dP/dtmax; however, all hearts so perfused subsequently developed ventricular fibrillation, presumably because of calcium overload. Conclusions: In intact immature rabbit heart, digoxin can drive sodium-calcium exchange and thus increase contractility to only a minimal extent. This effect does not appear to be lim ited by intrinsic exchanger activity, which appears abundant in this preparation. Rather, digoxin's inability to drive the sodium-calcium exchanger may be due to developmental dif ferences in binding to the sodium pump. The sodium-calcium exchanger itself seems capable not only of providing enough intracellular calcium for normal contraction, but also of over loading the myocardium with calcium, despite L-type calcium channel blockade.
Sotalol Is More Powerful Than Propranolol in Suppressing Complex Ventricular Arrhythmias
Authors: Deedwania Prakash C. 
Published: November 2007

Background: Sotalol has combined type II and type III antiarrhythmic properties. Although the β-blocking action of sotalol is thought to contribute to its antiarrhythmic actions, few data are available from direct comparative clinical trials with pure β-blocking drugs. Methods and Results: In this double-blind, randomized, multicenter, placebo-controlled, parallel study, we have compared the antiarrhythmic efficacy and safety of treatment with sotalol vs propranolol in 181 patients with organic heart disease and frequent (> 30 ventricu lar premature complexes [VPCs]/h) repetitive ventricular premature complexes. Eighty-seven were randomized to receive sotalol and 94 received propranolol. The demographic and clini cal characteristics of the two groups were identical, and the majority of patients had coronary artery disease or hypertensive heart disease. Most patients had a long-standing history (> 5 years) of ventricular arrhythmias and, in a significant proportion, antiarrhythmic therapy with other drugs had failed in the past. After withdrawal of all antiarrhythmic drugs and 1 week of placebo, qualified patients were randomized to sotalol (320 mg/day) or propranolol (120 mg/day). Patients not achieving adequate response were given higher doses of sotalol (640 mg/day) or propranolol (240 mg/day). At baseline, both groups had comparable frequency of total VPCs/hour (274/h and 255/h for sotalol and propranolol groups, respectively) which was reduced to 71 VPCs/h and 109/VPCs/h, respectively, at the end of phase 1. At final eval uation there was a significantly greater response to sotalol as demonstrated by 80% reduction in VPCs/hour with sotalol compared with only 50% reduction noted in the propranolol group. Adequate therapeutic response was also achieved in a significantly greater percentage of patients on sotalol compared with propranolol (56% vs 29%. P = .02). Sotalol was also superior to propranolol in suppressing the VT events/day during phase 1 (89% vs 78% reduc tion in VT events/days, P < .05). Sotalol was more effective than propranolol in all subgroups and in patients with heart rate < 75 beats per minute. Conclusions: Sotalol is more powerful than propranolol in suppressing ventricular arrhyth mias documented on Holter recordings. The superiority of sotalol appears to be related to its combined class II and class III antiarrhythmic actions.
Different Effects of Amiodarone and Quinidine on the Homogeneity of Myocardial Refractoriness in Patients With Intraventricular Conduction Delay
Authors: Cui Guanggen , Sager Philip T. , Singh Bramah N. , Sen Luyi 
Published: November 2007

Background: Increases in QT and JT dispersion have been suggested as indicative of a proarrhythmic potential as a result of heterogeneity in myocardial refractoriness, the reduc tion of which by antiarrhythmic agents might be associated with a beneficial effect on the development of serious ventricular arrhythmias. Methods: To test the hypothesis that amiodarone reduces the heter-ogeneity of ventricular refractoriness to a significantly greater extent than quinidine in patients with intraventricu lar conduction defects under treatment for ventricular arrhythmias, the corrected and uncorrected QT and JT intervals and dispersions from 12-lead surface electrocardiograms were determined in 120 patients with intraventricular conduction defects with cardiac arrhythmias before and during treatment with amiodarone (n = 60) and quinidine (n = 60). Rcsults: Amiodarone increased QT from 403 ± 50 ms to 459 ± 47 ms ( P < .001), with a sim ilar increase in the corrected QT interval (QTc) ( P < .001). Amiodarone reduced QT disper sion by 40% ( P < .001), whereas quinidine increased by 18% ( P < .001). The net effects of both drugs were similar for QTc. Amiodarone, but not quinidine, reduced heart rate signifi cantly; amiodarone had no effect on the QRS; but quinidine increased it ( P < .001). Quini dine as well as amiodarone increased the JT and JTc intervals significantly, but the effect of quinidine was quantitatively less striking. Amiodarone decreased the JT dispersion by 33% ( P < .001) and JTc dispersion by 37% ( P < .001). On the other hand, quinidine increased the corresponding values for JT and JTc by 18% ( P < .001) and 21 % ( P < .001), respectively. The overall data on QT and JT dispersions indicate an improvement in the homogeneity of myo cardial refractoriness with amiodarone treatment and the converse with quinidine treatment; this observation is consistent with a lower proarrhythmic propensity and mortality with amio darone than with quinidine. Quinidine increased the QRS interval more than amiodarone, and the data indicate that in patients with intraventricular conduction defects, the monitoring of the JT interval might more accurately reflect changes in myocardial repolarization. Conclusions: Amiodarone and quinidine both increased the corrected and uncorrected QT and JT intervals; amiodarone decreased and quinidine increased the dispersion of these intervals, and these results suggested an improvement in the homogeneity of myocardial refractoriness as a result of amiodarone treatment and the converse as a result of quinidine treatment. Quinidine increased the QTS interval more than amiodarone, and the data indi cate that in patients with intraventricular conduction defects, the monitoring of the JT inter val might more accurately reflect changes in myocardial repolarization.