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11.
12.
Plasmablastic lymphoma is a very rare and recently-described subtype of diffuse large B-cell lymphoma. It has a poor prognosis despite intensive chemotherapy treatment. A 57-year old woman with perianal Crohn's disease receiving azathioprine and infliximab developed this type of lymphoma after a short period of time on the treatment. She also had a hepatitis C virus chronic infection which had not been diagnosed or treated before. There is no solid scientific evidence that either immunomodulators or anti-TNF drugs have a definitive role in the appearance of malignancies, and therefore there are no clear recommendations to limit their use. In these patients, there are some other factors we have to take into account, like the inflammatory bowel disease in itself and its behaviour over time, or the comorbidities of the patient, with special attention to virus infections. In this case report, we will analyse the role of these factors in the development of lymphoproliferative disorders and the recommendations given by experts to avoid their appearance.  相似文献   
13.
beta-Adrenergic blockade after single, oral doses of labetalol or propranolol was evaluated in a double-blind, placebo-controlled study by an isoproterenol sensitivity test and handgrip exercise in 10 healthy men. The tests were performed with subjects resting in a supine position. At the doses used, there was no effect on heart rate and blood pressure in either the resting position or in the isometric exercise phase. It is possible that exercise-induced changes in blood pressure and heart rate were reduced by higher vagal tone in this young group tested in the supine position. Isoproterenol increased heart rate and reduced diastolic blood pressure in a dose-dependent manner. The dose of isoproterenol at which heart rate increased 25 bpm above the resting rate (CD25; 1.36 +/- 0.18 microgram) was of the order of that at which diastolic blood pressure fell 25 mm Hg from baseline (HD25; 1.07 +/- 0.07 microgram). There was a significant positive correlation between CD25 and HD25 in the 10 subjects. Propranolol and labetalol induced a dose-dependent, parallel shift to the right in the dose-response curves of isoproterenol effects on heart rate and diastolic blood pressure, indicating that both drugs are nonselective, competitive antagonists of beta-adrenergic receptors. On the average, propranolol was 17 and 19 times more potent than labetalol in antagonizing the chronotropic and hypotensive actions of isoproterenol, respectively.  相似文献   
14.
Background: Little is known about the electrocardiographic (ECG) QT interval and its variability in malnourished children. Hypothesis: The study of the QT interval and its dispersion in malnourished children was undertaken to determine whether the QT interval and its variability are increased in these children. Methods: In 40 children (20 malnourished and 20 controls) aged 12.2 ± 14.4 months (23 male) a conventional ECG was performed for computing heart rate, heart rate variability, corrected QT interval, and QT-interval dispersion. A blood sample was obtained for measuring hemoblogin, hematocrit, plasma protein, and plasma electrolytic concentrations. Results: Corrected heart rate, heart rate variability, and QT interval were similar in both groups. When compared with the control group, the malnourished children had greater corrected QT-interval dispersion, and that dispersion was more accentuated in the precordial leads. They also had repolarization abnormalities (flattened or inverted T waves and U waves). Hemoglobin, hematocrit, plasma protein, and plasma electrolytic concentrations were lower in the malnourished children. However, the ECG findings showed no statistically significant relationship with either the blood parameters, the severity or type of malnutrition, and the size or the weight of the children. Conclusions: QT-interval dispersion is increased in malnourished children and the dispersion is more accentuated in the precordial leads.  相似文献   
15.
This one-dimensional thin-layer chromatographic method is used for assay of phospholipids in the gastric aspirate of newborns. The solvent mixture (chloroform/hexane/methanol/glacial acetic acid/water, 12/7/4/3/0.3 by vol) completely resolves lecithin, sphingomyelin, phosphatidylinositol, phosphatidylserine, phosphatidylethanolamine, and phosphatidylglycerol. The method is simple, precise, inexpensive, and rapid (chromatographic development takes less than 25 min) and gives high chromatographic resolution. We used this method to determine the lecithin/sphingomyelin densitometric ratio (L/S ratio) and the phosphatidylglycerol percentage in 200 samples of gastric aspirate and found an L/S ratio of 2.5 to be a satisfactory cutoff value for distinguishing fetal lung maturity and immaturity. We confirmed that the presence of phosphatidylglycerol excluded the possibility of respiratory distress.  相似文献   
16.
ObjectiveWe measured iron bioavailability of meals based on wheat flour consumed by a vulnerable population in Latin America.MethodsBioavailability of iron (ferrous sulfate) from fortified noodles, noodle soup, noodle soup eaten with lemonade sweetened with panela (unrefined whole cane sugar), bread alone, and bread consumed with a chamomile infusion sweetened with panela was studied using the double isotopic method in 13 women.ResultsIron bioavailabilities from bread, noodles, and noodle soup were not significantly different (7.4%, 6.3%, and 6.0%, respectively). Iron absorption from noodle soup was significantly higher when given with lemonade (11.0%) compared with absorption of the same meal without lemonade (P < 0.02) or with the absorption of noodles (P < 0.04). Iron absorption of bread given alone or with chamomile infusion sweetened with panela (8%) was not significantly different.ConclusionIron bioavailability of meals based on wheat flour, fortified with ferrous sulfate, is improved when given with lemonade. The consumption of this beverage may be an alternative to further increase the effectiveness of wheat flour fortification in preventing iron deficiency in low-income Latin American populations.  相似文献   
17.

Background

Bundle branch block (BBB) is a difficult diagnosis in the Wolff–Parkinson–White syndrome (WPW). We investigated the clinical implications of BBB that appears after performing an accessory pathway (AP) ablation.

Methods

We studied 199 patients with WPW who were submitted to AP ablation. Thirty (15%) exhibited BBB after the ablation. Twenty-two patients had right BBB and 8 had left BBB. Thirteen patients had right-sided AP and 17 had left-sided AP. They were compared with 82 similar patients without BBB after the AP ablation.

Results

Among the patients with BBB, 86.66% showed delays in the middle part of the QRS in the ECG recorded before ablation vs. 18.29% of the patients without BBB (p < 0.05) (sensitivity 86%, specificity 81%, positive predictive value 67% and negative predictive value 93%). Forty-four percent of the patients with BBB had BBB morphology during orthodromic tachycardia vs. 10% of the patients without BBB (p < 0.05) (sensitivity 44%, specificity 89%, positive predictive value 57% and negative predictive value 82%). No relationship was found between AP location and the site of the BBB. Ejection fraction was normal before (0.61 ± 0.03) and upon completion of follow-up (0.61 ± 0.07). BBB disappeared in 95.3% of the patients.

Conclusions

Delays in the middle portion of the QRS may predict BBB after AP ablation. BBB after performing AP ablation is frequent, transient, benign, and not related to either the ablation lesion location or progression to structural heart disease. BBB after AP ablation may be related to cardiac memory.  相似文献   
18.
An inbred pedigree is described in which three members were affected with FND (Frontonasal Dysplasia). Two of these individuals werz products of a consanguineous mating with an inbreeding coefficient of F = 0.0391. The third affected individual (propositus), was born to a marriage in which the coefficient of inbreeding was 0.0742. The mother of the propositus, whose inbreeding coefficient was 0.0625, had borderline hypertelorism and a broad nose. Several other members of the pedigree who had hypertelorism were products of consanguineous matings. The presence of consanguinity in all individuals affected with a variety of manifestations of FND suggests a genetic mechanism for this malformation.  相似文献   
19.
BACKGROUND: Randomized controlled trials have shown inconsistent responses of childhood pneumonia to the use of vitamin A as an adjunct to the standard treatment of pneumonia. OBJECTIVE: We evaluated the effect of a moderate dose of vitamin A as an adjunct to standard antimicrobial treatment on the duration of respiratory signs in children with pneumonia. DESIGN: Children, aged 2-59 mo, with pneumonia and weight-for-age <50th percentile who had been admitted to the Baca Ortíz Children's Hospital in Quito, Ecuador, were randomly assigned to receive 50,000 IU (aged 2-12 mo) or 100,000 IU (aged >12-59 mo) vitamin A or a placebo. RESULTS: Of the 287 children enrolled, 145 received vitamin A and 142 received placebo. No overall differences were observed between the 2 groups in the duration of signs of pneumonia. Multiple linear regression showed a significant interaction between basal serum retinol concentration and vitamin A group for the time (in h) to remission of respiratory signs (beta = -3.57, SE = 1.09, P = 0.001). Duration of clinical signs was less in children with basal serum retinol concentrations >200 microg/L who received vitamin A supplements than in children with similar concentrations who received placebo (69.9 +/- 49.9 h compared with 131.3 +/- 143.9 h; P = 0.049). CONCLUSIONS: Overall, we found no effect of a moderate dose of vitamin A supplementation on the duration of uncomplicated pneumonia in underweight or normal-weight children aged <5 y. However, a beneficial effect was seen in children with high basal serum retinol concentrations.  相似文献   
20.
The metabolism of serotonin was studied in cancer patients of their first day of their first course of chemotherapeutic drugs either with strongly or moderately emetogenic regimens. It was observed that strongly emetogenic treatments induce greater increases in serotonin release than moderately emetogenic regimens. High-dose cisplatinum (75 +/- 5 or 83.8 +/- 5 mg m-2) produced a marked increase in the plasma levels and in the urinary excretion of 5-hydroxyindole acetic acid (5-HIAA). Neither platelet nor plasma (platelet-free plasma) serotonin were significantly modified by high-dose cisplatinum. Dacarbazine (283 +/- 22 mg m-2), another strongly emetogenic agent, induced acute nausea and emesis paralleled by marked increases in the urinary excretion of 5-HIAA. Both for high-dose cisplatinum and dacarbazine, the increases in serotonin metabolism occurred with a similar time-course than those of vomiting, and lasted for a period of 4 to 8 h. Low-dose cisplatinum (30.8 +/- 3 mg m-2) as well as cyclophosphamide-based chemotherapies (520 +/- 30 mg m-2) produced very small increases in the urinary excretion of 5-HIAA. Platelet and plasma serotonin levels failed to increase in cyclophosphamide-treated patients. Octreotide, a long-acting somatostatin analog, did not inhibit the increase in urinary 5-HIAA and the nausea and vomiting produced by high-dose cisplatinum. These results suggest that for treatments that induce marked increases in serotonin release such as high-dose cisplatinum or dacarbazine: (a) the amount and time course of serotonin release induced by chemotherapeutic drugs determines the severity, time of onset and pattern of emesis observed; (b) platelet serotonin play no role in chemotherapy-induced emesis; (c) strongly emetogenic regimens release serotonin from enterochromaffin cells; and (d) intestinal release of serotonin is the consequence of the damage induced by the chemotherapeutic drugs on the gut mucosa.  相似文献   
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