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91.
92.
Heikkinen T Shenoy M Goldblum RM Chonmaitree T 《Acta paediatrica (Oslo, Norway : 1992)》1999,88(2):150-153
Free secretory component (FSC) has been recommended as a reliable protein for correction of the unknown dilution in tracheal aspirate samples from preterm infants. To investigate whether FSC would also provide a valid standardization protein for samples of nasopharyngeal secretions, this study determined the intersubject variation and the alteration over time in the concentrations of FSC in nasal secretions from 35 children (median age 14 months) who participated in an antibiotic efficacy trial. Nasopharyngeal aspirates were obtained at enrolment and after 2-3 d. FSC in the specimens was quantified by a direct enzyme immunoassay. The concentrations of FSC in the nasal secretions ranged from 0.08 to 189.6 μg ml-1 (median 12.3 μg ml-1); the ratio of the highest to the lowest concentrations was 2370, the difference between the 90th and 10th percentile concentrations was 189-fold and the difference between the 75th and 25th percentile values was 26. FSC concentrations were significantly lower in children aged ≤12 months (median 2.2 μg ml-1) than in the older children (median 21.5 μg ml-1; p = 0.035). Between the first and the follow-up specimens, 65% of the children had ≥2-fold difference in the levels of FSC in the secretions. Because an optimal standardization protein should show minimal variation between individuals and over time, FSC may not be a suitable protein for correction of the unknown dilution of nasopharyngeal specimens from children with upper respiratory tract infection. 相似文献
93.
94.
Effect of proton pump inhibitors on the detection of Helicobacter pylori in gastric biopsies. 总被引:4,自引:0,他引:4
BACKGROUND: Proton pump inhibitors are known to decrease the activity of Helicobacter pylori organisms within the stomach and to shift their distribution proximally. This effect may reduce the sensitivity of histological examination and rapid urease testing for H. pylori on biopsies taken from recommended sites. It is of particular relevance if a proton pump inhibitor has been prescribed before the patient has undergone diagnostic endoscopy. METHODS: We studied patients referred to our open-access upper gastrointestinal endoscopy service who had either been on no medication (controls) or were already taking proton pump inhibitors. Biopsies taken from the gastric antrum and corpus were used for rapid urease testing and for histological examination. Sera, taken from patients who had no evidence of H. pylori in biopsies, were tested for IgG H. pylori antibodies as an alternative indicator of infection. RESULTS: H. pylori organisms were detected by histological examination in 27 of 40 controls (68%) and in 13 of 25 patients taking proton pump inhibitors (52%). Among patients with positive histology (organisms detected in either antral or corpus biopsies, or both), only the sensitivity of the antral urease test read at 1 h was significantly lower in patients taking proton pump inhibitors than in controls, with no significant difference in sensitivities of the antral urease test at 24 h, of the corpus urease test at 1 or 24 h, or of histology from the antrum or corpus. Of patients with negative histology, none of 13 controls compared with six of 12 patients taking proton pump inhibitors (50%) had positive serology (P = 0.005). Five (83%) of the six histology-negative, seropositive patients taking proton pump inhibitors had histological changes consistent with H. pylori gastritis even though no organisms were detected. CONCLUSIONS: Treatment with a proton pump inhibitor before endoscopy reduces the sensitivity of antral and corpus biopsies for H. pylori detection, both by urease testing and histological examination. If proton pump inhibitors already prescribed cannot be discontinued for an adequate period before endoscopy, patients should have biopsies taken from the corpus as well as from the antrum, and serum should be tested for H. pylori. 相似文献
95.
Haptoglobulin phenotyping was carried out in fifty controls and in thirty five leprosy patients. In controls the incidence Hp phenotypes 2-2, 2-1 and 2-1 (Mod) is 76%, 16% and 8% respectively. In leprosy patients, the incidence of phenotypes 2-2, 2-1, 1-1 and 0-0 is 77%, 11%, 3% and 9% respectively. The incidence of phenotype 2-2, 1-1 and 0-0 is more in leprosy patients than in controls and is significant (p less than 0.05). In none of the leprosy patients phenotype 2-1 (Mod) was recorded. 相似文献
96.
Urinary excretion in man, of the unchanged drug and metabolite amphetamine, has been investigated after the (+)- and (-)-isomers of methyl-, ethyl-, n-propyl- and n-butyl- amphetamine had been taken by mouth under acidic urinary pH. The total metabolism of (+)-methyl-, ethyl-, and n-propyl-amphetamine was greater than that of the corresponding (-)-isomers but there was no difference in the total metabolism of the (+)- and (-)-n-butylamphetamine. A direct correlation was obtained for the (+)-but not the (-)-isomers between the partition coefficient of the compounds in an n-heptane/aqueous system, their buccal absorption and the total metabolism. The (+)-isomers of methyl- and ethyl-amphetamine were N-dealkylated more than their (-)-enantiomorphs but (-)-n-propylamphetamine was N-dealkylated more than the (+)-isomer. 相似文献
97.
98.
99.
Five-year follow up of thymoglobulin versus ATGAM induction in adult renal transplantation 总被引:2,自引:0,他引:2
Hardinger KL Schnitzler MA Miller B Lowell JA Shenoy S Koch MJ Enkvetchakul D Ceriotti C Brennan DC 《Transplantation》2004,78(1):136-141
BACKGROUND: One-year results of a randomized, double-blinded trial of Thymoglobulin versus Atgam for induction therapy in renal transplantation revealed that Thymoglobulin was associated with higher event-free survival (94% vs. 63%), less acute rejection (4% vs. 25%), and better graft survival. This article compares the safety and efficacy of Thymoglobulin versus Atgam induction through 5 years. METHODS: Review and analysis of clinic records and electronic databases. RESULTS: At 5 years, event-free survival (73% vs. 33%, P<0.001), graft survival (77% vs. 55%, P=0.047), and freedom from rejection (92% vs. 66%, P=0.007) were higher with Thymoglobulin versus Atgam. No additional cytomegalovirus (CMV) disease occurred after the first year with Thymoglobulin or Atgam (13% vs. 33%, P=0.056). There were two cases of posttransplant lymphoproliferative disorder (PTLD) with the Atgam arm and none with Thymoglobulin. Thymoglobulin was associated with profound lymphopenia at 2 years after transplantation. CONCLUSIONS: Thymoglobulin was associated with higher event-free survival, graft survival, and freedom from rejection without increased PTLD or CMV disease at 5 years compared with Atgam. The prolonged and profound lymphopenia may contribute to the long-term results associated with Thymoglobulin. 相似文献
100.
Oxidative stress in term small for gestational age neonates born to undernourished mothers: a case control study 总被引:1,自引:0,他引:1