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71.
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   
72.
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   
73.
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   
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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   
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The effects of inhibitors of 2,3-oxidosqualene:lanosterol cyclase (cyclase) on cytochrome P450 expression were investigated in primary cultures of rat hepatocytes. Treatment of hepatocyte cultures for 24 h with either of the inhibitors [4'-(6-allyl-methyl-amino-hexyloxy)-2'-fluoro-phenyl]-(4-bromophenyl)-methanone fumarate (Ro 48-8071) or trans-N-(4-chlorobenzoyl)-N-methyl-(4-dimethylaminomethylphenyl)-cyclohexylamine (BIBX 79) selectively increased CYP3A mRNA and immunoreactive protein contents, with maximal accumulations occurring at 3 x 10(-5) M Ro 48-8071 and 10(-4) M BIBX 79. The abilities of Ro 48-8071, BIBX 79, and 3beta-(2-diethylaminoethoxy)androst-5-en-17-one.HCl (U18666A) to induce murine CYP3A were abolished in hepatocyte cultures prepared from pregnane X receptor (PXR)-null mice, and cotransfection of primary cultured rat hepatocytes with a dominant-negative PXR prevented cyclase inhibitor-inducible luciferase expression from a PXR-responsive reporter plasmid. Cyclase inhibitor-mediated CYP3A mRNA induction was eliminated when primary cultured rat hepatocytes were cotreated with any of the following agents that inhibit steps upstream of cyclase in the cholesterol biosynthetic pathway: squalestatin 1 (squalene synthase inhibitor), (E)N-ethyl-N-(6,6-dimethyl-2-hepten-4-ynyl)-3-[(3,3'-bithiophen-5-yl)methoxy]benzenemethanamine (NB-598, squalene monooxygenase inhibitor), or pravastatin (HMG-CoA reductase inhibitor). Ro 48-8071-inducible CYP3A mRNA expression was restored when pravastatin-treated cultures were incubated with medium containing mevalonate. The concentration-dependence of Ro 48-8071-mediated CYP3A mRNA induction corresponded to the cellular contents of metabolically labeled squalene 2,3-oxide and squalene 2,3:22,23-dioxide, but not 24(S),25-epoxycholesterol. These results indicate that cyclase inhibitors are capable of inducing CYP3A expression in primary cultured rat and mouse hepatocytes and that the effect is mediated as a consequence of cyclase blockade through the evoked accumulation of one or more squalene metabolites that activate the PXR.  相似文献   
79.
Tuberculous granuloma of the spheno-clival region   总被引:1,自引:0,他引:1  
Shenoy SN  Raja A 《Neurology India》2004,52(1):129-130
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