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71.
Although gastric hypochlorhydria is a risk factor for gastroenteritis and for gastric cancer, no reliable, inexpensive, noninvasive
test exists for screening or epidemiologic studies. We aimed to evaluate the sensitivity and specificity of the blood quininium
resin test (bQRT) for hypochlorhydria, against pH monitoring. Twelve fasting adult volunteers—seven with and five without
H. pylori infection—ingested 80 mg/kg of quininium resin twice, once with and once without acid suppression. Gastric pH was monitored
for 75 minutes; serum samples were obtained at times 0 and 75 minutes. The bQRT levels were compared to gastric pH, controlling
for omeprazole use and H. pylori infection. Subjects with a median recorded pH ≥3.5 were considered hypochlorhydric. Using a bQRT level of 10 as a cutoff
for hypochlorhydria, the sensitivity and specificity of the bQRT were 100% and 37.5%, respectively. The bQRT predicted omeprazole
use more accurately than pH monitoring. In conclusions, The bQRT has a high sensitivity for hypochlorhydria, making it potentially
useful in populations with a high prevalence of hypochlorhydria. In its current formulation, the bQRT's low specificity makes
it less useful in low-risk population.
Supported in part by NIH grant 5 M01 RR000070 from the National Center for Research Resources, and in part by NIH grant RO1
DK53689. 相似文献
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M. El‐Alfy C. Deloche L. Azzi B.A. Bernard F. Bernerd J. Coutet V. Chaussade C. Martel J. Leclaire F. Labrie 《The British journal of dermatology》2010,163(5):968-976
Background Although low dehydroepiandrosterone (DHEA) is suspected to have a role in skin ageing, little information is available on the mechanisms potentially involved. Objectives To obtain information on androgen receptor (AR) and procollagen expression in ageing skin during DHEA treatment. Methods A placebo‐controlled, randomized, prospective study was performed with 75 postmenopausal women aged 60–65 years. The women were treated twice daily for 13 weeks with 3·0 mL of placebo or 0·1%, 0·3%, 1% or 2% DHEA cream applied on the face, arms, back of hands, upper chest and right thigh where 2‐mm biopsies were collected before and after treatment. Results Although the overall structure of the epidermis was not significantly affected at the light microscopy level, AR expression examined by immunocytochemistry was markedly increased by DHEA treatment. In the dermis, the expression levels of procollagen 1 and 3 mRNA estimated by in situ hybridization were increased by DHEA treatment. In addition, the expression of heat shock protein (HSP) 47, a molecule believed to have chaperone‐like functions potentially affecting procollagen biosynthesis, was also found by immunocytochemistry evaluation to be increased, especially at the two highest DHEA doses. Conclusion These data suggest the possibility that topical DHEA could be used as an efficient and physiological antiageing skin agent. 相似文献
75.
Adapalene 0.1%/benzoyl peroxide 2.5% gel reduces the risk of atrophic scar formation in moderate inflammatory acne: a split‐face randomized controlled trial
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PC Ng J Hiu TF Fok EAS Nelson KL Cheung W Wong 《Acta paediatrica (Oslo, Norway : 1992)》1995,84(8):955-956
We report an unusual case of localized congenital tuberculosis otitis in a preterm infant. Unlike disseminated congenital cases, the manifestations of localized otitis are associated with a triad of signs: (i) regional lymphadenopathy in the absence of typical systemic features of tuberculosis; (ii) delayed onset of presentation; and (iii) refractory otitis unresponsive to conventional antimicrobial agents. The need for greater diligence in looking for neonatal tuberculosis is emphasized, especially in an ethnic or socioeconomic environment where the disease is prevalent. Congenital tuberculosis, otitis, preterm
PC Ng, Department of Paediatrics, Level 6, Clinical Sciences Building, Prince of Wales Hospital, Shatin, NT, Hong Kong 相似文献
PC Ng, Department of Paediatrics, Level 6, Clinical Sciences Building, Prince of Wales Hospital, Shatin, NT, Hong Kong 相似文献
80.
The correlates of long-term protection from measles infection are poorly understood. We followed the development of measles-specific antibody and lymphoproliferative (LP) responses in 60 children for 6 months after MMR vaccination. Prevaccine plaque reduction neutralization antibody (PRN Ab) values were low (mean+/-SEM 9.9+/-1. 1). Ninety-three percent (56/60) had excellent PRN values at 6 months (PRN 1816+/-207). Prevaccine LP activity was also low (stimulation index (SI)=1.4+/-0.1) but increased rapidly (SI 10. 7+/-4.5 at 2-3 weeks; p<0.05). However, only 61% (37/60) of the children had both significant cellular and antibody responses (SI>/=3 and PRN>/=120: Ab(hi)CMI(hi)). One child had a strong LP response (SI=6.7) despite little antibody production (PRN=19 at 6 months: Ab(lo)CMI(hi)). We also conducted a cross-sectional study in a separate group of 87 children 5-13 years after MMR vaccination. PRN values >/=120 were present in most children at 5-8 (n=28) and 9-13 years (n=59) after vaccination (PRN 550+/-120 and 360+/-60, respectively) but a significant minority had either undetected or 'subprotective' values (29 and 34%, respectively). LP responses (SI>/=3) were detectable in 19/28 (66%) and 36/59 (56%) of the children 5-8 and 9-13 years after vaccination (SI 11.4+/-2.4 and 7. 75+/-1.9, respectively). Almost two thirds (18/28) of the children in the cross-sectional study with low or absent antibody titers (PRN 41+/-6) had strong LP responses to measles antigens (SI 6.8+/-1.3). These data suggest that LP responses may be better sustained than antibody titers in some children. The susceptibility of Ab(lo)CMI(hi) children to infection and the value of the early LP response for predicting the durability of immunity remain to be determined. 相似文献