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Background

Adequate vitamin D concentrations during pregnancy are necessary to neonatal calcium homeostasis, bone maturation and mineralization. The aim of study is to evaluate serum vitamin D concentrations in mothers and their newborns and effect of vitamin D deficiency on pregnancy outcomes.

Methods

552 pregnant women were recruited from Tehran University educating hospitals in the winter of 2002. Maternal and cord blood samples were taken at delivery. The serum was assayed for 25-hydroxyvitamin D3, calcium, phosphorus and parathyroid hormone.

Results

The prevalence of vitamin D deficiency in maternal and cord blood samples were 66.8% and 93.3%, respectively (<35 nmol/l). There was significant correlation between maternal and cord blood serum concentrations of vitamin D. In mothers with vitamin D deficiency, cord blood vitamin D concentrations was lower than those from normal mothers (P = .001). Also, a significant direct correlation was seen between maternal vitamin D intake and weight gain during pregnancy.

Conclusion

Consideration to adequate calcium and vitamin D intake during pregnancy is essential. Furthermore, we think it is necessary to reconsider the recommendation for vitamin D supplementation for women during pregnancy.  相似文献   
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Multiple factors can influence bioavailability, which can make predictions of toxicity in natural systems difficult. The current study examined the potential use of solid-phase microextraction fibers as a matrix-independent approach to predict the toxicity of permethrin to Daphnia magna across various water sources, including a laboratory reconstituted water, two natural waters, and a modified natural water. Water source strongly affected the toxicity of permethrin as well as the concentration–response relationships. Although permethrin concentrations in the water were predictive of toxicity to D. magna for individual water sources, there was no relationship between permethrin concentrations among water sources and mortality. This indicated that compositional differences among water sources can greatly influence toxicity, suggesting that benchmarks established using reconstituted water may be overly conservative for some natural waters. In addition, although permethrin tissue residues were predictive of mortality for individual waters, the correlation among waters was not as clear. Finally, both 48-h and equilibrium-based SPME fiber concentrations adequately predicted toxicity independent of water properties. This demonstrated that bioavailability-based estimates provided a more accurate prediction of toxicity than water concentrations and that SPME fibers could be used in environmental monitoring as a rapid and accurate means of predicting toxicity in natural waters.  相似文献   
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BACKGROUND: Pantoprazole is a substituted benzimidazole which is a potent inhibitor of gastric acid secretion by its action upon H+, K+- ATPase. METHODS: Pantoprazole 40 mg and 80 mg were compared in a randomized double-blind study in 192 out-patients with stage II or III (Savary-Miller classification) reflux oesophagitis. Patients received either pantoprazole 40 mg (n = 97) or pantoprazole 80 mg (n = 95), once daily before breakfast for 4 weeks. Treatment was extended for a further 4 weeks if the oesophagitis had not healed. RESULTS: After 4 weeks complete healing of the reflux oesophagitis was seen in 78% of protocol-correct patients given pantoprazole 40 mg daily (n = 86), and in 72% in the 80 mg (n = 87) group. The cumulative healing rates after 8 weeks were 95 and 94%, respectively (P > 0.05, Cochran-Mantel- Haenszel), and time until healing of oesophagitis comparable in both groups. Differences between doses were also not significant in an intention-to-treat analysis. Both dosing schedules were well tolerated and the patients experienced remarkable symptom relief. No adverse event or changes in laboratory values of clinical significance could definitely be ascribed to the trial medication. CONCLUSION: The 40 mg pantoprazole dosage is comparable to 80 mg in reflux oesophagitis, both in efficacy and tolerability.  相似文献   
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The goal of this study was to examine whether supplemental fructooligosaccharides (FOS) and (or) mannanoligosaccharides (MOS) influenced indices of gut health of dogs. Adult female dogs (n = 4) surgically fitted with ileal cannulas were fed a dry, extruded, kibble diet twice daily. At each feeding, the following treatments were administered: 1) Control (no FOS or MOS); 2) 1 g FOS; 3) 1 g MOS; or 4) 1 g FOS + 1 g MOS. Fecal, ileal and blood samples were collected during the last 4 d of each 14-d period to measure protein catabolite concentrations, microbial populations, immune characteristics and nutrient digestibilities. Treatment means were compared using preplanned orthogonal contrasts. Dogs supplemented with MOS had lower (P = 0.05) fecal total aerobes and tended to have greater (P = 0.13) Lactobacillus populations. Ileal immunoglobulin (Ig) A concentrations were greater (P = 0.05) in dogs supplemented with FOS + MOS vs. control. Lymphocytes (% of total white blood cells) were greater (P < 0.05) in dogs supplemented with MOS. Serum IgA concentrations also tended (P = 0.13) to be greater in dogs supplemented with MOS. Dogs supplemented with FOS and FOS + MOS had lower (P < 0.05) fecal total indole and phenol concentrations. Dogs supplemented with MOS tended to have lower ileal DM (P = 0.149) and OM (P = 0.146) digestibilities vs. control. Results of this study suggest that dietary supplementation of FOS and MOS may have beneficial effects on colonic health and immune status of dogs.  相似文献   
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Radiotherapy and multimodality management of cholangiocarcinoma   总被引:2,自引:0,他引:2  
PURPOSE: To evaluate the results of radiotherapy in cholangiocarcinoma patients managed with various combinations of chemotherapy and surgical resection with selective liver transplantation. METHODS AND MATERIALS: From January 1990 to December 1995, 61 patients with histologically confirmed biliary duct adenocarcinoma were seen in the Radiation Oncology Department of the University of Pittsburgh. Median follow-up was 22 months (1 to 91 months). The extent of surgery was complete resection in 23 patients (including 17 with orthotopic liver transplant), partial resection in 4, and biopsy in 34. All patients had radiotherapy; median dose was 49.5 Gy. Thirty patients received chemotherapy: 5-fluorouracil (5-FU)-leucovorin with interferon alpha (IFNalpha) in 27, and taxol in 3. RESULTS: The median survival was 20 months (95% CI 15-25 months). The 5-year actuarial survival was 23.8 +/- 6.8%. The only significant variable in multivariate analysis was achieving a complete resection with negative margins through conventional surgery or liver transplantation (p = 0.001, hazard rate ratio [HRR] = 0.25, 95% CI 0.12-0.54). Patients with complete resections had a 5-year actuarial survival of 53.5 +/- 10.9%. CONCLUSION: Combined modality therapy that includes complete surgical resection with or without transplantation can be curative in the majority of patients with biliary duct carcinoma. Further study is needed to better define the roles of chemotherapy and radiotherapy in cholangiocarcinoma.  相似文献   
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