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101.
Objectives

To find out the relative prevalence of fetal neural tube defect (NTD) and its outcome in terms of survival at birth and beyond 2 years of age.

Methods

A 10-year prospective (2008–2018) observational study was performed, which included all prenatally detected fetal NTD. Two-year follow-up was done in cases of pregnancies resulting in live birth, in terms of their survival, physical morbidity and developmental delay.

Results

NTD was seen in 401/648 (62%) cases among the central nervous system malformations. More than half of the cases (54.1%) presented after 20 weeks of gestation, and 42.8% of the mothers were primiparous. Spina bifida was seen in 206 cases, anencephaly in 144, encephalocele in 43, whereas iniencephaly was seen in only eight cases. Associated anomalies were present in 51.2%. Only 19.0% cases were live-born, and merely 11% were alive beyond 2 years of age. Among types of spina bifida, lumbosacral meningomyocele was the most common (41.6%), whereas thoracic was the rarest (8.7%). After 2 years, physical disability was observed in more than half of the cases who survived.

Conclusions

NTD is one of the commonest malformations with high mortality, and the physical and mental sub-normality is high among those who survive.

  相似文献   
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PD-L2 is a second ligand for PD-1 and inhibits T cell activation   总被引:1,自引:0,他引:1  
Programmed death I (PD-I)-deficient mice develop a variety of autoimmune-like diseases, which suggests that this immunoinhibitory receptor plays an important role in tolerance. We identify here PD-1 ligand 2 (PD-L2) as a second ligand for PD-1 and compare the function and expression of PD-L1 and PD-L2. Engagement of PD-1 by PD-L2 dramatically inhibits T cell receptor (TCR)-mediated proliferation and cytokine production by CD4+ T cells. At low antigen concentrations, PD-L2-PD-1 interactions inhibit strong B7-CD28 signals. In contrast, at high antigen concentrations, PD-L2-PD-1 interactions reduce cytokine production but do not inhibit T cell proliferation. PD-L-PD-1 interactions lead to cell cycle arrest in G0/G1 but do not increase cell death. In addition, ligation of PD-1 + TCR leads to rapid phosphorylation of SHP-2, as compared to TCR ligation alone. PD-L expression was up-regulated on antigen-presenting cells by interferon gamma treatment and was also present on some normal tissues and tumor cell lines. Taken together, these studies show overlapping functions of PD-L1 and PD-L2 and indicate a key role for the PD-L-PD-1 pathway in regulatingT cell responses.  相似文献   
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BACKGROUND: Percutaneous transhepatic cholangiography (PTC) has been the preferred investigation to delineate the anatomy of the biliary tract in a patient with a bile duct stricture after cholecystectomy. Recently magnetic resonance cholangiography (MRC) has been described to evaluate the obstructed biliary tract. This paper reports a comparison of MRC with PTC in evaluating patients with an iatrogenic bile duct stricture. METHODS: This was a prospective study of 26 patients who had surgery for a bile duct stricture after cholecystectomy. Before operation all patients underwent both MRC and PTC, the results of which were compared with the intraoperative findings. RESULTS: Both PTC and MRC were comparable with regard to image quality, detection of intrahepatic bile duct dilatation, assessment of the level of injury and detection of abnormalities such as intraduct calculi, cholangitic liver abscesses and atrophy of liver lobes. MRC provided additional information in four patients, including detection of associated fluid collections (n = 3) and portal hypertension (n = 1). In eight patients more than one puncture had to be performed during PTC to delineate the complete anatomy. CONCLUSION: MRC is an accurate and non-invasive imaging procedure for preoperative evaluation of patients with a bile duct injury after cholecystectomy, and is capable of providing additional information which may not be available with PTC.  相似文献   
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The development of multidrug resistance (MDR) causes problems in the chemotherapy of human cancer. The present study was designed to evaluate and establish the role of Eclipta alba as MDR reversal agent using multidrug resistant hepatocellular carcinoma cell line (DR-HepG2). To develop DR-HepG2, hepatocellular carcinoma cell line (HepG2) was transfected with 2-Acetylaminofluorene (AAF) and Aflatoxin B1 (AFB). Cytotoxic effects of the Eclipta alba hydroalcoholic extract (EAE) and standard anti-ancer drug Doxorubicin (DOX) were determined in DR-HepG2 and the parental cells HepG2 using MTT assay. The expression level of MDR1 gene and P-glycoprotein (P-gp) level was analyzed by RT-PCR and western blotting. From the present investigation, it was found that EAE (10 and 20 μg/ml) could significantly inhibit cell proliferation in DR-HepG2 whereas DOX (0.5 μg/ml) could not because of enhancement effect of MDR1/P-gp. This study demonstrated for the first time the antiproliferative activities of EAE in multidrug resistant DR-HepG2 cells. The findings revealed that Eclipta alba components are effective inhibitors of MDR1/P-gp.  相似文献   
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