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71.
Intrahepatic cholestasis of pregnancy (ICP) is a pregnancy specific liver disease associated with significant risk of fetal complications. It is hypothesised that the risk of adverse fetal outcomes relates to the toxic effects of bile acids, the levels of which are increased in both maternal and fetal serum. Human and rodent studies have shown that transplacental transfer of bile acids is impaired in ICP. Furthermore, the morphology of placentas from the rodent model of ICP is markedly abnormal, and is associated with increased expression of apoptotic markers and oxidative stress. Using placental tissue from ICP cases and normal pregnancies and cultured placental explant fragments we investigated the histological and molecular effects of cholestasis. We also examined the influence of ursodeoxycholic acid (UDCA) administration on these parameters. Here we report that ICP is associated with several morphological abnormalities of the placenta, including an increase in the number of syncytial knots, and that these can be reproduced in an in vitro (explant) model exposed to the bile acids taurocholic acid and taurochenodoexycholic acid. Furthermore, we demonstrate that ursodeoxycholic acid, a drug commonly used in the management of ICP, has a protective effect on placental tissue both in vivo and in vitro.  相似文献   
72.
McGahan  JP; Lindfors  KK 《Radiology》1989,173(2):481-485
Emergency percutaneous cholecystostomy was successfully performed in 39 of 40 attempted procedures in 37 hospitalized patients with possible acute cholecystitis. All cholecystostomies were performed with ultrasound guidance and preferentially with the transhepatic route, and all but four were performed at the patient's bedside. The patients had been hospitalized an average of 27 days before the procedure. Twenty-two of the 37 patients (59%) eventually died during hospitalization because of other medical or surgical problems. Only minor complications related to percutaneous cholecystostomy placement occurred in this series: catheter dislodgment without sequelae (n = 2) and significant abdominal pain (n = 2). Technical problems included guide-wire buckling during catheter insertion (n = 1) and failed attempted cholecystostomy (n = 1). Percutaneous cholecystostomy is a safe alternative to surgical cholecystostomy in the treatment of patients suspected of having acute cholecystitis.  相似文献   
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Full-frame transform compression of CT and MR images   总被引:3,自引:0,他引:3  
Chan  KK; Lou  SL; Huang  HK 《Radiology》1989,171(3):847
  相似文献   
76.
With only a few exceptions, the precursor cells representing the normal counterparts of human tumours are unknown. The comparative lack of information about the lineages involved in tissue development, and difficulties in growing many human tumors in a manner suitable for cellular biological analysis, together often make it difficult to study the differences between normal and tumor and tumor cells and to develop many of the model systems that would be useful in the study of human cancer. By applying techniques previously utilized to study glial progenitor cells, we have isolated a human glioblastoma multiforme (GBM)-derived population that expresses many properties otherwise uniquely expressed by oligodendrocyte-type-2 astrocyte (O-2A) progenitor cells. Hu-O-2A/Gb1 (for Human O-2A lineage Glioblastoma number 1) cells responded to similar mitogens and differentiation modulators as rodent O-2A progenitors, and generated cells with features of precursor cells, oligodendrocytes and astrocytes. Moreover, 1H-NMR analysis of amino acid composition demonstrated a striking conservation of types and quantities of free amino acids between the human tumour cells and the rodent primary cells. Hu-O-2A/Gb1 cells represent the first human glioma-derived population for which unambiguous lineage assignment has been possible, and our results indicate that the human O-2A lineage can contribute to one of the most malignant of glial tumours. In addition, the highly diagnostic 1H-NMR spectrum expressed by Hu-O-2A/Gb1 cells raises the possibility of eventual non-invasive identification of tumors of this lineage. © 1995 Wiley-Liss, Inc.  相似文献   
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An infant with features of fetal hydantoin syndrome, born to an epileptic mother, was followed from birth to 20 months of age. Physical findings included gum hypertrophy, digitalization of the thumbs, hypoplasia of the distal phalanges and nails, epicanthal folds, pseudohypertelorism, epidermoid cyst, and geographic tongue. Available literature about the disorder is reviewed.  相似文献   
79.
Congenital chylothorax in siblings   总被引:1,自引:0,他引:1  
We describe two cases of congenital chylothorax in siblings with important differences from previously described familial cases. Our findings support the likelihood of an autosomal recessive inheritance in some cases of this condition, rather than X-linked recessive inheritance, which has also been suggested. Autopsy findings from one of these cases and others previously described suggest that the pathophysiological mechanisms involved may be variable.  相似文献   
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