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131.
132.
Cardiac herniation with volvulus is a catastrophic complication of right intrapericardial pneumonectomy. This case illustrates diagnostic radiographic findings that may be essential for early diagnosis and survival, since the clinical signs are nonspecific. 相似文献
133.
Exogenous opioid regulation of the hypothalamic-pituitary-adrenal axis in fetal sheep 总被引:1,自引:0,他引:1
To test the hypothesis that endogenous opioids participate in the regulation of the ontogenic development of the hypothalamic-pituitary-adrenal axis in fetal sheep, we measured changes in immunoreactive (ir) ACTH and cortisol concentrations in response to bolus injections of either the [Met]-enkephalin analogue, [D-Ala2,N-Phe4,Met(0)ol5]-enkephalin (FK 33-824; 25 micrograms), the opioid antagonist naloxone (1 mg), a combination of both, or saline vehicle, administered to chronically catheterized fetal sheep through late gestation. There were no effects of either FK 33-824, naloxone or saline on the release of ir-ACTH and cortisol at the earliest stage of gestation studied (days 110-115). By days 125-130, FK 33-824 caused a rapid but short-lived (30 min) increase in plasma ir-ACTH (P less than 0.05) which was accompanied by a smaller but nonsignificant increase in cortisol. Naloxone given concurrently with FK 33-824 abolished this response, thus providing evidence for a specific effect through opioid receptors. Naloxone given alone was without effect. At days 135-140, FK 33-824 caused a significant increase in ir-ACTH which was of similar duration and magnitude to that which occurred at days 125-130. There was a larger basal variation in plasma concentrations of cortisol than at days, 125-130, and a greater increase in cortisol after FK 33-824, although this did not reach statistical significance. Naloxone again reversed the effects of FK 33-824 but was without effect when given alone.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
134.
Sincetheintroductionofthefirstlineofangiotensinconvertingenzyme(ACE)inhibitors,ofwhichcaptoprilistheprototype,morepotentlonger-lastingagentshavebecomeavailable[l].AmongtheseisramipriIat,anonsL1lfhydrylACEinhibitorsimilarchemicallytoenalaprilatbutcontaininginadditionapentanering.Benderetal[2Jdemonstratedinvitrothatramiprilatisatleast23timesmorelipophilicthanenalaprilatwithanaffinityforACE47timesgreatc'rthanthatofcaptopril.ItwaspostulatedthatthemorelipophiIicanACEinhibitor,thebetteraccessi… 相似文献
135.
Congenital chylothorax in siblings 总被引:1,自引:0,他引:1
GF Fox D Challis KK O'Brien EN Kelly G Ryan 《Acta paediatrica (Oslo, Norway : 1992)》1998,87(9):1010-1012
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
136.
137.
A comparative fine structural investigation was carried out on the long-term effects on rat liver of chronic exposure to the carcinogen, N-nitrosopiperidine (NPIP) and its non-carcinogenic derivative, 2,2',6,6'-tetramethyl-N-nitrosopiperidine. Some morphological alterations apparently related to drug metabolism and toxicity were common to both compounds. Others, notably that involving the rough ER, were specific to NPIP and resembled those that are induced by other hepatocarcinogens and are characteristic of hepatic cell tumour. It is suggested that the rough ER lesion is associated with initiation and provides a morphological "marker" for the induction of liver neoplasia. 相似文献
138.
A new type of delta beta-thalassemia characterized by decreased expression of the beta-globin gene and increased expression of both G gamma and A gamma globin gene in the absence of a detectable deletion has recently been described in the Chinese population. In this study we characterize the mutant beta-globin gene from this delta beta- thalassemia chromosome. An A to G transversion is identified in the "ATA" sequence of the promoter region that leads to decreased expression of the beta-globin gene in vivo and in vitro. We also demonstrate the presence of this mutation in every individual with a high fetal hemoglobin phenotype in this family and its absence in every individual with a normal hemoglobin phenotype. This same promoter mutation has recently been detected in Chinese beta-thalassemia genes where it is present on chromosomes of the same haplotype as that of the delta beta-thalassemia chromosome we are studying. These data support the hypothesis that an as yet unidentified mutation occurred on the ancestral chromosome carrying the promoter mutation and subsequently gave rise to the delta beta-thalassemia phenotype. 相似文献
139.
Woo Syong Tan Robert Guaran Daniel Challis 《Journal of paediatrics and child health》2012,48(11):955-962
Maternal fetal medicine (MFM) is a subspecialty of obstetrics that focuses on identified risk pregnancies. The role includes obstetric ultrasound for fetal assessment and diagnosis of anomalies, invasive prenatal diagnosis and management of pregnancies complicated by maternal medical disorders, multiple fetuses and the antenatal management of extreme prematurity. Skill specialisation within MFM includes fetal interventions such as fetal shunting procedures, intrauterine transfusion, fetoscopic laser photocoagulation of anastomotic vessels for twin to twin transfusion syndrome and ex utero intrapartum treatment. MFM specialists are actively involved in clinical and basic science research to improve maternal and neonatal outcomes. Most Australian MFM specialists are associated with metropolitan teaching hospitals. MFM sub‐specialisation has reduced the impact of disability associated with aneuploidy, structural anomalies, multiple pregnancy and extreme prematurity. Management aims are to give families timely counselling, appropriate intervention, and optimisation of the time and location of delivery. The aim of this paper is to update the reader regarding current advances in MFM practices. 相似文献
140.