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1.
The hepatic circulation of patients with hilar carcinoma and icterus was studied by isotope technique. A marked alternation in blood flow was observed, that is that the ratio of the circulation of the hepatic artery and the portal vein became balanced. By elimination of the icterus, the hepatic circulation normalized. This allowed the conclusion that the change in blood flow must have rather been due to the mechanical icterus and the increased pressure of the bile duct than to the tumorous infiltration and therefore the earliest possible elimination of the icterus is urgently indicated.  相似文献   
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The aim of the present study was to evaluate the effect of long-term (12 months) administration of raloxifene hydrochloride (60 mg/day) on the steroid production of the adrenal cortex and on the hypothalamic-pituitary-adrenal axis in postmenopausal women. We performed a basal evaluation, a corticotropin releasing factor (CRF) (100 microg i.v. bolus) test and a dexamethasone (DXM) (0.25 mg) suppression-adrenocorticotropic hormone (ACTH) (10 microg i.v. bolus) stimulation test in 11 postmenopausal women, before and after 3, 6 and 12 months of raloxifene treatment. Raloxifene administration significantly modified circulating levels of adrenal steroids, decreasing cortisol (-24%), dehydroepiandrosterone (DHEA) (-36%), and its sulfate (DHEAS) (-41%), and androstenedione (-29%), and increasing circulating allopregnanolone (+39%) levels. Progesterone and 17OH-progesterone levels remained unmodified, while estradiol and estrone levels showed a significant decrease (-51% for estradiol and -61% for estrone). We also observed an increase in circulating ACTH (+58%) and beta-endorphin (+120%). No modifications in the hormonal responses to CRF were observed during the treatment. DXM significantly suppressed circulating steroids at any time with a lower suppression of cortisol from the third month and a higher suppression of DHEA at 12 months. ACTH administration was associated with a significantly blunted cortisol response from the sixth month and a significantly increased response of allopregnanolone from the third month. The present data exclude a raloxifene effect on pituitary sensitivity to CRF and demonstrate a reduced adrenal sensitivity to ACTH, sustained by the opposite changes in basal cortisol and Delta5 androgens, which were reduced, and in ACTH and beta-endorphin, which were increased, as well by the reduced response of cortisol to the direct ACTH stimulus. The reduction of circulating cortisol levels and cortisol response to the ACTH challenge suggests that raloxifene protects against the neurotoxic effects of endogenous glucocorticoids. Furthermore, the progressive increase in basal allopregnanolone and its increased response to ACTH indicate that chronic raloxifene administration exerts direct effects on the pattern of adrenal enzymes, leading to specific changes in the circulating levels of this anxiolytic progesterone metabolite. The important reduction in the circulating levels of estradiol and estrone under long-term raloxifene administration may represent a further mechanism by which this molecule may exert a protective effect against breast and endometrial malignancies.  相似文献   
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The natural killing of K 562 cells by whole blood from normal subjects was comparable with that shown by separated mononuclear cells. In order to establish the conditions for a reliable natural killer assay by using very small numbers of effector cells in whole blood, the isotope uptake of target cells was increased by a modified labelling method, which permitted the use of fewer target cells in the assay. The natural cytotoxicity of whole blood was augmented by interferon to the same extent as observed with separated mononuclear cells. The chemiluminescence of granulocytes in whole blood comparable with that of separated granulocytes. Taken together, these methods are considerably less tedious than the conventional methods, technique is also economical, and the results may reflect in vivo cytolytic processes much better.  相似文献   
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Detectable TNF levels in sera 33% of patients with sepsis following pancreatitis have been found. No correlation was observed between serum TNF concentration and the severity of illness. However, monocytes and granulocytes of septic patients exerted higher TNF-mediated cytotoxicity than leukocytes of normal blood donors. The in vitro TNF-producing capacity was also higher in the patients in the study group, and it decreased only before fatal outcoming of sepsis. Our results suggest that determination of the TNF-producing capacity of leukocytes might be more informative than measurement of the serum TNF level in the evaluation of the severity or prognosis of sepsis.  相似文献   
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Bone mineral content (BMC) and testosterone levels were evaluated and compared in 10 hypogonadal males and 10 normal, age-matched controls. In 6 of the subjects an investigation was also carried out into the effects of testosterone administration on lumbar BMC, calcitonin (CT) response to hypercalcaemia, osteocalcin (BGP) and the fasting urinary calcium/creatinine and hydroxyproline/creatinine ratios. Our results confirm that male hypogonadism is characterized by a low BMC and that testosterone administration is able to improve this parameter and to increase both basal BGP and CT response to hypercalcaemia. Testosterone therefore probably acts on bone tissue through both a direct action on osteoblast cells and an improvement in CT secretion.  相似文献   
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The combination of ceruletide-induced relaxation of the sphincter of Oddi plus flushing with saline has recently been proposed as a novel procedure for the treatment of residual common bile duct (CBD) stones. In this study we have administered intravenous ceruletide (2 ng kg-1 body weight min-1 for 1 h) plus intraductal saline (800-3000 ml, infused at a rate that kept biliary pressure below 30 cmH2O) to a group of 14 patients. The treatment induced the passage of residual stones in 11 subjects (79 per cent) with complete clearance in 7 (50 per cent). The majority of the cleared concretions (11/15) had a diameter less than 10 mm. No severe side-effects were recorded during the treatment. Four of the seven subjects who exhibited incomplete CBD clearance underwent a short cycle of mono-octanoin administration in order to reduce the size of residual radiolucent stones. This course of treatment was followed by another attempt with intravenous ceruletide and saline washout which gave a successful response in an additional three cases. These data indicate that the combination of ceruletide and flushing is a safe and inexpensive method for treatment of residual stones. The procedure is feasible for both radiolucent and radio-opaque stones and is mainly eligible for small concretions of diameter less than 10 mm. Larger (greater than 10 mm) radiolucent stones may be partially dissolved with mono-octanoin and then eliminated by the washout technique.  相似文献   
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