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41.
R V Farese  M A Sabir  R E Larson 《Endocrinology》1981,109(6):1895-1901
We tested further our postulate that enhanced de novo synthesis of phosphatidic acid is responsible for ACTH- and cAMP-induced increases in adrenal phospholipids in the phosphatidate polyphosphoinositide pathway. During incubation of adrenal sections or cells in vitro, ACTH and cAMP increased the concentrations of and incorporation of [3H]glycerol and [14C]palmitate into phosphatidylcholine and phosphatidylethanolamine, two major phospholipids which are derived from phosphatidic acid, but are extrinsic to the inositide pathway. Thus, it is unlikely that ACTH and cAMP increase inositide phospholipids at the expense of other phospholipids. Similar to previously reported effects on phosphatidic acid and inositide phospholipids, cycloheximide blocked the effects of ACTH and cAMP on phosphatidylcholine and phosphatidylethanolamine. In addition, Ca++ was required for these effects, as well as for cAMP-induced increases in phosphatidic acid, inositide phospholipids, and steroidogenesis. Our findings strongly suggest that ACTH, via cAMP, stimulates de novo phosphatidate synthesis by a cycloheximide-sensitive, Ca++-dependent process, and this stimulation causes a rapid generalized increase in adrenal phospholipids. Moreover, the increased incorporation of labeled glycerol and palmitate into phospholipids suggests that ACTH and cAMP may stimulate the glycerol-3'-PO4 acyltransferase reaction. This stimulatory effect may play a central role in the steroidogenic and trophic actions of ACTH and cAMP.  相似文献   
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True intramedullary spinal cord lipomas are extremely rare. Two cases of intramedullary spinal cord lipoma are presented. The patients did not exhibit any form of spinal dysraphism. The patients presented with gait difficulty, upper limb weakness, sphincter disturbance, dysesthesias and neck pain. The tumors were removed sub-totally and the neurological grade improved postoperatively in one of the patients.  相似文献   
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The handover of patient information between shifts enables continuity of care and increases patient safety. We surveyed UK practice during handovers in obstetric anaesthesia. A questionnaire was sent to 239 lead consultant obstetric anaesthetists to record routine practice in their unit and individual opinion about handover procedures. Responses were received from 168 anaesthetists, a 70% response rate. Handover policies were available in 10% of units. Most (76%) responding units had an allocated time for handover. In most units (76%), the duration of handover was reported as being < 15 min but the actual duration and depth of any discussion involved were not specified. Handovers were rarely documented in writing (7%). Consultant anaesthetists were most likely to be present at the morning handover and few handovers were multidisciplinary. Four percent of units reported critical incidents following inadequate handovers in the past 12 months. We identify features in handover procedures that could be improved.  相似文献   
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We studied certain metabolic requirements for insulin-induced increases in phospholipids, and the relationship of phospholipid changes to the insulin-induced activation of pyruvate dehydrogenase, in rat adipocytes and fat pads in vitro. Increases in the contents of phosphatidylinositol and phosphatidylserine mass were maximal in rat fat pads within 10 min of incubation with insulin, and preceded or accompanied measurable increases in pyruvate dehydrogenase activity. In dose-response studies, the contents of these phospholipids and pyruvate dehydrogenase activity increased in parallel in response to increasing concentrations of insulin. Cycloheximide and puromycin inhibited insulin-induced increases in the mass of both of these phospholipids, as well as (in confirmation of previous reports) pyruvate dehydrogenase activity. Effects of insulin on phospholipid metabolism and pyruvate dehydrogenase were found to require an exogenous carbohydrate source, and fructose was nearly as effective as glucose in this regard. Insulin-induced increases in phosphatidylinositol and phosphatidylserine were demonstrated in the mitochondrial fraction, which is also the subcellular locus of pyruvate dehydrogenase. The present findings suggest that there is a relationship between insulin-induced increases in phospholipids and pyruvate dehydrogenase activity, but the nature of this relationship remains to be defined.  相似文献   
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BACKGROUND & OBJECTIVES: Recently there were reports from all over India about changing spectrum of clinical presentation of severe malaria. The present study was planned to study the same in the northwest India. METHODS: This prospective study was conducted on patients of severe malaria admitted in a classified malaria ward of a tertiary care hospital in Bikaner, Rajasthan (northwest India) during 1994 and 2001. It included adult patients of both sexes belonging to all age groups. The diagnosis of Plasmodium falciparum was confirmed by demonstrating asexual form of parasites in peripheral blood smear. All patients were treated with i.v./oral quinine. The specific complications were treated by standard WHO protocol. The data for individual complications for both the years were analysed by applying chi-square test. RESULTS: In a prospective study in 1994 the spectrum of complication was dominated by cerebral malaria (25.75%) followed by jaundice (11.47%), bleeding tendencies (9.59%), severe anaemia (5.83%), shock (5.26%), Acute respiratory distress syndrome-ARDS (3.01%), renal failure (2.07%) and hypoglycemia (2.07%) whereas in 2001 it was dominated by jaundice (58.85%) followed by severe anaemia (26.04%), bleeding tendencies (25.52%), shock (10.94%), cerebral malaria (10.94%), renal failure (6.25%), ARDS (2.08%) and hypoglycemia (1.56%). The sharp difference for presence of jaundice and severe anaemia in 2001 and cerebral malaria in 1994 was statistically significant. Similarly, the important cause of mortality in 2001 was multiple organ dysfunction syndrome (71.10%) with predominant presentation of jaundice and renal failure, whereas in 1994, it was cerebral malaria (77.96%). INTERPRETATION & CONCLUSION: The observation of changing spectrum of severe malaria in this study and a significant increase in presentation with jaundice as an important manifestation is highly essential for primary, secondary and tertiary level health care providers for proper diagnosis and management.  相似文献   
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Stroke is the second common cause of death and the primary cause of early invalidity worldwide. Different from other diseases is the time sensitivity related to stroke. In case of an ischemic event occluding a brain artery, 2 000 000 neurons die every minute. Stroke diagnosis and treatment should be initiated at the earliest time point possible, preferably at the site or during patient transport. Portable ultrasound has been used for prehospital diagnosis for applications other than stroke, and its acceptance as a valuable diagnostic tool “in the field” is growing. The intrahospital use of transcranial ultrasound for stroke diagnosis has been described extensively in the literature. Beyond its diagnostic use, first clinical trials as well as numerous preclinical work demonstrate that ultrasound can be used to accelerate clot lysis (sonothrombolysis) in presence as well as in absence of tissue plasminogen activator. Hence, the use of transcranial ultrasound for diagnosis and possibly treatment of stroke bares the potential to add to current stroke care paradigms significantly.  相似文献   
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