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51.
Daily patterns of melatonin and 5-methoxytryptophol (5-ML) concentrations and of aryl alkylamine N-acetyltransferase (AA-NAT) and hydroxyindole-O-methyltransferase (HIOMT) activities have been measured in the cerebroid ganglions, visceral ganglions, and ocular tentacles of the gastropod mollusc Helix aspersa maxima. Melatonin concentrations are very low in all the studied structures, except a small peak at the end of the night in the cerebroid ganglions. 5-ML, which is quite undetectable in the cerebroid and visceral ganglions, shows clear daily variations in the ocular tentacles with low values in the middle of the light period and high values during the night. These results are opposite to what is known on daily variations of 5-ML in vertebrates. AA-NAT activity was not detected, while the presence of an HIOMT-like activity supports the hypothesis that 5-ML is synthesized in the ocular tentacles. The temporal relationships existing between the 5-ML rhythm in the ocular tentacles and the hemolymph suggest that 5-ML could be released in the general circulation. These preliminary results suggest that 5-ML could be an informative molecule involved in adaptative processes in the snail and they reinforce the hypothesis that the different 5-methoxyindoles could be implicated in the integration of environmental information.  相似文献   
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Summary A 54-year-old female presented with a three-year history of proximal muscle weakness and arthralgia. EMG, muscle enzymes and biopsy and other tests were consistent with idiopathic polymyositis. At a later stage, she developed plaques of morphoea involving the dorsum of hands and forearms. There was no evidence of systemic sclerosis throughout the course of the disease. In our opinion, such association appeared as an unusual overlap syndrome that provided a new constellation of features in connective tissue disease.  相似文献   
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Attia J  Page J 《ACP journal club》2001,134(3):A11-A12
Students of evidence-based medicine often try unsuccessfully to commit to memory a particular critical appraisal framework (often lengthy), or they have to depend on pocket cards and are lost without them. We have described a pedagogic aid: a flow diagram of an RCT, which has been developed over years of teaching residents. This diagram focuses on the steps in an RCT, and by drawing arrows, it highlights the biases possible at each step. This diagram serves as a framework on which the list of critical appraisal questions can be hung and is easy to remember.  相似文献   
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Anorexia nervosa (AN) is a devastating psychiatric disorder characterized by extreme restriction of food intake and low body weight, both associated with significant medical and psychological morbidity. The clinical severity of AN has prompted the consideration and study of behavioral and pharmacological treatments in efforts to establish empirically based methods to reduce the burden of the disorder. Among adolescents, family-based treatment is considered a first-line behavioral treatment. Research continues to explore the efficacy of family-based treatment and predictors of treatment response to further improve outcomes. Several behavioral treatments for adults also exist, including cognitive-behavioral therapy, exposure and response prevention, third-wave acceptance-based treatments, and supportive psychotherapy, all of which help to improve symptoms and promote modest weight gain. Despite this, no one treatment is considered superior, and all existing behavioral approaches leave a proportion of adults symptomatic or at a high risk of relapse. As such, among adults, there is continued need for development of novel, mechanism-based approaches to better target the core symptoms of AN. Although antidepressants impart little benefit on weight or symptoms, the second-generation antipsychotic olanzapine has shown ability to promote modest weight gain in outpatients with AN. Most recently, the field's evolving conceptualization of AN as a biologically based disorder coupled with technological advancements has led to consideration of varying neuromodulation strategies as a potential therapeutic approach that remains under investigation.  相似文献   
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A central venous catheter is the most common access for initiating hemodialysis. Prolonged access through a central venous catheter increases the risk of infection and dysfunction of the catheter with potential development of catheter-induced thrombosis and embolism. However, fracture and dislodgement of the catheter with subsequent embolization is an unexpected complication. Endovascular treatment is a promising method to remove intravascular foreign bodies. We herein report a case of a 58-year-old woman undergoing prolonged hemodialysis who required central venous catheter removal because of mechanical fracture of the tunneled cuffed catheter and its migration in the internal jugular vein. An urgent chest X-ray showed that the two free ends of the fractured tunneled cuffed catheter were located in the right atrium and right internal jugular vein. Phlebotomy of the internal jugular vein was successfully performed to retrieve the fractured tunneled cuffed catheter and the associated thrombi. In this case, phlebotomy for retrieval of the embolized catheter fragment extending into the right atrium was a safe alternative to an endovascular technique of catheter fragment retrieval. Phlebotomy preserved the integrity of the catheter fragment and its associated thrombus and was both cost-effective and safe.  相似文献   
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