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71.
OBJECTIVE: To describe a case of dissection of the postero-inferior cerebellar artery (PICA) after cervical manipulation. Clinical Features: After cervical manipulation, a 42-year-old woman had a cerebellar syndrome related to an infarct in the area supplied by the PICA, confirmed by computed tomography of the brain. Cerebral angiography showed a normal appearance of the vertebral artery, a cervical extradural origin of PICA, and a dissection of the latter at the C1-C2 level. Intervention and Outcome: Anticoagulant treatment with heparin was implemented. A positive outcome was achieved after 3 weeks. CONCLUSION: Anatomical variations of the vertebral arteries and their branches are not infrequent and may constitute a predisposing factor to complications after neck manipulation.  相似文献   
72.
Some patients with severe insulin resistance develop pathological tissue growth reminiscent of acromegaly. Previous studies of such patients have suggested the presence of a selective postreceptor defect of insulin signaling, resulting in the impairment of metabolic but preservation of mitogenic signaling. As the activation of phosphoinositide 3-kinase (PI 3-kinase) is considered essential for insulin's metabolic signaling, we have examined insulin-stimulated PI 3-kinase activity in anti-insulin receptor substrate (IRS)-1 immunoprecipitates from cultured dermal fibroblasts obtained from pseudoacromegalic (PA) patients and controls. At a concentration of insulin (1 nM) similar to that seen in vivo in PA patients, the activation of IRS-1-associated PI 3-kinase was reduced markedly in fibroblasts from the PA patients (32+/-7% of the activity of normal controls, P < 0.01). Genetic and biochemical studies indicated that this impairment was not secondary to a defect in the structure, expression, or activation of the insulin receptor, IRS-1, or p85alpha. Insulin stimulation of mitogenesis in PA fibroblasts, as determined by thymidine incorporation, was indistinguishable from controls, as was mitogen-activated protein kinase phosphorylation, confirming the integrity of insulin's mitogenic signaling pathways in this condition. These findings support the existence of an intrinsic defect of postreceptor insulin signaling in the PA subtype of insulin resistance, which involves impairment of the activation of PI 3-kinase. The PA tissue growth seen in such patients is likely to result from severe in vivo hyperinsulinemia activating intact mitogenic signaling pathways emanating from the insulin receptor.  相似文献   
73.

Background

Intragastric balloons (IGBs) are a minimally invasive option for obesity treatment, acting as a space-occupying device and leading to weight loss through increased satiety. This device has been growing in popularity owing to its safety profile and good weight loss results. However, there are no published guidelines that standardize the technical aspects of the procedure.

Objectives

To create a practical guideline for intragastric balloon usage.

Setting

Private and Academic Settings, Brazil.

Methods

A consensus meeting was held in São Paulo, Brazil, in June 2016, bringing together 39 Brazilian endoscopists with extensive experience in IGBs from all regions of the country. Topics on patient selection, indications, contraindications, multidisciplinary follow-up, technique, and adverse events were discussed in the form of questions. After electronic voting, a consensus was defined when there was ≥70% agreement. Experts were also requested to provide data on their experience with IGBs.

Results

The selected experts discussed and reached a consensus on 76 questions, mainly concerning specific indications and contraindications for the procedure; technical details, such as patient preparation, minimum balloon-filling volume, techniques for implant and explant; patient follow-up and recommended medication for the adaptation period; and adverse event management. The overall Brazilian expert data encompassed 41,863 IGBs, with a mean percentage total weight loss of 18.4% ± 2.9%. The adverse event rate after the adaptation period was 2.5%, the most common being hyperinflation (.9%) and spontaneous deflation (.8%) of the device. The early removal rate due to intolerance was 2.2%.

Conclusions

The present consensus represents practical recommendations for performing IGB procedures and reflects Brazil’s significant experience with this device. The experience of over 40,000 cases shows that the device leads to satisfactory weight loss with a low rate of adverse events.  相似文献   
74.
The major potential adverse effect of use of sulfonylurea agents (SUAs) is a hyperinsulinaemic state that causes hypoglycaemia. It may be observed during chronic therapeutic dosing, even with very low doses of a SUA, and especially in older patients. It may also result from accidental or intentional poisoning in both diabetic and nondiabetic patients. The traditional approach to SUA-induced hypoglycaemia includes administration of glucose, and glucagon or diazoxide in those who remain hypoglycaemic despite repeated or continuous glucose supplementation. However, these antidotal approaches are associated with several shortcomings, including further exacerbation of insulin release by glucose and glucagon, leading only to a temporary beneficial effect and later relapse into hypoglycaemia, as well as the adverse effects of both glucagon and diazoxide. Octreotide inhibits the secretion of several neuropeptides, including insulin, and has successfully been used to control life-threatening hypoglycaemia caused by insulinoma or persistent hyperinsulinaemic hypoglycaemia of infancy. Therefore, this agent should in theory also be useful to decrease glucose requirements and the number of hypoglycaemic episodes in patients with SUA-induced hypoglycaemia. This has apparently been confirmed by experimental data, one retrospective study based on chart review, and several anecdotal case reports. There is thus a need for further prospective studies, which should be adequately powered, randomized and controlled, to confirm the probable beneficial effect of octreotide in this setting.  相似文献   
75.
This exploratory study examined the heart rates (HR) and skin temperatures (ST) of 18 preschool children while they viewed two clips of everyday children's television (TV) programming. The measurements were made in a day care setting, in a naturalistic environment designed to mimic the real world of children's TV viewing. The purpose of the study was to determine whether cardiovascular and autonomic arousal to TV programming might occur in some children. Since a large body of psychosocial literature addresses the affects of TV violence on children, HR and ST were examined during exposure to scenes from Mr. Roger's Neighborhood and G.I. Joe cartoons. The Mr. Roger's clip was slow, rhythmic, prosocial, and nonviolent, while the G.I. Joe clip was fast-paced, staccato, colorful, and full of verbal and action violence. The study found a significant effect of exposure to the cartoon violence on HR, with HR increasing. ST decreased, but not significantly, and there was a significant effect of time on the ST, due possibly to habituation. This finding has relevance to nursing assessment, intervention, and education of parents and children, since TV viewing is a pervasive cultural phenomenon. The possibility of excessive or inappropriate autonomic and cardiovascular responsiveness in some children to TV must be considered.  相似文献   
76.

Background

Recent systematic reviews and editorials suggest that many organizations that produce nutritional guideline recommendations do not adhere to internationally recognized standards set forth by the Institute of Medicine (IoM), Guidelines International Network (GIN), Appraisal of Guidelines Research and Evaluation (AGREE), and Grading Recommendations, Assessment, Development and Evaluation (GRADE).

Methods

The potential solution is an independent group with content expertise and skilled in the methodology of systematic reviews and practice guidelines to produce trustworthy guideline recommendations, recommendations that are supported by publication in a top tier journal. The BMJ Rapid Recommendations project has recently demonstrated the feasibility and utility of this approach. Here, we are proposing trustworthy nutritional guideline recommendations based on internationally accepted guideline development standards, recommendations that will be informed by rigorous and novel systematic reviews of the benefits and harms associated with nutritional exposures, as well as studies on the values and preferences related to dietary behaviors among members of the international community.

Discussion

Adhering to international guideline standards, conducting high quality systematic reviews, and actively assessing the values and preferences of key stakeholders is expected to improve the quality of nutritional guidelines and their relevance to end-users, particularly patients and community members. We will send our work for peer review, and if found acceptable, we will publish our nutritional recommendations in top-tier general medicine journals.
  相似文献   
77.
【目的】通过对经住院治疗后下肢深静脉血栓形成(deep venous thrombosis,DVT)患者院外分别继续应用低分子肝素(low molecule weight heparin,LMWH)或维生素K拮抗剂(vitamin K antagonists,VKA)的效益-风险比的对比研究,探讨较为有效、安全、简便的抗凝方案。【方法】将2008年12月-2011年3月符合纳入标准的患者随机分为A组(应用低分子肝素钙)和B组(应用华法林),并随访6个月,期间通过定期监测凝血功能及血小板计数,调整用药方案;每2个月做1次全面随访,包括有无出血、肝素诱导的血小板减少和复发事件的发生。【结果】两组均取得有效的抗凝效果,并且A组副作用发生率在各监测点明显低于B组(P<0.05),随访中发现两组DVT复发率无差异(P>0.05),但随着抗凝时间延长,两组患者出血发生率增加。在DVT复发患者中,髂股深静脉血栓形成者复发率最高,其次是股静脉、腘静脉。患者对应用A治疗方案的依从性较高。【结论】DVT患者院外继续应用LWMH抗凝效果可靠,用药安全性高,副作用较小,操作及监测简单,与应用VKA相比效益-风险比较高。  相似文献   
78.
ObjectivesTo report a case of papillary adenocarcinoma occurring on ectopic thyroid tissue in the hyoid bone region.Material and methodsA 57-year-old patient consulted for a cervical mass appearing 1 year before, with no signs of compression. The thyroid function was normal.ResultsThe examination showed a firm tumefaction, fixed on the hyoid bone, with undetermined limits, measuring approximately 8 cm. The thyroid gland was in the normal pretracheal position. The cervical tomodensitometry objectified an osteolytic process centered on the hyoid bone with a fleshy zone of tissue density and calcifications. Cervical MRI provided a more precise assessment of the extension of the mass and confirmed the integrity of the other structures, in particular the endolarynx. The tumor was totally resected via a cervical approach. The pathologic study suggested a papillary adenocarcinoma on ectopic thyroid tissue. The treatment was completed by a total thyroidectomy with normal histological results.ConclusionsPapillary adenocarcinoma on ectopic thyroid is a very rare situation. Its diagnosis is histological. Its treatment is primarily surgical, sometimes associated with radioiodine I-131 therapy.  相似文献   
79.
Sodium channel NaV1.7, encoded by the SCN9A gene, is preferentially expressed in nociceptive primary sensory neurons, where it amplifies small depolarizations. In studies on a family with inherited erythromelalgia associated with NaV1.7 gain‐of‐function mutation A863P, we identified a nonsynonymous single‐nucleotide polymorphism within SCN9A in the affected proband and several unaffected family members; this polymorphism (c. 3448C&T, Single Nucleotide Polymorphisms database rs6746030, which produces the amino acid substitution R1150W in human NaV1.7 [hNaV1.7]) is present in 1.1 to 12.7% of control chromosomes, depending on ethnicity. In this study, we examined the effect of the R1150W substitution on function of the hNaV1.7 channel, and on the firing of dorsal root ganglion (DRG) neurons in which this channel is normally expressed. We show that this polymorphism depolarizes activation (7.9–11mV in different assays). Current‐clamp analysis shows that the 1150W allele depolarizes (6mV) resting membrane potential and increases (~2‐fold) the firing frequency in response to depolarization in DRG neurons in which it is present. Our results suggest that polymorphisms in the NaV1.7 channel may influence susceptibility to pain. Ann Neurol 2009;66:862–866  相似文献   
80.
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