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Dermal melanocytosis refers to a spectrum of benign melanocytic proliferations that includes Mongolian spot, nevus of Ota and nevus of Ito. These lesions most commonly occur in persons of Asian or African descent and are often present at birth or develop during childhood. Very rarely, dermal melanocytoses undergo malignant transformation. There have been only 13 reports in the literature of primary cutaneous melanoma arising in dermal melanocytoses. We report a case of a Chinese woman with melanoma arising in a congenital nevus of Ito. We performed targeted next‐generation sequencing of the tumor which revealed mutations of GNAQ and BAP1, suggesting that alterations in these two genes led to malignant transformation of the nevus of Ito. We also provide a summary of reports in the literature regarding primary cutaneous melanoma arising in the context of dermal melanocytosis.  相似文献   
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Guidelines now discourage opioid analgesics for chronic noncancer pain because the benefits frequently do not outweigh the harms. We aimed to determine the proportion of patients with chronic noncancer pain who are prescribed an opioid, the types prescribed and factors associated with prescribing. Database searches were conducted from inception to 29 October 2018 without language restrictions. We included observational studies of adults with chronic noncancer pain measuring opioid prescribing. Opioids were categorized as weak (e.g. codeine) or strong (e.g. oxycodone). Study quality was assessed using a risk of bias tool designed for observational studies measuring prevalence. Individual study results were pooled using a random‐effects model. Meta‐regression investigated study‐level factors associated with prescribing (e.g. sampling year, geographic region as per World Health Organization). The overall evidence quality was assessed using Grading of Recommendations Assessment, Development and Evaluation criteria. Of the 42 studies (5,059,098 participants) identified, the majority (n = 28) were from the United States of America. Eleven studies were at low risk of bias. The pooled estimate of the proportion of patients with chronic noncancer pain prescribed opioids was 30.7% (95% CI 28.7% to 32.7%, n = 42 studies, moderate‐quality evidence). Strong opioids were more frequently prescribed than weak (18.4% (95% CI 16.0–21.0%, n = 15 studies, low‐quality evidence), versus 8.5% (95% CI 7.2–9.9%, n = 15 studies, low‐quality evidence)). Meta‐regression determined that opioid prescribing was associated with year of sampling (more prescribing in recent years) (P = 0.014) and not geographic region (P = 0.056). Opioid prescribing for patients with chronic noncancer pain is common and has increased over time.  相似文献   
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Although the 2017‐2018 influenza season had very high rates of influenza‐associated illness, the 2018‐2019 influenza season was comparable to previous seasons. Influenza A was the most commonly identified type worldwide, although variations in influenza A subtype prevalence existed. Influenza vaccination remains the single most effective way to prevent influenza‐associated illness. A novel influenza antiviral, baloxavir, has demonstrated promising results; however, concerns about development of resistance exist.  相似文献   
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This review describes the indications and contraindications for endoscopic biopsy, in routine practice, of the upper gastrointestinal (GI) tract. We accept that this review provides grounds for controversy, as our stance in certain situations is counter to some national guidelines. Nevertheless, we provide evidence to support our viewpoints, especially on efficiency and economic grounds. We describe the particular controversies concerning the biopsy assessment of Barrett's oesophagus, chronic gastritis and the duodenum in the investigation of coeliac disease. We accept that there are indications for more extensive upper GI biopsy protocols in children than in adults; the latter constitute our main focus in this article. We would encourage detailed discussion between pathologists and their endoscopy colleagues about the indications, or lack of them, for routine upper GI endoscopic biopsy, as studies have shown that adherence to agreed guidelines has resulted in a very considerable diminution in the biopsy workload without compromising patient management. Furthermore, where biopsy is indicated, we emphasise the importance of accompanying clinical information provided to the pathologist, in particular regarding biopsy site(s), and regular feedback to endoscopists to improve and maintain the quality of such information. Finally, local dialogue is also advised, when necessary, to indicate to endoscopists the need to appropriately segregate biopsies into separate, individually labelled specimens, to maximise the information that can be derived by pathological evaluation and thereby improve the quality of the final pathology report.  相似文献   
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ObjectiveThe implementation of medical aid-in-dying (MAID) poses new challenges for clinical communication and counseling. Among these, health care providers must consider whether to initiate a discussion of MAID with eligible patients who do not directly ask about it. Norms and policies concerning this issue vary tremendously across jurisdictions where MAID is legally authorized, reflecting divergent assumptions about patients’ rights to information about end-of-life options and the purpose and potential harms of clinical disclosure.MethodThis discussion forum essay draws on informed consent doctrine to analyze two policies concerning clinical communication about MAID: the legal prohibition against provider-initiated discussions of MAID in Victoria, Australia, and the Canadian Association of MAID Assessors and Providers (CAMAP) position that providers have an ethical and professional responsibility to inform eligible patients about MAID.ConclusionsInformed consent requires that clinicians strike a balance between minimizing potential harms to patients caused by initiating discussions of MAID and the imperative to inform and counsel patients about all of their legally available medical options.Practice implicationsClinicians should be aware of both the importance of communication as a tool to inform patients and the potential for clinical language to cause harm to or to unduly influence patients.  相似文献   
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