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BackgroundPancreatic ductal adenocarcinoma (PDAC) has poor survival. Current treatments offer little likelihood of cure or long-term survival. This systematic review evaluates prognostic models predicting overall survival in patients diagnosed with PDAC.MethodsWe conducted a comprehensive search of eight electronic databases from their date of inception through to December 2019. Studies that published models predicting survival in patients with PDAC were identified.Results3297 studies were identified; 187 full-text articles were retrieved and 54 studies of 49 unique prognostic models were included. Of these, 28 (57.1%) were conducted in patients with advanced disease, 17 (34.7%) with resectable disease, and four (8.2%) in all patients. 34 (69.4%) models were validated, and 35 (71.4%) reported model discrimination, with only five models reporting values >0.70 in both derivation and validation cohorts. Many (n = 27) had a moderate to high risk of bias and most (n = 33) were developed using retrospective data. No variables were unanimously found to be predictive of survival when included in more than one study.ConclusionMost prognostic models were developed using retrospective data and performed poorly. Future research should validate instruments performing well locally in international cohorts and investigate other potential predictors of survival.  相似文献   
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BackgroundRhythmic joint mobilizations (RJM) of the temporomandibular joint (TMJ) are employed to relieve pain and improve function in patients with temporomandibular disorders (TMD). However, the evidence on the immediate effects of RJM in patients with TMD is scarce. The aim of this study was to assess the immediate clinical and functional effects of RJM in patients with TMD.Materials and methodsThis was a one-group quasi-experimental before and after study. Thirty-eight patients with TMD were assessed by means of pain intensity (visual analogue score, VAS), pressure pain threshold (PPT, measured through pressure algometry on the masseter and temporal muscles), mouth opening (MO, measured with a ruler), and surface electromyographic activity of the masseter and temporal muscles (asymmetry index, AI). Measurements were performed before and after a single, 1-min session of RJM of each TMJ. All statistical analyses were performed using the SPSS version 20.0 statistical package.ResultsA statistical significant difference was found in pain intensity, PPT and MO after the intervention (p < 0.05). No difference was found in the AI. A large effect size was observed for pain intensity, PPT of the left and right masseter muscles and MO (d = 0.85–1.13), whereas for the left and right temporal muscles the effect size was moderate (d = 0.62) and small, respectively (d = 0.49).ConclusionIn this sample of patients with TMD, a single session of RJM of the TMJ seemed to be effective in reducing pain intensity, increasing PPT and improving MO immediately after the intervention, without differences in the AI.  相似文献   
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Cerebrotendinous xanthomatosis (CTX), sitosterolemia, and Smith-Lemli Opitz syndrome (SLOS) are rare inborn errors of metabolism. The diagnoses of CTX and sitosterolemia are often delayed for many years because of lack of physician awareness, often resulting in significant and unnecessary progression of disease. CTX may present with chronic diarrhea, juvenile onset cataracts, strikingly large xanthomas, and neurologic disease in the setting of a normal serum cholesterol, but markedly elevated serum or plasma cholestanol levels. These patients have a defect in producing the bile acid chenodoxycholate, and oral chenodeoxycholate therapy is essential for these patients in order to prevent neurologic complications. Sitosterolemia can present with xanthomas, anemia, thrombocytopenia, splenomegaly, very premature heart disease, and serum cholesterol levels that may be normal or elevated, along with marked elevations of plasma β-sitosterol. These patients have a defect causing overabsorption of β-sitosterol, and the treatment of choice is oral ezetimibe. SLOS presents with growth delay, intellectual disability, multiple structural anomalies, and low serum cholesterol levels, and the defect is reduced cholesterol production. Treatment consists of dietary cholesterol supplementation and oral bile acid therapy which raises serum cholesterol levels and may improve symptoms. The metabolic and genetic defects in these disorders have been defined. There is no one in our field that has contributed more to the diagnosis and treatment of these disorders than Gerald Salen, MD, who died in late 2020 at 85 years of age. He will be greatly missed by his family, friends, and colleagues from around the world.  相似文献   
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Correctly diagnosing the cause of wide QRS tachycardias remain an area of difficulty for many clinicians. The authors provide a concise update to the different ECG algorithms that have been developed as well as caveats in their application.  相似文献   
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