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Breast elastography has been available for more than 15 years but is not widely incorporated into clinical practice. Many publications report extremely high accuracy for various breast elastographic techniques. However, results in the literature are extremely variable. This variability is most likely due to variations in technique, a relatively steep learning curve, and variability in methods between vendors. This article describes our protocol for performing breast elastography using both strain elastography and shear wave elastography, which produces high sensitivity and specificity. Additionally, we will describe the most commonly known false-positive and false-negative lesions as well as how to detect them.  相似文献   
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The term “oligometastatic prostate cancer” refers to a heterogeneous group of disease states currently defined solely on the basis of clinical features. Oligorecurrent disease, de novo oligometastases, and oligoprogressive disease likely have unique biologic underpinnings and natural histories. Evidence suggesting the existence of a subset of patients who harbor prostate cancer with limited metastatic potential currently includes disparate and overwhelmingly retrospective reports. Nevertheless, emerging prospective data have corroborated the “better-than-expected,” retrospectively observed outcomes, particularly in the setting of oligorecurrent prostate cancer. Improved functional imaging with prostate-specific membrane antigen-targeted strategies may enhance the identification of patients with oligometastatic prostate cancer in the short term. In the long term, refinement of the oligometastatic case definition likely will require biologic risk-stratification schemes. To determine optimal treatment strategies and identify patients most likely to benefit from metastasis-directed therapy, future efforts should focus on conducting high-quality, prospective trials with much-needed molecular correlative studies.  相似文献   
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Melatonin receptors play important roles in the regulation of circadian and seasonal rhythms, sleep, retinal functions, the immune system, depression, and type 2 diabetes development. Melatonin receptors are approved drug targets for insomnia, non‐24‐hour sleep‐wake disorders, and major depressive disorders. In mammals, two melatonin receptors (MTRs) exist, MT1 and MT2, belonging to the G protein‐coupled receptor (GPCR) superfamily. Similar to most other GPCRs, reliable antibodies recognizing melatonin receptors proved to be difficult to obtain. Here, we describe the development of the first monoclonal antibodies (mABs) for mouse MT1 and MT2. Purified antibodies were extensively characterized for specific reactivity with mouse, rat, and human MT1 and MT2 by Western blot, immunoprecipitation, immunofluorescence, and proximity ligation assay. Several mABs were specific for either mouse MT1 or MT2. None of the mABs cross‐reacted with rat MTRs, and some were able to react with human MTRs. The specificity of the selected mABs was validated by immunofluorescence microscopy in three established locations (retina, suprachiasmatic nuclei, pituitary gland) for MTR expression in mice using MTR‐KO mice as control. MT2 expression was not detected in mouse insulinoma MIN6 cells or pancreatic beta‐cells. Collectively, we report the first monoclonal antibodies recognizing recombinant and native mouse melatonin receptors that will be valuable tools for future studies.  相似文献   
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Objective: Several biologic therapies are available for the treatment of mild-to-moderate Crohn’s disease (CD). This network meta-analysis (NMA) aimed to assess the comparative efficacy of ustekinumab, adalimumab, vedolizumab and infliximab in the maintenance of clinical response and remission after 1?year of treatment.

Methods: A systematic literature search was performed to identify relevant randomized controlled trials (RCTs). Key outcomes of interest were clinical response (CD activity index [CDAI] reduction of 100 points; CDAI-100) and remission (CDAI score under 150 points; CDAI < 150). A treatment sequence Bayesian NMA was conducted to account for the re-randomization of patients based on different clinical definitions, the lack of similarity of the common comparator for each trial and the full treatment pathway from the induction phase onwards.

Results: Thirteen RCTs were identified. Ustekinumab 90?mg q8w was associated with statistically significant improvement in clinical response relative to placebo and vedolizumab 300?mg. For clinical remission, ustekinumab 90?mg q8w was associated with statistically significant improvement relative to placebo and vedolizumab 300?mg q8w. Findings from sub-population analyses had similar results but were not statistically significant.

Conclusions: The NMA suggest that ustekinumab is associated with the highest likelihood of reaching response or remission at 1?year compared with placebo, adalimumab and vedolizumab. Results should be interpreted with caution because this is a novel methodology; however, the treatment sequence analysis may be the most methodologically sound analysis to derive estimates of comparative efficacy in CD in the absence of head-to-head evidence.  相似文献   

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