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Background

The purposes of this study were to clarify the risk factors for supraclavicular lymph node (SCLN) metastasis and the survival benefit from cervical lymph node (LN) dissections in patients with clinically submucosal (cT1b) carcinoma of the thoracic esophagus.

Methods

A total of 86 patients with this disease who underwent esophagectomy with 3-field lymph node dissection were retrospectively reviewed. Multivariate logistic regression and Cox proportional hazard model were used to identify the independent risk factors for SCLN metastasis and prognostic factors, respectively. An index calculated by multiplying the frequency of metastasis at nodal basin and the 5-year overall survival rate of patients with metastasis at that basin were used to assess the therapeutic outcomes.

Results

A total of 40 patients (47 %) were found to have pathological LN metastasis. Also, 13 patients (15 %) had cervical LN metastasis: 6 and 7 with carcinoma of the upper and mid-thoracic esophagus, respectively. SCLN metastasis was found in 6 patients (7 %); however, there was no independent risk factor for SCLN metastasis. The 5-year overall survival rate was 72.5 %. Cervical LN metastasis was an independent prognostic factor (p = .04; odds ratio 2.55; 95 % confidence interval 1.03–6.31); however, there was no significant difference in survival between patients with SCLN metastasis and those without (p = .06). The calculated index of estimated benefit from cervical LN dissections was 6.9, following upper mediastinal LN of 15.6 and perigastric LN of 8.3.

Conclusions

We could not identify risk factors to predict SCLN metastasis. Cervical LN dissection should not be omitted in patients with cT1b carcinoma, especially of the upper and mid-thoracic esophagus.  相似文献   
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Annals of Nuclear Medicine - The objective of the present study was to develop a fully automated blood sampling system for kinetic analysis in mice positron emission tomography (PET) studies....  相似文献   
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Diagnostic imaging is undoubtedly important in modern medicine, and final clinical decisions are often made based on it. Fortunately, Japan has the highest numbers of diagnostic imaging instruments, such as CT and MRI devices, and boasts easy access to them as well as a high level of diagnostic accuracy. In consequence, a very large number of imaging examinations are performed, but diagnostic instruments are installed in so many medical facilities that expert management of these examinations tends to be insufficient. Particularly, in order to avoid risks, clinicians have recently become indifferent to indications of imaging modalities and tend to rely on CT or MRI resulting in increasing the number of imaging examinations in Japan. This is a serious problem from the viewpoints of avoidance of unnecessary exposure and medical economy. Under these circumstances, the Japan Radiological Society and Japanese College of Radiology jointly initiated the preparation of new guidelines for diagnostic imaging. However, the field of diagnostic imaging is extremely wide, and it is impossible to cover all diseases. Therefore, in drafting the guidelines, we selected important diseases and focused on “showing evidence and suggestions in the form of clinical questions (CQs)” concerning clinically encountered questions and “describing routine imaging techniques presently considered to be standards to guarantee the quality of imaging examinations”. In so doing, we adhered to the basic principles of assuming the readers to be “radiologists specializing in diagnostic imaging”, “simultaneously respecting the global standards and attending to the situation in Japan”, and “making the guidelines consistent with those of other scientific societies related to imaging”. As a result, the guidelines became the largest ever, consisting of 152 CQs, nine areas of imaging techniques, and seven reviews, but no other guidelines in the world summarize problems concerning diagnostic imaging in the form of CQs. In this sense, the guidelines are considered to reflect the abilities of diagnostic radiologists in Japan. The contents of the guidelines are essential knowledge for radiologists, but we believe that they are also of use to general clinicians and clinical radiological technicians. While the number and contents of CQs are still insufficient, and while chapters such as those on imaging in children and emergency imaging need to be supplemented, the guidelines will be serially improved through future revisions. Lastly, we would like to extend our sincere thanks to the 153 members of the drafting committee who authored the guidelines, 12 committee chairpersons who coordinated their efforts, six members of the secretariat, and affiliates of related scientific societies who performed external evaluation.  相似文献   
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We examined the time course of apparent motion and apparent displacement of a visual target, and also the horizontal deviation of apparent straight-ahead related to left-posterior neck-muscle vibration. In Experiment 1, eight observers verbally judged the apparent motion and displacement of a visual target for 60 s from prior to the vibration to after its offset. We found that rightward apparent motion was an almost identical in magnitude during the vibration and disappeared within 20 s after the vibration offset. In contrast, rightward apparent displacement gradually increased during the vibration, and was sustained over 40 s after the vibration offset. In Experiment 2, five observers manually pointed to the position of a visual point in the median plane; the mean pointed position in the vibration condition was found to deviate maximally 3 degrees to the right of the mean pointed position in the control condition. In Experiment 3, the same observers closed their eyes and pointed to the apparent straight-ahead; the mean pointed positions did not differ between the vibration and control conditions.  相似文献   
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In this study, we performed urinary metabolic fingerprinting using Fourier transform-ion cyclotron resonance mass spectrometry (FT-ICR MS) in the thioacetamide (TAA)-induced rat model of acute hepatic injury to search for useful biomarkers involved in the acute hepatic toxicity. TAA was intraperitonealy administered a single dose of 300 mg/kg, and urine sample and livers were collected on predose, and days 1, 3, 5, and 7 postdose (Days 1, 3, 5, and 7). Histopathologically, infiltration of macrophages occurred in the TAA-induced centrilobular injured area on Days 1 and 3, and the injured liver recovered on Days 5 and 7. On the scores plot of principal component analysis (PCA), the ion profiles of Days 1 and 3 were different from those of the predose, Days 5 and 7. The loading plot revealed that the metabolites causing PCA results were m/z 266.05390, 401.20737, and 429.23882. The ion at m/z 266.05390 was identified as a potassium ion adduct of deoxycytidine (dCyt). Because the appearance of urinary dCyt was corresponding to macrophage infiltration in the rat-injured liver, it was considered that the urinary dCyt might be released from infiltrated macrophages. dCty might be a biomarker for the acute hepatotoxicity in rats.  相似文献   
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