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The pathological assessment of the resection margin of rectal cancer is important to predict clinical outcome. The transverse slicing method of rectal specimens is recommended in Western countries. However, in Japan the longitudinal slicing method is traditionally advocated. The aim of this study was to assess the advantages of the longitudinal slicing method. The subjects were 197 consecutive patients with primary rectal cancer who underwent curative intersphincteric resection from 2000 to 2013. The resected rectal specimens were cut into 12 slices in the direction of the long axis. Resection margin was considered positive when it was less than or equal to 1 mm. Resection margin was positive in 23 patients (12%). They were classified into two groups, namely the DEEP group (n = 16, 70%), when the resection margin corresponded to the deepest tumor invasion area, and the ENTRY group (n = 7, 30%), when resection margin was around the initial cutting point of the anal canal. It was shown that resection margin tends to be positive not only in the deepest tumor invasion area but also in the entry area of the anal canal. The longitudinal slicing method may have some advantages for accurate assessment of resection margin especially in low‐lying rectal cancer.  相似文献   
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Internal capsule (IC) stimulation has been used clinically to alleviate central pain. However, the neuronal mechanisms underlying pain relief by IC stimulation are poorly understood. In order to elucidate the analgesic mechanism, the effect of IC conditioning stimulation on nociceptive neurons in the rat medullary dorsal horn was investigated in the present study. Rats were anaesthetized with N(2)O-O(2) (2:1) and 0.5% halothane and were immobilized with pancuronium bromide. Two kinds of nociceptive neurons, wide dynamic range (WDR) and nociceptive specific (NS) neurons, responding to noxious stimulations of the face and oral structures were recorded in the trigeminal caudal nucleus and the medial reticular subnuclei. A test stimulus with a single rectangular pulse (2ms in duration, 5-70V) was applied to the centre of the receptive field. Responses in 55.9% of the WDR neurons and in 60% of the NS neurons were inhibited by conditioning stimuli to the ipsilateral IC with trains of 33 pulses (100-300microA) at 330Hz. The percents of peak inhibitory effects on WDR neurons and NS neurons were 78.1+/-25.0% (n=19) and 89.0+/-13.6% (n=3), respectively. The inhibitory effect continued for conditioning-test intervals of up to 500ms. Effective sites for conditioning stimulation were concentrated in the lateral side of the IC. These findings suggest that modulation of nociceptive transmission by IC stimulation occurs at second-order neurons via a presynaptic phenomenon by corticofugal fibers in the IC.  相似文献   
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Angina bullosa hemorrhagica (ABH) is an oral mucosal blood blister that develops without blood dyscrasia or vesiculobullous disorder. Although a minor mucosal trauma has been suggested as a triggering factor for ABH, its etiopathogenesis, especially the causative role of systemic conditions, is largely unknown. We investigated the presence or absence of local factors as well as systemic background disease in 16 patients with ABH arising in the soft palate. All the lesions were solitary, and 75% of them (n = 12) appeared during the ingestion of hard or crispy food. With regard to underlying systemic conditions, hypertension was the most common (n = 6), and asthma, insomnia, diabetes mellitus, rheumatoid arthritis, gastrointestinal disorder and hyperuricemia were also recorded (n = 1 each). Five patients had no significant background disease. There were no recalcitrant or recurrent cases. In conclusion, the present study has revealed that scratching of the oral mucosa during eating plays an important role in the formation of ABH. Hypertension appears to be the most frequent background condition, but its pathogenic relationship with ABH remains speculative, as hypertension is fairly common in adults.  相似文献   
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To assess the usefulness of CT images for the diagnosis of suspected odontogenic maxillary sinusitis, 52 patients with maxillary sinusitis who had received CT examination were retrospectively analyzed. maxillary sinus ostium was established on coronal CT image in 20 out of 55 lesions in those 52 patients. However, a considerable number of patients who had inflammatory disease not only in the maxillary sinus but also in other paranasal sinuses (38/55) or in the nasal meatus (34/55) were included in those 52 patients. Concerning the opening of the ostium, the clinical diagnosis is frequently different from the diagnosis made using CT. The CT findings of the maxillary sinus ostium, nasal meatus and other paranasal sinuses were thus important in planning the treatment for patients with maxillary sinusitis in dentistry, as in otorhinolaryngology.  相似文献   
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The aim of the present study was to explore the unfavorable subset of patients with Stage II gastric cancer for whom surgery alone is the standard treatment (T1N2M0, T1N3M0, and T3N0M0). Recurrence-free survival rates were examined in 52 patients with stage T1N2-3M0 and stage T3N0M0 gastric cancer between January 2000 and March 2010. Univariate and multivariate analyses were performed to identify risk factors using a Cox proportional hazards model. The recurrence-free survival (RFS) rates of the patients with stages T1N2, T1N3, and T3N0 cancer were 80.0, 76.4, and 100% at 5 years, respectively. The only significant prognostic factor for the survival rates of the patients with stage pT1N2-3 cancer measured by univariate and multivariate analyses was pathological tumor diameter. The 5-year RFS rates of the patients with stage pT1N2-3 cancer were 60.0%, when the tumor diameters measured <30 mm, and 88.9% when the tumor diameters measured >30 mm (P = 0.0248). These data may suggest that pathological tumor diameter is associated with poor survival in patients with small T1N2-3 tumors. Because our study was a retrospective single-center study with a small sample size, a prospective multicenter study is necessary to confirm whether small tumors are risk factor for the RFS in T1N2-3 disease.Key words: Gastric cancer, Stage II, Adjuvant chemotherapyEvery year, more than 934,000 people develop gastric cancer worldwide. After lung cancer, gastric cancer is the second most frequent cancer-related cause of death.1 Complete resection is essential to cure gastric cancer. Patients with stage II or stage III gastric cancer often develop tumor recurrence, even after complete curative resections.In 2007, the Adjuvant Chemotherapy Trial of S-1 for Gastric Cancer (ACTS-GC) phase III trial demonstrated that S-1 is effective as adjuvant chemotherapy in Japanese patients who have undergone curative D2 gastrectomy for advanced gastric cancer.2 In general, patients eligible for ACTS-GC were those diagnosed with pathological stages II and III. However, patients classified with pathological (p) stages T1N2M0, T1N3M0, and T3N0M0—which are classified as part of stage II—were excluded from the ACTS-GC trial. Because in the prior phase III studies comparing surgery alone and adjuvant chemotherapy, patients with stages T1N+ and T2-3/N0 cancer had excellent prognoses with 5-year overall survival (OS) rates of more than 80% from surgery alone,3,4 these patients were excluded from receiving adjuvant chemotherapy. Japanese Gastric Cancer Association (JGCA) guidelines clearly state that the standard treatment for these patients is surgery alone.5Therefore, patients with stage II gastric cancer have been divided into two groups: one for whom the standard treatment is surgery alone, and the other for whom the standard treatment is surgery and adjuvant chemotherapy with S-1. Before the advent of ACTS-GC, survival rates were poorer in the latter group than in the former. However, treatment with adjuvant chemotherapy with S-1 has reversed this trend. Now, patients in the latter group receiving S-1 adjuvant chemotherapy have 5-year OS rates of 84.2%.6 Therefore, it may be old rationale that dictates that patients in the former group should be excluded from receiving adjuvant chemotherapy, because the 5-year OS rates are now more than 80% by S-1 adjuvant chemotherapy in the latter group. Five-year OS rates of 80% would not be obtained by surgery alone. Among those patients with stage II gastric cancer assigned to the surgery alone group, some may have a poor prognosis and be good candidates for adjuvant chemotherapy. The aim of the present study was to explore the unfavorable subset of patients among those with stage II gastric cancer for whom surgery alone is the standard treatment (T1N2M0, T1N3M0, and T3N0M0).  相似文献   
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