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Macroscopic diagnosis for lymph node metastases was compared with histopathological diagnosis in 444 patients with carcinoma of the esophagus, stomach, colon, thyroid and breast. The former indicated lymph node metastases in 181 patients. In all of them, none or less than five node metastases were proven by routine histopathological diagnosis. Detailed histological study revealed lymph node metastases in 25 out of 263 patients with macroscopically negative nodes, the rate of false negative being 9.5 per cent. The study also demonstrated no lymph node metastases in 51 of 181 patients with macroscopically positive nodes. Three additional specimens were obtained from originally examined 693 lymph nodes and reexamined microscopically in these 51 patients. Involvement by cancer cells was detected in 9 nodes (1.3 per cent) in 8 patients. Metastases were found from additional specimens in 7 of 9 nodes, indicating that metastatic carcinoma had been overlooked in the remaining two nodes. Additional specimens or embedding-techniques were recommended in such cases as macroscopic metastases were strongly suspected or lymph vessel invasions were remarkable. In 24 patients with esophageal cancer, one to one correspondence was available in the analysis of macroscopic diagnosis. Seventy-eight out of 108 involved nodes were macroscopically judged as involved (sensitivity; 72.2 per cent), and 1166 out of 1260 nodes without macroscopical metastases were judged as cancer-free (specificity; 92.5 per cent). Overestimation of macroscopic diagnosis was due to thickened capsule, fibrosis, inflammation and enlargement in size more than 10 mm in diameter of the nodes. Underestimation was observed in case of nodes with metastatic area less than one-third and with smaller size less than 5mm in diameter.  相似文献   
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Effects of nilvadipine on the low- and high-voltage activated Ca2+ currents (LVA and HVA ICa, respectively) were compared with other organic Ca2+ antagonists in acutely dissociated rat hippocampal CA1 pyramidal neurons. The inhibitory effects of nilvadipine, amlodipine and flunarizine on LVA ICa were concentration- and use-dependent. The apparent half-maximum inhibitory concentrations (IC50s) at every 1- and 30-s stimulation were 6.3×10−7 M and 1.8×10−6 M for flunarizine, 1.9×10−6 M and 7.6×10−6 M for nilvadipine, and 4.0×10−6 M and 8.0×10−6 M for amlodipine, respectively. Thus, the strength of the use-dependence was in the sequence of nilvadipine>flunarizine>amlodipine. Nilvadipine also inhibited the HVA ICa in a concentration-dependent manner with an IC50 of 1.5×10−7 M. The hippocampal CA1 neurons were observed to have five pharmacologically distinct HVA Ca2+ channel subtypes consisting of L-, N-, P-, Q- and R-types. Nilvadipine selectively inhibited the L-type Ca2+ channel current which comprised 34% of the total HVA ICa. On the other hand, amlodipine non-selectively inhibited the HVA Ca2+ channel subtypes. These results suggest that the inhibitory effect of nilvadipine on the neuronal Ca2+ influx through both LVA and HVA L-type Ca2+ channels, in combination with the cerebral vasodilatory action, may prevent neuronal damage during ischemia.  相似文献   
4.
A 51 -year-old woman with mixed growth hormone (GH) cell-prolactin (PRL) cell pituitary adenoma is presented. She had clinical signs due to hypersecretion of GH and PRL. Resected tissue was studied immunohistochemically and morphologically. The serial sections revealed that GH and α-subunit were co-localized in most cells, while GH and PRL were localized in different cells.  相似文献   
5.
Enzyme-linked immunosorbent assay (ELISA) was applied to the detection of IgG and IgM antibodies against outer membrane vesicles (OMV) antigen ofHaemophilus influenzae type b. In this ELISA system, IgG antibody titers were about 40 fold higher than those in indirect hemagglutination assay (IHA). The IgG antibody titers by this ELISA of rabbit sera obtained after immunization were comparable with those by radioimmunoassay (RIA) of the same sera. A significant correlation was established between these two assays (r=0.973,P<0.001).Subject section: Bacteriology (infection and immunity)  相似文献   
6.
We report a rare case of sudden hemorrhage caused by breast cancer. A 70-year-old Japanese woman noted fresh bleeding from her left breast. On physical examination, continuous hemorrhage accompanied by an open cavity was observed in the left breast. Mammography and ultrasonography revealed a well-circumscribed mass, with solid and cystic components, that was highly suggestive of intracystic breast carcinoma with direct skin invasion. Computed tomography and bone scintigraphy showed no distant metastasis. Aspiration biopsy of the lesion showed several clusters of adenocarcinoma cells. Modified radical mastectomy was performed with a presumptive diagnosis of stage III B left breast cancer. Invasive ductal carcinoma without skin invasion was diagnosed histologically. To the best of our knowledge, only 6 other cases of sudden hemorrhage caused by breast cancer without skin invasion have been reported in Japan. We review the literature and discuss the clinical characteristics of this unusual phenomenon.  相似文献   
7.

Background and aims

Recently, several new endoscopic instruments have been developed. However, even with the full use of current modalities, the safety of endoscopic surgery is not guaranteed. Information regarding factors such as fibrosis and the blood vessels under the mucosa is very important for avoiding procedure-related complications. The aim of this study was to define the detailed anatomy of the gastric wall structure in vivo using original endoluminal radiofrequency coils for safer endoscopic therapy.

Methods

Swine were used as the subjects and controlled with general anesthesia. Anatomical images were obtained with T1-weighted fast spin echo (T1FSE) and T2-weighted fast spin echo (T2FSE). Dynamic magnetic resonance (MR) angiography was also obtained with three-dimensional T1-weighted fast spoiled gradient recalled acquisition in the steady state (3D-DMRA) following the injection of hyaluronic acid sodium into the submucosal layer.

Results

Porcine gastric wall structure was visualized, and four layers were discriminated in the T1FSE and T2FSE images. The vascular structure was clearly recognized in the submucosa on 3D-DMRA.

Conclusion

Endoluminal MR imaging was able to visualize the porcine stomach with similar quality to endoscopic ultrasonography imaging. Additionally, it was possible to visualize the vascular structures in the submucosal layer. This is the first report to show that blood vessels under the gastric mucosa can be depicted in vivo.  相似文献   
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PurposeThis study aimed to examine how coverage of the hard palate by an experimental palatal plate influenced thermosensation.MethodsA total of 20 young adult volunteers were recruited from Osaka University Graduate School of Dentistry. An experimental palatal plate, 1.5 mm in thickness, was made for each subject from acrylic resin. The stimulus water were either warmed to 40, 42, 44, 46, or 48 °C or cooled to 30, 26, 22, 18, or 14 °C in a constant-temperature water bath, and the control water were maintained at 37 °C. Subjects were instructed to retain the control water in their mouths for 5 s, then to spit it out and to repeat with the stimulus water. They then rated the intensity of stimulation of warmth or cold compared to the control water by the magnitude estimation method. Each stimulus was administered three times in random order. Two experimental conditions were set: with and without the experimental palatal plate.ResultsPerceived thermal intensity was measured as the slope of the regression line for each condition (with or without the experimental palatal plate, cold or warmth). There was a significant difference between with and without the experimental palatal plate; the regression slope with the plate was shallower than that without the plate (warmth perception with plate = 0.55 ± 0.21 vs. warmth perception without plate = 0.70 ± 0.23, P < 0.05; cold perception with plate = –0.33 ± 0.14 vs. cold perception without plate = –0.39 ± 0.11, P < 0.05).ConclusionThe findings suggested that a denture covering the hard palate obstructs thermal perception.  相似文献   
10.
Desmoglein I (DGI) is major component of the desmosomal membrane core that plays an important role in epithelial cell adhesion. The aim of this study was to explore the correlation between the expression of DGI and the clinicopathological findings of esophageal cancer. DGI expression was immunohistochemically examined using an anti-DGI monoclonal antibody in 139 patients with squamous cell carcinoma of the esophagus. Normal squamous epithelial cells strongly expressed DGI at their cell-cell boundaries. According to the intensity and pattern of DGI expression, the cancerous tissues were divided into three groups: DGI (++), DGI (+), and DGI (-). Of the 139 tumors, 35 (25%) were DGI (++), 65 (47%) were DGI (+), and 39 (28%) were DGI (-). A good inverse correlation between DGI expression and tumor invasion, lymph node metastasis, lymphatic invasion, and vessel invasion was observed. These results indicate that DGI expression may be a significant factor for invasion, metastasis, and prognosis of human esophageal cancer. © 1994 Wiley-Liss, Inc.  相似文献   
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