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31.
32.
Abstract A male infant with bilateral small kidneys associated with both proximal and distal tubular dysfunction, who showed chronic renal failure soon after birth, is reported. He was also noted to have both proximal and distal type of renal tubular acidosis. The small kidneys were thought to be due to renal hypodysplasia associated with bilateral severe vesicoureteral reflux, by radiological findings. An alkalization therapy with chemo-prophylaxis seemed to be of benefit in slowing the progression of renal failure in this case.  相似文献   
33.
Cells of the human tumor cell line RMG-1, derived from a clear-cell adenocarcinoma of the ovary, were injected intraperitoneally into nude mice, and the cells obtained from the tumor nodules in the mesenterium were found to form a larger number of, and larger-sized, tumor nodules than the original RMG-1 cells. The RMG-1-h cells, transferred into culture from the tumor nodules after a 4th in vivo passage, showed a dissemination potential as high as that of cells disseminating directly from the tissues, and exceedingly higher than that of RMG-1 cells. To assess the molecular bases of the different biological properties of RMG-1 and RMG-1-h cells, we compared the content and expression of various carbohydrate antigens in both cells. The chromosomal profile of RMG-1-h cells revealed their human origin and was identical to that of the original RMG-1 cells. In contrast to the broad histogram for the Lex-bearing cells among RMG-1 cells in flow cytometry, the weakly and moderately positive cells toward anti-Lex antibody were found to be eliminated from the histogram for the RMG-1-h cells, resulting in the enrichment of cells strongly expressing Lex, which may account for the high dissemination potential. In addition, the adhesion of RMG-1 cells to mesothelial cells was found to be significantly inhibited by pretreatment of the cells with anti-Lex antibody, indicating Lex-mediated cell-to-cell interaction between ovarian cancer cells and mesothelial cells. By TLC-immunostaining, two Lex-glycolipids, III3Fucα-nLc4Cer and V3Fucα-nLc6Cer were detected in both RMG-1 and RMG-1-h cells, and their total concentrations were not significantly different from each other. However, the hydrophobic moieties of Lex-glycolipids in RMG-1-h cells were different from those in RMG-1 cells, suggesting that a difference in the structure of the hydrophobic moieties of Lex is partly involved in the enhanced reactivity of RMG-1-h cells toward anti-Lex antibody. Thus, the high dissemination potential of ovarian cancer cells was shown to be mediated by the Lex-determinant and the Lex-bearing cells are enriched by repeated in vivo passage of the cells into nude mice.  相似文献   
34.
Primary intrapulmonary thymomas are defined as primary thymomas arising in an intrapulmonary location without an associated mediastinal component, and they are very rare. A total of 20 cases have been reported only sporadically in the English literature since 1951. We reported the case of 41-year-old woman who had a 3.5 x 3.0 x 3.0 cm lower right lobe mass with nodal metastasis that extended over the left atrium. We also summarized the clinicopathological features of a total of 21 cases and discussed the problems involved with diagnosis, pathogenesis and treatment. Knowledge of the biological behavior of primary intrapulmonary thymomas is limited because of their rarity. In particular, the issue of the need for lymph node dissection has not been adequately discussed. In this case, pathohistological examination revealed that the routes of lymphatic spread and the sites of noda metastases from primary intrapulmonary thymoma resemble those of primary lung cancer. Therefore, systematic mediastinal lymph node dissection according to the lymph node map for primary lung cancer should be recommended for malignant cases.  相似文献   
35.
AIMS: The objective of this study was to determine whether the maternal surface of the placenta is fractal, and whether the mean fractal dimension differs according to the gestational age and clinically or pathologically different conditions. METHODS: Using digitized images of the maternal surface of 75 placentas, fractal dimensions were measured with a fractal analysis software. RESULTS: The mean fractal dimension of the maternal surface of the placentas significantly exceeded the topological dimension of a surface (= 2). This means that the morphological pattern of the maternal surface fulfills the mathematical definition of fractal structures. Among the three different groups of gestational age, the mean fractal dimension in 22-29 weeks was significantly lower than that in 30-36 and 37-41 weeks (p = 0.022 and 0.014, respectively). Although not significantly different (p = 0.149), in 30-36 weeks the mean fractal dimension of the placentas complicated by pregnancy-induced hypertension (PIH) was greater than that without PIH. CONCLUSION: Fractal geometry, a vocabulary of irregular shapes, can be useful for describing quantitatively the architecture of the maternal surface of the placenta and become a useful tool for analyzing physiological and pathological placental formation mathematically.  相似文献   
36.
The novel coronavirus-19 (COVID-19) pandemic has considerably impacted children’s lives. The aim of this study was to determine whether the pandemic affected mealtime regularity among preschool children and whether maintaining regular mealtimes or changes in mealtime regularity during the pandemic were related to dietary balance, including chronological relationships. This online cross-sectional survey involving individuals registered with a company that provides meals to children aged 2−6 years was conducted in February 2021. Using a 40-point scale, a healthy diet score (HDS) was developed to evaluate children’s dietary balance. The participants were divided into four groups based on their responses, and multiple regression analyses were performed with the HDS as the dependent variable. Maintaining regular mealtimes was associated with practices such as waking and going to bed earlier, less snacking, and eating breakfast every day. Even after adjusting for basic attributes, lifestyle habits, household circumstances, and other factors, regular mealtimes were still positively correlated with the HDS. These findings indicate that maintaining regular mealtimes is associated with higher HDS scores and better lifestyle habits. Furthermore, as the changed HDS was higher in the group whose mealtimes became regular during the pandemic, adopting regular mealtimes may lead to a more balanced diet.  相似文献   
37.
Purpose  The aim of this study was to assess the variation of probe rotation angles for detecting a single needle using sagittal images of transrectal ultrasonography (TRUS). Materials and methods  A phantom study was performed. One needle was inserted through each of 10 holes of the template, and variations in the probe rotation angles for detecting the needle were measured. Results  The mean variation of probe rotation for detecting a single needle was 17.0° (range 4°–25°). Slightly broader variation was seen for the needle in holes farther away from the probe. Conclusion  Probe rotation angles for detecting a single needle displayed considerable variation. Seed locations recognized on sagittal imaging by TRUS are thus indeterminate, and real-time dose calculations using TRUS for 125I seed implantation should be used with care.  相似文献   
38.
We evaluated a 39-year-old pregnant woman with right temporal lobe epilepsy. During the second trimester, seizure deterioration was responsive to an increased daily dose of levetiracetam (LEV). However, immediately after delivery, new non-habitual seizures emerged along with a sharply increased LEV concentration. The frequency of habitual seizures also slightly increased. The non-habitual seizures completely disappeared, and the frequency of the habitual seizures improved to the baseline level after the LEV dosage was reduced. Thus, a paradoxical effect of an increased LEV blood concentration was assumed to be a potential cause of these events. Peripartum pharmacokinetic fluctuations in LEV levels should be monitored carefully.  相似文献   
39.
SUMMARY BACKGROUND DATA: Quick intraoperative parathyroid hormone assays are widely used as a guide to the adequacy of resection during parathyroid surgery. However, some authors have reported a 15% error rate of these assays because of the presence of false-positive and false-negative results. Recently the authors have found that most commercial intact PTH (iPTH) assays cross-react with non-(1-84) PTH (likely 7-84 PTH) and that the proportional levels of non-(1-84) PTH in patients were variable in a much wider range, accounting mostly for 20% to 60% of the immunoreactivity in samples obtained from hyperparathyroid patients. A cyclase activating PTH (CAP) measured by a novel immunoradiometric assay was shown to measure specifically 1-84 PTH. Using a CAP assay, the authors studied the rate of decline of CAP after parathyroidectomy and compared it with iPTH as measured by the Nichols intact PTH immunoradiometric assay. METHODS: This study comprised 29 patients with primary hyperparathyroidism (pHPT) caused by a single adenoma and 7 patients with secondary hyperparathyroidism (secondary HPT) who underwent parathyroidectomy. Blood samples were drawn after anesthesia, before excision of one enlarged parathyroid gland in pHPT and of the last gland in secondary HPT, and at 5, 10, and 15 minutes after excision. The 7-84 PTH level was calculated by subtracting the CAP value from the iPTH value. RESULTS: The percentage of 7-84 PTH in iPTH in plasma samples was 27.5 +/- 14.4% in pHPT and 39.6 +/- 15.1% in secondary HPT. In pHPT patients the plasma CAP and iPTH value decreased to 23.4 +/- 10.8 and 32.0 +/- 11.3% of the preexcision level at 5 minutes, 10.6 +/- 7.7 and 21.1 +/- 8.8% at 10 minutes, and 8.5 +/- 4.9 and 16.1 +/- 6.8% at 15 minutes after removal of the enlarged gland, respectively. At 5 minutes, CAP levels of all 29 pHPT patients had decreased to less than 40% of the preparathyroidectomy level; however, 7 (24%) patients still had an iPTH level of more than 40%. In secondary HPT patients, CAP and iPTH values had dropped to 43.3 +/- 20.2 and 66.1 +/- 19.7% at 5 minutes, 28.6 +/- 16.6 and 53.6 +/- 18.1% at 10 minutes, and 14.2 +/- 9.0 and 41.0 +/- 12.9% at 15 minutes after removal of the last enlarged gland, respectively. At 10 minutes, CAP levels of all seven secondary HPT patients had decreased to less than 50% of the preexcision level; however, three (43%) patients still had an iPTH level of more than 50%. In pHPT and secondary HPT, the 7-84 PTH level had dropped to 57.4 +/- 85.9 and 62.1 +/- 84.9%, respectively, of the preexcision value 15 minutes after removal of the enlarged gland or glands. CONCLUSIONS: The percentage of 7-84 PTH in iPTH in plasma samples varies substantially between patients with HPT. In both pHPT and secondary HPT, the plasma CAP value decreased more rapidly than iPTH after parathyroidectomy, depending on the amount of 7-84 PTH in circulation. These results suggest that the CAP assay may be a more useful adjunct to parathyroidectomy than the currently used iPTH assay.  相似文献   
40.
We report a case of bilateral internal carotid artery (ICA) stenosis treated with stenting. A 78-year-old man suffered from vascular dementia and left hemiparesis, and, by magnetic resonance angiogram (MRA), was diagnosed as having bilateral ICA stenosis. Cerebral angiogram showed severe, bilateral ICA stenosis (right; 88%, left; 93%) and xenon single photon emission tomography (SPECT) showed severely decreased cerebral blood flow (CBF) and cerebrovascular reactivity (CVR). We performed bilateral carotid angioplasty with self-expanding stents. Both CBF and CVR were improved bilaterally after the operation. The patient was discharged without neurological deficits. Carotid stenting may be an alternative treatment for severe ischemia caused by severe, bilateral ICA stenosis.  相似文献   
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