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31.
Sodium valproate was administered to Jcl:ICR mice in order to evaluate teratogenicity in the cardiovascular system. A single dose of 600mg/kg of sodium valproate was injected intraperitoneally on gestational day 6, 7, 8 or 9. On day 18 of gestation, dams were laparotomized to observe incidence and type of cardiovascular abnormality in live fetuses. Cardiovascular abnormalities were found most frequently in the group treated on day 7, being recognized in 86% of litters (19/22) and in 29% of live fetuses (70/238). Among these, there were 28 cases of transposition of the great arteries, 13 of double outlet right ventricle, 11 of endocardial cushion defect, 9 of ventricular septal defect, 5 of tricuspid atresia, and 4 of hypoplastic left heart syndrome.  相似文献   
32.
RATIONALE AND OBJECTIVES. The sialographic ductal patterns of the parotid glands in patients with Sj?gren syndrome were compared with those of normal patients by measuring the fractal dimensions. METHODS. Fractal dimensions were estimated using the modified pixel dilation method. RESULTS. The mean fractal dimension was 1.64 +/- 0.06 for the normal glands and 1.39 +/- 0.10 for the glands with Sj?gren syndrome (P < .005). No correlation between the age or sex and fractal dimension was observed for both groups. In Sj?gren syndrome, a significant difference in the fractal dimension was observed between the subgroup having punctuate fillings with a diameter less than 1 mm and the subgroup from 1 to 2 mm (P < .001). CONCLUSION. The fractal dimension is useful as a numeric grading of the complexity of the ductal pattern and the progression of parotid disease.  相似文献   
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34.
We report a case of an anterior interosseous nerve palsy after closed reduction and percutaneous pinning of open fractures of the radius and ulna in an adult. Operative findings showed that the anterior interosseous nerve was trapped between the distal and proximal part of the fractured radius. Treatment by neurorrhaphy gave a satisfactory result.  相似文献   
35.
Recently, a self‐expandable metallic stent has been recognized for treatment of malignant duodenal stenosis. But the complications by stenting are important problems even now. In the present study, we report our new method of duodenal stenting by using of double‐balloon enteroscopy considered safe and effective.  相似文献   
36.
We report the case of a 67-year-old woman with severe hypertension caused by an extra-adrenal pheochromocytoma. The tumor was detected by 131I metaiodobenzylguanidine scintigraphy and it was found to be small (2 cm ?) by enhanced CT. After the extirpation of the tumor, the blood pressure of the patient immediately normalized. It should be taken into account that a small extra-adrenal pheochromocytoma can be one of the causes of secondary hypertension in elderly patients. Since small extra-adrenal pheochromocytomas are difficult to detect, it is also important to perform suitable examinations to establish the diagnosis. Furthermore, we emphasize the importance of an accurate diagnosis in elderly patients with pheochromocytoma, for they often have less symptomatology and more severe cardiovascular complications due to refractory hypertension than younger patients.  相似文献   
37.
1. Intrarenal arterial infusion of hypertonic saline (HS) transiently increased and then gradually reduced renal blood flow (RBF) in anaesthetized dogs. Glomerular filtration rate (GFR) but not filtration fraction decreased at the end of the infusion. 2. In the presence of a potassium channel opener cromakalim (0.3 μg/kg per min), HS infusion failed to reduce RBF; the initial increase in RBF was maintained throughout the infusion. Since cromakalim also prevented the decrease in GFR, HS infusion lowered filtration fraction. 3. The results suggest that cromakalim inhibits both pre-and postglomerular vasoconstriction induced by HS infusion.  相似文献   
38.
39.
Alveolar bone resorption by osteoclasts is essential for tooth eruption. Osteoclast-deficient Csfm(op) homozygous (op/op) mice, which lack functional macrophage colony-stimulating factor (M-CSF), suffer from osteopetrosis and completely lack tooth eruption. Although osteoclasts appear, and osteopetrosis is cured with age in op/op mice, tooth eruption is never seen. This fact suggests that there is a critical period when osteoclasts are required for tooth eruption. In this study, to detect the critical period, we administered an antagonistic antibody directed against c-Fms, a receptor for M-CSF, to inbred C57BL/6 mice for various periods. Administration of this antibody decreased tartrate-resistant acid phosphatase-positive (TRAP) osteoclasts, and incisor eruption was completely inhibited by continual administration of this antibody from embryonic day 15.5 (E15.5) until postnatal day 12.5 (D12.5). A 1-day delay of this administration abolished the inhibition of incisor eruption. The number of TRAP-positive osteoclasts was significantly reduced between E16.5 and E18.5 in the mice treated with antibody from E15.5 compared with those treated from E16.5. These results indicate that this period, during which the number of osteoclasts decreases significantly, is critical for inhibiting incisor eruption in C57BL/6 mice.  相似文献   
40.
BACKGROUND: To clarify the possible role of nitric oxide (NO) and stress proteins in oncogenesis and cytodifferentiation of odontogenic epithelium. Inducible NO synthase (iNOS) and heat shock proteins (HSPs) were analyzed in ameloblastomas as well as in tooth germs. METHODS: Specimens of seven tooth germs, 36 benign ameloblastomas and five malignant ameloblastomas were examined by immunohistochemistry using antibodies against iNOS and 27-, 60- and 70-kDa HSPs (HSP27, HSP60 and HSP70). RESULTS: Immunoreactivity for iNOS was detected in normal and neoplastic odontogenic epithelial cells and was higher in malignant ameloblastomas than in tooth germs and benign ameloblastomas. HSP27 was expressed constitutively in all odontogenic epithelial cells in tooth germs and benign and malignant ameloblastomas. Expression of HSP60 and HSP70 was detected in normal and neoplastic odontogenic epithelial cells and was prominent in cells neighboring the basement membrane. HSP60 reactivity showed no apparent difference between normal and neoplastic odontogenic epithelium, whereas HSP70 expression was slightly higher in benign and malignant ameloblastomas than in tooth germs. CONCLUSIONS: Activation of iNOS might be associated with malignant potential of epithelial odontogenic tumors. Elevated expression of HSP70 is considered to be involved in neoplastic transformation of odontogenic epithelial cells.  相似文献   
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