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101.
The purposes of this study were to establish normative data for mesiodistal tooth crown diameters and arch dimensions in Mongolian adults and to compare them with those of Japanese adults. The study materials comprised dental casts of 100 modern Mongolian and 100 Japanese subjects (50 males, 50 females for each) with Angle Class I normal occlusion. The mean ages were 20 years 8 months for the Mongolian subjects and 20 years 0 months for the Japanese subjects. On the dental casts, the mesiodistal tooth crown diameters (excluding wisdom teeth) and dental arch dimensions were measured. The following arch dimensions were measured: inter-canine lingual, inter-premolar lingual, inter-molar lingual, inter-molar central, coronal arch length, basal arch length, and basal arch width. In the Mongolian samples, significant sex differences were noted, and most of the items were significantly larger in males than in females. Significant differences between the Mongolian and Japanese samples were mainly noted in the premolar and molar regions, rather than in the anterior region, and were significantly smaller in the Mongolian samples. In the Mongolian samples, the molar section widths and basal arch width and length were significantly larger in males and females compared with the Japanese samples. These results suggest that the tooth crown size and arch dimensions in the Mongolian samples differed from those in the Japanese samples, and that establishment of the clinical norm for Mongolian adults might be helpful in formulating treatment plans for Mongolian patients, given that these parameters are the basic tools for diagnosis.  相似文献   
102.
This study was undertaken to evaluate the effectiveness of radical lymphadenectomy in ampullary cancer with nodal disease. Thirty-five patients underwent the Whipple procedure with radical lymphadenectomy. The location and number of positive nodes was characterized. Eighteen patients (51%) had positive nodes. Patients without nodal disease (pNO group) had an actuarial 5-year survival rate of 81%. Seven patients with metastasis confined to the pancreaticoduodenal nodes had a 5-year survival rate of 67%, which was comparable to the pNO group (N.S.) and better than the 27% 5-year survival rate in patients with positive superior mesenteric nodes (P < 0.05). Eleven patients with one to three positive nodes had a 5-year survival rate of 71%, which was also comparable to the pNO group (N.S.) and better than the 0% 5-year survival rate in patients with four or more positive nodes (P < 0.01). Radical lymphadenectomy is effective against a limited degree of nodal disease. © 1996 Wiley-Liss, Inc.  相似文献   
103.
Imatinib mesylate inhibits signaling of tyrosine kinase receptors, including PDGFRα, and has been used for human cancer therapy. Recent studies have indicated that imatinib is also effective in treatment of some chronic diseases with fibrosis. Fibrosis is the feature of Duchenne muscular dystrophy. It has been reported that imatinib attenuates fibrosis in mdx mice. Recently we revealed that PDGFRα is specifically expressed in muscle mesenchymal progenitors, which are the origin of muscle fibrosis. Here, we show that imatinib ameliorates the muscular pathology of DBA/2-mdx, a more severe mouse muscular dystrophy. In addition, imatinib inhibits both the proliferation and fibrosis marker expression induced by PDGF-AA in muscle mesenchymal progenitors in vitro. Importantly, the effective dose of imatinib on muscle mesenchymal progenitors did not inhibit myoblast proliferation. These results suggest that imatinib targets mesenchymal progenitors, and that a therapeutic strategy targeting mesenchymal progenitors could be a potential treatment for muscular dystrophies.  相似文献   
104.
105.
The condition of experimental allergic encephalomyelitis (EAE) induction was investigated in several mice strains. SJL and C3H/He strains were found to be susceptible. A single immunization with mouse spinal cord, complete Freund's adjuvant (CFA) and pertussis vaccine produced clinical signs of EAE in SJL and C3H/He strains after 11 to 18 days. Isogenic spinal cord produced EAE in C3H/He strain. A single immunization with myelin basic protein from bovine spinal cord in CFA and pertussis vaccine produced EAE in SJL strain. EAE susceptibility of SJL strain correlated with the amount of mycobacteria used for sensitization. It was necessary to give pertussis vaccine intravenously in all cases.  相似文献   
106.
This study concerns the histologic examination of apatite-titanium complex dental implants (two-piece, cylindrical type) in dogs. There was no plaque control. One to 3 months after implantation, the surface of the apatite root was directly bound to newly formed, woven bone. Seven-and-a-half months to 1 year after implantation, the apatite root was directly bound to the newly formed lamellar bone, which provided strong bone bonding (apatite-bone bonding). There appear to be two types of mechanisms for the resorption of apatite ceramics: first, cellular-type resorption by both multinuclear and mononuclear macrophages; and second, a noncellular, fluid mechanism (dissolution). The gingival sulcus around implants and downward growth of the epithelial cells could be observed in almost all of the implants. There was no cellular inflammation in the tissue around the implants, in the nasal cavity, or in the maxillary sinus. From this study we concluded that clinical application of this dental implant system would be practical.  相似文献   
107.
Thyroid masses are a common clinical finding, and their management remains controversial. The purpose of this study was to evaluate the clinical effect of performing routine ultrasound (US) examinations and US-guided fine-needle aspiration biopsy (US-FNAB) in the management of diffuse or nodular goiter diagnosed by mass screening. Mass screening carried out from 1993 to 1996 revealed 444 women with goiter, 322 of whom had diffuse goiter and 122 had nodular goiter. All of these patients underwent US examination, the results of which determined that 169 should undergo US-FNAB to confirm an accurate diagnosis of their thyroid tumors. Histological examinations after surgical resection revealed that 12 of the 322 patients with diffuse goiter (3.7%) and 23 of the 122 with nodular goiter (18.9%) had malignant tumors. Among the 61 thyroid tumors surgically verified, US-FNAB yielded a sensitivity rate of 93%, a specificity rate of 81%, and an accuracy rate of 90%. Insufficient aspiration was obtained from 5%. Performing US-FNAB-resulted in an elevation in the percentage of malignant tumors yielded at surgery of up to 72%. Thus, ultrasonography followed by US-guided-FNAB could be a useful routine method of evaluating thyroid tumors detected by mass screening. Moreover, a greater number of unnecessary thyroid operations can be avoided by performing US-FNAB rather than FNAB alone.  相似文献   
108.
Summary We report the color Doppler ultrasonography features of arteriovenous malformation (AVM) of the pancreas, a very rare disease. The patient was a 52-year-old man with congenital AVM of the pancreas and a duodenal ulcer that had been resistant to medication. Endoscopic color Doppler ultrasonography (color Doppler EUS) revealed many abnormal color signals showing pulsatile wave form at the portion of the duodenal wall involving the duodenal ulcer. Extracorporeal color Doppler ultrasonography revealed a mosaic-like color signal, caused by turbulent flow, in the portal trunk. Angiography demonstrated a vascular network with extensive proliferation at the pancreatic head and early portal filling. It is possible that the pancreatic AVM had caused the duodenal ulcer. Color Doppler EUS can be a useful modality for detection of vessel abnormalities of the gastrointestinal tract.  相似文献   
109.
Recent research progress indicates a close link between ghrelin, a natural ligand of GH secretagogues receptor (GHS-R), and both the metabolic balance and body composition. To clarify the involvement of ghrelin and GHS-R in the process of adipogenesis, we measured the expression of GHS-R and peroxisome proliferator-activated receptor gamma 2 (PPAR-gamma 2) mRNA in rat adipocytes using semiquantitative RT-PCR methods. The levels of GHS-R mRNA increased by up to 4-fold in adipose tissue from epididymal and parametrial regions as the rat aged from 4-20 wk and were significantly elevated during the differentiation of preadipocytes in vitro. Ghrelin (10(-8) M for 10 d) stimulated the activity of glycerol-3-phosphate dehydrogenase and the differentiation of rat preadipocytes in vitro. Ghrelin treatment also significantly increased the levels of PPAR-gamma 2 mRNA in primary cultured rat differentiated adipocytes. In addition, isoproterenol (10(-8) M, 40 min)-stimulated lipolysis was significantly reduced by simultaneous ghrelin treatment in a dose-dependent manner in vitro. In conclusion, the expression of GHS-R in rat adipocytes increases with the age and during adipogenesis. Ghrelin in vitro stimulates the differentiation of preadipocytes and antagonizes lipolysis. Ghrelin may therefore play an important role in the process of adipogenesis in rats.  相似文献   
110.
1.?CS-0777, a candidate compound for autoimmune diseases, becomes phosphorylated active metabolite, M1, by fructosamine 3-kinase (FN3K), FN3K-related protein (FN3K-RP); and M1 is reverted back to CS-0777 by alkaline phosphatase (ALP) in the body. We performed enzyme kinetic analysis of phosphorylation of CS-0777 by FN3K, FN3K-RP, human erythrocytes and human platelets; and dephosphorylation of M1 by various ALP isozymes and human liver, kidney, lung and small intestine microsomes.

2.?The Michaelis constants of human FN3K, FN3K-RP and erythrocytes for CS-0777 phosphorylation were in the range from 498?μM to 1060?μM. FN3K inhibitor, 1-deoxy-1-morpholinofructose, suppressed only about 20% of CS-0777 phosphorylation activity in human erythrocyte lysate. Immunodepletion of FN3K and FN3K-RP decreased M1 formation activity by about 25% and 50%, respectively, in human erythrocyte lysate.

3.?The Michaelis constants of four human ALPs and microsomes were in the range from 10.9?μM to 32.1?μM. The ALP inhibitor, levamisole, suppressed over 50% of M1 dephosphorylation activity in liver, kidney and lung microsomes.

4.?FN3K-RP is expected to take a prominent role in the phosphorylation of CS-0777 in human erythrocytes; dephosphorylation of M1 was observed in all ALPs and human tissue microsomes examined, with a similar affinity towards M1 among them.  相似文献   
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