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71.
A calcia base investment has high stability even with melted titanium and, therefore, can produce an excellent titanium casting. In this study, titanium powder was distributed to a calcia base investment as an expanding agent, and the firing temperature of the mold was controlled at 800 degrees C. The calcia base investment with 6.1% wt titanium powder expanded 1.7% during 2 h heating at 800 degrees C. The marginal discrepancies between the die and the titanium crown were improved by the addition of the titanium powder to the investment. The mean thickness of the cement layer between the epoxy teeth and the crown using 6.1% wt titanium powder content was from 40-80 microns. 相似文献
72.
A rapid method for detecting barbiturates in serum using EI-SIM 总被引:2,自引:0,他引:2
T. Kojima T. Taniguchi M. Yashiki T. Miyazaki Y. Iwasaki T. Mikami M. Ohtani 《International journal of legal medicine》1994,107(1):21-24
A simple and rapid method for analysis of barbiturates in serum has been developed. In order to extract and clean barbiturates in serum, a separation column packed with Extrelut and Florisil was used, and the eluate was directly analyzed by means of electron impact selected ion monitoring (EI-SIM). Selected ions used were base peak ions of 10 barbituartes, and the internal standard used was allobarbital or secobarbital. The calibration curves were linear over the range 0.5–5 ng. Extraction of replicate serum samples containing 20 g/1.5 ml and 5 g/1.5 ml resulted in a recovery of 87.2–105.2% and 81.6–104.6%, respectively, with the exception of phenobarbital, which was 151.9% and 172.1%, respectively. Secobarbital was also analyzed in the serum of 13 patients who had been given secobarbital intravenously. In 3 out of 10 cases, Secobarbital levels greater than 1 g/ml were detected more than 72 h after administration. This method seems to have possibilities for clinical use.Paper presented at the 2nd International Symposium ADVANCES IN LEGAL MEDICINE, Berlin, Germany, August 30–September 1, 1993 相似文献
73.
Noguchi M Kitagawa H Michael T Kinoshita K Earashi M Miyazaki I Mizukami W 《Oncology reports》1994,1(1):133-138
We analyzed association between p53 and/or Rb expression and clinicopathologic variables or Ag-NOR counts, and then ascertained whether p53 and/or Rb expression would be useful for estimating prognosis in 81 breast cancer patients. Positive p53 expression was significantly associated with post-menopausal status, axillary lymph node metastases and Ag-NOR counts, whereas low level Rb expression was significantly associated with tumor size. Moreover, the combination of p53 and Rb expression was significantly associated with Ag-NOR counts, although there was no significant association between p53 and Rb expression. In the univariate study, p53 expression as well as age and axillary lymph node metastases were significantly associated with survival, whereas Rb expression was not. In the multivariate study, p53 and/or Rb expression did not provide independent prognostic information, although axillary lymph node metastases was an important factor affecting survival. Our findings suggest that p53 and/or Rb expression may reflect tumor proliferation of breast cancer, but the prognostic value of such assays is limited. 相似文献
74.
Ohta T Terada T Nagakawa T Kayahara M Nishimura G Tsukioka Y Taniguchi K Miyazaki I Numata M Yamamoto M Iseki S Kanno M 《Oncology reports》1994,1(4):759-764
Pancreatic trypsinogen expression in 149 surgically resected extrapancreatic gastrointestinal neoplasms was evaluated immunohistochemically. Immunohistochemistry was performed using a monoclonal antibody against human pancreatic trypsinogen. Pancreatic trypsinogen expression was detected in 28 of 55 gastric carcinomas (50.9%), 22 of 44 colorectal cancers (50%), 12 of 20 gallbladder cancers (60%), nine of 10 extrahepatic bile duct cancers (90%), and none of 20 hepatocellular carcinomas. The intensity of immunoreactivity in the tumor area varied from specimen to specimen, and from area to area within the same specimen. In most cases, however, immunoreactivity was more pronounced at the infiltrative margin of the tumor. Additionally, the highly differentiated carcinoma cells tended to display a focal, fine granular immunoreactive pattern, usually present in the supranuclear cytoplasm, while the poorly differentiated carcinoma cells displayed a fine granular pattern, usually present over the entire cytoplasm. These findings suggest that some extrapancreatic gastrointestinal neoplasms express pancreatic trypsinogen immunoreactive peptides, raising the possibility that secreted pancreatic trypsinogen plays a role in carcinoma invasion and metastasis, as has been shown for other classes of proteases. 相似文献
75.
Noguchi M Earashi M Ohnishi I Kinoshita K Thomas M Fusida S Miyazaki I Mizukami Y 《International journal of oncology》1994,4(6):1353-1358
The relationship between nm23 expression, HPA staining, and other clinicopathological variables, i.e., axillary (AX) and internal mammary lymph node (IMN) metastases was assessed, and their prognostic values were analyzed. Positive HPA staining was found to be significantly correlated with tumor size, and with AX and IMN metastases, whereas negative nm23 expression was significantly correlated with AX and IMN metastases. A univariate study revealed that overall survival was correlated significantly with tumor size, AX and IMN metastases, and HPA staining, whereas nm23 expression did not appear to be a significant prognostic factor. In a multivariate study, only AX and IMN metastases were significant prognostic factors. When AX and IMN metastases were excluded from the Cox model, however, only HPA staining had independent prognostic value for survival. In this study, therefore, it may be concluded that HPA staining was more closely correlated with AX and IMN metastases, and with survival than nm23 expression. 相似文献
76.
Although breast conserving treatment (BCT) has become the standard therapy for early breast cancer, breast removal is still
recommended for patients with a tumor beneath the nipple or with Paget’s disease. We have employed transposition of a latissimus
dorsi myocutaneous (LD-MC) flap after wide local excision of a tumor with the nipple-areola complex. A new nipple-areola complex
was reconstructed on the LD-MC flap after breast irradiation. Utilizing reconstructive techniques, BCT will likely become
the treatment of choice for more patients with early breast cancer. 相似文献
77.
T. Yamada K. Miyazaki N. Koshikawa M. Takahashi H. Akatsu T. Yamamoto 《Acta neuropathologica》1995,89(3):199-203
Gelatinase A is an enzyme capable of cleaving soluble -amyloid protein (AP), and may function as an -secretase to produce secretory forms of amyloid precursor protein. We examined gelatinase A immunoreactivity in the brains and posterior roots of neurologically normal, lacunar stroke, Alzheimer disease (AD), amyotrophic lateral sclerosis, progressive supranuclear palsy and myasthenia gravis cases. The gelatinase A antibody stained only microglial cells in the white matter in all the brain tissues. In AD brain, the reactive microglia located in the center of classical senile plaques, as well as in other microglial cells in the gray matter, showed no immunoreactivity. Gelatinase A in white matter microglial cells may play a role in preventing local deposition of AP. In the posterior root, Schwann cells had positive immunoreactivity. As with other metalloproteases, gelatinase A in Schwann cells may play an antiproliferative role. 相似文献
78.
79.
Y Momose A Kaetsu T Ishii K Shibata M Miyazaki M Moriyama H Une 《Nihon eiseigaku zasshi. Japanese journal of hygiene》1999,54(2):474-480
Leptin, a product of the ob gene, is thought to play a key role in the regulation of adiposity. However, it is unclear in humans as to whether or not leptin influences the blood pressure, serum lipids, physical activity level, or eating behavior in relation to obesity. Recent reports have indicated both gender-based differences in the leptin levels and a correlation of the percentage of body fat with leptin levels has been observed among obese subjects. As far as we know, these relationships among non-obese young adults have yet to be studied. Therefore, the serum leptin concentrations among 107 non-obese students (72 males and 35 females) were measured by a radioimmunoassay(RIA). Fasting leptin levels ranging between 1.2 and 23.4 ng/mL were observed in all subjects, and the levels among females were 2.6 times higher than in males (7.64 vs 2.95 ng/mL; p < 0.001). A close correlation was observed regarding the log-transformed leptin levels with the percentage of body fat as determined by the bioelectrical impedance analysis method(r = 0.734, p < 0.001 in males and r = 0.579, p < 0.001 in females). In conclusion, these data thus suggest the serum leptin levels among non-obese students show significant gender-based differences while, in addition, the leptin levels also correlate positively with the percentage of body fat. However, it remains unclear as to whether or not the leptin levels are independently related to the blood pressure, serum lipids, physical activity level (sports activity and leisure-time activity), and eating behavior (eating breakfast, mid-day snacking and nighttime snacking). 相似文献
80.
The renal lesions that develop in neonatal mice during angiotensin inhibition mimic obstructive nephropathy 总被引:3,自引:0,他引:3
BACKGROUND: Inhibition of angiotensin action, pharmacologically or genetically, during the neonatal period leads to renal anomalies involving hypoplastic papilla and dilated calyx. Recently, we documented that angiotensinogen (Agt -/-) or angiotensin type 1 receptor nullizygotes (Agtr1 -/-) do not develop renal pelvis nor ureteral peristaltic movement, both of which are essential for isolating the kidney from the high downstream ureteral pressure. We therefore examined whether these renal anomalies could be characterized as "obstructive" nephropathy. METHODS: Agtr1 -/- neonatal mice were compared with wild-type neonates, the latter subjected to surgical complete unilateral ureteral ligation (UUO), by analyzing morphometrical, immunohistochemical, and molecular indices. Agtr1 -/- mice were also subjected to a complete UUO and were compared with wild-type UUO mice by quantitative analysis. To assess the function of the urinary tract, baseline pelvic and ureteral pressures were measured. RESULTS: The structural anomalies were qualitatively indistinguishable between the Agtr1 -/- without surgical obstruction versus the wild type with complete UUO. Thus, in both kidneys, the calyx was enlarged, whereas the papilla was atrophic; tubulointerstitial cells underwent proliferation and also apoptosis. Both were also characterized by interstitial macrophage infiltration and fibrosis, and within the local lesion, transforming growth factor-beta 1, platelet-derived growth factor-A and insulin-like growth factor-1 were up-regulated, whereas epidermal growth factor was down-regulated. Moreover, quantitative differences that exist between mutant kidneys without surgical obstruction and wild-type kidneys with surgical UUO were abolished when both underwent the same complete surgical UUO. The hydraulic baseline pressure was always lower in the pelvis than that in the ureter in the wild type, whereas this pressure gradient was reversed in the mutant. CONCLUSION: The abnormal kidney structure that develops in neonates during angiotensin inhibition is attributed largely to "functional obstruction" of the urinary tract caused by the defective development of peristaltic machinery. 相似文献