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81.
82.
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   
83.
A rapid method for detecting barbiturates in serum using EI-SIM   总被引:2,自引:0,他引:2  
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   
84.
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   
85.
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   
86.
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   
87.
88.
Bropirimine [2-amino-5-bromo-6-phenyl-4-(3H)-pyrimidinone] is a low-molecular-weight compound that acts as an inducer of interferon in several animal species. Experiments were designed to explore the possibility of using this drug for the treatment of renal-cell carcinoma (RCC). Euthymic BALB/c mice were inoculated with murine RCC (Renca) cells and given graded doses of Bropirimine p.o. for 5 consecutive days beginning on day 1 following tumor inoculation. These mice were killed and tumors were excised on day 21. Bropirimine significantly (P<0.01) inhibited the tumor growth at a daily dose of 1,000 or 2,000 mg/kg. No adverse effect or toxicity was noted at 1,000 mg/kg, and at 2,000 mg/kg there was only a marginal body-weight reduction without any other appreciable side effect. In addition to the inhibition of tumor growth, there was a small yet significant (P<0.05) increase in the duration of survival (in days) in the Bropirimine-treated animals. When the treatment was delayed to begin on day 6 following tumor inoculation, Bropirimine did not suppress tumor growth in euthymic mice, pointing to the importance of the timing of the treatment. In athymic nude BALB/c mice lacking T-cells or T-cell function, Bropirimine also inhibited tumor growth (P<0.01). The antitumor effect of this drug was abolished by pretreatment with anti-asialo GM1 serum, which eliminated natural killer (NK) activity in euthymic mice. In vivo treatment with Bropirimine augmented the cytotoxicity of lymphocytes isolated from the spleens or lungs of the tumor-bearing mice, which were active against Renca and YAC-1 cells in vitro. This activity was NK-cell-dependent as judged on the basis of the results of the in vitro complement-dependent cytotoxicity assay. Since Bropirimine induced interferon (IFN)-/ production, significantly (P<0.05) elevating its serum concentration, and since this drug mimics the effects of IFN-/, it seemed likely that the Bropirimine-induced NK cell augmentation we found was mediated by IFN-/. These results suggest that Bropirimine, a booster of NK activity, may have potential as an adjunct to other therapeutic modalities in the treatment of human RCC.  相似文献   
89.
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   
90.
To investigate the adequate extent of esophagectomy and lymphadenectomy for an esophageal cancer localized at the cervicothoracic junction, the mortality and morbidity rates, survival rates, and patterns of recurrence were retrospectively analyzed in two groups—14 patients who underwent total esophagectomy with or without laryngectomy and 15 patients who underwent proximal esophagectomy with or without laryngectomy—at Kurume University Hospital from 1981 to 1996. Proximal esophagectomy with or without laryngectomy resulted in a lower hospital mortality rate and better overall survival for patients who underwent curative esophagectomy compared with total esophagectomy with or without laryngectomy. Multivariate analysis indicated that the extent of esophagectomy (total esophagectomy versus proximal esophagectomy) was not a prognostic factor. The incidence of recurrence was not different between the two groups. Lymph node metastasis or recurrence from such esophageal cancers was localized to the neck and upper mediastinum. For an esophageal cancer localized at the cervicothoracic junction, therefore, proximal esophagectomy with or without laryngectomy and with cervical and upper mediastinal lymphadenectomy could be better indicated for preselected patients.  相似文献   
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