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41.
The relationship between the numerical aberrations of chromosome 7 in interphase cells and the clinicopathological behavior of breast tumors was investigated in 51 touch imprinted preparations of breast tumors. Using fluorescence in situ hybridization with a chromosome 7-specific DNA probe, the fluoresceinisothiocyanate (FITC) spots mean and the representative copy number of each breast tumor were examined. The FITC spots mean (2.34) of 40 breast cancers increased compared with that of 11 benign lesions (1.98) (P < 0.02). The FITC spots mean tended to increase with the advancing stage and tumor size of the breast cancer. The FITC spots mean in the case with metastasis was also of a higher value than that without metastasis (P < 0.01). Furthermore, the existence of trisomy or over-trisomy of the copy number was related to the advancing stage and tumor size (P < 0.05 and P < 0.01, respectively). These findings suggest that the FITC spots mean and polysomy of the number of chromosome 7 may be highly predictive for breast tumor aggressiveness.  相似文献   
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The mesophase induced circular dichroism (CD) of biphenyl and its derivatives was investigated using the Tween 80 (monooleate of the ether of sorbitan with 4 mol of polyethyleneglycol)-water system, which can form a twisted smectic mesophase. The sign of CD bands in this mesophase is explained by a modified C2-symmetry rule, since it can be considered that alignment of the solute molecules in this mesophase can be elucidated in terms of a pseudo-C2 symmetry, when the concentration of the solute is comparatively high. The assignments of the electronic transitions of the solute molecules show a good accordance with results of magnetic circular dichroism study.  相似文献   
44.
An 18-year-old woman with abdominal pain was diagnosed as having splenic cysts by computed tomography scan. She had high serum levels of CA19-9 (2886.8 U/mL; normal value, <35 U/mL), CA125 (131.1 U/mL; normal value, <35 U/mL) and soluble IL-2 receptor (1490 U/mL; normal range, 220-530 U/mL). The resected spleen weighed 1050 g, was 14 x 28 cm, and had more than 10 macroscopic cysts up to 10.3 x 9.5 cm. There were numerous microscopic cysts in the spleen and several on the splenic capsule. The levels of CA19-9 and CA125 in the cyst fluid were 2165550 U/mL and 160400 U/mL, respectively. After the surgery, the serum levels of the tumor markers decreased gradually. The inside of the largest cyst was mainly covered by granulation tissue with a focal lining of epithelial cells, and the other macroscopic cysts had stratified squamous epithelium. The microscopic splenic cysts and cysts on the splenic capsule were lined by either attenuated single-layered or multilayered epithelial cells. The lining epithelial cells of these cysts were positive for epithelial membrane antigen and cytokeratins. CA19-9 and CA125 were detected in the lining cells of the splenic cysts. In the present case, it is suspected that the splenic cysts were derived from the capsular lining cells that showed migration from the capsule or formed microcysts on the splenic capsule, as in the case of ovarian inclusion cysts.  相似文献   
45.
We investigated the aberrant promoter hypermethylation of p16, p15 and p14 genes and loss of heterozygosity (LOH) at 9p21-22 in 48 cases of adenocarcinoma of the lung. The frequencies of hypermethylation of genes were as follows: p16, 25.0%; p15, 22.9%; and p14, 18.8%. The frequency of LOH at chromosome 9p21-22 was 60.9%. The frequency of two-hit inactivation of the p16 gene by hypermethylation and LOH was 21.7%. Two-hit inactivation of the p16 gene showed loss of protein expression and was significantly correlated with tumor size, tumor grade and the Ki-67 labeling index. Hypermethylation of the p16 gene was not significantly correlated with hypermethylation of the p15 and p14 genes, both of which are close to the p16 gene locus, suggesting that hypermethylation of these genes occurs selectivity. In conclusion, biallelic inactivation of the p16 gene by hypermethylation and LOH might cause loss of p16 expression and play an important role in the development of adenocarcinoma of the lung. Therefore, controlling and monitoring for hypermethylation of the p16 gene may be partially useful for treatment and early diagnosis of adenocarcinoma of the lung.  相似文献   
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In vitro corrosion fatigue of 316L cold worked stainless steel.   总被引:2,自引:0,他引:2  
The corrosion resistance of 316L cold worked stainless steel depends upon its thin protective oxide layer; and if this is partially broken down, corrosion resistance depends upon its tendency for repassivation. Since the intended function of stainless-steel implants is to sustain musculoskeletal forces, research toward the stability of the oxide film during dynamic loading in simulated bodylike fluids is warranted. A pilot corrosion fatigue study was, therefore, performed on uniaxial tension fatigue specimens cycled to various maximum stress levels near their yield point while immersed in 37 degrees C isotonic saline solution, and combined with the electrochemical insult of (a) imparting an 800 mV vs. SCE anodic potential for 20 s to stimulate local film breakdown, and then (b) returning to a constant 200 mV vs. SCE anodic potential and maintaining that potential during cyclic loading until the specimens broke in two. During the anodic polarization by continuously monitoring the current it was possible to (a) observe the repassivation and corrosion behavior following stimulation, and (b) detect crack initiation, crack propagation and failure onset. The combined effects of accelerated corrosion and mechanical fatiguing disturbed the repassivation tendency and reduced the crack initiation times and the fatigue lives as compared to air and saline controls. As the maximum cyclic load levels were increased, the fatigue lives were further foreshortened.  相似文献   
48.
CT-guided stereotactic brachytherapy has been performed for the deep-seated malignant gliomas using the double-catheter after-loading method. The catheter system consists of two coaxial polyethylene tubes with closed tips. The outer catheter is 3.0 mm in outer diameter and 2.4 mm in inner diameter. The inner catheter is 2.0 mm in outside diameter and 1.4 mm in inside diameter, and contains the radioactive sources. Localization of the target volume is determined by the preoperative findings of computed tomography (CT), magnetic resonance imaging (MRI), and cerebral angiography. Dosimetry and dose planning are so finalized for the target volume as to be irradiated interstitially more than tumoricidal dose. After stereotactic biopsy of the deep-seated brain tumors, stereotactic implantation of the outer catheters is performed using Iseki Stereotactic System in the CT room. Burr holes had been previously opened in the operating room. The inner catheters containing nonradioactive sources (dummy sources) are inserted, and skull X-p is taken to confirm the position of the dummy sources, and to calculate the dosimetry by computer. The inner catheters are replaced with catheters containing radioactive sources (226Ra) in the irradiation room. 226Ra sources deliver at least 500 rads/day (approximately 20 rads/hr) to the target volume as interstitial irradiation. Two patients of malignant gliomas treated with this procedure were shown as representative cases. These patients underwent CT-guided stereotactic brachytherapy as "boost" combined with conventional external irradiation.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
49.
Positron computed tomography (PCT) was performed in 3 normal volunteers and 21 patients with cerebrovascular diseases using a high resolution PCT device Positologica-I and three tracers11CO,13NH3, and18FDG. Relatively early lesions showed various accumulation patterns, and metabolism and perfusion mismatches were clearly shown by this measurement. One type of mismatch is luxury perfusion which had a slight increase of blood volume. Another type of uncoupling is misery perfusion. Remote effects of ischemic lesions also appeared on PCT with18FDG and13NH3. From our clinical results, the PCT method with a high resolution device and radiopharmaceuticals such as11CO,13NH3, and18FDG is very useful in the assessment of cerebrovascular diseases and in defining circulatory dysfunction in man.  相似文献   
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