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71.
A newly established cancer marker, the PFK inhibition test, has been further examined for its capacity to detect malignant neoplasms irrespective of the organs in which cancer cells start proliferating. We tested 1,160 sera from cancer patients and compared them with 756 normal sera, using histograms and normal paper for analysis of accumulated frequency. PFK activity through the influence of normal sera showed normal distribution, and cancerous sera shifted to the inhibitory site with an irregular shape. From these analyses, the patients were classified into the following types: normal range: PFK greater than SD (standard deviation of PFK activity in normal sera); suspicious range: SD greater than PFK greater than 2SD, must be given the PFK test again; and dangerous range: PFK less than 2SD, further examination must be carried out to detect cancer. Fifty percent of the sera from all the cancer patients inhibited PFK beyond 2 SD of normal sera. We also analyzed organ-associated PFK distribution, eg, gastric, colorectal, and mammary cancer. In gastric cancer, PFK inhibition was stronger in accordance with how far a particular stage of cancer had progressed. However, 50% of sera from stage I gastric cancer patients was positive beyond the cut-off line of 2 SD. We examined 104 sera from patients diagnosed as benign prostatic hypertrophy and found malignant cells in 10 patients whose sera tended to be positive in PFK inhibition. The PFK inhibitory factor in the body fluids of cancer patients was fractionated by Sephadex G-75 gel filtration and DEAE ion exchange chromatography. The approximate molecular weight of this factor was 13,000 daltons. The factor was resistant to heat and acid (0.1 N HCl and H2SO4) and was sensitive to 0.1 N NaOH and phosphate buffer. Diluted sulfuric acid and ammonium sulfate made an inactive NaOH-treated sample active when lyophilized following dialysis against distilled water. PFK inhibition by cancerous sera was eliminated by fructose-2,6-bisphosphate (the strongest activator of PFK) in a dose-dependent manner. PFK attached to agarose beads was found to be reversible even after being inhibited by cancerous body fluids and ATP water solution. Although PFK is apt to decay in a low pH range, the established procedure did not destroy PFK, but induced a direct inhibition of PFK by ATP through the ATP inhibition site on the PFK molecule. The PFK inhibitor may possibly function as a proton carrier and release protons to activate the ATP inhibition site.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
72.
73.
The derivatives (2) of 3-(2,3-dihydro-2,2-dimethyl-3-oxo-5-benzofuranyl) acrylic acid (2b) were synthesized. The compounds (3a-g) in which bromo, methoxy, nitro, amino or acetamido group was introduced on the benzene ring of the derivatives (2) and the compounds (3h-k) in which acryloyl moiety was introduced on the 6- or 7-position of the benzofuranone skeleton also synthesized. Furthermore, propionic acid derivatives (4a-c), acetic acid derivatives (4d-g), formic acid derivatives (4h-k) and oxyacetic acid derivatives (5) were prepared by converting the acryloyl moiety of the derivatives (2) into propionyl, acetyl, formyl and oxyacetyl groups. These compounds were tested for antiulcer activities. Among these compounds, 1-[3-(2,3-dihydro-2,2-dimethyl-3-oxo-5-benzofuranyl)acryloyl]piperidine (2d) and 4-[3-(2,3-dihydro-2,2-dimethyl-3-oxo-5-benzofuranyl)acryloyl] morpholine (2g) were found to have stronger antiulcer activities.  相似文献   
74.
75.
MR imaging in idiopathic portal hypertension   总被引:2,自引:0,他引:2  
Magnetic resonance imaging was performed in four patients with biopsy proven idiopathic portal hypertension (IPH). The MR images show proximity of medium-sized intrahepatic vessels to each other and to the liver surface in all patients. Small vessels running parallel to the second order branches of the intrahepatic portal vein are commonly seen as collateral pathways of portal flow in IPH and were seen in two patients. These findings were clearly demonstrated on gradient-recalled echo images. Intrahepatic periportal abnormal high intensity was seen in all patients on T2-weighted images and may reflect abnormalities in the portal tracts such as fibrous enlargement and increase in the number of vascular channels. Tiny low-intensity nodules sometimes observed in liver cirrhosis were not seen in any patient. Magnetic resonance was a useful noninvasive method in the differentiation of IPH from liver cirrhosis.  相似文献   
76.
Buoyancy and sedimentation of human X- and Y-bearing sperm   总被引:4,自引:0,他引:4  
The buoyant and sedimentation behaviors of human X- and Y-bearing sperm were examined in discontinuous density gradients of Nycodenz. The washed sperm placed at the bottom of the discontinuous density gradients of Nycodenz (23-50% in 3% steps) were centrifuged at 250 x g for various periods. The buoyant velocity of X-bearing sperm was faster than that of Y-bearing sperm. The sedimentation profiles of human sperm in the discontinuous density gradients of Nycodenz (4-20% in 2% steps) showed that X-bearing sperm sedimented faster than Y-bearing sperm. The separation of X- and Y-bearing sperm by means of centrifugation usually have been based on the assumption that smaller Y and larger X chromosomes might provide the difference in their apparent densities. The present results suggest that the separation cannot be due merely to a difference in their densities.  相似文献   
77.
In order to clarify the role of gastric inhibitory polypeptide (GIP) in an enteroinsular axis, 19 healthy mongrel dogs were divided into following groups: 5 normal dogs (N), 4 dogs with gastrojejunostomy (GJ), 5 dogs with duodenal fistula (D) and 5 vagotomized dogs (V). Four weeks after the operation glucose was administered orally or intraduodenally in a conscious state. In group D, glucose administration was repeated under atropine injection (A). Glucose-induced response of plasma GIP was exaggerated in all the groups compared with group N. The regression equation reported by Lauritsen and Moody was obtained in each dog from the ratio of plasma insulin to blood glucose and from plasma GIP. The slope of the regression line was elevated in group GJ and reduced in group V. However, groups D and A did not reveal any difference in the slope of the regression line compared with group N. From the present study, it might be concluded that the B-values in Lauritsen and Moody's equation indicates the sensitivity of the B cell in the pancreatic islet and that GIP secretion plays an important role in the glucose-induced insulin response even in the conditions with various surgical modifications.  相似文献   
78.
When heat-killed Propionibacterium acnes, a gram-positive anaerobe, is intravenously injected into mice followed by an intravenous injection of gram-negative lipopolysaccharide (LPS) 7 days later, most of the mice die of massive hepatic cell necrosis within 24 hours of LPS injection. Using this experimental model, acute hepatic failure was induced in mice, and the tryptophan metabolism in the liver, brain and kidney was studied. As a result, the tryptophan level was remarkably high in all three organs, and the metabolism of both the tryptamine pathway and serotonin pathway was induced. However, in the brain, the tryptamine metabolism was more induced compared to the serotonin, suggesting that the metabolites of tryptamine, may be involved in hepatic encephalopathy.  相似文献   
79.
80.
Patients on long-term hemodialysis (HD) are known to develop amyloid osteoarthropathy, evidenced as cystic radiolucencies on X-rays of the affected joints. To study the relationship between cystic radiolucencies and amyloid osteoarthropathy in 394 patients, we classified the severity of the cystic radiolucencies seen in the wrist joint on a 4-point scale and evaluated the association between lesion severity (grade) and several parameters. Biopsy was performed in 8 patients with 11 bone cysts of the wrist joint who had been operated for carpal tunnel syndrome. HD for 10 years or longer, age 50 or older and the presence of carpal tunnel syndrome were associated with severe cyst rating. There was no association between lesion grade and serum level of PTH-C, aluminum or beta 2-microglobulin (B2M). Ten of the 11 biopsied bone cysts in 8 patients with carpal tunnel syndrome demonstrated amyloid deposits which reacted with B2M. We conclude that a cystic radiolucency observed in the wrist joint of a patient undergoing HD indicates the deposition of amyloid. The cyst grade provides a useful marker for the severity of amyloid osteoarthropathy in HD patients.  相似文献   
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