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91.
PURPOSE: The aim of the present study was to investigate carcinoembryonic antigen (CEA), CA19.9, and CA72.4 in the serum and gastric juice of patients with gastric cancer. METHODS: Serum and gastric juice tumor markers CEA, CA19.9, and CA72.4 were measured in 59 patients who had gastric adenocarcinomas and were undergoing curative gastrectomy. The same markers were measured in 47 patients with benign gastric disorders and in 40 healthy subjects. The correlation between the serum and gastric juice levels of tumor markers and several clinicopathological factors were evaluated by univariate analysis. The significance of the tumor markers as prognostic factors was assessed both by univariate and multivariate analysis. RESULTS: The positivity rates of serum CEA, CA19.9, and CA72.4 were 57.6%, 38.9%, and 18.6% respectively. The positivity rates of gastric juice CEA, CA19.9, and CA72.4 were 62.7%, 30.5%, and 23.7% respectively. The combination of serum and gastric juice markers gave a positivity of 81.3%. There was no correlation between serum and gastric juice level of each tumor marker. Positivity of gastric juice markers did not correlate with prognosis. A significant difference in prognosis was observed between patients positive and negative for serum CEA and CA19.9. Multivariate analysis also revealed that serum CEA and CA19.9 levels were independent prognostic factors. CONCLUSIONS: Levels of both serum and gastric juice tumor markers continue to have only limited diagnostic usefulness in gastric cancer patients. CEA and CA19.9 in the preoperative sera are good prognostic factors, whereas the presence of tumor markers in the gastric juice does not play any prognostic role.  相似文献   
92.
For the cancer cells which have overcome the second mitotic clock (M2), activated telomerase is essential and used as another marker of immortality. Many trials had been initiated to target telomerase, which is known to be specific to tumors. To determine the best in vitro cell system for testing the efficacy of telomerase inhibitors, we evaluated the telomerase activity of various cancer cell lines and measured their telomere lengths. We also treated some cancer cell lines with adriamycin and measured the changes of telomerase activity. Telomerase activity was evaluated in various cell lines with the TRAP (telomeric repeat amplification protocol) assay. Telomerase activity was calculated and translated into arbitrary units by computer-assisted densitometry with the control of telomerase activity in the 293 control cell line. Also, terminal restriction fragment lengths were measured using Southern blotting. We also measured telomerase activity and telomere lengths in 11 benign breast tumor tissues and 19 paired stomach cancer and normal tissues. Cancer cell lines treated with adriamycin we evaluated for changes of telomerase activity and the cell proliferation by MTT assay and dye exclusion test. Telomerase activity of cell lines was 95.3 24.1 unit with a range of 27.6-129.6 unit, while the telomere lengths of those cell lines were variable from 5.0 to 10.4 kbp with a median of 6 kbp. In 11 cancer cell lines which were not yet firmly established, we could not detect any telomerase activity. Low telomerase activity was detected in only 2 benign tumor tissues of breast with a median telomere length of 8.8 (7-10.5) kbp. Among paired 19 gastric cancer and normal tissues, only 7 cancer tissues showed weak telomerase activity. After adriamycin treatment, telomerase activity in YCC-S-1, YCC-S-3, MCF-7 and MCF-7/ADR was decreased in accordance with the changes of the cell numbers. Telomerase is specific to cancer tissues and is expressed differently from organ to organ. Telomerase activity by TRAP assay could be used as a chemosensitivity assay.  相似文献   
93.
Recent animal experiments have shown that palatal repair without denudation of bone leads to a superior dento-alveolar development. The aim of this clinical study was to evaluate the peri- and postoperative course and the dento-alveolar development of the deciduous dentition in Japanese ULCP, and CP patients up to 5 years after two different types of palatal repair. One of the methods, the Kohama (1991) supraperiosteal flap technique, is performed without denudation of the bony palate, while the other, the Wardill (1937) push-back technique, results in areas of denuded bone. It was concluded that the supraperiosteal technique can be performed successfully in approximately the same amount of time as the push-back technique. Re-epithelialization of the wound areas after supraperiosteal repair takes about 1 week, which is one third of the time associated with healing after the push-back technique. Arch depth of the deciduous dentition after the supraperiosteal technique is superior compared to the push-back technique. The question of whether or not the supraperiosteal technique produces more favorable dento-alveolar development than the mucoperiosteal technique in the permanent dentition in humans has to be elucidated in future research.  相似文献   
94.
A three-dimensional, two-part model of the foot, for use in a simulation of human gait, is presented. Previous simulations of gait have not included the foot segment (e.g. Siegler et al., 1982, J. Biomechanics 15, 415-425) or have fastened it to the ground (e.g. Onyshko and Winter, 1980, J. Biomechanics 13, 361-368). A foot model based on viscoelastic elements (e.g. Meglan, 1991, Ph.D. thesis, Ohio State Univ.), allows more freedom of movement and thus models the physical system more closely. The current model was developed by running simulations of the foot in isolation from just before heel contact to just after toe-off. The driving inputs to the simulation were the resultant ankle joint forces and moments taken from a gait analysis. Nine linear, vertically oriented spring/damper systems, positioned along the midline of the foot were used to model the combined viscoelastic behaviour of the foot, shoe and floor. Associated with each vertical spring/damper system were two orthogonally placed, linear, horizontal dampers used to provide the shear components of the ground reaction force. Torques at the metatarsal-phalangeal joint were supplied by a linear, torsional spring and damper. Control about the vertical axis and the long axis of the foot was achieved by the use of linear, torsional dampers. The predicted kinetic and kinematic values are very similar to those taken from the gait analysis. The model represents an improvement over previous work because the transition from swing to stance was smooth and continuous without the foot being constrained to any specific trajectory.  相似文献   
95.
The sawdust (SD) waste generated in the timber industry was converted to a low‐cost activated carbon (SDAC) using a simpler and cheaper activation process, single‐step steam pyrolysis activation. The possibility of utilizing SDAC for the removal of lead (Pb(II)) in the absence of ligands and nitrilotriacetic acid (NTA) and ethylenediaminetetraacetic acid (EDTA) chelated Pb(II) complexes from the liquid phase was examined and the results were compared with those for commercial activated carbon (CAC). SDAC shows a high adsorption capacity for Pb(II) and Pb(II) chelates compared with CAC. The extent of adsorption of Pb(II) and Pb(II) chelates on activated carbons was found to be a function of solution pH and species distribution of Pb(II) and Pb(II) chelates. The optimum pH range for the removal of Pb(II) in the absence of ligands by SDAC was 6.5–8.0, whereas its maximum removal by CAC was observed at pH 6.5. In the presence of ligands, the extent of Pb(II) adsorption was enhanced in the pH range 2.0–5.0 and was reduced significantly in the pH range 6.0–8.0. The maximum uptake of Pb(II) chelates for both carbons was observed at pH 5.0. Kinetic models such as pseudo‐first‐order, pseudo‐second‐order and pore diffusion were tested to investigate the adsorption mechanism. Batch kinetic studies showed that the adsorption of Pb(II) from aqueous solutions with and without ligands could be best described by a psuedo‐first‐order model for both carbons. The effect of pH on the adsorption isotherms of Pb(II) and Pb(II) chelates was also investigated. The applicability of the Langmuir and Freundlich isotherms, established for various initial concentrations of the adsorbate and for different pH values, was tested at 30 °C. Copyright © 2003 Society of Chemical Industry  相似文献   
96.
In a prospective randomised study we investigated end-tidal carbon dioxide levels during standard versus active compression-decompression (ACD) cardiopulmonary resuscitation (CPR) assuming that the end-tital carbon dioxide reflects cardiac output during resuscitation. In each group 60 patients with out-of-hospital cardiac arrest were treated either with the standard or the ACD method. End-tidal CO2 (p(et)CO2, mmHg) was assessed with a side-stream capnometer following intubation and then every 2 min up to 10 min or restoration of spontaneous circulation (ROSC). There was no difference in p(et)CO2 between both patient groups. However, CO2 was significantly higher in patients who were admitted to hospital as compared to patients declared dead at the scene. All of the admitted patients had a p(et)CO2 of at least 15 mmHg no later than 2 min following intubation, none of the dead patients ever exceeded 15.5 mmHg. From these data we conclude that capnometry adds valuable information to the estimation of a patient's prognosis in the field (threshold, 15 mmHg), but we could not detect any difference in p(et)CO2 between ACD and standard CPR.  相似文献   
97.
Although numerical chromosomal aberrations are commonly seen in acute myeloid leukemia (AML), trisomy 5 (+ 5) is very rarely detected. We report two patients, both of whom suffered from acute monocytic leukemia, in which + 5 was found in hyperdiploid clones. A review of the English literature shows 17 additional cases of AML with + 5 in at least one of the abnormal clones, making a total of 19 such cases including ours. Trisomy 5 has been reported in all FAB subtypes of AML except acute promyelocytic leukemia. In the 19 cases identified in this report, + 5 was found in association with other numerical changes (four cases), structural changes (five cases) or both (eight cases). Trisomy 5 as a sole karyotypic abnormality was exceedingly rare (two cases). Its biologic and prognostic significance remains to be determined.  相似文献   
98.
Diets containing 300 mg fumonisin B1 (FB1)/kg of feed and 5 mg T-2 toxin/kg of feed singly or in combination were fed to female turkey poults (Nicholas Large White) from day of hatch to 21 d of age. When compared with controls, 21-d body weight gains were reduced 21% by FB1, 26% by T-2, and 47% by the combination. the efficiency of feed utilization was adversely affected by FB1 and the combination of FB1 and T-2. Relative weights (grams/100 g BW) of the liver and gizzard were increased in poults fed the FB1 and the combination diets; whereas, the relative weight of the pancreas was increased in all treated groups. All poults were scored for oral lesions using a scale of 1 to 4 (1 = no visible lesions, 4 = severe lesions). Oral lesions were present in all poults fed the T-2 diet (average score of 3.29) or the combination diet (average score of 3.54). Serum concentration of cholesterol was decreased and lactate dehydrogenase activity was increased in poults fed the FB1 and combination diets. The activity of aspartate aminotransferase and the values for red blood cells, hemoglobin, and hematocrit were increased only in poults fed the combination diet. Inorganic phosphorus concentration was decreased only in poults fed the combination diet. The increased toxicity in poults fed the combination diet for most variables can best be described as additive, although some variables not altered by FB1 or T-2 singly were significantly affected by the combination, indicating that the combination may pose a potentially greater problem to the turkey industry than either of the mycotoxins individually.  相似文献   
99.
Senna (60 mg/kg orally) and cascara (800 mg/kg orally)-induced diarrhoea and net fluid secretion were studied in rats for a time period of 1-8 h. NG-Nitro-L-arginine methyl ester (L-NAME) (2.5-25 mg/kg i.p. twice, 15 min before and 4 h after laxative administration), an inhibitor of nitric oxide synthase, reduced the diarrhoeal response. This effect was counteracted by L-arginine (600 and 1500 mg/kg i.p. 15 min before laxative administration), the precursor of nitric oxide (NO). The senna- and cascara-stimulated fluid secretion was reduced by NG-nitro-L-arginine methyl ester 25 mg/kg i.p. (twice, 15 min before and 4 h after laxative administration), while the stereoisomer NG-nitro-D-arginine methyl ester (D-NAME) 25 mg/kg i.p. was without effect. These results suggest a possible involvement of NO in senna- and cascara-induced diarrhoea and fluid secretion.  相似文献   
100.
The possible subdivision of thromboxane A2-sensitive (TP) receptors is currently a controversial subject. We report herein on a novel thromboxane A2 mimetic, AGN 191976, which has almost identical pharmacological activity to the well-characterized prostaglandin H2/thromboxane A2 (PGH2/TxA2) mimetic U-46619, but its effects on intraocular pressure are quite distinct from U-46619. Prostanoid receptor activity was determined in vitro using different smooth muscle assays and platelets. Intraocular pressure was measured tonometrically in ocular normotensive Beagle dogs and Cynomolgus monkeys. Conjunctival microvascular permeability was determined in guinea pigs. Despite closely resembling U-46619 as a potent and selective TP receptor agonist, AGN 191976 was a potent ocular hypotensive in dogs and monkeys whereas U-46619 did not lower IOP in either species. The ocular hypotensive effect of AGN 191976 in dogs was attenuated by pretreatment with the TP receptor antagonist SQ 29548. Thus, the ocular hypotensive effects of AGN 191976 are consistent with TP receptor stimulation. Both TxA2-mimetics caused plasma leakage in the guinea pig conjunctiva. The disparate activities of U-46619 and AGN 191976 in our studies suggest the existence of heterogeneous populations of TP-receptors in the eye.  相似文献   
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