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171.
Diet has a definite role in certain gastrointestinal disorders, and dietary manipulation often is beneficial. In other cases, such as peptic ulcer, traditional dietary therapy cannot be justified by available evidence. 相似文献
172.
R Martínez Monge M Jurado I Azinovic JJ Aristu E Tangco JC Viera JM Berián FA Calvo 《Canadian Metallurgical Quarterly》1993,28(2):127-133
In ten patients with chronic renal failure (CRF) serum concentrations of alpha 1-acid glycoprotein, alpha 1-antitrypsin, prealbumin, hemopexin, transferrin, haptoglobin, C3c and C4 complement components, ceruloplasmin, alpha 2-macroglobulin were determined using Partigen plates before, 30 min. and 2 hours after beginning of HD. Serum concentrations of C3c complement component, prealbumin increased significantly during HD using CU dialyser, but changes during HD using CA dialyser were not significant. Serum concentrations of alpha 1-antitrypsin, hemopexin increased significantly after two hours of HD using CA dialyser, but changes during HD using CU dialyser were again not significant. Serum concentrations of alpha 1-acid glycoprotein, transferrin, haptoglobin, ceruloplasmin, C4 complement component during HD using both dialyzers did not change significantly. Serum concentration of alpha 2-macroglobulin was higher after two hours of HD. The type of dialysis membrane has important influence on changes of serum acute phase proteins during the initial period of HD. 相似文献
173.
174.
B Saad FA Scholl H Thomas H Schawalder V Streit F Waechter P Maier 《Canadian Metallurgical Quarterly》1993,213(2):805-814
The influence of cell-substrata interactions on the preservation of basal or in-vivo-induced microsomal cytochrome P-450 isoenzyme contents in cultured rat hepatocytes and on the adaptive responses after exposure to phenobarbital or 3-methylcholanthrene in vitro, was investigated. Hepatocytes from untreated or phenobarbital-treated rats were cultured in serum-free, aprotinin-supplemented culture medium in 96-well microtiter plates coated with collagen type I (COL), laminin, fibronectin or crude liver membrane fractions/collagen type I (CMF/COL). Basal cell functions were characterized by measuring the total protein content and lactate dehydrogenase release. The relative contributions of CYP1A1/2, CYP2B1/2, CYP2C6, CYP2C11, CYP3A and CYP4A isoenzymes were determined with ELISA using monoclonal antibodies raised against purified cytochromes P-450 from rat liver microsomes. The characterization of the CMF revealed that contaminations with mitochondria, nuclei and lysosomes are relatively low. Among these, membranes derived from the endoplasmic reticulum appeared to be the major organelle contaminant of the CMF. The matrix components laminin, fibronectin and collagen type IV were found in appreciable amounts. Hepatocytes from untreated rats, cultured for up to nine days on CMF/COL-coated plates, retained their relative cytochrome P-450 contents at 1.5-3-fold higher levels when compared to cells cultured on COL, fibronectin or laminin. Similarly, hepatocytes from phenobarbital-treated rats preserved the contents of barbiturate-inducible CYP2B1/2 and CYP3A proteins best when cultured on CMF/COL. After exposure of hepatocytes cultured on CMF/COL to phenobarbital from days 3-6, CYP3A proteins were enhanced more than twofold and CYP2B1/2, depending on the exposure level, increased 1.3-6-fold. After exposure to 3-methylcholanthrene, a threefold increase of CYP1A proteins was found in CMF/COL and laminin cultures. These results indicate that CMF/COL, as a substratum in rat hepatocyte cultures, regulates gene expression of cytochromes P-450 isoenzymes for up to 9 days and provides a matrix which enables the cells to respond qualitatively similar to the response observed in different zones of the liver. This activity cannot be replaced by single-matrix components. 相似文献
175.
PURPOSE: The addition of combination chemotherapy to standard radiation therapy has improved treatment for locally unresectable non-small-cell lung cancer. In this phase II study, we evaluated the toxicity and efficacy of a novel chemotherapy regimen that included paclitaxel, cisplatin, and etoposide plus concurrent radiation therapy in this group of patients. PATIENTS AND METHODS: Thirty-three patients with previously untreated, unresectable stage III non-small-cell lung cancer (stage IIIA, 11 patients; stage IIIB, 22 patients) initially received two courses of chemotherapy, which included paclitaxel 135 mg/m2 by 1-hour infusion on day 1, cisplatin 60 mg/m/ intravenously (i.v.) on day 2, and etoposide 100 mg/m2 i.v. on days 1, 2 and 3. On week 6, radiation therapy (60 Gy in 30 fractions) was initiated in conjunction with two additional courses of chemotherapy: paclitaxel 135 mg/m2 i.v. by 1-hour infusion on day 1, cisplatin 5 mg/m2 i.v. on days 2- to 10, and etoposide 25 mg/m2 on days 1 to 10. RESULTS: This combined modality program was feasible and well tolerated by most patients. During the two courses of induction chemotherapy, grade 3 or 4 myelosuppression occurred in only six patients (18%). Esophagitis was common during combined modality therapy (grade 3, 10 patients; grade 4 five patients). Forty-two percent of patients had partial response after two courses of induction therapy, and 82% of patients had an objective response at completion of therapy. Twelve patients (36%) had a complete response. Nineteen patients remain progression-free at a median of 8 months; the median survival time has not been reached. CONCLUSION: This paclitaxel-containing combined modality therapy is feasible and highly active in patients with inoperable stage III lung cancer. Esophagitis is the most common severe toxicity with this program. Further studies with paclitaxel-containing combination regimens in patients with stage III non-small-cell lung cancer are indicated. 相似文献
176.
177.
J Adnane FA Bizouarn Y Qian AD Hamilton SM Sebti 《Canadian Metallurgical Quarterly》1998,18(12):6962-6970
178.
Between October 1990 and June 1992, 89 patients underwent aortic valve replacement using the Intact porcine bioprosthesis. Their mean age (+/- SD) was 74.6 +/- 7.8 years (range 48 to 92). Seventy-five percent were in NYHA Class III-IV, 79 (89%) had AS or AS/AI, 10 (11%) had had previous cardiac surgery and 25 (32%) had an EF < 0.50. Associated procedures included CABG 45 (51%), septal myectomy 13 (15%), annular enlargement eight (9%), LV aneurysmectomy one, ascending aortic replacement one, and arch replacement one. Hospital mortality was four (4.5%). Hemodynamics were assessed with 2D echo with Doppler at seven days, six weeks and 12 months, and compared with 130 standard Carpentier-Edwards (C-E) porcine bioprostheses. At follow up, two patients have 2/4 perivalvular AI. The transvalvular gradients for the Intact valve were as follows: 21 mm-16.9 +/- 7.4 mmHg; 23 mm-18.9 +/- 6.2 mmHg; 25 mm-17.1 +/- 5.4 mmHg; 27 mm-15.0 +/- 3.7 mmHg; and 29 mm-15.0 +/- 2.1 mmHg. When compared to the standard Carpentier-Edwards porcine bioprostheses, the 21 mm Intact valve had the same gradient as the C-E prosthesis. However, the transvalvular gradients were slightly higher for the Intact valve for sizes 23-29 mm when compared to the corresponding C-E valve. The effective orifice area and effective orifice area index was no different between the two valves. Satisfactory hemodynamics are seen in the smaller prostheses when valves are matched for BSA and when aortic annular enlargement is performed when necessary. 相似文献
179.
Information regarding orthodontic service provision by general dental practitioners in Australia is limited. The aim of this survey was to determine the amount and variety of orthodontic services provided by general dental practitioners in the Melbourne Statistical Division, Victoria, Australia. A random sample of 307 dentists drawn from the Victorian Dentists Register was surveyed by mailed questionnaire: 218 (71%) replied. Data were collected using a fortnight log. During this time 59 per cent of the dentists saw at least one orthodontic patient; one dentist saw 66 orthodontic patients. Removable orthodontic appliances were used by 35 per cent of the dentists and fixed orthodontic appliances by 18 per cent. Twenty-six per cent provided comprehensive orthodontic treatment, 22 per cent aligned incisors, and 21 per cent corrected anterior crossbites. The general dental practitioners surveyed provided a wide range of preventive and interceptive orthodontic services to generally a small percentage of their patients. 相似文献
180.
SJ Montain SA Smith RP Mattot GP Zientara FA Jolesz MN Sawka 《Canadian Metallurgical Quarterly》1998,84(6):1889-1894
The purpose of this study was to determine whether hypohydration reduces skeletal muscle endurance and whether increased H+ and Pi might contribute to performance degradation. Ten physically active volunteers (age 21-40 yr) performed supine single-leg, knee-extension exercise to exhaustion in a 1.5-T whole body magnetic resonance spectroscopy (MRS) system when euhydrated and when hypohydrated (4% body wt). 31P spectra were collected at a rate of one per second at rest, exercise, and recovery, and were grouped and averaged to represent 10-s intervals. The desired hydration level was achieved by having the subjects perform 2-3 h of exercise in a warm room (40 degrees C dry bulb, 20% relative humidity) with or without fluid replacement 3-8 h before the experiment. Time to fatigue was reduced (P < 0.05) by 15% when the subjects were hypohydrated [213 +/- 12 vs. 251 +/- 15 (SE) s]. Muscle strength was generally not affected by hypohydration. Muscle pH and Pi/beta-ATP ratio were similar during exercise and at exhaustion, regardless of hydration state. The time constants for phosphocreatine recovery were also similar between trials. In summary, moderate hypohydration reduces muscle endurance, and neither H+ nor Pi concentration appears to be related to these reductions. 相似文献