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121.
D Osoba NK Aaronson M Muller K Sneeuw MA Hsu WK Yung M Brada E Newlands 《Canadian Metallurgical Quarterly》1996,5(1):139-150
A self-report questionnaire module consisting of 24 items, comprising 5 scales and 7 single items, has been developed for measuring health-related quality of life in patients with brain cancer. Module development proceeded through several stages, including a listing of patient, family and health care professional concerns, the writing of items, field testing in 105 patients with brain cancer and subsequent item reduction and scale construction after multitrait scaling analysis and assessment of internal consistency (Cronbach's coefficient alpha). The final version of the module exhibits reasonable test-retest stability over a period of one week. Differences in the responses between patients with recently-diagnosed and recurrent cancer and between patients with a Karnofsky Performance Score (KPS) of 50-70 and 80-100 were in the expected direction, indicating that the module of questions is responsive to differing conditions. Patients with either mental confusion, motor deficit or dysphasia indicated problems in several domains and single items as compared to patients without these neurological deficits. Thus, differences in the responses to the items in the brain cancer module appear to reflect differences in neurological status. In addition, deteriorating neurological status was accompanied by a marked increase in emotional distress, future uncertainty and motor dysfunction. A comparison of the responses in the module with the KPS and with a modified Barthel Activities of Daily Living Index (BADLI) shows moderate correlations, primarily with scales and items that pertain to motor dysfunction, while other scales (such as emotional distress, visual disorder and communication deficit) and most single items are not associated with the KPS or BADLI. Since the emotional distress scale of the module was found to be highly correlated with the emotional function scale of the EORTC QLQ-C30, it could be omitted when the module is used in combination with the QLQ-C30. This would reduce the module to a total of 20 items with four scales and seven single items. The intention is to combine this module of questions with other core or general quality-of-life questionnaires when studying patients with brain cancer in clinical trials. 相似文献
122.
The effects of various neurochemicals were examined in intact, unanesthetized rainbow trout (Oncorhynchus mykiss) to assess the role of branchial O2-sensitive chemoreceptors in the cardio-ventilatory responses to exogenous neurochemicals. cyanide stimulated ventilation and elicited bradycardia when give externally but only stimulated ventilation when injected internally. Norepinephrine increased heart rate, blood pressure and ventilatory rate but opercular pressure was not affect. Dopamine had no effect on either heart or ventilatory rate but increased blood pressure and decreased opercular pressure. Serotonin stimulated heart rate and ventilation but decreased blood pressure. Acetylcholine and nicotine stimulated all cardio-ventilatory variables. Muscarine decreased heart rate and blood pressure and had a biphasic effect on ventilation. These results, combined with the results from the preceding study, suggest that the cardio-ventilatory effects of exogenously administered (1) cyanide are entirely mediated by gill O2 receptors, (2) serotonin, and cholinergic drugs could be partly mediated by O2 receptors and (3) catecholaminergic drugs are not mediated by O2 receptors. 相似文献
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124.
GL Clayman AK el-Naggar SM Lippman YC Henderson M Frederick JA Merritt LA Zumstein TM Timmons TJ Liu L Ginsberg JA Roth WK Hong P Bruso H Goepfert 《Canadian Metallurgical Quarterly》1998,16(6):2221-2232
PURPOSE: Standard therapies of head and neck squamous cell carcinoma (HNSCC) often cause profound morbidity and have not significantly improved survival over the last 30 years. Preclinical studies showed that adenoviral vector delivery of the wild-type p53 gene reduced tumor growth in mouse xenograft models. Our purpose was to ascertain the safety and therapeutic potential of adenoviral (Ad)-p53 in advanced HNSCC. PATIENTS AND METHODS: Patients with incurable recurrent local or regionally metastatic HNSCC received multiple intratumoral injections of Ad-p53, either with or without tumor resection. Patients were monitored for adverse events and antiadenoviral antibodies, tumors were monitored for response and p53 expression, and body fluids were analyzed for Ad-p53. RESULTS: Tumors of 33 patients were injected with doses of up to 1 x 10(11) plaque-forming units (pfu). No dose-limiting toxicity or serious adverse events were noted. p53 expression was detected in tumor biopsies despite antibody responses after Ad-p53 injections. Clinical efficacy could be evaluated in 17 patients with nonresectable tumors: two patients showed objective tumor regressions of greater than 50%, six patients showed stable disease for up to 3.5 months, and nine patients showed progressive disease. One resectable patient was considered a complete pathologic response. Ad-p53 was detected in blood and urine in a dose-dependent fashion, and in sputum. CONCLUSION: Patients were safely injected intratumorally with Ad-p53. Objective antitumor activity was detected in several patients. The infectious Ad-p53 in body fluids was asymptomatic, and suggests that systemic or regional treatment may be tolerable. These results suggest the further investigation of Ad-p53 as a therapeutic agent for patients with HNSCC. 相似文献
125.
WK Anger DS Rohlman OJ Sizemore CA Kovera M Gibertini J Ger 《Canadian Metallurgical Quarterly》1996,18(4):371-379
Neurotoxic effects are of such breadth and complexity that functional biomarkers (behavioral tests) that integrate many areas of the nervous system predominate in human neurotoxicology research. The increasing distribution of chemical and other manufacturing throughout the world, particularly in developing nations, suggests the acute need to develop biomarkers for chemical exposures and effects that can be employed internationally. A language-free method for training performance on behavioral tests is described, which holds promise for international research that circumvents the vagaries of translation. Four behavioral tests were administered to 74-114 adult US subjects. Procedures, collectively termed shaping, produced effective performance on three tests [Symbol Digit, Vigilant Attention Test (VAT), Digit Span Forward and Backward], and produced appropriate but unacceptably slow performance in initial testing on the Simple Reaction Time test. Effective performance on the Symbol-Digit test also was produced by shaping instruction, without assistance from examiners, in small groups of residents of Taipei (Taiwan) and US children between the ages of 5 and 16. 相似文献
126.
127.
Cloning, expression, and primary structure of Metapenaeus ensis tropomyosin, the major heat-stable shrimp allergen 总被引:1,自引:0,他引:1
PS Leung KH Chu WK Chow A Ansari CI Bandea HS Kwan SM Nagy ME Gershwin 《Canadian Metallurgical Quarterly》1994,94(5):882-890
Shrimp is a common cause of seafood hypersensitivity. To study the mechanism of seafood hypersensitivity at the molecular level, we have determined the primary structure of the major heat-stable allergen of shrimp by cloning, expression, nucleotide sequencing, and amino acid sequence determination of an IgE-reactive cDNA clone, Met e I, isolated from a Metapenaeus ensis expression library in lambda gt 11. We first constructed a cDNA library from the shrimp M. ensis in lambda gt 11. We then screened the library with sera from patients with hypersensitivity reactions to shrimp and identified a positive IgE-reactive clone, designated as Met e I. This cDNA was purified to homogeneity and subsequently expressed in the plasmid pGEX. Serum antibodies from patients with shrimp allergy demonstrated positive IgE reactivity by immunoblotting to a protein encoded by the clone Met e I; sera from nonallergic control subjects were not reactive. The nucleotide sequence of this cDNA clone revealed an open reading frame of 281 amino acid residues, coding for a protein of 34 kd. Comparison of the Met e I amino acid sequence with the Genbank database showed that Met e I is highly homologous to multiple isoforms of tropomyosin. 相似文献
128.
We have previously shown that 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) plays a major role in growth zone chondrocyte (GC) differentiation and that this effect is mediated by protein kinase C (PKC). The aim of the present study was to identify the signal transduction pathway used by 1,25(OH)2D3 to stimulate PKC activation. Confluent, fourth passage GC cells from costochondral cartilage were used to evaluate the mechanism of PKC activation. Treatment of GC cultures with 1,25(OH)2D3 elicited a dose-dependent increase in both inositol-1,4,5-trisphosphate and diacylglycerol (DAG) production, suggesting a role for phospholipase C and potentially for phospholipase D. Addition of dioctanoylglycerol to plasma membranes isolated from GCs increased PKC activity. Neither pertussis toxin nor choleratoxin had an inhibitory effect on PKC activity in control or 1,25(OH)2D3-treated GCs, indicating that neither Gi nor Gs proteins were involved. Phospholipase A2 inhibitors, quinacrine, OEPC (selective for secretory phospholipase A2), and AACOCF3 (selective for cytosolic phospholipase A2), and the cyclooxygenase inhibitor indomethacin decreased PKC activity, while the phospholipase A2 activators melittin and mastoparan increased PKC activity in GC cultures. Arachidonic acid and prostaglandin E2, two downstream products of phospholipase A2 action, also increased PKC activity. These results indicate that 1,25(OH)2D3-dependent stimulation of PKC activity is regulated by two distinct phospholipase-dependent mechanisms: production of DAG, primarily via phospholipase C and production of arachidonic acid via phospholipase A2. 相似文献
129.
130.
A comparative evaluation of the macrodilution method and the Alamar colorimetric method for the susceptibility testing of amphotericin B, fluconazole, and flucytosine was conducted with 134 pathogenic yeasts. The clinical isolates included 28 Candida albicans, 17 Candida tropicalis, 15 Candida parapsilosis, 12 Candida krusei, 10 Candida lusitaniae, 9 Candida guilliermondii, 18 Torulopsis glabrata, and 25 Cryptococcus neoformans isolates. The macrodilution method was performed and interpreted according to the recommendations of the National Committee for Clinical Laboratory Standards (document M27-P), and the Alamar colorimetric method was performed according to the manufacturer's instructions. For the Alamar colorimetric method, MICs were determined at 24 and 48 h of incubation for Candida species and T. glabrata and at 48 and 72 h of incubation for C. neoformans. The overall agreement within +/- 1 dilution for Candida species and T. glabrata against the three antifungal agents was generally good, with the values for amphotericin B, fluconazole, and flucytosine being 85.3, 77.9, and 86.2%, respectively, at the 24-h readings and 69.3, 65.2, and 97.2%, respectively, at the 48-h readings. Most disagreement was noted with fluconazole against C. tropicalis and T. glabrata. Our studies indicate that determination of MICs at 24 h by the Alamar colorimetric method is a valid alternate method for testing amphotericin B, fluconazole, and flucytosine against Candida species but not for testing fluconazole against C. tropicalis and T. glabrata. For flucytosine, much better agreement can be demonstrated against Candida species and T. glabrata at the 48-h readings by the Alamar method. Excellent agreement within +/- dilution can also be observed for amphotericin B, fluconazole, and flucytosine (80, 96, and 96%, respectively) against c. neoformans when the MICs were determined at 72 h by the Alamar method. 相似文献