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101.
DD Epstein 《Canadian Metallurgical Quarterly》1995,14(1):84, 86, 88-84, 86, 89
102.
Of the 378 cases of stage 3 carcinoma uterine cervix, only 10 showed vesical invasion, while 19 of 24 cases of stage 4 disease had vesical invasion. Results of this procedure did not alter the management of the disease in any of these cases. From the whole series it was concluded that cysto-urethroscopy is an unnecessary, cost ineffective, invasive procedure which has no role in either diagnosis or in planning the definitive treatment of carcinoma uterine cervix. 相似文献
103.
Parametric analysis was made of the characteristics by which proximity and alignment serve as cues for perceptual grouping in rats. Rats were initially conditioned to discriminate a series of horizontal lines from vertical lines. Following training, rats were presented with test stimuli that consisted of bistable arrays of disjunct dots. A grouping cue (greater proximity, greater alignment, or both) was randomly assigned to either the horizontal or vertical orientation. The effectiveness of the cues was based on behavioral responses to the cued orientation. Results indicated that proximity served as a cue for perceptual grouping. The effectiveness of the proximity cue was less for rats than found previously in humans and, unlike humans, diminished with increased stimulus scale. Rats did not respond to alignment cues when used in isolation, although alignment facilitated grouping when used in conjunction with proximity cues. Diminished effectiveness of grouping cues likely reduces object recognition abilities, particularly for complex visual stimuli. 相似文献
104.
We initiated a pilot study of adjuvant hepatic arterial infusion chemotherapy (AHAIC) using 5-fluorouracil (5-FU) and leucovorin. Hepatic arterial infusion ports were placed in 15 consecutive patients undergoing curative resection of colorectal liver metastases. The chemotherapy regimen consisted of a weekly infusion of 5-FU (12 mg m 2 per day) and leucovorin (200 mg m 2 per day) for 12 months. The mean follow-up was 22 months (range 3-62 months, SD 21-37 months). There were no clinical or biological complications related to chemotherapy, except for sharp epigastric burns in four patients immediately after 5-FU infusions. Catheter irreversible occlusions led to early cessation of the treatment in three patients. Four of the 15 evaluable patients developed recurrent disease. The site of relapse was the liver in two patients and extra-hepatic sites in the two remaining patients. Three of these four patients died of their recurrent disease. These results suggest that 5-FU and leucovorin can be combined for AHAIC in a long duration regimen with a very low rate of side-effects. This protocol could be safely employed in a prospective randomized study in combination with 5-FU systemic infusions. 相似文献
105.
106.
TM Mulders Keizer J Ouwerkerk EA van der Velde DD Breimer GJ Mulder 《Canadian Metallurgical Quarterly》1995,1(12):1525-1536
Several studies have suggested that the glutathione/glutathione S-transferase (GSH/GST) system is involved in resistance of tumors toward ifosfamide and other cytostatic agents. Besides, ifosfamide metabolites (in vitro) as well as ifosfamide treatment (in vivo) have been shown to decrease cellular GSH availability. In the present study, the in vivo effects of three different ifosfamide treatment schedules on the GSH/GST system were studied in patients with advanced cancers (n = 24): continuous i.v. infusions of 1300 mg/m2 daily for 10 days and 5000 mg/m2/day for 24 h, as well as a 4-h infusion of 3000 mg/m2 daily for 3 days. The GSH/GST system was characterized by administering bromisoval, a probe drug to assess GSH conjugation activity in vivo, as well as by daily monitoring of GSH concentrations in blood cells and plasma. Bromisoval pharmacokinetics was assessed before and at the end of the ifosfamide treatment. Blood cell GSH levels decreased significantly (P < 0.05) during the 3- and 10-day ifosfamide treatment schedules; the 24-h treatment had no effect. The ifosfamide treatment schedules had only minimal effects on bromisoval pharmacokinetics. Assuming that the kinetics of the probe drug provide an accurate reflection of enzyme activity, this suggests that GST activity remains unchanged. Because GSH conjugation of bromisoval enantiomers requires both GST activity and GSH availability, these results also indicate that, despite the 35% decrease in GSH in blood cells of two patient groups, the GSH availability of the cancer patients was not rate-limiting for GSH conjugation of bromisoval enantiomers. If GSH levels in blood cells reflect those in tumors/other tissues, the present results indicate that ifosfamide may be used clinically to decrease GSH levels. However, whether a 35% decrease is sufficient to increase tumor sensitivity toward (other) cytostatics remains uncertain. 相似文献
107.
MA Nett DP Cerretti DR Berson J Seavitt DJ Gilbert NA Jenkins NG Copeland RA Black DD Chaplin 《Canadian Metallurgical Quarterly》1992,149(10):3254-3259
IL-1 beta is a potent modulator of immune and inflammatory responses. Murine IL-1 beta is initially synthesized as an inactive 33-kDa pro-molecule that is activated by proteolytic cleavage between Asp-117 and Val-118 to generate the 17-kDa mature IL-1 beta protein. This cleavage is catalyzed by a specific protease that has been designated the IL-1 beta converting enzyme (or IL-1 beta convertase). We have used a human IL-1 beta convertase cDNA to isolate murine convertase cDNA from a WEHI-3 library. These cDNA predicted that the murine convertase is a 402-residue protein. Overall, the murine convertase showed 71% nucleotide and 62% predicted amino acid sequence identity with the human convertase. Southern blot analysis of interspecific backcross mice indicated that the murine IL-1 beta convertase is encoded by a single copy gene located on murine chromosome 9. The murine convertase showed broad constitutive expression, being detected in mononuclear phagocyte and T lymphocyte cell lines as well as in spleen, heart, brain, and adrenal glands. The expression of the murine convertase in mononuclear phagocytes was up-regulated by treatment with LPS or rIFN-gamma. These studies establish that the IL-1 beta convertase is an evolutionarily conserved, widely expressed enzyme that can be regulated at a pretranslational level. 相似文献
108.
S Daggubati JR Parks RM Overton G Cintron DD Schocken DL Vesely 《Canadian Metallurgical Quarterly》1997,36(2):246-255
OBJECTIVES:The present investigation was designed to determine the best endogenous plasma marker of early congestive heart failure (CHF). METHODS: Forty volunteers with mild CHF (New York Heart Association Class I, n = 12), moderate (Class II, n = 8), or severe (Class III and Class IV, each = n of 5) and 10 age-matched healthy individuals had the simultaneous evaluation of their respective plasma samples by the following radioimmunoassays: atrial natriuretic peptide, ANP; three N-terminal ANP prohormone assays, i.e., proANPs 1-30, 31-67, and 79-98 with the numbers referring to their amino acid (a.a.) sequences in their 126 a.a. prohormone; brain (BNP) and C-natriuretic peptides; N-terminal BNP prohormone; adrenomedullin; neuropeptide Y and endothelin. RESULTS: ProANPs 31-67, 1-30 and 79-98 had 100% (P = 0.01), 83% (P = 0.09) and 50% (P = 0.74) sensitivity in differentiating Class I CHF subjects from healthy subjects. The ANP, BNP, NT-proBNP, CNP, adrenomedullin, neuropeptide Y, and endothelin assays could not differentiate mild CHF subjects from healthy individuals. Logistic regression analysis revealed that only proANP 31-67 significantly (P = 0.0001) discriminated between early CHF (5226 +/- 377 pg/ml) and healthy individuals (1595 +/- 157 pg/ml). The positive and negative predicative values of proANP 31-67 were excellent (100% for each). The peptides measured in these assays were found to be independent markers of CHF with respect to left ventricular ejection fraction. CONCLUSIONS: ProANPs 31-67 is the most sensitive marker in discriminating NYHA Class I CHF subjects from healthy individuals. The ANP, BNP, NT-proBNP, CNP, adrenomedullin, neuropeptide Y and endothelin radioimmunoassays cannot discern mild CHF. These peptides are independent of left ventricular ejection fraction. 相似文献
109.
P Rainville GH Duncan DD Price B Carrier MC Bushnell 《Canadian Metallurgical Quarterly》1997,277(5328):968-971
Recent evidence demonstrating multiple regions of human cerebral cortex activated by pain has prompted speculation about their individual contributions to this complex experience. To differentiate cortical areas involved in pain affect, hypnotic suggestions were used to alter selectively the unpleasantness of noxious stimuli, without changing the perceived intensity. Positron emission tomography revealed significant changes in pain-evoked activity within anterior cingulate cortex, consistent with the encoding of perceived unpleasantness, whereas primary somatosensory cortex activation was unaltered. These findings provide direct experimental evidence in humans linking frontal-lobe limbic activity with pain affect, as originally suggested by early clinical lesion studies. 相似文献
110.
The prevalence of refractory partial seizure Thai patients at Prasat Neurological Institute was retrospectively from patient charts from January 1995-December 1996 and further prospectively analysed. All epileptic patients were screened by direct questions regarding the anti-epileptic drugs (AEDs) regimen, the frequency, nature of seizure attacks and risk factors of seizure. The criteria of clinical refractory partial seizure was defined as partial seizure which cannot be controlled by a combination of at least two AEDs for four weeks. The results were 3,018 cases of total epileptic patients out of 300,008 visits. These were classified as 2,802 cases of generalized seizures (92.8%), 184 cases of partial seizures (6.1%), and 32 cases of unclassified seizures (1.1%). In the partial seizures group, the number of clinical refractory partial seizures was found to be 48 cases (26.1% of partial seizure). We found that the major risk factor of refractory partial seizures was lack of therapeutic AEDs blood level monitoring (64.5% of cases) and the other risk factors were lack of compliance, loss of follow-up but continued medication, concomitant medication, and improper drug storage. AEDs dosage was adjusted until the blood levels were in the therapeutic range, and correction of other risk factors and patient counseling was given. The number of true refractory partial seizures was reduced to 10 cases (5.4% of partial seizure). This procedure revealed that AED blood level monitoring and correction of other risk factors were essential in controlling seizure frequency. Thus, the prevalence of true refractory partial seizure in our study was 3.3 cases of refractory partial seizure per 1,000 cases of the seizure population. We recommend that AEDs blood level monitoring and exclusion of other risk factors should be added to the criteria for the definition of refractory partial seizures. This criteria should be applied when considering the use of new AEDs as an add-on therapy in refractory Thai patients. 相似文献