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991.
H Wieler K Marohl KP Kaiser P Klawki H Fr?ssler 《Canadian Metallurgical Quarterly》1993,18(2):104-109
To investigate the relationships between the mammographic aspects (according to Broberg), proliferative activity and hormone receptor status, we studied 165 patients subjected to radical mastectomy for operable breast cancer. The highest percentage of estrogen receptor-positive cases was observed in mammograph class I (p < 0.02) while classes III and V were highest in progesterone receptor-positive cases. Proliferative activity (111 cases) was significantly lower in class I and IV with respect to all other classes (p < 0.03 and p < 0.01, respectively). This study suggests that certain mammographic signs can be related to the biological characteristics of breast cancer. 相似文献
992.
KP O'Boyle K Freeman A Kalisiak A Agregado DA Scheinberg 《Canadian Metallurgical Quarterly》1996,21(3-4):255-266
Twenty seven B cell neoplasms were examined by high performance thin layer chromatography (HPTLC) and immune thin layer chromatography (ITLC) to determine ganglioside expression. Patterns of expression in the cells were compared with conventional morphology, genotype, and glycoprotein immunophenotype. Patterns of ganglioside expression were found for each of the tumor types analyzed (5 acute lymphoblastic lymphomas (ALL), 5 Burkitt's Lymphomas (BL), 4 chronic lymphocytic leukemias (CLL), and 3 diffuse poorly differentiated lymphomas (DPDL), 7 diffuse histiocytic lymphomas (DHL), and 3 multiple myelomas (MM). GM3 was the predominant ganglioside found in all B cell neoplasms except multiple myeloma where GM2 was equivalent to GM3. GM1 was detected by ITLC in all B cell tumors, but significant amounts were found by HPTLC only in ALL, CLL, and DHL. Small amounts of GD3 and GD2 were found in several B cell neoplasms. Significant amounts of other gangliosides were not found. The expression of GM2 on the MM cell lines, a cell type derived from outside of the nervous system, is unusual. This high level of expression was also seen in metabolic labeling studies. GM2 was readily detectable in the SKMM1 human multiple myeloma cell line by flow cytometry and served as a target for human complement-mediated cytotoxicity. Although the functions of gangliosides are largely known, the patterns of gangliosides found for this system of human B cell malignancies may serve to provide targets for specific immunotherapy and clues to their functions. 相似文献
993.
EL Buytenhuijs HJ Berger KP Van Spaendonck MW Horstink GF Borm AR Cools 《Canadian Metallurgical Quarterly》1994,32(3):335-342
Parkinson's disease patients (PD) do not differ from control subjects (CS) when they have to execute a problem solving task in which external cues for solving the problem are given. However, when PD have to solve a problem by means of an internally generated strategy, they show a serious decrease in performance. We hypothesised that this distinction may also apply to the way PD and CS organize recall. In order to test our hypothesis the California Verbal Learning Test (CVLT) was administered to 59 PD and 30 CS. The test consists of five learning trials using a 16-word target list, composed of four items from each of four semantic categories. The fact that the word list was built on this implicit organization was not divulged in advance. The sequence in which the words were read is fixed; each subsequent word belongs to a category being different from the category to which the preceding word belongs. The organization in recall according to the semantic categories is considered to be the result of an unprompted, internally generated strategy. Recall according to the sequence in which the words are read by the experimenter, is viewed as an externally offered strategy. The results prove to be in line with our hypothesis: unlike CS who appeared to rely mainly and increasingly on an internally generated semantic organization, PD showed evidence of gradually adhering more to the externally imposed serial sequence. 相似文献
994.
MW Borgdorff LR Barongo JN Newell KP Senkoro W Devillé JP Velema RM Gabone 《Canadian Metallurgical Quarterly》1994,70(6):378-383
High resolution, magnetic resonance imaging was used to quantitatively study the morphometry of the superior oblique muscles of two patients with superior oblique myokymia, as well as 18 superior oblique muscles of 14 patients with normal superior oblique function. The cross sectional area of each superior oblique muscle was measured at 3-millimeter intervals along the entire muscle length. In both cases of myokymia, the affected superior oblique muscles were significantly smaller than normal (P < .05). These anatomical changes in the superior oblique muscle of patients with myokymia suggest that an antecedent injury to the trochlear nerve has occurred. This injury, even if clinically unapparent, may be the initial event which leads to subsequent development of superior oblique myokymia. 相似文献
995.
This report describes a 29-year-old bodybuilder taking anabolic steroids who presented with urinary retention, arthralgias, and peripheral edema, subsequently developed acute lower-extremity paralysis, and was diagnosed as having transverse myelitis and membranous glomerulonephritis secondary to systemic lupus erythematosus (SLE). The association of anabolic steroid use and hyperprolactinemia, and their possible link to the development of SLE, are reviewed. 相似文献
996.
JC Weeks EF Cook SJ O'Day LM Peterson N Wenger D Reding FE Harrell P Kussin NV Dawson AF Connors J Lynn RS Phillips 《Canadian Metallurgical Quarterly》1998,279(21):1709-1714
CONTEXT: Previous studies have documented that cancer patients tend to overestimate the probability of long-term survival. If patient preferences about the trade-offs between the risks and benefits associated with alternative treatment strategies are based on inaccurate perceptions of prognosis, then treatment choices may not reflect each patient's true values. OBJECTIVE: To test the hypothesis that among terminally ill cancer patients an accurate understanding of prognosis is associated with a preference for therapy that focuses on comfort over attempts at life extension. DESIGN: Prospective cohort study. SETTING: Five teaching hospitals in the United States. PATIENTS: A total of 917 adults hospitalized with stage III or IV non-small cell lung cancer or colon cancer metastatic to liver in phases 1 and 2 of the Study to Understand Prognoses and Preferences for Outcomes and Risks of Treatments (SUPPORT). MAIN OUTCOME MEASURES: Proportion of patients favoring life-extending therapy over therapy focusing on relief of pain and discomfort, patient and physician estimates of the probability of 6-month survival, and actual 6-month survival. RESULTS: Patients who thought they were going to live for at least 6 months were more likely (odds ratio [OR], 2.6; 95% confidence interval [CI], 1.8-3.7) to favor life-extending therapy over comfort care compared with patients who thought there was at least a 10% chance that they would not live 6 months. This OR was highest (8.5; 95% CI, 3.0-24.0) among patients who estimated their 6-month survival probability at greater than 90% but whose physicians estimated it at 10% or less. Patients overestimated their chances of surviving 6 months, while physicians estimated prognosis quite accurately. Patients who preferred life-extending therapy were more likely to undergo aggressive treatment, but controlling for known prognostic factors, their 6-month survival was no better. CONCLUSIONS: Patients with metastatic colon and lung cancer overestimate their survival probabilities and these estimates may influence their preferences about medical therapies. 相似文献
997.
BHRF1, a component of the restricted early antigen complex of the Epstein-Barr virus lytic cycle, encodes a 17-kDa protein with both sequence and functional homology to the antiapoptotic Bcl-2 oncogene. Recent work has suggested that BHRF1 behaves like Bcl-2 in protecting cells from apoptosis induced by a range of stimuli. In this study, the effect of BHRF1 and Bcl-2 on the growth and differentiation of the SCC12F human epithelial cell line was examined. The levels of stable transfected BHRF1 expression achievable in SCC12F cells was consistently lower than that obtained with Bcl-2. While both BHRF1 and Bcl-2 inhibited epithelial differentiation, the effect of Bcl-2 was more pronounced, resulting in an almost complete blockade of differentiation in organotypic raft cultures. However, BHRF1-expressing SCC12F cells proliferated at a much higher rate than SCC12F cells expressing Bcl-2, and this effect was supported by cell cycle analysis which demonstrated that BHRF1, but not Bcl-2, promotes rapid transit through the cell cycle. These data highlight important differences between BHRF1 and Bcl-2 and suggest that BHRF1 may function to promote the survival and proliferation of lytically infected cells. The proliferative properties of BHRF1 described in this study, together with the demonstration that other oncogenic gamma herpesviruses encode Bcl-2 homologues, suggests that these proteins may serve to increase the susceptibility of virus-infected cells to oncogenic transformation, thereby contributing to the development of virus-associated tumors. 相似文献
998.
Hyaluronan (HA), an abundant nonsulfated glycosaminoglycan component of synovial fluid and the extracellular matrix, is an attractive building block for new biocompatible and biodegradable polymers that have applications in drug delivery, tissue engineering, and viscosupplementation. This review consists of three subtopics: (i) chemical modification of HA; (ii) physicochemical and biochemical characterization of HA derivatives; and (iii) in vitro and in vivo bioevaluation studies. Important new products have already reached the marketplace, and the approval and introduction of a variety of new medical applications of HA-based biomaterials can be anticipated in the next decade. 相似文献
999.
VP Kalinovsky NY Volfson GB Pliss AR Shumakov KP Hanson 《Canadian Metallurgical Quarterly》1997,16(4):369-371
Nebulization of lignocaine is a common technique for preparing the airway prior to awake intubation. The aim of the study was to assay the serum levels of lignocaine. Ten ASA I volunteers had 6 mg/kg of 10% lignocaine solution nebulized via facemask. Blood assays for peak levels were performed. Mean peak serum lignocaine level was 0.29 mg/l with a highest measurement of 0.45 mg/l. This peak occurred 30 minutes following commencing nebulization. No subject developed symptoms or signs of lignocaine toxicity. Peak plasma lignocaine levels were an order of magnitude below the accepted toxic threshold of 5 mg/l. This indicates that supplemental doses of lignocaine via the bronchoscope can be given with safety. 相似文献
1000.
D Dawson 《Canadian Metallurgical Quarterly》1997,21(18):245-249
The Australian Mycobacterium Reference Laboratory Network collected and analysed laboratory data on isolates of Mycobacterium tuberculosis reported during 1994 and 1995. The total number of confirmed isolates was 708 in 1994 and 705 in 1995. This represents an annual incidence of approximately 4 cases of laboratory confirmed tuberculosis per 100,000 population. These figures are similar to those reported in previous years and confirms that the incidence of tuberculosis in Australia remains stable. The incidence rate varied between States. Overall the male:female ratio fell, and there were signs of a downward shift in the median age. We were unable to assess the impact of HIV infection on the number of isolates reported. Positive microscopy was obtained in 55-60% of patients with pulmonary disease. Approximately 8% of isolates had in vitro resistance to at least one of the four standard anti-tuberculosis drugs. Over the two year period seven strains were found to be multi-drug resistant. Overall, the data from 1994-1995 gives no indication of a significant change in the drug susceptibility profiles of isolates from Australian patients with tuberculosis. 相似文献