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991.
SF Thijsen GJ Schuurhuis JW van Oostveen AP Theijsmeijer AW Niewint GJ Ossenkoppele 《Canadian Metallurgical Quarterly》1997,20(10):835-842
Although the mobilization and harvesting of Philadelphia chromosome-negative progenitors has been proven feasible by a number of groups, it is not clear which techniques should be used with regard to the monitoring of purging and evaluation of stem cell yield. Therefore, we isolated CD34-positive cells from leukapheresis samples of seven CML patients after induction therapy. These cells were analyzed using the colony-forming unit granulocyte-macrophage (CFU-GM) and long-term culture-initiating cell (LTCIC) assays. In addition, we analyzed frequency and clonogenicity of single stem cells using the LTCIC assay at limiting dilution. Individual colonies derived from these assays were subsequently analyzed for the presence of the bcr-abl gene with interphase fluorescence in situ hybridization (FISH) and for the presence of bcr-abl mRNA with RT-PCR. We compared these results with the cytogenetic analysis of the leukapheresis material. Molecular analysis of individual colonies correlated well with the results of cytogenetic analysis. However, in nine out of 18 samples, cytogenetic analysis exclusively demonstrated the presence of either Philadelphia chromosome-positive or -negative cells whereas with the molecular analysis of individual colonies tumor contamination or the presence of residual normal cells could be substantiated. We concluded that molecular analysis of individual colonies should be employed to further optimize induction protocols. With regard to stem cell mobilization we demonstrated that about 67 CFU-GM colonies and clusters were generated by one single LTCIC both for the CML samples and the samples obtained from patients with non-hematologic malignancy. This number is important since until now most centres use a number of four colonies and clusters generated by one LTCIC. Dividing the CFU-GM output in the LTCIC assay by four to determine LTCIC frequency could thus lead to an almost 20-fold overestimation of the LTCIC frequency. It is concluded that stem cell frequency analysis is an important tool with regard to the interpretation of mobilization protocols. 相似文献
992.
KE Slegtenhorst-Eegdeman M Verhoef-Post M Parvinen JA Grootegoed AP Themmen 《Canadian Metallurgical Quarterly》1998,4(7):649-656
In immature rat Sertoli cells, leucine-rich primary response gene 1 (LRPR1) represents a follicle stimulating hormone (FSH)-responsive gene; the function of the encoded protein is not yet known. LRPR1 mRNA expression is up-regulated very rapidly and specifically by FSH, both in cultured Sertoli cells and in vivo in regulation in more detail, in testis and ovary of fetal, immature, and adult rats. In addition, we have studied the expression of FSH receptor (FSHR) mRNA in relation to LRPR1 mRNA expression. In rat testis, LRPR1 mRNA and FSHR mRNA followed a similar expression pattern, during postnatal development and also at different stages of the spermatogenic cycle in the adult rat. Furthermore, after short-term challenge of the FSH signal transduction pathway in intact immature rats by injection with a relatively high dose of FSH, an inverse relationship between LRPR1 mRNA (up-regulation) and FSHR mRNA expression (down-regulation) was observed. Similar studies in the ovary provided completely different results. LRPR1 mRNA in the postnatal ovary is present well before expression of FSHR mRNA can be first detected. In addition, incubation of ovaries of immature rats with FSH or dibutyryl cyclic AMP (dbcAMP) did not result in up-regulation of LRPR1 mRNA expression. During fetal development, the LRPR1 mRNA expression pattern involved many more tissues, in contrast to the relatively tissue-specific expression of LRPR1 mRNA in gonads of 21 day old and adult rats. Moreover, LRPR1 mRNA expression could be detected as early as 12.5 days post-coitum, whereas FSHR mRNA is absent at this stage of fetal development. We concluded that the pronounced regulation of LRPR1 by FSH observed in the immature rat testis does not occur in the ovary. Furthermore, in the ovary LRPR1 mRNA expression does not appear to be dependent on FSH action. Finally, the LRPR1 gene product may play a general role during fetal development. 相似文献
993.
MS Mizel HT Temple JD Michelson RG Alvarez TO Clanton CC Frey AP Gegenheimer SR Hurwitz LD Lutter MG Mankey RA Mann RA Miller EG Richardson LC Schon FM Thompson ML Yodlowski 《Canadian Metallurgical Quarterly》1998,(348):180-185
Thromboembolic disease presents a potentially fatal complication to patients undergoing orthopaedic surgery. Although the incidence after hip and knee surgery has been studied and documented, its incidence after surgery of the foot and ankle is unknown. For this reason, a prospective multicenter study was undertaken to identify patients with clinically evident thromboembolic disease to evaluate potential risk factors. Two thousand seven hundred thirty-three patients were evaluated for preoperative risk factors and postoperative thromboembolic events. There were six clinically significant thromboembolic events, including four nonfatal pulmonary emboli, after foot and ankle surgery. The incidence of deep vein thrombosis was six of 2733 (0.22%) and that of nonfatal pulmonary emboli was four of 2733 (0.15%). Factors found to correlate with an increased incidence of deep vein thrombosis were nonweightbearing status and immobilization after surgery. On the basis of these results, routine prophylaxis for thromboembolic disease after foot and ankle surgery probably is not warranted. 相似文献
994.
Work-related psychological distress (burnout) is a probable cause of drop-out among emotional support volunteers (buddies) who work with people living with AIDS. In addition to the emotional suffering and disruption to both the buddy and the buddied, burnout has significant cost implications for voluntary organizations in terms of training and recruitment. The aim of this study was to identify the demographic, situational and motivational factors associated with burnout among buddies with the intention of identifying individuals at risk at the recruitment stage. A cross-sectional single cohort postal questionnaire study design was used. All buddies registered with the Terrence Higgins Trust, a non-profit making organization set up in the UK to provide education about HIV/AIDS and care for people affected by the virus, were invited to participate. Psychological morbidity was measured with the Hospital Anxiety and Depression Scale, burnout with the Maslach Burnout Inventory and motivation was assessed using the Calvert Motivation Checklist. Information on the buddy relationship and the demographic details of each buddy was also collected. Of 586 questionnaires distributed, 324 (55%) were returned. More than 24% of buddies were classified as probable cases of burnout on one or more of the MBI scales but this is lower than has been reported in medical and nursing staff working with people living with AIDS. Although a number of demographic, situational and motivational factors were associated with burnout, logistic regression models were unable to identify a useful proportion of individuals at risk. It was concluded that although burnout is an important psychological factor in retaining volunteers, it was not possible to identify individuals at risk of burning out either from their self-reported motivations or from demographic factors. 相似文献
995.
Semiconductor nanocrystals as fluorescent biological labels 总被引:4,自引:0,他引:4
M Bruchez M Moronne P Gin S Weiss AP Alivisatos 《Canadian Metallurgical Quarterly》1998,281(5385):2013-2016
Semiconductor nanocrystals were prepared for use as fluorescent probes in biological staining and diagnostics. Compared with conventional fluorophores, the nanocrystals have a narrow, tunable, symmetric emission spectrum and are photochemically stable. The advantages of the broad, continuous excitation spectrum were demonstrated in a dual-emission, single-excitation labeling experiment on mouse fibroblasts. These nanocrystal probes are thus complementary and in some cases may be superior to existing fluorophores. 相似文献
996.
VN Gorbunov AP Sytnik NN Korenev SA Gordeev EV Stoliarchuk GA Urzhumtseva 《Canadian Metallurgical Quarterly》1998,(9):14-17
Results of treatment of 1309 patients with perforated and bleeding pyloroduodenal ulcers for 20-years period have been analysed. Resection of the stomach performed in 85 cases resulted in high postoperative lethality which made up in bleeding ulcers 14.8%. Drainage operations of the stomach with excision or suturing of ulcer combined with bilateral truncal vagotomy was performed in 60 patients, postoperative lethality rate being 8.4%. 128 patients underwent selective proximal vagotomy together with pyloro- and duodenoplasty, lethality rate being 1.6%. Combined vagotomy (posterior truncal and anterior sero-muscular) with excision of ulcer, transversal pyloroplasty and duodenoplasty was carried out in 1036 patients (postoperative lethality--2.4%). Excellent and good functional results were achieved in 79.6% of the patients. 相似文献
997.
AP Théon 《Canadian Metallurgical Quarterly》1998,14(3):659-71, viii
This article covers the principles and applications of radiation therapy in horses. The goal in treating tumors by irradiation is tumor control with minimum treatment complications. Various treatment techniques are available to achieve this goal. The prognosis depends on many factors such as the extent and location of the tumor, tumor type and tumor cell proliferation. Radiation therapy is a very effective treatment modality for equine tumors but logistical reasons limit its impact in equine oncology. 相似文献
998.
E Brusamolino AP Anselmo C Klersy M Santoro E Orlandi G Pagnucco F Lunghi R Maurizi-Enrici CD Baroni M Lazzarino F Mandelli C Bernasconi 《Canadian Metallurgical Quarterly》1998,83(9):812-823
BACKGROUND AND OBJECTIVE: Patients treated for Hodgkin's disease have an increased risk of developing subsequent acute leukemia. This co-operative study was conducted to assess the relative risk associated with several candidate factors including age, splenectomy, combined modality therapy and cumulative drug dose including alkylating agents and nitrosurea derivatives. DESIGN AND METHODS: This study evaluated the risk of acute leukemia according to pretreatment variables and therapy modalities among 1659 patients treated for Hodgkin's disease and followed for a median time of 10 years. Both case-control and actuarial risk studies were performed. Median age was 34 years (range: 12-83); 53% of patients were splenectomized. As to the overall therapy, 348 patients (21%) were given radiotherapy (RT) alone, 375 (23%) chemotherapy (CT) alone (including MOPP, MOPP + ABVD or MOPP + ABVD + lomustine); 936 (56%) received both CT and RT, either as primary or salvage treatment. RESULTS: The overall 15-year actuarial risk of leukemia was 4.2%; the hazard function curve showed two peaks of risk at the 3th and the 8th year from the initiation of therapy and no leukemia beyond the 12th year of follow-up. Risk of leukemia was 0.3% after RT alone, 2.8% after CT alone (2.2% after MOPP; 4.4% after MOPP + ABVD + lomustine), and 5.4% in patients given combined modality therapy (10.2% for RT + MOPP; 15.6% for RT + MOPP + lomustine). No leukemia occurred after ABVD alone and the risk was low (0.6%) when neither mechlorethamine nor lomustine were utilized. Patients who had received extended radiotherapy including abdomen and pelvis in addition to MOPP showed a significantly higher risk of leukemia compared to those given limited RT + MOPP (P = 0.01). Case-control analysis indicated advanced stage, type and duration (> 8 months) of CT and extension of RT as significant risk factors for leukemia. Compared to RT alone, the odds ratio was 5.9 after MOPP + extended RT, and 8 when a lomustine-containing regimen was used, as well. Neither age nor splenectomy were independent risk factors for leukemia; splenectomy was influential only when patients had been given MOPP chemotherapy, as well. INTERPRETATIONS AND CONCLUSIONS: Both case-control and actuarial analyses indicated that: a) combined modality therapy with MOPP and extensive RT (including abdomen and pelvis), and the use of lomustine added to the leukemogenic risk of MOPP alone; b) programs without mechlorethamine, procarbazine and lomustine were almost devoid of leukemogenic risk. 相似文献
999.
AP Andonopoulos J Christodoulou C Ballas A Bounas D Alexopoulos 《Canadian Metallurgical Quarterly》1998,25(12):2385-2388
OBJECTIVE: To test patients with primary Sj?gren's syndrome (SS) for evidence of autonomic neuropathy. METHODS: Thirty-two patients with primary SS and 22 age and sex matched healthy individuals were asked specific questions about symptoms suggestive of autonomic neuropathy, and were subjected to a battery of 5 cardiovascular tests: response of blood pressure to sustained hand grip, Valsalva maneuver, heart rate response to deep breathing, and heart rate and blood pressure response to standing up. The chi-squared test with Yates' correction and 95% confidence intervals were used for statistical analysis of the results. RESULTS: Sixteen patients (50%) had symptoms of autonomic neuropathy when specifically asked versus none of the controls (p < 0.0005). The frequency of abnormal responses to the tests was 68.8% in patients and 12.7% in controls (p < 0.0001). Severe autonomic cardiovascular neuropathy was found in 87.5% of the patients but in none of the healthy individuals (p < 0.0001). CONCLUSION: Our results suggest that autonomic neuropathy is a feature of a significant portion of the SS population, and such patients should have appropriate evaluation. Similarly, patients with unexplained autonomic neuropathy should be investigated for evidence of SS. 相似文献
1000.