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51.
Kissel A Rixe O Methlin A Nabet M Tranquart F Rubini B Jafaar S Gaucher H 《Journal de radiologie》2001,82(11):1621-1625
PURPOSE: To quantify liver blood flow using US contrast agents and to evaluate arterial and portal changes in control patients and patients with liver metastases. MATERIALS AND METHODS: Twenty eight patients were included in this study, 8 controls (M0) and 20 patients with liver metastases from colon carcinoma (M+). Hepatic blood flow from hepatic artery and portal vein were determined using quantification of enhancement after contrast injection using Power Doppler US. The ratio of enhancement rise from artery and vein allows calculation of Contrast Enhanced Doppler Perfusion Index (CEDPI) as previously described for Doppler Perfusion Index (DPI). RESULTS: A significant difference was noted for CEDPI between controls (0.49 +/- 0.07) and liver with metastases (0.70 +/- 0.12). CONCLUSION: This functional method of evaluation of liver blood flow was easy to perform, and would be valuable for early detection of overt micro-metastases before anatomical changes observed by conventional imaging. This is helpful for accurate staging of colon carcinoma. 相似文献
52.
Warty carcinoma of the oral mucosa in an HIV+ patient 总被引:1,自引:0,他引:1
The authors present the case of a 36-year-old HIV+ male patient with a 1-cm diameter papillary exophytic lesion of the right cheek. Microscopic examination showed a papillary epithelial neoplasm with invasion of the stroma in the peripheral part. Cellular and nuclear atypia were present in the superficial and in the deep layers of the neoplasm. An in situ hybridization for human papillomavirus (HPV) 6, 11, 16, 18, 31, 35 and 51 was performed. A focal positivity only for HPV 16 and 18 was present in koilocytotic cells of the most peripheral portion of the lesion. The microscopic definitive diagnosis was warty carcinoma of the cheek. No recurrence was observed at a 3-year follow-up. 相似文献
53.
Angiomyolipoma (AML) is a tumour or an hamartomatous growth that usually affects the kidney. Only rarely has AML been described in the oral cavity. The authors report a case of AML located in the palate in a 43-year-old patient. AML is composed of smooth muscle cells, blood vessels and mature fat cells. In 50% of cases, AML presents with symptoms of tuberous sclerosis. Renal AML are often invasive, may involve regional nodes and may recur, while, on the contrary, AML are most often well circumscribed and easily resected. AML seems to follow an entire benign course. 相似文献
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Mixed lymphocyte reactivity and cell-mediated lympholysis to trinitrophenyl-modified autologous lymphocytes in C57BL/10 congenic and B10.A recombinant mouse strains 下载免费PDF全文
GM Shearer EC Lozner TG Rehn A Schmitt-Verhulst 《The Journal of experimental medicine》1975,141(4):930-934
Cell-mediated lympholysis (CML) to trinitrophenyl (TNP)-modified autologous splenic lymphocytes has been recently reported in the mouse (1). Both the sensitization and effector phases of this phenomenon were shown to be T-cell mediated. Effector cell specificity studies indicated that modification of the target cells is a necessary but insufficient requirement for cytolysis, and suggested that altered cell surface components controlled by genes mapping in the mouse major histocompatibility H-2 complex (MHC) are important in the specificity of the cytotoxic reaction (1). In allogeneic models the generation of cytotoxic effector cells has been shown to be preceded or accompanied by immunogen- induced proliferation of responding lymphocytes, i.e. a mixed lymphocyte reaction (MLR) (2-5), although the generation of effectors may not necessarily always be the consequence of extensive cell proliferation (5). If the induction of cytotoxic effector lymphocytes by modified syngeneic spleen cells is characteristic of sensitization with cellular alloantigens, one would expect to find that sensitization with TNP-modified autologous cells would also induce thymidine incorporation by the responding cells in the culture. The present report demonstrates that both stimulation of thymidine incorporation and generation of cytotoxic effector cells are part of the in vitro response to TNP-modified autologous lymphocytes. However, the MLR to TNP- modified autologous cells consistently appeared to be less pronounced when compared with an allogeneic MLR, whereas the cytotoxic activity of the effector cells generated by sensitization against TNP-modified autologous cells was frequently as high as that detected against H-2 alloantigens. These two components of reactivity to “modified self” are verified in several C57BL/10 congenic and B10.A recombinant mouse strains. 相似文献
57.
JB Gorlin ; EC Vamvakas ; E Cooke ; D Galacki ; R Geha ; D Humphreys ; P Kent 《Transfusion》1996,36(10):879-885
Background: Recruitment of progenitors during a large-volume collection, as defined by increasing relative and absolute numbers of progenitors (colony-forming units-granulocyte-macrophage [CFU-GM] of CD34+ cells), has been reported previously. Study Design and Methods: To ascertain whether intra-apheresis recruitment occurs in pediatric patients who have undergone mobilization with chemotherapy and granulocyte-colony-stimulating factor (G-CSF), each hour's portion of a 4-hour leukapheresis was collected into separate bags, and assessed by complete blood count, CFU-GM, and CD34+ cell assays. Seven pediatric patients (median age, 7; range, 2–19) were studied in connection with 2 to 4 collections each, for a total of 21 collections (with hourly samples). The collections lasted for 4 hours, at an inlet rate of 1 to 3 mL per kg per minute, for daily processing totals of 5 to 12 blood volumes. (One blood volume [mL] is estimated by the patient's weight in kg × 70 mL/kg.) Smaller (younger) patients had inlet rates exceeding 2 mL per kg per minute, and larger (older) patients had rates of 1 to 1.5 mL per kg per minute. CFU-GM and CD34+ cell counts obtained each hour of the collection and divided by the first hour's value were compared by nonparametric repeated-measures ANOVA. Results: Second-, third- and fourth-hour CD34+ progenitor cell counts were arithmetically higher than first-hour counts, but the trend did not reach significance (p = 0.1561). Second-hour counts were higher than first-hour counts in the overall analysis (mean ± standard error [SE], 1.00 and 1.39 ± 0.1, respectively; p = 0.0525) and in children older than 5 years (1.00 vs. 1.70 ± 0.30, respectively; p = 0.0259), but not in children younger than 5 years (p = 0.8125). CFU-GM counts did not differ among the 4 hours of collection (p = 0.1717) or between the first and second hour (p = 0.9587). Conclusion: In larger (older) patients, from whom fewer blood volumes were collected, there is a trend toward intra-apheresis recruitment, although less than reported previously. In the smaller (younger) patients, from whom more blood volumes were collected, no trend was observed. Lack of (or submaximal) prior mobilization in previously reported studies may have facilitated intracollection recruitment. Alternatively, the larger number of blood volumes collected from the smaller (younger) patients may have masked intra-apheresis recruitment. The study documents the feasibility of large-volume, 4-hour leukapheresis in pediatric patients. 相似文献
58.
E. Zanotti F. Rubini G. Iotti A. Braschi A. Palo C. Bruschi C. Fracchia S. Nava 《Intensive care medicine》1995,21(5):399-405
Objective To assess in a group of COPD patients mechanically ventilated for an episode of acute respiratory failure the respiratory mechanics with a simple and non invasive method at the bedside in order to evaluate if these parameters may be predictive of weaning failure or success.Design A prospective study.Setting Intensive care and intermediate intensive care units.Patients 23 COPD patients ventilated for acute respiratory failure and studied within 24 hours from intubation.Methods Using end-expiratory and end-inspiratory airway occlusion technique, we measured PEEPi, static compliance of the respiratory system (Crs, st) maximum respiratory resistance (Rrsmax) and minimum respiratory resistance (Rrsmin).Measurements and results The weaned group (A) and the not weaned group (B) were not different regarding to static PEEPi (group A 8.5±4.0 vs group B 8.9±2.6 cmH2O), to Rrsmax (22.4±5.3 versus 22.2±9.0 cmH2O/l/s) and to Rrsmin (17.6±5.5 versus 17.9±8.0 cmH2O/l/s), while a significant difference (p<0.001) has been found in Cst, rs (62.7±17.5 versus 111.6±18.0 ml/cm H2O). The threshold value of 88.5 ml/cmH2O was identified by discriminant analysis and provided the best separation between the two groups, with a sensitivity of 0.85 and a specificity of 0.87.Conclusion Cst, rs measured non invasively in the first 24 h from intubation, provided a good separation between the patients who were successfully weaned and those who failed. 相似文献
59.
Changes in the practice of non-invasive ventilation in treating COPD patients over 8 years 总被引:4,自引:0,他引:4
OBJECTIVE: We reviewed data of 208 episodes of acute respiratory failure due to chronic obstructive pulmonary disease treated by non-invasive ventilation (NIV) in our Respiratory Intensive Care Unit (RICU) from its opening in 1992 to 1999. MATERIAL AND METHODS: We assessed whether the rate of NIV success, the severity of the disease, and the associated costs changed in this period during which the staff and the equipment did not change. RESULTS: The failure rate was constant over the years (17.2% on average). The severity of the episodes of ARF, defined by pH and APACHE II at admission, worsened during the years. The statistical change point test allowed us to identify 1997 as the year of a significant change in the severity of admission pH and therefore to identify two different periods: 1992-1996 (mean pH = 7.25+/-0.07) and 1997-1999 (7.20+/-0.08; P<0.001). In this latter period the risk of failure for a patient with a pH <7.25 was threefold lower than in 1992-1996. In 1997-1999 an increasing number of episodes of ARF with a pH >7.28 were treated in the Medical Ward (20% vs 60%). This allowed a significant reduction of daily cost per patient treated with NIV (558+/-8 Euros vs 470+/-14 Euros, respectively; P<0.01). CONCLUSIONS: We conclude that, over time, experience with NIV may progressively allow more severely ill patients to be treated without changing the rate of success. The daily cost of NIV per patient can be reduced by treating less severely ill patients outside the RICU. 相似文献
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