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701.
Kaouther Snoussi Wijden Mahfoudh Noureddine Bouaouina Meriem Fekih Hedi Khairi Ahmed N Helal Lotfi Chouchane 《BMC cancer》2010,10(1):283
Background
Interleukin-8 (IL-8/CXCL-8) is a prototype of the ELR+CXC chemokines that play an important role in the promotion and progression of many human cancers including breast cancer. We have recently showed the implication of polymorphism (-251) T/A of IL-8 gene in the susceptibility and prognosis of breast carcinoma. IL-8 acts through its CXCR1 and CXCR2 receptors. CXCR2, expressed on the endothelial cells, is the receptor involved in mediating the angiogenic effects of ELR+CXC chemokines and in particular IL-8. 相似文献702.
Background
In the US, foreign-born Hispanics tend to live in socioeconomic conditions typically associated with later stage of breast cancer diagnosis, yet they have lower breast cancer mortality rates than their US-born counterparts. We evaluated the impact of nativity (US- versus foreign-born), neighborhood socioeconomic status (SES) and Hispanic enclave (neighborhoods with high proportions of Hispanics or Hispanic immigrants) on breast cancer stage at diagnosis and survival among Hispanics. 相似文献703.
Relationship between endotracheal tube leakage and under-reading of tidal volume in neonatal ventilators 总被引:1,自引:0,他引:1
RA Mahmoud HS Fischer H Proquitté HM Abudaif Shalaby G Schmalisch 《Acta paediatrica (Oslo, Norway : 1992)》2009,98(7):1116-1122
Aim: Protective ventilation in neonates requires careful volume monitoring to prevent ventilator-induced lung injury caused by baro/volutrauma and hence chronic lung disease. This study investigated the effect of endotracheal tube (ET) leakage on the displayed tidal volume using an in vitro model.
Methods: A neonatal lung model was ventilated via a 3 mm ET using three ventilators [Babylog 8000 (BL), Leoni (LE) and Stephanie (ST)]. Tidal volume was measured by each ventilator at the Y-piece and by a pneumotach (CO2 SMO+ ) in the model. ET leaks were simulated by open tubes of different lengths. PIP (20 cmH2 O) and PEEP (5 cmH2 O) were kept constant, and the respiratory rate (RR) was varied between 20/min and 70/min (Ti:Te = 1:1).
Results: Tidal volume displayed by a ventilator decreased independently of RR with increasing leakage up to 21% (BL), 30% (LE) and 33% (ST). However, the volume delivered to the lung was nearly constant. The displayed leakage varied between 0 and 78% and was dependent on RR and leakage resistance. There were distinct differences between the three ventilators in the relationship between displayed leakage and volume error. Accepting a volume error <10% for RR between 20 and 70/min, ET leakage of up to 20% for BL, 12% for LE, but only <5% for ST, was acceptable.
Conclusion: Tidal volume underestimation arising from ET leakage depends on ventilator pressures, timing parameters and ventilator-specific algorithms for signal processing. Therefore, neonatologists should be aware of these issues to prevent lung over-inflation when adjusting target volume in the presence of ET leakage. 相似文献
Methods: A neonatal lung model was ventilated via a 3 mm ET using three ventilators [Babylog 8000 (BL), Leoni (LE) and Stephanie (ST)]. Tidal volume was measured by each ventilator at the Y-piece and by a pneumotach (CO
Results: Tidal volume displayed by a ventilator decreased independently of RR with increasing leakage up to 21% (BL), 30% (LE) and 33% (ST). However, the volume delivered to the lung was nearly constant. The displayed leakage varied between 0 and 78% and was dependent on RR and leakage resistance. There were distinct differences between the three ventilators in the relationship between displayed leakage and volume error. Accepting a volume error <10% for RR between 20 and 70/min, ET leakage of up to 20% for BL, 12% for LE, but only <5% for ST, was acceptable.
Conclusion: Tidal volume underestimation arising from ET leakage depends on ventilator pressures, timing parameters and ventilator-specific algorithms for signal processing. Therefore, neonatologists should be aware of these issues to prevent lung over-inflation when adjusting target volume in the presence of ET leakage. 相似文献
704.
705.
Liesbeth Hameetman Judith VMG Bovée Antonie HM Taminiau Herman M Kroon Pancras CW Hogendoorn 《Hereditary cancer in clinical practice》2004,2(4):161-173
Multiple Osteochondromas is an autosomal dominant disorder characterised by the presence of multiple osteochondromas and a variety of orthopaedic deformities. Two genes causative of Multiple Osteochondromas, Exostosin-1 (EXT1) and Exostosin-2 (EXT2), have been identified, which act as tumour suppressor genes. Osteochondroma can progress towards its malignant counterpart, secondary peripheral chondrosarcoma and therefore adequate follow-up of Multiple Osteochondroma patients is important in order to detect malignant transformation early.This review summarizes the considerable recent basic scientific and clinical understanding resulting in a multi-step genetic model for peripheral cartilaginous tumorigenesis. This enabled us to suggest guidelines for clinical management of Multiple Osteochondroma patients. When a patient is suspected to have Multiple Osteochondroma, the radiologic documentation, histology and patient history have to be carefully reviewed, preferably by experts and if indicated for Multiple Osteochondromas, peripheral blood of the patient can be screened for germline mutations in either EXT1 or EXT2. After the Multiple Osteochondroma diagnosis is established and all tumours are identified, a regular follow-up including plain radiographs and base-line bone scan are recommended. 相似文献
706.
目的:合成依西美坦并改进合成工艺。方法:以雄甾烯一酮为原料,经Mannich反应、溴化、脱溴等数步反应制得依西美坦。结果:所得产物经元素分析。柴外光谱,红外光谱,核磁共振谱及质谱等确证了结构。结论:此路线是可行的。 相似文献
707.
Prostatic carcinoma: staging with MR imaging at 1.5 T 总被引:5,自引:0,他引:5
Bezzi M; Kressel HY; Allen KS; Schiebler ML; Altman HG; Wein AJ; Pollack HM 《Radiology》1988,169(2):339-346
Magnetic resonance (MR) imaging was used to stage prostatic carcinoma in 81 patients with a proved diagnosis. MR imaging findings were correlated with histologic findings regarding the local extent of disease (37 patieNts) and the presence of nodal metastases (51 patients). Tumor nodules were detected in the peripheral zone (PZ) in 34 of 37 patients and were of low signal intensity compared with the signal of the PZ. Hemorrhage in the PZ represented a problem in tumor detection and in tumor volume measurement. When multiple criteria for local tumor spread were combined, MR imaging had a sensitivity of 72%, a specificity of 84%, and an accuracy of 78% in the differentiation of stage A or B from Stage C or D disease. Assessment of seminal vesicle invasion was more accurate than assessment of direct extracapsular spread. In five patients, microscopic invasion of the capsule (stage C) was classified as stage B with MR imaging; from a clinical standpoint, this should not affect patient treatment and prognosis. The MR imaging sensitivity in the detection of lymph node metastases was 69%, with a specificity of 95% and an accuracy of 88%. In this study MR imaging proved reliable in the comprehensive evaluation and staging of prostatic carcinoma. 相似文献
708.
709.
During the procedures of centrifugation leukapheresis and plateletpheresis, donors occasionally experience adverse clinical reactions. The possibility of whether the activation of granulocytes and the subsequent release reactions, which may have been triggered by this extracorporeal circuit, were responsible for these adverse effects was evaluated. Six blood samples were obtained at set intervals during cytapheresis. Of these samples, four were taken directly from the donor. The remaining two were drawn from the efferent lines, i.e., those which return blood from the cytapheresis machine to the donor. Reactive oxygen species produced by granulocytes were measured by chemiluminescence (CL) using microamounts of whole blood or isolated granulocytes. Furthermore, secreted granulocyte products such as neutral proteinase elastase, which is present in plasma in a complex with alpha-1-proteinase inhibitor (E-alpha-1-PI), and lysosomal beta-glucuronidase were examined. A complete blood cell count and the values of hemoglobin, hematocrit, lactate dehydrogenase, protein, albumin, and proteinase inhibitors such as alpha-2-macroglobulin and alpha-1-proteinase inhibitor were also determined. Clinical chemical and cytologic values, with the exception of those for E-alpha-1-PI, were 10 to 17 percent lower than values before apheresis. These results can be attributed to inherent plasma volume expansion. Reduced CL was observed on the stimulation of phagocytes in the whole blood assay, as well as with stimulated granulocytes. Unstimulated granulocytes, on the other hand, showed an increased native CL. These data do not indicate a cytapheresis-mediated activation of the oxidative metabolism of granulocytes, and the concomitant discharge of proteolytic enzymes remains, therefore, of no clinical importance. 相似文献
710.
Six patients with calcified transitional cell carcinoma of the renal pelvis were encountered over a 10-year period, and the radiographic features in these cases are presented. Radiographically discernible calcification is one of the less common manifestations of this lesion, and the pattern of calcification may be variable. However, the combination of a coarse, punctate pattern with a mucosal lesion on excretory or retrograde urography should suggest the diagnosis and prompt further investigation. 相似文献