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51.
The nose and the lungs are anatomically and physiologically divided which lead to separated strategies in diagnostic and therapy. The upper airways, from the nose and lungs may account for the traditional division in upper and lower airways. Nonetheless a link between upper and lower respiratory tracts has been repeatedly observed in the past decades making the current division in two separate entities an arbitrary dichotomy. Once allergic rhinitis and asthma are two manifestation of the atopic syndrome it is logical to expect that allergy is not a disease confined to specific target organ rather to a broad spectrum of clinical manifestations. This hypothesis has been supported from various observations: Both, allergic asthma and allergic rhinitis are characterized by a similar if not an identical inflammatory process in which mast cells and eosinophils appear to be the major effector cells, high comorbidity of both allergic manifestations as shown in epidemiologic studies. Both diseases are caused by the interaction of genetic susceptibility with environmental factors. In this review, the latest developments in epidemiology and pathophysiology with regard to nasobronchial interaction in allergic airway disease will be discussed.  相似文献   
52.
53.
BACKGROUND: Due to perceived advantages in the use of non-ionic contrast agents for diagnostic angiography and ionic agents for percutaneous coronary intervention (PCI), patients often receive various combinations of both types of agents. AIM: To assess potential adverse effects of non-ionic and ionic contrast media when used together or separately during percutaneous coronary intervention. METHODS: We retrospectively evaluated the outcomes of 532 patients undergoing percutaneous coronary intervention in our institution. Patients were divided into two groups: those that underwent diagnostic angiography and "follow on" PCI; and those that underwent "planned" PCI. The groups were subdivided on the basis of the use of the ionic agent ioxaglate or the non-ionic agent iopromide during PCI. The frequency of allergic reactions and major adverse cardiac events (MACE) were noted. RESULTS: With respect to the "follow on" group, allergic reactions occurred in 9 of 150 patients (6.0%) who received the combination of ioxaglate and iopromide versus 1 of 93 (1.1%) who only received iopromide (p=0.094). There was no difference with respect to MACE [6 (4.0%) ioxaglate and iopromide versus 4 (4.3%) iopromide alone, p=1.00]. In the "planned" group, 7 of 165 patients (4.2%) receiving ioxaglate had an allergic reaction as opposed 0.0% (0 of 124 patients) in the iopromide group (p=0.021). All contrast reactions were mild. The incidence of a MACE was similar in both groups [1 (0.6%) ioxaglate versus 2 (1.6%) iopromide, p=0.579]. The incidence of allergic reactions was similar if ioxaglate was used alone or in combination with iopromide (p=0.478). CONCLUSIONS: Whilst combining ionic and non-ionic contrast agents in the same procedure was not associated with any more adverse reactions than using an ionic contrast agent alone, the ionic contrast agent ioxaglate was associated with the majority of allergic reactions. With respect to choice of contrast agent, using the non-ionic agent iopromide alone for coronary intervention is associated with the lowest risk of an adverse event.  相似文献   
54.
一氧化氮和一氧化氮合酶与肿瘤放疗敏感性的关系   总被引:1,自引:0,他引:1  
一氧化氮(nitricoxide,NO)的生物学作用具有复杂性和多样性,在基础条件下诱导型一氧化氮合酶(induciblenitricoxidesynthase,iNOS)活性很低,当机体遭受微生物内外毒素、炎症介质等刺激时iNOS可诱导合成大量的NO.肿瘤生物学上一般认为高水平的NO对肿瘤细胞具有直接的细胞毒作用,而较低水平的NO具有生长刺激作用.多种试验显示NO的供体能增加肿瘤的放疗敏感性.研究认为,NO的生物学作用可能是通过p53依赖途径介导的.调节NO杀灭肿瘤或促进肿瘤生长,p53起到关键性的作用.已有多种药品作为放射敏化剂,NO供体药物在体内给药可能导致系统低血压,增加肿瘤血液灌注和氧合作用,具有潜在的促进肿瘤生长的作用,限制了其临床使用.直接将iNOS基因转染入肿瘤细胞内,肿瘤内的乏氧环境,可降低iNOS的活性而影响NO的产量.携带iNOS基因的腺病毒(adenoviralvectorcarryingtheiNOScDNA,AdiNOS)转染靶细胞导致iNOS过表达,产生大量NO,有望成为一种增加肿瘤放疗敏感性有效可行的方法.  相似文献   
55.
Thrombophilic or haemorrhagic complications are possible adverse events following cardiac catheterization particularly in pediatric patients. It was therefore the aim of our study to compare the cardiac catheterization-related haemostatic changes in children with that in adults. The total of 50 patients was subdivided into Gr I (1–6 years), Gr II (7–18 years), and Gr III (19–58 years). Parameters of coagulation activation, plasma levels of various clotting factors and heparinase-modified thrombelastometry parameters were determined prior and immediately after cardiac catheterization. The haemostatic system of pediatric patients was markedly more affected by the procedure than that of adults. Levels of thrombin/antithrombin complex and prothrombin fragment 1+2 in the post-catheter plasma samples were significantly increased in Grs I and II, not in Gr III. The catheter-related decrease in fibrinogen and F II levels was higher in Gr I than in Grs II and III. F VII levels were significantly decreased in Grs I and II, not in Gr III. The catheter-related prolongation of Coagulation times was highest in Gr I, followed by Gr II and finally Gr III. A significant catheter-related decrease of maximum clot firmness was observed solely in Gr I. Our results show that cardiac catheterisation perturbs the haemostatic system of adults, and, even more pronounced, that of pediatric patients. Thus, our results indicate that children might be at a higher risk for either thrombotic complications or post-operative bleeding events than adults.  相似文献   
56.
射频毁损治疗肝脏肿瘤   总被引:12,自引:4,他引:12  
肝脏肿瘤包括肝原发性肿瘤和肝转移瘤,其治疗目前仍首选手术切除,但确诊时85%~95%的患者已失去手术切除时机,对难以手术治疗的患者已有多种介入治疗方法,如肝动脉栓塞化疗(TAE)、经皮无水酒精注射、微波、激光、冷冻、高功率超声聚焦等。射频毁损(radiofrequency ablation,RFA)是近年国外刚用于肝脏肿瘤治疗的新技术,具有安全性高、并发症少、患者易耐受、肿瘤复发可重复治疗等优点,具有良好的应用前景。 1 射频治疗仪及治疗机制 1868年法国的d'Arsonval发现高于10KHz的高变电流通过活体组织时,并不引起神经肌肉的应激,但局部产热造成组织毁损,自此射频毁损术在神经及心血管领域得以应用并  相似文献   
57.
The goal of this phase II multicenter clinical trial was to evaluate a new intensive chemotherapy program for adults with untreated acute lymphoblastic leukemia (ALL) and to examine prospectively the impact of clinical and biologic characteristics on the outcome. One hundred ninety-seven eligible and evaluable patients (16 to 80 years of age; median, 32 years of age) received cyclophosphamide, daunorubicin, vincristine, prednisone, and L-asparaginase; 167 patients (85%) achieved a complete remission (CR), 13 (7%) had refractory disease, and 17 (9%) died during induction. A higher CR rate was observed in younger patients (94% for those < 30 years old, 85% for those 30 to 59 years old, and 39% for those > or = 60 years old, P < .001) and in those who had a mediastinal mass (100%) or blasts with a T-cell immunophenotype. Eighty percent of B-lineage and 97% of T-cell ALL patients achieved a CR (P = .01). The coexpression of myeloid antigens did not affect the response rate or duration. Seventy percent of those with cytogenetic or molecular evidence of the Philadelphia (Ph) chromosome and 84% of those without such evidence achieved a CR (P = .11). Patients in remission received multiagent consolidation treatment, central nervous system prophylaxis, late intensification, and maintenance chemotherapy for a total of 24 months. After a median follow-up time of 43 months, the median survival for all 197 patients is 36 months; the median remission duration for the 167 CR patients is 29 months. Favorable pretreatment characteristics relative to remission duration or survival are younger age, the presence of a mediastinal mass or lymphadenopathy, a white blood cell count (WBC) less than 30,000/microL, L1 morphology, T or TMy immunophenotype, and the absence of the Ph chromosome. The estimates of the proportion surviving at 3 years are 69% for patients less than 30 years old, 39% for those 30 to 59 years old, 89% for those who had a mediastinal mass, 59% with WBC less than 30,000/microL, 63% with L1 morphology, 69% for T or TMy antigen expression, and 62% for those who lack the Ph chromosome. Fifteen patients (8%) had no unfavorable prognostic factors and have an estimated probability of survival at 5 years of 100% (95% confidence interval, 77% to 100%). This intensive chemotherapy regimen produces a high remission rate and a high proportion of durable remissions in adults with ALL.  相似文献   
58.
Ho  CP; Kim  RW; Schaffler  MB; Sartoris  DJ 《Radiology》1990,176(1):171-173
Dual-energy radiographic absorptiometry (DRA) was used to measure the bone mineral content and area density of lumbar vertebrae (L2-L3) in 11 cadavers. These data were subsequently compared with measured ash content and density. Excellent correlation was obtained between bone mineral content measured with DRA and ash weight (r = .963, P less than .0001). The accuracy error in determining mineral content in lumbar vertebrae with DRA was about 9%. In addition, strong correlation was observed between bone mineral density measured with DRA and ash density (r = .881, P less than .0001).  相似文献   
59.
Burns  CP 《Blood》1975,45(5):643-651
The metabolism of an essential amino acid, isoleucine, by human leukemic and gradient-separated normal human leukocytes of various types and maturity was studied. Blood leukocytes were isolated and incubated with (U-14C) isoleucine. Separation of metabolic intermediates was accomplished by sequential extraction. The rate of isoleucine incorporation into protein by immature cells from untreated patients with acute leukemia (15.9 plus or minus 2.4 nmoles/hr per 10-8 leukocytes) was considerably higher than the rates of incorporation by mature neutrophils (3.2 plus or minus 0.5 nmoles/hr per 10-8 leukocytes), lymphocytes (7.7 plus or minus 1.2 nmoles/hr per 10-8 leukocytes), and eosinophils (6.2 plus or minus 1.3 nmoles/hr per 10-8 leukocytes). Those cell preparations with more blast cells had higher rates of protein synthesis. In addition, those cells with greater thymidine incorporation had higher rates of protein synthesis. The leukocytes both oxidized isoleucine and incorporated it into cell isoleucine and incorporated it into cell lipid. The rates of these metabolic processes were characteristic for various types and maturity of leukocytes. This study demonstrates a relationship of rate of protein synthesis to leukocyte immaturity. This relationship is maintained in neoplastic leukocytes. It suggests that the requirement of the mitotic process for newly synthesized protein is greater than that for the elaboration of the protein products of the mature leukocyte.  相似文献   
60.
Aim:  To perform a 10-year follow up of cardiac structure and function after twin-to-twin transfusion syndrome (TTTS) – a severe foetal circulatory complication associated with myocardial hypertrophy in the recipient twin.
Methods:  Cardiac dimensions, systolic and diastolic function as assessed by echocardiography including flow and tissue Doppler velocimetry in 22 healthy survivors of TTTS with a mean age of 9.6 (7.2–11.8) years.
Results:  The donor and recipient twin did not show any differences in end-diastolic ventricular size, interventricular septum thickness, diameter of right ventricular outflow tract, cardiac valves, coronary arteries or in systolic blood flow velocities. However, compared with the donors, the recipients had significantly lower E/A ratios because of lower E-waves in both mitral (−0.15 ± 0.10, p < 0.01) and tricuspid (−0.09 ± 0.07, p < 0.01) valves, indicating reduced early diastolic ventricular fillings compared with donors.
Conclusion:  At school age, twins surviving TTTS had a cardiac structure and function within normal range. There were no differences in heart structure or systolic ventricular function between twins but, compared with the donor twin, we found a reduced early diastolic function in the recipient.  相似文献   
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