首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
The glycophorin A (GPA) somatic cell mutation assay is being applied widely as an in vivo biomarker in molecular epidemiologic studies of human populations. The assay uses two-color immunolabeling and flow cytometry of peripheral blood samples to enumerate allele-loss variant erythrocytes that appear as a result of mutations at the GPA locus in bone marrow erythroid cells. We have developed an improved version of the assay in which both anti-GPA monoclonal antibodies are directly conjugated with distinguishable fluorophores, fluorescein and phycoerythrin. Parallel analyses of 77 blood samples using the existing BR6 assay and our new DB6 assay demonstrate that the DB6 assay produces cleaner bivariate flow histograms with generally lower variant cell frequencies and lower coefficients of variation on replicate analyses of individual blood samples. With the BR6 assay, an artifact was shown to exist that results in enumeration of high frequencies of variant erythrocytes in a small fraction of samples that have been subjected to poor shipping and/or storage conditions. Using DB6, these same samples display acceptable histograms and low frequency of variant cells. High speed cell sorting followed by immuno analysis indicates that the BR6 artifact results from inhibited binding of the very high molecular weight antibody plus secondary reagent, which is used for the BR6 assay. We therefore recommend that DB6 be adopted as standard protocol for the GPA assay, and to assist other researchers in standardization and comparison, we are making available a set of calibrated, fixed blood samples.  相似文献   

2.
We have developed a new aortic prosthesis with which we can replace or reinforce the aorta using a simple percutaneous technique. We have named the new prosthesis the shape-memory aortic prosthesis (SAP); it consists of a spiral-shaped nitinol stent and polyurethane tube. It can be compressed inside a 14F catheter at a low temperature and regain its original shape at above 30 degrees C. As a preliminary study, SAP sutureless grafting into the descending aorta was performed on 10 mongrel dogs. We found that when the proper diameter of SAP was applied, it functioned satisfactorily for 3 months or more. A percutaneous placement technique pertinent to the SAP also was developed and tried on 4 animals. Our procedure was applied to Stanford type B dissection models to close the entry point successfully. This newly developed SAP has potential to be applied to emergency cases of human aortic dissections.  相似文献   

3.
4.
The presence of a cardiodepressant factor of pancreatic origin has been reported in the plasma of experimental animals and man in a variety of shock states. It has been suggested that the depression of developed tension of the isolated cat papillary muscle may be caused by excess NaCl in the bathing medium rather than a specific cardiodepressant peptide. Incubated pancreatic homogenate was used as a source of this factor, and after protein precipitation, ultrafiltration (10,00 and 1,000 MW), dialysis and lyophilization, the residue was applied to a Sephadex G-10 column in order to ensure the removal of all salts. The protein effluent of the Sephadex column contained all the cardiodepressant activity of the filtered, dialyzed pancreatic homogenate and none of the salt content. To further isolate this cardiodepressant factor, the active residue was applied to a cellulose column and eluted with butanol: glacial acetic acid: water (25:26 v/v/v). This elution gave 8 distinct peptide peaks, one of which, peak 4, contained significant depressant activity. Thus, a cardiodepressant peptide of approximately 250-1,000 MW exists in pancreatic homogenates and this compound is not excess NaCl in the assay system.  相似文献   

5.
6.
7.
Aortic root abscess, aneurysm of sinus Valsalva, severe aortic valve insufficiency, and a fragile aortic wall caused by infective endocarditis were found in a 10-year-old child. Aortic valve replacement was intended as a preoperative strategy, but one of modifications of Cabrol had to be used urgently because of aortic root rupture between right atrial and aortic connection just after pericardiotomy.  相似文献   

8.
AIM: To compare the peroperative blood loss and the postoperative systemic inflammatory reaction in patients receiving either a Vasculour II Albumin pre-impregnated prosthesis (VA group, n = 32) or a preclotted Vasculour II prosthesis (V group, n = 33) for elective surgery of the abdominal aorta. SETTING: University Hospital. DESIGN: Prospective, randomised study. METHODS: Peroperative blood loss was measured over two different periods: Phase I from the beginning of the operation to the completion of the proximal anastomosis, when blood loss cannot be related to the model of prosthesis implanted and phase II after the completion of the proximal anastomosis to the end of the operation. Postoperative blood loss was evaluated by the determination of the retroperitoneal drainage volume over a period of 2 days immediately following the operation. The presence of periprosthetic fluid was measured with echography at days 4, 9, 30 and 60. The postoperative systemic inflammatory reaction was evaluated by measuring the sedimentation rate and the C reactive protein levels daily from day 1 to day 9, and at days 14, 21, 28, 45, and 60, and by measuring the body temperature daily from day 1 to day 9. RESULTS: No significant differences of peroperative blood loss were observed. The same proportion of patients (35%) in both groups received homologous transfusion. The mean number of units of homologous blood transfused per patient was respectively 0.77 and 0.91 for the VA and the V group. The retroperitoneal drainage volume and the percentage of patients with periprosthetic fluid did not differ significantly. No significant differences in systemic postoperative inflammatory reaction were observed. CONCLUSION: There were no benefits in using albumin-impregnated prosthesis as opposed to preclotted prosthesis in terms of peroperative and postoperative blood loss, or by looking at the incidence of homologous blood transfusion. However, the glutaraldehyde cross-linked albumin did not induce any systemic inflammatory reaction.  相似文献   

9.
Myospherulosis is a rare condition. The authors report a unique case of this entity arising in paranasal sinus. The review of literature with emphasis on pathogenesis is also discussed.  相似文献   

10.
There is no single standardized method of repair for the anatomic variations in aortic root pathology, which may include dissection, aneurysmal dilation, and valve disease and can occur at the annulus, sinuses of Valsalva, or the sinotubular junction. Composite valve/graft replacement, valve resuspension, and allograft each play a significant role in aortic root therapy, but none is applicable in all cases. Patient age, Marfan's syndrome, endocarditis, and previous valve replacement are examples of some of the wide variations in delineating factors.  相似文献   

11.
A 47-year-old man presented with hemoptysis. From around June 20, 1995, he had symptoms of a common cold, but hemoptysis suddenly occurred on July 1 and he was brought to hospital. The chest X-ray film showed pleural effusion and enlargement of the mediastinum. CT scans showed calcification of the aorta, with a pseudoaneurysm 8 cm in diameter anterior to the descending aorta. When thoracotomy was performed under partial extracorporeal circulation, the thoracic cavity was found to be filled with bloody hydrothorax and hematoma, and the lower lobe of the left lung was adherent to the descending aorta. After a longitudinal incision was made in the aorta, a perforation 7 mm in diameter was identified in the posterior wall, and this was assumed to be the cause of the pseudoaneurysm. This part of the aorta was replaced with a Woven Dacron graft. Takayasu's arteritis was diagnosed by histological examination of the resected specimen, and the changes in the aortic wall at the site of perforation were considered to be chronic. About 30% of patients with this disease have aortic ectasia, but only a few pseudoaneurysms have been reported. Since the pseudoaneurysm occurred in our patient after reduction in the dose of medication, the development of perforation was suggested to be related to this change. In the future, this patient will require careful follow up for anastomotic aneurysm.  相似文献   

12.
Propionibacterium acnes is often considered to be a contaminant but it has also been found to be the principal pathogen in serious infections. P. acnes is a rare cause of infective endocarditis. It has been suggested that aortic root abscesses are caused by bacteria that are particularly virulent. The strongest risk factor for serious infections by this bacteria is the presence of foreign bodies. A case is presented in which endocarditis of a native aortic valve caused by P. acnes was associated with an aortic root abscess. Transesophageal echocardiography is particularly helpful in the diagnosis of this severe complication of infective endocarditis. The literature for P. acnes endocarditis is reviewed.  相似文献   

13.
In recent years several researchers have suggested that the changes in the geometry and angular dimensions of the aortic root which occur during the cardiac cycle are functional to the optimisation of aortic valve function, both in terms of diminishing leaflet stresses and of fluid-dynamic behaviour. The paper presents an analytical parametric model of the aortic valve which includes the aortic root movement. The indexes used to evaluate the valve behaviour are the circumferential membrane stress and the stress at the free edge of the leaflet, the index of bending strain, the bending of the leaflet at the line attachment in the radial and circumferential directions and the shape of the conduit formed by the leaflets during systole. In order to evaluate the role of geometric changes in valve performance, two control cases were considered, with different reference geometric configuration, where the movement of the aortic root was ignored. The results obtained appear consistent with physiological data, especially with regard to the late diastolic phase and the early ejection phase, and put in evidence the role of the aortic root movement in the improvement of valve behaviour.  相似文献   

14.
BACKGROUND: Endoscopic diagnosis of short segments of Barrett's epithelium (SSBE)' is difficult and its meaning in terms of the presence of specialised columnar epithelium (SCE) has not been prospectively evaluated. AIMS: To evaluate the prevalence of SCE in patients with an endoscopic diagnosis of SSBE and in individuals with normal appearing oesophagogastric junctions, and to compare the clinical characteristics of these two groups. PATIENTS: Thirty one patients with an endoscopic diagnosis of short Barrett's oesophagus, less than 3 cm in length (group A), and 44 consecutive patients with normal appearing oesophagogastric junctions (group B). METHODS: Multiple biopsies were performed in suspicious epithelium and at the oesophagogastric junction in groups A and B, respectively. RESULTS: Age and sex distribution were similar in both groups. Reflux symptoms were more frequent in group A (p < 0.001), as were endoscopic and histological signs of oesophagitis (p < 0.001 and p = 0.001, respectively). SCE was found in 61.3% of group A patients compared with 25% in group B (p < 0.002), with men predominating in group A while women were more frequent in group B (p = 0.02). The differences in reflux symptoms and endoscopic/histological oesophagitis remained significant. CONCLUSIONS: These results show that endoscopic diagnosis of SSBE is associated with a high prevalence of SCE, significantly higher than that found in normal appearing oesophagogastric junctions. Differences between patients with SCE in the two groups suggest they may represent two different entities.  相似文献   

15.
We used a Freestyle (Medtronic, Minneapolis, MN) porcine root to replace a regurgitant aortic valve and repair acute type A dissection. A Hemashield (Meadox Medicals, Oakland, NJ) graft was used to replace the ascending aorta with the "open anastomosis" technique. This method is a valuable alternative to conventional root replacement in acute type A dissection.  相似文献   

16.
The present article endeavours an outline of depressive delusions, their symptomatology and their various topics. Their relations to depressive feelings of guilt and anxiety are discussed and differentiated. Delusions of guilt, poverty or disease including their preliminary states are by no means rare but regularly occurring symptoms which substantiate the diagnosis of major depressive disorder/endogenous depression/melancholia. Preliminary states like hypochondriatic fears of guilt and poverty are likewise characteristic clinical signs which may be differentiated with high validity from the kind of anxiety associated to neurotic depression/dysthmia. Delusional depression did not prove to be a nosological entity but as a concept may bear considerable heuristic value concerning therapeutic considerations. This particularly serious form of depression requires specific therapeutic procedures.  相似文献   

17.
A 55-year-old lady underwent repeat aortic valve replacement using a 16-mm Carbomedics prosthesis. She made an uneventful postoperative recovery and now leads an unrestricted life. Doppler echocardiography reveals a 21-mm Hg gradient across the valve at rest. This did not increase with an infusion of 30 mcg/kg per min of dobutamine, which resulted in an increase in the cardiac output from 1.96 to 5.46 l/min.  相似文献   

18.
CONTEXT: Motor vehicle crashes continue to cause significant mortality and morbidity in the United States. Installation of air bags in new passenger vehicles is a major initiative in the field of injury prevention. OBJECTIVE: To assess the net health consequences and cost-effectiveness of driver's side and front passenger air bags from a societal perspective, taking into account the increased risk to children who occupy the front passenger seat and the diminished effectiveness for older adults. DESIGN: A deterministic state transition model tracked a hypothetical cohort of new vehicles over a 20-year period for 3 strategies: (1) installation of safety belts, (2) installation of driver's side air bags in addition to safety belts, and (3) installation of front passenger air bags in addition to safety belts and driver's side air bags. Changes in health outcomes, valued in terms of quality-adjusted life-years (QALYs) and costs (in 1993 dollars), were projected following the recommendations of the Panel on Cost-effectiveness in Health and Medicine. PARTICIPANTS: US population-based and convenience sample data were used. MAIN OUTCOME MEASURE: Incremental cost-effectiveness ratios. RESULTS: Safety belts are cost saving, even at 50% use. The addition of driver's side air bags to safety belts results in net health benefits at an incremental cost of $24000 per QALY saved. The further addition of front passenger air bags results in an incremental net benefit at a higher incremental cost of $61000 per QALY saved. Results were sensitive to the unit cost of air bag systems, their effectiveness, baseline fatality rates, the ratio of injuries to fatalities, and the real discount rate. CONCLUSIONS: Both air bag systems save life-years at costs that are comparable to many medical and public health practices. Immediate steps can be taken to enhance the cost-effectiveness of front passenger air bags, such as moving children to the rear seat.  相似文献   

19.
Hydrops fetalis is rarely associated with congestive heart failure caused by obstructive left-sided heart lesions. There are rare cases of live born neonates with critical congenital valvar aortic stenosis and hydrops reported in the literature, all with fatal outcomes. This report describes, to the best of our knowledge, the first two newborns who were diagnosed prenatally to have hydrops fetalis caused by critical valvar aortic stenosis, who were treated prenatally with digoxin and who postnatally had successful percutaneous balloon aortic valvuloplasty. Both patients had not only left but right ventricular dysfunction. We speculate that right ventricular dysfunction was a contributing factor in the development of hydrops in these patients and in utero medical therapy with digoxin is associated with resolution of the hydrops before delivery.  相似文献   

20.
This is the first report of a schwannoma originating from the C7 nerve root causing thoracic outlet compression syndrome. The patient was a 30-year-old woman with a 3-year history of numbness on the radial side of the left hand, left arm tiredness, nocturnal pain in the left forearm and pain in the left elbow, shoulder and neck. Conservative treatment and previous operations, including carpal tunnel release and first rib resection, provided no relief. A left scalenectomy was performed. During the removal of the anterior scalene muscle, a mass approximately 3 cm long and 1.5 cm in diameter was noted under the anterior scalene muscle involving the C7 nerve root. The tumour was encapsulated and covered with attenuated and stretched nerve fascicles. It was completely excised without disturbing the nerve fascicles. The clinical impression was schwannoma, which was confirmed on pathological examination.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号