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1.
Episodes of hematuria in IgA nephropathy or Henoch-Sch?nlein purpura are frequently associated with microbial infections. Some of those infectious agents bear alpha-galactosyl residues on their cell surface. These observations prompted us to determine, by passive hemagglutination, the titers of natural anti-galactosyl antibodies in the serum of children presenting with Henoch-Sch?nlein purpura (10 cases) or IgA nephropathy (7 cases). Antibody titers of normal subjects (103 cases), children with a pharyngitis of unknown etiology (7 cases), and children exhibiting mesangial IgA deposits but no hematuria at the time of testing (6 cases) ranged from 1:20 to 1:80. Elevated titers (greater than 1:80) were observed in nine of 11 patients with mesangial IgA deposits and micro- or macroscopic hematuria, in nine of 19 children with other evolutive glomerular diseases (5 cases of acute glomerulonephritis and 4 cases of minimal change disease), and in most subjects presenting with a M. pneumoniae (4/5 cases) or a E. Coli (4/5 cases) infection. Antibody titers decreased after incubation of normal and pathological sera with D-galactose (10 mM) or with alpha-galactosyl-glucoside (10 mM), but not with D-glucose (10 mM). The anti-alpha-galactosyl antibodies purified, by affinity chromatography, from sera of 10 normal children, 10 pathological controls and four children with mesangial IgA deposits without hematuria belonged to IgG class. In contrast, both IgG and IgA anti-alpha-galactosyl antibodies were detected in six of six patients with mesangial IgA deposits and hematuria. The IgA content of immune complexes detected in those patients decreased after incubation of sera with alpha-galactosyl-glucoside, but not with D-glucose.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
2.
An enzyme-linked immunoassay has been recently set up for direct measurement of the binding capacity of plasma fibronectin to gelatin. This binding capacity could be completely inhibited in vitro by an eight-fold excess of gelatin, of Haemaccel, but not of Geloplasma. On the contrary, the levels of immunoreactive fibronectin measured by laser nephelometry did not change, in presence of 10 to 1000 micrograms ml-1 of gelatin, of Haemaccel or of Geloplasma. When infused into normal volunteers, Haemaccel provoked a strong and immediate inhibition of the plasma fibronectin binding capacity to gelatin. This inhibition was dose-dependent and maximal after infusion of 500 ml of Haemaccel. Twenty-four hours after this infusion, there was a progressive recovery of the gelatin-binding capacity, which was almost completely achieved 96 h later. The formation of complexes between Haemaccel and fibronectin was demonstrated by gel filtration chromatography and by affinity chromatography. Immunoreactive plasma fibronectin levels remained unchanged up to 24 h after infusion of 500 ml of Haemaccel. A transient decline to 50% of its initial value then occurred the second day after the infusion. Therefore, a delay existed between the formation of fibronectin-Haemaccel complexes and their elimination from the bloodstream. This delay decreased when smaller volumes of Haemaccel were infused, which strongly suggests that plasma fibronectin is cleared by means of Haemaccel and does not seem to play a role of opsonin in these conditions.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
3.
The influence of the length and origin of a small bowel graft on graft versus host disease (GVHD) was studied in 33 (Lewis x brown Norway) F1 hybrids transplanted with different types of Lewis small bowel grafts. Recipients of an entire small bowel graft (N = 9), a jejunal graft (N = 6), or an ileal graft (N = 6) displayed a similar acute lethal GVHD, with 100% mortality rate and equivalent survival time (15 +/- 0.7, 16.8 +/- 0.9, and 16 +/- 0.6 days, respectively) (P greater than 0.01). On the other hand, 80% of the recipients of a segmental jejunal graft (N = 10) recovered from a transitory form of GVHD and regained weight similarly to the isografted rats (N = 4). It was concluded that the entire small bowel, jejunum, and ileum can provoke an equivalent GVHD after transplantation, whereas a segment of jejunum decreases the intensity of GVHD, probably by reducing the amount of transplanted lymphoid tissue.  相似文献   
4.
A 15-month-old girl with rhinopharyngitis was treated with a nasal solution containing the imidazoline derivative naphazoline. She rapidly developed profound CNS depression with stupor, hypothermia, hypoventilation and bradycardia. All symptoms disappeared within 24 h. The symptomatology of 18 other paediatric cases of naphtylimidazoline exposure reported to the Belgian National Poison Centre, is also discussed. Imidazoline intoxication due to overdose or accidental ingestion but also after normal therapeutic usage is frequent in children. It can cause severe CNS depression, especially in very young children. For these reasons vasoconstrictor imidazoline containing solutions should be prescribed with caution and kept out of reach of children.  相似文献   
5.
BACKGROUND: The initial rate of plasma HIV-1 RNA (pVL) decline has been proposed as a marker of early efficacy of antiretroviral therapy (ART) and a possible predictor of late efficacy. We compared the rate of pVL decline in patients starting ART with nevirapine (NVP), efavirenz (EFV), or both drugs combined in addition to lamivudine (3TC) and stavudine (d4T). METHODS: Analysis of the viral decay constant (VDc) during the first 2 weeks of treatment in patients enrolled in the 2NN study who remained on allocated treatment. RESULTS: The median VDc (log10 copies per day, [interquartile range]) was similar for NVP (0.30 [0.25-0.36], EFV (0.31 [0.27-0.37]), and NVP + EFV (0.30 [0.27-0.36]). Patients with a baseline pVL >100,000 copies/mL were 8.7 (95% confidence interval [CI]: 6.2-12.3) times more likely to have a VDc >75th percentile. A high VDc was not associated with plasma drug concentration or with a decreased risk of virologic failure at week 48 after the start of therapy (hazard ratio = 0.8, 95% CI: 0.6-1.2). CONCLUSION: NVP, EFV, or NVP + EFV in combination with 3TC and d4T show similar rates of pVL decline during the first 2 weeks of treatment. The VDc with these regimens is not predictive of late virologic efficacy.  相似文献   
6.
A novel tracheal tissue connector for fixation of laryngeal prostheses   总被引:1,自引:0,他引:1  
A tissue connector (TC), basically consisting of a ring that will be integrated into the trachea, is under development to study the fixation of laryngeal prostheses. Two experiments have been performed to test the TC in goats. In experiment 1, a polypropylene mesh was implanted around the trachea. The meshes were explanted after 6 and 12 weeks. In experiment 2, the actual TC consisted of two titanium rings (inner ring and outer ring) executed as quarter rings, fixed on each other, and a polypropylene mesh like a sandwich in between. The titanium inner ring was implanted between two tracheal rings thus penetrating the trachea with the mesh around the trachea and the fixed titanium outer ring on the outside of the trachea. The TCs were removed after 12 weeks. Experiment 1 showed that the mesh was entirely infiltrated by host tissue. Inflammatory cells and high vascularisation were observed in 3 of 4 implants. However, in experiment 2, the mesh was completely incorporated by mature connective tissue without inflammation reaction. At some areas, deposition of cartilage tissue was observed. In conclusion, the TC was firmly embedded in the trachea thus being appropriate for its intended use.  相似文献   
7.
Objective. The European Eureka project ‘Artificial larynx’ aims at realizing an implantable artificial larynx, consisting of artificial vocal folds, artificial epiglottis, tissue connector for tracheal fixation and valve mechanism to switch between breathing and speaking. The last part has been realized. Because its functioning is identical to a tracheostomal valve, it was tested as such. Materials and methods. The device consists of two valves: a speech valve, that will be open during normal breathing and closed by strong expiration and a cough valve that opens during coughing and closes automatically during inhalation. Magnets keep the valves in the breathing position. The magnetic force can be varied. Several prototypes have been tested in vitro and in situ. Results. The prototypes showed good in vitro behaviour. The range of adjustability of speech and cough was wide enough, flow resistance acceptable. This was confirmed by preliminary in vivo experiments. Patients were enthusiastic; hands-free speaking and coughing is possible. Conclusion. Numerous problems have to be solved to produce an artificial larynx. Each solution generated up till now, however, can already be applied to improve the existing rehabilitation process of laryngectomized patients.  相似文献   
8.
109 subjects aged 70 years (58 women, 51 men; average age 77 years) were hospitalized in the CICU (Cardiology Intensive Care Unit) over the period stretching from 1984 to 1986. The average length of stay in the CICU was 1 week, completed by an average stay of 5 days in the cardiology department. 100 per cent of the patients were followed up. Of the clinical parameters made evident by this study, the authors note that hypertension was the predominant risk factor (52.2 per cent); a history of coronary disease was noted in 60.5 per cent; 26.6 per cent of the patients were hospitalized before the 6th hour, chest pain being typical in 78 per cent versus painless in 11 per cent of patients; topographically, the infarction was anterior in 55 per cent, posterior in 40.4 per cent, and around the circumference in 4.6 per cent of cases; 80.8 per cent of the infarctions were transmural versus 19.2 per cent of infarctions without the Q wave--the latter accounted for a higher hospital mortality rate (38 per cent versus 27.3 per cent). The main complications were disturbances in rhythm (60.6 per cent) and LVI (56.9 per cent). Complications on the form of infections were noted in 15.6 per cent. Apart from the usual indicators of severity (cardiogenic shock, VF, LVI), infarction of the RV and AF had a serious effect on the prognosis. latrogenic disease accounted for 18.9 per cent. From the point of view of prognosis, hospital mortality was 30 per cent; mortality after one year was 44 per cent and 47.7 per cent after 2 years (in a group of 76 subjects).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
9.
Contemporary bioethics pays considerable attention to the ethical aspects of dementia care. However, ethical issues of sexuality especially as experienced by institutionalized persons with dementia are often overlooked. The relevant existing ethics literature generally applies an implicit philosophical anthropology that favors the principle of respect for autonomy and the concomitant notion of informed consent. In this article we will illustrate how this way of handling the issue fails in its duty to people with dementia. Our thesis is that a more inclusive philosophical anthropology is needed that also heeds the fate of this growing population. Drawing on the tradition of phenomenology, we will chalk out an anthropological framework that rests on four fundamental characteristics of human existence: the decentered self, human embodiment, being-in-the-world and being-with-others. Our aim in this article is thus to tentatively put forward a broader perspective for looking at aged sexuality in institutionalized people with dementia. Hopefully the developed framework will mark the beginning of a new and refreshed ethical reflection on the topic at hand.  相似文献   
10.
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