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961.
The construction of hybrids between the variable fragment (Fv) of antibodies and protein MalE of Escherichia coli at the genetic level makes possible their preparation in a functional state, independently of any interaction with the antigen. We used such hybrids and a mutagenesis approach to study the recognition between antibody D1.3 and its antigen lysozyme, and its maturation. We subsequently transformed D1.3 into a reagentless fluorescent biosensor by knowledge-based design.  相似文献   
962.
963.
OBJECTIVE: To understand the national utilization pattern of heat and moisture exchangers (HME) and heated humidifiers (HH) in mechanically ventilated ICU patients. DESIGN: Cross-sectional survey. POPULATION: ICU directors in French and Canadian university-affiliated hospitals. Response rate was 89%. MEASUREMENTS: We asked respondents whether they primarily used HME or HH. We recorded whether HME were used in all patients and for how long, how often they were changed, for whom, and why they were not used. RESULTS: HME were used more often in France HH in Canada. HME were more likely to be used for all patients in France than in Canada (63% vs. 13% and for any duration of ventilation (93% vs. 35%). Short-term use of HME was more common in Canada than in France (59% vs. 7%). HME were primarily changed every day in both countries. The patients for whom HME were not used and reasons for nonutilization were similar in France and Canada. The variable of country was the strongest predictor of HME utilization for every patient (France vs. Canada, odds ratio 11) and utilization for periods of 5 days or less (Canada vs. France, odds ratio 22). CONCLUSIONS: HME were reportedly used more in often in France than in Canada for the entire duration of mechanical ventilation. This survey highlights perceptions and practices related to the determinants and consequences of airway humidification and suggests differences in the cost of mechanical ventilation between countries  相似文献   
964.
OBJECTIVE: The pressure-volume (P/V) curve has been proposed as a tool to adjust the ventilatory settings in cases of acute respiratory distress syndrome (ARDS). The aim of this study was to test the influence of P/V tracing methodology on the presence and value of the upper inflection point (UIP). METHODS: In 13 medical ARDS patients, the interruption and the automated low flow inflation methods were compared while the patients were ventilated at conventional (10-12 ml/kg) and at low (5-6 ml/kg) tidal volume (Vt). Two levels of inspiratory flow and insufflation time were used (3 and 6 s). RESULTS: No significant difference in UIP was found between the static and the dynamic methods, whatever the flow used. At Vt 10-12 ml/kg, the static and dynamic UIPs were 22.4 +/- 4.4 cmH(2)O and 22.1 +/- 4.5 cmH(2)O ( p = 0.86), respectively; at Vt of 5-6 ml/kg, the static and dynamic UIPs were 26.6 +/- 4.1 cmH(2)O and 25.5 +/- 5 cmH(2)O ( p = 0.34), respectively. Significant differences in UIP were found, in the static and dynamic conditions, between the two levels of Vt ( p < 0.005): it was lower with the higher Vt, suggesting that UIP is dependent on previous tidal alveolar recruitment. CONCLUSION: Interruption and continuous flow techniques gave similar results, but the previous Vt influences the pressure value of the UIP.  相似文献   
965.
966.
INTRODUCTION: Fabry's disease is due to alpha-galactosidase deficiency. This rare lysosomal storage disease is transmitted by recessive X-linked heredity. Sphingolipids (galactosyl-glucosyl-ceramide) accumulate in many organs. CASE REPORT: A 19-year-old man with known hypoparathyroidism presented with telangiectasia and angiokeratomas on the buttocks, the hips, the hands and around the navel. For many years, he suffered from paroxysmal pain in the hands and feet. From childhood, he had complained of diffuse abdominal pain, associated with diarrhea. Ophthalmological slit lamp fundus examination showed corneal telangiectasia and cornea verticella. There was no kidney or heart involvement. The diagnosis of Fabry's disease was confirmed by very low levels of alpha-galactosidase. DISCUSSION: We did not find any other association of hypoparathyroidism and Fabry's disease in the literature. Hypoparathyroidism is not a manifestation of Fabry's disease. Idiopathic hypoparathyroidism is very rare and a genetic origin is known. This disease can be recessive X-linked. A co-transmission of idiopathic hypoparathyroidism and Fabry's disease is probable in our patient.  相似文献   
967.
Platypnoea-orthodeoxia (P.O.) syndrome is the association of dyspnoea and arterial oxygen desaturation aggravated in the erect position and relieved in the supine position. Initially considered very rare (20 cases reported over fifty years) and occurring essentially in patients having undergone pneumonectomy, it in fact occurs much more frequently if only it is looked for (20 extra cases reported in a single year). Some new aetiologies have been described, in particular dilatations or aneurysms of the ascending aorta. Diagnosis is made easier if the oxygen saturation is measured in the supine position when it is normal, and in the erect position when it falls considerably. Another argument is added by the small effect of inspiration of high concentrations of oxygen. Contrast echocardiography confirms the right-left shunt and allows estimation of the site. This is usually situated at the atrial level, via an inter-atrial communication or more often a patent foramen ovale; as a rule the area of dehiscence having been modified by the associated pathology allowing the right-left shunt despite normal right pressures. Exceptionally the shunt is situated at the vascular or pulmonary parenchymal level. Poor tolerance of P.O. syndrome justifies a therapeutic procedure; this is usually closure of the septal fault with an occluder introduced percutaneously; the results are generally highly spectacular.  相似文献   
968.
969.
Recently, linkage analysis of a series of familial chronic lymphocytic leukaemia (CLL) showed that affected sibling pairs did not share common major histocompatibilty complex haplotypes. We analysed Class I and II antigens in 11 Italian families with familial CLL. Although there was no association of disease status with any particular human leucocyte antigen, there was an overrepresentation of DRB1 11 alleles in these families (P = 0.009). A similar trend was also observed in a second series of nine French families (P = 0.002). Larger studies are needed to determine whether non-inherited paternal or maternal DRB1 antigens play a role in familial CLL development.  相似文献   
970.
OBJECTIVE: To investigate the predictive value of transcranial magnetic stimulation (TMS) for the development of reflex sympathetic dystrophy (RSD) poststroke. DESIGN: Blind clinical assessment of 2 groups of stroke patients defined on the basis of absent or preserved motor evoked potentials (MEPs) on the affected side. SETTING: Stroke rehabilitation center. PATIENTS: Twenty stroke patients between the ages of 41 and 85 years, undergoing rehabilitation. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: MEPs from upper limbs 30 days poststroke, Motricity Index, and scoring of RSD using the Enjalbert Scale 73 days poststroke. RESULTS: A good correlation was found between Motricity Index and TMS results (P<.01). Average Enjalbert scores were significantly different between the 2 groups (P=.03). No significant correlation was found between Enjalbert scores and the Motricity Index. CONCLUSIONS: Although no significant relationship was found between upper-limb motor impairment and intensity of RSD 10 weeks after stroke, the TMS responses permitted the early categorization of patients into 2 groups that developed significantly different average Enjalbert scores 1 to 2 months later when this clinical condition was fully developed.  相似文献   
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