No abstract

The relationship between asthma and gastro-oesophageal reflux (GER) is controversial. In an allergy department, GER prevalence was evaluated in asthmatics, with a view to judging the potential influence of GER on asthma.One hundred and five asthmatics were recruited and co-investigated for GER and lung function. Descriptive analysis was performed, patients with (GER+) and without (GER-) GER were then compared, and finally, stepwise regression analysis was used. GER prevalence was 32%.Lung parameters did not differ between GER+ and GER-patients. When restricting analysis to GER+ patients, bronchial reactivity was closely correlated to the number of reflux episodes (NRE) (r=0.983; p=0.001). When comparing patients with more than 15 reflux episodes·day -1 (n=50), with those having less (n=43), no differences were found in lung function and GER parameters. However, there was a positive correlation between the provocative dose of methacholine causing forced expiration volume to fall 20% from the baseline and NRE in patients with NRE>15 (r=0.561; p=0.05).In conclusion, gastro-oesophageal reflux was observed in a third of the asthma patients studied. These data do not support a firm aetiological relationship between gastro-oesophageal reflux and asthma, but do suggest an association between the number of reflux episodes and bronchial hyperresponsiveness. Eur Respir J 1997; 10: 2255-2259 Asthma is a bronchial disease characterized by an inflammatory process [1]. Gastro-oesophageal reflux (GER) has been suspected as a causal factor, but the relationship between GER and asthma remains controversial.The physiopathological mechanisms involved in this potential relationship are still hypothetical [2-4], although two main mechanisms are usually accepted, reflex [5][6][7] or acid inhalation [8][9][10]. A possible relationship between the severity of GER and that of asthma has not been investigated previously.GER prevalence is not precisely known in asthmatics; it has been estimated at levels of 20 to even 80% [11]. Finally, it is not known which groups of asthma patients in particular should be investigated for GER.This controversy induced us to conduct a prospective assessment of GER prevalence in a population of 105 consecutively admitted asthmatic out-patients and to search for a relationship between the development of asthma and that of GER. Materials and methods PatientsOne hundred and five consecutively admitted asthmatic out-patients were investigated. Asthma was diagnosed according to international consensus guidelines [12]. Besides clinical data, airway obstruction was measured and its reversibility was defined as a 20% improvement in forced expiratory volume in one second (FEV1) after bronchodilator administration, or a 20% decrease in FEV1 after methacholine bronchoprovocation. FEV1 was measured with a pocket-sized spirometer (Spirobank®; Isotec, Saint-Quentin, France). Results were expressed in real values and as the percentage of standard values for age, gender and height [13]. Bronchoprovocation tests w...

No abstract

Phys. Rev. Lett. _15, 964 (1965). 2 J. W. Halley, Phys. Rev. _181, 338 (1969). 3 M. J. Stephen, Phys. Rev. JJ37, 279 (1969). The analogous scattering in solid helium has been considered byThe total current density for a superconducting tunnel junction was calculated by Josephson 1 to be j =j e sine? + cr 0 (F, T)V+ a x (V 9 T)Vcos

A simple analytic theory for the operation of rf SQUID’s in the regime where the current I in the superconducting ring is a continuous function of the applied flux (nonhysteretic mode) has been extended to include the effects of screening flux LI, where L is the inductance of the ring. A comparison of calculated results with detailed measurements of the response of a rf SQUID using a toroidal Nb ring containing a Nb point contact shows excellent agreement both in cases when screening flux is significant and when it can be neglected.