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1.
Rev Sci Instrum ; 91(5): 054501, 2020 May 01.
Article in English | MEDLINE | ID: mdl-32486761

ABSTRACT

The design, implementation, and performance of a customized carbon atom beam source for the purpose of investigating solid-state reaction routes in interstellar ices in molecular clouds are discussed. The source is integrated into an existing ultrahigh vacuum setup, SURFace REaction SImulation DEvice (SURFRESIDE2), which extends this double atom (H/D, O, and N) beamline apparatus with a third atom (C) beamline to a unique system that is fully suited to explore complex organic molecule solid-state formation under representative interstellar cloud conditions. The parameter space for this system is discussed, which includes the flux of the carbon atoms hitting the ice sample, their temperature, and the potential impact of temperature on ice reactions. Much effort has been put into constraining the beam size to within the limits of the sample size with the aim of reducing carbon pollution inside the setup. How the C-atom beam performs is quantitatively studied through the example experiment, C + 18O2, and supported by computationally derived activation barriers. The potential for this source to study the solid-state formation of interstellar complex organic molecules through C-atom reactions is discussed.

2.
Phys Chem Chem Phys ; 16(18): 8257-69, 2014 May 14.
Article in English | MEDLINE | ID: mdl-24671412

ABSTRACT

The role of nitrogen and oxygen chemistry in the interstellar medium is still rather poorly understood. Nitric oxide, NO, has been proposed as an important precursor in the formation of larger N- and O-bearing species, such as hydroxylamine, NH2OH, and nitrogen oxides, NO2 and N2O. The topic of this study is the solid state consumption of NO via oxygenation and the formation of NO2 and other nitrogen oxides (ONNO2 and N2O4) under conditions close to those encountered on icy grains in quiescent interstellar clouds. In our experiments nitric oxide and oxygen allotropes (O, O2, and O3) or N atoms are co-deposited under ultra-high vacuum conditions on different substrates (silicate, graphite, compact ASW ice, and gold) at temperatures ranging between 10 and 35 K. Reaction products are monitored via Fourier Transform Reflection Absorption Infrared Spectroscopy (FT-RAIRS) and Temperature Programmed Desorption (TPD) using mass spectrometry. We find that NO2 is efficiently formed in NO + O/O2/O3/N solid surface reactions. These are essentially barrier free and offer a pathway for the formation of NO2 in space. Nitrogen dioxide, however, has not been astronomically detected, contradicting the efficient reaction channel found here. This is likely due to other pathways, including regular hydrogenation reactions, as discussed separately in part II of this study.

3.
Phys Chem Chem Phys ; 16(18): 8270-82, 2014 May 14.
Article in English | MEDLINE | ID: mdl-24671439

ABSTRACT

Nitrogen oxides are considered to be important astrochemical precursors of complex species and prebiotics. However, apart from the hydrogenation of solid NO that leads to the surface formation of hydroxylamine, little is known about the full solid state reaction network involving both nitrogen and oxygen. Our study is divided into two papers, hereby called Part I and Part II. In the accompanying paper, we investigate the surface reactions NO + O/O2/O3 and NO + N with a focus on the formation of NO2 ice. Here, we complement this study by measurements of the surface destruction of solid NO2, e.g., NO2 + H/O/N. Experiments are performed in two separate ultra-high vacuum setups and therefore under different experimental conditions to better constrain the experimental results. Surface reaction products are monitored by means of Fourier Transform Reflection Absorption Infrared Spectroscopy (FT-RAIRS) and Temperature Programmed Desorption (TPD) techniques using mass spectrometry. The surface destruction of solid NO2 leads to the formation of a series of nitrogen oxides such as NO, N2O, N2O3, and N2O4 as well as HNO, NH2OH, and H2O. When NO2 is mixed with an interstellar more relevant apolar (i.e., CO) ice, solid CO2 and HCOOH are also formed due to interactions between different reaction routes. The astrophysical implications of the full nitrogen and oxygen reaction network derived from Parts I and II are discussed.

4.
Rev Sci Instrum ; 84(7): 073112, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23902049

ABSTRACT

A new ultrahigh vacuum experiment is described to study atom and radical addition reactions in interstellar ice analogues for astronomically relevant temperatures. The new setup - SURFace REaction SImulation DEvice (SURFRESIDE(2)) - allows a systematic investigation of solid state pathways resulting in the formation of molecules of astrophysical interest. The implementation of a double beam line makes it possible to expose deposited ice molecules to different atoms and/or radicals sequentially or at the same time. Special efforts are made to perform experiments under fully controlled laboratory conditions, including precise atom flux determinations, in order to characterize reaction channels quantitatively. In this way, we can compare and combine different surface reaction channels with the aim to unravel the solid state processes at play in space. Results are constrained in situ by means of a Fourier transform infrared spectrometer and a quadrupole mass spectrometer using reflection absorption infrared spectroscopy and temperature programmed desorption, respectively. The performance of the new setup is demonstrated on the example of carbon dioxide formation by comparing the efficiency through two different solid state channels (CO + OH → CO2 + H and CO + O → CO2) for which different addition products are needed. The potential of SURFRESIDE(2) to study complex molecule formation, including nitrogen containing (prebiotic) compounds, is discussed.

5.
Klin Med (Mosk) ; 91(3): 36-40, 2013.
Article in Russian | MEDLINE | ID: mdl-23789450

ABSTRACT

We studied the role of oxalate release through the airways as a potential injurious factor in the development of inflammation, bronchial obstruction and cough syndrome (respiratory oxalosis). Detection of oxalates in bronhcoalveolar lavage fluid and daily urine is the most valuable method for diagnostics of oxalates. Systemic effects, such as cholelithiasis, urolithiasis, and spinal osteochondrosis are characteristic clinical signs of respiratory oxalosis, besides purely respiratory symptoms.


Subject(s)
Asthma/physiopathology , Asthma/urine , Hyperoxaluria/urine , Oxalic Acid/urine , Pulmonary Disease, Chronic Obstructive/physiopathology , Pulmonary Disease, Chronic Obstructive/urine , Adult , Asthma/epidemiology , Bronchi/metabolism , Comorbidity , Female , Humans , Hyperoxaluria/epidemiology , Male , Middle Aged , Pulmonary Disease, Chronic Obstructive/epidemiology
6.
Klin Med (Mosk) ; 91(8): 49-53, 2013.
Article in Russian | MEDLINE | ID: mdl-24437186

ABSTRACT

This work was aimed at estimating the role of special therapy of patients with bronchial asthma, COPD and hyperoxaluria designed to restrict the delivery or eliminate excess of oxalates and producing well apparent beneficial effect confirmed by the disappearance or decrease of clinical and functional manifestations of obstruction, reduction of requirements for broncholytic and anti-inflammatory agents.


Subject(s)
Anti-Inflammatory Agents/therapeutic use , Asthma , Bronchodilator Agents/therapeutic use , Hyperoxaluria , Oxalic Acid/metabolism , Pulmonary Disease, Chronic Obstructive , Asthma/complications , Asthma/drug therapy , Asthma/metabolism , Humans , Hyperoxaluria/complications , Hyperoxaluria/drug therapy , Hyperoxaluria/metabolism , Pulmonary Disease, Chronic Obstructive/metabolism , Pulmonary Disease, Chronic Obstructive/therapy , Treatment Outcome
7.
J Chem Phys ; 137(5): 054714, 2012 Aug 07.
Article in English | MEDLINE | ID: mdl-22894378

ABSTRACT

Hydroxylamine (NH(2)OH) is one of the potential precursors of complex pre-biotic species in space. Here, we present a detailed experimental study of hydroxylamine formation through nitric oxide (NO) surface hydrogenation for astronomically relevant conditions. The aim of this work is to investigate hydroxylamine formation efficiencies in polar (water-rich) and non-polar (carbon monoxide-rich) interstellar ice analogues. A complex reaction network involving both final (N(2)O, NH(2)OH) and intermediate (HNO, NH(2)O·, etc.) products is discussed. The main conclusion is that hydroxyl-amine formation takes place via a fast and barrierless mechanism and it is found to be even more abundantly formed in a water-rich environment at lower temperatures. In parallel, we experimentally verify the non-formation of hydroxylamine upon UV photolysis of NO ice at cryogenic temperatures as well as the non-detection of NC- and NCO-bond bearing species after UV processing of NO in carbon monoxide-rich ices. Our results are implemented into an astrochemical reaction model, which shows that NH(2)OH is abundant in the solid phase under dark molecular cloud conditions. Once NH(2)OH desorbs from the ice grains, it becomes available to form more complex species (e.g., glycine and ß-alanine) in gas phase reaction schemes.

10.
Ter Arkh ; 79(3): 37-41, 2007.
Article in Russian | MEDLINE | ID: mdl-17526194

ABSTRACT

AIM: To evaluate peculiarities of a clinical course and changes in bronchial mucosa in bronchial asthma (BA) patients with chronic obstructive pulmonary disease (COPD) in combination with hyperoxaluria (HOU); informative value of some laboratory and device findings including oxalates assay in bronchial lavage fluid for specification of the diagnosis, role of oxalates in development of obstructive syndrome and choice of optimal therapy. MATERIAL AND METHODS: Oxalates were examined in daily urine, bronchoalveolar lavage fluid and exhaled air condensate of 104 patients with BA and COPD, 77 of which had HOU and an atypical course of bronchial obstruction syndrome. RESULTS: Conception of airways inflammation in patients with oxalate metabolism disturbances is proposed. It is shown that insoluble oxalates participate in pathogenesis of bronchial obstruction. CONCLUSION: Oxalate metabolism disturbances are an important factor in pathogenesis of airways inflammation and development of bronchial obstruction in predisposed patients. Therefore, administration of insoluble oxalates lowering therapy may effectively prevent formation and progression of obstructive pulmonary diseases in this group of patients.


Subject(s)
Asthma/metabolism , Bronchi/metabolism , Hyperoxaluria/metabolism , Oxalates/analysis , Pulmonary Disease, Chronic Obstructive/metabolism , Asthma/complications , Asthma/diagnosis , Breath Tests , Bronchoalveolar Lavage Fluid/chemistry , Diagnosis, Differential , Humans , Hyperoxaluria/complications , Hyperoxaluria/diagnosis , Oxalates/urine , Pulmonary Disease, Chronic Obstructive/complications , Pulmonary Disease, Chronic Obstructive/diagnosis
11.
Aviakosm Ekolog Med ; 38(4): 3-14, 2004.
Article in Russian | MEDLINE | ID: mdl-15500164

ABSTRACT

All plausible artificial radioactive sources entering the near-Earth space (NES) were systematized and consequences of various large radiation accidents and catastrophes to Earth and NES were analyzed. Aggressive "population" of near-Earth orbits by space stations with rotating crews, unmanned research platforms and observatories extends "borderlines" of the noosphere raising at the same time concerns about the noosphere radiation safety and global radioecology. Specifically, consideration is given to the facts of negative effects of space power reactor facilities on results of orbital astrophysical investigations.


Subject(s)
Cosmic Radiation/adverse effects , Extraterrestrial Environment , Hazardous Substances/adverse effects , Space Flight/instrumentation , Earth, Planet , Humans , Models, Statistical , Moon , Radiation Dosage , Radiation Monitoring/instrumentation , Radiation Protection , Radioactive Hazard Release , Radiometry , Solar Activity
12.
Ter Arkh ; 75(3): 24-7, 2003.
Article in Russian | MEDLINE | ID: mdl-12718215

ABSTRACT

AIM: To evaluate the energy informational effects of various treatments in patients with bronchial asthma (BA). MATERIAL AND METHODS: Changes in bioenergograms were analyzed in 139 patients after therapeutical exposures: intravenous prednizolone and dexamethasone, inhaled seretide, fluthicasone propionate, beclomethasone, phenoterol, salmeterol, and salbutamol, the latter drug as tablets, as well as a course treatment with acupuncture. The energy informational effects of pumpan and nitrosorbide were studied in 22 patients with BA concurrent with cor pulmonale and coronary heart disease (CHD). RESULTS: A significant difference was found in the parameters of a bioenergogram depending on the routes of administrations of the drugs and their dosage forms. The greatest and positive changes in the area of the bioenergogram were recorded when using salmeterol and salbutamol, particularly in the nebulization of their solutions, and acupuncture. The intravenous infusion of glucocorticosteroids frequently produced inhibitory effects. In patients with BA concurrent with cor pulmonale and CHD, the positive energy informational effect of pumpan, that differed from that of nitrosorbide, occurred with better ventricular repolarization and alleviated signs of right cardiac overload on ECG. CONCLUSION: The bioenergogram is highly sensitive to changes in the status of patients and it may be used to choose drugs and their combinations, combined drug therapy, and acupuncture on an individual basis. Pumpan is recommended for the treatment of patients with BA concurrent with cor pulmonale.


Subject(s)
Acupuncture , Anti-Asthmatic Agents/therapeutic use , Asthma/metabolism , Adult , Asthma/drug therapy , Asthma/therapy , Energy Metabolism , Humans , Middle Aged
13.
Ter Arkh ; 75(1): 23-6, 2003.
Article in Russian | MEDLINE | ID: mdl-12652950

ABSTRACT

AIM: To evaluate prevalence of bronchial asthma (BA) and allergic rhinitis (AR) among adult population of St-Petersburg. MATERIAL AND METHODS: Responders to ECRHS and B. Sibbald & E. Rink questionnaires who gave at least one positive answer were examined clinically, functionally and allergologically. A total of 3634 responders aged 16 to 98 years participated in the study. RESULTS: By the answers of the responders prevalence of BA was 7.2%, of AR--9.9%. Such figures were much higher than official statistics. Atopic BA was most frequent among other types--64%. CONCLUSION: It became evident that BA and AR in many cases are diagnosed late or are not recognized at all. This leads to growing number of patients with moderate and severe course of these diseases and deteriorates effectiveness of BA and AR treatment.


Subject(s)
Asthma/epidemiology , Hypersensitivity/epidemiology , Rhinitis/epidemiology , Adolescent , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Prevalence , Russia/epidemiology
14.
Klin Med (Mosk) ; 81(12): 47-51, 2003.
Article in Russian | MEDLINE | ID: mdl-14971157

ABSTRACT

To characterize membrane-receptor peculiarities of the adrenergic and histaminergic systems under the model of peroxide and hyperosmolar effect in atopic bronchial asthma (ABA) and preclinical stage of BA, we have examined 25 patients with ABA, 19 patients with nonpulmonary allergy, 28 healthy men and 21 healthy blood relatives of ABA patients. The phenomenon of inversion of the effect of beta-adrenoblocker (obzidan) and of the combined effect of histamine and H1-antagonist (dimedrol) was revealed in ABA patients. The same phenomenon was registered at the preclinical stage of BA. In ABA and in preclinical BA the shift of H1/H2-histaminergic balance to increased H1-activity exists. Peroxide and hyperosmolar effects modeled on red cell membranes allowed us to characterize reactivity of adrenergic and histaminergic systems not only in ABA but also in preclinical BA.


Subject(s)
Adrenergic beta-Antagonists/pharmacology , Anti-Asthmatic Agents/pharmacology , Asthma/drug therapy , Asthma/metabolism , Diphenhydramine/pharmacology , Histamine H1 Antagonists/pharmacology , Propranolol/pharmacology , Adrenergic beta-Antagonists/therapeutic use , Adult , Aged , Anti-Asthmatic Agents/therapeutic use , Diphenhydramine/therapeutic use , Female , Histamine H1 Antagonists/therapeutic use , Humans , Male , Middle Aged , Osmolar Concentration , Peroxides/metabolism , Propranolol/therapeutic use
15.
Eur Respir J ; 20(3): 596-600, 2002 Sep.
Article in English | MEDLINE | ID: mdl-12358334

ABSTRACT

Asthma is a chronic inflammatory disease of the airways mediated, at least in part, by leukotrienes and other lipid mediators. Experimental studies have shown that lipid extract of New Zealand green-lipped mussel, Perna canaliculus, is effective in inhibiting 5'-lipoxygenase and cyclo-oxygenase pathways responsible for production of eicosanoids, including leukotrienes and prostaglandins. The aim of this study was to assess its effect on symptoms, peak expiratory flow (PEF) and hydrogen peroxide (H2O2) in expired breath condensate as a marker of airway inflammation in patients with steroid-naïve atopic asthma in a double-blind randomised, placebo-controlled clinical trial. Forty six patients with atopic asthma received two capsules of lipid extract (Lyprinol) or placebo b.i.d for 8 weeks. Each capsule of lipid extract contained 50 mg omega-3 polyunsaturated fatty acids and 100 mg olive oil, whereas placebo capsules contained only 150 mg olive oil. There was a significant decrease in daytime wheeze, the concentration of exhaled H2O2 and an increase in morning PEF in the lipid extract group compared to the placebo group. There were no significant side-effects. The authors conclude that lipid extract of New Zealand green-lipped mussel may have some beneficial effect in patients with atopic asthma.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Asthma/drug therapy , Lipids/therapeutic use , Lipoxygenase Inhibitors/therapeutic use , Adolescent , Adult , Animals , Anti-Asthmatic Agents/therapeutic use , Asthma/physiopathology , Bivalvia , Breath Tests , Double-Blind Method , Forced Expiratory Volume , Humans , Hydrogen Peroxide/analysis , Middle Aged , Peak Expiratory Flow Rate , Tissue Extracts/therapeutic use
16.
Ter Arkh ; 74(3): 14-7, 2002.
Article in Russian | MEDLINE | ID: mdl-11980112

ABSTRACT

AIM: Analysis of insulin-reactive system of erythrocytes and carbohydrate metabolism in bronchial asthma (BA) at cell and other levels. MATERIAL AND METHODS: 106 patients with BA, 26 healthy subjects and 10 healthy subjects with familial history of atopy participated in the study. Glucose tolerance and colorimetric tests were made to measure glucose, glycosylated hemoglobin, respectively. Erythrocytic insulin reactivity was assessed using an original method. Bronchial resistance was determined and specific bronchial conduction was calculated. Acetylcholine test was conducted before and after a single inhalation of 5% isoosmolar glucose solution. RESULTS: Atopic BA was characterized by a trend to hypoglycemia, low glycosylation of red cell hemoglobin, impaired membrane transport of glucose in red cells, a hypoglycemic type of glucose tolerance test curve, a paradoxical reaction of erythrocytes to insulin and adrenaline--release of glucose. CONCLUSION: The detected changes in cell insulin reactivity in atopic BA and positive effects of 5% glucose solution inhalations on bronchial hyperreactivity in BA patients provide grounds for development of new therapeutic approaches in BA.


Subject(s)
Asthma/metabolism , Carbohydrate Metabolism , Erythrocytes/metabolism , Insulin , Adolescent , Adult , Aged , Aged, 80 and over , Asthma/blood , Blood Glucose/analysis , Epinephrine , Erythrocyte Membrane/metabolism , Female , Glucose Tolerance Test , Glycated Hemoglobin/analysis , Humans , Male , Middle Aged , Monosaccharide Transport Proteins/metabolism
17.
Chest ; 120(4): 1136-9, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11591550

ABSTRACT

BACKGROUND: Airway inflammation is important in the development and progression of asthma. Activation of inflammatory cells induces a respiratory burst resulting in the production of reactive oxygen species, such as H(2)O(2). The aim of this study was to measure the concentration of H(2)O(2) in exhaled breath condensate and its correlation with airway obstruction, airway hyperresponsiveness, and concentration of eosinophil cationic protein (ECP) in serum in 70 steroid-naive, atopic patients with unstable asthma (20 men; age range, 18 to 62 years) and 17 normal subjects (7 men; age range, 19 to 34 years). METHODS: Exhaled H(2)O(2) was measured using a colorimetric assay, and the concentration of ECP in serum was measured using radioimmunoassay. Airway hyperresponsiveness was expressed as the provocative concentration of inhaled histamine causing a 20% fall in FEV(1) (PC(20)). RESULTS: In patients with asthma, the mean H(2)O(2) concentration was significantly elevated compared to values in normal subjects: 0.127 +/- 0.083 mol/L vs 0.024 +/- 0.016 mol/L (p < 0.001). There was a significant correlation among H(2)O(2) concentration, FEV(1), PC(20), and ECP in serum. CONCLUSION: We conclude that exhaled H(2)O(2) is significantly elevated in asthmatic patients. This is correlated with disease severity and indirect markers of airway inflammation. Measurement of exhaled H(2)O(2) may be useful to assess airway inflammation and oxidative stress in asthmatic patients.


Subject(s)
Asthma/diagnosis , Breath Tests , Hydrogen Peroxide/analysis , Ribonucleases , Adolescent , Adult , Airway Obstruction/diagnosis , Airway Obstruction/physiopathology , Asthma/physiopathology , Blood Proteins/physiology , Bronchial Hyperreactivity/diagnosis , Bronchial Hyperreactivity/physiopathology , Bronchial Provocation Tests , Eosinophil Granule Proteins , Female , Forced Expiratory Volume/physiology , Humans , Male , Middle Aged , Risk Factors
18.
Vestn Ross Akad Med Nauk ; (12): 42-4, 2000.
Article in Russian | MEDLINE | ID: mdl-11202643

ABSTRACT

The paper considers bronchial asthma as a polygenic disease. It presents some data available in the literature on the role of genetic disorders in the development of atopic states and the authors' own findings of various biological defects detected in apparently healthy blood relatives of patients with bronchial asthma. It is concluded that premorbid diagnosis is of importance in high risk persons.


Subject(s)
Asthma/diagnosis , Asthma/genetics , Disease Progression , Environmental Exposure/adverse effects , Genetic Predisposition to Disease , Humans , Hypersensitivity, Immediate/diagnosis , Hypersensitivity, Immediate/genetics , Prognosis
19.
Eur Respir J ; 13(1): 38-40, 1999 Jan.
Article in English | MEDLINE | ID: mdl-10836320

ABSTRACT

Magnesium is important in the regulation of bronchomotor tone, and low dietary intake of magnesium has been associated with airway hyperresponsiveness in epidemiological studies. The concentration of magnesium in serum, erythrocytes and urine in 49 patients with asthma (29 males, aged 15-65 yrs) and in 25 normal subjects (15 males, aged 17-36 yrs) was studied by atomic absorption. Magnesium concentrations were significantly lower in erythrocytes and urine in both atopic (n = 26) and nonatopic (n = 23) asthmatic patients as compared with the control group, whereas serum concentrations did not differ. The concentration of magnesium in erythrocytes was not related to the degree of airway obstruction as measured by forced expiratory volume in one second (FEV1) but was significantly correlated with airway hyperresponsiveness measured as the provocative concentration causing a 20% fall in FEV1 to inhaled acetylcholine (r = 0.64; p<0.05). In addition, a magnesium tolerance test showed increased retention of magnesium (58.9% of administered dose in asthmatic patients compared with 8.9% in normal subjects, p<0.05). In conclusion, the low cellular concentration of magnesium may be associated with airway hyperresponsiveness in asthmatic patients.


Subject(s)
Asthma/metabolism , Erythrocytes/chemistry , Magnesium/analysis , Magnesium/metabolism , Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged
20.
Antibiot Khimioter ; 43(10): 24-6, 1998.
Article in Russian | MEDLINE | ID: mdl-9825106

ABSTRACT

Comparative efficacy of lomefloxacin (400 mg daily for 5 days) and roxithromycin (150 mg daily for 5 days) was studied in the treatment of 24 patients (12 males and 12 females) at the age of 39 to 83 years (the average age of 59 years) with exacerbation of chronic obstructive bronchitis. The efficacy was estimated by the clinical data and the results of the bacteriological analysis of the sputum. The drugs were shown to be equivalent in their clinical and microbiological efficacies. The use of the drugs should be based on the results of the sputum bacteriological analysis and the pathogen susceptibility tests. The tolerance of roxithromycin and lomefloxacin was good. No significant adverse events were recorded.


Subject(s)
Anti-Infective Agents/therapeutic use , Bronchitis/drug therapy , Fluoroquinolones , Quinolones/therapeutic use , Adult , Aged , Aged, 80 and over , Anti-Bacterial Agents/administration & dosage , Anti-Bacterial Agents/therapeutic use , Anti-Infective Agents/administration & dosage , Bronchitis/microbiology , Chronic Disease , Female , Humans , Male , Middle Aged , Moraxella catarrhalis/drug effects , Moraxella catarrhalis/isolation & purification , Neisseria/drug effects , Neisseria/isolation & purification , Quinolones/administration & dosage , Roxithromycin/administration & dosage , Roxithromycin/therapeutic use , Sputum/microbiology , Staphylococcus aureus/drug effects , Staphylococcus aureus/isolation & purification , Streptococcus/drug effects , Streptococcus/isolation & purification
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