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1.
Respiratory infections are the most common infection in children. They differ remarkably according to age, bacteria and viruses. Therefore a careful history of outbreak, age, former infections, involvement of surroundings, symptoms, etc are essential. The present study included 50 children, aged between 0.3 and 12 yrs, all treated ambulatorily. 21 received brodimoprim (B) and 29 erythromycin (E). Indications were: tonsillitis, bronchitis, otitis media, sinusitis and scarlet fever. Dosages were: B was given 10 mg/kg body weight (b.w.) initially followed by 5 mg/kg b.w., once-a-day. The duration of treatment varied between 4 and 14 days (mean 8.3 days). E was given 30.50 mg/kg b.w. 3 times per day; duration 4 to 14 days (mean 8.6 days). Overall results were: in group B:12 cures, 5 improvements, 3 failures; 1 not assessable. In group E: 20 cures, 8 improvements, 1 failure. Side effects: in group B: vomiting (1), skin reaction (2), discontinuation (2); in group E: skin reaction (1), diarrhea (5), diarrhea+vomiting (1); discontinuation (2). The differences in efficacy and tolerability in the two groups are not statistically significant. The improved compliance with a single versus t.i.d. dosages has to be taken into account.  相似文献   
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We have investigated the dynamic behavior of a nonionic micellar solution of tetra-ethylene glycoln-decylether (C10 E4) in water near its critical point in the presence of shear. The non-Newtonian behavior of the viscosity can be represented by * = [ 1 +a(S4)=]2, where* is the viscosity in the absence of shear,S is the shear rate. 4 is the lifetime of the critical Iluctuations,a is a system-dependent constant, and = 0.02 In addition, we have found that, before attaining a steady state, the sheared mixture undergoing phase separation shows significant shear-dependent rheological effects due to the presence of concentration domains.Paper presented at the Twelfth Symposium on Thermophysical Properties, June 19–24. 1994, Boulder, Colorado, U.S.A.  相似文献   
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Summary Detection and determination of traces of sulphites in foods was attempted by use of the modified Rankine apparatus and pararosaniline colorimetry. Replacement of alkaline titration reported previously by pararosaniline colorimetry lowered the absolute detection limit from 30 g (titration method) to 2 g. In view of clean analysis, in the color developing system, 0.1 N-sodium hydroxide was used in place of mercuric chloride solution commonly used as an absorbant of sulphites. In order to prevent oxidative decomposition of sulphites during operation, nitrogen gas was used as carrier instead of air. Dimedone and sodium azide were used for the elimination of aldehydes and nitrites, respecitvely, in the sample, which will disturb the color development of sulphites with pararosaniline-formaldehyde reagents. With this improved method, it was possible to determine the residual sulphites in frozen peeled shrimps, sugared beans and other foods with low sulphite contents accurately.
Colorimetrische Mikrobestimmung von Sulfiten in Lebensmitteln bei Anwendung der modifizierten IV. Rankine Apparatur
Zusammenfassung Geringe Sulfitmengen in Lebensmitteln (geschälte Garnelen, gezuckerte Bohnen) können colorimetrisch bestimmt werden. Die neuentwickelte Methode beruht auf einer Kombination von colorimetrischer Bestimmung mittels p-Rosanilin und der Bestimmungsmethode nach Rankine. Auf diese Weise lassen sich Gehalte von 2 g noch genau bestimmen. Bei der Farbentwicklung wurde das giftige Quecksilbertetrachlorid durch 0.1 n-NaOH ersetzt, anstelle von Luft Stickstoff als Trägergas verwendet und somit eine Oxydation des Sulfits während der Bestimmung vermieden. Da Nitrit und Aldehyde die Farbentwicklung stören, wurde ihr Einfluß durch Dimedon und Natriumazid ausgeschaltet.


Studies on the Analyses of Sulphites in Foods (IV)  相似文献   
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Uranium concentrations in drainage water are typically determined by α-spectrometry. However, due to the low specific radioactivity of uranium, the evaporation of large volumes of drainage water, followed by several hours of measurements, is required. Thus, the development of a rapid and simple detection method for uranium in drainage water would enhance the operation efficiency of radiation control workers. We herein propose a novel methodology based on total reflection X-ray fluorescence (TXRF) for the measurement of uranium in contaminated water. TXRF is a particularly desirable method for the rapid and simple evaluation of uranium in contaminated water, as chemical pretreatment of the sample solution is not necessary, measurement times are typically several seconds, and the required sample volume is low. We herein employed sample solutions containing several different concentrations of uranyl acetate with yttrium as an internal standard. The solutions were placed onto sample holders, and were dried prior to TXRF measurements. The relative intensity, otherwise defined as the net intensity ratio of the Lα peak of uranium to the Kα peak of yttrium, was directly proportional to the uranium concentration. Using this method, a TXRF detection limit for uranium in contaminated water of 0.30 µg/g was achieved.  相似文献   
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The increase in electric power consumption in industry has led to the development of modern distribution systems such as control centers having high kVA ratings and high prospective fault current. In such a situation, the improvement of the system usefulness such as reliability and cost effectiveness is the essential requirement. An index is presented to evaluate the system usefulness using the cost effectiveness for fault protection in a system of given bank kVA. The index is estimated on four different system structures of control centers, including one which utilizes Permanent Power Fuses (PPF). It is presented that the PPF combined with molded case circuit breaker in main circuit effectively improves the cost effectiveness in control centers with high fault current. Operating principles of the PPF and the control center utilizing the PPF are briefly outlined.  相似文献   
9.
The effect of microstructures on resistance to corrosion fatigue cracking and fracture surface morphology for age-hardened steels were investigated in a 3.5% NaCl aqueous solution under a cathodic potential of –0.85 V (Ag/AgCl). The free corrosion was about –0.63 V (Ag/AgCl). The resistance to corrosion fatigue cracking of materials containing coherent precipitates in the matrix (underaged conditions) was less than that of materials containing incoherent precipitates (reheated conditions) at equal strength levels. Accelerated fatigue crack growth rates of the underaged material in the aqueous solution were followed by cracking along prior-austenite grain boundaries, due to hydrogen embrittlement, while the overaged material did not show accelerated fatigue crack growth rates and had fracture surfaces similar to those in air. The difference in the fracture surfaces of both materials in air and in the aqueous solution was considered to depend on the ease of diffusion of hydrogen to the prior-austenite grain boundaries. It is concluded that incoherent precipitates in the matrix made hydrogen accumulation at prior-austenite grain boundaries much slower than for coherent precipitates.  相似文献   
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BACKGROUND: Most adult anatomical texts state that the deep inguinal ring is situated midway between the anterior superior iliac spine and the pubic tubercle. The aim of this study was to determine if this was true in prepubescent children. METHODS: A total of 107 inguinal ligaments and canals were measured during inguinal operations in 80 children (68 boys, age range 1-118 months). RESULTS: The length of the inguinal ligament increased from a median of 4.3 cm (range 3.6-6.8) at less than 1 year of age to 7.5 cm (range 6.7-10.1) at over 4 years of age. The internal ring was situated medial to the midpoint of the inguinal ligament throughout childhood. The ratio of internal ring to public tubercle over inguinal ligament length was 42% (range 27-58) at less than 2 years; and 34% (range 25-46) at over 4 years. The inguinal canal remained short (median 1 cm (range 0.7-1.1) at less than 2 years, and median 1.1 cm (range 0.7-2.3) at over 4 years) suggesting that growth of the inguinal region in this age group occurs outside the canal. CONCLUSIONS: These results have implications for the siting of incisions, and question the necessity of opening the inguinal canal in children.  相似文献   
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