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111.
BACKGROUND: Inhaled perfluorohexan vapor has been shown to improve gas exchange and pulmonary mechanics in oleic acid- and ventilator-induced lung injury. However, in the clinical setting, lung injury frequently occurs in the context of systemic inflammation and consecutive lung injury, which may be induced experimentally by intravenous administration of endotoxin. The authors studied whether vaporized perfluorohexan is efficacious during endotoxin-induced lung injury in domestic pigs. METHODS: Twenty-two pigs (29 [23, 31] kg body weight [first, third interquartile]; tracheostomy) were anesthetized and mechanically ventilated. In the endotoxin (n = 8) and perfluorohexan groups (n = 7), we administered endotoxin of Escherichia coli 111:B4, 1 mg.kg . h for 1 h and 10 microg.kg.h for 5 h in consecutive order. In the perfluorohexan group, inhalation of the test drug was started 2 h 30 min after the start of the intravenous endotoxin and terminated after 30 min. In a control group (n=7), animals were instrumented and observed over time without further intervention. Oxygenation function was assessed from oxygen partial pressures (Po2, blood gases) and calculated shunt fraction. Respiratory compliance was calculated from airway pressure and tidal volume. Measurements were performed before and every hour during endotoxin infusion. RESULTS: After 6 h of endotoxin, gas exchange and pulmonary compliance were deteriorated in the endotoxin group (Pao2: 184 [114, 289] vs. 638 [615, 658] mmHg, pulmonary shunt fraction: 30 [23, 38] vs. 4 [3, 6]%, respiratory compliance: 12 [11, 14] vs. 22 [19, 23] ml/mbar; P < 0.05, endotoxin vs. control). Inhalation of vaporized perfluorohexan did not improve Pao 2 (107 [60, 221] mmHg), pulmonary shunt fraction (32 [26, 58]%), or respiratory compliance (14 [10, 17] ml/mbar) when compared with intravenous endotoxin (not significant, perfluorohexan vs. endotoxin). CONCLUSIONS: Inhalation of vaporized perfluorohexan does not improve pulmonary gas exchange or respiratory compliance in endotoxin-induced porcine lung injury.  相似文献   
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The ultrasonographic image of the fetal head at the appropriate level for determination of the biparietal diameter reveals an apparent asymmetry of the cerebral hemispheres. This was confirmed and analyzed in 49 sequential fetuses who had no neurologic deficits at birth and in the autopsy specimen of an 8-month-old infant without any anatomic abnormalities of the head. In the hemisphere farthest from the transducer, a crescent-shaped echo-poor region was visualized abutting the calvarium. This resembles an abnormal fluid collection but represents normal anatomy. High-amplitude reflections were observed on the medial side of the crescent and were produced by the combination of the sylvian fissure and the choroid plexus of the lateral ventricle. The fine echo pattern of the near hemisphere, which appeared to represent normal anatomy, was artifactual. The cerebral asymmetry seen by conventional ultrasonographic imaging after the 15th gestational week should not suggest an underlying pathologic process. The studies suggest that a higher-quality examination of the near hemisphere of the fetal cranium can be performed with properly focused transducers.  相似文献   
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Summary Investigations of thyroid hormone actions upon electrolyte exchange in body and tissues and upon electrophysiological properties of the heart, described in literature, are reviewed. Possible interactions of thyroid hormone effects upon efficiency of oxydative phosphorylation, upon electrolyte exchange and upon the excitability of the heart are discussed.  相似文献   
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Forty-eight children aged 5 years or less admitted consecutively with a clinical diagnosis of kwashiorkor were randomly allocated to two groups. One group was treated with milk while the other group was fed soya-maize porridge; both groups received the same supportive treatment. The recovery rate in both groups was comparable. Protein intake and the rate of rise in serum albumin and transferrin concentrations were greater in the milk-fed group. The incidence of diarrhoea was significantly less in the children fed soya-maize. Soya-maize porridge is recommended as an effective and inexpensive treatment for kwashiorkor.  相似文献   
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After brief discussion of epidemiology, aetiology, localization, diagnosis and surgical management of vascular stenoses leading to cerebral insufficiency, the results of 433 carotid artery TEAs are reported. Short- and long-term results were investigated to determine to what extent age of the patients affects outcome. The analysis of our patients sample showed with respect to perioperative mortality, morbidity and long-term outcome no significant difference between the under- and over-70-year age groups. In stage I (asymptomatic bruits) the perioperative mortality of the younger group (N = 119) was 1% and in the older group no perioperative death occurred. The long-term survival rate and the proportion of patients without neurological dysfunction after 4 years was 65% and 85% respectively for the younger group and 88% and 80% for the over 70-year age group. In stage II patients (with transient ischaemic attacks) the perioperative mortality was the same for both groups (2%). The long-term survival rate for the younger group (N = 106) was 77% and 76% in the older group (N = 91) proportion of patients without neurological dysfunction was 87% for the younger group and 93% for the older patient sample. There were no patients with stage III occlusion (acute stroke) in our patient sample. In stage IV (completed stroke) the younger patients had a perioperative mortality of 5.7%. In the older group (N = 18) no patient died perioperatively. The 2-year survival rates were 61% for the older age group and 57% für the younger. The corresponding proportions of patients without neurological dysfunction after 4 years were 83% and 71% for the older and younger patient groups respectively.  相似文献   
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Immunoreactive prolactin-like material (Ir Prl) was detected in urines of eugonadal women during the luteal phase and in urines of pregnant and lactating women. The levels of Ir Prl urinary excretion per 24 h and of elimination per 100 ml of glomerular filtrate were highest in lactating women as compared to pregnant women; levels in pregnant women were elevated as compared to eugonadal subjects. Iv injection of thyrotropin releasing hormone (TRH, 200 micrograms) caused increased levels of urinary Ir Prl. The physiochemical characteristics of urinary Ir Prl of lactating women were investigated by filtrating urine samples on Ultragel Aca 54 in presence or absence of Trasylol. Urines, supplemented with Trasylol and analyzed either immediately or after storage at room temperature for 24 h, contained in addition to the 23,000 Mr monomeric form (25.2 +/- 7.4%), two fractions of high (greater than or equal to 70,000) or low (less than 23,000) molecular weight, respectively. The latter material largely predominated (73.5 +/- 7.3%). Urines kept at room temperature for 24 h without Trasylol showed variable but significant decreases in the monomer form with a parallel increase in high MW and fragmented forms. The extent of degradation of the monomer was directly proportional to the proteolytic activity of the urines as estimated by the Azocoll breakdown test. Contrary to what was observed with the urinary endogenous monomeric Prl, human pituitary Prl remained unaltered upon incubation in Trasylol-free urines up to 45 h.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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