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141.
Hernández-Palazón J Moya Solera J Tortosa Serrano JA Ros Sempere M Burguillos López S Doménech Asensi P 《Revista espa?ola de anestesiología y reanimación》2002,49(7):346-349
OBJECTIVES: To investigate whether patients admitted to the postanesthesia recovery unit (PRU) need routine oxygen supplementation in the immediate postoperative period, by measuring changes in arterial oxygen saturation (SpO2) with a pulse oximeter. MATERIAL AND METHODS: Two hundred ninety-nine patients were admitted to the PRU after surgery. All breathed room air after their operations. During transfer to and time in the PRU, SpO2 was recorded. We administered oxygen through a face mask to patients whose SpO2 fell below 94% and to patients whose SpO2 levels fell below baseline, when baseline values were less than 94%. We recorded patient data, physical status (ASA), type of anesthesia, duration of surgery, Aldrete score upon admission to the PRU and SpO2 before and after surgery while the patient breathed room air. RESULTS: General anesthesia was used in 82.3% of the patients and local-regional anesthesia with sedation in 17.7%. PRU stay was 75.6 +/- 92.4 min. Twenty-five percent of the patients were treated with oxygen after surgery and 75% did not require supplemental oxygen. Time until the appearance of desaturation was 3.3 +/- 2.8 min. The coefficient of multiple correlation between postoperative SpO2 while breathing room air (dependent variable) and preoperative SpO2, age and duration of surgery was R = 0.522 (p < 0.001). CONCLUSIONS: Our results are sufficient to demonstrate the validity of pulse oximetry for avoiding indiscriminate oxygen supplementation in patients admitted to the PRU. 相似文献
142.
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145.
背景:在亚洲、非洲和欧洲,致病性H5N1流感病毒引起禽流感在家禽和候鸟中爆发流行,还导致了人类发病和死亡。虽然目前H5N1毒株引起人与人之间的传染不太可能,但它仍可能是未来流感大范围流行的潜在威胁因素。本试验的目的就是评价针对H5N1病毒株的裂解病毒疫苗的安全性和免疫原性。方法:对300名志愿者(年龄为18岁~40岁)进行随机、开放标签的、无对照的Ⅰ期试验。300名志愿者被分为6组:7.5mg血凝素加佐剂组(n=50)、7.5mg血凝素不加佐剂组(n=49)、15mg血凝素加佐剂组(n=50)、15mg血凝素不加佐剂组(n=50)、30mg血凝素加佐剂组(n=51)、30mg血… 相似文献
146.
Jaap Huisman Eline J Aukema Jan Berend Deijen Silvia CCM van Coeverden Gertjan JL Kaspers Heleen JH van der Pal Henriette A Delemarre-van de Waal 《BMC pediatrics》2008,8(1):25
Background
To reduce the risk of brain damage children with acute lymphoblastic leukaemia (ALL) are nowadays mainly treated with intrathecal chemotherapy (ITC) instead of central nervous system (CNS) radiation therapy (CRT) to prevent CNS relapse. However, chemotherapy may also lead to cognitive deficits. As growth hormone deficiency (GHD) or impaired growth hormone secretion are frequently found in ALL patients treated with cranial radiation therapy and/or chemotherapy, we hypothesized that GH therapy may reduce cognitive deficits in these patients. 相似文献147.
Benzo[a]pyrene at an environmentally relevant dose is slowly absorbed by, and extensively metabolized in, tracheal epithelium 总被引:2,自引:0,他引:2
Gerde P; Muggenburg BA; Thornton-Manning JR; Lewis JL; Pyon KH; Dahl AR 《Carcinogenesis》1997,18(9):1825-1832
While tobacco smoke has been conclusively identified as a lung carcinogen,
there is much debate over which smoke constituent(s) are primarily
responsible for its carcinogenicity. Previous studies in our laboratory
suggested that highly lipophilic carcinogens are slowly absorbed in the
thicker epithelium of the conducting airways, potentially allowing for
substantial local metabolism. The bioactivation of polycyclic aromatic
hydrocarbons in airway epithelium may, hence, be important in tobacco
smoke-induced carcinogenesis. In the present study, the hypothesis of slow
absorption and substantial local metabolic activation of highly lipophilic
carcinogen in airway epithelium was tested in dogs. A single dose of
tritiated benzo[a]pyrene (BaP) dissolved in a saline/phospholipid
suspension was instilled in the trachea, just anterior to the carina. At
intervals of a few minutes up to 30 min over a 3-h period, blood samples
were drawn from the azygous vein, which drains the area around the point of
instillation, and from the systemic circulation. Tissue samples were taken
at the end of the experiment. The concentration of BaP with depth into the
tracheal mucosa was determined with autoradiography. BaP was slowly
absorbed into the trachea with a half-time of approximately 73 min, which
is consistent with diffusion-limited passage through the epithelium and
lead to local doses in the tracheal epithelium that were more than a
1000-fold those of other tissues. The long retention of BaP in the
epithelium provided the local metabolizing enzymes with high substrate
levels over a long period, resulting in extensive metabolism. At 3 h after
the exposure, 23% of the BaP-equivalent activity remained in the tracheal
mucosa. Of this fraction, 13% was parent compound, 28% was organic
extractable, 31% was water-soluble, and 28-7% of the instilled dose was
bound to tracheal tissues. These results explain the tendency of highly
lipophilic carcinogens, such as BaP, to induce tumors at the site of entry
and, furthermore, indicate that the highly lipophilic components of tobacco
smoke and polluted air may be the most important contributors to lung
tumors of the conducting airways.
相似文献
148.
JL Emery 《Acta paediatrica (Oslo, Norway : 1992)》1994,83(S394):40-46
It is an honour to have been asked to contribute to this volume that commemorates the life and work of Spyros Doxiadis. Spyros was, and is still, a vital and stimulating influence on those of us who were fortunate enough to have been his colleague in all phases of his life. My period of closeness to him was when he was working in Sheffield with Ronald Illingworth. At that time (now over 40 years ago) he and Katherine were having their children and my wife and I was having ours. Then words like "bonding" had not become commonplace as today, but the functional patterns of family relationships were something about which we were intensely aware. I particularly remember a summer when we were holidaying on a tidal estuary between Anglesey and Holy Island and recall a moment when Spyros and I were sitting on a grass topped sandbank watching our children and wives at the water's edge "messing around" with a boat. We watched and discussed the beauty of the postures and poses of our womenfolk with the children and the children with each other. It was the memory of that conversation that stimulated me to propose the topic of this essay in Spyros' memory. 相似文献
149.
Effects of growth hormone therapy in prepubertal children with short stature secondary to intrauterine growth retardation 总被引:1,自引:0,他引:1
A total of 130 short children were included in a French multicentre study and randomized between a control group (group A) and two groups treated with daily subcutaneous injections of GH at doses of 0.7 IU/kg/week (group B) and 1.4 IU/kg/week (group C) for 2 years. Height velocity was significantly increased ( p <0.0005) in groups B and C, with a greater increase in group C than in group B ( p < 0.001). The benefit after 2 years compared with controls was 4.3 cm in group B and 5.9 cm in group C. The rate of bone maturation was not affected by GH therapy. These results led to the conclusion that 2 years of treatment with GH improves final height prognosis in children with short stature secondary to IUGR, and that this effect is dose dependent. The effect on final height has still to be demonstrated. 相似文献
150.
Wilson D Burniston M Moya E Parkin A Smye S Robinson P Littlewood J 《Archives of disease in childhood》1999,80(4):348-352
AIM—To investigate
deposition patterns and to assess the delivery rate of two nebuliser
systems in children with cystic fibrosis (CF).
METHODS—Thirty three children with CF on regular treatment with nebulised antibiotics had radioisotope scans performed using technetium-99m labelled aerosol antibiotic generated by a Ventstream nebuliser (median mass diameter (MMD), 3.3 µm; delivery rate, 0.075 ml/min) under conditions similar to their routine home practice. The inhomogeneity of the images was scored on a 1-10 rating scale (a low score indicating even distribution of the antibiotic), and stomach deposition was measured as a percentage of overall deposition. Twenty patients had a repeat scan using an Optimist nebuliser (MMD, 1.8 µm; delivery rate, 0.02 ml/min).
RESULTS—The mean inhomogeneity scores were 5.4 in the Ventstream group and 3.5 in the Optimist group. Mean stomach deposition was 17.3% in the 33 patients using the Ventstream nebuliser. There was an inverse relation between height and stomach deposition (r = 0.69). In the 20 patients who had both nebulisers, the mean percentages of stomach deposition for the Ventstream and Optimist nebulisers were 11.8% and 1.6%, respectively. The Ventstream nebuliser delivered antibiotic at an average 2.8 times faster rate than the Optimist nebuliser.
IMPLICATIONS—A smaller particle size results in a more homogenous distribution of the antibiotic in the lungs with decreased stomach deposition. This should not be seen as a recommendation to use the Optimist nebuliser because more antibiotic was delivered to most parts of the lung with the Ventstream because of its increased delivery rate.
相似文献
METHODS—Thirty three children with CF on regular treatment with nebulised antibiotics had radioisotope scans performed using technetium-99m labelled aerosol antibiotic generated by a Ventstream nebuliser (median mass diameter (MMD), 3.3 µm; delivery rate, 0.075 ml/min) under conditions similar to their routine home practice. The inhomogeneity of the images was scored on a 1-10 rating scale (a low score indicating even distribution of the antibiotic), and stomach deposition was measured as a percentage of overall deposition. Twenty patients had a repeat scan using an Optimist nebuliser (MMD, 1.8 µm; delivery rate, 0.02 ml/min).
RESULTS—The mean inhomogeneity scores were 5.4 in the Ventstream group and 3.5 in the Optimist group. Mean stomach deposition was 17.3% in the 33 patients using the Ventstream nebuliser. There was an inverse relation between height and stomach deposition (r = 0.69). In the 20 patients who had both nebulisers, the mean percentages of stomach deposition for the Ventstream and Optimist nebulisers were 11.8% and 1.6%, respectively. The Ventstream nebuliser delivered antibiotic at an average 2.8 times faster rate than the Optimist nebuliser.
IMPLICATIONS—A smaller particle size results in a more homogenous distribution of the antibiotic in the lungs with decreased stomach deposition. This should not be seen as a recommendation to use the Optimist nebuliser because more antibiotic was delivered to most parts of the lung with the Ventstream because of its increased delivery rate.
相似文献