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71.
Effects of inhalation of corticosteroids immediately after experimental chlorine gas lung injury 总被引:7,自引:0,他引:7
BACKGROUND: To assess the effects of treatment with nebulized corticosteroids immediately after chlorine gas injury. METHODS: Eighteen anesthetized and mechanically ventilated pigs were exposed to chlorine gas (140 ppm for 10 minutes) and observed for 6 hours. Nine pigs were treated with nebulized beclomethasone-dipropionate 20 microg/kg (BDP group), and nine pigs were given no treatment (control group). RESULTS: All animals developed severe pulmonary dysfunction. The initial decrease in PaO2 was similar in both groups, but BDP-treated animals improved whereas control animals deteriorated (p < 0.005; analysis of variance). Pulmonary vascular resistance increased in both groups but less in the BDP group (p < 0.01). Lung-thorax compliance was better preserved in the BDP group (p < 0.01), and oxygen delivery was significantly better in the BDP group (p < 0.01). One animal died in the BDP group, as did three animals in the control group. CONCLUSION: Immediate treatment with nebulized BDP improved pulmonary and cardiovascular function after experimental chlorine gas injury. 相似文献
72.
The growing demand for wood-based panels for buildings and furniture and the increasing worldwide concern for reducing the pressure on forest resources require alternatives to wood raw materials. The agricultural industry not only can provide raw materials from non-wood plants but also numerous residues and side streams. This review supplies an overview of the availability, chemical composition, and fiber characteristics of non-wood lignocellulosic materials and agricultural residues, i.e., grow care residues, harvest residues, and process residues, and their relevance for use in wood panel manufacturing. During the crop harvest, there are millions of tons of residues in the form of stalks, among other things. Usually, these are only available seasonally without using storage capacity. Process residues, on the other hand, can be taken from ongoing production and processed further. Fiber characteristics and chemical composition affect the panel properties. Alternatives to wood with long fibers and high cellulose content offer sufficient mechanical strength in different panel types. In general, the addition of wood substitutes up to approximately 30% provides panels with the required strength properties. However, other parameters must be considered, such as pressing temperature, adhesive type, press levels, and pretreatments of the raw material. The search for new raw materials for wood panels should focus on availability throughout the year, the corresponding chemical requirements and market competition. Panel type and production process can be adapted to different raw materials to fit niche products. 相似文献
73.
Kadioglu A Grohmann W Depko A Levinson IP Sun F Collins S 《The journal of sexual medicine》2008,5(3):726-734
74.
Impaired placentation is a key step in the pathogenesis of important pregnancy disorders such as preeclampsia and fetal growth restriction. A role of angiotensin II in placental development can be assumed from the expression of angiotensin receptors on trophoblast from the earliest stages of pregnancy. To understand the role of angiotensin II type 1 (AT1) receptors in placental development, we investigated placentae of AT1a-deficient mice early in pregnancy (day 13 postconception). The number of alive newborns was significantly reduced in AT1a-deficient mice caused by placental malformations in 30% of all utero-placental units. Importantly, no embryonic structure was observable within the uterine segments harboring the malformed placentae. Immunohistochemistry with an antibody against murine betahCG-equivalent stained homogenously in almost all cells in the altered placentae indicating still an endocrine-active trophoblast. However, the typical structure of the murine wild-type placenta in spongiotrophoblast, giant cells, and labyrinth was abolished in malformed placental tissue deficient in the AT1a receptor. Recent epidemiological studies revealed the detrimental effect of an AT1 blockade for fetal outcome due to renal malformations and a reduced birth weight. For the latter, our findings provide an early mechanistic explanation. The lack in AT1 stimulation causes an impaired trophoblast maturation leading to impaired placental function. 相似文献
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76.
Nagel HT de Haan TR Vandenbussche FP Oepkes D Walther FJ 《Obstetrics and gynecology》2007,109(1):42-47
OBJECTIVE: To evaluate neurodevelopmental status of children treated with intrauterine red blood cell and platelet transfusion for fetal hydrops caused by parvovirus B19. METHODS: Maternal and neonatal records of all intrauterine transfusions for congenital parvovirus B19 infection in our center between 1997 and 2005 were reviewed. Congenital B19 virus infection was confirmed by the presence of parvovirus B19-specific immunoglobulin M or parvovirus B19 DNA in fetal blood samples. All children underwent a general pediatric and neurological examination. Primary outcome measure was neurodevelopmental status (developmental index by Bayley Scales of Infant Development or Snijders-Oomen test). Secondary outcome measure was general health status of surviving children. RESULTS: A total of 25 intrauterine transfusions were performed in 24 hydropic fetuses. Median fetal hemoglobin concentration, platelet count, and blood pH before intrauterine transfusions were 4.5 g/dL (range 2.4-11.4 g/dL), 79x10(9)/L (range 37-238x10(9)/L) and 7.36 (range 7.31-7.51), respectively. Sixteen survivors aged 6 months to 8 years were included in the follow-up study. Eleven children (68%) were normal, and 5 children (32%) demonstrated a delayed psychomotor development with an suboptimal neurological examination (mild delay n=3, severe delay n=2). Neurodevelopmental status did not correlate with pre-intrauterine transfusion hemoglobin, platelet, or blood pH values. Growth and general health status were normal in all. Two children had minor congenital defects. CONCLUSION: Neurodevelopmental status was abnormal in 5 of 16 survivors and was not related to the severity of fetal anemia and acidemia. We hypothesize that fetal parvovirus B19 infection may induce central nervous system damage. LEVEL OF EVIDENCE: III. 相似文献
77.
Stähler van Amerongen K Kuhn A Surbek D Nelle M 《Zeitschrift für Geburtshilfe und Neonatologie》2007,211(2):87-89
The current study demonstrates for the first time the presence of ear acupuncture points in prematurely delivered triplets of 31 weeks and two days gestational age. Pregnancy was an IVF pregnancy and caesarean section was performed because of preeclampsia. Ear acupuncture points were determined with the Svesa point selector 1070 and correlated well with the clinical state of the neonates meaning that the sickest child demonstrated the most active ear points. Psychotropic points were not found. For the future ear acupuncture points may be further used for diagnostics and therapy in neonates. 相似文献
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