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991.
Expression of cytokines and chemokines in cervical and amniotic fluid: relationship to histological chorioamnionitis. 总被引:1,自引:0,他引:1
Rose-Marie Holst Ricardo Laurini Bo Jacobsson Ellen Samuelsson Karin S?vman Christina Doverhag Ulla-Britt Wennerholm Henrik Hagberg 《The journal of maternal-fetal & neonatal medicine》2007,20(12):885-893
OBJECTIVE: To correlate cervical and amniotic fluid cytokines and macrophage-related chemokines to the development of histological chorioamnionitis (HCA) in patients with preterm labor (PTL) and preterm prelabor rupture of the membranes (PPROM). STUDY DESIGN: Cervical and amniotic fluid interleukin (IL)-6, IL-8, IL-18, monocyte chemotactic protein (MCP)-1, MCP-2, and MCP-3 from pregnant women (at 相似文献
992.
Polentarutti BI Peterson AL Sjöberg AK Anderberg EK Utter LM Ungell AL 《Pharmaceutical research》1999,16(3):446-454
Purpose. To clarify relations between alterations in electrical and permeability data with time and to elaborate accompanying structural changes of intestinal segments in Ussing chamber experiments.
Methods. Excised intestinal segments from the rat were studied in a modified Ussing chamber. Experiments were run up to 180 minutes during which the electrical parameters, PD, SCC, and R, were measured and the permeability coefficients (Papp) of mannitol and propranolol were determined. Each segment was observed under the light microscope for morphological evaluation.
Results. PD and SCC values showed a decrease for most segments while the R values remained steady throughout the experiment. The Papp for propranolol increased aborally to the small intestine. For mannitol, the reversed was observed. In some cases, there was a time-dependent change in permeability for these marker molecules. The main morphological changes observed were a decreased nucleo-apical distance, decreased villi amplification factor, initial edema, cell sloughing, and epithelial restitution.
Conclusions. The time-dependent changes in permeability coefficients of mannitol and propranolol are suggested to be related to changes in electrical parameters and morphological alterations. Presented data illustrates the importance of information regarding time-dependent structural changes for correct interpretation of permeability data. 相似文献
993.
Karin L. Dahlin Anette Mrtberg Lena Lstbom ke Ryrfeldt 《Basic & clinical pharmacology & toxicology》1999,85(Z2):288-293
Abstract We have previously shown that tricyclic antidepressants can induce vaso- and bronchoconstriction as well as oedema formation in isolated perfused lungs. This is an effect similar to that seen clinically in adult respiratory distress syndrome. In order to investigate whether endothelin can be a mediator of this reaction, isolated perfused rat lungs were exposed to 0.1 mM amitriptyline via the pulmonary circulation, perfusate was collected and endothelin-1 present in the perfusate and lavage fluids was determined by radioimmunoassay. A significant increase in perfusate concentration of endothelin-1 was noted, with the highest release seen within the first 10 min. of exposure. Histamine and thromboxane have also been proposed as mediators in induction of adult respiratory distress syndrome. However, no increased amounts of these mediators were detected in the perfusate. Experiments where lungs were exposed to exogenous endothelin-1 (0.1–1 nmol), both via the perfusate and via intratracheal instillation were conducted. Similar effects as observed with amitriptyline (0.1 mM) on lung function and perfusion flow were detected. In conclusion, the detection of endothelin-1 release in our lung model proposes a role for endothelin-1 in amitriptyline-induced vaso- and bronchoconstriction and possibly in adult respiratory distress syndrome type reaction. Further studies with this model are interesting in order to elucidate mechanisms behind the complex issue of adult respiratory distress syndrome-induction. 相似文献
994.
90% of preterm and 10% of mature neonates are reported to have increased tyrosine levels in blood and urine when fed certain cow's milk formulas which are relatively high in protein compared to human milk. It has been suggested that sustained raised tyrosine levels in early infancy might result in decreased intellectual functions at school age.We determined tyrosine by ion exchange and its parahydroxylated metabolites by gas chromatography as oxime-TMS derivatives. Mature neonates (n=30) on adapted cow's milk excreted significantly more (P<0.001) tyrosine, pHPLA, and pHPPA than control neonates (n=7) on human milk. Tyrosine levels in serum on adapted milk were high (17.5 vs. 6.6 Mol/100 ml) compared to human milk, as were pHPLA (7.6 vs. 3.7), pHPAA (1.8 vs. 0.3), and pHPPA (0.4 vs. nil). In prematures (850 to 2500 g, n=40) fed milk with a higher protein content (2.3 g/100 ml), the excretion of tyrosine and its metabolites was significantly raised (P<0.005) when compared to those on human milk (n=7). Excretion was highest in the lowest weight group (850 to 1500 g, n=10), and decreased with increasing birth weight. The low values reached on human milk were not reached by artificially fed prematures. In 5 small neonates (850 to 1700 g) who were followed continuously over the first 7 weeks of life, there were no significant changes in the excretion of tyrosine and its metabolites with increasing age and weight up to 2500 g.It is concluded that breast milk feeding in mature and premature newborns avoids an increase of tyrosine and its metabolites in serum with overspill into the urine. 相似文献
995.
Background: Combination treatment (chemoradiotherapy) is the standard treatment for locally advanced head and neck squamous cell carcinoma (HNSCC); however, treatment resistance and local recurrence are significant problems. A high level of epidermal growth factor receptor (EGFR) has been associated with a more aggressive phenotype as well as decreased responsiveness to radio‐ or chemotherapy. We examined the role of EGFR status and EGFR ligand expression for the treatment response. Methods: Intrinsic sensitivity to radiotherapy, cisplatin, and cetuximab treatments was investigated in 25 HNSCC cell lines. EGFR gene copy number, mRNA and protein expression, EGFR and Akt phosphorylation status, and mRNA expression of the EGFR ligands were analyzed using quantitative PCR and ELISA and assessed for their impact on treatment sensitivity. Results: Different treatment modalities yielded great diversity in outcome; of note, cetuximab treatment stimulated growth in one cell line. When treatments were combined primarily additive effects were observed. While radioresistance tended to be associated with a high level of phosphorylated EGFR (pEGFR; P = 0.09), cetuximab‐resistant cells had low levels of pEGFR (P = 0.13). The three most cetuximab‐sensitive cell lines had high EGFR gene copy numbers. Furthermore, cetuximab treatment response was significantly correlated with epiregulin mRNA expression (r = ?0.408, P = 0.043). Cisplatin‐resistant tumor cells expressed significantly lower levels of EGFR protein (P = 0.04) compared to cisplatin‐sensitive cells and tended to have lower levels of phosphorylated Akt (pAkt; P = 0.13) and lower expression levels of amphiregulin (P = 0.18). Conclusions: Epidermal growth factor receptor status and ligand expression influence the treatment sensitivity of HNSCC cells and may be useful as predictive markers. 相似文献
996.
Current and novel injectable hydrogels to treat focal chondral lesions: Properties and applicability
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Cecilia Pascual‐Garrido Francisco Rodriguez‐Fontan Elizabeth A. Aisenbrey Karin A. Payne Jorge Chahla Laurie R. Goodrich Stephanie J. Bryant 《Journal of orthopaedic research》2018,36(1):64-75
Focal chondral lesions and early osteoarthritis (OA) are responsible for progressive joint pain and disability in millions of people worldwide, yet there is currently no surgical joint preservation treatment available to fully restore the long term functionality of cartilage. Limitations of current treatments for cartilage defects have prompted the field of cartilage tissue engineering, which seeks to integrate engineering and biological principles to promote the growth of new cartilage to replace damaged tissue. Toward improving cartilage repair, hydrogel design has advanced in recent years to improve their utility. Injectable hydrogels have emerged as a promising scaffold due to their wide range of properties, the ability to encapsulate cells within the material, and their ability to provide cues for cell differentiation. Some of these advances include the development of improved control over in situ gelation (e.g., light), new techniques to process hydrogels (e.g., multi‐layers), and better incorporation of biological signals (e.g., immobilization, controlled release, and tethering). This review summarises the innovative approaches to engineer injectable hydrogels toward cartilage repair. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:64–75, 2018. 相似文献
997.
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999.
Caroline Möller Thomas C. Wetter Jürgen Köster Karin Stiasny-Kolster 《Sleep medicine》2010,11(2):161-166
BackgroundRestless legs syndrome (RLS) is a common neurological condition. We investigated the prevalence of RLS in patients suffering from unpleasant sensations in the legs.MethodsWe included 16,543 patients consulting one of 312 primary care practices in Germany on November 8, 2007. All patients filled out a self-assessment questionnaire. Patients who reported suffering from unpleasant sensations in the legs were then assessed by the physician. Main outcome measures were the overall prevalence of unpleasant sensations in the legs and the prevalence of RLS; the most common differential diagnoses in the subpopulation suffered from unpleasant leg sensations.ResultsOut of all participating patients 7704 (46.6%) suffered from unpleasant sensations in the legs and 1758 (10.6%) were diagnosed with RLS according to the four essential clinical criteria. Among patients with unpleasant leg sensations, the prevalence of RLS was considerably higher (22.7%) than in the total population. The most common differential diagnoses were osteoarthritis (21.5%), disc lesion (19.2%), varicose veins (18.8%) and muscle cramps (14.6%). Of the patients with RLS 53.4% had already consulted their physician about their leg problems in the past. Still, only 20.1% of the RLS patients had received the correct diagnosis. Comorbidity rates were significantly increased in RLS patients compared to patients suffering from leg symptoms of other origin.ConclusionsThis study showed a high prevalence of RLS in primary care patients with unpleasant sensations in the legs. Thus, in patients presenting with these symptoms the diagnosis of RLS should routinely be considered. 相似文献
1000.
Trauma und Berufskrankheit - Ambulantes Operieren ist bei mindestens gleich hoher Qualität kostengünstiger als eine stationäre Behandlung und wird im niedergelassenen Bereich immer... 相似文献