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51.
Die Einheilung von autologer Beckenkammspongiosa in einem durch Plattenosteosynthese stabilisierten Kontinuitätsdefekt eines Röhrenknochens wurde an 20 erwachsenen Boxerhunden unter Verwendung der Semidünnschnittechnik untersucht. Die Durchsicht der Semidünnschnitte des transplantierten Knochengewebes, welches 1, 2, 4 und 8 Wochen nach der Transplantation entnommen wurde, ergab folgende Ergebnisse:
1.  Nach 1 Woche sind zwischen den transplantierten Spongiosabälkchen Anteile des reticulären Grundgewebes des roten Knochenmarkes mit verzweigten Mesenchymzellen und Hämocytoblasten zu erkennen, welche die Transplantation überlebt haben. Auffällig ist eine große Anzahl von Osteoblasten, die zum Teil rosettenartig angeordnet sind. Nekrosen oder Makrophagen sind nicht nachweisbar.
2.  2–4 Wochen postoperativ nimmt die Osteoblastenaktivität deutlich zu, und es findet sich entlang der Grenzfläche zwischen dem Transplantat und der angrenzenden Corticalis eine Schicht neugebildeter Knochengrundsubstanz, welche auffallend dicker ist als der gleichzeitig an die verpflanzten Spongiosabälkchen angelagerte Osteoidsaum.
3.  Nach 8 Wochen kommt es neben der Osteoblastentätigkeit auch zu einer vermehrten Osteoclastenaktivität, die sich an der Transplantat-Corticalis-Grenzfläche konzentriert und welche offensichtlich die Voraussetzungen für eine zunehmend festere Verzahnung des Transplantates mit dem aufnehmenden Knochen schafft.
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52.
Naproxen‐2‐nitrooxyethylester (S‐(+)‐2‐(6‐methoxy‐2‐naphthyl)propanoic acid‐2‐nitrooxyethylester, LE‐EK06) was synthesized from naproxen and 2‐nitrooxyethylbromide as a novel nitric oxide–releasing derivative of naproxen. Molar equivalents of LE‐EK06 (6.93–27.73 mg/kg, p.o.) to naproxen dose‐dependently exhibited greater antinociceptive activity in comparison to naproxen in a writhing assay. The compound (5.54–22.18 mg/kg, p.o.) showed greater anti‐inflammatory activity at 2 h after as comparable to its effect at 4 h after carrageenan challenge in rats. Further, LE‐EK06 (9.45 mg/kg, p.o.) was more potent in the carrageenan‐evoked hyperalgesia. LE‐EK06 (11.09 mg/kg, p.o.) and naproxen (8.0 mg/kg, p.o.) showed a comparable inhibitory effect on exudate formation and migration of polymorphonuclear leukocytes (PMNs) in a carrageenan‐induced pleurisy test. Further, the compound (11.09 mg/kg, p.o.) significantly reduced myeloperoxidase activity in carrageenan‐treated paw and demonstrated significantly less gastrotoxicity in acute and chronic (21 days) studies. The scanning electron microscopy revealed that LE‐EK06 showed only mild gastric damage (slight disruption of mucus layer) in comparison to naproxen. The present study suggested that naproxen‐2‐nitrooxyethylester (LE‐EK06) represents a novel gastric sparing NSAID. Drug Dev. Res. 61:66–78, 2004. © 2004 Wiley‐Liss, Inc.  相似文献   
53.
Die Sentinel-Lymphknotenbiopsie (Sentinel-Node-Biopsie, SNB) ist ein diagnostisches Verfahren beim Mammakarzinom, mit dem der Nodalstatus durch selektive Entnahme und Untersuchung des (der) Lymphknoten mit der höchsten Wahrscheinlichkeit für eine Metastasierung bestimmt wird. Hauptziel der Methode ist eine vollständige Erfassung der Patientinnen mit Lymphknotenmetastasen sowie die Vermeidung von Morbidität durch eine Axilladissektion bei nodalnegativen Frauen. Aufgrund der hohen Übereinstimmung zwischen dem histologischem Status des Sentinel-Nodes und dem definitiven Nodalstatus (ermittelt durch konventionelle Axilladissektion) stellt sich immer mehr die Frage, ob und unter welchen Bedingungen die SNB als Routineverfahren für das axilläre Staging gelten kann.  相似文献   
54.
AIMS: Long acting subcutaneous testosterone pellets are of proved efficacy for the treatment of hypogonadal men, but have not been reported as a treatment modality in adolescent boys. Pharmacodynamic studies of subcutaneous testosterone release have shown prolonged normalisation of testosterone levels for at least four months. Administration of a long acting, safe, effective, and convenient form of treatment is desirable when life-long treatment is indicated. PATIENTS AND METHODS: Eighteen boys (aged 13.9-17.5 years at the start of treatment)-seven with primary hypogonadism, nine with secondary hypogonadism, and two boys being treated with testosterone for tall stature--were given testosterone pellets (8-10 mg/kg) every six months for 18 months. Height, weight, pubertal status, and psychosocial parameters were assessed and follicle stimulating hormone, luteinising hormone, testosterone, prolactin, and lipids were measured at 0, 1, 3, 6, 12, and 18 months. Bone age was measured at 0 and 12 months. RESULTS: In all boys growth velocity continued appropriately for bone age. Puberty continued to progress in all boys and in two boys the amount of virilisation exceeded that seen with previous treatment with intramuscular testosterone. After testosterone administration, follicle stimulating hormone and luteinising hormone suppressed incompletely in the boys with primary hypogonadism. Serum testosterone ranged from 4.3 to 26.7 nmol/l at three months to less than 10 nmol/l at six months after implantation. Prolactin and lipid levels were normal throughout the study. By report, there was an improvement in mood and emotional wellbeing. No pellet extrusions occurred in a total of 156 pellet insertions. CONCLUSIONS: All boys preferred this mode of testosterone administration to intramuscular injections. Long acting subcutaneous testosterone pellets are safe, efficacious, well tolerated, and convenient, and result in normal physical growth and improved psychological outlook in adolescent hypogonadal boys.  相似文献   
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We compared, in a double-blinded manner, the anesthetic maintenance and recovery properties of remifentanil with a clinically comparable fentanyl-based anesthetic technique in pediatric ambulatory surgical patients. Anesthesia was induced with either halothane or sevoflurane and nitrous oxide and oxygen. Patients were randomized (computer generated) to receive either remifentanil or fentanyl in a blinded syringe with nitrous oxide and oxygen in one of four possibilities: halothane/remifentanil, halothane/fentanyl, sevoflurane/remifentanil or sevoflurane/fentanyl. In patients receiving remifentanil, a placebo bolus was administered, and a continuous infusion (0.25 microg. kg(-1). min(-1)) was begun. In patients receiving fentanyl, a bolus (2 microg/kg) was administered followed by a placebo continuous infusion. The time from discontinuation of the anesthetic to extubation, discharge from the postanesthesia care unit (PACU), and discharge to home, as well as pain scores, were assessed by a blinded nurse observer. Systolic blood pressure and heart rate were noted at selected times, and adverse events were recorded. Remifentanil provided faster extubation times and higher pain-discomfort scores. PACU and hospital discharge times were similar. There were no statistical differences among the groups for adverse events. There were statistically, but not clinically, significant differences in hemodynamic variables. We noted that continuous infusions of remifentanil were intraoperatively as effective as bolus fentanyl. Although patients could be tracheally extubated earlier with remifentanil, this did not translate to earlier PACU or hospital discharge times. In addition, remifentanil was associated with higher postoperative pain scores. The frequent incidence of postoperative pain observed in the postoperative recovery room suggests that better intraoperative prophylactic analgesic regimens for postoperative pain control are necessary to optimize remifentanil's use as an anesthetic for children. Implications: This is a study designed to examine the efficacy and safety of a short-acting opioid, remifentanil, when used in pediatric patients. The frequent incidence of postoperative pain observed in the postoperative recovery room suggests that better intraoperative prophylactic analgesic regimens for postoperative pain control are necessary to optimize remifentanil's use as an anesthetic for children.  相似文献   
57.
Polygonum multiflorum stilbeneglycoside (PMS) is a water-soluble fraction of Polygonum multiflorum Thunb. , one of the most famous tonic traditional Chinese medicines, that has protective effects on the cardiovascular system. The purpose of the present study is to elucidate the effects of PMS on macrophage-derived foam cell functions and the reduction of severity of atherosclerosis in hypercholesterolemic New Zealand White (NZW) rabbits. NZW rabbits were fed for 12 weeks with a normal diet, a high cholesterol diet, or a high cholesterol diet associated with irrigation with different doses of PMS (25, 50, or 100 mg/kg). Treatment of NZW rabbits fed with high cholesterol diet with 100 mg/kg PMS attenuated the increase in plasma cholesterol, low-density lipoprotein cholesterol, very low-density lipoprotein cholesterol, and plasma triglyceride. Treatment with 50 and 100 mg/kg PMS caused 43% and 60% decrease in atherosclerotic lesioned area ratio to total surface area, respectively. In U937 foam cells, PMS could decrease the high expression of intercellular adhesion molecule (ICAM)-1 protein and the vascular endothelial growth factor (VEGF) protein levels in the medium induced by oxidized lipoprotein when analyzed by flow cytometry. The results proved that PMS is a powerful agent against atherosclerosis and that PMS action could possibly be through the inhibition of the expression of ICAM-1 and VEGF in foam cells.  相似文献   
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