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41.
42.
Bernard–Soulier syndrome (BSS) is a rare autosomal recessively inherited bleeding disorder. Pregnancy in patients with BSS is characterized by ante‐, intra‐, or postpartum haemorrhage, which may be delayed and severe. There is no consensus in the management of BSS in pregnancy and so far only 16 pregnancies in nine patients have been described. We report a further three pregnancies in two women with the syndrome. We also outline our management of pregnant patients with BSS. 相似文献
43.
Riemer H J A Slart Ali Agool Dirk J van Veldhuisen Rudi A Dierckx Jeroen J Bax 《Journal of nuclear medicine》2006,47(8):1307-1311
SPECT with 99mTc-labeled agents is better able to detect viability after nitrate administration. Nitrates induce vasodilation and may increase blood flow to severely hypoperfused but viable myocardium, thereby enhancing tracer delivery and improving the detection of viability. Quantitative data on the changes in blood flow are lacking in SPECT but can be provided by PET. The aim of the present study was to use PET to evaluate whether nitrate administration increases blood flow to chronically dysfunctional but viable myocardium. METHODS: 13N-Ammonia PET was used to quantitatively assess blood flow, and 18F-FDG PET was used as the gold standard to detect viable myocardium. Twenty-five patients with chronic ischemic left ventricular dysfunction underwent 13N-ammonia PET at rest and after nitrate administration. RESULTS: A significant increase in nitrate-enhanced blood flow was observed in viable segments (from 0.55 +/- 0.15 to 0.68 +/- 0.24 mL/min/g, P < 0.05). No statistically significant change in blood flow was observed in nonviable segments (0.60 +/- 0.20 vs. 0.55 +/- 0.18 mL/min/g). A ratio of at least 1.1 for nitrate-enhanced flow to resting flow allowed optimal detection of viable myocardium, yielding a sensitivity of 82% with a specificity of 100%. CONCLUSION: 13N-Ammonia PET showed a significant increase in nitrate-enhanced blood flow in viable myocardium, whereas blood flow remained unchanged after nitrate administration in nonviable myocardium. Nitrate use during myocardial perfusion imaging will lead to improved assessment of myocardial viability. 相似文献
44.
ZusammenfassungHintergrund Bedingt durch die intraoperative Katecholaminsekretion mit hämodynamischen Veränderungen, einem größeren Tumordurchmesser und einer deutlichen Neovaskularisation ist die Adrenalektomie beim Phäochromozytom im Vergleich zu anderen Nebennierenerkrankungen schwieriger und potenziell komplikationsträchtiger. Ziel unserer Studie war die Frage, ob das Risiko intraoperativer kardiovaskulärer Komplikationen durch das minimal-invasive Vorgehen potenziert wird.Patienten und Methodik Im Zeitraum zwischen Februar 1992 und Mai 2005 wurden in unserer Klinik 82 Eingriffe wegen eines Phäochromozytoms bei 71 Patienten durchgeführt. Davon wurden 8 (1) Patient(en) bi-(tri-)lateral adrenalektomiert und bei 2 Patienten erfolgte eine ipsilaterale Rezidivoperation. Eingeschlossen sind 5 weitere Patienten mit Rezidiv nach Erstoperation vor 1992. Sechsunddreißig Eingriffe erfolgten konventionell (transperitoneal n=35, retroperitoneal n=1) und 46 Operationen endoskopisch (transperitoneal n=28, retroperitoneal n=18), davon keine Konversion zum offenen Vorgehen.Ergebnisse Das mediane Alter zum Zeitpunkt der Operation betrug 45 (24–75) Jahre bei einer Anamnesedauer von 12 (0–180) Monaten. Die offen operierten Phäochromozytome waren mit 5,5 (1–19) cm vs. 3,5 (0,5–8) cm (endoskopisch) signifikant größer (p=0,0011). Patienten mit endoskopischer, insbesondere mit retroperitoneoskopischer Adrenalektomie hatten im Vergleich zum konventionellen Vorgehen intraoperativ höhere systolische und diastolische maximale Blutdruckwerte sowie Spitzen über 200 mmHg (statistisch nicht signifikant). Faktoren mit möglichem Einfluss auf intraoperative hämodynamische Veränderungen waren in der multivariaten Analyse das Geschlecht (p=0,0107), der operative Zugangsweg (p=0,0153), das Patientenalter (p=0,0364) und die Tumorgröße (p=0,0484). Die postoperative stationäre Verweildauer war nach endoskopischer Operation signifikant kürzer (p<0,0001).Schlussfolgerung Die endoskopische Adrenalektomie beim Phäochromozytom ist in der Routine ohne vermehrtes Risiko kardiovaskulärer Komplikationen die Methode der Wahl. Das offene Vorgehen sollte extraadrenalen Befunden oder sehr großen Tumoren mit Malignitätsverdacht vorbehalten bleiben. 相似文献
45.
46.
Jan Jozef Braszko Anna Walesiuk Przemyslaw Wielgat 《Journal of the renin-angiotensin-aldosterone system》2006,7(3):168-174
This study tests the hypothesis that the facilitation of learning and improvement of memory observed after an intracerebroventricular (i.c.v.) injection of angiotensin II (Ang II) is, in fact, caused by its derivative angiotensin IV (Ang IV). We ran two memory tests as well as an auxiliary test assessing motor performance in rats injected (i.c.v., 1 nmol in 2 microl saline) with Ang II or Ang IV. There were separate groups receiving peptide or saline five, 10 and 15 minutes before testing. Ang IV significantly increased step-through latencies in a passive avoidance paradigm as well as improved discrimination between familiar and unfamiliar objects in an object recognition test in all groups showing better retrieval of memory of aversive as well as appetitive stimuli in the peptide-treated groups regardless of the time of its injection. In contrast, rats treated with Ang II demonstrated significant improvement of memory of aversive and appetitive stimuli in the same tests only 15 minutes after its i.c.v. injection, with no effect in the groups injected five minutes before testing and slight efficacy in those injected 10 minutes before the test. Numbers of crossings, rearings and bar approaches in an open field were similar both in the peptide-treated and control groups making it unlikely that changes in motor performance affected the memory tests. In line with the present views on the intracellular metabolism of Ang II, these results suggest degradation to Ang IV by aminopeptidases A and N is necessary before the cognitive effects can occur. 相似文献
47.
48.
49.
Barry L Eppley A Michael Sadove David Hennon John A van Aalst 《The Cleft palate-craniofacial journal》2006,43(3):374-378
OBJECTIVE: A series of nasopharyngeal appliance designs is presented that represents our evolving experience over a 20-year period in the adjunctive use of prosthetic stents in the surgical correction of nasopharyngeal stenosis. DESIGN: Retrospective assessment of effectiveness of two nasopharyngeal stenosis hollow stent designs in a consecutive series of patients for relief of nasal obstructive symptoms. SETTING: Tertiary academic medical center, Craniofacial Program at Children's Hospital. PATIENTS: Four patients with nasopharyngeal stenosis were treated with a preoperatively fabricated stent made from a clasped palatal appliance onto which hollow acrylic conduits were extended through surgically re-created pharyngeal ports. A subsequent set of four patients with nasopharyngeal stenosis were treated with intraoperatively-fashioned silastic grommets, as opposed to palatal appliances. INTERVENTIONS: Postoperative intraoral stenting of nasopharyngeal ports. MAIN OUTCOME MEASURES: Maintenance of pharyngeal port opening after 1 year, improvement in nasal airway obstructive symptoms. RESULTS: The palatal appliance stents were less well tolerated and had a lower maintenance of port patency after device removal (4 of 8, 50%). The silastic grommets provided better retention into the ports and increased patient tolerance, as well as better 1-year port maintenance (6 of 8, 75%). CONCLUSIONS: The grommet stent appliance offers numerous advantages over a conventional dental-clasped appliance for prosthetic nasopharyngeal stenting, including obviation of extensive preoperative preparation, ease of insertion and removal, and exchange of air during the stenting period. Improved nasopharyngeal patency with this device may be due to greater patient tolerance and subsequent longer use. 相似文献
50.
Steven V Koenen Anjoke J M Huisjes Jules Dings Yolanda van der Graaf Gerard H A Visser Hein W Bruinse 《The journal of maternal-fetal & neonatal medicine》2006,19(2):93-99
OBJECTIVE: To determine if there is a diurnal pattern in the clinical symptoms of HELLP (Hemolysis, Elevated Liver enzymes, Low Platelets) syndrome. STUDY DESIGN: A retrospective study was performed in 134 pregnancies complicated by HELLP syndrome. The medical records were reviewed to describe each HELLP episode. Time of day was divided into three periods, day, evening, and night. The following parameters were categorized according to the time of day: onset of symptoms, consultation by the doctor, initial blood sampling, diagnosis and decrease of symptoms. Biochemical parameters at clinical presentation and consecutive changes within 24 h were recorded. RESULTS: In 65 pregnancies 77 HELLP episodes were well documented. Times of onset of symptoms and consultation by the doctor were significantly higher during the evening and night (p < 0.001), whereas times of diagnosis and decrease of symptoms occurred significantly more during the day (p < 0.001). In only 49.3% of the cases were diagnostic laboratory criteria met at clinical presentation. This was mainly due to platelet values in excess of 100 x 10(9)/l. Several hours later (median 8 h, range 2-23) the decrease in platelets occurred. CONCLUSIONS: A diurnal pattern exists in the clinical symptoms of HELLP syndrome that is characterized by an exacerbation during the night and recovery during the day. There is a considerable delay between the onset of symptoms and the fulfillment of diagnostic laboratory criteria. 相似文献