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101.
1. We looked for P2-purinoceptors modulating noradrenaline release in rat heart atria. Segments of the atria were preincubated with [3H]-noradrenaline and then superfused with medium containing desipramine (1 microM) and yohimbine (1 microM) and stimulated electrically, by 30 pulses/1 Hz unless stated otherwise. 2. The adenosine A1-receptor agonist, N6-cyclopentyl-adenosine (CPA; EC50 9.7 nM) and the nucleotides, ATP (EC50 6.6 microM) and adenosine-5'-O-(3-thiotriphosphate) (ATP gamma S; EC50 4.8 microM), decreased the evoked overflow of tritium. The adenosine A2a-agonist, 2-p-(2-carbonylethyl)-phenethylamino-5'-N-ethylcarboxamido-a denosine (CGS-21680; 0.03-0.3 microM) and the P2x-purinoceptor agonist beta, gamma-methylene-L-ATP (30 microM) caused no change. 3. The concentration-response curve of CPA was shifted to the right by the adenosine A1-receptor antagonist, 8-cyclopentyl-1,3-dipropyl-xanthine (DPCPX; 3 nM; apparent pKB value 9.7) but hardly affected by the P2-purinoceptor antagonist, cibacron blue 3GA (30 microM). In contrast, the concentration-response curves of ATP and ATP gamma S were shifted to the right by DPCPX (3 nM; apparent pKB values 9.3 and 9.4, respectively) as well as by cibacron blue 3GA (30 microM; apparent pKB values 5.0 and 5.1, respectively). Combined administration of DPCPX and cibacron blue 3GA caused a much greater shift of the concentration-response curve of ATP than either antagonist alone. The concentration-response curve of ATP was not changed by indomethacin, atropine or the 5'-nucleotidase blocker alpha, beta-methylene-ADP. 4. Cibacron blue 3GA (30 microM) increased the evoked overflow of tritium by about 70%.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
102.
Pericarditis constrictiva after cardiac surgery is rare and may occasionally lead to congestive heart failure. The case of a 29-year-old patient is described who presented with pericarditis constrictiva after aortic valve replacement with localized tamponade, causing functional tricuspid stenosis. Pericardiectomy as the treatment of choice was curative.  相似文献   
103.
104.
105.
There are relatively few effective clinical options for preserving female fertility, particularly following aggressive chemotherapy and/or radiotherapy treatment protocols. This document reviews scientific background, current technology, clinical results, and potential future applications of ovarian tissue cryopreservation and transplantation. The technology is investigational although rapidly evolving, and the list of appropriate indications may be expanded in the future. Germany stays abreast of these rapid worldwide developments by having founded the first German network of experts for fertility preservation in patients undergoing chemotherapy and/or radiotherapy.  相似文献   
106.
The aim of this orthopaedic-biomechanical study was to evaluate lower leg muscle function in ankle osteoarthritis (OA) patients and muscle rehabilitation after the implantation of a total ankle replacement (TAR). Patients with a severe unilateral ankle OA were assessed with an orthopaedic and biomechanical examination before and one year after TAR surgery. Visual analogue pain score, American Orthopaedic Foot and Ankle Society (AOFAS) ankle score, ankle range of motion for dorsi- and plantar flexion (ROM DF/PF), and calf circumference difference between affected and contralateral healthy leg were measured. Isometric maximal voluntary torque for ankle dorsiflexion and plantar flexion were measured simultaneously with surface electromyography (EMG; mean frequency and intensity) of the anterior tibial, medial gastrocnemius, soleus, and peroneus longus muscle. Data were compared to a group of age- and gender-matched normal subjects. The mean calf circumference difference between legs did not significantly decrease from preoperative to one year follow-up. The mean dorsiflexion torque and plantar flexion torque of the affected ankle increased significantly. The atrophic muscles were characterized by a reduction of the mean EMG intensity and mean EMG frequency. In the rehabilitation process, the mean EMG intensity recovered and was not significantly different for all muscles, however, not for EMG frequency, which remained low and unchanged. This study reports for the first time in the literature the clinical and biomechanical facts of lower leg muscle atrophy in ankle OA as well as the amount of the muscle rehabilitation after a total ankle replacement. Patients with a symptomatic ankle OA achieve better function with a total ankle replacement; however, one year after the operation neuromuscular and biomechanical deficits may still be present.  相似文献   
107.
Orale Zytologie     
Zusammenfassung Die orale Zytologie erf?hrt eine Renaissance, die durch die Einführung der Bürste als Entnahmetr?ger und durch die Anwendung zus?tzlicher moderner Verfahren bedingt ist. Die Bürste kann tiefe Schichten der oralen Mukosa erfassen, in denen die squam?se intraepitheliale Neoplasie (SIN) beginnt. Zus?tzliche Verfahren zur Bewertung der biologischen Potenz der gewonnenen oralen Epithelzellen sind: die computerunterstützte Bildanalyse (OralCDx?), die DNA-Zytometrie, die Immunzytochemie, die Dünnschichtzytologie und molekularbiologische Analysen. Alle genannten Verfahren sind geeignet, die Sensitivit?t (bis zu 100%) und Spezifit?t (bis zu 100%) der oralen Zytologie zu erh?hen. Dennoch gibt es Berichte über orale Plattenepithelkarzinome, die mithilfe der Bürstenbiopsie nicht erkannt wurden. Die Wertigkeit der einzelnen Verfahren kann aktuell aufgrund fehlender vergleichender Studien nicht abschlie?end beurteilt werden. Die Immunzytochemie mit kommerziellen Antik?rpern gegen Laminin 5 ist allseits verfügbar und methodisch einfach. Das nichtinvasive diagnostische Verfahren der methodisch unterstützten oralen Bürstenbiopsie kann einen Beitrag zur frühen Erkennung ausgew?hlter Mundschleimhautl?sionen leisten. Ein positiver Befund oder eine Progression der L?sion bei negativem Befund sind Indikationen zur überweisung des Patienten an Fachkliniken und zur dort durchgeführten Skalpellbiopsie mit histopathologischer Untersuchung. Die histopathologische Begutachtung bleibt der Goldstandard in der definitiven Diagnostik maligner oraler L?sionen.   相似文献   
108.
109.
OBJECTIVE: To examine fetal (FHR) and neonatal heart rate patterns following use of common oral antihypertensives in pregnancy. METHODS: A systematic review of randomized controlled trials (RCTs), observational studies (N >/= 6 women), and animal studies. Data were abstracted (two reviewers) to determine relative risk (RR) (or risk difference (RD) for low event rates) and 95% CI. RESULTS: Eighteen RCTs (1858 women), one controlled observational study (N = 22), and seven case series (N = 117) were reviewed. Most hypertension was pregnancy-induced (N = 14 studies). The FHR was assessed by cardiotocogram (CTG) (N = 17 studies (visual interpretation); 1 study (computerized CTG), or umbilical artery velocimetry (N = 4). Four studies examined neonatal heart rate. In placebo-controlled RCTs (N = 192 women), adverse FHR effects did not differ between groups [9/101 (drugs) vs. 7/91 (placebo); RD 0.02, 95% CI (- 0.06, 0.11); chi2 = 1.02]. In six drug vs. drug RCTs (295 women), adverse FHR effects did not differ between groups [29/144 (methyldopa) vs. 42/151 (other drugs); RR 0.72, 95% CI (0.49, 1.07); chi2 = 0.69]. In one labetalol vs. placebo trial, neonatal bradycardia did not differ between groups [4/70 (labetalol) vs. 4/74 (placebo); OR 1.06, 95% CI (0.26, 4.39)], while in three drug vs. drug RCTs, neonatal bradycardia was not observed (0/24 vs. 0/26). CONCLUSIONS: Available data are inadequate to conclude whether oral methyldopa, labetalol, nifedipine, or hydralazine adversely affect fetal or neonatal heart rate and pattern. Until definitive data are available, FHR changes cannot be reliably attributed to drug effect, but may be due to progression of the underlying maternal or placental disease.  相似文献   
110.
Several human organs are not capable of functional regeneration following a tissue defect and react with scar formation. In stem cell transplantation, undifferentiated or partly differentiated precursor cells are applied to defective tissue for therapeutic regeneration. After promising preclinical investigations, the transplantation of autologous stem cells for myocardial infarction treatment is being transferred to clinical use. Mesenchymal stem cells and endothelial precursor cells derived from the bone marrow or circulating blood as well as skeletal myoblasts are employed in clinical trials. Furthermore, indications for cell transplantation and delivery routes vary considerably throughout current investigations. Initial results suggest a potential for restoration of cardiac function in stem cell-treated patients; however, the mechanisms are not fully understood. This overview will focus on objectives, recent achievements, and future perspectives of diverse stem cell transplantation approaches.  相似文献   
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