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In accordance with increased proliferation in myeloproliferative neoplasm (MPN), the goal is to evaluate the immunoexpression of: β-catenin, PPAR-γ and Ki67 protein, to compare them with bone marrow ultrastructural characteristics in patients with MPN. Immunoexpression and electron microscopy of bone marrow was analyzed in 30 Ph-negative MPN patients, including per 10 patients with polycythemia vera (PV), essential thrombocythemia (ET) and primary myelofibrosis (PMF). The quantity of β-catenin immunoreactive cells was significantly higher in PV then in ET (p < 0.01) or PMF group of patients (p < 0.01) and also in ET versus PMF group of patients (p < 0.01). Erythroid lineage showed absent β-catenin staining without immunoreactivity in nucleus. In contrast, immunoreactivity for PPAR-γ was localized mostly in megakaryocytes and the highest number of PPAR-γ immunopositive cells was detected in PMF group of patients. In addition, the proliferative Ki67 index was significantly increased in the PMF and PV patients compared to patients with ET. Also, the megakaryocytes showed abnormal maturation in PMF group of patients as determined by ultrastructural analysis. These results indicated that PV dominantly expressed β-catenin and proliferation marker Ki67 in bone marrow, while PMF is linked preferentially to PPAR-γ immunopositive megakaryocytes characterized by abnormal maturation.  相似文献   
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Purpose: The aim of this study was to investigate the relationship between surgical techniques and implant macro‐design (self‐tapping/non‐self‐tapping) for the optimization of implant stability in the low‐density bone present in the posterior maxilla using resonance frequency analysis (RFA). Materials and Methods: A total of 102 implants were studied. Fifty‐six self‐tapping BlueSkyBredent® (Bredent GmbH&Co.Kg®, Senden, Germany) and 56 non‐self‐tapping Standard Plus Straumann® (Institut Straumann AG®, Waldenburg, Switzerland) were placed in the posterior segment of the maxilla. Implants of both types were placed in sites prepared with either lateral bone‐condensing or with bone‐drilling techniques. Implant stability measurements were performed using RFA immediately after implant placement and weekly during a 12‐week follow‐up period. Results: Both types of implants placed after bone condensing achieved significantly higher stability immediately after surgery, as well as during the entire 12‐week observation period compared with those placed following bone drilling. After bone condensation, there were no significant differences in primary stability or in implant stability after the first week between both implant types. From 2 to 12 postoperative weeks, significantly higher stability was shown by self‐tapping implants. After bone drilling, self‐tapping implants achieved significantly higher stability than non‐self‐tapping implants during the entire follow‐up period. Conclusions: The outcomes of the present study indicate that bone drilling is not an effective technique for improving implant stability and, following this technique, the use of self‐tapping implants is highly recommended. Implant stability optimization in the soft bone can be achieved by lateral bone‐condensing technique, regardless of implant macro‐design.  相似文献   
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This study assessed whether sleep-dependent changes in the relationship between heart period (HP) and mean arterial pressure (MAP) occur in newborn life. Electrodes for electrocorticographic, electromyographic, and electrooculographic monitoring and an arterial catheter for blood pressure recordings were implanted in 11 newborn lambs. HP and MAP beat-to-beat values were computed from 120-s blood pressure recordings during quiet wakefulness, active sleep, and quiet sleep. For each recording, the time shift at which the maximum of the HP versus MAP cross-correlation function was attained was identified. For each lamb and wake-sleep state, an average correlation coefficient was then computed corresponding to the median value of such time shifts. The maximum of the cross-correlation function was attained with HP lagging behind MAP. The corresponding mean correlation coefficient was significantly higher in quiet sleep (0.51 +/- 0.05) than either in quiet wakefulness (0.31 +/- 0.05) or in active sleep (0.29 +/- 0.03). Sleep-related differences in the correlation between HP and MAP were maintained after HP and MAP data were low-pass filtered at 0.3 Hz to remove their fast ventilatory oscillations. In conclusion, data indicate that the relationship between spontaneous fluctuations in HP and those in MAP is sleep-state dependent in newborn lambs. A positive HP versus MAP correlation with HP lagging behind MAP is consistent with baroreflex control of HP. Heart rhythm thus may be more tightly controlled by the baroreceptor reflex and less dependent on central autonomic commands in quiet sleep than either in quiet wakefulness or in active sleep.  相似文献   
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Abstract The surgical treatment of 30 cases of vascular thoracic outlet syndrome (TOS) in 25 patients is presented. Patients included 17 women and 8 men with average age of 26.1 years. The causes of compression were cervical rib (n = 16), soft tissue anomalies (n = 12), and scar tissue after clavicle fracture (n = 2). Ten subclavian artery aneurysms containing intraluminal thrombus as well as one subclavian artery occlusion were found. All such cases had multiple distal arterial embolization. Presenting features of cases with arterial TOS included: hand ischemia (n = 11), transient ischemic attack (TIA) (n = 1), and claudication or vasomotor phenomena during the arm hyperabduction (n = 11). Two patients with venous TOS developed hand edema during arm hyperabduction, and five other patients had axillary-subclavian venous thrombosis. In all cases decompressive procedures using a combined supraclavicular and infraclavicular approach were performed. Decompression was achieved by cervical rib excision (n = 12), combined cervical and first rib excision (n = 4), and first rib excision (n = 14). In all cases division of all soft tissue elements was also accomplished. Associated vascular procedures included resection and replacement of 10 subclavian artery aneurysms, one subclavian-axillary and one axillary-brachial bypass, as well as nine brachial embolectomies. All five cases with axillary-subclavian vein thrombosis before decompression were treated with anticoagulant therapy. The mean follow-up period was 3 years and 2 months (range 1 to 6 years). Two pleural entry injuries and two transient brachial plexus injuries were noted. All reconstructed arteries were patent during the follow-up period. Complete resolution of symptoms with a return to full activity was noticed in all cases with arterial TOS and in two cases with venous TOS without axillary-subclavian vein thrombosis. In cases with axillary-subclavian vein thrombosis relief of symptoms was mild, and there were limitations on daily activity. Vascular TOS is seen less frequently than the neurogenic form; however, in most cases it requires surgical treatment. We prefer a combined supraclavicular and infraclavicular approach because it offers complete exposure of the subclavian artery, cervical and first ribs, and all soft tissue anomalies. Electronic Publication  相似文献   
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Operationsprinzip Zementfreie Implantation eines kraftflu?orientierten Hüfttotal-Endoprothesensystems mit weitgehender Erhaltung der ?Substantia spongiosa?, welche die kraftübertragenden elastomechanischen und biodynamischen Elemente enth?lt. Die dauerhafte Verankerung der Endoprothesenpfanne geschieht über eine gro?fl?chige Integration in der Spongiosa am Acetabulum. Die Femurkomponente der Endoprothese besteht aus einer Tragplatte und verstrebten Pfeilern, die in der gesamten Trochanterregion verankert werden. Der Schenkelhals wird weitgehend erhalten. Die Vernetzung der Endoprothese in der Spongiosa, eine prim?re Rotationsstabilit?t und die Aufnahme von Zugkr?ften im Trochantermassiv erm?glichen eine ann?hernd physiologische Kraftübertragung am Hüftgelenk.   相似文献   
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