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排序方式: 共有1129条查询结果,搜索用时 15 毫秒
1.
M Engelhardt P Bast N Jeblink W Lauer A Popovic H Eufinger M Scholz A Christmann A Harders K Radermacher K Schmieder 《Minimally invasive neurosurgery》2006,49(2):98-103
This study was performed to evaluate the surgical strategy in patients with calvarial tumours, in order to design and modify a robot-assisted trepanation system. A total of 75 patients underwent craniectomy for the treatment of calvarial tumours during the 10-year period from 1993 to 2002. The patients' complaints, the size, location and histology of the tumour, and the various cranioplasty techniques used were analysed retrospectively. In a second procedure several craniectomies at typical locations according to the study's results were performed in a laboratory setting using a hexapod robotic tool, constructed at the Helmholtz-Institute, RWTH Aachen University, and plastic model heads. The workflow was documented and the reproducibility and the accuracy of the procedure were registered. A total of 83 surgical procedures were performed on 75 patients. The majority (87 %) of lesions treated surgically were located in the frontal, temporal and anterior parts of the parietal region. Histological examination revealed benign lesions in 66 % of the patients and dural involvement in 46 %. According to these results craniectomies were performed using the robotic system. Mean positioning accuracy of the robotic system while milling was 0.24 mm, with a standard deviation of 0.04 mm, and maximum error under 1 mm. Craniectomies leaving a 1-mm layer of the tabula interna intact to ensure a healthy dura were performed in several regions successfully. The majority of calvarial tumours, requiring surgical treatment in our patients, were located in cosmetically relevant areas in which drilling can be carried out with the robotic trepanation system. Consequently, the surgical approach had to be planned carefully in order to achieve a good cosmetic outcome. 相似文献
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The magnetic resonance (MR) images of six patients with thrombosis of a dural sinus were reviewed. The diagnosis had been verified by computed tomographic scans in three patients and arteriograms in two; in the sixth patient, only MR imaging was used to confirm the clinical syndrome. In all patients, high-intensity signal was seen from the thrombus within the affected dural sinus on all echoes. This persistent signal intensity allowed intravascular clot to be distinguished from normal causes of increased signal such as flow-related enhancement (entry phenomenon) and even-echo rephasing. MR imaging demonstrated the cause of the thrombosis in three patients: two were secondary to adjacent tumors, and one was secondary to unsuspected mastoiditis. Complications such as infarction were also demonstrated. Using MR imaging, one can easily and safely diagnose thrombosis of a dural sinus. MR should be the imaging method of choice in patients suspected of having thrombosis of a dural sinus. 相似文献
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BACKGROUND. Although the ascites of patients with ovarian cancer has been reported to contain immunosuppressive factors, the identity and source of this activity has not been determined. Previously, the authors showed that conditioned media from two of four epithelial ovarian cancer cell lines inhibits proliferation of mitogen-stimulated human lymphocytes. The physical characteristics of the inhibitory substance are unlike those of peptide growth factors but closely resemble those of fibronectin. METHODS AND RESULTS. In the current study, it was found that the two ovarian cancer cell lines that produce the inhibitory substance have more fibronectin on the cell surface and secrete significantly more immunoreactive fibronectin into their culture media than the other two ovarian cancer cell lines. In addition, the immunosuppressive activity was bound to a gelatin-Sepharose affinity column, known to bind fibronectin. Finally, in ascites from 20 patients with advanced epithelial ovarian cancer, fibronectin levels correlated with the ability to inhibit proliferation of lectin-stimulated lymphocytes (P < 0.001). CONCLUSIONS. Fibronectin is produced by some ovarian cancer cell lines and acts to inhibit proliferation of mitogen-stimulated lymphocytes. Additional studies are needed to clarify the role of fibronectin in ovarian cancer. 相似文献
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Limited-field-of-view radio-frequency receiver antennas provide improved near-field sensitivity for magnetic resonance imaging by decreasing the antenna volume. The Helmholtz-type surface coil, consisting of two flat rings, is an organ-encompassing antenna that takes advantage of this principle to yield an improved signal-to-noise ratio (S/N). The coil was tested in a group of 50 patients and 16 healthy volunteers. Images obtained with the Helmholtz coil demonstrated quantitatively superior S/N of 2.2-fold or greater than that of comparison body coil images, as well as qualitatively superior anatomic resolution. 相似文献
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Prof. Dr. Bernhard Schmitt Prof. Dr. Michael Albani Priv.-Doz. Dr. Thomas Bast Prof. Dr. Ulrich Brandl Prof. Dr. Rudolf Korinthenberg Prof. Dr. Gerhard Kurlemann Prof. Dr. Bernd Neubauer Prof. Dr. Ulrich Stephani Dr. Markus Wolff 《Zeitschrift für Epileptologie》2007,20(3):113-119
Zusammenfassung
Der richtige Zeitpunkt für das Absetzen der Antiepileptika (AE) im Kindesalter ist unbekannt. Anl?sslich ihrer Jahrestagung
haben die Mitglieder des K?nigsteiner Arbeitskreises (KA) eigene und publizierte Absetzstrategien diskutiert. Da Studien zu
diesem Thema rar und widersprüchlich sind, wurde beschlossen, die Diskussionsergebnisse im Sinne einer Meinungs?u?erung zu
publizieren.
Bei Neugeborenen besteht übereinstimmung, AE innerhalb von 2 bis 12 Wochen nach dem letzten Anfall abzusetzen. Bei BNS-Epilepsie
wird Vigabatrin nach 6 bis 12 und Sultiam nach 6 bis 36 Monaten abgesetzt. Nach erfolgreicher Steroidtherapie setzt die Mehrheit
des KA die AE-Therapie für zwei Jahre fort. Für die Rolando-Epilepsie sind 1 bis 3 Jahre Anfallsfreiheit ausreichend, auch
wenn fokale Spike-Waves persistieren. Im Falle einer symptomatisch fokalen Epilepsie ist die Grunderkrankung mitentscheidend
für das Absetzen. Die Behandlung der Absencen-Epilepsie kann nach zwei Jahren beendet werden, w?hrend bei myoklonisch- astatischer
Epilepsie meist eine 2- bis 5-j?hrige Anfallsfreiheit vorausgesetzt wird. Konsens besteht darüber, dass die Juvenile- Myoklonus-Epilepsie
ein sehr hohes Rückfallrisiko birgt. Dennoch ziehen einzelne neurop?diatrische Mitglieder einen Absetzversuch nach 2- bis
3-j?hriger Anfallsfreiheit in Betracht. Die überwiegende Mehrheit des KA führt aber bei gesicherter Diagnose keinen Absetzversuch
durch. Bezüglich der Absetzgeschwindigkeit wird ein langsames (3 bis 12 Monate) Ausschleichen favorisiert. Nur zwei Mitglieder
praktizieren ein rascheres Absetzen (<3 Monaten). Das EEG spielt für die Entscheidung eine untergeordnete Rolle und bleibt
auf bestimmte Epilepsieformen (z. B. Absencen-Epilepsie) beschr?nkt.
Das vorliegende Papier gibt die Meinung des KA wieder und eignet sich nicht im Sinne einer Leitlinie. Für die Entscheidung
AE abzusetzen, ist immer eine individuelle Abw?gung von Grunderkrankung, Epilepsieform und psychosozialen Umst?nde erforderlich.
相似文献
8.
S Wu K Rodabaugh O Martinez-Maza J M Watson D S Silberstein C M Boyer W P Peters J B Weinberg J S Berek R C Bast 《American journal of obstetrics and gynecology》1992,166(3):997-1007
OBJECTIVE: We investigated whether monocyte-derived factors could stimulate the growth of ovarian cancer cells. STUDY DESIGN: Human peripheral blood monocytes or human monocyte-like cell lines THP-1 and U-937 were cultured with or without macrophage colony-stimulating factor, lipopolysaccharide, or phorbol myristate acetate. Culture supernatants or recombinant cytokines were assayed for growth stimulation of ovarian cancer cell lines by tritium-thymidine incorporation and direct cell counts followed by statistical analysis with Student t test. RESULTS: Conditioned medium from peripheral blood monocytes or from THP-1 or U-937 cells stimulated ovarian cancer cell growth. Interleukin-1 alpha, tumor necrosis factor-alpha, and interleukin-6 also stimulated ovarian cancer cell growth, whereas macrophage, granulocyte, and granulocyte-macrophage colony-stimulating factor did not. Concentrations of tumor necrosis factor, interleukin-1, and interleukin-6 in conditioned medium could not account for all the growth stimulation, and activity remained after neutralization of tumor necrosis factor, interleukin-1, and interleukin-6 with antibodies. CONCLUSIONS: Interleukin-1, interleukin-6, tumor necrosis factor, and additional monocyte factor(s) could provide paracrine growth stimulation when monocytes are attracted to ovarian cancers that produce macrophage colony-stimulating factor. 相似文献
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