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991.
Manfred Cejna Siegfried Thurnher Johann Pidlich Klaus Kaserer Maria Schoder Johannes Lammer 《Cardiovascular and interventional radiology》1999,22(4):305-310
Purpose: To investigate whether placement of a polyester-covered stent-graft increases the primary patency of transjugular intrahepatic
portosystemic stent shunts (TIPSS).
Methods: Between 1995 and 1997 Cragg Endopro or Passager MIBS stent-grafts were used for the creation of TIPSS in eight male patients,
35–59 years of age (mean 48 years). All patients suffered from recurrent variceal bleeding and/or refractory ascites due to
liver cirrhosis. Seven stent-grafts were dilated to a diameter of 10 mm, one to 12 mm. Follow-up was performed with duplex
ultrasound, clinical assessment, and angiography.
Results: The technical success rate for creation of a TIPSS was 100%. The mean portosystemic pressure gradient decreased from 25 mmHg
to 12 mmHg. In seven of eight patients TIPSS dysfunction occurred between 2 days and 3 years after stent-graft placement.
In one patient the TIPSS is still primarily patent (224 days after creation). The secondary patency rates are 31 days to 3
years.
Conclusion: The primary use of polyester-covered stent-grafts for TIPSS did not increase primary patency rates in our small series. 相似文献
992.
Simultane Radiochemotherapie mit Taxol/Carboplatin bei fortgeschrittenen operablen Kopf-Hals-Tumoren
Eckardt Andre Wildfang Ingeborg Karstens Johann H. 《Strahlentherapie und Onkologie》1999,175(3):11-13
Strahlentherapie und Onkologie - Die simultane Radiochemotherapie hat das Ziel, die lokoregionäre Tumorkontrolle zu erhöhen und die Rate an Fernmetastasen zu senken. Therapieregime, die... 相似文献
993.
Mandana Neu Christian Strauss Johann Romstöck Barbara Bischoff Rudolf Fahlbusch 《Clinical neurophysiology》1999,110(11):1935-1941
Based on a consecutive series of 70 hearing patients with unilateral acoustic neurinomas and intraoperative monitoring of brain-stem auditory evoked potentials (BAEP), 4 dynamic BAEP patterns could be characterized. These patterns correspond with early and late postoperative hearing outcome. All patients with stable wave V (pattern 1) showed definite hearing preservation, all patients with irreversible abrupt loss of BAEP (pattern 2) lost their hearing, despite early hearing preservation in two cases. All patients with irreversible progressive loss of either wave I or wave V (pattern 3) eventually suffered from definite postoperative hearing loss, despite early hearing preservation in two cases. Those cases with intraoperative reversible loss of BAEP (pattern 4) showed variable short and long term hearing outcome. In 34% hearing was preserved, 44% suffered from postoperative hearing loss, the remaining 22% showed postoperative hearing fluctuation, either as a delayed hearing loss or as reversible hearing loss. Postoperative hearing fluctuation indicates anatomical and functional preservation of the cochlear nerve during surgery and is suggestive of a pathophysiological mechanism initiated during the surgical procedure and continuing thereafter. Patients at risk for delayed hearing loss can be identified during surgery by a characteristic BAEP pattern and may benefit from vasoactive treatment. 相似文献
994.
Gasteiger Johann Pförtner Matthias Sitzmann Markus Höllering Robert Sacher Oliver Kostka Thomas Karg Norbert 《Perspectives in Drug Discovery and Design》2000,20(1):245-264
In combinatorial chemistry, hundreds of thousands of reactions are run in parallel, on beads, or simultaneously in solution.
A careful planning of these reactions is therefore of paramount importance in order to influence the products obtained in
these experiments. We present here three software systems that should assist the chemist in solving problems metin combinatorial
chemistry: WODCA can be used for the planning of the synthesis of combinatorial libraries. EROS is designed to model the course
of chemical reactions to predict their products. CORA is a tool to analyze series of reactions such as those contained in
reaction databases to derive knowledge that can be used in designing and simulating chemical reactions.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
995.
Hilde van den Brink Doeschka A Ferro Jeroen de Bresser Esther E Bron Laurien P Onkenhout L Jaap Kappelle Geert Jan Biessels Heart-Brain Connection Consortium 《Journal of cerebral blood flow and metabolism》2021,41(10):2690
Cerebral cortical microinfarcts (CMI) are small ischemic lesions that are associated with cognitive impairment and probably have multiple etiologies. Cerebral hypoperfusion has been proposed as a causal factor. We studied CMI in patients with internal carotid artery (ICA) occlusion, as a model for cerebral hemodynamic compromise. We included 95 patients with a complete ICA occlusion (age 66.2 ± 8.3, 22% female) and 125 reference participants (age 65.5 ± 7.4, 47% female). Participants underwent clinical, neuropsychological, and 3 T brain MRI assessment. CMI were more common in patients with an ICA occlusion (54%, median 2, range 1–33) than in the reference group (6%, median 0; range 1–7; OR 14.3; 95% CI 6.2–33.1; p<.001). CMI were more common ipsilateral to the occlusion than in the contralateral hemisphere (median 2 and 0 respectively; p<.001). In patients with CMI compared to patients without CMI, the number of additional occluded or stenosed cervical arteries was higher (p=.038), and cerebral blood flow was lower (B −6.2 ml/min/100 ml; 95% CI −12.0:–0.41; p=.036). In conclusion, CMI are common in patients with an ICA occlusion, particularly in the hemisphere of the occluded ICA. CMI burden was related to the severity of cervical arterial compromise, supporting a role of hemodynamics in CMI etiology. 相似文献
996.
Kimihiro Yoshimura Laurence Przybilla Shunji Ito Johann Diedrich Brand Mike Wehmeir Hans Joachim Rder Klaus Müllen 《Macromolecular chemistry and physics.》2001,202(2):215-222
Polycyclic aromatic hydrocarbons (PAHs) with high molecular weights represent a class of compounds which are difficult to analyze with conventional analytical methods because of their insolubility. In this paper, we describe their characterization by laser desorption mass spectrometry (LDMS). The huge PAHs show a fragmentation pathway which is unknown so far. It can be explained by the loss of cyclic C6‐units and a subsequent rehydrogenation of the resulting radical sites of the measured fragments. With these findings we are able to detect structure defects in a PAH induced by rearrangement reactions during synthesis. Since the analysis of large PAHs by LDMS is generally hindered by the formation of fragments we also developed an improved method of sample preparation analogous to matrix assisted laser desorption/ionization (MALDI) mass spectrometry. By this method, the isotopic distribution of the PAH molecular ions can now be measured without interfering signals of fragments to enable a reliable identification. 相似文献
997.
C Cafri B de la Guardia E Barasch J Brink R W Smalling 《Catheterization and cardiovascular interventions》2000,50(4):463-467
Positioning of the transseptal needle during percutaneous transvenous mitral commissurotomy (PTMV) can become a difficult and risky procedure when distortion of the interatrial septum exists. We present two cases where intracardiac echocardiography (ICE) facilitated the transseptal puncture in the presence of bulging of the fossa ovalis into the right atrium. 相似文献
998.
Stephan E. Baldus Thomas K. Zirbes Sabine Engel Franz-Georg Hanisch Stefan P. Mnig Johann Lorenzen Jan Glossmann Susanne Fromm Jürgen Thiele Heinz Pichlmaier Hans P. Dienes 《International journal of cancer. Journal international du cancer》1998,79(2):133-138
The expression of MUC1 and MUC2 mucin peptide core antigens in gastric carcinomas was studied by immunohistochemistry to determine correlations with TNM stage and histo-pathological classifications as well as a possible prognostic impact. Paraffin-embedded specimens from 128 gastric carcinomas with a minimal follow-up of 5 years were immunostained. In addition to a polyclonal antiserum generated against polymorphic epithelial mucin (MUC1) from human milk, 2 monoclonal antibodies (MAbs), HMFG2 (anti-MUC1) and 4F1 (anti-MUC2), were applied. Reactivity of carcinomas was correlated with the classifications of the UICC (TNM), WHO and Laurén. Correlations with overall survival were analyzed using the Kaplan and Meier product limit method. MUC1 immunoreactivity was associated with an advanced pTNM stage. The demonstration of both mucin species (MUC1, MUC2) displayed a statistically significant correlation with tubular/papillary vs. signet-ring cell differentiation as well as with intestinal-type vs. diffuse-type of tumor growth according to Laurén. In particular, MUC2 was only rarely detectable in signet-ring cell and diffuse-type tumors. MUC1 correlated with poor prognosis in all cases and the subgroup of stage I tumors. According to the histopathological classifications, a similar result was observed in signet-ring cell and diffuse-type carcinomas. In contrast, MUC2 reactivity was associated with a favourable prognosis of intestinal-type carcinomas. In the non-neoplastic gastric mucosa, both peptide cores were recognized in the superficial epithelium, whereas parietal cells contained only MUC1, and intestinal metaplasia almost exclusively MUC2 antigens. We conclude that the mucin peptide core antigens are suitable markers for the tubule-rich gastric carcinomas, which may in part be derived from intestinal metaplasia. In addition, MUC1 may exert a prognostic relevance and appears to be involved in the progression of diffuse-type tumors. Int. J. Cancer (Pred. Oncol.) 79:133–138, 1998.© 1998 Wiley-Liss, Inc. 相似文献
999.
1000.
Runjan Chetty Mahomed A. Dada Chris H. Boshoff Margaret A. Comley Simon C. Biddolph Johann W. Schneider David Y. Mason Karen A. Pulford Kevin C. Gatter 《The Journal of pathology》1997,181(3):311-315
The distribution of TAL-1 protein, an important vascular promoter in mice, has been examined immunohistochemically in a range of human vascular lesions and normal tissues. Formalin-fixed, paraffin-embedded vascular lesions including granulation tissue, haemangiomas, Kaposi's sarcomas, spindle cell haemangioendotheliomas, and angiosarcomas, were examined using a monoclonal antibody to recombinant TAL-1. Endothelial cells in all lesions gave positive immunostaining of variable intensity. Granulation tissue and spindle cell areas of the vascular tumours gave the strongest staining (nuclear and cytoplasmic). The better-differentiated endothelial cells within the tumours and resident well-formed vessels were less positive and some cells were in fact negative. The malignant endothelial cells in angiosarcomas showed less intense positive staining than KS cells. This study has shown TAL-1 protein expression in a range of reactive, benign, and malignant vascular lesions. Protein expression appears to be stronger in the spindle cell areas, perhaps reflecting greater expression in less-differentiated endothelial cells. © 1997 John Wiley & Sons, Ltd. 相似文献