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71.
Johansson M Karauzum S Dietrich C Mandahl N Hambraeus G Johansson L Clausen P Mitelman F Heim S 《International journal of oncology》1994,5(1):17-26
Cytogenetic analysis of 114 adenocarcinomas of the lung revealed clonal abnormalities in 67 tumors. The chromosome numbers ranged from near-diploid to hypertetraploid. Clonal abnormalities seen as the sole anomaly were loss of the Y chromosome (21 tumors), trisomy 7 (2 tumors), and trisomy 12 (1 tumor). A supernumerary ring chromosome was the only clonal change in 4 tumors. The bands most often affected were 17p11-13 (13 cases), 1q10-12 and 1p22 (10 cases each), 1p11-13 and 1q21 (9 cases each), and 11p11, 11p15 and 15p11-13 (6 cases each). The chromosomes most frequently involved in structural rearrangements were chromosomes 1 (30 cases), 11 (20 cases), 3 (17 cases), 17 and 7 (16 cases each). Repeated loss of material from chromosome arms 1p, 3p, 6q, 11p, and 17p and gains of 1q were found. Recurrent structural changes were del(1)(p22) and i(5)(p10) (5 cases each) i(1)(q10), i(13)(q10), i(14)(q10) and del(17)(p11) (3 cases each). We found no abnormalities that seemed to be specifically associated with pulmonary adenocarcinomas, but isochromosomes i(1)(q10), i(5)(p10) and i(13)(q10) and changes of 6q were present in our series at frequencies higher than those generally seen in the other main types of lung cancer. 相似文献
72.
After two years clinical experience using an open 0.5 T-MRI, which make it possible to control all steps of a brain tumor resection, the high expense in relation to the effect is proofed. In 80 MRI-guided brain tumor resections the indication, the degree of resection, the appearance of operative induced changes, complications and clinical state are analysed. The advantage of the method consists in safety of localisation and detection especially of intra-axial cerebral tumors, recording of intraoperative invisible tumor parts and saving eloquent areas during tumor resection. To have optimal results, all over the operation time, the participation of a special experienced radiologist is necessary. The best results are shown in treatment of low grade gliomas and tumors near eloquent areas. 相似文献
73.
Schneider JP Dietrich J Lieberenz S Schmidt F Sorge O Trantakis C Seifert V Kellermann S Schober R Franke P 《European radiology》1999,9(2):230-236
The purpose of our study was to evaluate the feasibility and accuracy of brain biopsies performed within a vertically opened
MR system. We worked with the interventional 0.5-T MR “SIGNA SP” (General Electric Medical Systems, Milwaukee, Wis.) with
an integrated tracking device “Flashpoint Position Encoder” (Image Guided Technologies, USA). As a holding device for this
instrument we constructed a special frame. The whole system allows an exact adjustment of an optimum biopsy direction and
guidance of the biopsy in a non-stereotactic, interactive mode in near real-time. As biopsy tools we used MR-compatible aspiration
and specially made side-cut needles (Daum, Germany; E-Z-EM, USA). We performed a prospective diagnostic brain biopsy study
in 18 patients. Guidance of the needle was carried out using gradient-echo single-slice technique. The sample was taken after
controlling the exact position of the needle tip on spin-echo images. In 12 cases an exact neuropathological diagnosis was
possible. In 6 cases of negative biopsy (4 aspiration biopsies) the samples were not representative. Our results demonstrate
the feasibility of interactive MR-guided minimally invasive brain biopsies in an open MR system. The best results were achieved
using cut needles for biopsies of contrast-enhancing lesions visible on T1-weighted gradient-echo guidance sequence.
Received: 2 February 1998; Revision received: 13 July 1998; Accepted: 2 September 1998 相似文献
74.
A Bertalanffy W Dietrich M Aichholzer K Hittmair T Czech 《Journal of neurosurgery》1999,91(4):679-681
The authors describe the case of a 15-year-old boy who underwent resection of a large left temporal tumor. During a normal postoperative course, computerized tomography (CT) scanning demonstrated a spherically hyperdense structure near the internal carotid artery, enlarging on a control CT scan. A suspected false aneurysm was confirmed on magnetic resonance imaging; angiographic studies were negative. The authors believed they were dealing with a thrombosed false aneurysm and they performed operative revision. Intraoperatively the "aneurysm" could be dissected off the internal carotid artery and no lesion of the arterial wall was obvious. Histological findings showed a fresh blood clot. This case demonstrates that a blood clot may mimic an aneurysm on CT and magnetic resonance studies, which has not been described earlier. The origin of the blood clot remains unclear. 相似文献
75.
The Expression of the antiapoptotic oncoprotein BCL-2 and its correlation to tumor grade in 62 meningiomas (48 classic, 9
atypical, and 5 anaplastic) using single and double immunohistochemistry was investigated. BCL-2 expression was found in two
different cell populations identified as lymphocytes (BCL-2+CD3+) and tumor cells (BCL+/CD3–). Tumor-infiltrating lymphocytes
(TIL) (CD3+) were found within classic (9.5% of cells), atypical (2.4% of cells), and anaplastic (1.8% of cells) meningiomas.
In classic meningiomas, 66.5% of TIL were BCL-2-positive, in atypical meningiomas 79.2%, and in anaplastic meningiomas 37.9%.
In 33 (68.8%) of the classic meningiomas, medium to high counts of BCL-2+ tumor cells were detected. Atypical meningiomas
showed nearly equal percentages of high (two patients), medium (five patients), and low (two patients) BCL-2+ tumor cell counts,
whereas anaplastic meningiomas showed only medium (two patients) and low (three patients) BCL-2 tumor cell counts or were
BCL-2-negative (one patient). In summary, a significant inverse correlation between the number of BCL-2-positive tumor cells
and tumor grade in meningiomas was found. These findings support the hypothesis of cell survival prolongation by the antiapoptotic
ability of BCL-2 proto- oncogenes and demonstrate the prognostic relevance of BCL-2 immunoreactivity in meningiomas.
Received: 10 June 1998 / Accepted: 23 February 1999 相似文献
76.
77.
The occurrence of preferential repair in Saccharomyces cerevisiaeof the active MAT locus compared with the inactive HML locuswas confirmed after 254 nm UV irradiation. Experiments carriedout using the UvrABC excinuclease assay with the monofunctionalfurocoumarin 3-carbethoxypsoralen (3-CPs) plus UVA radiationwhich induce mainly monoadducts in DNA demonstrated preferentialrepair of the active MAT locus compared with the inactive HMLlocus in a SIR+ strain. However, as after 254 nm UV irradiation,no difference in the rate of removal of 3-CPs plus UVA inducedlesions was observed between the two loci in the sir-3 mutantin which both loci are active. Thus, it appears that 3-CPs plusUVA induced monoadducts as well as pyrimidine dinners a e subjectto preferential repair.
3To whom correspondence should be addressed 相似文献
78.
79.
Hans Christian Blossey Hans Helge Bartsch Dietrich Kanne Johannes Koebberling Gerhard Arno Nagel 《Cancer chemotherapy and pharmacology》1982,8(1):77-81
Summary Oral MPA 1.5 g/day leads to plasma concentrations between 1 and 12 g/ml, with a broad intra-and interindividual variance. The plateau state is reached in between 4 and 16 days. Plasma concentrations in the plateau state are very sensitive to dose modifications. After cessation of administration, the decline in plasma levels seems to proceed in two phases, with half-times of about 20 h and 4 days. Extraction procedures reveal no benefit in discriminating between MPA and its metabolites. 相似文献
80.
We describe two patients with subarachnoid haemorrhage due to a ruptured intracranial aneurysm and severe symptomatic vasospasm.
The aneurysm was occluded with detachable coils followed by intra-arterial infusion of papaverine to treat vasospasm as an
one-stage procedure. There was significant resolution of the vasospasm. The long-term clinical outcome in one patient was
excellent, the other still has minor deficits. Combined endovascular aneurysm therapy followed by intra-arterial spasmolysis
with papaverine is a technically feasable therapeutic alternative in patients with symptomatic vasospasm.
Received: 5 November 1999/Accepted: 12 July 2000 相似文献