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1.
2.
60 intracranial tumors have been studied immunohistochemically to determine the proliferation rate by staining for the monoclonal antibody KI-67, which recognizes a nuclear antigen expressed by cells in proliferation. In gliomas a clear correlation of stained nuclei to the histologically determined degree of malignancy was found: slow growing astrocytomas and oligodendrogliomas had an average proliferation rate of 1%, more malignant forms of 7–10%. Glioblastomas were found to have a growth fraction of 15%. Metastases had an even higher rate of 20% proliferating cells. In meningiomas the proliferation rate was mainly about 1%, but in three cases it was between 5% and 7%. Whether this is indicative for a higher risk of tumor recurrence, remains to be correlated to the clinical course. Hemangiopericytomas had a proliferation rate of 9% and 16%, respectively, the latter recurring within four months. It may be concluded from the results of this study, that investigation of intracranial tumors with KI 67 may be of prognostic value and can possibly contribute to an individualized tumor therapy. 相似文献
3.
Frank Makowiec Stefan Post Hans-Detlev Saeger Norbert Senninger Heinz Becker Michael Betzler Heinz J. Buhr Ulrich T. Hopt German Advanced Surgical Treatment Study Group 《Journal of gastrointestinal surgery》2005,9(8):1080-1087
Despite decreasing mortality rates, morbidity is still high after pancreatic head resection. Comparative data in the United
States and Europe show a relationship between hospital volume and mortality. Treatment strategies vary frequently, partially
because of the lack of evidence-based data. We performed a multi-institutional analysis in Germany evaluating current numbers,
indications, techniques, and complication rates of pancreatic head resection. Questionnaires were completed by seven high-volume
surgical departments regarding quantitative and qualitative aspects of pancreatic head resections in the period from 1999
to 2004 (five prospective and two retrospective institutional databases). A total of 1454 pancreatic head resections (944
for malignancy) were reported. Mean annual hospital volume ranged from 14 to 52 (10 to 43 in malignancy). Mortality was between
1.1% and 4.8%, morbidity was between 24% and 46%, and pancreatic leakage was between 9% and 20%. In malignant disease, all
centers perform standard lymphadenectomy and regard arterial infiltration as a contraindication for resection. However, the
rate of portal vein resection varied from 0% to 28%. No consensus is seen on the type of surgery for malignancy and chronic
pancreatitis. After resection for pancreatic cancer less than one fourth of the patients receive adjuvant therapy. The results
of our analysis in Germany confirm that pancreatic head resection can be performed with low mortality in specialized units.
Variations in indications, operative technique, and perioperative care may demonstrate the lack of evidence-based data and/or
personal and institutional experience. The low number of patients receiving adjuvant therapy after resection of pancreatic
cancer suggests that more efforts must be made to establish novel adjuvant therapies under randomized study conditions.
Presented at the Forty-Sixth Annual Meeting of The Society for Surgery of the Alimentary Tract, Chicago, Illinois, May 14–18,
2005 (oral presentation). 相似文献
4.
Samei E Buhr E Granfors P Vandenbroucke D Wang X 《Physics in medicine and biology》2005,50(15):3613-3625
The modulation transfer function (MTF) is well established as a metric to characterize the resolution performance of a digital radiographic system. Implemented by various laboratories, the edge technique is currently the most widespread approach to measure the MTF. However, there can be differences in the results attributed to differences in the analysis technique employed. The objective of this study was to determine whether comparable results can be obtained from different algorithms processing identical images representative of those of current digital radiographic systems. Five laboratories participated in a round-robin evaluation of six different algorithms including one prescribed in the International Electrotechnical Commission (IEC) 62220-1 standard. The algorithms were applied to two synthetic and 12 real edge images from different digital radiographic systems including CR, and direct- and indirect-conversion detector systems. The results were analysed in terms of variability as well as accuracy of the resulting presampled MTFs. The results indicated that differences between the individual MTFs and the mean MTF were largely below 0.02. In the case of the two simulated edge images, all algorithms yielded similar results within 0.01 of the expected true MTF. The findings indicated that all algorithms tested in this round-robin evaluation, including the IEC-prescribed algorithm, were suitable for accurate MTF determination from edge images, provided the images are not excessively noisy. The agreement of the MTF results was judged sufficient for the measurement of the MTF necessary for the determination of the DQE. 相似文献
5.
The rectus sheath hematoma is a generally rare disease, however the frequency of occurrence has increased with introduction of anticoagulant therapy. It almost always mimics the symptoms of acute abdomen. In 7 out of 14 cases, which we observed, an anticoagulant therapy was administered. During this therapy 5 rectus sheath hematomas occurred spontaneously. In the remaining 2 patients severe coughing attacks were reported additionally. The case histories of the other 7 patients included 3 patients with bronchitis, 2 patients with trauma and 2 patients without a relevant history ("spontaneous"). The correct diagnosis of rectus sheath hematoma could primarily be revealed by sonography in 8 of 14 patients, after which an appropriate therapy followed. In 6 patients a laparotomy was performed, because rectus sheath hematoma was not considered. The correct diagnosis was found intraoperatively as a surprising assessment. By inclusion of rectus sheath hematoma in the differential diagnosis of acute abdomen and the verification by sonography an emergency laparotomy because of a false diagnosis in the often severe ill patients can be avoided in favour of a minor and more appropriate procedure. 相似文献
6.
Staging biopsies of the bone marrow in lymphoma patients are among the most important indications and therefore of substantial practical importance. Occasionally it is the only organ infiltrated, and therefore a bone marrow biopsy is the prime diagnostic choice in cases of leukemic lymphomas. A synoptical diagnostic approach relying on immunophenotypic as well as on molecular biological criteria aside from histomorphology (cytomorphology), is of utmost importance for the subtyping of malignant lymphomas. This too can be done reliably on bone marrow biopsies, as comparative studies have yielded a concordance rate of more than 90% with lymphoma typing on corresponding lymph nodes. Cytology and the pattern of infiltrates, (i.e. diffuse, interstitial, nodular peritrabecular and intrasinusoidal), in combination with immunological phenotyping are the mainstays for subtyping, giving clear-cut decisions in most cases of small B-cell lymphoma, mantle zone as well as marginal cell and follicular lymphomas and hairy cell leukemia. Among the blastic variants the most important are the lymphoblastic lymphomas of either B- or T-cell type which have to be discerned from AML and the so-called blastoid mantle cell lymphomas. T-cell lymphomas are rare compared to B-cell lymphomas. Among the rarely seen T-cell neoplasias the lymphoma of large granular lymphocytes is the dominating lymphoma, which in most cases can only be diagnosed reliably by molecular biological means, followed by T-CLL, Sezary's syndrome and hepatosplenic chi delta lymphoma. 相似文献
7.
Between January 1981 and December 1988 a total of 95 patients underwent surgery for adrenal tumors. In 24 cases (25.3%) a so-called "incidentaloma" was found. While seven of these tumors showed hormonal activity, in seventeen patients the tumor was hormonal inactive. The size of the tumors ranged between 2 and 11 cm. Histologically all tumors were found to be benign neoplasms. Because of the lack of lethality and minimal morbidity we indicate surgery on incidentaloma of the adrenal gland for the following reasons: tumors with hormone activity, tumor size larger than 3 cm, suspecting malignoma or metastasis and finally in proven enlargement of small tumors. Only in adrenal tumors smaller than 3 cm we suggest a follow-up by ultrasound or computed tomography. 相似文献
8.
S. Riedl H.-J. Buhr Ch. Herfarth 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1994,379(1):38-43
27 patients with pancreatic and 8 with duodenal injuries were studied, 66% of whom had associated abdominal injuries. Peritoneal lavage was performed in 10 cases, and ultrasonography in 15. Laparotomy was considered to be indicated on the basis of the results in 9 cases of peritoneal lavage and in 12 cases of ultrasound examination, but in only 1 case and 2 cases, respectively, did the findings constitute the only reason for performing a laparotomy. Pancreatic and duodenal injuries were directly confirmed by ultrasonography and computer tomography only in a minority of cases. The morbiditiy of pancreatic and duodenal injuries was 66% and 25%, respectively, and lethality, 19% and 25%. Despite modern imaging techniques, clinical examination is of paramount importance for the decision as to whether operative therapy is indicated; delay leads to increased morbidity and lethality. 相似文献
9.
Trina A. Buhr Don B. Chaffin Bernard J. Martin 《Journal of occupational rehabilitation》1999,9(4):247-265
This study investigated the use of EMG biofeedback to simulate weakened rectus femorii and gastrocnemii muscles during the performance of a lifting task. Eight healthy women performed 15 kg free-style lifts from floor level. Three conditions were tested: unconstrained lifting, lifting with rectus femorii activity volitionally limited bilaterally through EMG biofeedback to less than 45% of maximal EMG activity, and lifting with the gastrocnemii limited to a similar level. Limiting leg muscle activity through biofeedback led to an alteration of lifting strategy, with resulting performance variables (joint angles and torques, angular velocities, center of pressure excursion, and segment coordination) comparing favorably with those from lifting trials performed by six women with moderate leg muscle weaknesses. The data indicate that EMG biofeedback can be used to simulate the effects of leg muscle weakness during these lifts, providing a new tool to study the biomechanics of muscle weakness. 相似文献
10.
H. J. Buhr H. Kramer J. Matthes und H. Krebs 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1980,352(1):611
Zusammenfassung Kirschner wurde 1879 in Breslau geboren. 1916 erhielt er den Ruf auf den Lehrstuhl in Königsberg, 1927 nach TÜbingen und 1934 nach Heidelberg. An diesen Stätten erbaute er neue Kliniken. Erfolgreich arbeitete er auf allen chirurgischen Teilgebieten. Besonders erwähnenswert seien die erste erfolgreiche pulmonale Embolektomie, die einzeitige Lungenlappenresektion, ein neues Verfahren in der Oesophaguschirurgie, die EinfÜhrung des halbstarren Kirschner-Drahtes, in der Schmerzbekämpfung die Avertinnarkose, die Spinalanaesthesie und die Elektrocoagulation des Ganglion Gasseri. 1932 begrÜndete er die heute von Zenker fortgefÜhrte Operationslehre. 相似文献