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991.
Teresa Santantonio Maria-Christina Jung Ralf Schneider Giuseppe Pastore Gerd R. Pape Hans Will 《Journal of hepatology》1991,13(3):368-371
Hepatitis B virus (HBV) variants with a stop codon, a mutated translation initiation codon or other mutations in the pre-C region which prevent e-antigen expression are highly prevalent in anti-HBe chronic carriers and can be positively selected from a mixed virus infection. Our laboratories recently described pre-C variants with two pre-C mutations which prevent HBeAg expression. Here we have investigated whether there is a selective pressure for acquisition of the second pre-C mutation. By direct sequencing of amplified HBV DNA from sera of a chronic carrier taken during a 6-year follow-up, we found that genomes of a virus population virtually all had a pre-C translation initiation codon mutation and about 50% had an additional stop codon mutation. With the onset of interferon treatment, the genomes with the stop codon mutation increased to more than 95% while the frequency of the translation initiation codon mutation in all genomes remained constant. These data indicate positive selection (possibly immune-mediated and HBeAg-targeted) for a second pre-C mutation. This putative enhancement of negative translational control may be present because a pre-C translation initiation codon mutation cannot totally prevent HBeAg expression and is therefore less frequent. 相似文献
992.
Functional motor asymmetries correlated with clinical findings in unmedicated schizophrenic patients
Inge Gorynia Ralf Uebelhack 《European archives of psychiatry and clinical neuroscience》1992,242(1):39-45
Motor asymmetries were investigated in 28 unmedicated schizophrenic in-patients and 32 healthy controls. Of the patients, who were assessed as right-handers by a handedness questionnaire, 46.4% changed their motor laterality in at least one part of the tapping test series, probably because of a decrease of functional hemispheric asymmetry. These patients were characterized by more pronounced psychotic symptoms than those who did not change motor laterality. According to the tapping frequency, two groups of patients could be distinguished: the high- and the low-frequency group. In both groups certain tapping data could be correlated with characteristic clinical features. While the findings in the high-frequency group point to an enhanced activation level of the right hemisphere and appear to be correlated with the onset of positive symptoms and better prognosis, the findings in the low-frequency group may be a reflection of a disturbed function of the left frontal region and seem to be correlated with a gradual chronic development of predominant negative symptoms with worse prognostic implications. 相似文献
993.
Axel Hempfing Ralf Schoeniger Peter P Koch Oliver Bischel Marc Thomsen 《Journal of orthopaedic research》2007,25(10):1389-1394
Patellofemoral complications following knee arthroplasty are a well-known problem. Patellar ischemia has been suspected to be causative for fracture, anterior knee pain, and patella component failure. The purpose of this study was to assess the influence of knee arthroplasty surgical dissection on patellar blood flow. Patellar blood flow was measured by means of intraosseous laser Doppler flowmetry (LDF) in 10 patients undergoing total knee arthroplasty by a standard medial parapatellar approach. The initial blood flow was 121.6 +/- 114.7 AU. The signal significantly decreased by 71% (p = 0.0051) when the knee was flexed and lost the pulsatile signal pattern in 80%. After arthrotomy, the signal was 100.1 +/- 120.3 AU in extension. The lowest signal was found in flexion and eversion of the patella (mean, 18 +/- 10.7 AU) and all signals lost pulsatility. As compared to the initial values, completion of the soft tissue dissection did not lead to a significant change of the blood flow signal (121.3 +/- 104.8; p = 0.6835). Flexion of the knee joint markedly reduced patellar perfusion. Standard medial parapatellar approach did not significantly change patellar blood flow. This study does not support the theory of postoperative patellar ischemia as a cause of anterior knee pain or patellofemoral problems. 相似文献
994.
Jan P. Petersen Andreas Ruecker Dietrich von Stechow Peter Adamietz Ralf Poertner Johannes M. Rueger Norbert M. Meenen 《European Journal of Trauma》2003,29(1):1-10
Background: Until today, no universally successful therapy to treat substantial articular cartilage defects has been available. Numerous therapeutic approaches can only improve clinical symptoms of joint lesions, but cannot stimulate the regenerative and reactive capacity of the biological tissue in the defect, and, thus, cannot restore an articular surface capable of functional load bearing. Some other therapeutic options promised impressing results at the beginning, but did not withstand the process of a closer investigation. Even after laborious, invasive and expensive therapies, patients still complain about pain, joint effusions, restricted movement, or articular blockage. Established and Novel Therapies: The aim of all therapeutic procedures to treat patients with damaged articular cartilage is to reconstruct the integrity of the articular cartilage surface in order to enable them to live an unrestricted painless professional and private life. This article gives an overview of the clinically established procedures, their indications and the present long-term results, as well as a crucial look on the limitations of each approach. Novel therapies, which integrate molecular biology techniques and tissue engineering into transplantation surgery, are introduced and analyzed in terms of their capability and future potential. 相似文献
995.
Bahman Dolati Renate Larndorfer Dietmar Krappinger Dr. Ralf E. Rosenberger 《Operative Orthopadie und Traumatologie》2007,19(1):16-31
OBJECTIVE: Minimally invasive stabilization of the posterior pelvic ring in type C injuries. INDICATIONS: Unstable type C injuries of the pelvic ring, uni- or bilateral. - Transsymphyseal-transsacral instability. - Transpubic-transsacral instability. - Transsymphyseal-transsacroiliac instability. - Transpubic-transsacroiliac instability. CONTRAINDICATIONS: Fractures in childhood. Comminuted fractures of the ilium. Patients with skin and soft tissues in a poor condition and/or local infection. Sacral fractures with a neurologic deficit are not a contraindication because they can be decompressed by distraction and stabilized in a neutral position by plate fixation. SURGICAL TECHNIQUE: Nut-shaped osteotomy of the posterior superior iliac spine bilaterally through two short, vertical skin incisions. Tunneling through the muscles of the back to the opposite side. Length measurement for a 4.5-mm pelvic reconstruction plate. The plate is bent by about 70 degrees over the fourth lateral hole. Slide-insertion of the plate and bending of the free plate end for close fit. Cancellous bone screws are inserted into the plate holes. Refixation of the osteotomized bone fragments over the plate with small-fragment, cancellous bone screws. RESULTS: 34 patients with an average age of 42.6 years were treated according to the described method from 1998 to 2005; 18 were polytraumatized. The anterior pelvic ring was also stabilized by surgery in 28 patients for eleven of whom it was the first intervention in a two-stage procedure. 25 patients were available for clinical and radiologic follow-up at 17 months, on average. The plain radiographs after 1 year showed a very good outcome in 16 patients (maximal displacement of the posterior pelvic ring < 5 mm) and a good outcome in eight patients (displacement of 5-10 mm). In two patients there was loss of reduction in the 1st postoperative year despite a very good reduction result immediately postoperatively (dislocation < 5 mm), whereby the dislocation for one patient was < 10 mm on the final radiograph and 19 mm for the other. One patient presented with a late infection 11 weeks postoperatively that healed after implant removal and wound debridement. In two other patients, prominent screw heads, which were used for refixation of the osteotomized posterior superior iliac spine, had to be removed under local anesthesia in the 10th postoperative week. The further course for these two patients was uneventful. In one patient the implants were retrieved in the 5th postoperative month because the patient complained of internal hot and cold sensations although the soft tissue was not irritated. The plates were removed in six other cases after the fracture/instability had healed, i. e., after 9-12 months, on average; in all other cases the implants were left in situ. 相似文献
996.
997.
Simon Hoelzer MD Werner Waechter MD Andrew Stewart Raymond Liu Ralf Schweiger PhD Joachim Dudeck MD 《Journal of evaluation in clinical practice》2001,7(4):355-363
Measures are designed to evaluate the processes and outcomes of care associated with the delivery of clinical (and non‐clinical) services. They allow for intra‐ and interorganizational comparison to be used continuously to improve patient health outcomes. The use of performance measures always means to abstract the complex reality (medical scenarios and procedures) in order to provide an understandable and comparable output. Measures can focus on global performance. The more detailed data are available the more specific judgements with respect to the appropriateness of clinical decision‐making and implementation of evidence are feasible. Externally reported measures are intended both to inform and lead to action. By providing this information, deficiencies in patient care and unnecessary variations in the care process can be uncovered. Such variations have contributed to disparities in morbidity and mortality. The developments in information technology, especially world‐wide interconnectivity, standards for electronic data exchange and facilities to store and manage large amounts of data, offer the opportunity to analyse health‐relevant information in order to make the delivery of healthcare services more transparent for consumers and providers. Global performance measures, such as the overall life expectancy (mortality) in a country, can give a rough orientation of how well health systems perform but they do not offer general solutions nor spe‐cific insights into care processes that have to be improved. In contrast to population‐based measures, case‐based performance measures use a defined group of patients depending on specific patient characteristics and features of disease. By means of these measures we are able to compare the number of patients that receive a necessary medical procedure against those patients who do not. The use of case‐based measures is a bottom‐up approach to improve the overall performance in the long run. They are not only a tool for global orientation but can offer a straightforward link to the areas of deficient care and the underlying procedures. Performance measures are relevant to providers as well as consumers, from their own individual perspective. Cased‐based measures focus on the management of individual patient. This approach to performance measurement can inform physicians in a meaningful and constructive way by monitoring their individual performance and by pointing out possible areas of improvement. 相似文献
998.
Vogl Thomas J. Mack Martin G. Straub Ralf Eichler Katrin Zangos Stephan Engelmann Kerstin Hochmuth Kathrin Ballenberger Sabine Jacobi Volkmar Diebold Thomas 《European radiology》2002,12(3):S101-S104
European Radiology - We report a case of a 52-year-old woman with a palpable recurrent metastasis of a neuroendocrine carcinoma to the upper outer quadrant of the right breast. For the treatment of... 相似文献
999.
1000.