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991.
    
Ohne Zusammenfassung Correspondence to Manfred Stosberg  相似文献   
992.
Early diagnosis of Parkinson's disease (PD) in nonsymptomatic patients is a key issue. An increased echogenicity of the substantia nigra (SN) was found previously in Parkinsonian patients and in a low percentage of healthy adults. These nonsymptomatic subjects also showed a reduced 18F-dopa uptake in striatum, suggesting a preclinical injury of the nigrostriatal system that could later proceed into PD. To investigate the ability of ultrasonography to detect markers of SN degeneration, such as iron deposition and neuromelanin depletion, we scanned postmortem brains from normal subjects at different ages by ultrasound and measured the echogenic area of the SN. The SN was then dissected and used for histological examinations and determination of iron, ferritin, and neuromelanin content. A significant positive correlation was found between the echogenic area of the SN and the concentration of iron, H- and L-ferritins. Multivariate analysis carried out considering the iron content showed a significant negative correlation between echogenicity and neuromelanin content of the SN. In PD, a typical loss of neuromelanin and increase of iron is observed in this brain area. The finding of a positive correlation between iron and ferritin levels and a negative correlation of neuromelanin content with the area of echogenicity at the SN could therefore provide an interesting basis for diagnosis and therapeutic follow-up studies in PD.  相似文献   
993.
Zusammenfassung Frakturen des Schenkelhalses und der pertrochantären Region werden insbesondere bei älteren Patienten häufig mit der dynamischen Hüftschraube (DHS) versorgt. Wir berichten über die Behandlung und den Verlauf bei einem 45jährigen Patienten mit beidseitiger pertrochantärer Spontanfraktur aufgrund einer hepatischen Osteopathie.  相似文献   
994.
BACKGROUND: Radioiodine uptake (RIU) is one of the main prognostic factors for curative results of radioiodine therapy in patients with differentiated thyroid cancer. Some days after application of (131)I, the uptake of a subsequent administration of radioiodine was found to be reduced. In contrast, early after irradiation with high-energy photons glucose and amino acid uptake were observed to be increased. Effects of external irradiation on RIU of thyrocytes using high-energy photons have not been investigated so far. MATERIAL AND METHODS: Two different cell lines (FRTL-5 and ML-1 cells) derived from thyroid tissue were studied in vitro. Cell lines were either incubated with (131)I only (controls) or additionally irradiated with single doses of 6 or 10 Gy of high-energy photons using a linear accelerator. Cell number and RIU were determined 24-96 h after (131)I application. RIU measurements were repeated after application of sodium perchlorate in excess to investigate specificity of the uptake. Statistical analyses were performed using non-parametric tests. RESULTS: Incubation with radioiodine as well as irradiation with high-energy photons slowed down proliferation in investigated cell lines significantly. Irradiation with solely (131)I resulted in stable or slightly decreased iodide uptake. Compared to those cells, the RIU increased significantly in externally irradiated cells, i. e., additional irradiation with 10 Gy resulted in an almost threefold increase of RIU in FRTL-5 after 72 h. The increase of RIU after irradiation was dose-dependent in both cell lines and could be blocked by perchlorate excess. CONCLUSION: It could be demonstrated that external irradiation increases RIU in thyroid cell cultures early after irradiation. The increase was dose-dependent and specific, as it could be blocked by perchlorate. This effect appears to be similar to the increase of other actively transported substances after irradiation with high-energy photons. Therefore, the results of this study may contribute to the knowledge of a generalized irradiation-induced mechanism which causes the activation of different cellular transporters. The clinical impact of these findings on combined therapy concepts has to be investigated in further experiments.  相似文献   
995.
BACKGROUND: In depressed patients, alterations in the hypothalamo-pituitary-adrenocortical (HPA) system are the most consistent neurobiological finding. HPA axis activity and cytokines are intrinsically intertwined: inflammatory cytokines stimulate adrenocorticotropic hormone (ACTH) and cortisol secretion, while, in turn, glucocorticoids suppress the synthesis of proinflammatory cytokines. METHODS: We examined alterations in plasma levels of tumor necrosis factor-alpha (TNF-alpha), levels of its soluble receptors p55 (sTNF-R p55) and p75 (sTNF-R p75) as well as changes in the HPA system function using the combined dexamethasone/corticotropin-releasing hormone (dex/CRH) test on admission and at discharge in 70 depressed inpatients without inflammation. RESULTS: On admission, TNF-alpha levels were inversely associated with the ACTH response to the combined dex/CRH test. Changes in TNF-alpha, sTNF-R p55, and sTNF-R p75 plasma levels from admission to discharge were positively correlated with the dex/CRH test outcome at discharge. Subgroup analysis revealed that this association was restricted to those patients achieving remission. In this subgroup, TNF-alpha levels at discharge were also positively correlated with dex/CRH test response at discharge. CONCLUSIONS: Our results suggest that elevated HPA axis activity in acute depression suppresses TNF-alpha system activity, while after remission, when HPA axis activity has normalized, the TNF-alpha system seems to gain influence on the HPA system.  相似文献   
996.
997.
PURPOSE: To compare the efficacy of pegylated liposomal doxorubicin (PLD) with that of a common salvage regimen (comparator) in patients with taxane-refractory advanced breast cancer. PATIENTS AND METHODS: Following failure of a first- or second-line taxane-containing regimen for metastatic disease, 301 women were randomly assigned to receive PLD (50 mg/m(2) every 28 days); or comparator-vinorelbine (30 mg/m(2) weekly) or mitomycin C (10 mg/m(2) day 1 and every 28 days) plus vinblastine (5 mg/m(2) day 1, day 14, day 28, and day 42) every 6 to 8 weeks. Patients were stratified before random assignment based on number of previous chemotherapy regimens for metastatic disease and presence of bone metastases only. RESULTS: Progression-free survival (PFS) and overall survival (OS) were similar for PLD and comparator (PFS: hazard ratio [HR], 1.26; 95% CI, 0.98 to 1.62; P =.11; median, 2.9 months [PLD] and 2.5 months [comparator]; OS: HR, 1.05; 95% CI, 0.82 to 1.33; P =.71; median, 11.0 months [PLD] and 9.0 months [comparator]). In anthracycline-na?ve patients, PFS was somewhat longer with PLD, relative to the comparator (n = 44; median PFS, 5.8 v 2.1 months; HR, 2.40; 95% CI, 1.16 to 4.95; P =.01). Most frequently reported adverse events were nausea (23% to 31%), vomiting (17% to 20%), and fatigue (9% to 20%) and were similar among treatment groups. PLD-treated patients experienced more palmar-plantar erythrodysesthesia (37%; 18% grade 3, 1 patient grade 4) and stomatitis (22%; 5% grades 3/4). Neuropathy (11%), constipation (16%), and neutropenia (14%) were more common with vinorelbine. Alopecia was low in both the PLD and vinorelbine groups (3% and 5%). CONCLUSION: PLD has efficacy comparable to that of common salvage regimens in patients with taxane-refractory metastatic breast cancer, thereby representing a useful therapeutic option.  相似文献   
998.
999.
In a two-wave community study in Munich, Germany, a representative sample of 402 people older than 85 years was restudied 1 year later. In the first cross section a total of 358 (89.1%) subjects were interviewed. One year later 263 (73.5%) subjects were reexamined. Several diagnostic systems were used. The probands showed a high prevalence of depression — nearly one quarter of the interviewees. In this extreme age group gender differences in depression were minimal. Depressives were distinctly impaired in daily life. Depressive probands were more often found in institutions than in private households. Depressives were high users of the medical care system, but very rarely treated by specialists. Need for care and certain specific especially threatening life events were identified as risk factors for depression.  相似文献   
1000.
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