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991.
A variety of data indicate that the cerebellum participates in perceptual tasks requiring the precise representation of temporal information. Access to the word form of a lexical item requires, among other functions, the processing of durational parameters of verbal utterances. Therefore, cerebellar dysfunctions must be expected to impair word recognition. In order to specify the topography of the assumed cerebellar speech perception mechanism, a functional magnetic resonance imaging study was performed using the German lexical items "Boden" ([bodn], Engl. "floor") and "Boten" ([botn], "messengers") as test materials. The contrast in sound structure of these two lexical items can be signaled either by the length of the wordmedial pause (closure time, CLT; an exclusively temporal measure) or by the aspiration noise of wordmedial "d" or "t" (voice onset time, VOT; an intrasegmental cue). A previous study found bilateral cerebellar disorders to compromise word recognition based on CLT whereas the encoding of VOT remained unimpaired. In the present study, two series of "Boden - Boten" utterances were resynthesized, systematically varying either in CLT or VOT. Subjects had to identify both words "Boden" and "Boten" by analysis of either the durational parameter CLT or the VOT aspiration segment. In a subtraction design, CLT categorization as compared to VOT identification (CLT - VOT) yielded a significant hemodynamic response of the right cerebellar hemisphere (neocerebellum Crus I) and the frontal lobe (anterior to Broca's area). The reversed contrast ( VOT - CLT) resulted in a single activation cluster located at the level of the supratemporal plane of the dominant hemisphere. These findings provide first evidence for a distinct contribution of the right cerebellar hemisphere to speech perception in terms of encoding of durational parameters of verbal utterances. Verbal working memory tasks, lexical response selection, and auditory imagery of word strings have been reported to elicit activation clusters of a similar location. Conceivably, representation of the temporal structure of speech sound sequences represents the common denominator of cerebellar participation in cognitive tasks acting on a phonetic code. 相似文献
992.
Subic-Wrana C Bruder S Thomas W Gaus E Merkle W Köhle K 《Psychotherapie, Psychosomatik, medizinische Psychologie》2002,52(11):454-460
Preliminary findings of an ongoing study of the distribution of alexithymia in different diagnostic-groups of psychosomatically ill in-patients (n = 240, will be increased to n = 400) are reported. Alexithymiea is measured simultaneousely by the Levels of Emotional Awareness Scale (LEAS, a performance-test) and the 20-item Toronto Alexithymia Scale (TAS 20, a self-report-scale). Measured by the LEAS and compared with other diagnostic groups (affective, anxiety and compulsive-obsessive disorders; adjustment disorders; eating disorders), patients with somatoform disorders showed a decreased ability to be aware of and to communicate their emotional states. This finding which meets theoretical considerations about the origin of alexithymia could not be found with the TAS 20. The TAS 20 did not differentiate between the diagnostic groups, but showed - in accordance with two other self-report-scales (STAI for self reported anxiety as a personality trait and SCL-90-R for self reported somatic und psychic complaints) - higher mean scores at the onset than at the end of treatment. Methodical implications of the different findings of the two alexithymia scales are discussed. 相似文献
993.
Zipfel S Reas DL Thornton C Olmsted MP Williamson DA Gerlinghoff M Herzog W Beumont PJ 《The International journal of eating disorders》2002,31(2):105-117
OBJECTIVE: Partial day hospitalization programs for the treatment of eating disorders are increasingly being developed worldwide. METHOD: First, a systematic database search of day hospitalization programs for eating disorders, published in either English or German, was conducted. Programs that provided sufficient information on their program structure were summarized and compared across various dimensions. Second, the responsible program directors were contacted to provide additional information regarding outcome data, current trends, challenges, and future directions of their programs. Third, outcome data from day programs presented at international conferences were included to expand the base of the review. DISCUSSION: Although the programs from different countries and health care environments varied in terms of their purpose and operated within very different health care systems, many similarities were found to exist, including the use of a multidisciplinary staff and reliance on group treatment as the primary means of therapy. Marked differences were noted in terms of inclusion criteria and intensity of care. 相似文献
994.
Colombo G Serra S Brunetti G Atzori G Pani M Vacca G Addolorato G Froestl W Carai MA Gessa GL 《Alcohol and alcoholism (Oxford, Oxfordshire)》2002,37(5):499-503
AIMS: The present study investigated the effect of the gamma-aminobutyric acid (GABA)(B) receptor agonists, baclofen and CGP 44532, on the acquisition of alcohol drinking behaviour in selectively bred Sardinian alcohol-preferring (sP) rats. METHODS: Baclofen [0, 1 and 3 mg/kg, intraperitoneally (i.p.)] and CGP 44532 (0, 0.1, 0.3 and 1 mg/kg, i.p.) were administered immediately before alcohol presentation to alcohol-naive sP rats. Alcohol was offered under the two-bottle free-choice regimen with unlimited access for 24 h/day. Drug treatment was repeated once daily for 10 consecutive days. RESULTS: Baclofen and CGP 44532, dose-dependently and with comparable efficacy, suppressed alcohol intake; compensatory increases in water intake left total fluid intakes virtually unchanged. CONCLUSIONS: These results demonstrate that baclofen and CGP 44532 prevent the acquisition of alcohol drinking behaviour in sP rats, and suggest the involvement of the GABA(B) receptor in the mechanisms underlying the disclosure and experience of the reinforcing properties of alcohol in this rat line. 相似文献
995.
Pet birds and risk of lung cancer in North-Western Germany 总被引:35,自引:0,他引:35
Jöckel KH Pohlabeln H Bromen K Ahrens W Jahn I 《Lung cancer (Amsterdam, Netherlands)》2002,35(1):29-34
The relationship between non-small cell lung cancer and platelet counts, serum levels of vascular endothelial growth factor (VEGF) and endostatin, is unclear. Platelet counts and serum VEGF and endostatin levels were measured preoperatively in 99 patients with non-small cell lung cancer, and the relationship between these factors and clinicopathological features, including prognosis, was examined. Mean serum VEGF level was slightly higher in patients than in healthy subjects (P=0.23). Mean serum endostatin level was 42.4+/-40.4 ng/ml in patients compared to 16.3+/-10.3 ng/ml in healthy subjects (P=0.0003). Serum endostatin levels were significantly higher in patients with involvement greater than T2 or stage IB, compared to other patients. Platelet count and serum endostatin level greater than the median were associated with poor prognosis. Our results suggested that platelet count and serum endostatin level may be useful markers for non-small cell lung cancer. 相似文献
996.
Laack E Dierlamm T Knuffmann C Popp J Schmied B Dürk H Wacker-Backerhaus G Zeller W Verpoort K Fiedler W Kurt Hossfeld D 《Lung cancer (Amsterdam, Netherlands)》2002,36(3):303-307
The aim of this pilot study was to evaluate the activity and toxicity of docetaxel plus carboplatin as second-line treatment in patients with metastatic non-small cell lung cancer (NSCLC). Patients received docetaxel 75 mg/m(2) followed by carboplatin AUC 5 on day 1 every 3 weeks in an out-patient setting. Twenty-six patients were enrolled; 23 patients were diagnosed stage IV disease and three patients had a IIIB disease with malignant pleural effusion. The median interval from first to second-line treatment was 3.5 months (range 1-13). Patients received a total of 101 cycles with a median number of four cycles per patient (range 1-6). Five patients achieved a partial remission (19.23%; 95% confidence interval (CI) 6.55-39.35%), 11 had stable disease (42.31%) and ten progressed (38.46%) after initiation of second-line therapy. Median survival was 243 days (95% CI 182-336 days), the median progression-free survival was 118 days (95% CI 89-170 days), and the 1-year survival rate was 25.98% (95% CI 6.33-45.63%). Moderate haematological and mild nonhaematological toxicities were observed. No treatment-related death occurred. In conclusion, docetaxel plus carboplatin as second-line regimen has a reasonable activity with good tolerance and encouraging survival data. 相似文献
997.
Schlott T Thasler W Gorzel C Pahernik S Brinck U Eiffert H Droese M 《Anticancer research》2002,22(3):1545-1551
BACKGROUND: Preneoplastic and neoplastic lesions of the liver are suspected to arise as a result of estrogen treatment. Here we present the first report on the modulational effects of the steroids 17beta-estradiol (E2) and 17alpha-ethinylestradiol (EE2) on oncogene MDM2 in human hepatocytes. MATERIALS AND METHODS: Collagen-embedded cultures of hepatocytes stimulated with different E2/EE2 concentrations were analyzed by immunocytochemistry, RT-PCR and sequencing for MDM2 protein/mRNA expression, MDM2 mRNA splicing and MDM2 gene mutation. RESULTS: The hepatocytes responded to stimulation with steroid E2/EE2 concentrations from 1-100 nmol/l with the overexpression of MDM2 protein while non-stimulated cells were negative. Stimulation with 1 nmol/l E2 and 10-100 nmol/l EE2 induced MDM2 splicing variants. Hepatocytes treated with 100 nmol/l E2 contained full-length MDM2 mRNA carrying a new type of MDM2 gene mutation. Unstimulated hepatocytes revealed neither mRNA splicing nor alteration of the MDM2 genes. CONCLUSION: The data show that steroid hormones are involved in the induction of MDM2 alterations in benign human hepatocytes. We speculate that some of the alterations may influence MDM2 function, thus possibly favouring genesis of liver changes. 相似文献
998.
Inhibition of angiogenesis in vitro by alphav integrin-directed antisense oligonucleotides 总被引:2,自引:0,他引:2
Kronenwett R Gräf T Nedbal W Weber M Steidl U Rohr UP Möhler T Haas R 《Cancer gene therapy》2002,9(7):587-596
The integrin alpha v beta 3 plays a central role in angiogenesis. In this study, we used antisense oligodeoxyribonucleotides (ONs) directed against the alpha v subunit of alpha v beta 3 to inhibit integrin expression. Ten ON sequences, which were selected by systematic alignment of computer-predicted secondary structures of alpha v mRNA, were transfected into human umbilical vein endothelial cells (HUVECs). Following stimulation by PMA, five antisense ONs significantly inhibited alpha v mRNA and protein expression in activated HUVEC at a concentration of 0.05 mciroM with complete prevention of PMA-induced alpha v up-regulation by the most potent antisense ON. Inhibition of alpha v expression was associated with significant inhibition of migration of HUVEC by 28% and had no effect on proliferation and apoptosis. Moreover, transfection of antisense ON inhibited the formation of tube-like structures of HUVEC in Matrigel by 44%. In a cell culture model of angiogenesis consisting of a co-culture of endothelial cells with fibroblasts, transfection of antisense ONs resulted in an inhibition of tube formation of 61%. In conclusion, alpha v antisense ONs are potent inhibitors of angiogenesis in vitro. They might, therefore, be a therapeutic alternative to antagonists, which directly bind to alpha v integrins, and might be useful for the treatment of malignant tumors and hematological malignancies. 相似文献
999.
Karanikas G Köstler WJ Becherer A Wiesner K Dudczak R Krainer M Kletter K 《Oncology reports》2002,9(5):1009-1013
The lipophilic cationic compound Tc-99m-tetrofosmin has been demonstrated to be a valuable tool for the detection of a variety of tumours. Tc-99m-tetrofosmin uptake by sarcomas in vitro as well as in primary tumours has been reported. Data on the visualisation of metastatic soft tissue sarcomas using this tracer are missing so far. Ten consecutive patients with histopathologically verified metastatic soft tissue sarcoma were included in the present study. Five patients had previously received cytotoxic treatment, the other five patients were chemonaive. All patients underwent whole body planar examination after administration of 500-550 MBq Tc-99m-tetrofosmin, and in case of lung metastases on CT scan, SPECT images were carried out. Non-physiological accumulation of the tracer was considered as a positive result. Scintigraphic results were compared to conventional imaging by means of MRI/CT scanning. Visualisation of distant metastases was achieved in five patients all of whom were chemonaive, while in the chemotherapeutically pretreated patient group (n=5) false negative results were seen. Progressive disease was confirmed by follow-up in all patients. Pulmonary metastases were visualised only in SPECT acquisition and not on planar images. In one patient with diffuse bone marrow infiltration (inflammatory myofibroblastic sarcoma) Tc-99m-tetrofosmin scintigraphy was positive, while CT showed a negative result. According to our results, detection of metastatic soft tissue sarcomas by Tc-99m-tetrofosmin scintigraphy was strongly dependent on the history of previous treatment of the patient. A positive finding before initiation of chemotherapy was not indicative for subsequent therapeutic response. In the staging of chemonaive patients with metastatic soft tissue sarcoma Tc-99m-tetrofosmin may provide some additional information. 相似文献
1000.
Steinhoff C Prior A Reichmann G Seifert HH Schulz WA 《International journal of oncology》2002,21(5):1033-1040
Inactivation of P53 and RB functions are crucial changes in bladder cancer (TCC). High-level re-expression of P53 elicits apoptosis in TCC cell lines, but also--as shown here--in normal uroepithelial cells. Compromised RB function is thought to cause increased activity of E2F-dependent promoters in carcinoma cells. Indeed, several, but not all E2F-dependent promoters were stronger in TCC lines than in normal cells, with the highest activities in cell lines lacking RB rather than p16INK4A. Re-expression of p53 from an E2F-dependent promoter suppressed clone formation and induced apoptosis in TCC lines as efficiently as expression from the stronger RSV-LTR or LINE-1 promoters. In normal cells, p53 expression from an E2F-dependent promoter was tolerated, whereas expression from both stronger promoters was lethal. Thus, specific E2F-dependent promoters allow adjustment of p53 expression to selectively induce apoptosis in TCC vs. normal uroepithelial cells. This approach could be useful in targeting apoptosis to TCC and other carcinomas lacking p53 and RB function. 相似文献