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991.
Dwight Dickinson Virginia N Iannone Christopher M Wilk James M Gold 《Neuropsychopharmacology》2004,55(8):826-833
BACKGROUND: It is controversial whether the cognitive deficit in schizophrenia is better characterized as generalized or as reflecting relatively independent deficits in different cognitive domains. The issue has implications for assessment practice, intervention design, and the exploration of schizophrenia genetics. METHODS: We used a specialized structural equation modeling approach, single common factor analysis, to explore the relative importance of generalized versus independent cognitive deficits in schizophrenia. Eighteen subtest scores from the Wechsler Adult Intelligence Scale-III and the Wechsler Memory Scale-III were included in the analysis. We analyzed these data for 97 schizophrenia or schizoaffective disorder outpatients and 87 healthy control subjects. RESULTS: Approximately two thirds of the overall effect of a schizophrenia diagnosis on cognitive performance was mediated through a single common factor. The Wechsler subtest scores showed almost uniformly strong relationships with this factor. The independent associations of group status with the subtest scores were smaller in magnitude and only selectively significant. CONCLUSIONS: The relatively greater magnitude of illness effects mediated through the common factor in this analysis, compared with the specific, independent effects, suggests that a generalized cognitive deficit is a core feature of schizophrenia. 相似文献
992.
K. K. Würzler M. Heisterkamp H. Böhm N. R. Kübler W. Sebald und J. F. Reuther 《Mund-, Kiefer- und Gesichtschirurgie》2004,8(2):75-82
ZusammenfassungFragestellung In der vorliegenden Studie am Göttinger Minischwein wurde die direkte Rekonstruktion des Unterkiefers nach ausgedehnter Kontinuitätsresektion mit autologem Knochen und einem osteoinduktiven Implantat untersucht.Methode An neun ausgewachsenen Göttinger Minischweinen wurde ein einseitiger, 5 cm langer Unterkieferkontinuitätsdefekt gesetzt. Die Rekonstruktion erfolgte bei vier Tieren mit einem 50×25×15 mm3 großen, kollagenen Träger, dotiert mit rhBMP-2 (400 µg/cm3). Bei zwei Tieren wurde nur der Träger alleine implantiert und bei drei Tieren das lokal resezierte Knochensegment replantiert. Die Knochenregeneration und Konsolidierung der Defekte wurde radiologisch und histologisch analysiert.Ergebnisse Nach Rekonstruktion mit dem osteoinduktiven Implantat zeigte sich bei allen Versuchstieren eine komplette knöcherne Konsolidierung des gesetzten Unterkieferkontinuitätsdefekts. Der gesamte Defekt wurde von einem biomechanisch hochwertigen, sich funktionell anpassenden Knochen überbrückt. Nach Replantation des ortsständigen autologen Knochens wird dieser nicht schnell genug knöchern integriert. In der Peripherie bilden sich nur unvollständige Knochenbrücken aus; dies führt zum vollständigen Versagen der Rekonstruktion. Ebenso findet bei der Implantation des Trägers alleine keine Konsolidierung statt.Schlussfolgerung Die direkte Rekonstruktion eines ausgedehnten, biomechanisch belasteten Defekts mit einem osteoinduktiven Implantat erwies sich als die überlegene Methode. Das hierbei entstehende knöcherne Regenerat erfährt eine unmittelbare funktionelle Strukturierung. Die Notwendigkeit zu extensiven adaptiven Umbauvorgängen wird hierdurch minimiert. 相似文献
993.
994.
Genetic predisposition for adult lactose intolerance and relation to diet, bone density, and bone fractures. 总被引:8,自引:0,他引:8
Barbara M Obermayer-Pietsch Christine M Bonelli Daniela E Walter Regina J Kuhn Astrid Fahrleitner-Pammer Andrea Berghold Walter Goessler Vinzenz Stepan Harald Dobnig Georg Leb Wilfried Renner 《Journal of bone and mineral research》2004,19(1):42-47
Evidence that genetic disposition for adult lactose intolerance significantly affects calcium intake, bone density, and fractures in postmenopausal women is presented. PCR-based genotyping of lactase gene polymorphisms may complement diagnostic procedures to identify persons at risk for both lactose malabsorption and osteoporosis. INTRODUCTION: Lactase deficiency is a common autosomal recessive condition resulting in decreased intestinal lactose degradation. A -13910 T/C dimorphism (LCT) near the lactase phlorizin hydrolase gene, reported to be strongly associated with adult lactase nonpersistence, may have an impact on calcium supply, bone density, and osteoporotic fractures in the elderly. MATERIALS AND METHODS: We determined LCT genotypes TT, TC, and CC in 258 postmenopausal women using a polymerase chain reaction-based assay. Genotypes were related to milk intolerance, nutritional calcium intake, intestinal calcium absorption, bone mineral density (BMD), and nonvertebral fractures. RESULTS: Twenty-four percent of all women were found to have CC genotypes and genetic lactase deficiency. Age-adjusted BMD at the hip in CC genotypes and at the spine in CC and TC genotypes was reduced by -7% to -11% depending on the site measured (p = 0.04). LCT(T/C-13910) polymorphisms alone accounted for 2-4% of BMD in a multiple regression model. Bone fracture incidence was significantly associated with CC genotypes (p = 0.001). Milk calcium intake was significantly lower (-55%, p = 0.004) and aversion to milk consumption was significantly higher (+166%, p = 0.01) in women with the CC genotype, but there were no differences in overall dietary calcium intake or in intestinal calcium absorption test values. CONCLUSION: The LCT(T/C-13910) polymorphism is associated with subjective milk intolerance, reduced milk calcium intake, and reduced BMD at the hip and the lumbar spine and may predispose to bone fractures. Genetic testing for lactase deficiency may complement indirect methods in the detection of individuals at risk for both lactose malabsorption and osteoporosis. 相似文献
995.
Frau Dr. K. Sternberg C. Selent N. Hakanßon J. Töllner T. Langer H. Seiter K.-P. Schmitz 《Der Urologe. Ausg. A》2004,43(10):1200-1208
The scope of our research is the development of polymer-based bioabsorbable stents for urologic applications and in vitro testing of tissue reactions of cultured ureteral and urethral segments induced by implanted polymer stent prototypes. For these purposes a tissue cultivation model was developed using selected techniques of tissue engineering. Essential advantages of degradable over nondegradable urethral stents are elimination of the adverse extraction of epithelialized stents and the potential for recovery of organ-specific functionality. Moreover, the biocompatibility of a degradable urethral stent could potentially reduce the risk of restenosis due to hyperplasia and could be used, even repeatedly, for the treatment of a number of subvesical obstructions. For the treatment of tumor-induced strictures, application of degradable polymer stents coated with cytostatic drugs may be possible. The mechanical effect of the drug-loaded stent as a “place holder” could be complemented by adjuvant or palliative approaches such as local chemotherapy. We have developed and tested in vitro a degradable urethral stent incorporated with the model drug methotrexate for local drug delivery (LDD) by diffusion and during stent degradation. 相似文献
996.
997.
M Kurimoto N Hayashi H Kamiyama S Nagai T Shibata T Asahi N Matsumura Y Hirashima S Endo 《Minimally invasive neurosurgery》2004,47(5):278-283
Neuronavigation has become an effective therapeutic modality and is used routinely for intra-axial tumor removal. This retrospective study was conducted to evaluate the clinical impact of neuronavigation and image-guided extensive resection for adult patients with supratentorial malignant astrocytomas. Between 1990 and 2002, 76 adult patients with pathologically confirmed malignant astrocytomas underwent craniotomy and removal of the tumors at the Toyama Medical and Pharmaceutical University Hospital. Of these 76 patients, 42 were treated using neuronavigation with conventional microneurosurgery and the other 34 were treated with conventional microneurosurgery alone. Postoperative early MRI with contrast enhancement was done, and gross total resection was defined as the complete absence of residual tumor. Survival time was analyzed with the Kaplan-Meier method. Prognostic factors were obtained from the Cox proportional hazards model. In univariate analysis, age (< 65), grade 3, preoperative KPS (>/= 80), use of neuronavigation, and gross total resection were significantly associated with longer survival. However, when the data were submitted to multivariate analysis, grade 3, preoperative KPS (>/= 80), and gross total resection were independent prognostic factors. The median survival periods of patients receiving gross total resection (vs. partial resection) and neuronavigation (vs. no neuronavigation) were 16 (vs. 9) months and 16 (vs. 10) months, respectively. The percentage of a gross total resection was significantly higher in the neuronavigation group compared to that in the no-navigation group (64.3 % vs. 38.2 %, p < 0.05). Neurological deterioration occurred in 4 of 42 (9.5 %) and in 6 of 34 (17.6 %) patients after surgery with neuronavigation and surgery without neuronavigation, respectively, although this difference was not statistically significant. Our results showed that neuronavigation increases the radicality in the resection of malignant astrocytomas and is objectively useful for improving survival time. 相似文献
998.
After a comprehensive rernew of the literature on syphilitic
aortitis, Longcope, (1) stated in 1913; ": . . . the presence of spiro:
chetes in these lesions, as might be expected, cannot by any means be
constantly demonstrated with Levaaiti stain. . . . . . . That these
organisms are ''Treponema pallidum seems almost certain thouS:h actual
proof of such by culture from the arterial lesions, a most difficult task,
or direct inoculation into animals, has not as yet been accomplished." 相似文献
999.
1000.