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71.
Antiangiogenic drugs have been used successfully for the treatment of colorectal cancer (CRC). Viable tumor endothelial cells (TEC) and normal endothelial cells (NEC) of uninvolved colon tissue of the same patient have not been available to optimize treatment strategies in vitro. Therefore, our target was to establish a protocol for the isolation of TEC and NEC. These cells were isolated with very high purity via magnetic cell sorting of tissue samples obtained from CRC and healthy colon of eight patients. TEC and NEC expressed CD31, CD105, VE-cadherin, VCAM-1, ICAM-1 and E-selectin, formed capillaries in basal membrane extract and were able to take up acetylated low-density lipoprotein. They were negative for podoplanin, CD45, CD68 and cytokeratin-20 indicating blood vessel endothelial lineage. Intense staining of von Willebrand factor (vWF) was observed in five of eight NEC cultures, whereas vWF was absent or only slightly expressed in all TEC cultures in vitro. Low intracellular concentration of vWF was also detected in TEC and NEC at the tissue level. This demonstrated that differences exhibited by TEC and NEC in vivo are stably perpetuated in culture. The isolated cultures may provide a useful in vitro model to elucidate epigenetic effects on angiogenesis in cancer and to optimize antiangiogenic therapy.  相似文献   
72.
73.
Rapid anti-suicidal and antidepressant effects of ketamine have repeatedly been confirmed in unipolar and bipolar depression. Although meaningful antidepressant efficacy of ketamine has also been shown in depressed patients with a history of psychotic symptoms, its administration in psychotic disorders has largely been neglected due to its potential to exacerbate dissociative or psychotic symptoms. Presenting a case of a young female inpatient suffering from schizophrenia with a severe post-psychotic depression, we demonstrate a robust anti-suicidal and antidepressant effect of S-ketamine infusions administered thrice weekly for 3 weeks in total. Importantly, no relevant psychotic or dissociative symptoms occurred during the whole augmentation treatment period leading to a sustained remission of depressive symptoms and suicidality. Our safe and effective experience with intravenous S-ketamine might encourage researchers and clinicians to widen its administration range beyond the diagnosis of depression to enrich the current knowledge of ketamine effects in psychotic disorders.  相似文献   
74.
Purpose

Psychosomatic symptoms and mental health problems are highly prevalent in multimorbid elderly people challenging general practitioners to differentiate between normal stress and psychopathological conditions. The 4DSQ is a Dutch questionnaire developed to detect anxiety, depression, somatization, and distress in primary care. This study aims to analyze measurement equivalence between a German version and the original Dutch instrument.

Methods

A Dutch and a German sample of multimorbid elderly people, matched by gender and age, were analyzed. Equivalence of scale structures was assessed by confirmatory factor analysis (CFA). To evaluate measurement equivalence across languages, differential item functioning (DIF) was analyzed using Mantel–Haenszel method and hybrid ordinal logistic regression analysis. Differential test functioning (DTF) was assessed using Rasch analysis.

Results

A total of 185 German and 185 Dutch participants completed the questionnaire. The CFA confirmed one-factor models for all scales of both 4DSQ versions. Nine items in three scales were flagged with DIF. The anxiety scale showed to be free of DIF. DTF analysis revealed negligible scale impact of DIF.

Conclusions

The German 4DSQ demonstrated measurement equivalence to the original Dutch instrument. Hence, it can be considered a valid questionnaire for the screening for mental health problems in primary care.

  相似文献   
75.
PURPOSE: This study aimed to evaluate the clinical success of a hydrophilic polyvinyl siloxane impression material for fixed dental restorations under various clinical conditions. MATERIALS AND METHODS: A total of 1,466 preparations for fixed restorations in maxillary and mandibular anterior and posterior teeth were evaluated. The study contained inlay, onlay, crown, veneer, post, and adhesive-wing preparations and implants for gold, porcelain-fused-to-metal, and ceramic restorations. The preparation finish line relative to the crest of the marginal gingiva, type of restoration, and position of the teeth were recorded. Three categories were established to rate impression quality: perfect impressions, with an absence of any voids or bubbles and perfect reproduction of the preparation finish line, were rated Criteria I; acceptable impressions, with minimal defects (< or = 2 mm) not involving the preparation finish line, were rated Criteria II; and unacceptable impressions, with larger voids or bubbles (> 2 mm) or defects involving the preparation finish line, were rated Criteria III. RESULTS: Overall, 96.86% of the final impressions were clinically acceptable, 89.43% of which were rated Criteria I and 7.43% of which were rated Criteria II. Only 3.14% of the impressions were unacceptable and rated Criteria III. A significant influence on impression quality was found when the preparation finish line was more than 2 mm subgingival (P < .004), as well as when a beveled preparation was used (P < .004). The position of the teeth (P > .404) had no significant effect. CONCLUSION: Surface-activated polyvinyl siloxane impression material offers high predictability to avoid bubbles and voids in the final impression.  相似文献   
76.
Graefe's Archive for Clinical and Experimental Ophthalmology - Persisting macular holes (PMH) after surgical release of any epiretinal traction of the vitreous and adjacent membrane may rely on...  相似文献   
77.
Five samples were collected from four suspected outbreaks of African swine fever in Namibia in 2018. Sequencing of the C‐terminus of the B646L gene (p72 protein), the central hypervariable region (CVR) of the B602L gene, the E183L gene (p54 protein) and the CD2v (used to determine the serogroup) was performed on DNA isolated from the samples. Phylogenetic analyses of the B646L (p72) revealed that one of the samples belonged to genotype I while the remaining samples could not be assigned to any currently known genotype. In contrast, by using the E183L gene three of the samples were shown to belong to genotype Id and only two were of unknown genotype. Based on the analysis of the partial CD2v amino acid sequences of four of the samples, one of the viruses clustered with serogroup 2 while the other three did not cluster within any of the eight known serogroups. Examination of the CVR identified three variants with 8, 18 and 24 tetrameric tandem repeat sequences. This study indicates that at least three different genetically distinct ASFV are currently present in Namibia.  相似文献   
78.
The aim of this study was to assess T2 values of the lumbar intervertebral discs in the axial and sagittal plane views and assess their respective interobserver reliability. The lumbar intervertebral discs of 23 symptomatic patients (11 female; 12 male; mean age, 44.1 ± 10.6; range, 24-64 years) were examined at 3T. Region-of-interest (ROI) analysis was performed on axial and sagittal T2 maps by two independent observers. Intraclass correlation coefficient (ICC) was assessed for every ROI. The interobserver agreement was excellent for the nucleus pulposus (NP) in the sagittal (0.951; 95% confidence interval [CI], 0.926-0.968) and axial (0.921; 95% CI, 0.845-0.955) planes. The posterior 20% region showed a higher ICC in the axial vs the sagittal assessment (0.845; 95% CI, 0.704-0.911 vs 0.819; 95% CI, 0.744-0.873). The same was true for the posterior 10%, with the axial ROI showing a higher ICC (0.923; 95% CI, 0.865-0.953 vs 0.628; 95% CI, 0.495-0.732). The intraobserver agreement was excellent for every ROI except the sagittal 10% region, which showed good performance (0.869; 95% CI, 0.813-0.909). The sagittal nucleus pulposus was the best-performing ROI with regard to intra- and interobserver agreement in the T2 assessment of the lumbar intervertebral disc. However, the axial NP showed more stable agreements overall and across the value range. In addition, the annular analysis showed better inter- and intraobserver agreement in the axial plane view. Clinical significance: Based on the presented analysis, we highly recommend that further studies use axial T2 mapping due to the higher intra- and interreader agreement.  相似文献   
79.
Spatially varying distortions (SVDs) are common artifacts of spectacles like progressive additional lenses (PALs). To habituate to distortions of PALs, the visual system has to adapt to distortion-induced image alterations, termed skew adaptation. But how this visual adjustment is achieved is largely unknown. This study examines the properties of visual adaptation to distortions of PALs in natural scenes. The visual adaptation in response to altered form and motion features of the natural stimuli were probed in two different psychophysical experiments. Observers were exposed to distortions in natural images, and form and motion aftereffects were tested subsequently in a constant stimuli procedure where subjects were asked to judge the skew, or the motion direction of an according test stimulus.Exposure to skewed natural stimuli induced a shift in perceived undistorted form as well as motion direction, when viewing distorted dynamic natural scenes, and also after exposure to static distorted natural images. Therefore, skew adaptation occurred in form and motion for dynamic visual scenes as well as static images. Thus, specifically in the condition of static skewed images and the test feature of motion direction, cortical interactions between motion-form processing presumably contributed to the adaptation process.In a nutshell, interfeature cortical interactions constituted the adaptation process to distortion of PALs. Thus, comprehensive investigation of adaptation to distortions of PALs would benefit from taking into account content richness of the stimuli to be used, like natural images.  相似文献   
80.

Purpose

Elevated T2-values of articular cartilage are associated with an increase in cartilage water that results from a damaged collagen matrix, and provide a marker for cartilage damage. We used T2 mapping to analyse the rim of cartilage defects that appeared to be intact on the morphological sequences, to determine whether there are early biochemical changes already present.

Method

We calculated T2 values for the rim of cartilage defects in 25 patients and compared these values to another area of control cartilage in these patients.

Results

A highly significant increase in T2 values of the deep, superficial, and global layer of the rim versus the control cartilage was measured. ANOVA showed a significant correlation of the defect levels with the T2 values of the deep and global zone of the adjacent cartilage tissue, but not with the superficial zone.

Conclusion

Although cartilage appears to be intact on morphological sequences, T2 mapping can show a loss of structural anisotropy of collagen and the associated increase in cartilage water that indicates the destruction of the adjacent cartilage. Preoperative information about the degree of damage of the collagen matrix will support decision making for cartilage repair.  相似文献   
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