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71.
Time-released delivery of soluble growth factors (GFs) in engineered hydrogel tissue constructs promotes the migration and proliferation of embedded cells, which is an important factor for designing scaffolds that ultimately aim for neural tissue regeneration. We report a tissue engineering technique to print murine neural stem cells (C17.2), collagen hydrogel, and GF (vascular endothelial growth factor: VEGF)-releasing fibrin gel to construct an artificial neural tissue. We examined the morphological changes of the printed C17.2 cells embedded in the collagen and its migration toward the fibrin gel. The cells showed high viability (92.89 ± 2.32%) after printing, which was equivalent to that of manually-plated cells. C17.2 cells printed within 1 mm from the border of VEGF-releasing fibrin gel showed GF-induced changes in their morphology. The cells printed in this range also migrated toward the fibrin gel, with the total migration distance of 102.4 ± 76.1 µm over 3 days. The cells in the control samples (fibrin without the VEGF or VEGF printed directly in collagen) neither proliferated nor migrated. The results demonstrated that bio-printing of VEGF-containing fibrin gel supported sustained release of the GF in the collagen scaffold. The presented method can be gainfully used in the development of three-dimensional (3D) artificial tissue assays and neural tissue regeneration applications.  相似文献   
72.
OBJECTIVE: To investigate whether individuals with chronic fatigue syndrome (CFS) show an attentional bias towards health-threat information. METHODS: Attentional bias (AB) was assessed in individuals with CFS and healthy controls using a visual probe task which presented health-threat and neutral words and pictures for 500 ms. Self-report questionnaires were used to assess CFS symptoms, depression, anxiety, and social desirability. RESULTS: Compared to a healthy control group, the CFS group showed an enhanced AB towards heath-threat stimuli relative to neutral stimuli. The AB was not influenced by the type of stimulus (pictures vs. words). CONCLUSION: The finding of an AB towards health-threat information in individuals with CFS is supportive of models of CFS which underlie cognitive behavior therapy.  相似文献   
73.
This column describes an innovative, government-sponsored, countrywide mental health reform focusing on rehabilitation and community integration of persons with serious mental illness, which was enacted into law in Israel in 2000. The reform was part of the country's efforts to shift the locus of treatment and care from psychiatric institutions to the community. The authors review preliminary evidence of the impact of reform and offer cautionary notes regarding the future direction of its implementation. The decade after the law's enactment saw an impressive increase in rehabilitation services, a significant reduction in the number of psychiatric beds, and major changes in government budget allocations. The authors examine factors that may endanger the viability of reform and discuss lessons to be learned from the Israeli experience.  相似文献   
74.
We present a case of a lipomeningocele in a newborn. Prenatal sonography revealed dysraphia and a 3.8 x 4.3 cm, semisolid, echogenic mass that was continuous with the sacral area and bulged posteriorly under the skin. The mass was diagnosed after birth as a lipomeningocele based on the results of MRI. This diagnosis was confirmed histologically.  相似文献   
75.
76.
Home observations were done on sibling interactions in 31 families with a child having Down's syndrome and a non-handicapped sibling. The siblings with Down's syndrome initiated less prosocial and agonistic behaviour, but imitated more frequently than their non-handicapped siblings. These effects were found regardless of birth order. There were no effects of gender. Higher levels of prosocial behaviours among large interval dyads and in dyads with a second-born Down's syndrome child were primarily due to the age of the non-handicapped sibling. Results were similar to those in previous "normative" studies of sibling interactions.  相似文献   
77.
Prospective randomized trials involving the surgical and chemotherapeutic treatment of resectable colon cancer are reviewed. Emphasis is placed on those trials that have impacted the current management of primary colon cancer.  相似文献   
78.
Treatment of rectal cancer has changed dramatically over the past two decades. Radical surgery alone for resectable rectal cancer has been replaced by combined modality therapy. Interest in optimizing sphincter preservation and quality of life motivated surgeons to seek less radical surgery without compromising oncologic principles.  相似文献   
79.
Kadhim H  Tabarki B  De Prez C  Rona AM  Sébire G 《Neurology》2002,58(7):1125-1128
Proinflammatory cytokines were reported to be implicated in the pathogenesis of perinatal white matter lesions. The authors document for the first time the in situ detection of interleukin-2 and interleukin-2 receptor (IL-2R) in these human white matter lesions. These results suggest that interleukin-2, reported to be toxic to oligodendrocytes and myelin, could play a role in the molecular cascade leading to white matter damage in periventricular leukomalacia.  相似文献   
80.
PURPOSE: Phytochemicals in plants may have cancer preventive benefits through antioxidation and via gene-nutrient interactions. We sought to determine the effects of pomegranate juice (a major source of antioxidants) consumption on prostate-specific antigen (PSA) progression in men with a rising PSA following primary therapy. EXPERIMENTAL DESIGN: A phase II, Simon two-stage clinical trial for men with rising PSA after surgery or radiotherapy was conducted. Eligible patients had a detectable PSA > 0.2 and < 5 ng/mL and Gleason score < or = 7. Patients were treated with 8 ounces of pomegranate juice daily (Wonderful variety, 570 mg total polyphenol gallic acid equivalents) until disease progression. Clinical end points included safety and effect on serum PSA, serum-induced proliferation and apoptosis of LNCaP cells, serum lipid peroxidation, and serum nitric oxide levels. RESULTS: The study was fully accrued after efficacy criteria were met. There were no serious adverse events reported and the treatment was well tolerated. Mean PSA doubling time significantly increased with treatment from a mean of 15 months at baseline to 54 months posttreatment (P < 0.001). In vitro assays comparing pretreatment and posttreatment patient serum on the growth of LNCaP showed a 12% decrease in cell proliferation and a 17% increase in apoptosis (P = 0.0048 and 0.0004, respectively), a 23% increase in serum nitric oxide (P = 0.0085), and significant (P < 0.02) reductions in oxidative state and sensitivity to oxidation of serum lipids after versus before pomegranate juice consumption. CONCLUSIONS: We report the first clinical trial of pomegranate juice in patients with prostate cancer. The statistically significant prolongation of PSA doubling time, coupled with corresponding laboratory effects on prostate cancer in vitro cell proliferation and apoptosis as well as oxidative stress, warrant further testing in a placebo-controlled study.  相似文献   
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