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101.
To better understand how medication status and task demands affect cognition in major depressive disorder (MDD), we evaluated medication-naïve patients with MDD, medicated patients with MDD receiving the selective serotonin reuptake inhibitors (SSRI) paroxetine, and healthy controls. All three groups were administered a computer-based cognitive task with two phases, an initial phase in which a sequence is learned through reward-based feedback (which our prior studies suggest is striatal-dependent), followed by a generalization phase that involves a change in the context where learned rules are to be applied (which our prior studies suggest is hippocampal-region dependent). Medication-naïve MDD patients were slow to learn the initial sequence but were normal on subsequent generalization of that learning. In contrast, medicated patients learned the initial sequence normally, but were impaired at the generalization phase. We argue that these data suggest (i) an MDD-related impairment in striatal-dependent sequence learning which can be remediated by SSRIs and (ii) an SSRI-induced impairment in hippocampal-dependent generalization of past learning to novel contexts, not otherwise seen in the medication-naïve MDD group. Thus, SSRIs might have a beneficial effect on striatal function required for sequence learning, but a detrimental effect on the hippocampus and other medial temporal lobe structures is critical for generalization.  相似文献   
102.
Donor site morbidity following radial forearm flap (RFF) harvest remains a controversial issue. The aim of this meta-analysis was to answer the question “Are the range of wrist movements (range of motion, ROM) and hand strength affected after RFF harvesting?” The PubMed, Embase, Scopus, and Cochrane Library electronic databases were systematically searched (to December 2019). Self-controlled studies evaluating hand biomechanics after RFF harvest were included. Weighted mean differences with 95% confidence intervals were calculated using the random-effects model. The outcome variables were ROM, forearm movements, grip, and pinch strengths. Thirteen studies involving a total of 335 patients were included. With the exception of grip strength and supination, which showed statistically significant reductions of about 2.40 kg and 2.86° (P < 0.05), all other ROM, forearm movements, and pinch strengths showed an insignificant difference when the operated hand was compared to the non-operated hand (P > 0.05). Regression analysis showed that the method of donor site closure and size of the donor site defect had an insignificant impact on hand biomechanics. This study confirms the lack of discernible biomechanical morbidity after RFF transfer. The minimal reduction in hand biomechanics after RFF is considered to be clinically negligible.  相似文献   
103.
104.
CardioVascular and Interventional Radiology - To describe our institutional experience with MVP™ micro vascular plug systems for the treatment of pulmonary arteriovenous malformations...  相似文献   
105.
Introduction: Ghrelin is an orexigenic hormone which favors food-seeking behavior and has been postulated to be a biomarker of stress. We conducted a systematic review and meta-analysis on the evolution of ghrelin levels following acute stress. Methods: The PubMed, Cochrane Library, Embase, and ScienceDirect databases were searched for studies reporting ghrelin levels before and after acute stress in humans. Results: We included ten studies for a total of 348 patients. Acute stress (intervention) was always in a laboratory. Acute stress was psychological (Trier Social Stress Test), physical, or mixed (cold pressure test). The overall meta-analysis demonstrated an increase in ghrelin after the stress intervention (ES = 0.21, 95CI 0.09 to 0.34) compared with baseline levels. Stratification by time demonstrated an acute increase in ghrelin levels in the five minutes immediately following the initiation of stress (0.29, 0.10 to 0.48) but without any difference after. Obese individuals had a more significant (ES = 0.51, 95CI 0.18 to 0.84) and prolonged increase in ghrelin levels for up to 45 min compared with non-obese individuals who had a significant increase only five minutes after stress. Moreover, the ghrelin levels increased in response to stress with BMI (coefficient 0.028, 0.01 to 0.49; p = 0.013) and decreased with the time after the stress intervention (coefficient -0.007, −0.014 to −0.001; p = 0.025). Conclusion: Ghrelin is a biomarker of stress, with a short-term increase following acute stress. Obese individuals have both a higher and prolonged response, emphasizing the link between obesity and stress.  相似文献   
106.

Introduction

Endothelial-cell-specific molecule-1 or endocan is a proteoglycan with tumorigenic activity through both its glycan and protein cores. Endocan mRNA is identified as one of the most significant molecular signatures defining a poor prognosis in lung, breast, kidney, and hepatocellular cancer.

Objective

To assess the clinical value of endocan expression in ovarian cancer tissues in association with other prognostic factors and its impact on overall survival.

Setting

Oncology unit of Zagazig University Hospitals, Egypt.

Study design

Prospective observational cohort.

Patients and methods

One hundred primary ovarian cancer patients were recruited as study group, another 100 patients undergoing hysterectomy and oophorectomy due to uterine fibroid were the control group. Angiogenesis was determined by immunohistochemical staining, using anti-endocan, and anti vascular endothelial growth factor (VEGF) monoclonal antibodies.

Results

Endocan was expressed in endothelium of ovarian cancer tissue specimens in all patients with no expression in endothelium of normal ovarian tissue in the control group. VEGF was also expressed in endothelium of all specimens of ovarian cancer tissue, compared with 70 % expression in normal ovarian tissue specimens in the control group. A significant association was found between endocan-microvessel density (MVD) and tumor histology, tumor size, staging, and grading. No significant association was found between VEGF expression and any of the clinicopathological variables. Overall survival of patients was inversely associated with endocan-MVD (P < 0.01). Multivariate analysis showed that endocan-MVD was an independent prognostic marker for overall survival of epithelial ovarian cancer (P < 0.01).

Conclusion

Endocan could be a reliable marker to predict the survival in epithelial ovarian cancer patients.  相似文献   
107.
Purpose: The aim of this study was to compare between the effects of resilient liner and clip attachments of bar‐implant‐retained mandibular overdenture on peri‐implant tissues. Materials and methods: In a randomized‐controlled clinical trial, 30 edentulous male patients (mean age 62.5 years) were equally assigned to two groups. In each patient, two implants were inserted in the canine area of the mandible using a two‐stage surgical protocol. After 3 months, the implants were connected with resilient bars. Mandibular overdentures were retained to the bars with either clips (group I) or silicone‐resilient liners (group II). Peri‐implant tissues were evaluated clinically (with regard to plaque scores, gingival scores and probing depths) and radiographically (with regard to peri‐implant vertical and horizontal alveolar bone changes). Evaluations were performed at the time of overdenture insertion (T0), 6 months (T6) and 12 months (T12) after overdenture insertion. Results: After 12 months of using bar‐implant‐retained mandibular overdenture, the resilient liner attachment had significantly decreased peri‐implant plaque score, gingival score, probing depth, vertical and horizontal bone loss when compared with the clip attachment. Conclusion: Within the limitations of this study, and in terms of peri‐implant tissue health of bar‐implant‐retained mandibular overdenture, we recommend resilient liner rather than clip attachment. To cite this article:
Elsyad MA, EL Shoukouki AH. Resilient liner vs. clip attachment effect on peri‐implant tissues of bar‐implant‐retained mandibular overdenture: a 1‐year clinical and radiographical study.
Clin. Oral Impl. Res. 21 , 2010; 473–480
doi: 10.1111/j.1600‐0501.2009.01879.x  相似文献   
108.
109.
Purpose : The dense nonretentive surface of zirconia implants was modified into a nanoporous surface using selective infiltration etching surface treatment. The aim of this study was to investigate the influence of such a nanoporous modified zirconia surface on the attachment of human osteoblasts. Materials and Methods : Human osteoblasts were cultured for 21 days on (i) selective infiltration etched zirconia (nanoporous surface), (ii) polished zirconia, (iii) polished titanium, or (iv) airborne particle abraded acid etched (SLA) titanium disks. After the culture period the following parameters were assessed: number of cells, the morphology of the cells, the attachment of the cells, alkaline phosphatase activity, and the level of total protein (α= 0.05). Results : Statistical analysis revealed a significantly higher cell count on the third (F = 17.4, p < 0.001) and eighth day (F = 163, p < 0.001) for nanoporous zirconia and SLA titanium surfaces compared to polished specimens. The number of cells (nanoporous zirconia 160 ± 20/mm2, SLA titanium 133 ± 15/mm2) and cell size (nanoporous zirconia 50.7 ± 3 μm, SLA titanium 42.5 ± 4 μm) were significantly higher than polished specimens. Nanoporous zirconia specimens demonstrated comparable alkaline phosphatase activity (0.0036 ± 0.0035 ng/μl) and intracellular protein content (72.7 ± 0.9 ng/μl) compared to other tested groups. Scanning electron microscopy revealed that cells attached on the polished surface using finger‐like processes, whereas on the nanoporous surface, finger‐like processes were not observed, as the cell membrane appeared to be in close proximity to the underlying surface. Conclusion : The findings of this study suggest that a nanoporous zirconia surface favors cell growth and attachment compared to a polished surface. It was proposed that a nanoporous zirconia surface may improve clinical performance of zirconia implants.  相似文献   
110.
We evaluated changes in serum zinc (Zn) and copper (Cu) levels in two groups of children with chronic renal failure (CRF) – children with CRF who were on regular hemodialysis (Group 1, n=40) and children with CRF who were on conservative management (Group 2, n=31) – and in one group of healthy children (Group 3, n=30). All of the participants in the study were between 5–18 years old, and the composition of the three groups was almost identical with respect to age and sex. The length of time the children in Group 1 had been on hemodialysis varied between 3 and 52 months (mean: 20.97±14.8 months). To evaluate the impact of the duration of dialysis on serum levels of Zn, we further sub-divided Group 1 patients into two subgroups: Subgroup A patients (n=20) had been on hemodialysis therapy for less than 18 months (mean: 8.85±4.83 months); Subgroup B patients (n=20) had been on hemodialysis therapy for longer than 18 months (mean: 33.1±10.86 months). The PIXE (proton-induced X-ray emission) was used for measuring the trace elements. Results: The mean serum level of Zn was lower in the Group 1 (hemodialysis group) children than in the children of Group 2 (on conservative management) and group 3 (healthy children) (p<0.001), but the difference was not significant between Groups 2 and 3. No significant differences in serum levels of Cu were found among the three groups. The serum level of Zn was lower in Subgroup B than in Subgroup A (p<0.001). The correlation test showed that there was an inverse linear relation between the length of time the child was on the hemodialysis regimen and serum Zn levels. Conclusion: Chronic hemodialysis may lead to abnormalities in the serum levels of some trace elements in children with CRF that increase in severity with increasing duration of hemodialysis. Deficiencies of these trace elements – zinc in particular – may contribute to various conditions and symptoms in children undergoing chronic hemodialysis.  相似文献   
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