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41.
42.

Objectives  

Because of their structural, anti-inflammatory and antithrombic properties, longchain n-3 fatty acids may be key factors in the aging process. We sought to elucidate the association between intake of long-chain n-3 fatty acids and/or fish and cognitive function evaluated 13 years after dietary assessment.  相似文献   
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BackgroundThe purpose of this study was to compare initial fixation strength between various stemless and stemmed humeral components and to correlate implant fixation strength with bone mineral density (BMD).MethodsFive humeral stem designs were investigated: Stemless-A (four hollow fins), Stemless-B (central body, three solid fins), Stemless-C (central screw, peripheral rim-fit), Short stem (50 mm), and Standard stem (130 mm). Fifty cadaveric human humerii were obtained and divided into five groups. BMD within the humeral head was determined for all samples. The mean BMD was similar between groups. The 25 samples with the lowest and highest BMDs were categorized as “Low” and “High,” respectively, with a BMD threshold of 0.35 g/cm2, creating BMD subgroups. After implantation, each sample underwent a standardized biomechanical testing protocol, with axial loading followed by torsional loading. Sensors attached to the specimen recorded micromotion throughout testing. Axial loading consisted of cyclic loading for 100 cycles at 3 peak forces (220, 520, and 820 N). Torsional loading consisted of 100 cycles of internal/external rotation at 0.1 Hz at 6 peak torques, or until failure (±2.5, 5, 7.5, 10, 12.5, and 15 Nm). Failure was defined as the torque at which any bone fracture, implant detachment from anchor/stem, or an excess of 50° internal/external rotation occurred. Groups and BMD subgroups were compared.ResultsAt maximal axial loading, Stemless-B demonstrated greater micromotion (540 μm) than Stemless-C (192 μm) (P = .003). Stemless-B and Stemless-A (387 μm) also had greater micromotion than Short stem (118 μm, P < .001, P = .03) and Standard stem (85 μm, P < .001, P = .01). When comparing low-BMD samples at maximal axial loading, these differences were accentuated, but comparison of high-BMD samples showed no significant differences between groups. Torsional testing demonstrated that Standard stem failed at greater torque (7.2 Nm) than Stemless-B (2.3 Nm, P < .001), Stemless-A (1.9 Nm, P < .001), and Stemless-C (3.9 Nm, P = .01). When comparing torsional testing results of low-BMD samples, both Standard stem and Short stem failed at greater torque than Stemless-B (P = .02, P = .003) and Stemless-A (P = .03, P = .004) but failed at a similar torque to Stemless-C. Torsional testing of high-BMD samples showed that Standard stem failed at a greater torque than all stemless designs.ConclusionStemless humeral implants should be used with caution in low-BMD settings (<0.35 g/cm2). A central screw and peripheral rim-fit stemless anchor design demonstrated greater fixation strength at low BMD when compared with other designs, while all stemless designs performed similarly at high BMD.Level of evidenceBasic Science Study; Cadaveric Study  相似文献   
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47.

Objectives

Research concerning the link between dairy product intake and cognition is scant while experimental studies suggest links through various biological mechanisms. This study’s objective was to examine the cross-time associations of total and specific dairy product consumption with cognitive performance in aging adults. We also explored compliance with dairy intake recommendations in France.

Design

The study was based on the «Supplémentation en Vitamines et Minéraux Antioxydants» randomized trial (SU.VI.MAX, 1994-2002) and the SU.VI.MAX 2 observational follow-up study (2007-2009).

Setting

A general-population cohort in France.

Participants

N=3,076 participants included in both the SU.VI.MAX and SU.VI.MAX 2 studies.

Measurements

Dairy product consumption was estimated using repeated 24h records (1994-1996; mean=10 records, SD=3). Cognitive performance was assessed by neuropsychologists after an average of 13 years post-baseline via a battery of six validated tests. Mean age at the time of the cognitive function evaluation was 65.5 (SD=4.6) years. Principal component analysis revealed factors for verbal memory and working memory. Associations of energy-adjusted dairy product consumption and compliance with the respective dietary guidelines with subsequent cognitive impairment were examined using ANCOVA, providing mean differences (95% confidence intervals, CI) according to tertiles (T), adjusted for confounders including overall dietary patterns.

Results

Total dairy product consumption was not associated with cognitive function. However, milk intake was negatively associated with verbal memory performance: mean difference T3 versus T1= -0.99 (-1.83, -0.15). Among women, consuming more than the recommended amount of dairy was negatively associated with working memory performance: excess versus adequate = -1.52 (-2.93, -0.11).

Conclusion

Our results indicate that dairy products consumption and especially compliance with dietary guidelines regarding dairy product intake are differentially associated with performance in specific cognitive domains after a comprehensive adjustment for lifestyle factors, health status markers and dietary patterns. Further longitudinal research is needed given the limited data available.
  相似文献   
48.
Mounting evidence suggests that bone marrow-derived cells (BMDC) contribute to tumor growth, angiogenesis, and metastasis. In acute reactions to cancer therapy, several types of BMDCs are rapidly mobilized to home tumors. Although this host reaction to therapy can promote tumor regrowth, its contribution to metastasis has not been explored. To focus only on the effects of chemotherapy on the host, we studied non-tumor-bearing mice. Plasma from animals treated with the chemotherapy paclitaxel induced angiogenesis, migration, and invasion of tumor cells along with host cell colonization. Lesser effects were seen with the chemotherapy gemcitabine. Conditioned medium from BMDCs and plasma from chemotherapy-treated mice each promoted metastatic properties in tumor cells by inducing matrix metalloproteinase-9 (MMP9) and epithelial-to-mesenchymal transition. In mice in which Lewis lung carcinoma cells were injected intravenously, treatment with paclitaxel, but not gemcitabine or vehicle, accelerated metastases in a manner that could be blocked by an MMP9 inhibitor. Moreover, chimeric mice reconstituted with BMDC where MMP9 activity was attenuated did not support accelerated metastasis by carcinoma cells that were pretreated with chemotherapy before their introduction to host animals. Taken together, our findings illustrate how some chemotherapies can exert prometastatic effects that may confound treatment outcomes.  相似文献   
49.
The aim of our study was to examine the effect of individual schemes of multimodal analgesia on indicators of immunity and inflammation markers after operations on the colon. Patients of group 1 (n=15) received paracetamol, lornoxicam and epidural ropivacaine, 2nd group of patients (n=15)-paracetamol, epidural ropivacaine and tramadol. Comparison group (n=10) patients underwent patient controlled analgesia by promedol. Before surgery, 1st and 3rd days after surgery we examined the contents of cytokines in plasma: interleukin 12p70, interleukin 10, interleukin 6, and TNF. Before surgery and at 5-7 days after surgery indicators of cellular, fagocytal and humoral immunity were monitored. Before surgery patients with colorectal cancer revealed changes in the indices of different components of immunity, as well as an increase in pro-and anti-inflammatory cytokines compared with healthy donors. Multimodal analgesia in patients after operations on the colon is not accompanied by changes in plasma concentrations of cytokines and parameters of immune status in comparison with monoanalgesia by promedol.  相似文献   
50.
About 70% of Ghanaians depend on Alternative health practice for their primary health care needs. Hence, there is the need to streamline and regulate these practices. Graduates from the Faculty of Pharmacy and Pharmaceutical Sciences, Kwame Nkrumah University of Science and Technology (K.N.U.S.T), Kumasi-Ghana were assessed by the Professional Qualifying Examination Board of the Traditional Medicine Practice Council (TMPC), Ghana, after two years of internship training. A model of assessment took into consideration, the scope of the university training, internship and the primary health care needs of the society.  相似文献   
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