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Background and purpose

Femoral head necrosis (FHN) is a debilitating disease which seriously affects the patients’ quality of life, especially the young. The porous tantalum rod has the advantages of high volumetric porosity, low modulus of elasticity, and excellent osteoinduction, with exceptional biocompatibility and safety record in clinical application, which makes it an ideal choice for FHN patients. However, there has not been a systematic analysis for its efficacy and safety.

Methods

This meta-analysis of six randomized controlled trials and controlled clinical trials with 256 participants was performed to investigate the efficacy and safety of porous tantalum rod, by means of comparing with vascularized or non-vascularized bone grafting.

Results

Porous tantalum has its advantages in functional evaluation of Harris Hip Score, with a significant lower incidence of femoral head collapse. The surgical blood loss is low and the operative time is short with no increase in complication rate.

Interpretation

Our preliminary analysis provided that the porous tantalum rod was a less invasive method and was effective and well tolerant for early-stage FHN patients. Further specially designed clinical trials for long-term follow-up and socioeconomic assessment are needed before a final determination.  相似文献   
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Dysphonia Severity Index (DSI) is an objective multi-parametric measurement of voice quality, which has been widely used in different countries. Studies indicate that DSI may be influenced by vocal pathology, age and geographical factors, whereas gender does not significantly affect DSI. The purpose of this study was to investigate the effects of gender and age on the DSI and related parameters in a Shanghainese population. The present study measured the DSI and the parameters maximum phonation time (MPT), highest fundamental frequency (HF0), lowest intensity (LI) and Jitter in 187 Shanghainese subjects, including 106 young adults aged 18–23 years (52 males and 54 females) and 81 children aged 7–9 years (44 boys and 37 girls). Two-way analysis of variance indicated that HF0 was significantly higher in female subjects than in male subjects, in both young adults and children. Gender was not significantly associated with MPT, LI, jitter or DSI. With regard to age, MPT and DSI were significantly higher in young adults than in children, and HF0 and LI were significantly lower. No significant associations between age and jitter were detected. In terms of clinic significance, the results of this study may contribute to the establishment of a normal reference range for Shanghainese DSI values, and the influence of gender and age on DSI and its separate components.  相似文献   
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Post-traumatic stress disorder (PTSD) is an anxiety disorder caused by traumatic experience, which affects a patient’s quality of life and social stability. The objective of this study was to determine the apoptosis-related genes B-cell lymphoma 2 (Bcl-2) and BCL2-associated X (Bax) expressions and medial prefrontal cortex (mPFC) neuronal apoptosis after PTSD in rat model and therefore to provide experimental evidence to reveal PTSD pathogenesis. The single-prolonged stress (SPS) method was used to set up the rat PTSD models. Chemiluminescence was used to determine serum corticosterone levels. Neuronal apoptosis was detected using transmission electron microscopy, Hoechst staining, and terminal deoxynucleotidyl transferase dUTP nick end labeling staining. Immunohistochemistry, immunofluorescence, RT-PCR, and Western blot were used to detect the expressions of Bcl-2 and Bax protein in mPFC. Our results showed an increased mPFC neuronal apoptosis after SPS stimulation. The number of apoptotic cells peaked on day 7. The expressions of Bcl-2 and Bax peaked on days 4 and 7. The Bcl-2/Bax ratio elevated on days 1 and 4 but decreased markedly on day 7. These results indicated that SPS stimulation increased the number of apoptotic neurons, up-regulated the expressions of Bcl-2 and Bax, and altered the Bcl-2/Bax ratio in the mPFC of PTSD rats.  相似文献   
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