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991.
The aim was to study the characteristics of lateral mandibular horizontal deviations during opening–closing movements and their association with TMJ sounds of the clicking type. Subjects were 28 healthy volunteers and 38 patients diagnosed with MRI imaging as having TMJ disc dysfunction, 22 with disc displacement without (DD) and 16 as having disc displacement with reduction (DDR). TMJ sounds were recorded with miniature microphones placed in the ear canals, and jaw movements were documented with a kinesiograph. A sign, unbalanced lateral deviation (ubd) was defined as a rapid, short duration, change in jaw movement direction from, and back to, a smooth deviation path in the horizontal plane. The hypotheses were that degrees of maximal deviations, proportions of unbalanced deviation (ubd) and such deviation associated with TMJ sounds (ubdS), differ between healthy subjects and patients with DD or DDR. Comparisons between groups were made using one‐way anova and chi‐square analysis, as appropriate. No differences were found between groups regarding degree of lateral deviation per se. The proportions of ubd and ubdS were significantly higher in patients with DDR than in healthy subjects and than in patients with DD (P < 0·001), but no such differences were found between healthy subjects and patients with DD. For prediction of DDR, the sensitivity and specificity of the sign ubdS were found to be 68·8% and 89·3%, respectively. For the sign ubd, they were 100·0% and 64·3%. This indicates that the sign ubdS has diagnostic value in screening for DDR.  相似文献   
992.
Autologous cells suffer from limited cell number and senescence during ex vivo expansion for cartilage repair. Here we found that expansion on extracellular matrix (ECM) deposited by fetal synovium-derived stem cells (SDSCs) (FE) was superior to ECM deposited by adult SDSCs (AE) in promoting cell proliferation and chondrogenic potential. Unique proteins in FE might be responsible for the rejuvenation effect of FE while advantageous proteins in AE might contribute to differentiation more than to proliferation. Compared to AE, the lower elasticity of FE yielded expanded adult SDSCs with lower elasticity which could be responsible for the enhancement of chondrogenic and adipogenic differentiation. MAPK and noncanonical Wnt signals were actively involved in ECM-mediated adult SDSC rejuvenation.  相似文献   
993.
目的调查医科研究生对本校学习风气的评价,并具体调查了研究生对自己学习(科研)期望和态度的看法,为相关管理部门加强教育引导提供依据。方法应用自制问卷,比较某医科大学研究生总体、不同性别、不同年级、不同录取类别、不同培养层次、不同学位类型、不同专业对学风、学习期望、学习态度的看法。结果医科研究生总体对于本校学习风气的评价主要为"较好"(48.3%),其次是"一般"(25.7%)和"很好"(22.3%);不同专业、不同年级、不同录取类别(χ2=49.188,24.517,29.248;P<0.05)之间不同。研究生总体对自己学习(科研)的期望主要是优秀(43.7%)和良好(42.2%);不同年级、不同培养层次、不同录取类别之间有差异(χ2=37.788,35.836,61.120;P<0.05)。研究生总体对自己学习(科研)态度的评价主要为比较严谨(60.5%)和很严谨(19.7%);不同年级、不同培养层次、不同录取类别之间有差异(χ2=17.350,15.423,40.327;P<0.05)。结论医科研究生整体学风较好,尤其是公共卫生与预防医学专业和计划研究生;整体学习期望较高,学习态度较好。  相似文献   
994.
Three invasive Streptococcus pneumoniae strains nonsusceptible to linezolid were isolated in the United States between 2001 and 2012 from the CDC''s Active Bacterial Core surveillance. Linezolid binds ribosomal proteins where structural changes within its target site may confer resistance. Our study identified mutations and deletions near the linezolid binding pocket of two of these strains within the rplD gene, which encodes ribosomal protein L4. Mutations in the 23S rRNA alleles or the rplV gene were not detected.  相似文献   
995.
Struma ovarii, a rare varity of ovarian neoplasm, belongs to the group of monodermic teratomas mainly composed of thyroid tissue. The preoperative diagnosis is always difficult to identify without histopathological examination. Surgery is the only treatment because malignant alteration is possible and thyroid hyperactivity or hyperthyroidism may occur. Our patient, a post-menopausal women, had unilateral, large, multiloculated ovary mass of 20cm×15cm×10cm size without any thyroid hyper activity. The radical excision of the tumor with right ovary was preformed. Histopathological examination confirmed struma ovarii. The post-operative period was uneventful and her thyroid function remained normal.  相似文献   
996.
997.
998.
目的:为深入分析研究本草纲目中的药物警戒思想提供新方法。方法:基于本草纲目金陵本文献著作设计了药物警戒数据库,阐述了数据库建立的要求和存储模型的选取,以及数据库的概念和逻辑设计。结果:在此数据库的基础上可建立知识发现系统,应用数据挖掘算法,对本草纲目中的药物警戒思想进行分析。结论:本草纲目药物警戒思想数据库的建立可以为深入研究药物警戒思想提供方便、准确的手段,此方法也可应用于其他文献著作研究。  相似文献   
999.
1000.
To examine the potential roles of melatonin in drought tolerance, we tested the effects of its long‐term exogenous application on ‘Hanfu’ apple (Malus domestica Borkh.). When 100 μm melatonin was added to soils under drought conditions, the resultant oxidative stress was eased and leaf senescence was delayed. This molecule significantly reduced chlorophyll degradation and suppressed the up‐regulation of senescence‐associated gene 12 (SAG12) and pheophorbide a oxygenase (PAO). Such treatment also alleviated the inhibition of photosynthesis brought on by drought stress. We also investigated quenching and the efficiency of Photosystem II (PSII) photochemistry under dark and light conditions and found that melatonin helped to maintain better function of PSII under drought. The addition of melatonin also controlled the burst of hydrogen peroxide, possibly through direct scavenging and by enhancing the activities of antioxidative enzymes and the capacity of the ascorbate–glutathione cycle. Thus, understanding this effect of melatonin on drought tolerance introduces new possibilities to use this compound for agricultural purposes.  相似文献   
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