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1.
弱视是由于视觉发育关键期内各种异常的视觉经验导致单眼或双眼最佳矫正远视力低于正常同龄儿童,而眼部无明显器质性病变。目前普遍观点认为,弱视的发病机理主要源于视皮层。近年来,光学相干断层扫描(OCT)作为一种先进的活体成像技术,促进了对视网膜形态结构的大量研究,同时也被应用到弱视的研究领域。陆续有不同的研究人员利用OCT发现弱视患者眼底视网膜、脉络膜等眼部结构存在改变。笔者将对弱视眼底OCT的研究进展做一综述。  相似文献   
2.
目的 探讨肩锁关节形态学及组织结构特点。 方法 对27具成人新鲜尸体进行解剖学分析,观察肩锁关节形态,测量相关骨性结构、韧带参数,并将标本随机分为A、B两组,A组保留肩锁韧带和喙锁韧带,B组仅保留肩锁韧带,比较两组之间承受拉力的差别。 结果 锥状韧带止点中点到锁骨远端距离(42.68±6.34)mm,止点宽度(16.97±4.28)mm,中心点厚度为(5.39±0.34)mm;斜方韧带止点中点到锁骨远端度距离(20.35±4.18)mm,止点宽度(10.35±1.31)mm,中心点厚度为(5.19±0.342)mm;喙突基底底部到锁骨表面的垂直平均距离为30.75 mm,喙锁间隙平均距离为12.02 mm;锥韧带中轴长度为(15.68±3.30)mm,角度(117.25±10.80)°,而斜方韧带中轴长度为(9.67±2.25)mm,角度(75.42±11.37)°,锥状韧带和斜方韧带始点距离(8.96±3.00)mm,止点距离(13.09±3.50)mm;A组拉力平均值(610.04±51.24)N高于B组拉力平均值(560.41±44.63)N(P<0.05)。 结论 在行锁骨远端切除术时,锁骨远端切除应控制在10~30 mm之间,在喙突下方上钻孔时深度尽量不超过42 mm,肩锁关节脱位时重建喙锁韧带具有解剖学及生物力学基础。  相似文献   
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目的 测量分析正常成人下腰椎Kambin三角工作区磁共振神经显像(magnetic resonance neurography,MRN)的相关解剖数据,为下腰椎微创手术的选择和安全性评估提供参考。 方法 采用3.0 T磁共振对20名健康成年志愿者(男10例,女10例)进行腰椎L4~S1节段的MRN扫描,通过Osirix软件对图像进行神经成像并测量以下数据:神经节与上位椎弓根间距(A)、神经节与下位椎弓根间距(B)、神经根与硬膜囊夹角(α)、Kambin三角的面积(S),并对所测数据进行统计学分析。 结果 自L4~S1,同侧神经节与上位椎弓根的距离逐渐减小(P<0.05),而同侧神经节与下位椎弓根的距离无统计学差异(P>0.05);自L4~S1,同侧出口神经根与硬膜囊夹角逐渐变小,差异有统计学意义(P<0.05);自L4~S1,Kambin三角面积逐渐增大(P<0.05);此外,所有测量指标同节段左右两侧对比无统计学差异(P>0.05)。 结论 MRN技术对下腰椎Kambin三角各组成结构的解剖关系显像清晰准确,便于相关解剖测量并指导临床腰椎微创手术方法的选择和手术安全性的评估。  相似文献   
5.
The Qiang population mainly lived in Beichuan Qiang Autonomous County of Sichuan Province. It is one of the nomads in China, distributed along the Minjiang River. The Qiang population was assumed to have great affinity with the Han, the largest ethnic group in China, when it refers to the genetic origin. Whereas, it is deeply understudied, especially from the Y chromosome. Here in this study, we used validated high-resolution Y-chromosome single nucleotide polymorphisms (Y-SNPs) and short tandem repeats (Y-STRs) panels to study the Qiang ethnic group to unravel their paternal genetic, forensic and phylogenetic characteristics. A total of 422 male samples of the Qiang ethnic group were genotyped by 233 Y-SNPs and 29 Y-STRs. Haplogroup O-M175 (N = 312) was the most predominant haplogroup in the Qiang ethnic group, followed by D-M174 (N = 32) and C-M130 (N = 32), N-M231 (N = 27), and Q-M242 (N = 15). After further subdivision, O2a-M324 (N = 213) accounted for the majority of haplogroup O. Haplogroup C2b-Z1338 (N = 29), D1a-CTS11577 (N = 30). O2a2b1a1a1-F42 (N = 48), O2a1b1a1a1a-F11 (N = 35), and O2a2b1a1-M117 (N = 21) represented other large terminal haplogroups. The results unveiled that Qiang ethnic group was a population with a high percentage of haplogroup O2a2b1a1a1-F42 (48/422) and O2a1b1a1a1a-F11 (35/422), and O2a2b1a1-M117 (21/422), which has never been reported. Its haplogroup distribution pattern was different from any of the Han populations, implying that the Qiang ethnic group had its unique genetic pattern. Mismatch analysis indicated that the biggest mismatch number in haplogroup O2a2b1a1a1-F42 was 21, while that of haplogroup O2a1b1a1a1a-F11 was 20. The haplotype diversity of the Qiang ethnic group equaled 0.999788, with 392 haplotypes observed, of which 367 haplotypes were unique. The haplogroup diversity of the Qiang ethnic group reached 0.9767, and 53 terminal haplogroups were observed (The haplogroup diversity of the Qiang ethnic group was the highest among Qiang and all Han subgroups, indicating the larger genetic diversity of the Qiang ethnic group.). Haplogroup O2a2b1a1a1-F42 was the most predominant haplogroup, including 11.37 % of the Qiang individuals. Median-joining trees showed gene flow between the Qiang and Han individuals. Our results indicated that 1) the highest genetic diversity was observed in the Qiang ethnic group compared to any of the former studied Chinese population, suggesting that the Qiang might be an older paternal branch; 2) the haplogroup D-M174 individuals of Qiang, Tibetans and Japanese distributed in three different subclades, which was unable to identify through low-resolution Y-SNP panel; and 3) the Qiang had lower proportion of haplogroup D compared to Yi and Tibetan ethnic groups, showing that the Qiang had less genetic communication with them than with Han Chinese.  相似文献   
6.
Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) threatens human health. A local CA-MRSA with ST8/SCCmecIVl (CA-MRSA/J) has emerged in Japan, being associated with progression from bullous impetigo to potentially fatal invasive infection. We found that CA-MRSA/J has unique bacterial surface structures, spikes, spikes with a cap, and long spikes, reflecting clinical origins.  相似文献   
7.
ObjectivesData on the prevalence of Autism Spectrum Disorder (ASD) reveal several clinical evolutions inducing new psychiatric definitions and diagnostic practices. Thus, autism has shifted from being a rare syndrome with severe clinical forms to a new paradigm: the paradigm of “ordinary” or “invisible” autism, in terms of the frequency and the intensity of the disorders. These changes incorporate new populations into our conception of autism, with new phenotypes that pose theoretical and clinical challenges to clinicians. In response, we propose the hypothesis — based on psychoanalytic theories of psychic structures — of an “ordinary autism” as a definition of a non-prototypical autistic psychic functioning that falls outside the DSM diagnostic framework. This idea seems to provide us new theoretical references that nourish our practices as well as fundamental research.MethodFirst, we will review the nosographic mutations of the DSM-5 and their implications for non-prototypical psychic modes of functioning of autistic people that may not be contained within the autism spectrum's blurry boundaries — especially for the adult population without intellectual delay and in the case of complicated differential diagnosis for clinical and societal reasons. Next, we will discuss the definition of “ordinary” or “invisible” autism in a psychoanalytic structural model, as a possible epistemological orientation for identifying and designing practice with the clinical heterogeneity of autism outside the boundaries of psychiatric ASD.ResultsThe autistic population targeted by the DSM-5 criteria is different from that previously defined by DSM-IV. This leads to two consequences: on the one hand, autistic modes of functioning are not limited to individuals who have been diagnosed with Autism Spectrum Disorders as defined by the DSM-5; thus individuals with autism do not have access to the diagnosis of ASD or are given other diagnoses. The alternative diagnoses proposed by the DSM-5 that attempt to correct this diagnostic exclusion — such as Social (Pragmatic) Communication Disorder — are unsatisfactory. Therefore, there is an entire segment of the autistic population that has subclinical, non-prototypic autistic manifestations or more subtle phenomena discernible in the broader autistic phenotype or sub-threshold autism spectrum that does not have access to the ASD diagnosis and raises differential diagnostic issues. On the other hand, it appears that the autism spectrum brings together extremely different entities and false positives such as schizophrenia and schizophrenic spectrum personality disorders under one diagnostic rubric. Then, the differential problem appears central: both at the theoretical level and in diagnostic practices. The recognition of these limits should encourage us to promote research and clinical applications on this subject. One solution that we envisage is to be found in an extension of Maleval's structural psychoanalytical model: we propose the notion of “ordinary autism” — an echo of ordinary psychosis — to define attenuated or compensated non-prototypical autistic phenotypes, increasingly frequent and with fewer “extraordinary” phenomenological expressions than the classic cases of autism which now call into question the relationship between the normal and the pathological.Discussion“Ordinary autism” seems to offer clinicians the opportunity to formalize the new contemporary and extensive clinical reality of autism. This term situates itself within a theoretical model whose current and future developments might help us respond to clinical and diagnostic issues, but also to therapeutic and societal ones. We propose to continue on the path of the operationalization of these theoretical models in order to identify autistic structural constants that could be found throughout the “ordinary” clinic of autism and could serve as differentiating tools for diagnosis as well as a support in developing and refining therapeutic practices.ConclusionWe conclude that there is an urgent need to conceive of “ordinary autism” to provide us with reference points to respond to new clinical issues, but also to reintroduce respect for the autistic person in his or her subjectivity to the center of our therapeutic practices.  相似文献   
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9.
目前在中医界已发布的冠心病痰湿证辨证标准是以主症、次症形式定性地给出,存在主观性较强的问题。本文引入约束隐结构分析,该方法将主症、次症的语义作为约束条件加入隐结构分析过程,得到含有主症、次症语义约束的定量化中医证候辨证规则。使用该方法对冠心病痰湿证患者556条无标签数据的分析,得到其约束隐结构模型,最后建立定量化痰湿证辨证规则,舌胖边有齿痕(3.16)、苔腻(3.12)、苔白滑(4.72)、胸闷(1.73)、脉濡或滑(6.04);次症:肢体困重(0.48)、口黏(0.63)、体胖(0.49)、大便粘滞(1.38)、脘腹痞满(0.97)、面色晦浊(0.79)、嗜睡(1.18)、纳差(1.07)。与经典隐结构模型得到规则和中医界已发布的定性化辨证规则相比,约束隐结构得到的规则客观性强,具有可重复性。在证候类大小、规则的量化合理度上较好地反映了主症、次症的特点,得到的规则切合中医实际,为冠心病痰湿证辨证标准的定量化研究提供帮助和参考。  相似文献   
10.
This paper investigates the effect of polymer modifiers (re-dispersible powder, multifunctional additives, methylhydroxyethylcellulose) on the rheological behavior of emulsions, saturated of calcium hydrosilicates to simulate a hydrating cement structure. The subjects of the study were modified emulsions which had varied concentrations of each additive and they were examined comparatively to a base emulsion. Tests were performed with a CR-rheometer (“Himpribor-1”, Tula, Russia) applying the Searle measuring principle at various shear rates to characterize viscosity properties. The performance of modified mixtures within the operating period was analyzed by using two parameters—effective viscosity (η) and the proportion of structural failure (|m|). The test results showed that the most important factor influencing rheological characteristics is the addition of methylhydroxyethylcellulose additive—the higher additive amount in the emulsion, the higher the viscosity. Furthermore it was noted in the work that adding olefin sulfonate sodium salt causes reduced viscosities as well as lower shear moduli. If ethylhydroxyethylcellulose and ethylene vinyl acetate additives are used in the same mixture together, the rate of structural failure |m| can be relatively similar and low regardless of whether the mixture has large or small viscosity values.  相似文献   
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