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131.
同种异体肌腱修复膝关节韧带损伤2年随访报道   总被引:1,自引:0,他引:1  
目的探索应用同种异体肌腱修复膝关节韧带损伤的临床疗效,避免取自体肌腱造成的膝关节周围组织再损伤和并发症。方法采用经深低温冷冻加γ射线照射处理的同种异体骨-髌腱-骨移植,关节镜下修复膝关节交叉韧带损伤30例,前交叉韧带16例、后交叉韧带9例,前、后交叉韧带一期修复5例。其中1例镜下行半月板缝合,15例行半月板部分切除或完全切除,1例合并胫腓骨骨折,交锁髓内钉固定术后3周行交叉移植修复,3例合并髌骨骨折,与交叉韧带在关节镜下同时修复。结果29例患者获得2年以上随访,采用Lysholm膝关节功能评分法评估患膝手术前后的功能,术前平均36分,术后平均85分,优良率86%。客观检查,前抽屉试验阳性,术前21例,术后弱阳性2例,后抽屉试验阳性,术前14例,术后弱阳性3例,Lachman试验阳性,术前21例,术后弱阳性4例,术后遗留膝关节运动后疼痛2例,可忍受,膝关节屈曲活动受限(5°~20°)2例。其中7例术后1~2年取内固定或镜下行韧带固缩过程中,取少许异体髌腱活检,结果已全部转变为正常腱性组织。结论应用同种异体骨-髌腱-骨组织修复膝关节韧带损伤,术后通过系统的康复治疗,能有效恢复膝关节功能。  相似文献   
132.
目的:探讨发育性髋关节发育不良(DDH)髋臼的变化.方法:采用管型石膏固定方法制作动物模型,取经X线检查存在DDH的大耳白兔,行ECT检查后解剖双侧髋臼.以GREENHILL方法进行测量.分别沿长短径并与两径平行取材切片观察其组织学改变.结果:ECT检查结果显示病变髋臼核素浓聚明显低于对照侧.病变髋臼向后上方延长,失去其近似圆形的结构而呈椭圆形.组织学观察,沿长径的切片显示病变髋臼后上缘关节软骨外翻,其关节软骨生长柱方向也发生改变,异位关节软骨明显增厚;而沿短径的切片可以看到透明软骨去机化及向纤维软骨转化.结论:DDH动物模型中存在微循环的改变,软骨翻转导致髋臼后上方的延长.  相似文献   
133.

目的:对比角膜板层刀制瓣的前弹力层下准分子激光角膜磨镶术(SBK)、飞秒激光制瓣的SBK术(FS-SBK)与飞秒激光小切口角膜基质透镜取出术(SMILE)对近视中央角膜内皮细胞的短期及长期影响。

方法:我院近视34例34眼行SBK术; 41例41眼行FS-SBK术; 49例49眼行SMILE术,术前和术后1wk,1a利用SP-1P型非接触角膜内皮显微镜检查角膜内皮细胞,统计分析各组中央角膜内皮细胞密度(ECD)、内皮细胞面积的变异系数(CV)和六边形内皮细胞百分比。

结果:三组间术前、术后1wk,1a裸眼视力及屈光度均无差异(P>0.05)。术后1wk三组中央ECD均较术前减少(P<0.01),术后1a各组均较术前无差异(P>0.05); 术前及术后各随访时间点,三组间中央角膜内皮细胞面积CV及六边形内皮细胞百分比均无差异(P>0.05); 不同组内,术前及术后各随访时间点结果均无差异(P>0.05)。

结论:SBK、FS-SBK和SMILE手术对近视内皮细胞的安全性确切,术后早期各组中央角膜ECD均轻度降低,1a后恢复; 术后各组中央角膜内皮细胞面积CV及六边形内皮细胞百分比较术前无明显改变。  相似文献   

134.
Surface morphology is an important indicator of malignant potential for solid-type lung nodules detected at CT, but is difficult to assess subjectively. Automated methods for morphology assessment have previously been described using a common measure of nodule shape, representative of the broad class of existing methods, termed area-to-perimeter-length ratio (APR). APR is static and thus highly susceptible to alterations by random noise and artifacts in image acquisition. We introduce and analyze the self-overlap (SO) method as a dynamic automated morphology detection scheme. SO measures the degree of change of nodule masks upon Gaussian blurring. We hypothesized that this new metric would afford equally high accuracy and superior precision than APR. Application of the two methods to a set of 119 patient lung nodules and a set of simulation nodules showed our approach to be slightly more accurate and on the order of ten times as precise, respectively. The dynamic quality of this new automated metric renders it less sensitive to image noise and artifacts than APR, and as such, SO is a potentially useful measure of cancer risk for solid-type lung nodules detected on CT.  相似文献   
135.
136.
New data on the mechanisms of movements of the shoulder girdle and humerus of bats are described; potential mobility is compared to the movements actually used in flight. The study was performed on the basis of morphological and functional analysis of anatomical specimens of 15 species, high speed and high definition filming of two species and X‐ray survey of Rousettus aegyptiacus flight. Our observations indicate that any excursions of the shoulder girdle in bats have relatively small input in the wing amplitude. Shoulder girdle movements resemble kinematics of a crank mechanism: clavicle plays the role of crank, and scapula—the role of connecting rod. Previously described osseous “locking mechanisms” in shoulder joint of advanced bats do not affect the movements, actually used in flight. The wing beats in bats are performed predominantly by movements of humerus relative to shoulder girdle, although these movements occupy the caudal‐most sector of available shoulder mobility. Anat Rec, 296:382–394, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
137.
《Injury》2018,49(2):359-363
IntroductionBone mineral density and fracture morphology are widely discussed and relevant factors when considering the different treatment options for proximal humerus fractures. It was the aim of this study to investigate the influence of local bone quality on fracture patterns of the Neer classification as well as on fracture impaction angle in these injuries.Materials and methodsAll acute, isolated and non-pathological proximal humerus fractures admitted to our emergency department were included. The fractures were classified according to Neer and the humeral head impaction angle was measured. Local bone quality was assessed using the Deltoid Tuberosity Index (DTI). The distribution between DTI and fracture pattern was analysed.Results191 proximal humerus fractures were included (61 men, mean age 59 years; 130 women, mean age 69.5). 77 fractures (40%) were classified as one-part, 72 (38%) were two-part, 24 (13%) were three- and four-part and 18 (9%) were fracture dislocations. 30 fractures (16%) were varus impacted, whereas 45 fractures (24%) were classified as valgus impacted. The mean DTI was 1.48. Valgus impaction significantly correlated with good bone quality (DTI ≥ 1.4; p = 0.047) whereas no such statistical significance was found for the Neer fracture types.DiscussionWe found that valgus impaction significantly depended on good bone quality. However, neither varus impaction nor any of the Neer fracture types correlated with bone quality. We conclude that the better bone quality of valgus impacted fractures may be a reason for their historically benign amenability to ORIF. On the other hand, good local bone quality does not prevent fracture comminution.  相似文献   
138.
Understanding the constraints, including biological ones, that may influence mathematical development is of great importance because math ability is a key predictor of career success, income and even psychological well-being. While research in developmental cognitive neuroscience of mathematics has extensively studied the key functional regions for processing numbers, particularly the horizontal segment of intraparietal sulcus (HIPS), few studies have investigated the effects of early cerebral constraints on later mathematical abilities. In this pre-registered study, we investigated whether variability of the sulcal pattern of the HIPS, a qualitative feature of the brain determined in-utero and not affected by brain maturation and learning, accounts for individual difference in symbolic and non-symbolic number abilities. Seventy-seven typically developing school-aged children and 21 young adults participated in our study. We found that the HIPS sulcal pattern, (a) explains part of the variance in participant’s symbolic number comparison and math fluency abilities, and (b) that this association between HIPS sulcal pattern and symbolic number abilities was found to be stable from childhood to young adulthood. However, (c) we did not find an association between participant’s non-symbolic number abilities and HIPS sulcal morphology. Our findings suggest that early cerebral constraints may influence individual difference in math abilities, in addition to the well-established neuroplastic factors.  相似文献   
139.
The anatomical structure linking the patella and the tibia is called the “patellar ligament” in the international nomenclature. This term is well accepted yet can be a source of confusion for non-specialists. This is because the priority role of this structure is not to maintain joint stability, the primary role of the cruciate ligaments and the collateral ligaments, but rather to prolong the mechanical action of the quadriceps muscle onto the leg skeleton beyond the “patellar sesmoid”. Patellar tendon injuries are a common observation in sports medicine. The proximal third of the tendon below the patella is most generally involved. This highly frequent tendinopathy sometimes termed an “insertion” tendiopathy. Based on 100 consecutive magnetic resonance imaging studies and cadaveric dissection, we confirm that the insertion of the patellar tendon is situated on the anterior aspect of the patella and not the tip. We describe two anatomical variants of the healthy patellar tendon (type 1 and 2) that should not be confused with a site of tendinopathy. The anatomical limits between tendinous tissue and infrapatellar adipose body (the Hoffa adipose ligament), notably on the upper third is still debated and merits further work.  相似文献   
140.
An increase in growth rates of children suffering from growth hormone deficiency (GHD) subjected to recombinant growth hormone treatment (rGHT) was shown to be accompanied by acceleration of metabolic processes that may stimulate oxygen consumption in various organs and tissues. Therefore, oxygen-transporting properties of RBC should undergo considerable changes during the rGHT. The aim of this study was to examine the effects of rGHT on erythrocyte shape and hemoglobin state in GHD children. The level of oxyhemoglobin (Oxy-Hb) in RBC was analyzed by Raman spectroscopy. The RBC count, mean corpuscular hemoglobin (MCH), mean corpuscular volume (MCV) and other parameters were calculated. The blood of eleven treatment-naive prepubertal children with GHD (aged 3–9, median 5.7 years) was examined and compared with control group (aged 5–7; median 6.0 years) at three time points: 0, 3 and 12 months of rGHT. Before rGHT, the MI in GHD children was higher (median 0.48 vs 0.14 p = 0.0018) and the RBC count was lower (median 4.20 vs 4.96 1012 cells/L p = 0.0022) than in control group. After the treatment, cell count in GHD patients did not differ significantly from the control group, but Oxy-Hb level became higher (median 0.64 vs 0.41 p = 0.0075). During rGHT, MCV decreased (median 80.3 vs 83.2 μm3 p = 0.0231). Morphological and functional characteristics of erythrocytes in GHD children were shown to differ significantly from the healthy control group. A twelve-month rGHT partially improved some of the studied parameters but Oxy-Hb level and echinocyte count remained high.  相似文献   
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