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51.
本实验通过对10只家兔双侧推动脉结扎,观察手术前后脑干听觉诱发电位(BAEPs)的变化[1]。结果发现:动物在推动脉结扎后,随时间延长BAEPs各波的波幅逐渐减压,潜伏期逐渐延长;上述变化持续进行40分钟,以后无大变化。提示:BAEPs可以客观地反映椎基底动脉的供血情况。本项研究为临床用BAEPs诊断椎基底动脉供血不足,提供了一项理论依据。  相似文献   
52.
BackgroundRestricted kinematically-aligned total knee arthroplasty (KA-TKA) is a reasonable modification to avoid the alignment outlier that may cause implant failure. However, despite a noted high incidence of constitutional varus in Japanese individuals, there has been no investigation into how many knees require the restriction in restricted KA-TKA (RKA-TKA) among Japanese patients. Therefore, we conducted a study using preoperative long-leg radiograms.MethodsWe studied long-leg radiographs of 228 knees in 114 consecutive patients. The numbers of knees within the safety range and their corrective osteotomy angle in the restriction algorithms advocated by Almaawi et al. (2017) and MacDessi et al. (2020) were evaluated.ResultsAccording to the algorithms used by Almaawi et al. and MacDessi et al., out of 228 knees, 46 (20%) and 39 (17%) fell within the safety range, respectively. The mean correction angles of the hip-knee-ankle angle, lateral distal femoral angle and medial proximal tibial angle were 2.8 ± 3.4°, 0.4 ± 1.4° and 2.4 ± 2.8° in the algorithm used by Almaawi et al., while they were −4.9 ± 4.7°, 1.1 ± 2.5° and −6.0 ± 3.4° in the algorithm used by MacDessi et al. Most of the knees needed to be restricted in order to perform RKA-TKA, regardless of the algorithm used.ConclusionsBased on a preoperative analysis of long-leg radiograms in a Japanese population, most knees fall out of the safety range in RKA-TKA. Surgeons must consider whether to allow component outlier or to perform corrective osteotomy that likely requires soft tissue release.  相似文献   
53.
目的 探讨术前颈椎过伸功能与颈椎后路单开门椎管扩大成形术后前凸角度丢失的关系。方法 回顾性分析首都医科大学大兴教学医院骨科2017年1月-2018年12月58例行颈椎后路单开门椎管扩大成形术患者临床资料,其中男45例、女13例,年龄49~85岁(平均64.8岁)。术前测量患者中立侧位X线片上的T1倾斜角、矢状面垂直轴(SVA),以及中立侧位、过伸位X线片的C2~C7 Cobb角。随访12~24个月,术后再次测量中立侧位X线片上的C2~C7 Cobb角。术前颈椎过伸功能测量值为术前过伸位X线片C2~C7 Cobb角度减去术前中立侧位X线片C2~C7 Cobb角。前凸角度丢失量为术前中立侧位片C2~C7 Cobb角减去末次随访时中立侧位片C2~C7 Cobb角。依据58例患者术前颈椎过伸功能均值(8.7°)分为两组,≥8.7°为A组,<8.7°为 B 组。比较两组患者术前及术后影像及临床资料,同时对58例患者的影像学资料与临床资料进行相关性分析。结果 A组25例患者年龄54~83岁,B组33例患者年龄49~85岁,两组患者术前年龄、性别、疾病种类差异均无统计学意义(P值均>0.05)。术前A组颈椎过伸功能(14.09°±4.75°)大于B组(4.62°±2.54°),A组T1倾斜角(17.00°±3.40°)小于B组(29.68°±6.34°),颈椎前凸角度丢失[1.10(-0.85,4.00)]小于B组[8.60 (7.70,12.40)],差异均有统计学意义(P值均<0.01)。颈椎过伸功能与前凸角度丢失之间呈负相关(r=-0.965, P<0.01),T1倾斜角与前凸角度丢失之间呈正相关(r=0.954, P<0.01),颈椎过伸功能与T1倾斜角呈负相关(r=-0.900, P<0.01);SVA与T1倾斜角、颈椎过伸功能、术后前凸角度丢失均无相关性(r=-0.065、0.216、-0.202, P>0.05)。术后JOA评分改善率与过伸角度变化、SVA及T1倾斜角均无相关性(r=0.201、-0.034、-0.213, P值均>0.05)。A组术后JOA改善率为69%±23%,B 组术后JOA改善率为62%±23%,两组差异无统计学意义(t=1.147, P>0.05)。术后Odom's分级评价A组优良率为88.0%(22/25),B组优良率为63.6%(21/33),差异有统计学意义(χ2 =4.403, P<0.05)。结论 对于后路单开门椎管扩大成形术患者,颈椎过伸功能与前凸角度丢失存在相关性,术前过伸功能越低,术后越易发生前凸角度丢失,可作为术前预判术后颈椎曲度变化的参数之一。  相似文献   
54.
Mabry syndrome is a glycophosphatidylinositol (GPI) deficiency characterized by intellectual disability, distinctive facial features, intractable seizures, and hyperphosphatasia. We expand the phenotypic spectrum of inherited GPI deficiencies with novel bi-allelic phosphatidylinositol glycan anchor biosynthesis class O (PIGO) variants in a neonate who presented with intractable epilepsy and complex gastrointestinal and urogenital malformations.  相似文献   
55.
BackgroundThe present article analyzes the association of the functional anterior cruciate ligament (ACL) status and the overall varus deformity and coronal tibiofemoral subluxation (CTFS) in varus OA of the knee.MethodsOne hundred consecutive knees with varus OA in 84 patients were prospectively included. Knees were divided into two groups, in accordance with the ACL status (functionally sufficient or insufficient). All included patients were potential candidates for unicompartmental knee arthroplasty with predominantly medial compartment OA. Knees with Kellgren/Lawrence ≥ grade 3 in the lateral compartment were excluded leaving 79 knees to be included in this study. Mechanical varus deformity and CTFS were evaluated on AP radiographs and valgus stress radiographs, and compared between the two groups.ResultsKnees with a functionally insufficient ACL had significantly more varus deformity on hip-to-ankle AP standing radiographs (P = .001) and on valgus stress radiographs (P = .017). CTFS on AP standing radiographs was significantly higher (P = .045) in knees with a functionally insufficient ACL. Seventy-three percent (8/11) of the ACL-insufficient knees had a varus deformity of ≥10° and 64% (7/11) of ACL-insufficient knees had CTFS ≥ 6mm. By contrast, only one patient (2%, 1/41) with an insufficient ACL had< 10° varus deformity and a CTFS of < 6mm.ConclusionFunctional ACL insufficiency in osteoarthritic varus knees is associated with greater varus deformity and more advanced CTFS. Seventy-three percent of ACL-insufficient knees had a varus deformity of ≥10° and 64% of ACL-insufficient knees a CTFS of ≥ 6mm. In the work-up for medial unicompartmental knee arthroplasty, functional ACL insufficiency is likely in knees with varus deformity of ≥10° and CTFS of ≥ 6mm.  相似文献   
56.
BackgroundPatients with a preoperative varus deformity >8 degrees are at increased risk of aseptic loosening after total knee arthroplasty. This study analyzes the effect of a tibial stem on the rate of aseptic loosening in patients with a severe preoperative varus deformity.MethodsPatients with a preoperative varus deformity of >8 degrees and 2-year minimum follow-up with a stemmed tibial component (n = 67) were matched 1:2 to patients with a similar preoperative varus deformity with a standard tibial component (n = 134). Radiolucent lines were measured on the tibia at 6 weeks, 1 year, and 2 years postoperatively using the Knee Society Radiographic Evaluation System. Failure was defined as revision due to aseptic loosening of the tibial component. Outcomes were evaluated using Student’s t-tests and log-rank tests.ResultsPatients with tibial stems had greater preoperative deformity (12.9 vs 11.3 degrees, P = .004). There was no difference in postoperative alignment (1.7 vs 2.1 degrees varus, P = .25) or tibial component angle (1.8 vs 2.1 degrees varus, P = .33). Patients with stems were more likely to have more constraint (44.8% vs 1.5%, P < .001). Progression of radiolucent lines >2 mm was observed in 17.6% (23/134) vs 5.97% (4/67) of patients in the stem group (P = .03). Rates of aseptic loosening were lower in the stem group (0% vs 5.15%, P = .05).ConclusionDespite worse preoperative deformity and higher utilization of constraint, tibial stem use in patients with severe preoperative varus deformity resulted in lower rates of aseptic loosening. Prophylactic use of stems in these patients may help increase implant survival.  相似文献   
57.
《The Journal of arthroplasty》2021,36(12):3883-3887
BackgroundTo assess how implant alignment affects unicompartmental knee arthroplasty (UKA) outcome, we compared tibial component alignment of well-functioning UKAs against 2 groups of failed UKAs, revised for progression of lateral compartment arthritis (“Progression”) and aseptic loosening (“Loosening”).MethodsWe identified 37 revisions for Progression and 61 revisions for Loosening from our prospective institutional database of 3351 medial fixed-bearing UKAs performed since 2000. Revision cohorts were matched on age, gender, body mass index, and postoperative range of motion with “Successful” unrevised UKAs with minimum 10-year follow-up and Knee Society Score ≥70. Tibial component coronal (TCA) and sagittal (TSA) plane alignment was measured on postoperative radiographs. Limb alignment was quantified by hip-knee-ankle (HKA) angle on long-leg radiographs. In addition to directly comparing groups, a multivariate logistic regression examined how limb and component alignments were associated with UKA revision.ResultsIn the Progression group, component alignment was similar to the matched successes (TCA 3.6° ± 3.5° varus vs 5.1° ± 3.5° varus, P = .07; TSA 8.4° ± 4.4° vs 8.8° ± 3.6°, P = .67), whereas HKA angle was significantly more valgus (0.3° ± 3.6° valgus vs 4.4° ± 2.6° varus, P < .001). Loosening group component alignment was also similar to the matched successes (TCA 6.1° ± 3.7° varus vs 5.9° ± 3.1° varus, P = .72; TSA 8.4° ± 4.6° vs 8.1° ± 3.9°, P = .68), and HKA was significantly more varus (6.1° ± 3.1° varus vs 4.0° ± 2.7° varus, P < .001). Using a multivariate logistic regression, HKA angle was the most significant factor associated with revision (P < .001).ConclusionIn this population of revised UKAs and long-term successes, limb alignment was a more important determinant of outcome than tibial component alignment.Level of EvidenceLevel III case-control study.  相似文献   
58.
张瑜  杜晨晖  詹海仙  尚彩玲  李瑞锋  原淑佳 《中草药》2023,54(15):4981-4991
目的 以桔梗Platycodon grandiflorus为材料,分析其叶绿体基因组特征,探究不同地区桔梗叶绿体基因组的差异及桔梗科其他物种的系统发育关系。方法 利用Illumina NovaSeq测序平台对桔梗叶绿体全基因组进行测序,完成其组装、注释和特征分析,采用生物信息学方法对不同地区桔梗进行比较基因组分析和系统发育分析。结果 桔梗叶绿体基因组全长172 770 bp,呈现典型的环状四分体结构,总GC含量为38.10%,注释到139个基因,其中蛋白质编码基因95个,核糖体RNA 8个和转运RNA 36个。经序列分析鉴定出139个SSR位点,大部分重复由A和T组成。该叶绿体基因组密码子偏好性A/U大于G/C。边界分析表明,不同地区桔梗的JLA边界区域存在差异。对比不同地区桔梗叶绿体基因组序列发现21个变异区间,包括ycf1psbCrps18rpoB等编码区以及rpl32-trnLtrnS-psbZtrnN-ycf1等非编码区。基于最大似然法(maximum likelihood method,ML)对桔梗及其他17种桔梗科植物进行系统发育分析,发现桔梗科物种形成一个单系群,各属物种聚为一束,支持率达100%。结论 桔梗科物种聚为一支与传统相符合,不同地区桔梗叶绿体基因组序列存在显著差异,为后期开展分子鉴定及群体遗传学研究提供提供科学依据。  相似文献   
59.
IntroductionGiven the prevalence and costs induced by osteoarthritis (OA), it is necessary to find a cheap and safe technique to evaluate it reliably.ObjectiveTo assess the value of the lateral dual energy X-ray absorptiometry (DXA) spine scans for the diagnosis of disc degeneration.MethodSeventy-seven individuals aged 18 and over, with or without disc degeneration, had both lateral thoracolumbar spine radiographs and DXA spine scans (≤ 6 months between both exams). Disc degeneration was assessed using the Lane score. The images of 20 randomly selected individuals were assessed by two readers.ResultsAlmost 13% of the thoracic levels were not assessable on the DXA scans. For the identification of the intervertebral levels on the DXA scans as interpretable or not, the intra-reader agreement was good (κ = 0.81) and the inter-reader agreement was fair (κ = 0.27–0.36). For the diagnostic criteria (osteophytes, disc space narrowing, osteosclerosis, overall grade), the intra-reader agreement was excellent for the radiographs (κ = 0.89–0.92), good for the DXA scans (κ = 0.64–0.83) and fair to moderate for the between-method comparison (κ = 0.25–0.44). The inter-reader agreement was moderate to good for the radiographs (κ = 0.49–0.66) and fair to good for the DXA scans (κ = 0.32–0.74). In the per patient analysis (the most severe grade), the intra-reader agreement was excellent for the radiographs (κ = 0.85–0.94), moderate to excellent for the DXA scans (κ = 0.53–0.85) and poor to good for the between-methods comparison (κ = 0.17–0.63).ConclusionOur results do not support the use of DXA scans for the assessment of thoracolumbar disc degeneration.  相似文献   
60.
Summary Racial and sex differences in the level of ending of the spinal cord of the adult have been reported. It is lower in Africans and in females. Since such differences may affect even fetuses and newborns we aimed to study in Northern Turkish neonates. The study was made on 40 full-term newborn still-births (23 male, 17 female). In all cases, the length of the vertebral column, the length of the spinal cord and the body weight were measured and the vertebral level of ending of the spinal cord was noted. It was found that the termination of the spinal cord varied from the first lumbar to the second sacral vertebra, with a mean level between L2 and L3. In female neonates, it was observed that the spinal cord ended at a slightly lower level (0.2 vertebra) than in males. Our findings approximately agreed with those of Barson [2] who studied neonates in England and of Jit and Charnalia [5] in North India. However, we found that the spinal cord ended one and half vertebrae lower in Northern Turkish neonates than in South African and South Indian subjects. The correlations between body-weight and length of the spinal cord, weight and length of the vertebral column, length of the spinal cord and length of vertebral column, length of the vertebral column and level of ending of the cord were statistically highly significant for males, females and both sexes together (p<0.001). The longer the vertebral column, the higher the termination of the spinal cord.
Niveau vertébral de la terminaison de la moelle épinière et sa relation avec la longueur de la colonne vertébrale chez le nouveau-né en Turquie du Nord
Résumé Selon la race et le sexe, les différences de niveau de la terminaison de la moelle épinière ont été rapportées chez l'adulte. Elle est plus basse chez les Africains et chez les femmes. Dès lors il se peut qu'il existe déjà des différences raciales et selon le sexe, chez le foetus et le nouveau-né. Nous nous proposons d'étudier une population de nouveau-nés du Nord de la Turquie. Cette étude est faite à partir de 40 nouveau-nés à terme, décèdes (23 garçons et 17 filles). Chez tous ces nouveau-nés, la longueur de la colonne vertébrale, la longueur de la moelle épinière et le poids ont été mesurés. Le niveau vertébral de la terminaison de la moelle épinière variait entre la première vertèbre lombaire et la deuxième vertèbre sacrée. Le niveau moyen de cette terminaison était situé entre L2 et L3. Chez les filles nouveau-nés, il était observé que la moelle épinière se terminait légèrement plus bas (0,2 vertèbre) que chez les garçons nouveaunés. Nos observations rejoignent celles de Barson [2] qui étudia des nouveaunés d'Angleterre et celles de Jit et Charnalia [5] qui étudièrent des nouveau-nés du Nord de l'Inde. Cependant, nous avons trouvé que la moelle épinière se terminait une vertèbre et demie plus bas chez les nouveau-nés de la Turquie du Nord que chez les nouveau-nés d'Afrique du Sud et d'Inde du Sud. La corrélation entre le poids des spécimens et la longueur de la moelle épinière; le poids et la longueur de la colonne vertébrale, la longueur de la moelle épinière et la longueur de la colonne vertébrale, la longueur de la colonne vertébrale et le niveau vertébral de la terminaison de la moelle épinière parmi les garçons, les filles, et dans les deux sexes, étaient statistiquement très significatifs (p<0.001). Plus la colonne vertébrale était longue, plus haute était située la terminaison de la moelle épinière.
  相似文献   
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