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91.
The relationship was examined between the height and slope of the cervical zygapophyseal joints and the patterns of motion of the cervical vertebrae. The height and orientation of the C3---C7 superior articular processes were measured in lateral radiographs of 40 normal subjects. The C4-C6 facets were oriented at approximately 40° to the vertical, while the C3 and C7 facets were more steeply oriented. The heights of the superior articular processes were found to increase at progressively lower vertebral levels. Contrary to published views, the slope of the superior articular facets has no bearing on the pattern of motion of the cervical vertebrae. No relationship was found between slope of the facets and the location of the instantaneous axes of rotation of the cervical vertebrae. In contrast the height of the articular processes was perfectly related to the location of the axes of rotation. Articular height, but not slope, is a major determinant of the patterns of motions of the cervical vertebrae.

This study provides data necessary to confirm or deny the putative roles of the cervical zygapophyseal joints in determining motion of the cervical spine in the sagittal plane.  相似文献   

92.
Several unilateral external fixators were laboratory tested under applied axial, bending, and torsional loads. In certain cases the shear movement at the fracture site was substantial, up to 4 mm, and in all cases it was as significant as axial displacement. Also, under average full weight bearing, all the fixator/bone screw frameworks will allow too much axial movement at the fracture. This could inhibit healing and cause peak bone and screw stresses to approach yield.  相似文献   
93.
目的 研究桥本甲状腺炎(HT)合并甲状腺乳头状癌(PTC)患者的临床特征,并探讨外科治疗方案.方法 回顾性分析2009年1月至2010年12月间收治的首次手术的PTC患者资料128例,其中30例为HT合并PTC.结果 女性HT合并PTC发病率为男性的6.5倍.HT合并PTC中央组淋巴结转移率(46.7%)略高于单纯PTC者(39.4%).HT合并微小PTC的中央组淋巴结转移率(45.5%)明显高于单纯微小PTC者(16.7%).直径>1 cm的单纯PTC中央组淋巴结转移率(47.2%)明显高于单纯微小PTC者(16.7%).而多灶PTC的中央组淋巴结转移率(73.3%)明显高于单灶癌者(36%);HT合并多灶PTC的中央组淋巴结转移率(100%)明显高于单纯多灶PTC者(69.2%).结论 HT合并PTC多见于中年女性,易早期发生中央组淋巴结转移.全甲状腺切除并中央组淋巴结清扫是必要的治疗方法.  相似文献   
94.
Objective. To examine whether the type of unilateral external fixator significantly influences the stability of a tibial fracture.

Design. Inter-fragmentary displacements were measured during walking while the fractures were stabilized, first with one type of fixator then with another.

Background. It is commonly claimed that one type of fixator exerts a different influence on mechanical stability at a fracture in comparison with another.

Methods. This study compares inter-fragmentary displacement, fixator displacement and weight bearing during walking, in four patients stabilized with an Orthofix DAF, which was replaced by a Howmedica International Monotube.

Results. The null hypothesis of no difference in fixator performance was unproved (P < 0.05) through insufficient data. Inter-patient variability in inter-fragmentary displacement implies that anthropometry, gait and fracture type may influence fracture stability more than the type of fixator.

Conclusions. Since weight-bearing and displacements were not substantially different, no basis was found for the claim that one fixator provides a mechanical environment substantially different to another. Sample size was not large enough to prove that a small but statistically significant difference exists.  相似文献   

95.
96.
目的探讨经口内镜下肌切开术(POEM)治疗儿童贲门失弛缓症(AC)的临床疗效及并发症发生情况。方法回顾性分析该院2012年11月-2016年11月确诊AC并接受POEM治疗的17例患儿的临床表现、POEM手术过程及术后随访情况。结果 17例患儿均成功完成POEM,无严重并发症发生,手术时间(62.65±35.54)min;17例患儿术后随访12~36个月,手术前后AC临床症状评分(Eckardt评分)分别为5(4.0-6.0)和0(0.0-1.0)分,差异有统计学意义(P=0.000),临床症状明显缓解,体重减轻情况明显改善。结论 POEM治疗儿童AC安全性高,短期疗效确切,长期疗效及远期并发症有待大样本量的随访监测。  相似文献   
97.
The localisation of arteries or veins is facilitated by the use of an ultrasonic Doppler unit.* When a beam emitted by a detector transducer impinges on a blood vessel, an audible “flow” signal characteristic for an artery or a vein is produced. Since both the localisation of the blood vessel and the direction of puncture can be established with this unit, the method proves to be particularly useful in the search for vessels difficult to locate such as the subclavian vein. In 48 out of 50 cases the ultrasound assisted puncture of the subclavian vein and the placement of a venous catheter were successful. Such dangerous complications as haemorrhages and pneumothorax did not develop. The possibility of ultrasonic blood vessel localisation suggests itself also for the puncture of other veins and arteries provided they are not deeper than 4 cm below the skin.  相似文献   
98.
Different configurations of the Monticelli-Spinelli and Ilizarov external fixation systems were tested to define their mechanical properties. In five configurations the external fixator consisted of rings with tensioned wires (circular), while in one configuration two pairs of the tensioned wires and their correspondent ring were replaced by threaded pins (hybrid). Testing was performed in axial compression, bending and torsion. The results were compared to the characteristics of a selected linear fixator group. Both the circular and the hybrid configurations were non-linear in compression. In bending, circular fixators had a similar pattern in both anteroposterior and oblique loading directions. The bending load-displacement pattern for the hybrid fixators was similar to the linear fixators, higher stiffness in the plane of the pins. Torsion was linear for both circular and hybrid fixators, as for the linear fixators. By combination of wires and pins (hybrid configuration), the mechanical behaviour had characteristics from both linear and circular fixators. It is concluded that the three studied groups own different mechanical performance and can be considered as different types of fixators. While it has been demonstrated that osteogenesis can be achieved independently of the mechanical behaviour of the fixator, this study supports the suggestion that some complications can be related to the mechanical behaviour of the fixator.  相似文献   
99.
目的探讨全覆膜金属可回收支架治疗食管顽固性良性狭窄的安全性及疗效。方法回顾性分析行全覆膜金属可回收支架治疗的33例食管顽固性良性狭窄患者的临床资料,评价治疗的可行性、安全性及疗效。结果 33例患者共计放置可回收支架41支,其中8例患者行二次可回收支架置入,术后均有不同程度胸痛及异物感;术后并发支架移位11例(共计14支),移位发生率34.1%(14/41);其余22例患者(共计27支支架)均于术后4~8周顺利回收。术中及术后无明显出血、穿孔等并发症发生,无支架相关死亡病例。所有患者定期参加随访(12个月),其中12例成功解除梗阻,临床缓解率为36.4%(12/33)。结论全覆膜金属可回收支架用于治疗食管顽固性良性狭窄是安全可靠的,可使部分患者成功解除梗阻,但支架移位发生率高,有待于临床进一步研究解决。  相似文献   
100.
Because T-cell responses are critical for defense against viral infections, the synthetic P18 peptide (RIQRGPGRAFVTIGK) and active component of gp160 protein has previously been shown to induce cytotoxic and helper T-lymphocyte responses. In order to further define the T-helper cells, responses which are known to play a role in enhancing the immunological response to foreign antigen, we studied the response of individuals immunized with HIV gp160 candidate vaccines. We investigated the proliferative cellular response of peripheral blood mononuclear cells (PBMC) derived from individuals immunized with gp160 antigens in three different protocols. We found a PBMC proliferative response to synthetic P18 peptide in healthy immunized individuals induced by gp160 antigen with or without vaccinia virus. There was correlation between the proliferative response to P18 peptide and other antigens such as HIV-like proteins and gp160 molecule. HLA-DR typing revealed the possible presentation of P18 peptide by several different class II molecules. Since these class II molecules occur frequently in the general population, P18 peptide appears to contain broadly reactive epitopes and thus is presented by mutiple HLA class II molecules. Due to its broad reactivity P18 peptide is one of the candidates for inclusion as a subunit vaccine against HIV-1.  相似文献   
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