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71.
A soleus flap as a local reconstructive option for soft-tissue coverage of a tibial wound in the distal third of the leg has never been well recognized. In a 2-year period, seven patients underwent reconstruction of a less extensive tibial wound (4 × 3 to 10 × 4 cm) in the distal third of the leg after orthopedic trauma with the laterally extended medial hemisoleus flap. The flap was elevated with emphasis on the preservation of the most distal perforators from the posterior tibial vessels to the flap as possible while allowing adequate rotation of the flap to cover the exposed tibia and/or hardware and on the possible preservation of foot planter flexion by reconstruction of the proximal Achilles’ tendon. In this series, there was no total or partial flap loss. All patients healed their tibial wounds primarily with reliable soft-tissue coverage, evidenced fracture healing, and good cosmetic outcome during follow-up. Thus, the laterally extended medial hemisoleus flap described by the author can be a reliable option for soft-tissue coverage of a less extensive tibial wound in the distal third of the leg. It offers a more cost-effective approach for managing this unique problem and can be performed by most reconstructive surgeons without microsurgical expertise.  相似文献   
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73.
Abstract— NdYAG laser-induced modification of the root surface may inhibit development of external inflammatory resorption in replanted teeth. This study tested this hypothesis in vivo. The pulp chambers of six mandibular premolars in each of two dogs were accessed, inoculated with plaque, and sealed (Groups 1, 2). Two additional premolars in each dog were endodontically treated without inoculation (Groups 3, 4). After 2 weeks, teeth were hemisected and extracted. Each root had a 2times3 mm surface area denuded of cementum on the buccal and lingual surface. In Groups 1 (n= 12 roots) and 3 (n=4), the denuded surfaces were wiped with 15% EDTA, coated with black ink, and irradiated with Nd:YAG laser (0.75 W, 15 ppc, 300 pm tip, 20 s). In Groups 2 (n= 12) and 4 (n= 4), the surfaces were wiped with 15% EDTA, and rinsed with sterile saline for 20 s. Roots were replanted within 5 min. The dogs were perfwion-euthanised 10 weeks after replantation. Block specimens were removed, decalcified, embedded and horizontally sectioned (6 pm) at 180-pm intervals, resulting in 10 to 14 cross-sections of each root. From these, the middle five consecutive sections were stained with hematoxylin and eosin, and observed by light microscopy for occurrence of surface, inflammatory and replacement resorption on the denuded surfaces. No obvious differences were noted between the laser-irradiated and non-irradiated surfaces. Inflammatory resorption was frequent in Groups 1 and 2, and absent in Groups 3 and 4. Replacement resorption was minimal in Groups 1 and 2, and frequent in Groups 3 and 4. Differences between Groups 1 and 2, and between Groups 3 and 4 were not significant, whereas the differences between the two pairs of groups were statistically significant (chi-square and two-way ANOVA, P>0.006). These results did not support the hypothesis, and questioned the clinical validity of the surface modification in NdYAG laser-irradiated den-tin. Therefore, the clinical application of NdYAG laser to the root surfaces of replanted teeth is not warranted.  相似文献   
74.
双头加压螺纹钉贴股骨距内固定治疗股骨颈骨折   总被引:8,自引:0,他引:8  
在X光电视下采用双头加压螺纹钉贴股骨距内固定治疗新鲜股骨颈骨折42例,随访平均2.5年,其中16例随访3年以上,骨折愈合率95.2%,骨折不愈合并股骨头缺血性坏死率4.76%。认为加压螺纹钉贴股骨距内固定可使钉的受力由较大剪应力变为较大轴向力承受,减少骨折处的剪应力,并加压于骨折端能促进骨折愈合。具有操作简单、进钉准确、创伤小、固定牢靠、并发症少等优点。  相似文献   
75.
Observations on time-dependent localization of tetra(3-hydroxyphenyl)porphin (3-THPP) in human malignant melanoma transplanted to athymic nude mice from 1 to 120 h after intraperitoneal (i.p.) 10 mg kg–1 b.w. administration were made by means of fluorescence microscopy. Fluorescence was found on the membrane of the melanoma cells and in the cytoplasm with a peak fluorescence intensity at 24 h post-injection of 3-THPP. The growth of the tumour cells was obviously inhibited at an early stage after PCT. Morphological changes of the tumour at various intervals after treatment by PCT with 3-THPP were also observed. Diffuse degeneration of the tumour cells with swelling of mitochondria and endoplasmic reticulum, heterochromatin aggregation and margination, etc., and subsequently diffuse necrosis with little or no the background of tumorous vascular response were found at an early stage after PCT. On the other hand, it was also observed that the necrosis of the melanoma areas was caused as a consequence of tumorous vascular injury at a later stage after PCT. Thus, two tumoricidal processes caused by PCT with 3-THPP were seen: a direct phototoxic action on tumour cells at an early stage after PCT and an indirect effect secondary to tumorous vascular injury at a later period after PCT.  相似文献   
76.
Poverty, health services, and health status in rural America   总被引:5,自引:0,他引:5  
Access to health services for everyone has been a major policy goal in the United States: inequitable access is assumed to lead to inequitable health status, particularly for low-income groups. A sophisticated model of the relation between poverty, health care needs, service use, and health outcomes is used to analyze cross-sectional data on 7,823 adults from 36 rural communities. Improved access and use are helpful, but evidence clearly indicates that combined health and social initiatives will be necessary to reduce inequalities in health status.  相似文献   
77.
用AR CM MIC阳离子测定系统,测量单个细胞内游离钙浓度([Ca2+]i),研究8-(N,N-二乙胺)-n-辛基 3,4,5-三甲氧基苯甲酸酯(TMB-8)对培养乳牛基底动脉平滑肌[Ca2+]i的作用。在细胞外钙浓度为1.3mmol·L-1时,TMB-8(30μmol·L-1)可明显抑制BHQ,NE及KCl引起[Ca2+]i的升高。在细胞外钙为零+EGTA 0.1mmol·L-1时,TMB-8(10,30及100μmol·L-1)可浓度依赖性地降低静息[Ca2+]i,TMB-8(30μmol·L-1)可几乎完全阻断BHQ及NE引起[Ca2+]i的增加。研究表明TMB-8降低培养乳牛基底动脉平滑肌[Ca2+]i的机制,主要是抑制肌浆网Ca2+的释放,或增加肌浆网对Ca2+的摄入,并由此间接地抑制细胞外钙的内流。  相似文献   
78.
A novel cardiokymograph system is introduced. The new system features a capacitance transducer with increased sensitivity and can be used in multichannel measurements. The novelty of this technique is the injection of a current into the patient coupled with the use of a capacitive displacement transducer and the possibility of multichannel monitoring. It provides for the possibility of removing breath noise when some signal processing technique, such as adaptive filtering, is used. Further investigation is needed to demonstrate clinical significance and pathologies.  相似文献   
79.
80.
麦冬类中药组织切片计算机三维重建图鉴   总被引:9,自引:0,他引:9  
利用计算机技术实现麦冬类中药组织连续切片三维重建与动态显示,为计算机辅助生药学鉴定和教学提供了新的三维图像技术和研究资料。  相似文献   
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