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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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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   
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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   
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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   
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Five commercially available nitropolyclyclic aromatic hydrocarbons (nitro-PAH), namely, 4-nitrobiphenyl, 2-nitrofluorene, 9-nitroanthracene, 1-nitropyrene, and 2,7-dinitrofluorene, were exposed under restricted sunlight in the open air. The direct-acting mutagenicities of the samples after an exposure of 45 days were measured in order to compare them with those of the original samples in the Ames Salmonella typhimurium bioassay. It was found that the mutagenicities of some nitro-PAH do not change significantly while the mutagenicities of others increase or decrease after exposure. A preliminary study of nitro-PAH reaction products after exposure using GC, GC/MS, and FT-IR is also reported.  相似文献   
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