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排序方式: 共有1721条查询结果,搜索用时 15 毫秒
1.
G?khan Tun?bilek Serdar Nasir Omer Ozkan Aycan Kayik?io?lu Emin Mavili 《Nordisk plastikkirurgisk forening [and] Nordisk klubb for handkirurgi》2004,38(2):94-99
Defects in the sacrococcygeal and ischial soft tissues can be treated with gluteus maximus and posterior thigh V-Y advancement flaps. However, late complications include recurrence and dehiscence of the suture line. Increasing the amount of the soft tissues over the bony prominences and multilayered closure may have an advantage for long-term durability. We modified the V-Y advancement technique by de-epithelialising the medial parts of the flap and burying them under the opposing edge of the wound or the flap. Sixteen patients with various defects of the sacrococcygeal and ischial soft tissues were operated on using this technique. All the flaps healed well with no partial or complete loss of the flap. Three patients developed complications. The main advantage of our technique is the use of healthy tissues to obliterate the dead spaces under the edges of the wound or the opposing flap. In this way, not only the defect in the skin but the defect in the subcutaneous tissue, with its iceberg tip at the surface, is treated effectively. To have an additional layer of tissue between the bone and the superficial tissues provides an extra cushion of soft tissue and avoids putting the suture line directly over the bony prominences. We used this modification safely for both unilateral and bilateral flaps. It could also be used successfully in other parts of the body. 相似文献
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Nasir J 《Clinical genetics》2001,60(5):332-333
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Random minicircle DNA molecules were released from isolated kinetoplast network DNA of Trypanosoma congolense by BamHI digestion and cloned into plasmid pUC19. The sequences of two cloned minicircles (958 bp and 964 bp) were determined. Both minicircles contain the 13 bp sequence, 5'-GGGGTTGGTGTAA-3', thought to be the replication origin of minicircles in other trypanosomatids. The two minicircles have extensive homology in the 120 bp preceeding, and the 20 bp following, this 13-mer but only scattered homology elsewhere. Both possess tandem repeats downstream of the 13-mer. Comparison of these minicircles with minicircle sequences from other trypanosomatids reveals that they have the same general sequence organization as the others although only the 13-mer and its flanking regions are homologous. 相似文献
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The increasing prevalence of penicillin-resistant Streptococuus pneumoniae urges for fast and accurate susceptibility testing methods. This study evaluated the comparability of three commonly used techniques; disk diffusion, E-test and agar dilution, to detect penicillin susceptibility in clinical isolates of S. pneumoniae. Fifty pneumococcal isolates, obtained from patients at the University of Malaya Medical Centre, were selected to include both penicillin-susceptible strains and those that had decreased susceptibility (resistant and intermediate) to penicillin. The minimum inhibitory concentration (MIC) values of penicillin to serve as the reference was determined by the agar dilution method in which, based on the MIC breakpoints recommended by the National Committee for Clinical Laboratory Standards (NCCLS), 27 strains had decreased susceptibility to penicillin with 17 strains resistant and 10 intermediate. Comparing to the agar dilution method, oxacillin disk diffusion test detected all strains with decreased penicillin susceptibility as such while E-test showed a close agreement of susceptibility (92%) of the isolates to penicillin. This confirmed that oxacillin is a good screening test for S. pneumoniae isolates with decreased susceptibility to penicillin while E-test is very reliable for rapid and accurate detection of penicillin susceptibility. 相似文献
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Abdullahi Idris Nasir Lozano Carmen Juárez-Fernández Guillermo Höfle Ursula Simón Carmen Rueda Silvia Martínez Angela Álvarez-Martínez Sandra Eguizábal Paula Martínez-Cámara Beatriz Zarazaga Myriam Torres Carmen 《European journal of clinical microbiology & infectious diseases》2023,42(5):569-581
European Journal of Clinical Microbiology & Infectious Diseases - This study determined the carriage rates and antimicrobial resistance (AMR) genes of enterococci from... 相似文献
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Ruck NF Hafeez M Manzur S Nasir F Rivers K Prozesky D 《Journal of health & population in developing countries》1999,2(1):78-87
Pakistan's public sector is organized in a federal system with many management and planning functions devolved to the 4 provincial governments. Provincial health secretariats lead on most policy and planning decisions for health services. The provinces employ health personnel, although the national Public Service Commission controls some key aspects of human resources management. Reporting the findings of a training needs assessment (TNA) for health personnel in the provincial health services of Punjab, the authors show how TNA can be used systematically to improve the quality of health professional training. They also discuss the extent to which better training could contribute to improved health management capacity in Pakistan, and describe the context and problems of Pakistan's health services, focusing upon management capacity, and the methods and results of a training needs assessment conducted to address the problems. A final section covers the usefulness of the TNA method in Pakistan and its applicability to other countries. Moreover, the implications of decentralization and the problems of preparing training plans in the absence of decentralized structures are discussed. 相似文献
10.
Mohammed Najeeb Al-Hashem Muhammad Nasir Amin Ali Ajwad Muhammad Afzal Kaffayatullah Khan Muhammad Iftikhar Faraz Muhammad Ghulam Qadir Hayat Khan 《Materials》2022,15(22)
Due to the increasing prices of cement and its harmful effect on the environment, the use of cement has become highly unsustainable in concrete. There is a considerable need for promoting the use of cement replacement materials. This study investigates the effect of variable percentages of metakaolin (MK) on the mechanical and durability performance of concrete. Kaolin clay (KC) was used in the current research to prepare the MK by the calcination process; it was ground in a ball mill to its maximum achievable fineness value of 2550 m2/Kg. Four replacement levels of MK, i.e., 5%, 10%, 15%, and 20% by weight of cement, in addition to control samples, at a constant water-to-cement (w/c) ratio of 0.55 were used. For evaluating the mechanical and durability performance, 27 cubes (6 in. × 6 in. × 6 in.) and 6 cylinders (3.875 in. diameter, 2 in. height) were cast for each mix. These samples were tested for compressive strength under standard conditions and in an acidic environment, in addition to being subjected to water permeability, sorptivity, and water absorption tests. Chemical analysis revealed that MK could be used as pozzolana as per the American Society for Testing and Materials (ASTM C 618:2003). The results demonstrated an increased compressive strength of concrete owing to an increased percentage of MK in the mix with aging. In particular, the concrete having 20% MK after curing under standard conditions exhibited 33.43% higher compressive strength at 90 days as compared to similarly aged control concrete. However, with increasing MK, the workability of concrete decreased drastically. After being subjected to an acid attack (immersing concrete cubes in 2% sulfuric acid solution), the samples exhibited a significant decrease in compressive strength at 90 days in comparison to those without acid attack at the same age. The density of acid attack increased with increasing MK with a maximum corresponding to 5% MK concrete. The current findings suggest that the local MK has the potential to produce good-quality concrete in a normal environment. 相似文献