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81.
金黄色葡萄球菌儿童株耐药性分析 总被引:2,自引:0,他引:2
目的 了解儿童中金黄色葡萄球菌所致疾病的分布及其对常用抗生素的敏感情况。方法 收集连续12个月的临床致病株,根据菌落形态、革兰染色特点和乳胶凝集实验对金黄色葡萄球菌进行初步筛选,用细菌自动鉴定系统Vitek GPI卡和GPS-101卡进行菌株鉴定和药敏试验。结果 分离到金黄色葡萄球菌145株,其中来自呼吸道感染患儿痰或咽拭子培养109株,占75.17%,来自血培养16株,占11.03%,来自脓液、阴道分泌物培养分别占6.21%和5.51%。药敏试验显示92.4l%的菌株产生β-内酰胺酶,96.55%的菌株对青霉素耐药,但耐苯唑西林的仅占6.21%。99.31%和100%的菌株分别对利福平和万古霉素敏感,对环丙沙星、阿莫西林/棒酸、头孢唑林、复方新诺明、庆大霉素和林可霉素的敏感率分别为95.86%、93.10%、92.41%、86.21%、84.83%和80.69%,37.93%的菌株对红霉素耐药。结论金黄色葡萄球菌常引起儿童呼吸道感染,对苯唑西林的耐药率低.该药仍是治疗小儿会黄色葡萄球菌感染的有效药物。 相似文献
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本文采用Griess试剂、间接免疫荧光法和同位素释放等方法,发现新城鸡瘟病毒Losota系(NDV-L)与人外周血粘附性单个核细胞(a-MCs)作用2~4h后,可稳定地吸附在a-PBMCs表面,并使其释放一氧化氮(NO),释放量与阳性对照组(BCG-LPS作用的a-PBMCs)相近;采用~3H-TdR释放法测定NDV-L作用的a-PBMCs对K_(562)靶细胞的细胞毒活性,发现具有明显的杀伤效应,且该杀伤效应与NO的产生有一定的依赖性。 相似文献
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86.
寒冷干燥地区平时火器伤的早期处理 总被引:3,自引:3,他引:0
目的 探讨寒冷干燥地区平时火器伤伤情特点与早期救治方法。方法 对 1991年 1月— 2 0 0 2年 12月间 40例火器伤病人的临床救治进行回顾分析。结果 2 4例枪伤中 ,2 0例一期缝合伤口 ,均一期愈合 ,另外 4例只清创未一期缝合的伤口 ,3例愈合 ,1例感染 ;4例骨折内固定均愈合良好 ,无骨髓炎发生。 16例炸伤病人局部软组织损伤及污染比枪弹伤重 ,14例一期缝合伤口中 ,10例一期愈合 ,4例感染 ,骨折内固定 2例 ,均愈合良好 ,无骨髓炎发生。结论 寒冷干燥地区火器伤早期伤道清创时限可适当延长 ,在平时火器伤的救治中 ,对软组织条件较好的创面 ,早期清创后可一期闭合伤口和骨折内固定 ,这样可减少感染和伤残 ,促进康复 相似文献
87.
Gresham T Richter Jacob E Smith Horace J Spencer Chun Y Fan Emre Vural 《Otolaryngology--head and neck surgery》2007,137(2):239-242
OBJECTIVES: Histological comparison of human-based (AlloDerm) and porcine-based (ENDURAGen) dermal matrices regarding tissue incorporation and neovascularization as potential soft tissue augmentation materials. STUDY DESIGN: In vivo, rat model. METHODS: Subcutaneous implantation of 1-mm thick, 1 cm x 1 cm pieces of AlloDerm, ENDURAGen, and meshed ENDURAGen was performed in 24 Sprague Dawley rats. Implant materials were harvested at 4 (n = 12) and 8 weeks (n = 12). Histological quantification of soft tissue ingrowth and microvascular density was performed following hematoxylin-eosin staining and CD34 immunohistochemistry, respectively. RESULTS: AlloDerm showed significantly greater soft tissue ingrowth and microvascular density compared with both ENDURAGen and meshed ENDURAGen at 4 and 8 weeks (P < 0.001). CONCLUSIONS: Although these results may differ in human host tissues, AlloDerm seems to be a more suitable dermal matrix implant than ENDURAGen for cases in which tissue incorporation and neovascularization are sought for the optimal outcome based on this animal model. 相似文献
88.
Anatomic and spiral computed tomographic study of the genial tubercles for genioglossus advancement.
Shan Kai Yin Hong Liang Yi Wen Ying Lu Jian Guan Hong Min Wu Zhen Yu Cao Dong Zhen Yu Yan Yan Huang Chun Gen Wu 《Otolaryngology--head and neck surgery》2007,136(4):632-637
OBJECTIVE: To measure and compare Chinese mandibular genial tubercles measured anatomically and with computed tomography (CT). STUDY DESIGN AND SETTING: Spiral CT scans were taken of 40 adult human skulls; the superior genial spines were measured using anatomic and CT methods. RESULTS: The height and width of the superior genial spines, mandible thickness, and distance from the menton to the inferior and superior margins of the superior genial spines were 5.82 +/- 0.71, 6.98 +/- 1.35, 11.95 +/- 1.59, 11.08 +/- 2.05, and 16.91 +/- 2.30 mm from anatomic measurements and 6.17 +/- 0.71, 7.01 +/- 1.13, 12.19 +/- 1.64, 10.41 +/- 1.55, and 15.73 +/- 2.12 mm using spiral CT, respectively. The anatomic and CT measurements were correlated. CONCLUSION: Spiral CT of the genial tubercles can help locate the osteotomy in genioglossus advancement. SIGNIFICANCE: This study acquired reference data on Chinese genial tubercles demonstrating that CT measurements of the genial tubercles reflect their anatomy, which should allow accurately locate the osteotomy. 相似文献
89.
Sulfaguanidine (Ⅰ) and sulfadimidine (Ⅱ) in infantile co-sulfadimidine powders were determined using derivative-spectrophotometry. Ⅰ and Ⅱ were extracted with 10 ml dilute HCl, and added 0.1 mol/L HC1 to 100 ml. Ⅰ was analyzed with spectrophotometry at 220 nm. Ⅱ was analyzed with derivative-spectrophotometry at 321, 324 nm. Recoveries of Ⅰ and Ⅱ were 100.2±0.33% and 100.3±0.55% respectivly. 相似文献
90.
Ion channel expression by white matter glia: I. Type 2 astrocytes and oligodendrocytes 总被引:12,自引:0,他引:12
White matter is a compact structure consisting primarily of neuronal axons and glial cells. As in other parts of the nervous system, the function of glial cells in white matter is poorly understood. We have explored the electrophysiological properties of two types of glial cells found predominantly in white matter: type 2 astrocytes and oligodendrocytes. Whole-cells and single-channel patch-clamp techniques were used to study these cell types in postnatal rat optic nerve cultures prepared according to the procedures of Raff et al. (Nature, 303:390-396, 1983b). Type 2 astrocytes in culture exhibit a "neuronal" channel phenotype, expressing at least six distinct ion channel types. With whole-cell recording we observed three inward currents: a voltage-sensitive sodium current qualitatively similar to that found in neurons and both transient and sustained calcium currents. In addition, type 2 astrocytes had two components of outward current: a delayed potassium current which activated at 0 mV and an inactivating calcium-dependent potassium current which activated at -30 mV. Type 2 astrocytes in culture could be induced to fire single regenerative potentials in response to injections of depolarizing current. Single-channel recording demonstrated the presence of an outwardly rectifying chloride channel in both type 2 astrocytes and oligodendrocytes, but this channel could only be observed in excised patches. Oligodendrocytes expressed only one other current: an inwardly rectifying potassium current that is mediated by 30- and 120-pS channels. Because these channels preferentially conduct potassium from outside to inside the cell, and because they are open at the resting potential of the cell, they would be appropriate for removing potassium from the extracellular space; thus it is proposed that oligodendrocytes, besides myelinating axons, play an important role in potassium regulation in white matter. The conductances present in oligodendrocytes suggest a "modulated Boyle and Conway mechanism" of potassium accumulation. 相似文献