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101.
102.
目的研究载体对固体室温空间驱避剂的挥发度、成形性、稳定性、残余量、驱蚊率及工艺的影响。方法比较7种不同载体的固体室温空间驱避剂的挥发速率、成形性、残余量、稳定性、驱蚊率及工艺,最终确定合适的载体。结果 7种固体室温空间驱避剂的挥发趋势大体相同,挥发速度有所差别,成形性各有差异,稳定性基本没有出现异常,残余量各自不同,驱蚊率皆在80%以上,制作工艺各有差异。结论琼脂的成形性最好,表面平整光滑,硬度最大,生产灌装工艺简单,驱蚊率在90%以上,稳定性未出现异常。最后确定选用琼脂作为固体室温空间驱避剂的载体。  相似文献   
103.
Various bone proteins and growth factors in specific concentrations are required for bone formation. If the body cannot produce sufficient quantities of these factors, bone trauma can be healed with an implant that includes the required factors in a carrier. This study was designed to evaluate various calcium salt candidates that can be used as carrier with reindeer bone protein extract to induce ectopic bone formation in the muscle pouch model of mouse. The bone protein extract was either impregnated into the disc form of carrier or mixed with carrier powder before implantation. The radiographic analysis indicated increased bone formation in all of the active groups containing the bone protein extract compared to the controls within 21 days follow-up. The highest bone formation was seen in the group with calcium sulfate with stearic acid where new bone and calcified cartilage were clearly visible. The greatest bone formation occurred in the groups that had bone protein extract readily available. This indicates that the bone forming factors in sufficient concentrations are required at the early stage of bone formation. The calcium sulfate with stearic acid was the most suitable and effective carrier for reindeer bone protein extract.  相似文献   
104.
目的分析老年肺部感染患者病原菌分布特点及耐药性,旨在为临床合理用药提供参考依据。方法对2011年12月-2012年12月158例老年肺部感染患者的痰标本进行细菌培养、鉴定、药物敏感试验,试验菌株均采用全自动微生物鉴定分析仪进行鉴定,药敏试验采用纸片扩散法(K-B),数据采用SPSS16.0统计软件进行分析。结果 158例老年肺部感染患者的痰标本检出144株病原菌,其中革兰阴性菌102株占70.83%,革兰阳性菌40株占27.78%,真菌2株占1.39%;革兰阴性杆菌对亚胺培南/西司他丁耐药率最低为1.96%,其次为美罗培南、哌拉西林/他唑巴坦,耐药率分别为3.92%、13.73%,革兰阳性球菌对青霉素G、红霉素、氧氟沙星的耐药率较高,分别为87.50%、80.00%、77.50%。结论及时了解病原菌的分布及耐药趋势有利于合理选择抗菌药物,制定有效治疗方案,不仅可降低老年患者感染的发生及病死率,而且能够减少耐药菌株的产生。  相似文献   
105.
106.
The mitochondrial phosphate carrier gene (PiC) encodes a membrane protein that mediates the supply of inorganic phosphate from the cytosol into the mitochondrial matrix. This substrate‐specific transport system plays an important role in efficient ATP synthesis. Mammals appear to have only one PiC with two alternative splicing variants whose functional differences remain unclear. The present study is the first to characterize the multiple genes that encode PiC in insects. Bombyx mori was found to have two PiC paralogues, one ubiquitous and one testis‐specific, the latter seeming to be present only in Lepidoptera. Drosophila melanogaster was found to harbour two PiC paralogues, whereas Liriomyza chinensis, another dipteran, has three PiC paralogues. Two PiCs were found to be present in Plautia stali, and silencing either of these genes affected the normal development of P. stali nymphs, although their expression patterns differed amongst tissues. Schistocerca gregaria and Locusta migratoria have two PiC each, with different expression patterns. Tribolium castaneum was found to have only one PiC, which appears to play an essential role in larval development. Thus, although the inorganic phosphate transport system appears to be conserved across eukaryotes, PiC has become specialized in the different tissues of different insect species.  相似文献   
107.
BackgroundFemale carriers of Duchenne muscular dystrophy (DMD), although usually asymptomatic, develop muscle weakness up to 17% of the time, and a third present cardiac abnormalities or cognitive impairment. Clinical features of DMD carriers during childhood are poorly known.PatientsWe describe a cohort of pediatric DMD carriers, providing clinical, genetic, and histopathologic features, with a mean follow-up of 7 years.ResultsFifteen females with a DMD mutation (age range 5 to 18 years) were included. Seven patients (46%) presented with clinically evident symptoms and signs such as limb girdle weakness, abnormal gait, and exercise intolerance. The other eight patients (53%) were evaluated because of an incidental finding of elevated level of creatine kinase. Creatine kinase level was elevated in all, ranging from 392 to 13,000 U/L. Calf hypertrophy was observed in eight patients (53%). No patient developed respiratory or cardiac involvement. The most frequent complication was scoliosis (46%). Four patients (29%) also presented minor learning disabilities or behavioral problems. We performed electromyography in half of patients, showing myopathic pattern in four (53%). Muscle biopsy revealed a mosaic reduction of dystrophin in nine available cases. DMD gene mutations were mostly deletions (71%), resulting in loss of reading frame in five patients (36%). The three patients who experienced the most severe disease course were affected either by a nonsense or frameshift mutation.ConclusionsOur analysis suggests that DMD gene mutations may be suspected in a female child with persistently elevated levels of creatine kinase. Evidence of scoliosis, calf hypertrophy, or myopathic pattern at electromyography may also be helpful, and muscle biopsy is always indicative. DMD carriers should be followed for subtle orthopedic and psychiatric complications during childhood.  相似文献   
108.
Summary

Planar lipid membranes in the presence of the ion carriers valinomycin or nonactin were irradiated with 14 MeV electrons from a linear accelerator. A large increase of the membrane conductance by up to more than two orders of magnitude was found. The effect is virtually abolished either at high pH, or in the absence of oxygen, or in the presence of the radical scavenger ethanol. A further prerequisite for the effect is the presence of unsaturated fatty acid residues. A kinetic analysis of the carrier transport model based on current-voltage curves and on voltage-jump relaxation experiments was performed as a function of radiation dose. Only the translocation rate constant, kMS, of the charged carrier-ion complex was found to be influenced by irradiation. The effect is interpreted as an increase of the polarity (dielectric constant) of the membrane interior induced by the presence of polar products of lipid peroxidation. A combined action of OH- and HO2-radicals seems to be responsible for the phenomena. At large radiation doses (? 103 Gy) a reduction of the membrane conductance was observed. This is interpreted as an increased microviscosity, possibly caused by cross-linking of fatty acid residues. Ion carriers represent sensitive probes of radiation induced membrane damage.  相似文献   
109.
目的 研究医院呼吸重症监护病房(RICU)慢性阻塞性肺疾病急性加重期(AECOPD)下呼吸道病原菌分布及耐药性,探讨机械通气与非机械通气AECOPD下呼吸道病原菌分布的差异.方法 收集医院RICU收治AECOPD患者的痰标本,对微生物病原学分离、鉴定和药物敏感试验结果进行分析.结果 病原菌以革兰阴性菌为主,占71.77%,革兰阳性菌占11.76%,真菌占16.47%;亚胺培南、头孢哌酮/舒巴坦、哌拉西林/他唑巴坦及阿米卡星对革兰阴性菌的耐药率较低,产ESBLs肺炎克雷伯菌和大肠埃希菌检出率分别为28.57%和65.38%,差异有统计学意义(P<0.01),嗜麦芽寡养单胞菌对磺胺甲噁唑/甲氧苄啶、环丙沙星及头孢哌酮/舒巴坦保持高敏感性,未发现耐利奈唑胺、万古霉素及替考拉宁MRSA及MRCNS,机械通气的AECOPD患者的MASA感染率和混合培养比例显著高于未机械通气的患者(P<0.01).绪论 RICU的AECOPD患者感染以假单胞菌属、不动杆菌属及肠杆菌科为主,病原菌耐药率高,应重视病原学检查.  相似文献   
110.
目的 调查骨与关节化脓性感染的病原菌分布及耐药性,为临床抗菌药物治疗提供依据.方法 分析2010年1月-2011年11月骨科收治的272例骨与关节化脓性感染病例分离的病原菌及药敏试验结果.结果 表皮葡萄球菌、大肠埃希菌、金黄色葡萄球菌、鲍氏不动杆菌和铜绿假单胞菌分别占21.8%、16.4%、13.7%、12.2%及11.6%;骨科ICU共出现12株极端严重耐药菌,鲍氏不动杆菌和铜绿假单胞菌各6株;加强手卫生和环境清洁后未出现极端严重耐药菌.结论 葡萄球菌属是骨与关节化脓性感染的主要致病菌,抗菌药物使用前应常规进行血培养检查;早期感染以革兰阳性球菌为主,住院时间>2周出现鲍氏不动杆菌和铜绿假单胞菌感染,应严格手卫生,预防多药耐药菌感染.  相似文献   
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