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Acinetobacter baumannii has emerged as a serious cause of nosocomial infections. Rapid identification of this pathogen is required so that appropriate therapy can be given and outbreaks controlled. This study evaluated a multiplex PCR and an automated ribotyping system for the rapid identification of Acinetobacter baumannii. In total, 22 different reference strains and 138 clinical isolates of Acinetobacter spp., identified by 16S-23S rRNA intergenic spacer (ITS) sequence analysis, were evaluated. All A. baumannii isolates (82 clinical isolates and one reference strain) were identified by the multiplex PCR method (specificity 100%). The sensitivity and specificity of the ribotyping system for identification of A. baumannii were 85.5% (71/83) and 93.5% (72/77), respectively. An additional 100 clinical isolates belonging to the Acinetobacter calcoaceticus-A. baumannii complex were used to compare these two methods for identification of A. baumannii, and this comparison revealed a level of disagreement of 14% (14 isolates). The accuracy of the multiplex PCR was 100%, which was confirmed by sequence analysis of the ITS and recA gene of these isolates. Thus, the multiplex PCR method dramatically increased the efficiency and speed of A. baumannii identification.  相似文献   
33.
[目的]初步建立一个临床常见病原菌的标准PCR-CE-RFLP数据库,为临床快速鉴定病原菌奠定基础。[方法]选取临床分离的病原菌共167株,筛选16S rRNA基因和16S-23S rRNA间区基因的合适引物,分别用FAM和JOE两种荧光素标记,调整PCR反应条件,让两种引物能同时在同一条件下反应,所得产物先用普通琼脂糖凝胶电泳,再分别用限制性内切酶HaeIII进行不完全酶切,酶切产物50倍稀释后进行毛细管电泳(PCR-CE-RFLP),测定酶切片段长度差异。[结果]针对16S rRNA基因的RFLP谱数据只能将病原菌鉴定到"科"的程度,而单纯应用16S-23S rRNA间区基因的RFLP谱数据虽能区分绝大多数细菌,但个别种属内仍然出现相似的谱型。经过双位点PCR-CE-RFLP分析后,则可将所有细菌鉴定到"种"的程度。[结论]利用16S rRNA基因和16S-23S rRNA间区基因PCR-CE-RFLP进行细菌鉴定简便快捷,能将传统方法需要十几个小时甚至几十小时的鉴定工作缩短到几个小时,是一种极有临床应用价值的快速诊断方法。  相似文献   
34.
Detailed knowledge concerning the action of extracorporeal shock waves on the locomotor system as well as concerning possible side effects of extracorporeal shock wave therapy (ESWT) are crucial to optimize the clinical use of ESWT for the treatment of illnesses such as calcific tendinitis of the shoulder, tennis elbow, plantar fasciitis, aseptic pseudarthrosis, and aseptic hip necrosis. This study presents the current knowledge gained from animal experiments, which have yielded important findings, in particular concerning possible side effects of ESWT. Very recent studies have also provided valuable insights into the molecular actions of extracorporeal shock waves on the locomotor system. Further intensified experimental animal research will greatly improve the scientific basis for the clinical use of ESWT in the near future.  相似文献   
35.
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Metered dose inhaler (MDI) with spacer is the preferred method for administration of aerosolized medications in pediatric asthma. The expense of commercial spacers limits their use and indigenous alternatives have therefore been developed. Information on the clinical efficacy of home-made spacers is limited. This study was conducted to compare the efficacy of a valve-less home-made spacer with a commercial spacer in delivering salbutamolvia MDI in acute asthma. Asthmatic children aged 5–15 years who presented with an acute exacerbation to the pediatric chest clinic of a tertiary care hospital were enrolled in a single blinded randomized parallel group study. The study patients received 10 puffs of salbutamol (100(igJ puff)via MDI-home-made spacer or MDI-commercial spacer. Pre and post inhalation measurements of peak expiratory flow rate (PEFR), oxygen saturation (SaO2), respiratory rate (RR), pulse rate (PR) were made and compared. Sixty children were enrolled in the study, 31 were administered salbutamolvia the home-made spacer and 29via the commercial spacer. The median increase in PEFR was similar in both the groups (20.8% vs22.2%, p=0.4), clinical improvement being satisfactory in all patients. The valve-less home-made spacer is equally efficacious and cheaper than the commercial spacer in administering bronchodilators in acute exacerbations of asthma. Further studies on the efficacy of home-made spacer in delivery of inhaled steroids are needed.  相似文献   
37.
目的:构建地乌药材基原物种系统鉴定体系,并对全国16个产地的地乌药材进行综合品质评价,为地乌药材产地选择及临床用药安全奠定基础。方法:使用传统鉴别方法结合DNA条形码核糖体DNA第二内部转录间隔区(ITS2)序列分子鉴定技术快速鉴别地乌药材真伪,并基于HPLC-UV对地乌药材中5个有效成分进行含量测定,采用Welch Ultimate XB-C18色谱柱(4.6 mm×250 mm,5μm),流动相乙腈-0.01%三氟乙酸溶液(30∶70),检测波长210 nm,柱温30℃,流速1.0 mL·min-1。结果:传统鉴别及DNA条形码快速鉴别技术均能准确鉴别地乌药材真伪。BLAST比对分析发现,16个产地地乌药材均与林荫银莲花Anemone flaccida具有最大相似度;基于多指标成分含量测定表明湖北恩施板桥镇的地乌药材中5个三萜皂苷类成分含量之和最高(10.59%),其次为贵州毕节赫章(6.28%)和湖北长阳都镇湾(5.64%)。结论:DNA条形码技术可作为地乌药材传统鉴定技术的有效补充,该鉴别体系可保障地乌药材基原准确及临床用药安全。HPLC多指标成分综合评价及聚类分析结果表明在本研究所涉及的产地中,湖北恩施、长阳、五峰,贵州毕节和重庆金佛山的地乌药材质量较优,可作为地乌药材的重要产地。  相似文献   
38.
Open, Double-Blind and Long-Term Study of Vigabatrin in Chronic Epilepsy   总被引:1,自引:4,他引:1  
We performed an open, double-blind, and long-term study of vigabatrin (gamma-vinyl-GABA, GVG) in patients with treatment-resistant epilepsy who were receiving only one or at most two standard antiepileptic drugs (AEDs). The novel design included a parallel, double-blind, placebo-controlled phase that minimized the number of patients receiving placebo and allowed determination of the optimum dose of GVG for each patient before initiation of the double-blind phase. The study was divided into four phases. The first phase was a 6-week period of baseline observation. In the second phase, GVG was added openly to previous AEDs for 8 weeks. During the first 2 weeks of this phase, the dose of GVG was increased weekly and then, in the absence of adverse effects, was held constant for the next 6 weeks. At the end of this open phase, seizure frequency during the 6 weeks of constant treatment was compared with the baseline seizure frequency for each patient. Patients who experienced reduction greater than 50% in the frequency of any seizure type during the open phase were defined as responders. These responders were then entered into the third and double-blind phase, in which they were randomly allocated wither to continue active GVG treatment or placebo for 8 weeks. Thirty-three patients entered the study; 31 of 33 patients completed the initial open phase. Twenty patients achieved a reduction greater than or equal to 50% in the frequency of one or more seizure types and were eligible for the double-blind phase; 10 were randomized to continue GVG and 10 were randomized to placebo.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
39.
During around five millions years our ancestors, who were arboreal primates, became progressively occasional, frequent and permanent terrestrial bipeds. Thus, they restricted their locomotor repertoire from polyvalence to specialization. We show that the adaptation to bipedalism is the result of two different processes, the result of natural selection and the result of learning to walk. The characters of our skeleton, heritage of natural selection, affected first pelvis and vertebral column and then cranial base, body proportions and feet. Since reaching bipedal balance is a very demanding constraint in the face of gravity, we describe the “epigenetic” characters which develop in association with learning to walk. Important femoral angular modifications result in the adduction of lower limbs. The angle of pelvic incidence, which defines the sagittal pelvic morphology, increases with gait acquisition in tight association with the formation of lumbar curvature. A link can be established between these genetic modifications and these epigenetic acquisitions. As an illustration we show how the pelvis and spine became a functional unit during the transition from facultative to permanent bipedalism, probably during the evolution of the large group of Homo erectus.  相似文献   
40.
Background contextSome postoperative complications after anterior cervical fusions have been attributed to anterior cervical plate (ACP) profiles and the necessary wide operative exposure for their insertion. Consequently, low-profile stand-alone interbody spacers with integrated screws (SIS) have been developed. Although SIS constructs have demonstrated similar biomechanical stability to the ACP in single-level fusions, their role as a stand-alone device in multilevel reconstructions has not been thoroughly evaluated.PurposeTo evaluate the acute segmental stability afforded by an SIS device compared with the traditional ACP in the setting of a multilevel cervical arthrodesis.Study designIn vitro human cadaveric biomechanical analysis.MethodsThirteen human cadaveric cervical spines (C2–T1) were nondestructively tested with a custom 6 df spine simulator under axial rotation, flexion-extension, and lateral bending loading. After intact analysis, eight single-levels (C4–C5/C6–C7) from four specimens were instrumented and tested with ACP and SIS. Nine specimens were tested with C5–C7 SIS, C5–C7 ACP, C4–C7 ACP, C4–C7 ACP+posterior fixation, C4–C7 SIS, and C4–C7 SIS+posterior fixation. Testing order was randomized with each additional level instrumented. Full range of motion (ROM) data were obtained and analyzed by each loading modality, using mean comparisons with repeated measures analysis of variance. Paired t tests were used for post hoc analysis with Sidak correction for multiple comparisons.ResultsNo significant difference in ROM was noted between the ACP and SIS for single-level fixation (p>.05). For multisegment reconstructions (two and three levels), the ACP proved superior to SIS and intact condition, with significantly lower ROM in all planes (p<.05). When either the three-level SIS or ACP constructs were supplemented with posterior lateral mass fixation, there was a greater than 80% reduction in ROM under all testing modalities (p<.05), with no significant difference between the ACP and SIS constructs (p>.05).ConclusionsThe SIS device may be a reasonable option as a stand-alone device for single-level fixation. However, SIS devices should be used with careful consideration in the setting of multilevel cervical fusion. However, when supplemented with posterior fixation, SIS devices are a sound biomechanical alternative to ACP for multilevel fusion constructs.  相似文献   
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