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41.
The in vitro activities of six commonly used antibiotics and six newer β-lactam agents were determined in 50 consecutive clinical isolates of β-lactamase-negative Neisseria gonorrhoeae. The gonococci isolated were notably resistant to penicillin, ampicillin, erythromycin, and tetracycline, whereas all of the strains were susceptible to the newer β-lactam agents cefoxitin and spectinomycin.  相似文献   
42.
目的:在心肌缺血再灌注损伤中,炎症细胞因子参与其过程的多个环节。实验拟验证白细胞介素1、白细胞介素8因子在此过程中的动态变化,并分析其与药物干预的关系。方法:实验于2005-10/2006-11在新乡医学院形态学实验室完成。①实验分组:选择健康Wistar成年大鼠70只,按随机数字表法分为3组:对照组(n=10)、模型组(n=30)和药物组(n=30)。后两组又分为缺血0.5h,再灌注2,4,8,12,24h6个时相点,每个时相点5只。对照组只设12h一个时相点作为总体对照。②实验方法:大鼠麻醉后,药物组在右股静脉注入甲泼尼龙(30mg/kg),对照组及模型组注入生理盐水(0.75mg/kg)。采用夹闭左冠状动脉前降支建立大鼠心肌缺血再灌注损伤模型。对照组只开胸不夹闭。③实验评估:在各时相点观察各组大鼠缺血再灌注后的心肌细胞改变;血清学检测白细胞介素1、白细胞介素8因子的动态表达。结果:①模型组缺血再灌注12h炎细胞浸润最显著,药物组炎细胞呈散在浸润。②模型组和药物组白细胞介素1、白细胞介素8因子质量浓度明显高于对照组[缺血再灌注8h为例,白细胞介素1分别为(99.21±14.37),(85.77±11.31),(21.87±10.32)ng/L;白细胞介素8分别为(794.85±24.07),(536.95±19.72),(103.94±11.59)ng/L,P<0.05],峰值分别在缺血再灌注4,8h;同时相点药物组白细胞介素1、白细胞介素8因子质量浓度明显低于模型组(P<0.05)。结论:白细胞介素1和白细胞介素8因子在心肌缺血再灌注损伤的炎症反应中发挥着重要作用;甲泼尼龙对缺血再灌注损伤心肌有保护作用。  相似文献   
43.
目的:利用微持续与微间隔时间技术,设计了两组相关的实验,对亮度知觉效应和视觉加工方式进行探讨。方法:实验于2006-06在中南民族大学物理楼脑认知实验室进行,所有受试者为年龄20~25岁的大学本科生,视力(含矫正视力)正常,均为右利手。①实验1:被试为10名(男5名,女5名),要求被试分别对n屏依次呈现的亮块的明度和n 1屏依次呈现的亮块的明度进行比较(n≤17)。②实验2:被试为28名(男13名,女15名),实验涉及两个刺激物,先呈现的刺激物由左右两个大小相同、亮度不同的亮块a和b组成,后呈现的刺激物把a和b的位置进行对调,当这两个刺激物依次显示时,要求被试报告左右两边的明度是否存在差异,存在何种差异。结果:①实验1∶1≤n≤3时,100%的被试报告,n 1屏的明度大于n屏的亮度,即n 1>n;4≤n≤10时,70%~90%的被试报告n 1>n;n>10时,50%~70%的被试报告n 1>n;随着n值的增加明度差异也在减小,大约在n=17时达到稳定,n屏和n 1屏的明度区别将很难被看出。②实验2:在L(a)b a,随着a和b的亮度差异减小,左右两边呈现的明度越相似;同样当L(a)相似文献   
44.
Chronic pain is a common problem requiring a multidisciplinary approach. Nursing can offer diverse therapies complementary to the medical-surgical approach. Guidelines for practice and challenges for research are outlined for selected nonpharmacological chronic pain therapies. This article discusses the placebo effect, which is common to all therapies. Placebos can therapeutically empower patients to stimulate their psychophysiologic self-regulation abilities. Effects, theories, ethics, and therapeutic methods of stimulating the placebo effect are explored.  相似文献   
45.
Transmission of human herpesvirus 8 (HHV-8) may occur through various routes including breastfeeding and sexual intercourse. We attempted to detect HHV-8 infection in nine HIV-positive couples discordant for Kaposi's sarcoma who maintained a monogamous sexual relationship for at least one year. By quantitative real-time polymerase chain reaction and HHV-8 genotyping we provide strong evidence for the sexual transmission of HHV-8 in this unique cohort.  相似文献   
46.
Sequence analysis can be used to evaluate transmission networks. We have used retrospective samples to examine two HIV-1 transmission networks established by contact tracing. Regions of the HIV-1 region representing segments of gag and env were amplified by RT-PCR from frozen plasma samples and the sequence of each PCR product was determined. Within one of the networks (composed of 38 subjects) we found only a subset of the tested sequence clusters was consistent with the reported epidemiological linkage. Of 15 presumed transmission events where sequence data were available, 9 could be rejected either by subtype mismatch or by phylogenetic tests. In the other network (composed of 89 subjects) we were able to assess sequences for 26 presumed transmission events, 18 of which were rejected based on subtype discordance. Long lags in time between the time of transmission and the time of sequence sampling (ranging from 2 to 18 years) may limit the sensitivity for the detection of sequence linkage. Also, superinfection and incomplete epidemiological information are other factors that will limit the concordance of phylogenetic reconstruction and reported epidemiological linkage.  相似文献   
47.
RATIONALE AND OBJECTIVES: The capability of wavelet transforms to separate signals into frequency bands is the basis for its use in image compression and storage, data management and transmission, and, recently, extraction of latent images of tissue components from noisy medical images. Analysis of temporal variations of radiofrequency backscatter of intravascular ultrasound with one-dimensional wavelets can detect lipid-laden plaque in coronary arteries with a sensitivity and specificity of >80%. In this study we evaluate the capability of a novel, 3-dimensional isotropic wavelet analysis to perform high resolution, non-directionally biased, statistically reliable, non-invasive discrimination between components of human coronary atherosclerotic plaques in micro-CT. MATERIALS AND METHODS: Coronary artery segments (5-15 mm) were excised at necropsy from 18 individuals with advanced coronary atherosclerosis. Specimens were imaged using a GE Locus SP ex vivo micro-CT scanner and processed for histological correlation (833 sections). The isotropic wavelet constructs were applied to the entire volume of CT data of each arterial segment to distinguish tissue textures of varying scales and intensities. Voxels were classified and plaque characterization achieved by comparing the relative magnitudes of these wavelet constituents to that of several reference plaque tissue components. RESULTS: Processing of micro-CT images via these isotropic wavelet algorithms permitted 3-D, color-coded, high resolution, digital discrimination between lumen, calcific deposits, lipid-rich deposits, and fibromuscular tissue providing detail not possible with conventional thresholding based on Hounsfield intensity units. Using the isotropic wavelets (with histology as the gold standard), lipid-rich pools approaching the size of the filter for the isotropic wavelet algorithm (0.25 mm [250 microns] in length) were identified with 81% sensitivity and 86% specificity. Calcific deposits, fibromuscular tissue, and lumen equal to or larger than the wavelet filter size were detected without error (100% sensitivity and specificity). CONCLUSION: Isotropic wavelet analysis permits high resolution, multi-dimensional identification of coronary atherosclerotic plaque components in micro-CT with sensitivity and specificity similar to that achieved with data obtained invasively (from IVUS in vivo) using one-dimensional wavelets. Further studies are necessary to test the applicability of this technology to clinical, multi-detector scanners.  相似文献   
48.
In this paper we study the connection between coronary artery bypass graft (CABG) operation time and quality. Our quality metric was the improvement in health related quality of life (HRQoL) survey score in a sample of 432 patients admitted to Kuopio University Hospital. Patients were interviewed with a structured questionnaire a day before the procedure and the follow-up questionnaires were mailed 6 and 12 months after the surgery. However, the HRQoL metric used did not have high retest reliability. Subsequently, we did not find any connection between CAGB operation times and HRQoL. Likewise, we did not find the speed of the surgeon to have any connection to HRQoL improvement.  相似文献   
49.
Purpose  To examine the immune response to job strain and insecurity of 88 men working in a university, divided according to age and type of employment. Methods  Anxiety, job strain, job insecurity and subjective symptoms were measured by questionnaires. Blood NK cytotoxic activity was determined by an in vitro method and lymphocyte subpopulations by flow-cytometry analysis. Results  Employees (over 40 years old) in a library showed higher values of job strain, anxiety and subjective symptoms and lower blood NK activity than the controls. The young employees with temporary employment showed high job insecurity and reduced blood NK activity, while the young sanitary staff with temporary position showed normal immune response. NK cytotoxic activity of the recruited men was negatively correlated with anxiety, work load and job insecurity. Conclusions  Not only anxiety and depression but also high levels of job strain and/or insecurity may affect the health status by reducing blood NK activity.  相似文献   
50.
OBJECTIVE: To test the hypothesis that intensive multimodal psychosocial intervention (that includes academic assistance and psychotherapy) combined with methylphenidate significantly enhances the academic performance and emotional status of children with attention-deficit/hyperactivity disorder (ADHD) compared with methylphenidate alone and with methylphenidate combined with nonspecific psychosocial treatment (attention control). METHOD: One hundred three children with ADHD (ages 7-9), free of conduct and learning disorders, who responded to short-term methylphenidate were randomized for 2 years to receive one of three treatments: (1) methylphenidate alone, (2) methylphenidate plus psychosocial treatment that included academic remediation, organizational skills training, and psychotherapy as well as parent training and counseling and social skills training, or (3) methylphenidate plus attention control treatment. Children's function was assessed through academic testing, parent ratings of homework problems, and self-ratings of depression and self-esteem. RESULTS: No advantage was found on any measure of academic performance or emotional status for the combination treatment over methylphenidate alone and over methylphenidate plus attention control. Significant improvement occurred across all treatments and was maintained over 2 years. CONCLUSIONS: In stimulant-responsive young children with ADHD without learning and conduct disorders, there is no support for academic assistance and psychotherapy to enhance academic achievement or emotional adjustment. Significant short-term improvements were maintained over 2 years.  相似文献   
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