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101.
In order to audit United Kingdom laboratory diagnostic and reference services including novel molecular methods for tuberculosis, a questionnaire was sent to laboratories submitting specimens to the PHLS Mycobacterium Reference Unit (MRU) and regional centres and to the Scottish Mycobacteria Reference Laboratory (SMRL) in 1996-7. Nationally, 67.2% of laboratories responded. Most UK laboratories were fully or conditionally CPA accredited and take part in the NEQAS proficiency scheme. On average only 3.3% of primary samples submitted for mycobacterial diagnosis in 1995 produced a mycobacterial culture from approximately half as many patients (that is, a mean of 1488 specimens producing 49 isolates from 23 patients). Potentially over 380,000 specimens are processed for mycobacteria in the UK each year. The majority of laboratories use 4% NaOH +/- NALC for specimen decontamination. Culture on solid media was used by most laboratories and 62.9% also use liquid media. Most laboratories incubated cultures for eight weeks. Few laboratories use molecular diagnostic methods. Laboratories were most likely to use molecular methods for diagnosing tuberculous meningitis and for specimens from immunocompromised patients, although usage was strongly influenced by cost. Within England and Wales 43.9% (47/107) and 56% (61/109) of laboratories wanted a rapid service for rifampicin resistance detection in M tuberculosis from immunocompetent and immunocompromised patients, respectively. In regard to a tuberculous meningitis service, 80.5% (43/112) and 84.3% (102/121) of laboratories wanted this service for immunocompetent and immunocompromised patients, respectively. The quality of reference services was rated as "very good"/"good" by 85.6% of respondents nationally. Rapid molecular amplification diagnostic services were established at the PHLS MRU for rifampicin drug resistance detection nationally and for tuberculous meningitis at the MRU.  相似文献   
102.
103.
Aim: We have designed a study with the objective of describing the clinical impact of other viruses different from the respiratory syncytial virus (RSV) in hospitalized infants with bronchiolitis. Methods: A 3 year prospective study was conducted on infants admitted to the Paediatrics Department of the Severo Ochoa Hospital (Spain). We studied the frequency of 16 respiratory viruses. Clinical characteristics of RSV‐only infections were compared with other single agent viral infections. Results: Positive results were confirmed in 275 (86.5%) of the 318 children studied. A single virus was detected in 196 patients and 79 were dual or multiple viral infections. RSV was detected in 61.3% of total bronchiolitis. Rhinovirus (RV) was 17.4% of the identified virus, followed by human bocavirus (HBoV), adenovirus and metapneumovirus (hMPV). Only RV, HBoV and hMPV were significant as single infections. RSV patients were younger than HBoV (p > 0.0001) and hMPV (p = 0.025). Seasonality was clearly different between them. Children with RSV infection needed treatment in the intensive care unit more frequently than others. Conclusions: In hospitalized infants, RSV was the most frequent agent in bronchiolitis in winter, but other viruses were present in 47% of the patients. RV, HBoV and hMPV had a significant proportion of single infections. Clinical characteristics were similar amongst them, but seasonality was clearly different.  相似文献   
104.
This review summarizes the current literature regarding the ocular complications of hydroxychloroquine. Hydroxychloroquine has been used since the 1950s for the treatment of various rheumatic and dermatologic diseases. Hydroxychloroquine can cause ocular toxicity, with the most serious being an irreversible retinopathy. At the present time, no "gold standard" exists for identification of the ocular toxicity prior to its development. This has led to controversy regarding the recommendations for ophthalmologic examinations for screening patients on hydroxychloroquine.  相似文献   
105.
Halim SS  Ostrowski SE  Lee WT  Ramsingh AI 《Vaccine》2000,19(7-8):958-965
The immunogenicity of soluble peptides can be improved by expression within recombinant microorganisms. The immunogenicity of a peptide expressed within a capsid protein of an attenuated coxsackievirus B4 was evaluated. The insertion site was chosen based on its antigenic structure. A foreign peptide was inserted into a region of the VP1 capsid protein that was identified as a T helper cell epitope. A recombinant virus containing ten amino acids of ovalbumin sequence was genetically stable and retained the biological and physical characteristics of the parental virus. The recombinant was able to elicit a T helper cell response against ovalbumin sequences. This study shows, for the first time, that coxsackievirus can be used as an expression vector and that insertion of heterologous peptides into an immunogenic region is a viable strategy for inducing T helper cell responses against foreign sequences. The implications of this work are that the attenuated coxsackievirus variant may be useful as a vaccine vector for expressing T helper cell epitopes that are important in inducing protective immunity.  相似文献   
106.
In previous studies, bosentan was found to decrease plasma leptin concentrations after myocardial infarction (MI) in rats and had decreased mortality. The present study was undertaken to examine the effect of bosentan on leptin and endothelin‐1 (ET‐1) concentrations in plasma and ET‐1 concentrations in the hippocampus after cardiac arrest (CA) in rats. Studies were performed in 72 rats divided into treated and untreated animals in the following experimental groups: control, 3 min, 10 min, 1 h, 24 h, and 7 days after CA. Bosentan was given daily 2 h before CA or decapitation, 7 days, by gavage at a dose of 100 mg/kg. Plasma leptin concentration decreased in the early period after CA, and being elevated in 24 h, normalized 1 week later. Bosentan kept plasma leptin concentration at the control level in the postischemic period. Plasma ET‐1 concentration significantly increased during the postischemic period. Bosentan produced the elevation of plasma ET‐1 concentration in the preischemic period and kept the level of ET‐1 at control values after CA. Concentration of ET‐1 in the hippocampus was significantly lower 24 h after CA and was elevated after 1 week. The most dramatic effect of bosentan on ET‐1 concentration was in the hippocampus, where it significantly decreased during the entire postischemic recovery period. We postulate an important effect of bosentan on concentration of ET‐1 and leptin in plasma and ET‐1 in the brain after global cerebral ischemia caused by CA. Drug Dev Res 64:137–144, 2005. © 2005 Wiley‐Liss, Inc.  相似文献   
107.
引用违法传递概念设计合成了11个C-末端含氧代赖氨酸二肽,进行抗深部致病菌-白念珠菌活性试验,体外实验结果显示极强的抑菌活性,MIC在12.5~0.8μg/disk之间,较母体氧化赖氨酸大50~135倍(克分子比。  相似文献   
108.
As an alternative to performing interventional radiology on inpatients under the care of internists and surgeons, the authors have established a cardiovascular radiology admitting service for well-screened, elective patients. The patients are admitted under the care of a cardiovascular radiology fellow and a staff physician. From April 1982 to December 1983, 133 patients were admitted to the service. Patients are cared for in a surgical ward or in an intermediate unit, as determined by the clinical situation. Advantages of this approach include a broader patient referral base, improved rapport with clinical colleagues and patients, improved follow-up data, and rapid evaluation and treatment, resulting in short hospital stays. The major disadvantages involve the commitment of time and staff necessary to provide quality care. The concept of the interventional radiologist in the role of admitting physician has important implications in terms of negotiations for additional financial compensation, commensurate with the skill and time required for performing these procedures and caring for the patient.  相似文献   
109.
Fujita  H; Doi  K; Chan  HP; Giger  ML; Duda  EE 《Radiology》1985,155(3):799-803
Two types of phantoms were developed with which to evaluate the overall performance of digital subtraction angiography (DSA) systems. A dynamic phantom, called a "fish bone" phantom, consists of polyethylene tubes that simulate blood vessels with various lesions, such as stenoses, ulcers, and aneurysms. With this phantom, washout curves were obtained representing the relationship between iodine content and time. It will be useful for qualitative assessment of DSA images, evaluation of different image-processing schemes, and studies of blood flow analysis. A static phantom, called a "C-D" phantom, can be used for measurement of quantitative contrast-detail (C-D) diagrams and for daily monitoring of DSA systems. This was constructed of tubes of seven different diameters (2.15-0.28 mm) and 14 different concentrations of contrast medium (100%-1.1% Renografin-76 [meglumine and sodium diatrizoate]). The C-D diagrams were determined from an observer performance study using C-D phantom images obtained at four different DSA settings.  相似文献   
110.
Isthmic spondylolysis of the lumbar spine: MR imaging at 1.5 T   总被引:4,自引:0,他引:4  
The appearance on magnetic resonance (MR) images of the normal pars interarticularis in 13 patients was reviewed and contrasted with that of the pars in eight patients with spondylolysis. The pars defect usually had an intermediate signal intensity with all pulse sequences; however, this intensity was somewhat variable depending on the exact ratio of cartilage, fat, and fluid within each bone defect. The pars defect was best seen with spin-echo 600/20 (repetition time msec/echo time msec) images. In three cases, out-of-phase images showed the spondylolysis best, because of extension of fat to the borders of the defect. The sagittal view allowed one to separate spondylolysis from the joint space of posterior facets since the orientation of the defects is perpendicular to the facets; thus, a common pitfall encountered with cross-sectional axial imaging techniques is avoided. MR imaging poorly delineated bone fragments around the defect, which may produce nerve root impingement, but revealed other numerous complications that occur with spondylolysis, including spondylolisthesis and herniation of the disk above.  相似文献   
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