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51.
The case is reported of a patient who developed an acute arthropathy, which was initially diagnosed as acute septic arthritis. The true diagnosis of rat bite fever due to Streptobacillus moniliformis was delayed because of difficulty in growing the organism, which has fastidious growth requirements. The patient had no history of rat bite, which is the usual form of transmission of this disease.  相似文献   
52.
53.

Background  

Identifying novel TB diagnostics is a major public health priority. We explored the diagnostic characteristics of antimycobacterial lymphocyte proliferation assays (LPA) in HIV-infected subjects with latent or active TB.  相似文献   
54.
The UK National Osteoporosis Society (NOS) has recently issued new guidelines on the use of peripheral x-ray absorptiometry (pDXA) devices in managing osteoporosis. The NOS guidelines recommend a triage approach in which patients bone mineral density (BMD) measurements are interpreted using upper and lower thresholds specific to each type of pDXA device. The thresholds are defined so that patients with osteoporosis at the hip or spine are identified with 90% sensitivity and 90% specificity. Patients with a pDXA result below the lower threshold are likely to have osteoporosis at the hip or spine, patients with a result above the upper threshold are unlikely to have osteoporosis, while those between the two thresholds require a hip and spine BMD examination for a definitive diagnosis. This report presents data from a multicenter study to establish the triage thresholds for a range of pDXA devices in use in the UK. The subjects were white female patients aged 55–70 years who met the normal referral criteria for a BMD examination. For each device, at least 70 women with osteoporosis at the hip or spine and 70 women without osteoporosis were enrolled. All women had hip and spine BMD measurements using axial DXA systems that were interpreted using the National Health and Nutrition Examination Survey (NHANES) reference range for the hip and the manufacturers reference ranges for the spine. Data are presented for five different devices: the Osteometer DTX-200 (forearm BMD), the Schick AccuDEXA (hand BMD), the GE Lunar PIXI (heel BMD), the Alara MetriScan (hand BMD), and the Demetech Calscan (heel BMD). The clinical measurements were supplemented by theoretical modeling to estimate the age dependence of the triage thresholds and the effect of the correlation coefficient between pDXA and axial BMD on the percentage of women referred for an axial BMD examination. In summary, this study provides thresholds for implementing the new NOS guidelines for managing osteoporosis using pDXA devices. The figures reported apply to postmenopausal white women aged 55–70 years who meet the conventional criteria for a BMD examination. The results confirm that the thresholds are specific to each type of pDXA device and that the NOS triage algorithm requires 40% of women to have an axial DXA examination.On behalf of the National Osteoporosis Society Bone Densitometry Forum.  相似文献   
55.
Minactivin expression in human monocyte and macrophage populations   总被引:4,自引:0,他引:4  
Adherent monolayer cultures of human blood monocytes, peritoneal macrophages, bone marrow macrophages, and colonic mucosa macrophages were examined for their ability to produce and secrete minactivin, a specific inactivator of urokinase-type plasminogen activator. All except colonic mucosa macrophages produced and secreted appreciable amounts of minactivin, but only blood monocytes were stimulated by muramyl dipeptide (adjuvant peptide) to increase production. The minactivin from each of these populations could be shown to preferentially inhibit urokinase-type plasminogen activator and not trypsin, plasmin, or "tissue"-type plasminogen activator (HPA66). A plasminogen-activating enzyme present in monocyte cultures appeared unaffected by the presence of minactivin and could be shown to be regulated independently by dexamethasone.  相似文献   
56.

Background

To date, there are limited radiation dose data on CT-guided procedures in pediatric patients.

Objective

Our goal was to quantify the radiation dose associated with pediatric CT-guided drain placement and follow-up drain evaluations in order to estimate effective dose.

Materials and methods

We searched the electronic medical record and picture archiving and communication system (PACS) to identify all pediatric (<18 years old) CT-guided drain placements performed between January 2008 and December 2013 at our institution. We compiled patient data and radiation dose information from CT-guided drain placements as well as pre-procedural diagnostic CTs and post-procedural follow-up fluoroscopic abscess catheter injections (sinograms). Then we converted dose–length product, fluoroscopy time and number of acquisitions to effective doses using Monte Carlo simulations and age-appropriate conversion factors based on annual quality-control testing.

Results

Fifty-two drainages were identified with mean patient age of 11.0 years (5 weeks to 17 years). Most children had diagnoses of appendicitis (n=23) or inflammatory bowel disease (n=11). Forty-seven patients had diagnostic CTs, with a mean effective dose of 7.3 mSv (range 1.1–25.5 mSv). Drains remained in place for an average of 16.9 days (range 0–75 days), with an average of 0.9 (0–5) sinograms per patient in follow-up. The mean effective dose for all drainages and follow-up exams was 5.3 mSv (0.7–17.1) and 62% (32/52) of the children had effective doses less than 5 mSv.

Conclusion

The majority of pediatric patients who have undergone CT-guided drain placements at our institution have received total radiation doses on par with diagnostic ranges. This information could be useful when describing the dose of radiation to parents and providers when CT-guided drain placement is necessary.
  相似文献   
57.
Miles S  Fordham R  Mills C  Valovirta E  Mugford M 《Allergy》2005,60(8):996-1003
Both immunoglobulin E (IgE)-mediated food allergy and food intolerance can lead to many changes in personal behaviour and health care resource use which have important economic consequences. These costs will impact directly, indirectly and intangibly on both individuals and society in general. It is important to measure the cost of illness (COI) of food allergy as a first step in developing and evaluating measures to reduce and control the burden of illness. This paper outlines a framework for assessing COI of food allergy from different viewpoints. It offers a structure for identifying the different cost impacts on allergic and nonallergic consumers, food producers and society as a whole, and for scoping, measurement and valuation of relevant costs. Within this structure, the existing literature is reviewed. This review illustrates the lack of information and clear methodology for assessing costs of food allergy. The paper concludes that there is a need for a more structured research programme to generate data essential for future evaluations of procedures and technologies for the diagnosis, treatment and management of food allergy.  相似文献   
58.
Skin tests and lymphocyte proliferation assays (LPA) were performed with Mycobacterium avium sensitin on patients with AIDS. Among 139 subjects, 13% had positive skin test results and 32% had positive LPA results. The LPA may be a more sensitive indicator of prior M. avium infection in this population.  相似文献   
59.
To elucidate the role of innate immunity in susceptibility to the animal model of multiple sclerosis, experimental autoimmune encephalomyelitis (EAE), we induced EAE by immunization with spinal cord homogenate (SCH) plus complete Freund adjuvant or carbonyl iron in 3 inbred rat strains. Lewis are considered "susceptible," PVG/c-Rt7a (PVG) as "semisusceptible," and Brown Norway (BN) as "resistant" to EAE. Immunization with SCH-carbonyl iron resulted in clinical disease in all 3 strains, but the pathologic features of EAE in the resistant BN and the semisusceptible PVG rats differed from those in the Lewis and PVG model of EAE induced with SCH-complete Freund adjuvant. In BN and PVG rats, there were numerous inflammatory lesions with prominent involvement of microglia and, to a lesser extent, perivascular macrophages. These data suggest that different levels of activation of the innate immune system by different adjuvants determine whether EAE will or will not develop. Accordingly, the widely accepted scale of susceptibility to EAE development (Lewis > PVG > BN) should be revised because it does not take into account the important contribution of the composition of the adjuvant to the quality and quantity of the innate immune response and, consequently, to the generation and extent of the pathogenic T-cell-mediated, that is, adaptive, autoimmune disease.  相似文献   
60.
Tests for polymorphonuclear cell (PMN) chemotaxis, adherence, and electrophoretic mobility (EPM) were carried out on blood PMN isolated from 27 normal subjects, 16 patients with uncomplicated rheumatoid arthritis (RA), and 9 patients with Felty's syndrome. Chemotaxis was measured by a modification of the Boyden chamber technique, adherence by retention of cells on nylon fibre columns, and EPM in a cylindrical electrophoretic assembly. There was no significant difference between the chemotactic migration of normal and rheumatoid PMN as assessed by the leading front measurement. However, PMN from patients with Felty's syndrome showed significantly reduced chemotaxis (P less than 0.001). Computerised image analysis showed this impaired migration to be due to an overall reduction in cell motility rather than loss of a subset cells. Activated serum from patients with RA and Felty's syndrome were as good chemoattractants as activated pooled AB serum. There was no significant difference in the adhesiveness of PMN from normal persons and rheumatoid patients, though PMN from patients with Felty's syndrome did show a trend to lower adhesiveness. Both RA and Felty's syndrome patients had an increase in the proportion of PMN of lower surface charge than controls. Direct correlations were observed between cells of high surface charge and nonadhesiveness.  相似文献   
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