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101.
A total of 316 samples of nasopharyngeal aspirate from infants up to two years of age with acute respiratory-tract illnesses were processed for detection of respiratory syncytial virus (RSV) using three different techniques: viral isolation, direct immunofluorescence, and PCR. Of the samples, 36 (11.4%) were positive for RSV, considering the three techniques. PCR was the most sensitive technique, providing positive findings in 35/316 (11.1%) of the samples, followed by direct immunofluorescence (25/316, 7.9%) and viral isolation (20/315, 6.3%) (p < 0.001). A sample was positive by immunofluorescence and negative by PCR, and 11 (31.4%) were positive only by RT-PCR. We conclude that RT-PCR is more sensitive than IF and viral isolation to detect RSV in nasopharyngeal aspirate specimens in newborn and infants.  相似文献   
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OBJECTIVE: CD4+,CD25high regulatory T (Treg) cells play a crucial role in the maintenance of self tolerance and prevention of organ-specific autoimmunity. The presence of many in vivo-preactivated CD4+,CD25++ T cells in patients with systemic lupus erythematosus (SLE) poses a difficulty in discriminating CD25++ activated T cells from CD25high Treg cells. To overcome this problem, we analyzed the phenotype and function of CD4+,CD25high,CD127(-/low) natural Treg (nTreg) cells isolated from the peripheral blood of patients with SLE. METHODS: CD4+,CD25high,CD127(-/low) nTreg cells and CD4+,CD25- responder T (Tresp) cells from patients with SLE and normal donors were separated by fluorescence-activated cell sorting. Cell proliferation was quantified by 3H-thymidine incorporation, and immunophenotyping of the cells was done using FACScan. RESULTS: Comparable percentages of CD4+,CD25high,FoxP3+ T cells were observed in patients with SLE and normal donors. Proliferation of SLE nTreg cells sorted into the subset CD4+,CD25high,CD127(-/low) was significantly decreased compared with that of SLE nTreg cells sorted into the subset CD4+,CD25high (mean +/- SEM 2,223 +/- 351 counts per minute versus 9,104 +/- 1,720 cpm, respectively), while in normal donors, these values were 802 +/- 177 cpm and 2,028 +/- 548 cpm, respectively, confirming that effector cell contamination was reduced. Notably, the suppressive activity of nTreg cells was intact in all groups. However, CD4+,CD25- Tresp cells isolated from patients with active SLE were significantly less sensitive than those from patients with inactive SLE to the suppressive function of autologous or normal donor CD4+,CD25high,CD127(-/low) nTreg cells. Furthermore, a significant inverse correlation was observed between the extent of T cell regulation in suppressor assays and the level of lupus disease activity. CONCLUSION: This study is the first to show that, in human SLE, impaired sensitivity of Tresp cells to the suppressive effects of a comparably functional, highly purified nTreg cell population leads to a defective suppression of T cell proliferation in active SLE. Studies aiming to define the mechanisms leading to Tresp cell resistance might help in the development of highly specific, alternative immunotherapeutic tools for the control of systemic autoimmune diseases such as SLE.  相似文献   
106.

Background  

It is unclear whether appropriate empiric antimicrobial therapy improves outcomes in patients with bacteremia due to Escherichia coli or Klebsiella. The objective of this study is to assess the impact of appropriate empiric antimicrobial therapy on in-hospital mortality and post-infection length of stay in patients with Escherichia coli or Klebsiella bacteremia while adjusting for important confounding variables.  相似文献   
107.
Asymptomatic human carriers of Leishmania chagasi   总被引:6,自引:0,他引:6  
In Brazil, programs based on elimination of infected dogs have not curtailed the spread of visceral leishmaniasis (VL), suggesting that other reservoirs of infection exist. Persons with active VL can infect the sand fly vector, but in endemic areas, persons with asymptomatic infections, whose infectivity to sand flies is unknown, are far more numerous. In this study, a polymerase chain reaction-based assay detected kinetoplast DNA of Leishmania chagasi in the blood of eight of 108 asymptomatic persons living with patients with recently diagnosed VL. These eight persons had low or unmeasurable levels of IgG antibodies to Leishmania, demonstrating the insensitivity of serology for subclinical infection. All eight persons had positive leishmanin skin test results, as did 70% of persons living in households of persons with active VL. Even if a small proportion of such asymptomatic persons are infective to sand flies, they represent a formidable reservoir of infection in endemic areas.  相似文献   
108.
Schwann cells are promising candidates for transplantation strategies in the central nervous system by promoting axonal regeneration. The dog represents a translational model for human spinal cord injury (SCI) for studies with new repair strategies after intervertebral disk herniation (IVDH). To overcome the necessity for an additional surgical procedure, for the first time a protocol for the isolation and purification of canine Schwann cells from spinal nerve biopsies during standard hemilaminectomy in IVDH‐affected paraplegic dogs for potential transplantation has been developed. Purity was assessed by flow cytometry. The results were compared with biopsies from dogs without SCI. Within 26 ± 4 days, 90.2 ± 8.8% p75 neurotrophin receptor (p75NTR)‐positive cells were achieved in IVDH dogs. The total cell count in acute/subacute and chronic IVDH (acute/subacute: 6.82 ± 6.36 × 106; chronic: 2.29 ± 2.00 × 106) differed significantly (p = 0.0120) at the potential time point of transplantation. No differences in culture period and purity were detected between dogs with and without IVDH. Despite the small sample size and the altered environment, the isolation of Schwann cells was successful. Negative influences on isolation and purification due to potential pathological changes at the biopsy site of IVDH‐diseased dogs were ruled out by comparison of Schwann cell pellets from diseased and control dogs. Finally, the functionality of Schwann cells from dogs with IVDH was outlined in co‐culture experiments with canine dorsal root ganglion neurons. In conclusion, nerve root biopsies provide a sufficient number of highly purified and functional Schwann cells within a useful time period for novel therapeutic strategies in dogs with SCI.  相似文献   
109.
Kinesio Taping® elastic tape is increasingly used in physiotherapy treatment. However, there is a lack of scientific research regarding the late effects of its use. This study quantified the late effects of applying the Kinesio Taping® elastic tape by measuring changes in handgrip muscle strength after 24, 48 and 72 h of application. The Kinesio Taping® elastic tape was applied on the dominant and non-dominant limbs of 36 volunteers randomly assigned to three groups: muscle facilitation, muscle inhibition and control group. The statistical test showed there was a statistically significant difference among all groups of dominant limb and non-dominant limb. However, the analysis on intragroup relationship to periods of application (Initial, 24, 48 and 72 h) and the interaction among repeated measures showed there was no statistically significant difference. This result may contribute to the investigation of the late effects of the Kinesio Taping® elastic tape on the physical rehabilitation.  相似文献   
110.
Objective: To independently validate the predictive value of the intensive care requirement score (IRS) in unselected poisoned patients.

Design: Retrospective chart review.

Patients and methods: Five hundred and seventeen out of 585 admissions for acute intoxications could be analyzed. Eleven were excluded for a condition already requiring intensive care unit (ICU) support at admission (e.g., preclinical intubation). A further 57 admissions were excluded due to missing data. The IRS was calculated using a point-scoring system including age, Glasgow Coma Scale, heart rate, type of intoxication, and preexisting conditions. It was then compared to a composite endpoint indicating an ICU requirement (death in hospital, vasopressors, need for ventilation). The endpoint and the point-scoring system were identical to the original publication of the score.

Results and conclusion: Twenty-three out of 517 patients had a complicated clinical course as defined by meeting the endpoint definition. Twenty-one out of 23 complicated courses had a positive IRS (defined as greater or equal 6 points), as compared to 255/494 patients with an uncomplicated clinical course (p?相似文献   
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