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191.
Early proliferation of CCR5(+) CD38(+++) antigen-specific CD4(+) Th1 effector cells during primary HIV-1 infection 总被引:4,自引:0,他引:4
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Zaunders JJ Munier ML Kaufmann DE Ip S Grey P Smith D Ramacciotti T Quan D Finlayson R Kaldor J Rosenberg ES Walker BD Cooper DA Kelleher AD 《Blood》2005,106(5):1660-1667
We investigated whether HIV-1 antigen-specific CD4(+) T cells expressed the viral coreceptor CCR5 during primary HIV-1 infection (PHI). In the peripheral blood of subjects with very early PHI (< 22 days after onset of symptoms), there was a 10- to 20-fold increase in the proportion of highly activated (CD38(+++)) and proliferating (Ki-67(+)) CD4(+) T cells that expressed CCR5(+), and were mostly T-cell intracellular antigen-1 (TIA-1)(+) perforin(+) granzyme B(+). Inthe same patient samples, CD4(+) T cells producing interferon (IFN)-gamma in response to HIV group-specific antigen (Gag) peptides were readily detected (median, 0.58%) by intracellular cytokine assay-these cells were again predominantly CD38(+++), Ki-67(+), and TIA-(++), as well as Bcl-2(low). On average, 20% of the Gag-specific CD4(+) T cells also expressed interleukin-2 (IL-2) and were CD127 (IL-7R)(+). Taken together, these results suggest that Gag-specific T-helper 1 (Th1) effector cells express CCR5 during the primary response and may include precursors of long-term self-renewing memory cells. However, in PHI subjects with later presentation, antigen-specific CD4(+) T cells could not be readily detected (median, 0.08%), coinciding with a 5-fold lower level of the CCR5(+)CD38(+++) CD4(+) T cells. These results suggest that the antiviral response to HIV-1 infection includes highly activated CCR5(+)CD4(+) cytotoxic effector cells, which are susceptible to both apoptosis and cytopathic infection with HIV-1, and rapidly decline. 相似文献
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William R. Yates Maureen Martin Douglas LaBrecque Don Hillebrand Michael Voigt Debra Pfab 《Alcoholism, clinical and experimental research》1998,22(2):513-517
Six months of abstinence from alcohol is a commonly used criterion for liver transplantation eligibility for patients with alcoholic cirrhosis. There is limited evidence to document the validity of this criterion with regard to risk of alcoholism relapse. Ninety-one patients with alcoholic cirrhosis were interviewed for relapse risk using the High Risk Alcoholism Relapse (HRAR) Scale. The HRAR model can be used to predict relapse risk independent of duration of sobriety and therefore can be used to examine the validity of the 6 months of abstinence criteria in this clinical population. The two methods demonstrated poor to fair agreement. Agreement was highest with a cutoff allowing a 5% 6-month relapse risk when 79% agreement ( k = 0.56) was demonstrated between the two methods. Using the 6-month abstinence criterion alone disallows a significant number of candidates who have a low relapse risk based on their HRAR score. The validity of the 6-month abstinence criterion is supported somewhat by comparison with the HRAR model. However, use of the 6-month abstinence criterion alone forces a significant number of patients with a low relapse risk by HRAR to wait for transplant listing. A relapse risk model based on an estimate of alcoholism severity in addition to duration of sobriety may more accurately select patients who are most likely to benefit from liver transplantation. 相似文献
194.
Dr. M. Leela Prasad M.D. Don R. Read M.D. Herand Abcarian M.D. 《Diseases of the colon and rectum》1981,24(6):456-461
Anorectal suppurations are quite common. Supralevator abscesses, previously regarded as a rare subgroup, were seen in 9.1
per cent of 506 patients admitted to Cook County Hospital in a two-year period. Aggressive supportive management was followed
by early, adequate drainage through single or multiple radial perianal incisions or through the rectum whenever indicated.
When fistulas were identified, either a primary fistulotomy or a two-stage fistulotomy using a seton was performed in the
majority of cases. Important factors in the prevention of morbidity and mortality included debridement of all necrotic tissue,
careful bacteriologic studies and judicious use of antibiotics, close postoperative observation, and long-term follow-up of
the patients.
Read at the meeting of the American Society of Colon and Rectal Surgeons, Hollywood, Florida, May 11 to 16, 1980. 相似文献
195.
Dunkelgrun M Welten GM Goei D Winkel TA Schouten O van Domburg RT van Gestel YR Flu WJ Hoeks SE Bax JJ Poldermans D 《The American journal of cardiology》2008,102(7):797-801
The role of uric acid as an independent marker of cardiovascular risk is unclear. Therefore, our aim was to assess the independent contribution of preoperative serum uric acid levels to the risk of 30-day and late mortality and major adverse cardiac event (MACE) in patients scheduled for open vascular surgery. In total, 936 patients (76% male, age 68 +/- 11 years) were enrolled. Hyperuricemia was defined as serum uric acid >0.42 mmol/l for men and >0.36 mmol/l for women, as defined by large epidemiological studies. Outcome measures were 30-day and late mortality and MACE (cardiac death or myocardial infarction). Multivariable logistic and Cox regression analysis were used, adjusting for age, gender, and all cardiac risk factors. Data are presented as odds ratios or hazard ratios, with 95% confidence intervals. Hyperuricemia was present in 299 patients (32%). The presence of hyperuricemia was associated with heart failure, chronic kidney disease, and the use of diuretics. Perioperatively, 46 patients (5%) died and 61 patients (7%) experienced a MACE. Mean follow-up was 3.7 years (range: 0 to 17 years). During follow-up, 282 patients (30%) died and 170 patients (18%) experienced a MACE. After adjustment for all clinical risk factors, the presence of hyperuricemia was not significantly associated with an increased risk of 30-day mortality or MACE, odds ratios of 1.5 (0.8 to 2.8) and 1.7 (0.9 to 3.0), respectively. However, the presence of hyperuricemia was associated with an increased risk of late mortality and MACE, with hazard ratios of 1.4 (1.1 to 1.7) and 1.7 (1.3 to 2.3), respectively. In conclusion, the presence of preoperative hyperuricemia in vascular patients is a significant predictor of late mortality and MACE. 相似文献
196.
Comparing a single case to a control sample: differences in distribution versus differences in means
There is no abstract associated with this paper 相似文献
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Objective
The purpose of this research is to gain an understanding of the asthma perceptions of older adults and identify gaps in their asthma knowledge.Methods
In regional New South Wales, Australia, a stratified, random sample of 4066 adults, aged 55 years and over, both with and without an asthma diagnosis, completed a survey based on the Health Belief Model about asthma knowledge and perceptions.Results
Almost half of the sample had experienced symptoms of breathlessness in the past four weeks. Breathlessness was a predictor of lower health ratings and poorer mood. Older adults reported low susceptibility to developing asthma. The sample demonstrated poor knowledge of key asthma symptoms including shortness of breath, tightness in the chest and a cough at night.Conclusion
There is a general lack of asthma awareness in this age group. This could result in not seeking medical help, and thus a reduced quality of life.Practical Implications
Older adults should be made aware of key symptoms and the prevalence of asthma in the older adult population, and be empowered to take control of their respiratory health. Audience segmentation for an intervention should be based on recent experience of breathlessness and asthma diagnosis. 相似文献200.
Sashika M. Yalage Don Leigh M. Schmidtke Joanna M. Gambetta Christopher C. Steel 《Research in microbiology》2021,172(1):103788
Aureobasidium pullulans is a yeast-like fungus that produces volatile organic compounds (VOCs) with antifungal properties. VOCs have the potential to trigger the production of intracellular reactive oxygen species (ROS), lipid peroxidation and electrolyte loss in microorganisms. The relationship among A. pullulans VOCs, induced ROS accumulation and electrolyte leakage was investigated in Botrytis cinerea and Alternaria alternata in vitro. Exposure to a mixture of A. pullulans VOCs: ethanol, 2-methyl-1-propanol, 3-methyl-1-butanol and 2-phenylethanol, resulted in electrolyte leakage in both B. cinerea and A. alternata. Fluorescence microscopy using 2′,7′-dichlorofluorescein diacetate indicated triggered ROS accumulation in exposed fungal mycelia and the presence of the superoxide radical was evident by intense red fluorescence with dihydroethidium. Partial inhibition of enzymes of the mitochondrial respiratory chain complex I of B. cinerea and A. alternata by pre-treatment with rotenone reduced ROS accumulation in hypha exposed to A. pullulans VOCs and reversed the VOCs inhibition of fungal growth. Scanning electron micrographs revealed that B. cinerea and A. alternata hypha exposed to A. pullulans VOCs had altered cell wall structures. Our findings give insights into the potential mechanisms involved in the antifungal properties of A. pullulans in the suppression of B. cinerea and A. alternata growth in vitro. 相似文献