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21.
To address concerns over the prevalence of silent (antibody-negative) infections among blood donors and high-risk populations, a combination of proviral amplification by polymerase chain reaction (PCR) and viral isolation by co-culture techniques was employed to resolve the human immunodeficiency virus type 1 (HIV-1) infection status of well-characterized groups of suspect blood donors and others identified in the blood bank setting. No silent infections were found in 65 follow-up samples from 26 persistently HIV-1-seroindeterminate blood donors, 16 persistently seronegative heterosexual partners of infected transfusion recipients, and 6 high-risk seronegative homosexual men identified through donor look-back investigations. In contrast, 21 seropositive controls tested positive. These results suggest a low prevalence of persistently silent infections in at-risk populations, even in high HIV prevalence regions. The PCR assay, with a co-detected internal positive control, and appropriate confirmatory algorithms, was found to be a useful direct assay to rule out infection, especially in concert with confirmatory virus isolation. 相似文献
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A retrospective analysis was made of the data on 60 patients with stage T1 glottic carcinoma (43 T1a, 17 T1b) who received radiation therapy and 17 patients with T1a disease who underwent laser excision as the primary treatment modality. Patients who received radiation therapy achieved 3- and 5-year actuarial local control rates of 92% and 89% for T1a and 77% and 77% for T1b disease, respectively. In patients who underwent laser excision (all with T1a disease), the 3-year local control rate was 77%. Of the 42 evaluable irradiated T1a patients, 31 (74%) had a normal to near-normal voice, eight (19%) had mild or intermittent hoarseness, and three (7%) had persistent hoarseness. Of the 13 evaluable patients in the laser-excision group, four (31%) had a normal to near-normal voice, five (38%) had mild or intermittent hoarseness, and four (31%) had persistent hoarseness. The difference in the quality of voice between these two groups is statistically significant (P = .012), although the ultimate local control rate after salvage therapy for irradiated patients (97%) was similar to that for laser-excision patients (94%). 相似文献
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ME Pichichero S McLinn HA Rotbart MA Menegus M Cascino BE Reidenberg 《Pediatrics》1998,102(5):1126-1134
OBJECTIVE: To characterize the acute clinical course and economic burden of nonpolio enteroviral (NPEV) illness in the summer/fall season as seen in private pediatric practice. METHODS: We prospectively studied 380 children aged 4 to 18 years with systemic NPEV syndromes presenting to private suburban pediatric practices. Seventy-three asymptomatic controls were concurrently enrolled. Clinical diagnosis of NPEV illness was based on the presence of fever plus at least one of the following: headache and stiff neck (n = 2); myalgia and malaise (n = 105); nonpuritic maculopapular rash (n = 10); papulovesicular stomatitis (n = 214); papular rash of the hands, feet, and mouth (H/F/M) (n = 30); or pleurodynia (n = 11). Study participants were enrolled during a 4-month time span (July-October, 1994) and followed daily for 14 days. A parent symptom diary card and twice weekly phone contacts by study nurses characterized the illness to include the frequency of health care contacts, the necessity for laboratory tests, medication use, and school/work absenteeism. RESULTS: Three hundred seventy-two (98%) children completed the study; 122 (33%) of the patients were confirmed to be infected with NPEV. Confirmed NPEV infection was more frequently observed in Rochester, NY (85/147 = 58%) than in Scottsdale, AZ (32/224 = 14%). The age group 4 to 12 years comprised 79% to 90% of the enrollees, depending on the syndrome. Median duration of illness and median number of missed days of school/summer camp/work for the enrolled patients was: meningitis (7 days ill, 2 days missed), myalgia/malaise (9 days ill, 3 days missed), rash (6 days ill, 4 days missed), stomatitis (7 days ill, 2 days missed), H/F/M (7 days ill, 1 day missed), and pleurodynia (8 days ill, 3 days missed). Direct medical costs varied from $69 per case to $771 per case and indirect costs, attributable primarily to parent missed work and/or sick-child care, varied from $63 per case to $422 per case for H/F/M and meningitis, respectively. In households, H/F/M spread to 50% of siblings and 25% of parents. CONCLUSIONS: In our study population, NPEV infection: 1) caused sufficient illness to prompt physician visits in summer and fall; 2) occurred more frequently in 4 to 12 year olds than in adolescents; 3) produced various clinical syndromes concurrently during the same months in the same season of a given year; 4) varied in occurrence geographically; 5) was characterized by numerous symptoms of longer duration than previously recognized; and 6) produced a significant economic impact by generating both direct and indirect costs. 相似文献
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CJ Barry AIIP CRA AAIMBI RL Cooper FRACO FRACS RH Eikelboom BE PhD 《Clinical & experimental ophthalmology》1997,25(2):137-143
Purpose: To retrospectively examine the optic disc photographs of a glaucoma population for optic disc haemorrhages, vascular occlusions and vascular abnormalities. Methods: The optic disc photographs of 906 eyes of glaucoma and suspect glaucoma patients were examined. Optic disc photographs were taken annually, where possible, with the follow-up period varying between 1 and 14 years duration (mean, 2.89). Glaucoma patients are regularly reviewed every 4–6 months and glaucoma suspects every 1–2 years, depending on the ophthalmologist. Low-tension glaucoma patients were reviewed more frequently (mean, every 2.6 months). The results of the findings were compared to a control group of 39 subjects with a mean follow-up period of 7 years, using Fisher's exact test. Results: It was found that during the period under review, 7.4% (n= 67) of eyes had optic disc haemorrhages. The highest frequency of optic disc haemorrhages (37.5%) was found in the low tension glaucoma group (P= 0.0001) followed by 11.4% of primary open-angle glaucoma eyes (P= 0.03). In the normal group there were three eyes with optic disc haemorrhages and one with a disc collateral, which constitutes 5.1% vascular changes in this sub-group. Of the study eyes 2.8% had central retinal vein occlusions, 1.3% branch vein occlusion, 1.2% disc vessel abnormalities (loops) and 1.1% disc collaterals. Discrete nerve fibre layer haemorrhages and microaneurysms were found in 0.8% and 1.8% of eyes, respectively. Conclusions: A total of 16.8% of the eyes observed in this study had either disc haemorrhages or vascular changes. The underlying trend of vascular and haemorrhagic changes in glaucoma are demonstrated in this sample, which is in general agreement with previous studies. The high percentage of optic disc haemorrhages in low tension glaucoma is highlighted. The presence of microaneurysms and nerve fibre layer haemorrhages is interesting but of unknown significance. 相似文献
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The activation of the contact phase of coagulation by physiologic surfaces in plasma: the effect of large negatively charged liposomal vesicles 总被引:1,自引:0,他引:1
The endogenous, negatively charged surface that induces activation of the contact coagulation factors was investigated in plasmas taken from women in late pregnancy and control subjects of child-bearing age. The plasmas from the two groups of subjects were incubated at 4 degrees C for 24 hours either in plastic or in glass tubes and the factor VII coagulant activity (VIIc) was assayed in the treated plasmas. The activation of factor VII under these conditions involves the generation of enzymes derived from factor XII (XIIa). The contact surface is rate- limiting for the activation of factor VII in the plasmas in both groups of subjects and can be supplemented by large multilamellar liposomal vesicles carrying the appropriate density of negative charge. The size of these vesicles is within the range of sizes of the large lipoprotein particles (chylomicrons, very low and intermediate-density lipoproteins). The relationship between the density of negative charge on the liposomal vesicles and VIIc was similar in the late pregnancy and the control plasmas incubated in plastic tubes. At a saturating density of negative charge the observed relative VIIc was similar in both sets of plasmas. The incubation of late pregnancy or control plasma in plastic tubes in the presence of sodium stearate caused VIIc to increase with increasing concentration of the added fatty acid. These results suggest that large lipoprotein particles carrying the appropriate free fatty acid at a sufficient density of negative charge could provide the contact surface that induces the generation of factor XIIa and the subsequent activation of factor VII. Moreover, plasmas from women in late pregnancy have a higher concentration of potential surface and a higher density of negative charge than the plasmas from nonpregnant women. 相似文献
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