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BACKGROUND: The diffuse infiltrative lymphocytosis syndrome (DILS) in HIV patients is characterized by the persistence of CD8-circulating lymphocytes and lymphocytic infiltration, predominantly in salivary glands. METHODS: We examined seven HIV-positive patients with bilateral parotid enlargement and sicca symptoms. Minor labial salivary gland biopsies were performed in all patients and submitted for histopathological analysis and immunohistochemistry for CD4, CD8, cytomegalovirus (CMV), LMP-EBV protein, and HIV p-24 protein. RESULTS: In all cases, lymphocytic infiltration of the minor salivary glands, mainly periductal, was found. Acinar atrophy, ductal ectasia, and mild to moderate fibrosis were also observed. We noticed strong immunohistochemical reaction for LMP-EBV and p-24 proteins in ductal cells in all cases, while staining for CMV was consistently negative. The lymphocytes were positive for CD8, but consistently negative for CD4. CONCLUSIONS: A role of Epstein-Barr virus (EBV) and HIV, but not CMV, in the pathogenesis of DILS, is suggested by our immunohistochemical findings.  相似文献   
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Two yeast-based bioassays were used to assess the endocrine activity potential of transformation products formed during the ozonation of water containing a variety of pesticides (propiconazole, atrazine, 2,4-dichlorophenoxyacetic acid [2,4-D], tebuconazole, climbazole, myclobutanil, irgarol, terbutryn, dicamba, mecoprop and diuron). Ozone experiments were conducted first in reverse osmosis water to isolate the effects of the pesticides and then in synthetic wastewater and wastewater effluent to investigate whether the results translated to more complex matrices. The findings demonstrate the recalcitrant nature of most pesticides during ozonation, with removals below 50%, except for irgarol, terbutryn and climbazole with removals up to 70%. This study is the first one to investigate the removal of the fungicides myclobutanil and tebuconazole by ozonation and is one of the first studies to investigate the androgenic activity of ozonation transformation products of contaminants of emerging concern. These findings also demonstrated that during ozonation the initial anti-androgenic activity was removed while the estrogenic activity remained undetected and the androgenic activity increased to levels up to 60% of the anti-androgenic activity of the DHT control. These results indicate that bioactivity should be considered in the evaluation of treatment performance and risks assessment associated to wastewater discharges.  相似文献   
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During a study examining causes of diarrhea from May 2004 to May 2005, 808 stool specimens were collected from patients with acute diarrhea in Tehran. Fecal samples were cultured and identified according to the standard biochemical methods. Molecular identification of enteropathogens was carried out by amplification of their virulence genes by polymerase chain reaction. A total of 369 (45.6%) bacterial pathogens were recovered from 808 patients as follows: Shigella spp., 155 (45.6%); diarrheagenic Escherichia coli 143 (38.8%); Salmonella spp., 51 (13.8%); and Campylobacter spp., 20 (5.4%). Most of the diarrheagenic E. coli were Shiga toxin-producing E. coli, with 64 (44.7%) isolates, followed by 47 (32.9%) enterotoxigenic E. coli isolates; among Shigella spp. isolates, 69 (44.5%) Shigella flexneri were predominant. The molecular diagnosis of enteropathogens yielded a more accurate characterization of the prevalence of diarrhea-causing bacterial strains in Iran. The present study revealed a high prevalence of Shigella and diarrheagenic E. coli as the predominant causes of bacterial diarrhea in this region of the world. These two types of bacteria should therefore be considered when designing preventive strategies for people living in Iran.  相似文献   
35.
Aim: Low back pain (LBP) is the second most frequent reason for seeking medical advice. Various treatments are proposed from no intervention, to analgesics, rest, exercises, local interventions and surgical procedures. Results and outcomes are differently reported. Back School (BS), a combination of patient education and physical exercises, seems to have good results. The aim of this study was to check the effect of BS in factory workers. Patients and Methods: All (70) workers were interviewed and 26 of them (37.1%) had chronic LBP. Secondary causes were excluded. Anatomy, physiology, biomechanics of the spine, correct postures at work and back exercises were taught. Pain on a visual analog scale (VAS) of 0–100, and Short Form (SF)‐36 health survey were applied, before, at the end of BS sessions, and 3 months after BS. Analysis was done by t‐test, Wilcoxon and Pearson’s correlation test. Results: The mean VAS on pain before BS was 43.4 ± 22.3, improving to 38.6 ± 17.5 at the end of BS. The difference was not significant (P = 0.19). The mean VAS improved to 27.5 ± 20 at 3 months after BS. The difference was significant compared to before BS (P = 0.001). The quality of life measured by the SF‐36 questionnaire, did not improve significantly, except for two of its eight subgroups (Role Physical, Social Functioning) at the end of BS, and two of its subgroup (Mental Health, Social Functioning) at 3 months after BS. Conclusion: Among industrial workers, BS is mainly effective on pain, but is less evident on SF‐36.  相似文献   
36.
BACKGROUND: The ability to visualize subsurface blood vessels and measure flow may be useful in certain experimental and clinical settings. METHODS: Color Doppler optical coherence tomography was used to visualize and measure blood flow in subsurface vessels in vivo in a rat skin flap model. Local "hemostatic" interventions (epinephrine or sclerosant injection, heat probe, and laser) were then applied and imaging was repeated. The skin flap was evaluated histologically. RESULTS: Subsurface blood vessels were easily visualized in cross-section, and vessel diameter and bidirectional blood flow velocity were readily measured. Color Doppler optical coherence tomography demonstrated that flow was significantly reduced after epinephrine injection and became undetectable after the other interventions. This correlated with pathologic evidence of vessel damage in all interventions, except for epinephrine injection. Although vessel response was as predicted to most interventions, the response to epinephrine was only temporary, and limited application of heat alone from the heat probe halted flow without visually apparent surface injury. CONCLUSIONS: Color Doppler optical coherence tomography provides high-resolution, cross-sectional flow imaging in subsurface blood vessels. Color Doppler optical coherence tomography is potentially a better technique for the study of existing and new hemostatic intervention in the laboratory. Potential future clinical applications include monitoring of the response to hemostatic modalities.  相似文献   
37.
Success in sandwich technique procedures can be achieved through an acceptable bond between the materials. The aim of this study was to compare the effect of 35% phosphoric acid and Er,Cr:YSGG laser on shear bond strength of conventional glass-ionomer cement (GIC) and resin-modified glass-ionomer cement (RMGIC) to composite resin in sandwich technique. Sixty-six specimens were prepared from each type of glass-ionomer cements and divided into three treatment groups as follows: without pretreatment, acid etching by 35% phosphoric acid for 15 s, and 1-W Er,Cr:YSGG laser treatment for 15 s with a 600-μm-diameter tip aligned perpendicular to the target area at a distance of 1 mm from the surface. Energy density of laser irradiation was 17.7 J/cm2. Two specimens in each group were prepared for evaluation under a scanning electron microscope (SEM) after surface treatment and the remainder underwent bonding procedure with a bonding agent and composite resin. Then the shear bond strength was measured at a crosshead speed of 0.5 mm/min. Two-factor analysis of variance and post-hoc Tukey test showed that the cement type, surface treatment method, and the interaction of these two factors significantly affect the shear bond strength between glass-ionomer cements and composite resin (p < 0.05). Surface treatment with phosphoric acid or Er,Cr:YSGG laser increased the shear bond strength of GIC to composite resin; however, in RMGIC only laser etching resulted in significantly higher bond strength. These findings were supported by SEM results. The fracture mode was evaluated under a stereomicroscope at ×20.  相似文献   
38.
The extent of agreement between subjects’ self-ratings on the Hopkins Symptom Checklist (HSCL) and physicians’ ratings on three other scales for emotional distress was examined in two nonpsychiatric groups–women attending a family-planning service and persons participating in a community health survey. Agreement between patient and physician assessments of depression and anxiety was high, and the HSCL proved to be accurate in identifying symptomatic patients. The findings support the value of the HSCL as a screening instrument for the detection of anxiety and depression in nonpsychiatric medical patients.  相似文献   
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40.
PURPOSE: To compare quality of life (QOL) and xerostomia between head-and-neck cancer patients who received standard radiotherapy (RT) and patients matched by factors known to affect QOL who received intensity-modulated RT (IMRT). METHODS AND MATERIALS: This was a prospective, longitudinal study of patients with head-and-neck cancer requiring bilateral neck irradiation who received IMRT at the University of Michigan and patients who received standard RT at affiliated clinics. Each patient received a validated head-and-neck cancer-related QOL questionnaire (HNQOL) consisting of four multi-item domains--Eating, Communication, Pain, and Emotion--and a validated patient-reported xerostomia questionnaire (XQ). In both questionnaires, the answers were scored 0-100, with higher scores denoting worse QOL or xerostomia. The questionnaires were given before therapy and at 1, 3, 6, 12, 18, and 24 months after the completion of therapy. Each standard RT patient was matched with several IMRT patients according to tumor site, stage, RT status (postoperative or definitive), and age. A linear mixed-effects model was fit to compare outcomes between the two treatment groups and to model trends over time. To account for matching, the differences in scores between the matched sets of patients were fit as a random intercept. Also, matching was taken into account in the model by using the standard error of the within-paired-groups differences. RESULTS: Between 1997 and 2002, 10 patients who had received standard RT and answered the XQ and HNQOL through at least 1 year were included in the study. Each of these patients was matched with a subgroup of 2-5 patients (median, 3) who had received IMRT, had similar patient and tumor characteristics, and answered the same questionnaires. A total of 30 patients were included in the IMRT group. During the initial months after therapy, the XQ and HNQOL summary scores worsened significantly in both groups compared with the pretherapy scores. Starting at 6 months, improvements of both XQ and HNQOL scores were found over time in the IMRT patients (p = 0.01 and 0.04, respectively), compared with no trend of improvement in the standard RT patients (p = 0.5 and 0.9, respectively). The trend of improvement over time in QOL in the IMRT patients was noted in most of the HNQOL domains (Eating: p = 0.07, Pain: p = 0.05, Emotion: p = 0.04, and Communication: p = 0.13), compared with no trend of improvement in most of the domains in the standard RT patients. As the scores of the IMRT (but not the standard RT) patients improved over time, the differences between the groups in the mean XQ and HNQOL summary scores widened. At 12 months, median XQ and HNQOL scores were lower (better) in the IMRT compared with the standard RT patients by 19 and 20 points, respectively, adjusted for the pretherapy values (p = 0.2). In both groups, the pretherapy XQ and HNQOL summary scores were significantly related to the respective posttherapy scores (p = 0.02 and p < 0.01, respectively). CONCLUSIONS: After initial posttherapy declines in both groups, xerostomia and QOL improved over time after IMRT but not after standard RT. The potential benefits gained from IMRT in xerostomia or in QOL, compared with standard RT, are best reflected late (> or = 6 months) after therapy.  相似文献   
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