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61.
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   
62.
Isolated dystonia of trunk and neck muscles without involvement elsewhere has been termed segmental axial dystonia--a rare disorder. We report a 31-year-old man who developed marked dystonia of paraspinal muscles and progressive scoliosis 6 months after a closed head injury. Computed tomography (CT) disclosed three small areas of encephalomalacia, one involving the head of the caudate nucleus. Treatment with trihexyphenidyl resulted in significant improvement of the dystonia and scoliosis.  相似文献   
63.
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   
64.
Objectives:The aim of this research was to assess galvanic behavior of lingual orthodontic brackets coupled with representative types of orthodontic wires.Materials and Methods:Three types of lingual brackets: Incognito (INC), In-Ovation L (IOV), and STb (STB) were combined with a stainless steel (SS) and a nickel-titanium (NiTi) orthodontic archwire. All materials were initially investigated by scanning electron microscopy / x-ray energy dispersive spectroscopy (SEM/EDX) while wires were also tested by x-ray diffraction spectroscopy (XRD). All bracket-wire combinations were immersed in acidic 0.1M NaCl 0.1M lactic acid and neutral NaF 0.3% (wt) electrolyte, and the potential differences were continuously recorded for 48 hours.Results:The SEM/EDX analysis revealed that INC is a single-unit bracket made of a high gold (Au) alloy while IOV and STB are two-piece appliances in which the base and wing are made of SS alloys. The SS wire demonstrated austenite and martensite iron phase, while NiTi wire illustrated an intense austenite crystallographic structure with limited martensite. All bracket wire combinations showed potential differences below the threshold of galvanic corrosion (200 mV) except for INC and STB coupled with NiTi wire in NaF media.Conclusions:The electrochemical results indicate that all brackets tested demonstrated galvanic compatibility with SS wire, but fluoride treatment should be used cautiously with NiTi wires coupled with Au and SS brackets.  相似文献   
65.
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   
66.
AIM: To determine the outcome of esophageal cancer patients referred for palliative care, in Gorgan and Gonbad gastrointestinal clinics, northeast of Iran.
METHODS: This cross-sectional study was done on inoperable esophageal cancer cases referred to gastrointestinal clinics in Gorgan and Gonbad city (2005-2006). Demographic data were collected during the procedure and cases were followed up every one month. Improvement proportion was calculated with 95% confidence interval, to determine the rate of improvement. Survival analysis and Kaplan- Meier methods were used to estimate the duration of palliative care effectiveness.
RESULTS: We recruited 39 cases into the study. Squamous cell carcinoma was the most prevalent (92.3%). The middle third of the esophagus was involved predominantly (51.3%). Dilation was the most preferred method (89.7%) and stenting was done in 4 cases. Decreasing dysphagia score was not related to palliation method or pathology type of carcinoma. Age of the patients was significantly related to the improvement of dysphagia score. Mean survival time was 137.6 d and median was 103 d.
CONCLUSION: Results of this study showed a low survival rate after palliative care in esophageal cancer cases despite dysphagia scores' improvement after dilating or stenting.  相似文献   
67.
Zika virus (ZIKV) was identified in 1947 in a rhesus monkey during an investigation of the yellow fever virus in the Zika Forest of Uganda; it was also isolated later from humans in Nigeria. The main distribution areas of ZIKV were the African mainland and South-East Asia in the 1980s, Micronesia in 2007, and more recently the Americas in 2014. ZIKV belongs to the Flaviviridae family and Flavivirus genus. ZIKV infection, which is transmitted by Aedes mosquitoes, is an emerging arbovirus disease. The clinical symptoms of ZIKV infection are fever, headache, rashes, arthralgia, and conjunctivitis, which clinically resemble dengue fever syndrome. Sometimes, ZIKV infection has been associated with Guillain-Barré syndrome and microcephaly. At the end of 2015, following an increase in cases of ZIKV infection associated with Guillain-Barré syndrome and microcephaly in newborns in Brazil, the World Health Organization declared a global emergency. Therefore, considering the global distribution and pathogenic nature of this virus, the current study aimed at reviewing the virologic features, transmission patterns, clinical manifestations, diagnosis, treatment, and prevention of ZIKV infection.  相似文献   
68.
Objective:To evaluate the combined effects of material type, surface treatment, and thermocycling on the bond strength of orthodontic brackets to materials used for the fabrication of provisional crowns.Materials and Methods:Four materials were included in this study (ProTemp, Trim Plus, Trim II, and Superpont C+B). Sixty cylindrical specimens (1 × 3 cm) were prepared from each material and equally divided into three groups. The first group was ground with silica carbide paper, the second was polished with pumice, and the last group was sandblasted with 50-µm aluminum oxide particles. Stainless-steel maxillary central incisor brackets (Victory Series, 3M) were bonded to the provisional material specimens with Transbond XT light-cured composite resin, and half of the specimens from each group were thermocycled 500 times in 5°C and 55°C water baths. Then the brackets were debonded with shear testing, and the results were statistically analyzed by three-way analysis of variance and Tukey''s multiple-comparison tests at α  =  0.05. Adhesive Remnant Index (ARI) was also identified.Results:Before and after thermocycling, ProTemp materials showed the highest shear bond strength with orthodontic brackets (10.3 and 13.1 MPa, respectively). The statistical analysis indicated an interaction among the three independent variables (P < .05) and statistically significant differences in bond strength among provisional materials (P < .001), surface treatments (P < .001), and thermocycling (P < .05). According to the ARI, most groups demonstrated adhesive failure.Conclusions:The provisional material type, surface treatment, and artificial aging have a significant effect on bond strength. Sandblasting treatment exerts a beneficial effect on shear bond strength.  相似文献   
69.
Miosis and internal ophthalmoplegia as a manifestation of partial seizures   总被引:1,自引:0,他引:1  
M L Rosenberg  B Jabbari 《Neurology》1991,41(5):737-739
We present a patient whose only physical manifestation of a partial sensory seizure was bilateral pupillary constriction and internal ophthalmoplegia. The onset and offset of each attack corresponded distinctly with an electroencephalographic discharge of the left temporo-occipital region. We propose involvement of a cortical pupillary constrictive center in the temporal-occipital area.  相似文献   
70.
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