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991.
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993.
Oncocytoma of the lacrimal sac is a rarely encountered clinical entity. We report the case of a 72-year-old female patient who was diagnosed to have bilateral nasolacrimal duct obstruction during a pre-cataract surgery screening. Subsequently, she underwent bilateral dacryocystectomy. Histopathological examination of the left lacrimal sac revealed a tumour composed of acini lined by oncocytic cells; features consistent with those of a lacrimal sac oncocytoma. Although rare, oncocytomas arising from the lacrimal sac may co-exist with a nasolacrimal duct obstruction. This report describes the histological and immunochemistry characteristics of oncocytomas and underscores the need to subject all excised lacrimal sacs to histopathological examination.  相似文献   
994.
995.
Measles remains an important cause of vaccine-preventable child mortality. Development of a low-cost, heat-stable vaccine for infants under the age of 6 months could improve measles control by facilitating delivery at the time of other vaccines and by closing a window of susceptibility prior to immunization at 9 months of age. DNA vaccines hold promise for development, but achieving protective levels of antibody has been difficult and there is an incomplete understanding of protective immunity. In the current study, we evaluated the use of a layered alphavirus DNA/RNA vector encoding measles virus H (SINCP-H) adsorbed onto polylactide glycolide (PLG) microparticles. In mice, antibody and T-cell responses to PLG-formulated DNA were substantially improved compared to those to naked DNA. Rhesus macaques received two doses of PLG/SINCP-H delivered either intramuscularly (0.5 mg) or intradermally (0.5 or 0.1 mg). Antibody and T-cell responses were induced but not sustained. On challenge, the intramuscularly vaccinated monkeys did not develop rashes and had lower viremias than vector-treated control monkeys. Monkeys vaccinated with the same dose intradermally developed rashes and viremia. Monkeys vaccinated intradermally with the low dose developed more severe rashes, with histopathologic evidence of syncytia and intense dermal and epidermal inflammation, eosinophilia, and higher viremia compared to vector-treated control monkeys. Protection after challenge correlated with gamma interferon-producing T cells and with early production of high-avidity antibody that bound wild-type H protein. We conclude that PLG/SINCP-H is most efficacious when delivered intramuscularly but does not provide an advantage over standard DNA vaccines for protection against measles.  相似文献   
996.
Solvent/non-solvent sintering creates porous polymeric microsphere scaffolds suitable for tissue engineering purposes with control over the resulting porosity, average pore diameter, and mechanical properties. Five different biodegradable biocompatible polyphosphazenes exhibiting glass transition temperatures from -8 to 41 degrees C and poly (lactide-co-glycolide), (PLAGA) a degradable polymer used in a number of biomedical settings, were examined to study the versatility of the process and benchmark the process to heat sintering. Parameters such as: solvent/non-solvent sintering solution composition and submersion time effect the sintering process. PLAGA microsphere scaffolds fabricated with solvent/non-solvent sintering exhibited an interconnected porosity and pore size of 31.9% and 179.1 mum, respectively which was analogous to that of conventional heat sintered PLAGA microsphere scaffolds. Biodegradable polyphosphazene microsphere scaffolds exhibited a maximum interconnected porosity of 37.6% and a maximum compressive modulus of 94.3 MPa. Solvent/non-solvent sintering is an effective strategy for sintering polymeric microspheres, with a broad spectrum of glass transition temperatures, under ambient conditions making it an excellent fabrication route for developing tissue engineering scaffolds and drug delivery vehicles.  相似文献   
997.
Accurate diagnosis of tuberculosis (TB) infection is critical for the treatment, prevention, and control of TB. Conventional diagnostic tests based on purified protein derivative (PPD) do not achieve the required diagnostic sensitivity. Therefore, in this study, we have evaluated the immunogenic properties of Rv1168c, a member of the PPE family, in comparison with PPD, which is routinely used in the tuberculin test, and Hsp60 and ESAT-6, well-known immunodominant antigens of Mycobacterium tuberculosis. In a conventional enzyme immunoassay, the recombinant Rv1168c protein displayed stronger immunoreactivity against the sera obtained from patients with clinically active TB than did PPD, Hsp60, or ESAT-6 and could distinguish TB patients from Mycobacterium bovis BCG-vaccinated controls. Interestingly, Rv1168c antigen permits diagnosis of smear-negative pulmonary TB as well as extrapulmonary TB cases, which are often difficult to diagnose by conventional tests. The immunodominant nature of Rv1168c makes it a promising candidate to use in serodiagnosis of TB. In addition, our studies also show that Rv1168c is a potent T-cell antigen which elicits a strong gamma interferon response in sensitized peripheral blood mononuclear cells obtained from TB patients.  相似文献   
998.

Background

Web-based programs for health promotion, disease prevention, and disease management often experience high rates of attrition. There are 3 questions which are particularly relevant to this issue. First, does engagement with program content predict long-term outcomes? Second, which users are most likely to drop out or disengage from the program? Third, do particular intervention strategies enhance engagement?

Objective

To determine: (1) whether engagement (defined by the number of Web sections opened) in a Web-based smoking cessation intervention predicts 6-month abstinence, (2) whether particular sociodemographic and psychographic groups are more likely to have lower engagement, and (3) whether particular components of a Web-based smoking cessation program influence engagement.

Methods

A randomized trial of 1866 smokers was used to examine the efficacy of 5 different treatment components of a Web-based smoking cessation intervention. The components were: high- versus low-personalized message source, high- versus low-tailored outcome expectation, efficacy expectation, and success story messages. Moreover, the timing of exposure to these sections was manipulated, with participants randomized to either a single unified Web program with all sections available at once, or sequential exposure to each section over a 5-week period of time. Participants from 2 large health plans enrolled to receive the online behavioral smoking cessation program and a free course of nicotine replacement therapy (patch). The program included: an introduction section, a section focusing on outcome expectations, 2 sections focusing on efficacy expectations, and a section with a narrative success story (5 sections altogether, each with multiple screens). Most of the analyses were conducted with a stratification of the 2 exposure types. Measures included: sociodemographic and psychosocial characteristics, Web sections opened, perceived message relevance, and smoking cessation 6-months following quit date.

Results

The total number of Web sections opened was related to subsequent smoking cessation. Participants who were younger, were male, or had less formal education were more likely to disengage from the Web-based cessation program, particularly when the program sections were delivered sequentially over time. More personalized source and high-depth tailored self-efficacy components were related to a greater number of Web sections opened. A path analysis model suggested that the impact of high-depth message tailoring on engagement in the sequentially delivered Web program was mediated by perceived message relevance.

Conclusions

Results of this study suggest that one of the mechanisms underlying the impact of Web-based smoking cessation interventions is engagement with the program. The source of the message, the degree of message tailoring, and the timing of exposure appear to influence Web-based program engagement.  相似文献   
999.
IntroductionThis study aims to assess the longer-term functional, anatomical, and metabolic outcomes of patients who underwent Studer neobladder (SNB) urinary diversion.MethodsA retrospective review of patients who underwent SNB at a single center from 1995–2017 (n=116) was performed. Demographics, comorbidities, pathological data, and longer-term functional, anatomical, and metabolic outcomes were collected from hospital records. The primary outcome was voiding function of patients at most recent followup. Secondary outcomes included postoperative complications, renal function, nephrolithiasis, infections, and metabolic outcomes.ResultsExcluding those with incomplete followup data, 72 patients with a minimum followup of one year were included for analysis. Median followup was 70±11 months, with 52.8% of patients having ≥5 years of followup. Clean intermittent catheterization (CIC) was used by 22.2% of patient at most recent followup, which was mostly necessitated by bladder overdistension, deteriorating renal function, or recurrent urosepsis despite timed voiding. Patients experienced more daytime and nighttime urinary incontinence in the early postoperative setting, which improved over time. Generally, renal function declined over time; poorer long-term renal function was predicted by hydronephrosis within one year (p=0.002).ConclusionsLonger-term followup of SNB reveals significant but manageable complications. Gradual decline in renal function was common. Strict adherence to bladder emptying protocols (e.g., timed voiding or CIC) may reduce incidence of renal deterioration, metabolic disorders, and urinary dysfunction. Early onset (<1 year) of hydronephrosis may indicate a need for intervention to preserve long-term renal function.  相似文献   
1000.
Arterial aneurysms have only recently been associated with the human immunodeficiency virus (HIV). The clinical and pathological features of 10 HIV-positive patients with arterial aneurysms were retrospectively evaluated. These aneurysms were unusual in that they affected young black patients, occurred in atypical sites, and tended toward multiplicity. Surgery was performed in eight patients. Acute and chronic inflammatory changes were revealed by means of histologic examination of the aneurysm walls, with occlusion of the vasa vasora by inflammatory infiltrate or edema being a prominent feature. Culture of the aneurysm wall or thrombus yielded positive results in two patients. The association between HIV and aneurysms may be coincidental, caused by direct viral action or by bacterial infection resulting from immunosuppression. Implications for therapy are discussed, and the need for further study is highlighted.  相似文献   
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