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1.
We studied retrospectively 12 eyes with a solitary choroidal hemangioma in 12 patients over a period of 13 years. A peculiar, even hyperfluorescence of the tumor within the retinal venous phases occurred in all 12 cases. In all but four patients, laser therapy was performed to reduce subretinal fluid and partially destroy the tumor. Two of the three eyes without extensive retinal detachment or cystoid macular edema at the initial visit regained a final vision of 20/30 or better. The remaining 5 patients with the two major complications had a final vision of 20/80 or worse due to degenerative retinal changes. We believe that laser treatment is definitely advisable in the early stages of a circumscribed choroidal hemangioma.The study was performed at the Institute of Ophthalmology, University of Nijmegen.  相似文献   
2.
The surface-induced mineralization (SIM) technique was used to produce hydroxyapatite (HAP) coatings on external fixation pins with the antimicrobial agent, chlorhexidine, incorporated within the coating. The SIM process involved surface modification of the substrate with organic functional groups followed by immersion in aqueous supersaturated calcium phosphate solutions. X-ray diffraction spectra confirmed that hydroxyapatite coatings were formed. Chlorhexidine was incorporated into the coating by placing the substrate into various chlorhexidine solutions in between mineralization cycles. Total uptake was measured by dissolution of the coating into a 0.1 M nitric acid solution and measuring the chlorhexidine concentration using UV spectroscopy at 251 nm. Release rates were measured by submersion of coated substrates into saline solutions and measuring chlorhexidine UV absorbency at 231 nm as a function of time. Results show an initial rapid release followed by a period of slower sustained release. The anti-microbial efficacy of the HAP-chlorhexidine coatings was evaluated in vitro using a Staphylococcus aureus cell culture. Initial results show a large "inhibition zone" formed around the chlorhexidine/HAP coating vs. coatings with HAP only. This preliminary work clearly demonstrates that SIM HAP coatings have great potential to locally deliver antimicrobial agents such as chlorhexidine at implantation sites, which may greatly reduce the incidence of pin tract infection that occurs in external fixation.  相似文献   
3.
Paget's disease is usually associated with an underlying adenocarcinoma of the breast. The initial manifestation is an eczematous or psoriasiform lesion of the nipple, soon extending to the mammary areola and then to the surrounding skin. The histology of the lesions is characterized by the presence, within the epidermal layer, of the so-called Paget's cells, i.e. large cells with vesicular nucleus and clear cytoplasm. The authors report a recent case of Paget's disease of the breast in a 75-year-old woman, unusual both for clinical course and observed histology. As for the clinico-evolutive aspects, although in the case observed the initial skin lesions appeared 20 years before, the different diagnostic procedures repeatedly performed showed no evidence in this patient of an underlying adenocarcinoma. The histologic aspect, on the other hand, was peculiar since the typical characteristics of an acantholytic disease were evident. The presence of intraepidermal cleavages with lost, at times, of the normal contacts among the cells of the Malpighian layer has been described only once in Paget's disease. This fact caused some diagnostic difficulties: however, the typical finding of the Paget cells, their positivity to histochemical methods such as cytokeratin and acid phosphatase allowed the diagnosis. The authors, at last, evaluate the need of a surgical therapy in Paget's disease of the breast without an underlying adenocarcinoma.  相似文献   
4.
Scleroderma is a connective tissue disease with a variety of clinical presentations. The purpose of our study was to review representative cases of scleroderma in childhood to determine the initial presentation, course of the disease, orthopaedic manifestations, and the necessity and success of surgical intervention. Records from the four medical centers were retrospectively reviewed to identify the patients who were diagnosed with scleroderma over the past 35 years. Data on disease presentation, course, treatment, and response were collected. Seventeen cases representing the variety of clinical presentations are presented. Scleroderma characteristically presents with asymmetric lesions involving the extremities and remains a diagnostic and therapeutic challenge. Treatment must be individualized to the patient and his or her specific limitations brought about by the disease. Early diagnosis, supportive care, and physical therapy combined with early orthopaedic surgical intervention to release joint contractures are among the most efficacious treatments.  相似文献   
5.
A 1H and 13C NMR study on the inclusion complex of paroxetine with β-cyclodextrin was carried out in order to define the stoichiometry of the association and its strength. Proton and carbon chemical shift measurements of paroxetine and β-cyclodextrin were performed at several molar ratios and temperatures, allowing the determination of a 1:1 stoichiometry and an association constant value of the order of 2 × 103 for the paroxetine–β-cyclodextrin complex. Overhauser effects in the rotating frame were also measured, and the experimental interproton distance constraints have been used for molecular model building of the complex. The obtained model indicates that the benzodioxolyl moiety of paroxetine is deeply inserted in the cavity of the cylindrical structure of β-cyclodextrin, while the fluoro-phenyl ring lays above the wider rim.  相似文献   
6.
Medullary thyroid carcinoma (MTC) is a rare tumor originating from thyroid parafollicular C cells, where, in the inherited form, constitutive activation of the RET protooncogene is responsible for unrestrained cell proliferation. We previously demonstrated that somatostatin (SRIF) reduces cell growth in the human MTC cell line TT, which expresses all SRIF receptor (SSTR) subtypes and responds differently to selective SSTR agonists. The antiproliferative mechanism of SRIF and its analogs in MTC is still unclear. Src homology-2-containing protein tyrosine phosphatase-1 (SHP-1), a cytoplasmic protein tyrosine phosphatase (PTP), is activated by somatotropin release-inhibiting factor and reduces mutated RET autophosphorylation in a heterologous system. In this study, we explore the role of PTP activation, in particular of SHP-1, in TT cells, where RET is constitutively activated. In TT cells, SRIF stimulated the PTP activity of SHP-1, which was associated with proliferation inhibition and with reduction in the MAPK pathway activation. Blockade of PTP activity with sodium orthovanadate induced cell proliferation and MAPK phosphorylation and blunted the inhibitory effects of SRIF. Moreover, SHP-1 associates with SSTR2 depending on its activation. By using a MAPK kinase inhibitor, we demonstrated that TT cell growth depends on MAPK pathway activation. Furthermore, in TT cells overexpressing SHP-1, cell proliferation and MAPK signaling were strongly down-regulated, whereas in TT cells transfected with a dominant negative form of SHP-1, cell proliferation and MAPK signaling were markedly induced. Our data demonstrate that SRIF inhibitory effects on TT cell proliferation are mediated, at least in part, by SHP-1, which acts through a MAPK-dependent mechanism.  相似文献   
7.
We assessed the effects of left ventricular pacing on echocardiographic and clinical parameters in 13 consecutive patients with heart failure and bundle branch block by means of a controlled acute and medium-term evaluation. Left ventricular pacing induced a significant improvement in left ventricular ejection fraction, Minnesota Living with Heart Failure Questionnaire score, New York Heart Association class, and 6-minute walking test compared with sinus rhythm or right ventricular pacing.  相似文献   
8.
Journal of Neurology - In Italy, lockdown due to COVID-19 health emergency started on March 10 and partially ended on May 3rd, 2020. There was a significant increase of psychological distress and...  相似文献   
9.
BackgroundProprioception has been defined as the capacity to feel the position of a joint in space as sensed by the central nervous system. Prophylactic knee braces are supposed to help in knee injury prevention not just with a mechanical support of the joint but also improving proprioception. The main aim of this study was to determine the effects of a knee brace and a knee sleeve on knee proprioception. The secondary aim was to determine if different starting angles of the knee and different movement directions influence knee proprioception.MethodsWe tested a group of twenty healthy male sport students without knee injuries. They were tested with the brace, with the sleeve and without support. The threshold of detection of passive knee movement with a starting knee angle of 30° and 60°, both in flexion and extension was determined.ResultsWe did not find any statistically significant change in the threshold of detection of passive knee movement wearing the brace or the sleeve compared to the unsupported condition (p = 0.462, α = 0.05). We found a significantly lower proprioceptive sensitivity starting at the more flexed knee angle (p = 0.005, α = 0.05) and moving in extension than in the other test situations (p = 0.001, α = 0.05).ConclusionMovement direction and starting position appear to influence the threshold of detection of passive knee movement. The results of this study also suggest that knee supports do not influence either positively or negatively knee proprioception of uninjured active subjects.  相似文献   
10.
Two new natural CphA metallo-β-lactamases, the CphA4 and CphA5 enzymes, were identified in water samples from municipal sewage in central Italy. Compared to CphA, the CphA4 and CphA5 enzymes showed numerous point mutations. These enzymes have a narrow spectrum of substrates focused on carbapenems only. CphA5 showed kcat values about 40-, 12-, and 97-fold higher than those observed for CphA4 versus imipenem, ertapenem, and biapenem, respectively.  相似文献   
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