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PURPOSE: To identify clinical characteristics associated with outcomes of treatment for persistent fetal vasculature (PFV based on a modified classification. METHODS: In this noncomparative case series, 54 eyes of 47 consecutive patients with PFV managed from 1981 until 1998 at a tertiary eye hospital were reviewed. Pars plicata lensectomy and vitrectomy was performed in 34 eyes and translimbal lensectomy and vitrectomy in five. Fifteen eyes were managed non-surgically. The following outcomes were measured: 1) "Visual improvement", defined as at least one Zipf's category improvement of best corrected final vision as compared with initial visual acuity, provided that final vision of CSUM (central, steady, unmaintained) equal to 20/100-20/30 was obtained. 2) "Cosmetic acceptability", defined as the absence of the following: small orbit, externally small appearing eye with microcornea and hypotony, eye deviation more than 35 prism diopters without strabismus surgery and corneal opacity. RESULTS: Six eyes were inoperable. In 10 out of 33 operated eyes (30.3%) improvement of vision was obtained including four eyes with an anterior form and six eyes with a combined form of PFV. In univariate analysis, factors such as anterior form of PFV surgery in the combined form and having a normal retina, had a weak association with a higher chance of visual improvement. In multivariate regression analysis the likelihood of unacceptable cosmetic appearance was higher in females than males (OR = 10.5), and in bilateral cases (OR = 7.9). Offspring of consanguineous marriages had more severe forms of PFV. CONCLUSIONS: Although visual potential is limited in PFV some eyes with an anterior or combined form and normal retina achieved improvement of visual acuity after surgery. However, statistically no single factor except sex and bilateral PFV (for cosmetic unacceptability) reliably predicted the results of treatment. Therapy should be individualized based on clinical findings. Genetic studies in offspring of consanguineous marriages with PFV may prove informative.  相似文献   
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The retinal synaptic network continues its development after birth in mammals. Recent studies show that postnatal development of retinal circuitry depends on visual stimulation. We sought to determine whether there is a time period during which the retina shows evidence of increased plasticity. We examined the effects of light deprivation on the retinal light response of mouse retina using electroretinogram (ERG) measurements. Our results showed that dark rearing mice from birth to postnatal day (P) 30, 60, and 90 suppressed the amplitudes of oscillatory potentials (OPs) and the magnitudes of suppression were age independent. In addition, dark-rearing-produced suppression of OP amplitudes can be completely reversed in both young and adult mice by returning them to cyclic light/dark conditions for 1 to 2 weeks. However, the recovery time course was age dependent with younger animals needing a longer time to achieve a full recovery. Furthermore, dark rearing of P60 mice raised under cyclic light/dark conditions for 30 days resulted in a similar magnitude of suppression of OP amplitudes as in age-matched mice dark reared from birth. These findings demonstrate that both the normal developmental changes and the maintenance of mature inner retinal light response in adult animals require visual stimulation. These results indicate a degree of activity-dependent plasticity in mouse retina that has not been previously described.  相似文献   
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The risky working environments of divers and pilots, and the possible role of extreme ambient pressure in carotid stenosis, make ischemic stroke an important occupational concern among these professionals. In this study, we aimed to evaluate the association of being exposed to hyperbaric or hypobaric conditions with carotid artery stenosis by comparing common carotid intima-media thickness (CCIMT) and blood flow velocities of cerebral arteries in divers and pilots using carotid duplex ultrasound (CDUS) and transcranial Doppler (TCD). CDUS and transtemporal TCD were performed in 29 divers, 36 pilots and 30 control participants. Medical history, blood pressure, lipid profile and blood sugar were recorded to control the previously well-known risk factors of atherosclerosis. Findings of the CDUS and TCD [including: CCIMT and blood flow velocities of internal carotid artery (ICA), common carotid artery (CCA), and middle cerebral artery (MCA)] of divers and pilots were compared with those of the control group using regression analysis models. Both right and left side CCIMT were significantly higher in divers (P < 0.05) and pilots (P < 0.05) in comparison with the control group. Carotid index [peak systolic velocity (PSV) of ICA/PSV of CCA) of divers and pilots were also higher than the control group. TCD findings were not significantly different between divers, pilots, and the control group. Increased CCIMT and carotid index in diver and pilot groups appear to be suggestive of accelerated atherosclerosis of carotid artery in these occupational groups.  相似文献   
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Transport of Ag(i), Cd(ii), Co(ii), Cu(ii), Ni(ii), Pb(ii) and Zn(ii) cations across a bulk liquid membrane (BLM) containing N,N′-dibenzyl-N′′-(2,2,2-trifluoroacetyl)-phosphoric triamide (PTC) as a new carrier is studied by atomic absorption spectrometry. The results show selective and efficient transport of the copper(ii) cation from aqueous solution in the presence of the other cations. Various factors are optimized in order to obtain maximum transport efficiency. The PTC ligand is characterized by single crystal X-ray diffraction analysis, IR, NMR (19F, 31P, 1H, 13C) and mass spectroscopy. The complex formation reaction between copper(ii) and PTC is studied by a conductometric method, which shows the 1 : 1 stoichiometry for ligand and copper(ii).

Selective transport of Cu(ii) cation in the presence of six other cations across a bulk liquid membrane containing a novel phosphoric triamide carrier is studied.  相似文献   
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Background  

Sternal wound infection (SWI) is an uncommon but potentially life-threatening complication of cardiac surgery. Predisposing factors for SWI are multiple with varied frequencies in different studies. The purpose of this study was to assess the incidence, risk factors, and mortality of SWI after coronary artery bypass grafting (CABG) at Tehran Heart Center.  相似文献   
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