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31.
The desirable mechanical properties of nickel-titanium alloy wires and their relatively high cost has prompted many clinicians to recycle these wires. Clinical recycling exposes the wires to several weeks or months of mechanical stresses and elements of the oral environment, as well as sterilization between uses. In a previous study it was noted that clinical recycling combined with cold sterilization alters the load-deflection characteristics and surface topography of nickel-titanium wires. Whether similar changes in mechanical properties occur in wires subjected to repeated clinical use and dry heat sterilization is not yet clear. The purpose of this investigation was to determine the effects of in vivo recycling interposed by dry heat sterilization (together referred to as clinical recycling, CR) on the load-deflection characteristics of nickel-titanium alloy wires. To differentiate the effects of dry heat sterilization (DHS) from those of CR on the behavior of these wires, a series of wires were also subjected to DHS only. Two types of nickel-titanium wires, namely Nitinol and NiTi were subjected to a three-point bending test in an as-received condition (T0), after one cycle (T1), and two cycles (T2) of DHS or CR. Ten wires comprised each subsample. Statistical analyses were done by one-factor repeated measures analysis of variance and Scheffe F test. Both DHS alone, as well as CR, produced significant changes in the loading and unloading characteristics of Nitinol and NiTi wires. However, the changes in the load-deflection characteristics of these wires after DHS only were relatively small, and the clinical significance of these changes is open to question.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Septicemia due to Pseudomonas putrefaciens was found in an elderly man with chronic leg ulcers. This organism is rarely cultured from human material and has been reported to cause skin and ear infections in only a few patients. Its potential for invasiveness is documented in this case for the fourth time.  相似文献   
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The clinicopathological profile of 7 cases of Cryptococcal meningitis encountered over one year period in a military hospital has been described. Severe persistent headache was the main form of presentation followed by features of progressive ill-health. Age range of cases was 34–55 years (mean 40.8 years). All were males and 6 were serving soldiers. Duration of symptoms ranged from 10 days to 6 weeks. Six patients were positive for HIV-1 antibodies. This was the initial presentation of AIDS in 6 patients accounting for 10.34% among all cases of HIV infection during that year. Both clinical and laboratory findings were subtle. Nuchal rigidity was rare, cerebro spinal fluid (CSF) cell count and protein level was normal in 3 out of 7 cases. Although culture for Cryptococcus was positive in all, it took 10 days to grow in 2 cases. India-ink stain showed scanty number of organisms in 3 cases. Low cell counts in CSF and presence of associated hyponatremia appear to be bad prognostic indicators in Cryptococcal infections of central nervous system. Latex agglutination test is a worthwhile screening test.Key Words: Cryptococcal meningitis, Cryptococcus neoformans, Opportunistic infection  相似文献   
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Access to safe breast-feeding alternatives for HIV-infected mothers and their infants in many settings is limited. We compared the rates of early postpartum hospitalization of infants born to HIV-infected mothers using different infant-feeding practices in a large government hospital in Pune, India. From March 1, 2000 to November 30, 2001, infants born to HIV-infected mothers were followed in a postpartum clinic. All mothers had received a standard short course of antenatal zidovudine. Infant-feeding practices were assessed within 3 d of delivery, prior to postpartum hospital discharge. Sixty-two of 148 mothers (42%) were breast-feeding their infants. Eighty-six of the mothers (58%) were providing replacement feeding, primarily diluted cow, goat or buffalo milk (top feeding). Twenty-one of the 148 participating infants (14.2%) born during the study period required hospitalization within the 1st 6 mo of life and 6 infants required repeat hospitalization. All hospitalized infants were receiving replacement feeding with a rate of 0.093 hospitalizations per 100 person-days (95% CI, 0.062 to 0.136). The reasons for hospitalization included acute gastroenteritis (48.1%), pneumonia (18.5%), septicemia (11.1%) and jaundice (11.1%). A high risk for early postpartum hospitalization was seen in replacement-fed infants born to HIV-infected mothers in Pune, India. In settings such as India, where access to safe replacement feeding is limited, interventions making exclusive breast-feeding safer for HIV-infected mothers and infants are needed. Such interventions would be valuable additions to the very effective national prevention programs that currently rely on the provision of short-course zidovudine and nevirapine.  相似文献   
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Thirteen children, ranging in age from 45 days to 2 years, had severe gastrointestinal illness with the features characteristic of neonatal necrotising enterocolitis. All 13 children had preceding gastroenteritis leading to hypovolaemia. Necrotising enterocolitis can occur in children beyond the neonatal age group and it may occur as a sequel to gastroenteritis.  相似文献   
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BACKGROUND: The diagnosis of progressing periodontal disease typically relies on retrospective methods that detect changes in the amount of periodontal breakdown. Fibronectin (FN) fragments are found in vivo in association with periodontal disease, and specific FN fragments compromise periodontal ligament cell functions in vitro. The overall goal of this cross-sectional study was to determine whether specific FN fragments are present in gingival crevicular fluid (GCF) and can be used as markers for periodontal disease status. The eventual goal is to test these FN fragments in a longitudinal study as potential markers of disease activity. METHODS: GCF was collected from 94 subjects with untreated periodontitis from clinically healthy, mild/moderate periodontitis, and severe periodontitis sites. Sites were defined on the basis of clinical criteria, including gingival bleeding index, probing depth, and clinical attachment level. Western immunoblotting was used to detect FN fragments in GCF using antibodies to specific FN domains, including the collagen/gelatin-, central cell-, and carboxyl terminal heparin-binding domains, plus the CS-1 site on the alternatively spliced V region and the EIIIA region. FN fragments identified by immunoblotting and analyzed by NIH image software were scored based on pixel intensity and an ordinal grade scale. RESULTS: We identified several fragments highly associated with severe periodontitis sites, including 40-kDa, 120-kDa, and 68-kDa fragments. Conclusions: This study demonstrates that specific FN fragments are markers for periodontal disease status and supports the role of FN fragments as potential components in the pathogenesis of periodontal disease.  相似文献   
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