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71.
MP Richardson TJ Williamson SW Lenton MJ Tarlow PT Rudd 《Archives of disease in childhood》1995,72(4):294-297
Transient evoked otoacoustic emissions (TEOAEs) are low amplitude sound waves produced by the healthy cochlea. They can be recorded with a microphone in the external ear. TEOAEs are abolished by hearing losses of 30 dB or more. The feasibility of using TEOAEs as a screening test for hearing loss in children was studied. TEOAE recordings were attempted in 56 children attending an audiology clinic. Recordings were possible from both ears in 52 children; of these 104 ears, 32 had hearing deficits of 30 dB or more. Hearing status was compared with the results of six TEOAE screening criteria. All criteria had a sensitivity of 1.00. Four standard TEOAE criteria yielded specificities of 0.46-0.58. Two new criteria derived from analysis of limited frequencies from the TEOAE waveform gave specificities of 0.76 and 0.82. It can be concluded that, when appropriate pass/fail criteria are employed, TEOAEs are a feasible screening test in children. 相似文献
72.
Objective: To ascertain blood lead levels in a sample of preschool children from Fremantle, Western Australia, and to correlate these with possible risk factors.
Methodology The study was a cross-sectional prevalence survey of 120 children from day-care centres and 44 hospital inpatients. Blood lead and ferritin levels were determined and a risk factor questionnaire was completed by parents.
Results Of the 164 children 25.6% had lead levels above the NH&MRC goal (<10μg/dL). Nine of 133 (6.7%) had ferritin levels below 10 μg/L suggesting iron deficiency. Excessive blood lead concentrations as defined by the NH&MRC (>9μg/dL) related to: child's presence during house renovation (OR 3.35, P = 0.007, 95% Cl 1.39-8.81); Aboriginality (OR 6.4, P = 0.008, 95% Cl 1.6-24.9), and, in the 9-24 month age group, inversely to distance between home and a road carrying >7000 vehicles/day (r-0.56, P = 0.009, n = 24).
Conclusions A group of Fremantle children with unacceptably high blood lead levels has been identified. Renovation of older housing and Aboriginality are important risk factors. 相似文献
Methodology The study was a cross-sectional prevalence survey of 120 children from day-care centres and 44 hospital inpatients. Blood lead and ferritin levels were determined and a risk factor questionnaire was completed by parents.
Results Of the 164 children 25.6% had lead levels above the NH&MRC goal (<10μg/dL). Nine of 133 (6.7%) had ferritin levels below 10 μg/L suggesting iron deficiency. Excessive blood lead concentrations as defined by the NH&MRC (>9μg/dL) related to: child's presence during house renovation (OR 3.35, P = 0.007, 95% Cl 1.39-8.81); Aboriginality (OR 6.4, P = 0.008, 95% Cl 1.6-24.9), and, in the 9-24 month age group, inversely to distance between home and a road carrying >7000 vehicles/day (r-0.56, P = 0.009, n = 24).
Conclusions A group of Fremantle children with unacceptably high blood lead levels has been identified. Renovation of older housing and Aboriginality are important risk factors. 相似文献
73.
74.
Ayala Espinosa MJ Pérez-Santonja JJ Alió Y Sanz JL Artola Roig A Cardona Ausina C 《Archivos de la Sociedad Espa?ola de Oftalmología》2000,75(12):835-837
CASE REPORT: We present a case of traumatic displacement of corneal flap in the superior temporal quadrant 13 days after LASIK. The flap was repositioned after gentle irrigation of BSS, cleaned the interface and then drying the flap to verify its stability. In the next day the flap was adhered, clear cornea,smooth and visual acuity without correction was 1.00. DISCUSSION: We should try immediately to reposition the flap after traumatic displacement, as in this case. 相似文献
75.
Pickles T Agranovich A Berthelet E Duncan GG Keyes M Kwan W McKenzie MR Morris WJ;British Columbia Cancer Agency Prostate Cohort Outcomes Initiative 《Cancer》2002,94(2):362-367
BACKGROUND: This study was conducted to describe the rate and completeness of the recovery of testosterone production following prolonged temporary androgen ablative therapy in men with prostate carcinoma undergoing curative radiation therapy. METHODS: Two-hundred and sixty-seven men treated with between 3 months and 3 years of adjuvant androgen ablation (AA) were followed at 6-month intervals following cessation of their androgen deprivation therapy. A comparative group of 518 men not undergoing AA were also followed. RESULTS: Drugs used included low dose cyproterone/stilboestrol (CPA/DES) in combination (56%) and 1 month depot (18%) and 3 month depot (25%) leutinizing hormone releasing hormone agonist (LHRHa). Seventy-nine percent of men in the current study recovered normal testosterone levels (10nmol/L), and 93% recovered levels of at least 5nmol/L. In comparison, men who had never received androgen ablative therapy showed a fall of testosterone, with 17% having sub-normal levels after 3 years. Median time to testosterone recovery was 10 months. Factors associated on multivariate analysis with delayed testosterone recovery included advanced age (P = 0.008), low pre-therapy testosterone (P = 0.04), and the use of 3 month LHRHa preparations as compared with CPA/DES (P = 0.002) or 1 month LHRHa preparations (P = 0.015). The duration of drug use was not significantly associated with time to testosterone recovery. CONCLUSIONS: Long-acting LHRHa preparations appear to have a more prolonged action than previously supposed. Most men treated for up to 2 years recover normal testosterone levels after cessation of adjuvant androgen ablation, and the limited data available in the current study on patients treated for 3 years also suggests most will recover. 相似文献
76.
77.
MJ Veness F Foroudi V Gebski I Timms Y Sathiyaseelan B Cakir KW Tiver 《Journal of Medical Imaging and Radiation Oncology》2006,50(5):468-474
Radiation‐induced mucositis is an acute reaction of the mucosa of patients undergoing head and neck radiotherapy. It can have debilitating and dose‐limiting consequences. There is no consensus on an accepted intervention that significantly reduces its severity. Misoprostol is a synthetic prostaglandin E1 analogue, with properties of a mucosal cytoprotectant. We designed a randomized, double‐blind, placebo‐controlled trial of misoprostol in patients with head and neck cancer. The aim of this study was to determine if topical misoprostol was effective in reducing the severity of radiation‐induced mucositis in patients receiving radical dose radiotherapy. The effect of this intervention on a patient’s general well‐being was also investigated. The primary end‐point of the study was the incidence of Radiation Therapy Oncology Group grade 3 mucositis. Between 1999 and 2002, 83 patients were recruited into the study at Westmead and Nepean Hospitals, Sydney. Forty‐two patients were randomized to receive misoprostol and 41 to receive a placebo. Most patients received radiotherapy in the adjuvant setting (52 of the 83) and had either an oral cavity (42 of the 83) or an oropharyngeal (16 of the 83) cancer. We could not identify any significant difference in the incidence of severe mucositis based on whether patients were allocated to receive misoprostol or placebo. There was no significant difference in the mean area under the mucositis curve (13.2 vs 16.6; P = 0.1). Patients allocated to misoprostol did report slightly increased soreness (7.6 vs 6.9; P = 0.04) and a greater use of analgesics. However, this difference did not translate into a worse feeling of general well‐being as measured by a simple visual analogue scale (5.8 vs 5.2; P = 0.3). In conclusion, we were unable to identify a reduction in radiation‐induced mucositis in patients receiving misoprostol. There is a paucity of high‐level evidence on potentially useful interventions and a continued need for new and innovative research, incorporating quality‐of‐life measurements, in patients experiencing radiation‐induced mucositis. 相似文献
78.
GM Thambugala A Mohamed GFA O Neill MJ Fulham 《Journal of Medical Imaging and Radiation Oncology》2006,50(6):604-606
We present the FDG PET‐CT findings in a patient with persistent pain 7 weeks after a nephrectomy and lymph node dissection for a sarcomatoid renal cell carcinoma. Although conventional imaging was unable to detect evidence of metastatic spread outside the para‐aortic nodes, a PET‐CT scan showed unexpected extensive dissemination. Currently, there are no reports in the literature of the PET‐CT findings in sarcomatoid renal cell carcinomas. 相似文献
79.
A striking difference between two structurally related anti-estrogen
medicines is that tamoxifen is strongly hepatocarcinogenic in the rat,
whereas toremifene lacks such activity. To study the basis for this
difference, the initiating potential of tamoxifen and toremifene were
studied by measurement of rapid induction of hepatocellular altered foci
(HAF) that express placental-type glutathione S-transferase in the livers
of female Sprague-Dawley (S-D) rats and female Fischer 344 (F344) rats.
Both agents were administered by gavage at equimolar doses up to a dose
that produced marked weight gain suppression. In rats given the high dose
of 40 mg/kg per day tamoxifen continuously for 36 weeks, 75% of S-D rats
developed liver neoplasms, in contrast to only 10% of F344 rats. In the S-D
strain, tamoxifen produced a tendency to increased HAF at 2 weeks at the
dose of 40 mg/kg per day and by 12 weeks, a dose-related increase was
evident. In contrast, toremifene induced no HAF even at the equimolar high
dose of 42.4 mg/kg per day for 12 weeks. The induction of HAF by tamoxifen
was less in the F344 rats. Neither agent elicited increases in
hepatocellular proliferation in S-D or F344 rats. When phenobarbital was
administered for 24 weeks as a promoting agent after the anti-estrogens,
S-D rats given tamoxifen at 20 mg/kg per day for 12 weeks, developed liver
neoplasms, but not F344 rats or rats of either strain given even a higher
dose (42.4 mg/kg) of toremifene. Thus, tamoxifen has initiating activity in
these rat strains whereas toremifene does not.
相似文献
80.
The Syrian hamster embryo (SHE) cell system was used to evaluate the
ability of two hepatocarcinogenic structurally related peroxisome
proliferators (PPs) to induce morphological transformation (MT) of SHE
colonies and to inhibit gap junctional intercellular communication (GJIC).
Clofibrate and methyl clofenapate (MCP), which was shown to be a more
active PP and a more potent carcinogen in vivo than clofibrate, were
compared. MCP appeared slightly more active in vitro than clofibrate in
affecting MT and GJIC of SHE cells. The morphological transformation of SHE
colonies was induced by 50 microM MCP, against 100 microM clofibrate.
Moreover, 50 microM MCP potentiated the transforming effects of both
benzo[a]pyrene and 12-O- tetradecanoylphorbol-13-acetate. The inhibition of
GJIC, measured by transfer of lucifer yellow, was transient and occurred at
concentrations inducing morphological transformation. MCP inhibited dye
transfer at 50 microM and the inhibition lasted up to 24 h at 100 microM.
Inhibition of communication lasted only 4 h with clofibrate and occurred at
a higher concentration (175 microM). This study showed that both the SHE
cell transformation and dye transfer assays were able to display the
different activities of the two PPs, even though the difference in potency
observed was smaller than in vivo. It also revealed interactions between
non-genotoxic carcinogens and the ability of the SHE cell transformation
assay to detect these combined effects.
相似文献