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81.
Bradfield YS Plager DA Neely DE Sprunger DT Sondhi N 《Journal of cataract and refractive surgery》2004,30(9):1948-1952
PURPOSE: To investigate the magnitude of postoperative astigmatism in children having cataract extraction with intraocular lens (IOL) implantation through a 3.0 mm superior clear corneal incision. SETTING: Department of Ophthalmology, Indiana University School of Medicine, Indianapolis, Indiana, USA. METHODS: This retrospective chart review comprised all pediatric patients having cataract surgery with IOL implantation through a 3.0 mm clear corneal incision from 1997 to 2002. One hundred two eyes of 75 patients were included. All refractions were performed manually by an experienced pediatric ophthalmologist. RESULTS: The mean postoperative retinoscopic cylinder in all patients was 0.63 diopter (D) (range 0.0 to 4.50 D) at 1 month, 0.40 D (range 0.0 to 1.75 D) at 6 months, and 0.51 D (range 0.0 to 2.50 D) at 1 year. Patients aged 0 to 36 months at the time of surgery had a mean postoperative cylinder of 0.22 D at 1 month, 0.03 D at 6 months, and 0.21 D at 1 year. Patients between 36 months and 6 years of age at surgery had a mean refractive cylinder of 0.50 D, 0.38 D, and 0.75 D, respectively. Patients older than 6 years at surgery had a mean refractive cylinder of 0.94 D, 0.75 D, and 0.76 D, respectively. CONCLUSIONS: Small-incision clear corneal cataract extraction with IOL implantation in children led to minimal postoperative astigmatism that remained stable over time. Less astigmatism was observed in children having surgery before they were 36 months old. 相似文献
82.
Two simple and sensitive validated spectrophotometric methods have been described for the assay of nicorandil in drug formulations. Method A is based on the reaction of the drug with phloroglucinol-sulfanilic acid reagent in sulfuric acid medium to give yellow-colored product, which absorbs maximally at 425 nm. Method B uses the oxidative coupling of 3-methyl-2-benzothiazolinone hydrazone hydrochloride (MBTH) with DL- 3,4 - dihydroxyphenylalanine (DL-dopa) in the presence of nicorandil as oxidant in sulfuric acid medium to form an intensely colored product having maximum absorbance at 530 nm. Beer's law is obeyed in the concentration range 2.5 to 50.0 and 1.0 to 15.0 microg mL(-1) with methods A and B, respectively. Both methods have been successfully applied for the analysis of drug in pharmaceutical formulations. The reliability and the performance of the proposed methods are established by point and interval hypothesis and through recovery studies. The experimental true bias of all samples is smaller than +/-2%. 相似文献
83.
84.
Neutropenic patients who continue to be febrile despite adequate broad-spectrum antibacterial treatment require empirical antifungal therapy. The aim of the present study was to evaluate the safety and efficacy of oral fluconazole for empirical antifungal therapy in neutropenic patients with persistent fever. A prospective cohort design was used. The study sample included 250 consecutive patients with high-risk stage II, III, or responding metastatic breast cancer who received high-dose chemotherapy (HDC) with autologous peripheral blood progenitor stem cell transplantation. Those with neutropenic fever lasting more than 72 hours despite broad-spectrum antibacterial coverage were treated with fluconazole. Treatment was continued until fever dropped and/or neutrophil count recovered with blood cultures remaining negative. Antifungal treatment was required in 173 patients (69%). There were no cases of documented deep systemic fungal infection. Two patients (<1%) had positive blood cultures for fungi. None of the patients experienced toxicity related to fluconazole. There was one transplant-related death. Thirty-one patients (18%) were unable to complete the oral fluconazole protocol because of severe mucositis, and they received intravenous fluconazole at the same dose, with similar efficacy. Oral fluconazole is a safe and effective alternative to amphotericin B for empirical early antifungal treatment in persistent neutropenic fever in breast cancer patients undergoing HDC with autologous stem cell support. Further study of oral fluconazole and amphotericin B as empirical agents in other groups of patients with persistent neutropenic fever is warranted. 相似文献
85.
Vitamin D requirements are thought to vary with age, but there is little comparative evidence for this. One goal in establishing a vitamin D requirement is to avoid secondary hyperparathyroidism. We studied 1741 euthyroid, thyroid clinic outpatients without evidence of calcium abnormalities, ranging in age from 19 to 97 yr, whose serum and urine had been analyzed for calcium, vitamin D, and parathyroid status. We found no effect of age on the 25-hydroxyvitamin D [25(OH)D] concentration associated with specific vitamin D intakes, and there was no relationship between 25(OH)D and 1,25hydroxyvitamin D [1,25(OH)2D]. In every age group, serum 1,25(OH)2D declined with increasing creatinine (P < 0.001). What changed with age included creatinine, which correlated with 25(OH)D (r = 0.146, P < 0.001) only in the youngest age group (19-50 yr) but not in the older age groups (P > 0.1). Creatinine did not correlate with PTH in the youngest age group, but the relationship became significant as age increased (e.g. for the elderly, r = 0.365, P < 0.001). Linear regression of log PTH vs. log 25(OH)D agreed with the natural shape of the relationship observed with scatterplot smoothing, and this showed no plateau in PTH as 25(OH)D increased. We compared PTH concentrations among age groups, based on 20 nmol/liter increments in 25(OH)D. Mean PTH in adults older than 70 yr was consistently higher than in adults younger than 50 yr (P < 0.05 by ANOVA and Dunnett's t test). PTH levels of the elderly who had 25(OH)D concentrations greater than 100 nmol/liter matched PTH of younger adults having 25(OH)D concentrations near 70 nmol/liter. This study shows that all age groups exhibit a high prevalence of 25(OH)D insufficiency and secondary hyperparathyroidism. Older adults are just as efficient in maintaining 25(OH)D, but they need more vitamin D to produce the higher 25(OH)D concentrations required to overcome the hyperparathyroidism associated with their diminishing renal function. 相似文献
86.
Effects of simvastatin on bone regeneration in the mandibles of ovariectomized rats and on blood cholesterol levels 总被引:1,自引:0,他引:1
Junqueira JC Mancini MN Carvalho YR Anbinder AL Balducci I Rocha RF 《Journal of Oral Science》2002,44(3-4):117-124
The purpose of this study was to evaluate the effects of simvastatin on guided bone regeneration in the mandibles of ovariectomized rats, and to observe their blood cholesterol levels. Seventy female rats were divided into two groups: control and treated, both groups containing normal and ovariectomized rats. A month after ovariectomy a bone defect was created in the mandible, and was covered by a polytetrafluoroethylene membrane. The treated groups received simvastatin orally for 15 or 30 days. The rats were sacrificed 15, 30 or 60 days after surgery, at which time a blood sample was extracted for blood cholesterol level analysis and the mandible was extracted for densitometric, histological and morphometric analysis. All specimens underwent analysis of variance. The ovariectomized animals had higher cholesterol levels than the treated normal animals, and no significant difference was found between the different treatment periods and the sacrifice times. The densitometric, histological and morphometric analysis showed that the treated ovariectomized animals developed more new bone than the control ovariectomized rats, but no significant difference was observed between the treatment periods. It can be concluded that the deficiency of estrogen increased the level of blood cholesterol and that the simvastatin aided new bone formation in the ovariectomized animals. 相似文献
87.
OBJECTIVE: Our objectives were to describe the characteristics of "mixed practices"-that is, practices performing both diagnostic radiology and radiation oncology services-and to compare mixed practices with multiradiologist diagnostic radiology-only practices. MATERIALS AND METHODS: In 1999, the American College of Radiology surveyed 970 practices by mail, using a 65-item questionnaire. A response rate of 66% was achieved. Responses were weighted such that they were representative of all the radiology practices in the United States. The estimates cited in this article were primarily drawn from this 1999 survey. RESULTS: Mixed practices were nearly evenly divided between large (area population, > or = 1 million) and small metropolitan areas (area population, from 50,000 to 1 million). We found that 63% of mixed practices were nonacademic private practices; 27% were academic. Approximately 50% contained 15 or more members. Mixed practices were predominantly owned by members of the practice and predominantly served both hospitals and nonhospital settings. At least 90% of mixed practices performed mammography, imaging-guided breast biopsy, sonography, and nuclear medicine.We found that compared with multiradiologist diagnostic radiology-only practices, mixed practices were larger and were more likely to be academic, to serve both hospital and nonhospital settings, and to perform interventional and nuclear medicine procedures. CONCLUSION: The characteristics of a mixed practice differ from those of a multiradiologist diagnostic radiology-only practice. 相似文献
88.
89.
Leighl NB Burkes RL Dancey JE Lopez PG Higgins BP David Walde PL Rudinskas LC Rahim YH Rodgers A Pond GR Shepherd FA 《Clinical lung cancer》2003,5(2):107-112
The purpose of this study was to determine the recommended phase II dose of liposomal doxorubicin (Caelyx ; Doxil in the United States) in combination with cyclophosphamide and vincristine for previously treated patients with good performance status with relapsed or refractory small-cell lung cancer. Twenty-one eligible patients were enrolled between November 1999 and September 2001 and received liposomal doxorubicin 25-40 mg/m2, cyclophosphamide 750-1000 mg/m2, and vincristine 1.2 mg/m2 intravenously (I.V.) every 21 days. At doses of liposomal doxorubicin 40 mg/m2, cyclophosphamide 750 mg/m2, and vincristine 1.2 mg/m2 I.V., 1 of 6 patients had dose-limiting neutropenia and fever in cycle 2 and 2 of 6 developed grade 3 hand-foot syndrome during cycle 3. Therefore, the recommended phase II doses are liposomal doxorubicin 35 mg/m2, cyclophosphamide 750 mg/m2, and vincristine 1.2 mg/m2 I.V. every 21 days. Antitumor activity was seen at all dose levels. This combination is well tolerated and has evidence of antitumor activity. A phase II evaluation is ongoing. 相似文献
90.
Determine HIV-1/2, Chembio HIV-1/2 STAT-PAK and PenTest are simple/rapid tests for the detection of antibodies to HIV-1 and HIV-2 in human whole blood, serum and plasma samples. The assay is one step and the result is read visually within 15 minutes. Using 92 known HIV-1 reactive sera and 108 known HIV-1 negative sera, the 3 HIV tests correctly identified all the known HIV-1 reactive and negative samples. The results indicated that Determine HIV-1/2, Chembio HIV-1/2 STAT-PAK and PenTest HIV are as sensitive and specific (100% concordance) as Microparticle Enzyme Immunoassay. The data indicated that these 3 HIV tests are effective testing systems for diagnosis of HIV infection in a situation when the conventional Enzyme Immunoassay is not suitable. 相似文献