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Suma Prakash Rick Coffin Jesse Schold Steven A. Lewis Douglas Gunzler Susan Stark Matthew Howard Darlene Rodgers Douglas Einstadter Ashwini R. Sehgal 《Peritoneal dialysis international》2014,34(1):24-32
♦ Introduction: Rural residence is associated with increased peritoneal dialysis (PD) utilization. The influence of travel distance on rates of home dialysis utilization has not been examined in the United States. The purpose of this study was to determine whether travel distances to the closest home and in-center hemodialysis (IHD) facilities are a barrier to home dialysis.♦ Methods: This was a retrospective cohort study of patients aged ≥ 18 years initiating dialysis between 2005 and 2011. Unadjusted PD and home hemodialysis (HHD) rates were compared by travel distances to both the closest home dialysis and closest IHD facilities. Adjusted PD and HHD utilization rates were examined using multivariable logistic regression models.♦ Results: There were 98,608 patients in the adjusted analyses. 55.5% of the dialysis facilities offered home dialysis. IHD, PD and HHD patients traveled median distances of 5.4, 3.5 and 6.6 miles respectively to their initial dialysis facilities. Unadjusted analyses showed an increase in PD rates and decrease in HHD rates with increased travel distances. Adjusted odds of PD and HHD were 1.6 and 1.2 respectively for a ten mile increase in distance to the closest home dialysis facility, while for distances to the closest IHD facility the odds ratios for both PD and HHD were 0.7 (all p < 0.01).♦ Conclusions: In metropolitan areas, PD and HHD generally increased with increased travel distance to the closest home dialysis facility and decreased with greater distance to an IHD facility. Examination of travel distances to PD and HHD facilities separately may provide further insight on specific barriers to these modalities which can serve as targets for future studies examining expansion of home dialysis utilization. 相似文献
124.
Rohit Singh Produl Hazarika Dipak Ranjan Nayak R. Balakrishnan Navneeta Gangwar Manali Hazarika 《Indian journal of otolaryngology and head and neck surgery》2013,65(3):193-196
Nasal polyposis is often encountered in rhinology practice. Those who fail conservative management, a definitive surgery is essential to achieve sufficient ventilation and drainage of the affected sinuses by using either microdebrider or conventional instruments for functional endoscopic sinus surgery (FESS). A prospective study was conducted on 40 cases of nasal polypi in a tertiary care hospital. 20 cases were operated by conventional endoscopic instruments and 20 using the microdebrider. The study aimed at comparing the intra operative (blood loss, duration of surgery) and post operative results (crusting, scarring, discharge, symptoms, recurrence) between the two groups using Lund–Mackay scoring system and the data was statistically analysed. There was no statistically significant difference in surgical outcome for patients when either conventional endoscopic instruments or microdebrider was used. However, there was a significant symptomatic improvement in cases undergoing microdebrider FESS. Microdebrider assisted polypectomy is precise, relatively bloodless surgery though the precision depends on the surgeon’s anatomical knowledge and operative skills. Study substantiates that these instruments are helpful but not a prerequisite for successful outcomes in FESS. The study re-emphasises the utility of the microdebrider to young learning FESS surgeons. 相似文献
125.
The role of urinary pH in o‐phenylphenol‐induced cytotoxicity and chromosomal damage in the bladders of F344 rats
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S. Balakrishnan L. Hasegawa D.A. Eastmond 《Environmental and molecular mutagenesis》2016,57(3):210-219
o‐Phenylphenol (OPP) is a widely used fungicide and antibacterial agent that at high doses has been shown to cause bladder cancer in male F344 rats. The mechanisms underlying OPP‐induced bladder carcinogenicity remain unclear but it has been proposed that a non‐enzymatic pH‐dependent autoxidation of phenylhydroquinone (PHQ), a primary metabolite of OPP, may be a key step in OPP‐induced rat bladder carcinogenesis. To investigate this mechanism and to provide insights into the potential human health relevance of OPP‐induced cancer, a series of in vitro and in vivo experiments were conducted. In human lymphoblastoid TK‐6 cells and rat bladder epithelial NBT‐II cells, strong increases in cytotoxicity were seen at a constant concentration of PHQ by increasing the buffer pH as well as by increasing concentrations of PHQ at a constant pH. In in vivo studies, male rats were administered OPP (4,000 and 8,000 ppm) in a diet supplemented with either 1% ammonium chloride or 3% sodium bicarbonate to produce acidic and alkaline urinary pH, respectively. Significant increases in cell proliferation as detected by 5‐bromo‐2′‐deoxyuridine incorporation and micronucleus formation were seen in the bladder cells of OPP‐treated rats with neutral or alkaline urinary pH but not in animals with the acidified urine. The results from these in vitro and in vivo studies provide support for the autoxidation hypothesis of bioactivation, and provide additional evidence that urinary pH can significantly influence the genotoxicity and carcinogenicity of this important agent. Environ. Mol. Mutagen. 57:210–219, 2016. © 2016 Wiley Periodicals, Inc. 相似文献
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127.
Caroline F. Bull Graham Mayrhofer Dimphy Zeegers Grace Low Kah Mun M. Prakash Hande Michael F. Fenech 《Environmental and molecular mutagenesis》2012,53(4):311-323
Chromosomal instability (CIN) is an important hallmark to oncogenesis and can be diagnosed morphologically by the presence of nuclear anomalies such as micronuclei (MN), nucleoplasmic bridges (NPBs), and nuclear buds (NBuds). We have identified additional nuclear anomalies formed under folate‐deficient conditions, defined as “fused” nuclei (FUS), “circular” nuclei (CIR), and “horse‐shoe” nuclei (HS) and investigated their suitability for inclusion as additional CIN biomarkers in the lymphocyte cytokinesis‐block micronucleus cytome (CBMN‐Cyt) assay. Although the morphological appearance of FUS, CIR, and HS suggested an origin from multiple NPB in the fusion region between the two nuclei, the very low frequency of dicentric chromosomes in metaphase spreads from these cultures did not support this model. Fluorescence in situ hybridization (FISH) analysis of cytokinesis‐blocked binucleated (BN) cells with peptide nucleic acid probes for telomeres and centromeres (PNA–FISH) revealed a high proportion of fusion regions contained both centromeric and telomeric DNA. This suggests that folate deficiency may disrupt the process of sister chromatid separation and chromosome segregation during mitosis. It was concluded that the FUS, CIR, and HS morphologies represent promising biomarkers of CIN that are sensitive to folate deficiency, and further validation and investigation of the mechanisms responsible for their formation is warranted. Mol. Mutagen. 2012. © 2012 Wiley Periodicals, Inc. 相似文献
128.
J. Ravindran C. Cavill C. Balakrishnan S. M. Jones E. Korendowych N. J. McHugh 《Arthritis care & research》2010,62(1):86-91
Objective
To use a modified Sharp score (MSS) to measure radiologic progression and to assess its relationship to other radiologic features, peripheral joint disease, and physical function in psoriatic arthritis (PsA).Methods
Two sets of hand radiographs (median interval 5.75 years) in 139 patients with established PsA were scored using an MSS. Seventy‐four patients had standardized clinical joint and Health Assessment Questionnaire (HAQ) scores and other radiologic features of PsA documented at baseline and followup (median interval 5 years).Results
Radiologic damage was present in 58% of patients at baseline and 74% at followup. The median MSS and its components, erosion score and joint space abnormality score, were significantly greater at followup (P < 0.001). The median MSS progression was +1.08 units/year. There was strong correlation between MSS and clinical joint scores at baseline and followup (r = 0.72 and r = 0.81, respectively). There was weak correlation between MSS and HAQ at baseline (r = 0.29), but stronger correlation at followup (r = 0.48). There was a strong association between MSS and other characteristic radiologic features of PsA (bony proliferation, periostitis, bony ankylosis) at baseline and followup (P < 0.001). However, the presence of soft‐tissue swelling on radiographs at baseline was the only radiologic parameter associated with an increased rate of change of MSS (corrected P < 0.006).Conclusion
The MSS shows good construct validity with measures of peripheral joint involvement such as clinical joint scores and other radiologic features of PsA, and is able to demonstrate that radiologic damage is progressive beyond early disease. 相似文献129.
Sangeetha Jayaraman Somesh Balakrishnan Devaji Rao 《The Indian journal of surgery》2011,73(5):377-379
Development of a primary cancer after treatment of the first with radiotherapy or chemotherapy is well documented, but it
is common with hematological malignancies. Variety of reasons are suggested by various researchers, but a conclusive evidence
is not yet available. Excepting a few correlations like the tamoxifen therapy and endometrial cancer, angiosarcoma of the
breast following radiotherapy, occurrence of other metachronous malignancies seem to be dependent on genetic and environmental
factors. A patient with three primary malignancies is presented here. 相似文献
130.
Bikash Medhi Ajay Prakash Sujata Upadhyay Deonis Xess T. D. Yadav L. Kaman 《The Indian journal of surgery》2011,73(6):427-431
Diltiazem has been extensively studied in the treatment of chronic anal fissures, but efficacy in clinical practice is not
fully established. The aim of the present study was to evaluate the safety and efficacy of topical application diltiazem in
observational studies as well as in controlled clinical trials in the treatment of chronic anal fissures. A systematic literature
search was carried out from 1966 to 31 December, 2007 on PubMed, Medline, Embase and Cochrane database, using the appropriate
search words. We found six observational studies with 392 patients and five controlled clinical trials with 289 patients in
which topical diltiazem treatment was given. Efficacy was found to be very high in observational studies (56.88%), whereas
it was found to be modest in controlled clinical trials (29.41%). In observational studies, most of the patients reported
complete healing of fissures within 6–12 weeks, whereas in controlled trials healing was reported within 8 weeks, with tolerable
adverse effects of diltiazem. On the basis of the above studies, it can be concluded that topical application of diltiazem
is useful in the treatment of chronic anal fissure, but to fully establish its efficacy, larger prospective double-blind study
is required in the near future. 相似文献