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941.
942.
This study evaluates websites relevant to female hypoactive sexual desire disorder (HSDD). Its primary aim is to evaluate the quality of Internet HSDD information. One hundred and one websites, identified through simple Google searches, were scored using a tool incorporating expert consensus-derived quality criteria for HSDD. The tool included structural criteria such as currency, authorship, and disclosure of competing interests. It also included performance criteria, evaluating accuracy, and comprehensiveness, and was adapted from a published website evaluation tool for diabetes. For each website, a quality index score with a potential range from 1 to 5 (1 = poor, 5 = excellent) was calculated, and the websites were rank ordered using this score. Quality index scores ranged from 1.68 to 4.64, with 75% of websites scoring at or below 3.27. Test-retest reliability was moderate (n = 24, r = 0.6601, P = .0004). Rank ordering of the websites by quality index allowed identification of the top five highest quality websites. The majority of HSDD websites' quality scores fell in the score range from 1 to 3, indicating room for improvement in the quality of websites that address HSDD. Website evaluation tools utilizing both structural and performance quality criteria may help clinicians to assist their patients in assessing the quality of Internet health information. 相似文献
943.
Histomorphometric assessment of the long-term effects of alendronate on bone quality and remodeling in patients with osteoporosis. 总被引:14,自引:2,他引:14
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P M Chavassieux M E Arlot C Reda L Wei A J Yates P J Meunier 《The Journal of clinical investigation》1997,100(6):1475-1480
Treatment effects on bone quality and remodeling was assessed in postmenopausal women with osteoporosis treated with oral alendronate. One transiliac bone biopsy was obtained from 231 women at either 24 mo (n = 11) or 36 mo (n = 120) from the start of treatment with alendronate at doses of between 5 and 20 mg/d, or placebo. 64 biopsies at 24 mo (31 from the placebo group and 33 alendronate-treated patients) and 95 biopsies at 36 mo (40 from the placebo group and 55 alendronate-treated patients) provided adequate cancellous tissue, and were analyzed by histomorphometry. Mineral apposition rate was unaffected by treatment. At 24 and 36 mo, osteoid thickness, volume, and surface significantly decreased. At each of the doses studied, mineralizing surface and activation frequency significantly decreased at each time point (e.g., -92% and -87%, respectively, for the 10 mg daily dose after 2 yr). These diminutions were of the same magnitude for each dose at 24 mo, and for the two highest doses at 36 mo. A significant increase in wall thickness accompanied by a reduction in erosion depth was detected in biopsies obtained at 24 mo. These findings confirm that mineralization is normal, and trabecular bone turnover markedly decreased in patients receiving long-term dosing with alendronate. The findings also suggest that the observed increases in bone mineral density could result both from a reduction in the remodeling space due to a decreased activation frequency and a possible trend to a positive bone balance. In addition, further studies focused on a possible increase in the degree of mineralization of bone are required. 相似文献
944.
Effects of Acetazolamide on the Unrinary Excretion of Cyclic AMP and on the Activity of Renal Adenyl Cyclase
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Hector J. Rodriguez John Walls Jesse Yates Saulo Klahr 《The Journal of clinical investigation》1974,53(1):122-130
Acetazolamide, an inhibitor of the enzyme carbonic anhydrase, increased the urinary excretion of cyclic AMP in normal and parathyroidectomized rats. The increase was greater in rats with intact parathyroid glands than in parathyroidectomized rats. This rise in the urinary excretion of cyclic AMP was not due to an increase in urine flow or a change in urine pH. Furosemide caused an increase in urine flow, but did not affect the excretion of cyclic AMP or phosphate. Alkalinization of the urine with bicarbonate did not increase the urinary excretion of phosphate or cyclic AMP. Acetazolamide increased the productionof cyclic AMP by rat renal cortical slices in vitro. This effect was dose-dependent. Acetazolamide also stimulated the activity of renal cortical adenyl cyclase in a dose-dependent manner but had no effect on the activity of cyclic nucleotide phosphodiesterase. The pattern of urinary excretion of cyclic AMP and phosphate after administration of acetazolamide was similar to that observed in rats given parathyroid hormone. It is suggested that acetazolamide stimulates the renal production of cyclic AMP by activating adenyl cyclase and that this may be the mechanism by which this inhibitor of carbonic anhydrase produces phosphaturia. 相似文献
945.
High frequency transfer and horizontal spread of apramycin resistance in calf faecal Escherichia coli 总被引:1,自引:0,他引:1
Yates CM Pearce MC Woolhouse ME Amyes SG 《The Journal of antimicrobial chemotherapy》2004,54(2):534-537
OBJECTIVES: The aminoglycoside apramycin has been used extensively in animal husbandry in the UK since 1978. This study aimed to determine both whether calves that had never been treated with aminoglycoside antibiotics harboured apramycin-resistant (apr(R)) commensal Escherichia coli, and the mode of spread of the resistance gene. METHODS: Apr(R) E. coli from weekly calf faecal samples were typed by pulsed-field gel electrophoresis, antibiotic resistance phenotype, plasmid restriction profiles and plasmid transfer frequencies. RESULTS: During 4 months of weekly sampling, six of 11 calves were found to harbour apr(R) E. coli. All apr(R) E. coli (45) were cross-resistant to gentamicin and tobramycin, which are both used in human medicine. Resistance was conferred by the aac(3)IV gene, present on three different conjugative plasmids. Two of these plasmids also mediated tetracycline and streptomycin resistance. One plasmid demonstrated very high transfer frequencies and was found in three different genotypes. CONCLUSIONS: We report the presence of apr(R) commensal E. coli in cattle that have never been treated with aminoglycosides. The presence of one conjugative plasmid in three different genotypes is evidence of horizontal spread of this plasmid. This is the first report of a very high transfer frequency of apr(R) plasmid, demonstrating horizontal spread in the commensal flora of food animals. 相似文献
946.
Hongyuan Jiang Christopher J. Yates Alexandra Gorelik Ashwini Kale Qichun Song John D. Wark 《Journal of clinical densitometry》2018,21(1):140-147
Dual-energy X-ray absorptiometry (DXA) as currently used has limitations in identifying patients with osteoporosis and predicting occurrence of fracture. We aimed to express peripheral quantitative computed tomography (pQCT) variables of patients with low-trauma fracture as T-scores by using T-score scales obtained from healthy young women, and to evaluate the potential clinical utility of pQCT for the assessment of bone fragility. Fracture patients were recruited from a fracture liaison service at the Royal Melbourne Hospital. Reference pQCT data were obtained from studies on women's health conducted by our group. A study visit was arranged with fracture patients, during which DXA and pQCT were applied to measure their bone strength. A total of 59 fracture patients were recruited, and reference data were obtained from 78 healthy young females. All DXA variables and most pQCT variables were significantly different between healthy young females and fracture patients (p?<?0.05), except polar stress-strain index (p?=?0.34) and cortical bone density (p?=?0.19). Fracture patients were divided into osteoporosis and non-osteoporosis groups according to their DXA T-scores. Significant differences were observed in most pQCT variables (p?<?0.05), except trabecular area and cortical density (p?>?0.9 and p?=?0.5, respectively). By applying pQCT T-scores, 11 (27%) of patients who were classified as having low or medium risk of osteoporosis on DXA T-scores alone were reclassified as high risk. Results of logistic regression suggested trabecular bone density as an independent predictor of osteoporosis status. More patients can be identified with osteoporosis by applying pQCT T-score variables in older people with low-trauma fracture. Peripheral QCT T-scores contribute to the understanding of bone fragility in this population. 相似文献
947.
Tolerability of once-weekly alendronate in patients with osteoporosis: a randomized,double-blind,placebo-controlled study 总被引:5,自引:0,他引:5
Greenspan S Field-Munves E Tonino R Smith M Petruschke R Wang L Yates J de Papp AE Palmisano J 《Mayo Clinic proceedings. Mayo Clinic》2002,77(10):1044-1052
OBJECTIVE: To compare the upper gastrointestinal (GI) tract tolerability of once-weekly oral alendronate, 70 mg, and placebo. PATIENTS AND METHODS: This was a 12-week multicenter, randomized, double-blind, placebo-controlled study. The first patient initiated treatment on June 5, 2000, and the last patient completed treatment on March 1, 2001. The study enrolled 450 postmenopausal women and men with osteoporosis (224 took alendronate, 226 took placebo) who were ambulatory and community dwelling at 48 outpatient study centers in the United States. By design, approximately half of the patients were naive to bisphosphonates. The primary end point was upper GI tract tolerability based on the incidence of any upper GI tract adverse events. Secondary end points included the number of discontinuations due to drug-related upper GI tract adverse events and the change from baseline in bone resorption, assessed by the urinary N-telopeptide-creatinine ratio at 12 weeks. A subgroup analysis of the primary and secondary end points was performed on the patients stratified by prior bisphosphonate use. The safety and tolerability of the weekly alendronate and placebo regimens were captured as clinical and laboratory adverse events. RESULTS: A total of 11% of the alendronate patients and 13% of the placebo patients reported an upper GI tract adverse event. Discontinuations due to drug-related upper GI tract adverse events occurred in 3% of alendronate patients and 1% of placebo patients. The differences between the treatment groups for the primary and secondary end points were not significant. For the primary end point, the upper limit of the 95% confidence interval of the difference was well within the prespecified 14% comparability bound (-2.2%; 95% confidence interval, -8.3% to 3.9%). The overall incidence of upper GI tract adverse events was lower in the subgroup of patients with prior bisphosphonate exposure (8%) than in those who were bisphosphonate naive (16%). However, regardless of prior bisphosphonate exposure, the incidence of upper GI tract adverse events was similar between the alendronate and placebo patients. The urinary N-telopeptide-creatinine ratio showed a significant decrease in the alendronate patients (72% of baseline, P<.001) compared with a slight increase in the placebo patients (106% of baseline) at week 12. CONCLUSION: In this 3-month study, the incidence of upper GI tract adverse events in patients treated with once-weekly alendronate, 70 mg, was comparable to that with placebo. 相似文献
948.
Michele C. Hlavsa Bryanna L. Cikesh Virginia A. Roberts Amy M. Kahler Marissa Vigar Elizabeth D. Hilborn Timothy J. Wade Dawn M. Roellig Jennifer L. Murphy Lihua Xiao Kirsten M. Yates Jasen M. Kunz Matthew J. Arduino Sujan C. Reddy Kathleen E. Fullerton Laura A. Cooley Michael J. Beach Vincent R. Hill Jonathan S. Yoder 《American journal of transplantation》2018,18(7):1815-1819
949.
Human DNA replication initiation factors, ORC and MCM, associate with oriP of Epstein-Barr virus
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Chaudhuri B Xu H Todorov I Dutta A Yates JL 《Proceedings of the National Academy of Sciences of the United States of America》2001,98(18):10085-10089
The 165-kb chromosome of Epstein-Barr virus (EBV) is replicated by cellular enzymes only once per cell cycle in human cells that are latently infected. Here, we report that the human origin recognition complex, ORC, can be detected in association with an EBV replication origin, oriP, in cells by using antibodies against three different subunits of human ORC to precipitate crosslinked chromatin. Mcm2, a subunit of the MCM replication licensing complex, was found to associate with oriP during G(1) and to dissociate from it during S phase. The detection of ORC and Mcm2 at oriP was shown to require the presence of the 120-bp replicator of oriP. Licensing and initiation of replication at oriP of EBV thus seem to be mediated by ORC. This is an example of a virus apparently using ORC and associated factors for the propagation of its genome. 相似文献
950.
From 1980 through 1994, we identified 47 adult patients with acquired pure red cell aplasia (median age, 64 years; range, 22 to 84 years). Associated clinical disorders included T-cell large granular lymphocytic (LGL) leukemia, thymoma, chronic lymphocytic leukemia, and non-Hodgkin's lymphoma. Review of bone marrow findings in 40 patients showed absence of erythroid precursors in 14 patients and rare pronormoblasts in 26. None had morphologic evidence of myelodysplasia. T-cell receptor gene rearrangement studies with Southern blot technique in 14 patients showed clonal rearrangements in nine. Karyotypic analyses performed in 28 patients showed clonal abnormalities in four. Overall, 28 of 47 patients (60%) responded to immunosuppressive therapy, but none were the patients with cytogenetic abnormalities. There was a trend toward superior response to immunosuppressive agents in the patients with T-cell LGL leukemia. Cyclophosphamide, with or without corticosteroids, was the most useful treatment agent. Cyclosporine A was effective for refractory disease. Neither the presence of an associated clinical disorder nor the existence of detectable erythroid precursors affected overall survival. We conclude that (1) T-cell LGL leukemia is the disorder most commonly associated with pure red cell aplasia, (2) the presence of clonal cytogenetic abnormality predicts poor response to immunosuppressive therapy, and (3) oral cyclophosphamide and cyclosporine A are effective treatment regimens. 相似文献