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151.
Effects of conjugated equine estrogen in postmenopausal women with hysterectomy: the Women's Health Initiative randomized controlled trial 总被引:55,自引:12,他引:43
Anderson GL Limacher M Assaf AR Bassford T Beresford SA Black H Bonds D Brunner R Brzyski R Caan B Chlebowski R Curb D Gass M Hays J Heiss G Hendrix S Howard BV Hsia J Hubbell A Jackson R Johnson KC Judd H Kotchen JM Kuller L LaCroix AZ Lane D Langer RD Lasser N Lewis CE Manson J Margolis K Ockene J O'Sullivan MJ Phillips L Prentice RL Ritenbaugh C Robbins J Rossouw JE Sarto G Stefanick ML Van Horn L Wactawski-Wende J Wallace R Wassertheil-Smoller S;Women's Health Initiative Steering Committee 《JAMA》2004,291(14):1701-1712
Context Despite decades of use and considerable research, the role of estrogen alone in preventing chronic diseases in postmenopausal women remains uncertain. Objective To assess the effects on major disease incidence rates of the most commonly used postmenopausal hormone therapy in the United States. Design, Setting, and Participants A randomized, double-blind, placebo-controlled disease prevention trial (the estrogen-alone component of the Women's Health Initiative [WHI]) conducted in 40 US clinical centers beginning in 1993. Enrolled were 10 739 postmenopausal women, aged 50-79 years, with prior hysterectomy, including 23% of minority race/ethnicity. Intervention Women were randomly assigned to receive either 0.625 mg/d of conjugated equine estrogen (CEE) or placebo. Main Outcome Measures The primary outcome was coronary heart disease (CHD) incidence (nonfatal myocardial infarction or CHD death). Invasive breast cancer incidence was the primary safety outcome. A global index of risks and benefits, including these primary outcomes plus stroke, pulmonary embolism (PE), colorectal cancer, hip fracture, and deaths from other causes, was used for summarizing overall effects. Results In February 2004, after reviewing data through November 30, 2003, the National Institutes of Health (NIH) decided to end the intervention phase of the trial early. Estimated hazard ratios (HRs) (95% confidence intervals [CIs]) for CEE vs placebo for the major clinical outcomes available through February 29, 2004 (average follow-up 6.8 years), were: CHD, 0.91 (0.75-1.12) with 376 cases; breast cancer, 0.77 (0.59-1.01) with 218 cases; stroke, 1.39 (1.10-1.77) with 276 cases; PE, 1.34 (0.87-2.06) with 85 cases; colorectal cancer, 1.08 (0.75-1.55) with 119 cases; and hip fracture, 0.61 (0.41-0.91) with 102 cases. Corresponding results for composite outcomes were: total cardiovascular disease, 1.12 (1.01-1.24); total cancer, 0.93 (0.81-1.07); total fractures, 0.70 (0.63-0.79); total mortality, 1.04 (0.88-1.22), and the global index, 1.01 (0.91-1.12). For the outcomes significantly affected by CEE, there was an absolute excess risk of 12 additional strokes per 10 000 person-years and an absolute risk reduction of 6 fewer hip fractures per 10 000 person-years. The estimated excess risk for all monitored events in the global index was a nonsignificant 2 events per 10 000 person-years. Conclusions The use of CEE increases the risk of stroke, decreases the risk of hip fracture, and does not affect CHD incidence in postmenopausal women with prior hysterectomy over an average of 6.8 years. A possible reduction in breast cancer risk requires further investigation. The burden of incident disease events was equivalent in the CEE and placebo groups, indicating no overall benefit. Thus, CEE should not be recommended for chronic disease prevention in postmenopausal women. 相似文献
152.
Margolis RL Holmes SE Rosenblatt A Gourley L O'Hearn E Ross CA Seltzer WK Walker RH Ashizawa T Rasmussen A Hayden M Almqvist EW Harris J Fahn S MacDonald ME Mysore J Shimohata T Tsuji S Potter N Nakaso K Adachi Y Nakashima K Bird T Krause A Greenstein P 《Annals of neurology》2004,56(5):670-674
Huntington's Disease-like 2 (HDL2) is a progressive, autosomal dominant, neurodegenerative disorder with marked clinical and pathological similarities to Huntington's disease (HD). The causal mutation is a CTG/CAG expansion mutation on chromosome 16q24.3, in a variably spliced exon of junctophilin-3. The frequency of HDL2 was determined in nine independent series of patients referred for HD testing or selected for the presence of an HD-like phenotype in North America or Japan. The repeat length, ancestry, and age of onset of all North American HDL2 cases were determined. The results show that HDL2 is very rare, with a frequency of 0 to 15% among patients in the nine case series with an HD-like presentation who do not have the HD mutation. HDL2 is predominantly, and perhaps exclusively, found in individuals of African ancestry. Repeat expansions ranged from 44 to 57 triplets, with length instability in maternal transmission detected in a repeat of r2=0.29, p=0.0098). The results further support the evidence that the repeat expansion at the chromosome 16q24.3 locus is the direct cause of HDL2 and provide preliminary guidelines for the genetic testing of patients with an HD-like phenotype. 相似文献
153.
Brandt J Leroi I O'Hearn E Rosenblatt A Margolis RL 《The Journal of neuropsychiatry and clinical neurosciences》2004,16(2):176-184
To determine the specificity of cognitive impairments in patients with cerebellar degeneration (CD), the neuropsychological test performance of 31 CD patients was compared to that of 21 patients with Huntington's disease (HD) and 29 normal adults. The CD and HD groups did not differ in age, education, or duration of illness, and their overall severity on a quantified neurological examination was similar. Fifteen neuropsychological test variables were reduced to five underlying domains: motor, verbal, spatial, memory, and executive functioning. The CD patients had their greatest impairment in the executive domain and their least in the memory domain. In contrast, the HD patients had very substantial spatial deficits and significant memory impairment, in addition to executive dysfunction. The findings indicate that 1) the cognitive impairment in CD is not as severe as in HD, and 2) the pattern of deficits in CD, while consistent with a subcortical dementia, differs in important ways from that in HD. These differences may reflect the involvement of the cerebellar dentate nucleus and the striatal nuclei in separate "loops" or closed circuits, linking them with specific areas of cerebral neocortex. 相似文献
154.
Liszewski CM O'Hearn E Leroi I Gourley L Ross CA Margolis RL 《The Journal of neuropsychiatry and clinical neurosciences》2004,16(1):109-112
The authors performed a chart review to determine the frequency with which neurologists detect cognitive and psychiatric symptoms in patients with cerebellar degeneration. Psychopathology, including depression, personality change, cognitive impairment, anxiety, and psychosis was noted in 51% of 133 patients. 相似文献
155.
156.
Varaprasathan G Miller K Lietman T Whitcher JP Cevallos V Okumoto M Margolis TP Yinghui M Cunningham ET 《Cornea》2004,23(4):360-364
OBJECTIVE: We analyzed laboratory results from corneal ulcers seen from 1976 to 1999 at the Francis I. Proctor Foundation, a referral center in San Francisco, to determine the relative frequencies of pathogens and to analyze for trends in frequencies of the most common pathogens. The results were compared with a previous study of corneal ulcers seen from 1948 to 1976 at the same institution. METHODS: Ulcers presenting to the Proctor Foundation were Gram stained and cultured using standard techniques. Herpetic corneal ulcers were excluded from the study. RESULTS: Organisms were isolated from 427 ulcers, 38% of all cases. Two hundred seventy-eight (59%) isolates were gram-positive bacteria, 145 (31%) gram-negative bacteria, 16 (3%) Acanthamoeba spp., and 36 (8%) fungi. Staphylococcus aureus was the most common organism, composing 20% of all isolates, followed by viridans group streptococci (12%), Streptococcus pneumoniae (11%), Pseudomonas aeruginosa (6%), Moraxella spp. (5%), and Serratia marcescens (4%). Over the 24-year study period the proportion of positive cultures decreased and the incidence of S. marcescens increased significantly. Comparing the period of 1948-1976 to 1976-1999, the frequency of S. pneumoniae and P. aeruginosa decreased, and that of S. marcescens increased significantly. CONCLUSION: The common pathogens associated with corneal ulcers have changed over the past 50 years in Northern California, with S. pneumoniae and P. aeruginosa being isolated relatively less often and S. marcescens being isolated with increasing frequency. The decrease in isolation of organisms over the 1976-1999 period may have resulted from increasing empiric antibiotic treatment by referring ophthalmologists. 相似文献
157.
Recent work suggests that herpes simplex virus (HSV) stromal keratitis in the mouse is caused by autoreactive T lymphocytes triggered by a 16 amino acid region of the HSV UL6 protein (aa299-314), Science 279, 1344-1347). In the present study we sought to determine whether genetic variation of this presumed autoreactive UL6 epitope is responsible for different pathogenic patterns of human HSV keratitis. To accomplish this, we sequenced the HSV UL6 gene from ocular isolates of 10 patients with necrotizing stromal keratitis, 7 patients with recurrent epithelial keratitis, and 8 patients with other forms of HSV keratitis. The sequences obtained predicted identical UL6(299-314) epitopes for all 25 viral isolates. Furthermore, the upstream sequence of all isolates was free of insertions, deletions, and stop codons. We conclude that different pathogenic patterns of human HSV keratitis occur independent of genetic variation of the HSV UL6 (299-314) epitope. 相似文献
158.
OBJECTIVE: The goal of this study was to evaluate whether simple risk factors can be identified that successfully characterize who will heal and who will not heal among patients who have received standard therapy for diabetic neuropathic foot ulcers. RESEARCH DESIGN AND METHODS: For this cohort study, we evaluated >31,000 individuals with a diabetic neuropathic foot ulcer seen in the Curative Health Services System. Using multivariate logistic regression, we evaluated the association between wound size, wound duration, wound grade, and other variables and their effect on whether a patient would heal by the 20th week of care. RESULTS: We demonstrated that wound size, wound duration, and wound grade are all significantly associated with the likelihood of a wound healing by the 20th week of care. In addition, we noted that these associations were not significantly affected by the treating wound care center, whether the unit of analysis was one wound on a patient or all of their wounds, or current adjuvant therapies. CONCLUSIONS: We have shown that three easy-to-measure risk factors are associated with a wound healing. These results should help clinicians understand the likelihood that a wound will heal and help those conducting clinical investigations to design better trials. 相似文献
159.
BACKGROUND: The accurate and reproducible measurement of ascorbic acid is essential in delineating the role of ascorbic acid as a diagnostic tool for human disease and for the comparison of data acquired by different laboratories. A stabilized pair of standards of ascorbic acid in human serum, which is compatible with most analytical methods, have been prepared. METHODS: The certification was based on the gravimetric addition of ascorbic acid to metaphosphoric acid-stabilized, ascorbic acid-depleted serum and NIST liquid chromatography-electrochemical measurements. The NIST results were analyzed statistically for homogeneity, and the expanded uncertainty of each SRM was calculated using all of the NIST data. An interlaboratory comparison exercise was also performed. RESULTS: These materials, Standard Reference Material (SRM) 970 Ascorbic Acid in Serum, Level I and Level II, are homogeneous and are certified to contain (10.07 +/- 0.21) and (30.57 +/- 0.28) mmol ascorbic acid/L of solution (expanded uncertainty), respectively. In the interlaboratory comparison (n = 17), the relative SDs for the two materials were 22% and 19%. CONCLUSIONS: Two lots of serum, each containing different amounts of ascorbic acid stabilized in metaphosphoric acid, have been prepared and characterized. Many laboratories provide inaccurate results. 相似文献
160.
Genetic variation of hepatitis B surface antigen coding region among infants with chronic hepatitis B virus infection 总被引:8,自引:0,他引:8
Nainan OV Khristova ML Byun K Xia G Taylor PE Stevens CE Margolis HS 《Journal of medical virology》2002,68(3):319-327
Variants in the amino acid composition of the primary antibody-binding site of hepatitis B surface antigen (HBsAg) have been identified in a number of populations with chronic hepatitis B virus (HBV) infection. Direct sequencing of amplified or cloned PCR products, solid phase detection of sequence-specific PCR products (SP-PCR), and limiting dilution cloning PCR (LDC-PCR) were compared to determine their sensitivity in detecting differing concentrations of HBsAg variants. LDC-PCR had the greatest sensitivity and could detect HBsAg variants at a concentration of 0.1% of the total viral population. HBsAg variants were detected in 51% of infants with chronic HBV infection acquired after postexposure prophylaxis, and more than half of the variants were detected only by the most sensitive methods. 相似文献