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91.
OBJECTIVE: To critically examine the role of androgens as part of postmenopausal hormone replacement therapy. STUDY DESIGN: Examination of original reports and reviews obtained by electronic database searches and supplemented by manual search of bibliographies. RESULTS: As compared to estrogens alone, estrogen-androgen therapy may better protect against osteoporosis and increase libido, energy levels and general sense of well-being. However, estrogen-androgen replacement also reduces the beneficial increases in high-density lipoprotein induced by estrogens alone, although this effect may be offset at least partially by decreases in atherogenic triglycerides. The long-term net effect of estrogen-androgen replacement on cardiovascular disease remains unknown. CONCLUSION: Although the literature includes relatively few clinical trials or well-controlled studies and is further limited by the subjective nature of outcomes, such as sexual and psychological function, the available data suggest that for many postmenopausal women, estrogen-androgen replacement may provide benefits beyond those provided by estrogen-only replacement therapy. 相似文献
92.
JJ Milavetz TD Miller DO Hodge DR Holmes RJ Gibbons 《Canadian Metallurgical Quarterly》1998,82(7):857-861
Strategies to noninvasively evaluate patients after coronary stenting have not been evaluated. To determine the accuracy of single-photon emission computed tomography (SPECT) myocardial perfusion imaging in patients after coronary stenting, 209 patients who had undergone stenting followed by late stress SPECT myocardial perfusion imaging were evaluated. Quantitative coronary angiography was performed in 33 patients following SPECT imaging. SPECT restenosis was defined as a reversible or fixed defect within the stented vascular territory. Angiographic restenosis was examined using 2 definitions: total area narrowing > or =50% or > or =70% of the stent site or stented artery. The SPECT and angiographic findings were concordant in 22 of 33 stented vascular territories using the 50% definition of restenosis and in 29 of 33 stented territories using the 70% definition. Use of the 70% definition of restenosis resulted in improved accuracy of SPECT to detect a significant stenosis in the stented artery. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of SPECT were 95%, 73%, 88%, 89%, and 88% respectively. In patients with positive SPECT scans, the most significant stenosis in the stented artery was outside the stent site in 50% of cases. SPECT imaging appears to be accurate to predict significant stenosis in the stented artery, although the most severe stenosis is frequently distant from the stent site. 相似文献
93.
GS Stergiou AS Zourbaki II Skeva TD Mountokalakis 《Canadian Metallurgical Quarterly》1998,11(7):820-827
The objective of the study was to investigate whether home blood pressure (HBP) is a reliable alternative to ambulatory blood pressure (ABP) for the detection of the white coat effect (WCE). Hypertensive patients were randomized to measure HBP for 2 weeks or ABP for 24 h. The alternative measurement was then performed. Clinic blood pressure (CBP) was measured in the beginning and end of the study. Subjects with a difference of > or = 20 mm Hg systolic or > or = 10 mm Hg diastolic BP between CBP and awake ABP or CBP and HBP, were classified as clinic reactors. A total of 189 patients completed the study (79 on stable antihypertensive treatment). There was no difference in the magnitude of WCE assessed using the ABP or the HBP method (mean discrepancy, systolic BP: -1.5 +/- 11.7 mm Hg, 95% CI -3.2, 0.2; diastolic BP: 0.9 +/- 7.0, 95% CI -0.1, 1.9). A strong association existed between WCE calculated using the HBP or the ABP method (r = 0.64/0.59 systolic/diastolic, P < .001). The proportion of patients classified as clinic reactors was identical using the HBP or the ABP method (25.9%). Agreement between methods in the classification of clinic reactors was found in 147 patients (78%). The sensitivity and specificity of the HBP method to classify correctly clinic reactors (ABP method used as the standard) were 57% and 85%, respectively, whereas its positive and negative predictive value were 57% and 85%. These results indicate that HBP is not appropriate as an alternative to ABP diagnostic testing in the detection of WCE. Nevertheless, HBP appears useful as a screening test for the detection of this phenomenon. 相似文献
94.
A confusing number of measures are used to describe the effect sizes from clinical trials or systematic reviews. Absolute measures (absolute risk reduction, number needed to treat) and relative measures (relative risk reduction, relative risk or odds ratio) may give not just different numerical answers but convey different messages. This paper describes the role and meaning of the different measures, advises on their interpretation, and highlights the importance of taking into account the initial risk when assessing effect sizes from published studies. 相似文献
95.
TD Henry 《Canadian Metallurgical Quarterly》1998,351(9119):1826-1827
96.
PH Kilmarx K Limpakarnjanarat TD Mastro S Saisorn J Kaewkungwal S Korattana W Uthaivoravit NL Young BG Weniger ME St Louis 《Canadian Metallurgical Quarterly》1998,12(14):1889-1898
OBJECTIVES: To determine the incidence of HIV-1 infection, temporal trends in incidence, and risk factors for seroconversion in a cohort of female commercial sex workers (CSW) in upper northern Thailand, the region of Thailand with the highest rates of HIV-1 infection. METHODS: CSW were enrolled from 1991 through 1994 and evaluated prospectively with interviews, physical examination, testing for sexually transmitted diseases (STD), and serologic testing for HIV-1 infection. RESULTS: The incidence of HIV-1 seroconversion in the first year of follow-up was 20.3 per 100 person-years among 126 brothel-based CSW and 0.7 per 100 person-years among 159 other CSW who worked in other venues such as bars or massage parlors. Incidence remained elevated among brothel-based CSW who were enrolled later in the study compared with those who enrolled earlier. Through 1996, 30 women seroconverted. In a multivariable proportional hazards model, seroconversion was significantly associated (P < 0.05) with brothel-based sex work (adjusted risk ratio, 7.3) and Chlamydia trachomatis cervical infection (adjusted risk ratio, 3.3). CONCLUSION: Despite national HIV control efforts and declining rates of infection among young men in Thailand, brothel-based CSW may continue to be at high risk for HIV-1 infection. Additional efforts are needed to provide alternative economic choices for young women, to ensure universal condom use during commercial sex, and to develop new prevention technologies. 相似文献
97.
A growth curve is presented, that using the Tanner and Whitehouse's 50th centile, plots the height versus weight, both for males and females. The age is gives as parameter on the curves. In this way, weight, height and age are merged on a single chart for every sex. After exemplifying its advantages, the simpler relief of deviation from the values of the height-weight medians on the various ages, because the values of weight refer to the real height (and back), not to the age. With the same rule, curves relating to 10th and 90th centiles are processed by Tanner and Whitehouse's values. Collating between them, curves allow some morphological relief. Moreover, for both referred to the 50th centile of Tanner and Whitehouse curves (for the male sex and the female one), is presented a simple mathematical expression of interpolation, which shows and excellent representation of the measured dates. This expression is composed of a third-degree polynomial (cubic), which is fitted to the dates by the method of least square. The result of the correlation height-weight allows both to synthesize the dates in a sole expression and a simpler relief of discordance in the growth. 相似文献
98.
HR Costantino JD Andya PA Nguyen N Dasovich TD Sweeney SJ Shire CC Hsu YF Maa 《Canadian Metallurgical Quarterly》1998,87(11):1406-1411
We have examined the stability and aerosol performance of the pharmaceutical protein recombinant humanized anti-IgE monoclonal antibody (rhuMAbE25) spray dried with mannitol. The aerosol performance was measured by the fine particle fraction (FPF), and stability was assessed by the formation of soluble aggregates. When mannitol was added to the spray-dried rhuMAbE25 formulation, its ability to stabilize the protein leveled off above about 20% (w/w, dry basis). The FPF of the spray-dried formulations was stable during storage for rhuMAbE25 containing 10% and 20% mannitol, but the 30% formulation exhibited a dramatic decrease upon storage at both 5 degreesC and 30 degreesC, due to mannitol crystallization. We tested the addition of sodium phosphate to a 60:40 rhuMAbE25:mannitol (w:w) mixture, which otherwise crystallized upon spray drying and yielded a nonrespirable powder. The presence of sodium phosphate was successful in inhibiting mannitol crystallization upon spray drying and dramatically lowering the rate of solid-state aggregation. However, over long-term storage some crystallization was observed even for the phosphate-containing samples, concomitantly with increased particle size and decreased suitability for aerosol delivery. Therefore, the physical state of mannitol (i.e., amorphous or crystalline) plays a role both in maintaining protein stability and providing suitable aerosol performance when used as an excipient for spray-dried powders. Agents which retard mannitol crystallization, e.g., sodium phosphate, may be useful in extending the utility of mannitol as an excipient in spray-dried protein formulations. 相似文献
99.
100.
Three new dammarane-type triterpenoid saponins, bacopasaponins A, B and C, of biological interest have been isolated from the reputed Indian medicinal plant Bacopa monniera and identified as 3-O-alpha-L-arabinopyranosyl-20-O-alpha-L-arabinopyranosyl-+ ++jujubogenin, 3-O-[alpha-L-arabinofuranosyl (1--> 2)alpha-L-arabinopyranosyl]pseudojujubogenin and 3-O-[beta-D-glucopyranosyl (1 -->3)[alpha-L-arabinofuranosyl (1--> 2)]alpha-L-arabinopyranosyl]pseudojujubogenin by spectroscopic methods and some chemical transformations. The hitherto undetermined configurations at C-20 and C-22 of pseudojujubogenin were elucidated by phase-sensitive ROESY, and 1H and 13C signals of the saponins were assigned by DEPT, 1H-1H COSY, HSQC and HMBC techniques. 相似文献