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991.
992.
An extract of the roots of Angelica dahurica BENTH. et HOOK. (Umbelliferae) showed potential tyrosinase inhibition against mushroom tyrosinase. Employing a bioassay-linked HPLC method, followed by semipreparative HPLC, the active principle was isolated and characterized as 9-hydroxy-4-methoxypsoralen. 相似文献
993.
994.
Partnering with a reference lab can actually help grow a referring lab's own business. The reference lab provides a hospital's physicians with access to unique tests and clinical information and broadens the scope and depth of the referring lab's menu. As medicine moves toward prescribed treatments based on a patient's individual genotype or phenotype, the reference lab will play an even bigger role in helping the hospital to educate physicians and their patients to the most efficient testing strategies consistent with good patient management. 相似文献
995.
996.
There are many arguments to support the hypothesis that there is a causal relationship between the presence of endometriosis and subfertility. These arguments are reviewed in this article and include: (1) an increased prevalence of endometriosis in subfertile women compared with women of proven fertility; (2) a reduced monthly fecundity rate (MFR) in baboons with mild to severe (spontaneous or induced) endometriosis compared with those with minimal endometriosis or a normal pelvis; (3) a trend toward a reduced MFR in infertile women with minimal to mild endometriosis compared with women with unexplained infertility; (4) a dose-effect relationship: a negative correlation between the r-AFS stage of endometriosis and the monthly fecundity rate and crude pregnancy rate; (5) a reduced monthly fecundity rate and cumulative pregnancy rate after donor sperm insemination in women with minimal-mild endometriosis compared with those with a normal pelvis; (6) a reduced MFR after husband sperm insemination in women with minimal to mild endometriosis compared with those with a normal pelvis; (7) a reduced implantation rate per embryo after IVF in women with moderate to severe endometriosis compared with women with a normal pelvis; and (8) an increased monthly fecundity rate and cumulative pregnancy rate after surgical removal of minimal to mild endometriosis. 相似文献
997.
998.
This paper focuses on patterns in the care of children and dependent elders, providing a new perspective to understand impairment in family caregiving. One concept from evolutionary theory, kin selection, has promise for providing a broad framework for understanding patterns of family caregiving. We present an application of the evolutionary model to the issue of family care decisions in the face of potential conflicts of interest. Specifically, a mathematical biological model, which was developed to understand self-preservation motivation, is applied to the kin investment decision. Using the evolutionary model, the main predictors of investment would be relatedness, reproductive value, and expected benefit from the care invested. The biological model accounts very simply for decisions between caring for an elder parent or caring for your own child, and for decisions by two daughters (one with a child, one childless) to care for an elder parent. The factors that form the basis of an evolutionary model (relatedness, reproductive value, and benefit from care) have not been widely investigated in family care studies, however, and this absence reveals new directions for future research. 相似文献
999.
Poggi SH Goodwin KM Hill JM Brenneman DE Tendi E Schninelli S Spong CY 《American journal of obstetrics and gynecology》2003,189(3):786-789
OBJECTIVE: Fetal alcohol syndrome (FAS) results in stillbirth, fetal growth restriction, and mental retardation with injury attributed to oxidative stress. Our objective was to identify signal transduction pathways expressed in a model of FAS and to quantify expression of c-fos, a gene in the stress signal pathway. STUDY DESIGN: Timed, pregnant C57Bl6/J mice were injected on E8 with saline solution or alcohol. RNA was extracted from decidua and embryo 6 and 24 hours later. Microarray analysis was used to screen gene pathways. Differential gene expression was confirmed using real-time polymerase chain reaction with results presented as the ratio of c-fos concentration to that of glyceraldehyde-3-phosphate dehydrogenase (GAPDH). RESULTS: Differential gene expression between alcohol and control was noted for stress signal pathway genes including c-fos. Real-time polymerase chain reaction demonstrated that c-fos messenger RNA expression was greater in the alcohol than control decidua at 6 hours after injection (P<.01). This effect persisted at 24 hours (P<.01). There was no difference in c-fos expression in embryos whose mothers received alcohol versus control after 6 hours (P=.12) or 24 hours (P=.89). CONCLUSION: Alcohol administration during pregnancy results in differential gene expression in the stress signal pathway, particularly in c-fos. C-fos expression in the decidua increases from 6 to 24 hours after alcohol injection, but does not change in the embryo, which may contribute to alcohol-induced damage in FAS. 相似文献
1000.
Freeman R Hill S Millard R Slack M Sutherst J;Tolterodine Study Group 《Obstetrics and gynecology》2003,102(3):605-611
OBJECTIVE: To evaluate the effect of once-daily, extended-release tolterodine on urinary urgency in patients with overactive bladder. METHODS: Patients with urinary frequency (eight or more micturitions per 24 hours) and urge incontinence (five or more episodes per week) were randomized to oral treatment with tolterodine extended release 4 mg once daily (n=398) or placebo (n=374) for 12 weeks. Efficacy was assessed by use of patient perception evaluations. RESULTS: The results presented are a secondary analysis of this double-blind, placebo-controlled study. Of patients treated with tolterodine extended release, 44% reported improved urgency symptoms (compared with 32% for placebo), and 62% reported improved bladder symptoms (placebo, 48%) (both P<.001 compared with placebo). The odds of reducing urgency and improving bladder symptoms were 1.68 and 1.78 times greater, respectively, for patients in the tolterodine extended release group than for patients receiving placebo. In response to urgency, there was a more than six-fold increase in the proportion of patients able to finish a task before voiding in the tolterodine extended release group. The proportion of patients unable to hold urine upon experiencing urgency was also decreased by 58% with tolterodine, compared with 32% with placebo (P<.001). The proportion of patients reporting "much benefit" from treatment was greater for tolterodine extended release than for placebo (43% versus 24%; P<.001). The only adverse events with an incidence of greater than 5% were dry mouth, headache, and constipation, with only dry mouth markedly more frequent with tolterodine than with placebo. CONCLUSION: Tolterodine extended release has demonstrable efficacy in reducing the severity of urinary urgency and is associated with improvements in overactive bladder symptoms that are meaningful to patients. 相似文献