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Raymond EG Chen PL Condon S Luoto J Barnhart KT Creinin MD Poindexter A Wan L Martens M Schenken R Blackwell R 《Contraception》2005,72(6):438-442
OBJECTIVE: To examine the acceptability of five nonoxynol-9 (N-9) spermicides. METHODS: We analyzed data from a randomized trial of five products, including three gels containing different amounts of N-9 per dose, a film and a suppository. In the trial, 1536 participants were asked to use the assigned spermicide for 7 months and to complete questionnaires 4 weeks after admission and at discontinuation. RESULTS: Overall, 43% of participants liked their spermicide "very much." This proportion was higher in the three gel groups than in the suppository and film groups. Difficulty with insertion, messiness and discontent with timing of insertion were common complaints in all groups. After adjustment for selected baseline factors, acceptability on the first questionnaire was not related to duration or consistency of subsequent spermicide use or to subsequent time to pregnancy. CONCLUSIONS: In this study, all five spermicides were considered acceptable by most users. Acceptability did not appear to influence spermicide use or pregnancy risk. 相似文献
74.
Interferon-alpha (IFN) is widely used in the treatment of certain cancers and viral infections, including hepatitis C (HCV). Unfortunately, depression is a common side effect of IFN therapy, affecting approximately a third of HCV patients receiving IFN therapy. Studies have shown that selective serotonin reuptake inhibitors (SSRIs) can effectively treat IFN-induced depression in only 63-75% of cases. For the remaining percentage, depression often necessitates dose reduction of or discontinuation from IFN therapy. Emerging evidence indicates that IFN may cause depression by affecting brain serotonin. IFN has been shown to increase serotonin reuptake and to decrease serotonin synthesis. We hypothesize that SSRIs are not fully effective because they affect only serotonin reuptake, not serotonin synthesis, and that effective treatment must address both uptake and synthesis. 5-Hydroxytryptophan (5-HTP) effectively increases central nervous system synthesis of serotonin. It is the immediate precursor of serotonin and is widely available as a dietary supplement, which is well absorbed after an oral dose. Several double-blind studies have shown 5-HTP to be effective in the treatment of nondrug-induced depression. We hypothesize that patients who become depressed on IFN will respond to the synergistic combination of SSRIs plus 5-HTP. 相似文献
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Culligan PJ Kubik K Murphy M Blackwell L Snyder J 《American journal of obstetrics and gynecology》2005,192(2):422-425
OBJECTIVE: The purpose of this study was to compare the efficacy of chlorhexidine and povidone iodine for cleansing the operative field for vaginal surgery. STUDY DESIGN: This was a randomized controlled trial that compared 10% povidone iodine and 4% chlorhexidine gluconate as surgical scrubs. Our primary end point was the proportion of contaminated specimens (defined as total bacterial colony counts of >/=5000 colony-forming units) per group found throughout the surgical procedures. All patients received standard infection prophylaxis that included preoperative intravenous antibiotics. Immediately before antibiotic administration and baseline aerobic and anaerobic cultures of the vaginal flora were obtained, which were followed by cultures at 30 minutes after the surgical scrub and hourly thereafter throughout each patient's surgery. RESULTS: A total of 50 patients were enrolled between October 2002 and September 2003. There were no differences between the povidone iodine (n = 27) and chlorhexidine (n = 23) groups with respect to age, race, exogenous hormone use, body mass index, gravity, parity, preoperative mean colony counts, or operative time. Among the first set of intraoperative specimens (which were obtained 30 minutes after the surgical scrub), 63% of the cultures (17/27) from the povidone iodine group and 22% of the cultures (5/23) from the chlorhexidine group were classified as contaminated ( P = .003; relative risk, 6.12; 95% CI, 1.7, 21.6). Subsequent cultures failed to demonstrate significant differences. CONCLUSION: Chlorhexidine gluconate was more effective than povidone iodine in decreasing the bacterial colony counts that were found in the operative field for vaginal hysterectomy. 相似文献
77.
An internet-based randomized, placebo-controlled trial of kava and valerian for anxiety and insomnia
The herbal extracts kava and valerian are the leading dietary supplements used in the self-management of anxiety and insomnia, respectively. There is limited evidence to support their effectiveness for these common symptoms. The Internet has been used to a limited extent for research, but it is not known whether randomized controlled trials can be conducted entirely using Internet technology. We performed a randomized, double-blind, placebo-controlled trial using a novel Internet-based design to determine if kava is effective for reducing anxiety and if valerian is effective for improving sleep quality. E-mail recruitment letters and banner advertisements on websites were used to recruit a large pool of interested participants (1551) from 45 states over an 8-week period. Participants were first asked to read study information, complete an online informed consent process, and undergo electronic identity verification. In order to be eligible for the study, participants were required to have 1) anxiety as documented by scores of at least 0.5 standard deviations above the mean on the State-Trait Anxiety Inventory State subtest (STAI-State) on 2 separate occasions, and 2) insomnia, defined as a "problem getting to sleep or staying asleep over the past 2 weeks." We randomly assigned 391 eligible participants to 1 of the following 3 groups, and mailed 28 days' supply: kava with valerian placebo (n = 121), valerian with kava placebo (n = 135), or double placebo (n = 135). The primary outcome measures were changes from baseline in anxiety (STAI-State questionnaire) and insomnia (Insomnia Severity Index [ISI]) compared with placebo. Participants receiving placebo had a 14.4 point decrease in anxiety symptoms on the STAI-State score and an 8.3 point decrease in insomnia symptoms on the ISI. Those receiving kava had similar reductions in STAI-State score (2.7 point greater reduction in placebo compared with kava; 95% confidence interval [CI], -0.8 to +6.2). Those receiving valerian and placebo had similar improvements in sleep (0.4 point greater reduction in the placebo than the valerian group; 95% CI, -1.3 to +2.1). Results were similar when limited to the 83% of participants who adhered to study compounds for all 4 weeks. Neither kava nor valerian relieved anxiety or insomnia more than placebo. This trial demonstrates the feasibility of conducting randomized, blinded trials entirely via the Internet. 相似文献
78.
Tavss EA Fisher SW Campbell S Bonta Y Darcy-Siegel J Blackwell BL Volpe AR Miller SE 《American journal of dentistry》2004,17(1):61-70
PURPOSE: To describe the development of a new dentin hypersensitivity treatment, Colgate Sensitive Maximum Strength dentifrice, containing 5% potassium nitrate as the anti-hypersensitivity active agent. The objective was to develop a home-use hypersensitivity dentifrice that would be superior to the market leader, improving on what is available, which also contains 5% potassium nitrate as the anti-hypersensitivity active agent. METHODS: In vivo (clinicals, taste evaluation and rat caries), in vitro (potassium flux) and analytical (rheology, dispensed volume, scanning electron microscopy, electron scanning chemical analysis and radioactive dentin abrasion) methods were performed. RESULTS: The objective was accomplished with the development of a new activated silica technology that resulted in enhanced potassium ion activity. In vitro documentation, supported by clinical studies, demonstrated that the resulting formula is more effective than the market leader for relief of hypersensitivity pain. Fast pain relief in less than 2 weeks and long-lasting protection against pain with regular use have also been clinically documented. Furthermore, FDA-required in vivo and in vitro studies indicate that this formula, which contains 0.45% stannous fluoride (1100 ppm fluoride) as the anti-caries active agent, is effective against caries. Good taste, acceptable rheology, acceptable abrasivity, and cosmetic and chemical stability have all been engineered into this unique dentin hypersensitivity treatment. In summary, a highly efficacious consumer friendly treatment for dentin hypersensitivity has been developed. 相似文献
79.
Bedoyan JK Blackwell SC Treadwell MC Johnson A Klein MD 《Pediatric surgery international》2004,20(3):170-176
This retrospective study reviews the medical records of 77 fetuses and babies with congenital diaphragmatic hernia (CDH) referred to two hospitals in Detroit from 1986 through 2000. The aims were to examine the effects on outcome of multiple variables, especially the type of CDH, associated anomalies, and ultrasound prognostic parameters. Ultrasound measurements of head (HC), chest (CC), and abdominal circumferences (AC) were obtained from videotapes. ANOVA and chi-square analysis were used to determine statistical significance between groups and proportions. Eighty-nine percent (65/73) of pregnancies resulted in live births, and 54% (35/65) of patients survived past 30 days. Liveborn patients with low APGAR scores were less likely to survive. Forty-three percent (30/70) had major associated anomalies, with cardiac anomalies constituting about 52% (33/64) of the major associated anomalies. Seventy percent of patients with isolated CDH survived versus 36% of patients with both CDH and cardiac anomalies. Sixty-seven percent (8/12) of fetuses antenatally diagnosed before 25 weeks of gestation survived past 30 days of birth. The survival rate of right-sided CDH with liver herniation was 80% (8/10), compared with 29% (4/14) for left-sided CDH with liver herniation (p=0.088). There was a significant linear relationship (r=0.603, p =0.029) between CC/AC and CC/HC among patients with CDH; survivors had higher CC/AC and CC/HC values than nonsurvivors. These results support the utility of CC/AC and CC/HC measurements and the presence of liver herniation as important prognostic factors that can be used in antenatal counseling and in planning clinical trials. 相似文献
80.
Mehta SH Bujold E Blackwell SC Sorokin Y Sokol RJ 《American journal of obstetrics and gynecology》2004,190(6):1604-7; discussion 1607-9
OBJECTIVE: This study was undertaken to examine the relationship between labor abnormalities and shoulder dystocia in nulliparous women. STUDY DESIGN: Nulliparous women whose delivery was complicated by shoulder dystocia were studied and compared with a control group selected based on the best possible match for race, labor type (spontaneous or induced), and birth weight. The duration of first and second stage of labor, as well as the rates of labor progress, were calculated and compared between groups. RESULTS: During this 4-year study period, there were 8010 nulliparous singleton deliveries of which 65 (0.8%) were complicated by shoulder dystocia. Compared with controls, there was no difference in the rate of cervical dilation in the active phase of the first stage of labor. In the shoulder dystocia group, more patients had a second stage of labor greater than 2 hours (22% vs 3%; P <.05) and had operative vaginal deliveries (26% vs 1.5%; P <.001). In shoulder dystocia cases with birth weight greater than 4000 g, 33% had a second stage of labor greater than 2 hours. CONCLUSION: In our population, the combination of fetal macrosomia, second stage of labor longer than 2 hours and the use of operative vaginal delivery were associated with shoulder dystocia in nulliparous women. 相似文献