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81.
Ketoprofen is a photolabile drug. The aim of the present study was to compare the bioavailability of ketoprofen in a photo-stabilised formulation with a gel without photoprotection using a new dermatopharmacokinetic tape-stripping model and an established ex vivo penetration method using human skin. Analyses of the stratum corneum showed that during the first 45 min about 12 microg/cm2 ketoprofen was absorbed into the skin from the formulations. The area under the ketoprofen content-time curve (AUC0-6 h) for the ratio photo-stabilised gel/transparent gel was 73% with a 90% confidence interval (CI) 65-83. The rate of penetration of ketoprofen through isolated skin was approximately 0.2 microg/cm2 h for both formulations. AUC0-36 h for the ratio was 84% with 90% CI 64-105. Thus, the two methods did not disagree in terms of relative efficacy of the two gels. However, the difference obtained in vivo was statistically significant, whereas no significant data arise from the ex vivo study. Comparing the amount of ketoprofen in the skin after 45 min with the amount penetrated through the excised skin during 36 h, suggests a change in the thermodynamic activity of ketoprofen during the exposure. A supersaturated formulation may well have been formed initially due to evaporation of ethanol.  相似文献   
82.
AIM: To assess changes in sexual behaviour among students at a high school in Denmark from 1982 to 2001. METHODS: An anonymous self-administered questionnaire was used to compare data from three identical cross-sectional surveys performed in 1982, 1996, and 2001. RESULTS: Girls: More girls reported their first sexual intercourse before their 16th birthday in 2001 (42%) than in 1996 (29%) In 1982 it was also 42% (Chi-square for trend: p = 0.003). Fewer girls with no regular partner used condoms for their personal protection in 2001 (2%) than in 1996 (9%) and 1982 (0%) (Chi-square for trend p = 0.016). The proportion of girls with no regular partner who considered protection from sexually transmitted disease important for their choice of contraception was 39% in 2001 compared with 71% in 1996 and only 10% in 1982 (Chi-square for trend: p < 0.0001).Boys: More boys reported sexual debut before their 16th birthday in 2001 (40%) than in 1996 (37%) and 1982 (24%) (Chi-square for trend: p = 0.023). For boys with no regular partner, condom was preferred for personal protection by 85% in 2001, 91% in 1996 and 61% in 1982 (Chi-square for trend p = 0.007). Protection against sexually transmitted infection declined, especially among boys with no regular partner, from 51% in 2001 to 72% in 1996 and 21% in 1982 Chi-square for trend: p < 0.0001).The tendency towards earlier sexual debut and less use of safe sex practices to protect against sexually transmitted infections (STI) was accompanied by a rise in the number of detected STIs during this period. CONCLUSIONS: The period from 1982 to 1996 during which sexual attitudes were directed toward safer sex seems to have given way to a reverse trend in the period from 1996 to 2001. These findings may have significant implications for health care authorities organising preventive strategies for healthy adolescents.  相似文献   
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84.
BACKGROUND: Vitamin C can be metabolized to oxalate. Case reports have suggested an association between IV vitamin C and urinary oxalate excretion. Recently, the US Food and Drug Administration required the dose of vitamin C in IV multivitamin preparations to be increased from 100 mg to 200 mg/d. We compared the urinary oxalate excretion level in stable home total parenteral nutrition (TPN) patients receiving both doses of vitamin C. METHODS: Each participant provided a 24-hour urine sample for oxalate determination on the vitamin C dose (100 mg/d), and again after at least 1 month on the increased vitamin C dose (200 mg/d). A 2-day diet diary was completed covering the day before and the day of the urine collection and was analyzed for oxalate and vitamin C content. Comparisons were made using Student paired t test and Wilcoxon signed rank. RESULTS: Thirteen patients (7 males/6 females) aged 63.1 +/- 12.2 years who had no history of nephrolithiasis and had received TPN for 55.9 +/- 78.8 months were enrolled. The most common indication for TPN was short bowel syndrome (38.5%). Eight patients had an intact colon. Urinary oxalate excretion increased on the 200-mg vitamin C dose, from 0.34 +/- 0.13 to 0.44 +/- 0.17 mmol/d (mean increase = 0.10 mmol/d; p = .04; 95% confidence interval 0.004 to 0.19 mmol/d). Oral intake of vitamin C and oxalate did not differ between the 2 collection periods. CONCLUSIONS: In therapeutically used doses, IV vitamin C increases urinary oxalate excretion, potentially predisposing susceptible individuals to nephrolithiasis. This factor should be considered in patients receiving home TPN.  相似文献   
85.
BACKGROUND: The aim of this study was to evaluate how women experience the gynecologic examination and to assess possible factors associated with experiencing discomfort during the gynecologic examination. METHODS: Consecutive patients visiting the Department of Obstetrics and Gynecology at Glostrup County Hospital, Denmark, were invited to participate in the study, and received a postal questionnaire that included questions about the index visit, obstetric and gynecologic history and sexual abuse history. The response rate was 80% (n = 798). The degree of discomfort during the gynecologic examination was indicated on a scale from 0 to 10. Experiencing discomfort was defined as a score of 6 or more, based on the 75th percentile. RESULTS: Discomfort during the gynecologic examination was strongly associated with a negative emotional contact with the examiner and young age. Additionally, dissatisfaction with present sexual life, a history of sexual abuse and mental health problems such as depression, anxiety and insomnia were significantly associated with discomfort. CONCLUSION: The emotional contact between patient and examiner seemed to have great importance when focusing on discomfort during the gynecologic examination. Furthermore, we found that discomfort was associated with a number of factors that are seldom known to the gynecologists, such as sexual abuse history, mental health problems and patients' sexual life. Gynecologists need to focus on the emotional contact and to reevaluate issues for communication before the examination.  相似文献   
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87.
Today, clothing and clothing systems for cleanrooms are mainly tested with regard to material properties such as particle generation, particle filtration, and resistance to wear. The dispersal chamber or "body-box" has been used for studying the protective efficacy of clothing systems in use, for example by Hoborn in 1981 (1) and Whyte and Bailey in 1985. A modified dispersal chamber has recently been installed at KTH. Tests and comparative studies have been performed in the dispersal chamber on selected clothing systems. The latest tests have been performed in two parts. In Part 1, each person performed 12 sequences dressed in new, modern cleanroom clothing systems with small variations, such as with and without goggles, different face masks, and different sizes of hoods. In Part 2, each person performed six test sequences with new, modern cleanroom clothing systems with variations in fabrics, and as a comparison, two sequences with pharmaceutical clothing system and surgical clothing system, respectively. The results are given in total number of airborne particles (> or = 0.5 microm per cubic meter) and airborne aerobic CFU per cubic meter. Statistical evaluations of the results have been performed. The source strengths of the contamination source people wearing modern cleanroom clothing systems have been estimated.  相似文献   
88.
89.
Thrombospondin-1 (TSP-1) is a potent antiangiogenic factor that has been shown to inhibit tumor growth by preventing endothelial cells from responding to a wide variety of angiogenic stimulators. We have demonstrated previously that D-12 primary tumors (human melanoma xenografts) suppress the growth of their spontaneous pulmonary micrometastases by secreting TSP-1 into the blood circulation. The same tumor model was used in the present work to study antitumor effects of combined radiation therapy and antiangiogenic treatment with TSP-1. Curative radiation treatment of D-12 primary tumors resulted in rapid growth of previously dormant micrometastases. Growth of dormant micrometastases could be prevented by treating the host mice with exogenous TSP-1 after the radiation treatment. Treatment with exogenous TSP-1 after subcurative radiation treatment reduced the growth rate of recurrent primary tumors in addition to suppressing metastatic growth. TSP-1 suppressed tumor growth at both primary and metastatic sites by inducing apoptosis in tumor-associated microvascular endothelial cells. Treatment with exogenous TSP-1 before radiation treatment enhanced the antitumor effect of the radiation treatment. The radiopotentiation by TSP-1 involved at least two distinctly different mechanisms, i.e., TSP-1 reduced the fraction of radiobiologically hypoxic parenchymal tumor cells and increased the radiation sensitivity of the tumor microvasculature by promoting radiation-induced endothelial cell apoptosis. In conclusion, the present preclinical study showed that TSP-1 has antiangiogenic, antimetastatic, and radiopotentiating properties that merit additional investigation in clinical studies.  相似文献   
90.
BACKGROUND: The authors assessed the prognostic significance of abnormal cyclin dependent kinase inhibitor (CDKI) expression in adenocarcinomas of the uterine cervix. METHODS: Population-based, archival material from patients with International Federation of Gynecology and Obstetrics (FIGO) Stage I and II cervical adenocarcionmas from 2 5-year periods (1976-1980, n = 82 patients; 1986-1990, n = 142 patients) was examined for expression of p21(WAF1), p27(Kip1), and p16(INK4/MTS1) using immunohistochemical techniques. RESULTS: Rates of tumors with low levels of nuclear expression of p27 and p16 were lower during the period 1976-1980 (P < 0.01), suggesting bias due to unbuffered formalin. Analyses that were restricted to patients from 1986-1990 showed positive associations between all three CDKIs (P < 0.05). Low p16 expression was associated with higher FIGO stage (P = 0.01), age older than 55 years (P = 0.01), and deep invasion (P = 0.003). No significant associations with stage, age, or histopathologic parameters were found for p21 or p27. Significant associations with tumor differentiation were not seen for any CDKI. Kaplan-Meier plots showed diverging survival curves for p21 and p27 expression, but the differences were not significant. In multivariate analysis, low p27 expression and high p16 expression were strong predictors of a poor prognosis (p27: < 40% nuclear staining; P = 0.001; hazard ratio, 3.18; p16: < 40% nuclear staining; P < 0.001; hazard ratio, 0.16). Low p27 expression was of prognostic significance only if it was analyzed together with p16 expression. Further evaluation indicated that patients with different phenotypic p27/p16 combinations may have different outcomes. CONCLUSIONS: Aberrant expression patterns of CDKIs were predictors of prognosis for patients with FIGO Stage I or II cervical adenocarcinoma. Analysis of CDKI expression in this patient group may prove clinically useful.  相似文献   
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