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The goal in improving the progestational component of oral contraceptives (OCs) is to enhance the selectivity of the progestin by achieving a high degree of contraceptive efficacy while decreasing undesirable side effects associated with existing progestational agents. The androgenic activity of current progestins results in changes in lipid metabolism, particularly decreased levels of high-density lipoprotein cholesterol (HDL), which have been associated with an increased risk of coronary heart disease (CHD). A progestin with high antiovulatory activity and minimal androgenicity would offer a clear therapeutic advantage in oral contraception. Norgestimate (NGM) is a new progestin with a unique profile of biological activity that has demonstrated a high level of selectivity in preclinical assays. The present studies were conducted to confirm clinically the low androgenic activity of NGM. Norgestimate (0.25 mg) in combination with 0.035 mg ethinyl estradiol (NGM 0.25/35) was compared with 0.30 mg norgestrel combined with 0.030 mg ethinyl estradiol (Lo/Ovral) in two multicenter clinical studies. In the first study (1,261 women), HDL levels were significantly increased from baseline levels in NGM 0.25/35 subjects but were significantly decreased in Lo/Ovral subjects. Increases in low-density lipoprotein cholesterol (LDL) levels were moderate in the NGM 0.25/35 group and pronounced in the Lo/Ovral group. A favorable lipid profile in NGM 0.25/35 subjects was also reflected in the LDL/HDL ratios, which were significantly lower in the NGM 0.25/35 subjects than in the Lo/Ovral subjects. Sex hormone binding globulin (SHBG) binds androgens, preventing clinical expression of androgenic activity. As a result, elevations in SHBG levels reduce bioactive (unbound) androgen levels and decrease the potential for androgenic side effects.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
74.
A Chapdelaine J L Desmarais R J Derman 《Revue fran?aise de gynécologie et d'obstétrique》1990,85(6):417-421
The aim for improving the progestogen component of oral contraceptives is both to increase their selectivity by obtaining a highly effective contraceptive action and to decrease the side effects related to the existing progestogens. The androgenic activity of the existing progestogens modifies the lipid metabolism, particularly a decrease in the high density lipoprotein (HDL) level, which increases the risks of cardiovascular diseases. Thus, the discovery of a progestogen with good anti-ovulatory and minimal androgenic properties would constitute an important progress in the field of oral contraception. Norgestimate (NGM) is a new progestogen presenting an exceptional profile of biological activity, and has proved to be extremely selective, as observed during the clinical trials. The studies described below have been carried out in order to confirm clinically the low androgenic activity of NGM. In two clinical trials, Norgestimate (0.25 mg) associated with 0.035 mg of ethinyloestradiol (NGM 0.25/35) was compared to norgestrel (0.30 mg) associated with 0.030 mg of ethinyloestradiol (Lo/Ovral). In the first trial (1,261 women), the following observations were made: an important increase in the HDL level compared to the base levels in the subjects taking NGM 0.25/35, and an important decrease in the HDL level in those taking Lo/Ovral. The low density lipoprotein (LDL) level increased slightly in the NGM 0.25/35 group, while a higher increase was observed in the Lo/Ovral group. Moreover, the LDL/HDL ratio translates a more favourable lipid profile in the NGM 0.25/35 group, since the values are lower than those observed for the Lo/Ovral group.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
75.
Foreign body removal has been developed as a routine radiology department service. Techniques, indications and hazards are described. 相似文献
76.
DL DSouza SB Heinze RJ Dowling 《Journal of Medical Imaging and Radiation Oncology》2006,50(3):246-248
Lung cancer is not commonly known to metastasise to the perirenal space, with only five such cases previously published. We present an unusual case of perirenal lung metastases manifesting as diffuse perinephric stranding which to our knowledge has not been described before. 相似文献
77.
Sarah E Burdall Andrew M Hanby Mark RJ Lansdown Valerie Speirs 《Breast cancer research : BCR》2002,5(2):89-7
The majority of breast cancer research is conducted using established breast cancer cell lines as in vitro models. An alternative is to use cultures established from primary breast tumours. Here, we discuss the pros and cons of
using both of these models in translational breast cancer research. 相似文献
78.
RJ Gilbertson E Harris SK Pandey P Kelly W Myers 《Archives of disease in childhood》1996,75(3):194-198
Paracetamol is the commonest agent employed in self poisoning, however it is not clear whether adolescents possess insight into the serious complications associated with its misuse. Using a one page questionnaire, the availability, usage, and knowledge of toxicity of paracetamol among 1147 American and British adolescents was assessed. Although 90% of all students recognised that paracetamol could kill, the great majority of students overestimated the lethal dose. In addition, while knowledge regarding side effects of paracetamol was poor the drug was widely available to, and used by, the study population. It is proposed that gross overestimation of the number of tablets required to kill, poor understanding of paracetamol side effects, and wide availability of the drug contribute to its frequent use in adolescent suicidal behaviour. The inclusion of some over-the-counter medications in school drug education programs in addition to tighter control of the availability of paracetamol may help reduce the problem of adolescent self poisoning. 相似文献
79.
The main purpose of this study was to compare rectal and axillary temperature measurements in African children. Altogether 573 sick children were seen in an outpatient setting in rural West Africa. Rectal and axillary temperatures were measured and the parent or guardian was asked if they thought that the child had a raised body temperature. Normal ranges were defined from an age matched population of 203 healthy children. A raised axillary temperature predicted a raised rectal temperature with a sensitivity of 98% and a specificity of 88%. The parents' impression that their child had a fever was a less sensitive (89%) and less specific (59%) indicator of raised rectal temperature. A raised axillary temperature is a good screening test for a raised rectal temperature in African children. 相似文献
80.
JR Skinner AG Stuart J O'Sullivan A Heads RJ Boys S Hunter 《Archives of disease in childhood》1993,69(2):216-220
Doppler and direct measurements of right ventricle to right atrial pressure drop were made during cardiac catheterisation on 28 occasions in 26 infants with congenital heart disease. Age was 10 days to 12 months (median 4.5 months), and weight was 3.1 to 9.0 kg (median 4.7 kg). We measured peak velocity of tricuspid regurgitation by continuous wave Doppler, and the pressure drop was calculated using the modified Bernoulli equation (delta p = 4v2). There was a high correlation (r = 0.95) between direct and Doppler measurements. Doppler values tended to underestimate the right ventricle to right atrial pressure drop, but this was not of clinical significance (mean 2 mm Hg). The 95% confidence interval for the Doppler velocity was -0.41 to +0.26 m/sec, and was consistent across the range of pressures studied. Variability between observers was tested, by two observers performing sequential paired examinations on 16 newborn babies with tricuspid regurgitation. The coefficient of repeatability was 6.3 mm Hg (95% confidence interval 4.7 to 9.5 mm Hg) or 0.26 m/sec (0.18 to 0.50 m/sec). This method of right ventricular pressure estimation, validated previously only in older children and adults, is a reproducible and accurate technique in infants with tricuspid regurgitation. 相似文献