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Severe adverse effects during the use of ovulation inhibitors occur mostly in women who have an elevated risk for the development of certain diseases owing to hereditary or acquired factors. By means of a careful personal or family history analysis as well as specific laboratory examinations, an existing predisposition may frequently be diagnosed and the individual risk associated with the use of oral contraceptive inhibitors may be estimated. The present contribution describes the potential effects of treatment with ovulation inhibitors on women with thrombophilia, cardiovascular disease, diabetes mellitus, dyslipidemia, overweight or underweight, tumors, psychiatric and neurological diseases and autoimmune disease. The hormonal methods and non-hormonal alternatives available for contraception are elucidated according to existing lesions and risk factors and the advantages and disadvantages are discussed. 相似文献
63.
M Bernasconi P N Chhajed F Gambazzi L Bubendorf H Rasch S Kneifel M Tamm 《The European respiratory journal》2006,27(5):889-894
There are no data available combining transbronchial needle aspiration (TBNA) of mediastinal lymph nodes and positron emission tomography (PET) in the staging of nonsmall cell lung cancer (NSCLC). The aim of the current study was to determine if these two methods can enhance the negative predictive value of the individual modality alone, for a specific lymph node station, and if this integrated approach can reduce the number of mediastinoscopies. A total of 113 patients with enlarged mediastinal lymph nodes (> or = 1 cm), who underwent both TBNA and PET scanning, were included. In 51 patients, histopathology, confirmed by surgical lymph node dissection, was compared with PET results and TBNA. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy to detect malignant lymphadenopathy was 68 (13/19), 89 (119/134), 46 (13/28), 95 (119/125) and 86% (132/152) for PET, respectively; 54% (6/11), 100 (53/53), 100 (6/6), 91 (53/58) and 92% (59/64), respectively for TBNA; and 100 (11/11), 94 (50/53), 79 (11/14), 100 (50/50) and 95 (61/64) for combined TBNA and PET, respectively. Combination of transbronchial needle aspiration and positron emission tomography has the potential to allow adequate mediastinal staging of nonsmall cell lung cancer with enlarged lymph nodes in most patients without the need for mediastinoscopy. 相似文献
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A new semi-empirical formula for the evaluation of (n,(3)He) reaction cross-sections at the energy of 14.6 and 20 MeV is presented. Formula was derived using the analytical expression for the evaluation of the (3)He spectrum within the frame of pre-equilibrium exciton model. The systematics obtained is compared with the empirical formula for the (n,(3)He) reaction cross-section. 相似文献
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Paul A Dabisch Emily A Davis Michael S Horsmon Robert J Mioduszewski 《Journal of ocular pharmacology and therapeutics》2006,22(5):323-332
The organophosphorous nerve agent sarin (GB) and the carbamate pyridostigmine bromide (PB) both inhibit acetylcholinesterase (AChE), leading to overstimulation of muscarinic receptors. Both GB and PB produce miosis through stimulation of ocular muscarinic receptors. This study investigated 2 hypotheses: (1) that the miotic response to PB would decrease following repeated injections; and (2) that repeated administration of PB would result in tolerance to the miotic effect of GB vapor. Rats were injected intramuscularly with saline, 0.04 mg/kg, 0.5 mg/kg, or 1.4 mg/kg of PB twice daily for 8 consecutive days. After day 3, animals injected with 1.4 mg/kg PB developed miotic tolerance. Twenty-four (24) h following the final PB injection, the rats were exposed to GB vapor (4.0 mg/m(3)). A similar magnitude of miosis was observed in all groups after GB exposure. However, the rate of recovery of pupil size in animals pretreated with 0.5 and 1.4 mg/kg PB was significantly increased. Twenty (20) h following exposure to GB vapor, the pupils of animals pretreated with 1.4 mg/kg PB had recovered to 77% +/- 4% of their pre-exposure baseline, whereas the saline-injected controls had recovered to only 52% +/- 2% of their pre-exposure baseline. The increased rate of recovery does not appear to be a result of protection of pupillary muscarinic receptors by the higher doses of PB, as there was no longer PB present in the animal at the time of GB exposure. These results demonstrate the development of tolerance to the miotic effect of PB following repeated exposures, and also suggest that cross-tolerance between PB and GB occurs. However, because the magnitude of the response was not reduced, the PB pretreatment and its associated miotic cross-tolerance does not appear to diminish the effectiveness of miosis as a biomarker of acute exposure to nerve agent vapor. 相似文献