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51.
5-HT1B receptors were discovered in human nasal mucosa using immunocytochemistry. Strong immunoreaction was seen around small blood vessels mainly confined to the smooth muscle cell layer. In contrast, no immunoreaction for 5-HT1D was seen. The possibility of local release in connection with specific target receptors suggests a role for 5-HT in the regulation of vascular tone, glandular secretion and epithelial functions and that 5-HT1B receptor agonists may be of clinical importance. 相似文献
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Exercise testing in the magnetic resonance (MR) scanner is difficult because of space restriction and movement artefact, which limit its use in the investigation of patients with suspected coronary artery disease. Pharmacological stress, however, can be used as a substitute for exercise. Therefore, a patient with angina underwent MR ventricular wall motion studies before and after intravenous dipyridamole. Reversible abnormal regional contraction of the myocardium was demonstrated and correlated with a reversible perfusion defect on subsequent thallium myocardial perfusion imaging and a blocked artery at coronary angiography. A clinically useful investigative procedure may be developed. 相似文献
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Effect of parental age on fertilization and pregnancy characteristics in couples treated by intracytoplasmic sperm injection 总被引:11,自引:5,他引:6
Spandorfer SD; Avrech OM; Colombero LT; Palermo GD; Rosenwaks Z 《Human reproduction (Oxford, England)》1998,13(2):334-338
The purpose of this study was to investigate any influence of maternal
and/or paternal age on gamete characteristics and pregnancy outcomes in
intracytoplasmic sperm injection (ICSI) cycles. In all, 821 consecutive
ICSI cases were analysed retrospectively. While a significant linear
decline in semen volume was detected, no significant differences in the
concentration, motility or morphology of the spermatozoa were found with
paternal ageing. A significant decline in the number of oocytes retrieved
and the number of mature oocytes obtained was found with advancing maternal
age. An increase in the occurrence of digyny was noted with parental
ageing, while no difference in single or bipronuclear fertilization was
found. Older women had a decreased incidence of single pronucleus formation
and an increase in digyny, but no significant difference in the percentage
of oocytes that underwent two-pronuclear fertilization was detected with
regard to maternal ageing. Pregnancy outcomes were not influenced by the
age of the male partner, while a strong negative correlation was found with
maternal ageing. To better analyse male partner ageing as a factor
affecting pregnancy outcome, we analysed a subgroup of patients with a
female partner aged <35 years who underwent ICSI. No paternal influence
on ICSI pregnancy outcome was found in this subgroup of patients. We
conclude that the influence on pregnancy outcome after ICSI is related
mostly to maternal and not paternal age.
相似文献