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11.
Endothelin receptor expression in human decidua   总被引:3,自引:1,他引:3  
The endothelins are signalling peptides that act via two receptors, ET(A) and ET(B). In the human endometrium, endothelin receptors have been demonstrated in glands and stroma and have been shown to vary during the course of the menstrual cycle. The present study was undertaken to determine whether or not expression of endothelin receptors changes during pregnancy or after administration of exogenous progestagens. The expression of the receptors was correlated with the appearance of basement membrane components during decidualization of the endometrial stroma. Decidual specimens (n = 15) were obtained during the first trimester of pregnancy and 10 at term. Sixteen pairs of endometrial biopsies were obtained from women with menorrhagia before and after exposure to exogenous progestagens. A total of 15 hysterectomy specimens were used as controls for the expression of stromal basement membrane proteins in the absence of decidualization. Autoradiography was carried out with selective ligands for ET(A) ([125I]-PD 151242) and ET(B) ([125I]-BQ3020). The distribution of ligand binding was then compared with the distribution of laminin alpha2 light chain and collagen IV. ET(A), ET(B), laminin alpha2 light chain, and collagen IV were expressed in stromal decidual cells in the first trimester of pregnancy. ET(B) was also found on endometrial glandular epithelium. Quantitative macro-autoradiography and multiple regression analysis demonstrated a highly significant positive correlation (P < 0.001) between expression of ET(B) and laminin alpha2 light chain. In the third trimester qualitative examination suggested a reduction of ET(A) in the stroma. Progestagen-induced decidua exhibited a similar pattern to that found in first trimester decidua. This study has demonstrated up-regulation of ET(B) during the progesterone- dependent process of decidualization and suggests a paracrine or autocrine role for endothelins in the decidua.   相似文献   
12.
Permanent impairment of embryo development by hydrosalpinges   总被引:6,自引:9,他引:6  
Recent reports suggest a deleterious effect of hydrosalpinges on pregnancy outcome for in-vitro fertilization (IVF) and improvement following surgical treatment. We compared the effect of hydrosalpinx on pregnancy outcome in 286 patients having 348 IVF cycles and followed the development of untransferred embryos for 7 days to determine if hydrosalpinges affect oocyte quality or embryo development. The delivery rate per retrieval was significantly lower for patients with hydrosalpinx, but was restored by surgical treatment to that of patients without hydrosalpinx. However, the implantation rate per embryo transferred and normal blastulation of untransferred embryos, which were significantly decreased in patients with hydrosalpinx, and growth arrest and degeneration of untransferred embryos, which were significantly increased compared to patients without hydrosalpinx, were not restored by surgical treatment of hydrosalpinges. We conclude that surgical treatment of hydrosalpinges decreases early pregnancy loss and improves pregnancy outcome, possibly by diminishing reversible deleterious effects exerted on the endometrium. As we have seen in our laboratory, hydrosalpinges may have a permanent negative influence on ovarian function, follicular development and oocyte quality since implantation of transferred embryos and normal blastulation of untransferred embryos remain low, and in-vitro growth arrest and degeneration remain high despite surgical treatment of hydrosalpinges.   相似文献   
13.
The relationship between fecundability and month of birth was investigated in a cohort of 1526 women who married between 1802 and 1929, using only women whose first marriage occurred before the age of 35 years. On the basis of their time to pregnancy (TTP, calculated as time between wedding and first birth minus gestational length), women were categorized into two groups: fecunds (TTP up to 12 months or prenuptial conceptions, n = 1348) and subfecunds (TTP >18 months, n = 118). By use of logistic regression, cosinor functions with a period of 1 year or 6 months and variable shift and amplitude were fitted through the monthly odds of subfecunds versus fecunds. The best fitting curve was unimodal, with a zenith in September (P = 0.13 for H0: no differences). Exclusion of childless women (n = 36, minimum follow-up 5 years) from the subfecunds led to a similar curve (P < 0.01), while childless women, as compared with fecunds, showed a birth distribution that was best represented with a bimodal curve with zeniths in January and July (P = 0.06). This study provides evidence for the existence of differences in fecundability by month of birth. The cause of this relationship is unclear, but may lie in a melatonin-dependent circannual variability of the quality of the oocyte.   相似文献   
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Vascular endothelial growth factor (VEGF) is a potent angiogenic factor. VEGF gene therapy improves perfusion of ischemic myocardium in experimental models and possibly in patients with end-stage coronary artery disease. In addition to its proliferative and migratory effect on endothelial cells, it also activates and up-regulates endothelial nitric oxide synthase (eNOS). Therefore, the authors investigated coronary endothelium-dependent vasodilatation in patients before and after VEGF gene therapy. The effect of intracoronary acetylcholine infusion on coronary diameter was assessed at baseline and after 3 months follow-up in patients with end-stage coronary artery disease treated with VEGF gene and in controls scheduled for elective percutaneous transluminal coronary angioplasty (PTCA) (acetylcholine test at diagnostic angiography and before a subsequently scheduled PTCA). Five out of six VEGF patients experienced a reduction in anginal complaints. Angiographic evidence for improved collateral filling was evident in two out of six patients. The vasoconstrictive response to acetylcholine was partly converted into dilatation. In contrast, the acetylcholine response in control patients remained vasoconstrictive. In conclusion, VEGF gene therapy has an important beneficial effect on the functional characteristics of the myocardial vascular network. Therefore, this therapy can potentially play an important role in all stages of the atherosclerotic process.  相似文献   
17.
A 14-year-old nonasthmatic boy who presented with multiple skin lesions and a mediastinal tumor was found to have allergic angiitis and granulomatosis (AAG) (Churg-Strauss syndrome), with prominent involvement of the thymus. The occurrence of AAG in the thymus merits recognition because of possible confusion with a variety of other lesions characterized by proliferation of histiocytes and tissue eosinophilia that affect this organ. In addition, this case illustrates that the absence of asthma should not be used as a definitive criterion for exclusion of the diagnosis of AAG.  相似文献   
18.
Levin  DC; Gardiner  GA  Jr 《Radiology》1987,164(3):675-680
For many years, atherosclerotic coronary artery lesions have been described by angiographers only in terms of location and degree of narrowing. However, it has become apparent that coronary stenoses generally have distinct morphologic features that can be recognized at angiography and that allow them to be classified as either "simple" or "complex" plaques. Complex plaques are those characterized by ulcerated or ruptured surfaces, subintimal hemorrhage, superimposed partially occluding thrombi, recanalized thrombi, or some combination. Pathologic studies have shown a very high frequency of these lesions at sites of total thrombotic occlusion of coronary arteries. Clinical and angiographic studies have demonstrated a high frequency of such lesions in living patients with both unstable angina and acute myocardial infarction. The presence of complex stenoses has also been found to increase the risk of future myocardial infarction. Plaque morphology thus appears to significantly affect the prognosis of patients with coronary disease and should be carefully evaluated in interpretation of all coronary angiograms.  相似文献   
19.
目的:合成双-对二甲氨基苯甲醛缩二胺类希夫碱,并对其抗菌活性进行研究。方法:以对二甲氨基苯甲醛和二胺类为原料,经缩合反应,制得4种相应希夫碱。结果:结构经元素分析、红外光谱、核磁共振谱确定,4种化合物均未见文献报道,抗菌活性测试表明,它们具有一定抗菌活性。结论:乙酸是催化剂,对缩合反应有利,希夫碱化合物具有一定抗菌活性。  相似文献   
20.
  • 1 It was first shown several years ago that the rostral part of the ventrolateral medulla (VLM) contains a high density of receptor binding sites for angiotensin II (AngII). In the present paper we briefly review recent studies aimed at determining the actions of both exogenous and endogenous angiotensin peptides in the rostral VLM, as well as their specific sites of action.
  • 2 The results of these studies have shown that angiotensin peptides can excite pressor and sympathoexcitatory neurons in the rostral VLM, but do not appear to affect non-cardiovascular neurons in this region.
  • 3 It is known that pressor neurons in the rostral VLM include both catecholamine and non-catecholamine neurons. There is evidence that, at least in conscious rabbits, both of these types of neurons are activated by AngII. The specific endogenous angiotensin peptide or peptides that affect pressor neurons in the rostral VLM have not yet been definitively identified.
  • 4 It is also possible that different angiotensin peptides may have different effects on pressor neurons in the rostral VLM, mediated by different receptors. Further studies will be needed to define these different functions as well as the specific receptors and cellular mechanisms that subserve them.
  相似文献   
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