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11.
性激素对大白鼠胃粘液分泌的影响   总被引:2,自引:0,他引:2  
赵逵  刘世强 《动物学报》1994,40(2):149-154
通过雄、雌性大鼠去势,怀孕鼠,以及肌肉注射性激素的方法,观察内,外源性激素对胃粘液分泌的影响,采用Alcian blue与胃液和胃壁粘液中糖蛋白结合的方法进行胃粘液测定,结果表明:雄、雌鼠胃粘液分泌无性别差异,去势夺雄、雌鼠胃粘液分泌无明显影响;怀孕鼠胃粘液分泌增加,丙酶睾酮对去势雄、雌鼠胃粘液分泌无影响,而戊酸雌二醇和孕酮可增加胃粘液分泌,提示:怀孕鼠胃粘液分泌的增加可能与雌激素和孕激素分泌增多  相似文献   
12.
We have recently established a rhesus monkey model of chronic Pseudomonas aeruginosa (PA) endobronchitis by bronchoscopic instillation of PA-embedded agar beads. All experimental animals developed chronic neutrophilic endobronchitis similar to chronic PA endobronchitis in cystic fibrosis (CF). Histopathologic studies further confirmed similarities to chronic PA endobronchitis in CF, including marked peribronchial inflammation, epithelial damage, presence of degraded cilia and ciliary abnormalities, appearance of PA bacterial clusters, mucosal hyperplasia, goblet cell hypertrophy/hypersecretion, airway obstruction, alveolar abnormalities, bronchiectasis, and fibrosis.  相似文献   
13.
14.
摘要 目的:探讨游离睾酮指数(FAI)联合血清促性腺激素平抑因子(GnSAF)、性激素结合球蛋白(SHBG)对多囊卵巢综合征(PCOS)不孕患者体外受精-胚胎移植(IVF-ET)治疗妊娠结局的预测价值。方法:选取2020年1月~2022年6月湖南省妇幼保健院生殖医学中心收治的197例PCOS不孕患者为PCOS组,根据IVF-ET治疗妊娠结局分为妊娠失败组和妊娠成功组,另选取同期68名体检健康妇女为对照组。收集PCOS不孕患者临床资料,计算FAI并检测血清GnSAF、SHBG水平。采用单因素和多因素Logistic回归分析PCOS不孕患者IVF-ET治疗妊娠结局的影响因素,采用受试者工作特征(ROC)曲线分析FAI和血清GnSAF、SHBG对PCOS不孕患者IVF-ET治疗妊娠结局的预测价值。结果:PCOS组FAI和血清GnSAF水平高于对照组,SHBG水平低于对照组(P<0.05)。197例PCOS不孕患者IVF-ET治疗妊娠成功率为51.27%(101/197)。单因素分析显示,妊娠失败组体质指数、黄体生成素(LH)、LH/促卵泡生成素(FSH)、睾酮、抗苗勒管激素(AMH)、FAI、GnSAF高于妊娠成功组,FSH、受精率、优胚率、SHBG低于妊娠成功组(P<0.05)。多因素Logistic回归分析显示,体质指数增加和LH、LH/FSH、AMH、FAI、GnSAF升高为PCOS不孕患者IVF-ET治疗妊娠失败的独立危险因素,SHBG升高为其独立保护因素(P<0.05)。ROC曲线分析显示,FAI和血清GnSAF、SHBG联合预测PCOS不孕患者IVF-ET治疗妊娠结局的曲线下面积大于FAI、GnSAF、SHBG单独预测。结论:FAI和血清GnSAF、SHBG水平联合预测PCOS不孕患者IVF-ET治疗妊娠结局的价值较高。  相似文献   
15.
双单抗的免疫层析一步法用于早妊诊断的研究   总被引:2,自引:0,他引:2  
在试管式、微孔式和斑点式的酶免测定法测定人绒毛膜促性腺激素(HCG)的基础上,发展了应用双单克隆抗体的免疫层析一步法测定HCG。此法用胶体金标记抗βHCG单克隆抗体,将抗αHCG单克隆抗体包被在硝酸纤维素膜上。无需分离步骤,特别是在进行测定时除加入样品外无需再加任何试剂,此方法特别迅速、简便,2~5min即可得结果。凡HCG浓度>25IU/L的样品可得到阳性结果。在人体血或尿中可能出现的高浓度的干扰物质,如抗坏血酸、乙酰水杨酸、雌二醇、蛋白质、胆红素、甘油三酯等对本测定均无干扰作用,在促黄体激素(LH)浓度高达500IU/L时仍与HCG没有交叉反应。能进行测定的最高值大于300IU/ml,这表示,当HCG浓度达到妊娠期的最高值时仍不会有假阴性结果。  相似文献   
16.
BackgroundResearch to date suggests that nickel affects not only the metabolism of vitamin B12 but also folates and thus may affect hematopoiesis processes.ObjectiveThe aim of the study was to examine the relationship of nickel (Ni) status to red blood cell (RBC) parameters and serum vitamin B12, folate and homocysteine concentrations in the course of normal pregnancy and in pregnant women with anemia.MethodsThe study included fifty-three pregnant women recruited to the study from the Lower Silesia region of Poland, 17 % of whom developed anemia. Nickel concentration was determined in urine, whole blood and food samples by atomic absorption spectrometry. At the same time as the food and urine samples were taken, blood was also collected for the determination of RBC parameters and serum vitamin B12, homocysteine and folate concentrations.ResultsThe median reported Ni intake, and the urinary and whole blood nickel contents for the studied pregnant women for the first trimester were respectively – 162.46 μg/day, 3.98 μg/L and 3.32 μg/L; for the second trimester – 110.48 μg/day, 6.86 μg/L and 1.04 μg/L; and for the third trimester – 132.20 μg/day, 3.41 μg/L and 0.70 μg/L. With regard to Ni concentration in whole blood (p = 0.0204) and in urine (p = 0.0003), the differences in the values for individual trimesters were statistically significant. The whole blood Ni level was significantly higher (9.28 vs 3.62 μg/L, p = 0.0114), while the concentration of homosysteine was significantly lower (4.09 vs 5.04 μmol/L, p = 0.0165) in pregnant women with anemia compared to those without anemia. The whole blood Ni concentration was negatively correlated with almost all RBC parameters in non-anemic pregnant women.ConclusionsNi status changes with the development of normal pregnancy, and in the case of anemia, an increase in Ni concentration in whole blood is observed. The demonstrated correlations between the Ni status in pregnant women and RBC parameters as well as serum vitamin B12 and folate concentrations suggest that nickel is associated with the methionine–folate cycle, iron homeostasis and bacterial synthesis of vitamin B12 in humans.  相似文献   
17.
Colony breeding records were analyzed in order to obtain information on pre- and neonatal survival in chimpanzees. Biweekly urinary chorionic gonadotrophin testing appeared suitable for determining pregnancy age. The probability of pregnancy termination was low (0.008 per 10 days) to a pregnancy age of 180 days. Between the ages of 180-210 days it was 0.080 per 10 days, and it steadily increased to one per 10 days after 240 days of age. There were no livebirths before 190 days of pregnancy age. Thereafter, the probability of a delivery to be a livebirth rapidly increased to about 0.90 after 210 days of pregnancy age. Infant mortality was less than 0.026 during the first two years of life.  相似文献   
18.
《Reproductive biology》2020,20(4):568-572
SARS-CoV-2 is a new virus, to which herd immunity has not yet developed and both molecular and serological testing are not without flaws. The virus evokes a state of severe and widespread inflammation, and stimulates both innate and adaptive immune response. The angiotensin-converting enzyme 2 (ACE2), which acts as the SARS-CoV-2 receptor, is present in endothelial cells and has been noted within the human placenta. There are questions about whether pregnancy would increase the susceptibility of pregnant women to COVID-19 and disease severity within this population. In this report, we highlight physiological and immune/inflammatory considerations that may explain the susceptibility and disease pathology in response to SARS CoV-2 during pregnancy, explore testing considerations in asymptomatic individuals, discuss the potential role and of placental ACE2 receptor in the pathogenesis of COVID-19 in pregnancy and in pregnancy outcomes, and finally share our perspective with respect to an urgently needed change concerning involvement of pregnant women in research addressing COVID-19.  相似文献   
19.
目的探究妊娠晚期阴道B族链球菌(group B Streptococcus,GBS)的感染对肠道菌群和妊娠结局的影响。方法选取2018年3月至2019年11月大连市中心医院孕检并分娩的妊娠妇女744人为对象,调查并统计B族链球菌的感染率;筛选有和没有B族链球菌感染妊娠妇女各47人,调查不良妊娠结局的发生率;选取信息匹配的妊娠晚期阴道B族链球菌感染和未感染的妊娠妇女,采集粪便样本,提取菌群DNA,用16S rDNA方法分析菌群变化。结果744名妊娠妇女中B族链球菌检出49例,感染率为6.59%;B族链球菌感染组总的不良妊娠发生比例为76.6%,正常组发生比例为27.7%(χ^2=5.491,P<0.05)。B族链球菌感染组妊娠妇女胎膜早破(χ^2=16.177,P<0.01)、难产(χ^2=21.134,P<0.01)和羊水异常(χ^2=22.989,P<0.05)的发生率与未感染组比较显著增高。B族链球菌感染组妊娠妇女肠道菌群发生显著变化。结论妊娠晚期阴道B族链球菌的感染可能引起肠道菌群紊乱,增加不良妊娠结局。  相似文献   
20.
Intrauterine fetal growth restriction (IUGR), the main cause of premature delivery and fetal mortality, has been suggested to involve oxidative stress. We found elevated values of indices of oxidative stress in the blood serum of pregnant women with IUGR: increased levels of malondialdehyde and 4-hydroxyalkenals, decreased activity of α-1-antitrypsin and decreased total antioxidant capacity of the serum, with respect to healthy pregnancy. Twenty day treatment with 3 g of l-arginine and 75 mg of acetylsalicylic acid daily resulted in a decrease of the level of lipid peroxidation products and augmentation of α-1-antitrypsin activity. This study confirms the occurrence of oxidative stress in IUGR and demonstrates the beneficial effect of arginine/acetylsalicylic acid therapy in reducing oxidative stress in IUGR.  相似文献   
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