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61.
D. Cremaschi C. Rossetti M. T. Draghetti C. Manzoni V. Aliverti 《Pflügers Archiv : European journal of physiology》1991,419(5):425-432
Transepithelial pathways of macromolecule transport have been studied in vitro in rabbit nasal respiratory mucosa, maintained at 27° C. Transepithelial electrical potential difference, short-circuit current and resistance were 3.4±0.5mV (submucosa positive), 65.0±6.7 A cm–2 and 52.1±5.6 cm–2 respectively (n=15). These electrical characteristics are those of a leaky epithelium allowing macromolecules to permeate paracellularly. A detailed permeation study of a polypeptide (elcatonin, M
w=3362) was also undertaken. Elcatonin mucosa-submucosa (J
ms) and submucosa-mucosa (J
sm) fluxes were measured by radioimmunoassay. With 10 g/ml elcatonin, J
ms was significantly larger than J
sm for the whole 120-min period of observation; net flux showed a maximum in the first 30 min (J
ms=13.6±1.0 ng cm–2 h–1, J
sm=1.4±0.1 ng cm–2 h–1, n=10). J
ms fell towards the value of J
sm if the temperature was reduced to 4°C or if the mucosa was simultaneously treated with 0.1 mM dinitrophenol and 3 mM monoiodoacetate. J
ms and J
net followed saturation kinetics with increasing elcatonin concentrations. Adrenocorticotropic hormone (M
r=4500) produced a similar pattern to elcatonin. However, J
ms and J
sm were not significantly different from each other at any time either for [3H]sucrose (M
w=342) or for [14C]polyethyleneglycol-4000 (M
w=4000) when present in the bathing medium at 500 M concentration. The results show active transport of polypeptides in parallel with passive permeation (possibly through leaky intercellular junctions). Active transport does not appear to be related to nonspecific pinocytosis but to receptor-mediated endocytosis. The latter may be important for the sampling of potential antigens from the nasal lumen. 相似文献
62.
63.
不同剂量HCG对体外受精-胚胎移植的影响 总被引:2,自引:0,他引:2
目的 :比较使用不同剂量人绒毛膜促性腺激素 (HCG)对体外受精 /胞浆内单精子注射 (IVF/ICSI)的结局及对卵巢过度刺激综合征 (OHSS)发病率的影响。方法 :对在本所接受IVF/ICSI辅助生育的 2 6 2例采用GnRH a长方案促排卵的患者进行回顾性分析 ,按HCG用量分为A组 (HCG 5 0 0 0~ 6 0 0 0U)、B组 (HCG 80 0 0~ 10 0 0 0U)。结果 :两组临床妊娠率分别为 35 .94 %和 38.0 5 % (P >0 .0 5 ) ,OHSS发生率分别为 2 .34%和 4 .4 8% (P >0 .0 5 )。结论 :减少HCG用量后对IVF/ICSI的临床妊娠率无明显影响 ,且可以减少OHSS的发生。 相似文献
64.
A. Greenough B. Yuksel S. Naik P. Cheeseman K. H. Nicolaides 《European journal of pediatrics》1997,156(7):550-552
Neonatal respiratory difficulties are increased following second trimester amniocentesis. In preterm, prolonged rupture of
the membranes, respiratory outcome is particularly poor when rupture occurs in the first trimester. It therefore seems likely
that first trimester/early amniocentesis (EA) would be associated with severe respiratory problems necessitating a high neonatal
intensive care unit (NICU) admission rate. To test that hypothesis, the requirement for admission to the NICU of 278 infants
whose mothers had undergone EA, 262 whose mothers had undergone chorion villus sampling (CVS group) and 264 controls whose
mothers had undergone no invasive procedures were reviewed as were their diagnoses if they needed admission. There was no
significant difference in the mode of delivery, gestational age or gender distribution of the three groups and the median
maternal age of the EA and CVS groups was similar. Nineteen EA, eight CVS and five control infants required admission to the
NICU (EA versus controls, P < 0.01; EA versus CVS plus controls, P < 0.005). Nine EA, one CVS and four control infants had suffered respiratory problems
(EA versus CVS P < 0.05). Logistic regression analysis demonstrated that immaturity and EA were significantly associated with
a requirement for NICU admission. We conclude infants whose mothers have undergone EA may be at increased risk for NICU admission,
this is partly due to respiratory problems but the association is uncommon.
Received: 1 August 1996 / Accepted: 12 December 1996 相似文献
65.
James D. Goldberg MD Monica M. Wohlferd MS 《American journal of obstetrics and gynecology》1997,176(6):1349-1353
OBJECTIVE: Chromosomal mosaicism has been reported in about 1% to 3% of chorionic villus sampling specimens. This report provides incidence and outcome information that should be useful in counseling patients found to have mosaicism on chorionic villus sampling.STUDY DESIGN: A retrospective analysis of 11,200 consecutive patients undergoing chorionic villus sampling at the University of California, San Francisco, during the period from Jan. 1, 1984, to June 1, 1996, was undertaken.RESULTS: A total of 140 cases of mosaicism were identified for an incidence of 1.3%. Follow-up information was available for 130 cases, 26 of which (20%) were confirmed in fetal tissue. Confirmation rates for specific types of mosaicism were as follows: autosomal trisomy 7.6%, sex chromosome 25%, structural abnormality 27.3%, and marker chromosome 77.8%. Neonatal outcome was normal in all cases for which pregnancy continued.CONCLUSION: The data indicate that in most cases of chromosomal mosaicism found by chorionic villus sampling the mosaicism is unlikely to be clinically significant in the fetus. (Am J Obstet Gynecol 1997;176:1349-53.) 相似文献
66.
甲胎蛋白、游离雌三醇及绒毛膜促性腺激素测定在产前诊断唐氏综合征中的应用 总被引:1,自引:0,他引:1
目的:探讨胎儿胎盘产物甲胎蛋白(AFP)、游离雌三醇(uE3)和β绒毛膜促性腺激素(β-hCG)水平与胎儿唐氏综合征发病的关系。方法:用放射免疫法测定17例妊娠唐氏综合征胎儿的孕妇(病例组)和131例妊娠正常胎儿孕妇(对照组)的外周血、羊水及脐血中AFP、uE3和β-hCG水平。结果:病例组孕妇外周血、羊水和脐血中AFP水平均低于对照组(P<0.05);uE3水平也均低于对照组(P<0.05);β-hCG水平均高于对照组(P<0.05)。结论:检测孕妇外周血中AFP、uE3、β-hCG可用于胎儿唐氏综合征的产前诊断 相似文献
67.
68.
Suzanne M. Jacques Faisal Qureshi Barbara J. Doss Adnan Munkarah 《Pediatric and developmental pathology》1998,1(5):380-387
Choriocarcinoma arising in the placenta, or intraplacental choriocarcinoma, has seldom been reported, particularly in the
absence of maternal metastases. Reluctance to diagnose choriocarcinoma in the presence of chorionic villi can delay diagnosis;
however, timely diagnosis of choriocarcinoma is prognostically important, both for the mother and infant. We report the clinicopathologic
findings in five mothers and infants in whom choriocarcinoma was identified in the placenta. None of the mothers had a history
of gestational trophoblastic disease in previous pregnancies. Three placentas were similar with a single small lesion grossly
suggesting a small infarct; microscopically these consisted of infarcted areas surrounded by choriocarcinoma. These three
mothers were unusual in that none had metastatic choriocarcinoma; two were treated with chemotherapy and remained disease-free;
the third was lost to follow-up shortly following delivery. The remaining two mothers had known pulmonary metastases at time
of delivery. One of these latter two placentas contained a large marginal lesion microscopically identified as choriocarcinoma.
The fifth placenta had rare microscopic foci of choriocarcinoma, and sheets of necrotic choriocarcinoma were identified in
“blood clot” submitted with the placenta. In four of the five cases the choriocarcinoma appeared to be arising from otherwise
normal chorionic villi, and in no case was there invasion of the villous stroma. All of the infants survived, and none had
evidence of choriocarcinoma. These cases support the concept that choriocarcinoma associated with otherwise normal pregnancy
arises in the placenta and may be more common than reported.
Received August 11, 1997; accepted December 8, 1997. 相似文献
69.
嗓音频谱分析中/a/,/i/音采样的比较 总被引:8,自引:1,他引:8
应用486微型计算机和北京邮电大学通用信号谱分析系统分别对30例青年女性喉病患者和36例健康对照组的/a/、/i/音嗓音信号进行频谱分析,比较其相对信噪比,结论是在频谱分析中用/a/音采样较/i/音更易检出病态嗓音. 相似文献
70.
Bulent Urman Cengiz Alatas Senai Aksoy Alp Nuhoglu Aycan Sertac Basak Balaban 《Journal of assisted reproduction and genetics》1998,15(3):125-128
Purpose:
Our purpose was to determine the feasibility and efficacy of performing testicular or epididymal sperm retrieval prior to the injection of human chorionic gonadotropin (hCG).
Methods:
This report deals with 87 sperm-positive percutaneous epididymal sperm aspiration (PESA), percutaneous testicular sperm aspiration (PTSA), or testicular sperm extraction (TESE) cycles. All sperm retrieval procedures were performed prior to administration of hCG to the women. Retrieved spermatozoa were cultured in vitro in simple medium for approximately 40 hr prior to intracyto-plasmic sperm injection.
Results:
In all but one cycle in which TESE was performed for nonobstructive azoospermia, motile sperm were available for ICSI. The overall fertilization rate was 53%. Pregnancy rate per transfer and implantation rate per embryo were 41.2 and 15.7%, respectively.
Conclusions:
Satisfactory fertilization and pregnancy rates can be achieved when PESA, PTSA, or TESE is performed prior to the injection of hCG followed by in vitro culture of spermatozoa approximately 40 hr before ICSI. Scheduling of testicular or epididymal sperm retrieval cases in this way appears to ease the workload on laboratory and operating room personnel. Furthermore, withholding hCG when sperm is absent may obviate the unnecessary risk of ovarian hyperstimulation when spermatozoa cannot be retrieved. 相似文献