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31.
A. N. Valuiskikh Yu. A. Romashkova A. V. Danilkovich K. G. Freze G. T. Sukhikh E. V. Makarov 《Bulletin of experimental biology and medicine》1997,123(3):276-278
Similar to chorionic gonadotropin, synthetic fragment of the β-subunit of chorionic gonadotropin (128th–145th amino acid),
inhibits mitogen-stimulated proliferation of human lymphocytesin vitro and binds to membrane receptors of human peripheral blood monocytes.
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 123, No. 3, pp. 319–322, March, 1997 相似文献
32.
J. A. J. M. van den Hurk P. M. van Zandvoort F. Brunsmann I. H. Pawlowitzki W. Holzgreve P. Szabo F. P. M. Cremers B. A. van Oost 《American journal of medical genetics. Part A》1992,44(6):822-823
We performed prenatal testing to predict the inheritance of choroideremia (CHM) using a linked polymorphic DNA marker, DXS95. DNA analysis of chorionic villi at the 12th week of pregnancy indicated that the allele at risk had not been passed from the heterozygous mother to the fetus. This prenatal exclusion of choroideremia was confirmed by polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP) analysis. © 1992 Wiley-Liss, Inc. 相似文献
33.
Sensitization and exposure to house-dust-mite allergens is an important cause of asthma. Standardized, reliable, and reproducible methods for measuring exposure are essential for the assessment of the relationship between exposure, sensitization, and asthma. This study investigated the variability of the house-dust-mite allergen Der p 1 concentration in reservoir dust collected within whole carpets in living rooms and bedrooms. The carpets of nine bedrooms and 11 living rooms were sampled. Each room was divided into 1 m2 areas measured from wall to wall where the carpet was accessible. Reservoir dust samples were collected by vacuuming each 1 m2 area for 2 min. Der p 1 was assayed by a two-site monoclonal-antibody-based immunometric ELISA. Der p 1 was detectable in the carpets of nine bedrooms and six of the 11 living rooms. Within these 15 rooms, there was a wide range of Der p 1 levels. The smallest range of allergen within single room was 0.9 μg Der p 1/g dust (0.2 and 1.1 ng/g; 5.5-fold difference), and the largest was 149.2 μg Der p 1/g dust (0.8 and 150 μg/g; 192-fold difference). The mean range of allergen levels in the living rooms was 11.5 jig Der p 1/g of dust, and the mean coefficient of variation of these rooms was 80.2%. illustrating the huge variation of mite allergen levels within each room. The variation within bedrooms was also large, with a mean coefficient of variation value of 88.7%. The coefficient of variation was significantly lower around soft furnishings or beds (57%) than in the rest the room (89.3%), with the mean difference being 32% (95% CI 27ndash;63%; P=0.04). In conclusion, this study has shown that there is a great variation of Der p 1 levels between areas within a room. No consistent pattern of distribution of mite allergen within a room was found. Der p 1 levels in areas around soft furnishings and beds varied less than the levels in the rest of room. 相似文献
34.
杭州地区8516例孕中期妇女产前筛查回顾性分析 总被引:2,自引:0,他引:2
目的分析杭州地区孕中期妇女运用甲胎蛋白(AFP)和游离绒毛膜促性腺激素β亚基(Free-βhCG)进行胎儿先天缺陷产前筛查的结果;并据此修正两筛查指标的孕周中位数值。方法对杭州地区孕14~20w的妇女进行产前AFP和Free-βhCG的检测。胎儿先天畸形由染色体核型分析、B超检查确诊,或经引产证实。应用非线性加权回归求得本地区两筛查指标的中位数,并计算中位倍数值进行分布拟合。比较标化前后检测效果。结果8516例受检孕妇,共筛查出唐氏综合征3例、爱德华综合征2例,神经管畸形7例,其他胎儿异常17例;杭州地区孕中期妇女AFP及Free-β-hcG中位数比欧洲妇女分别高18%和14%;用修正后的中位数重新分析,孕中期假阳性率降低。结论血清AFP、Free-βhcG联合检测,可作为杭州地区孕中期妇女产前筛查优选项目。而根据地域人群的差异,对Mu ltiCalc软件内嵌中位数进行修正后更适于杭州地区孕中期妇女的产前筛查。 相似文献
35.
36.
Choriocarcinoma has been described as the most frequent subtype of mediastinal germ cell tumors showing trophoblastic differentiation. We report a unique case of a placental site trophoblastic tumor, which developed in the mediastinum of a 14-year-old boy 2 years after the resection of a mature teratoma. The recurrent tumor was composed of a grossly hemorrhagic and necrotic mass. Histologically, diffusely infiltrating large polygonal cells with focal nodular growth and a teratomatous part containing mature intestinal, respiratory, and squamous epithelium with adjacent cutaneous adnexal structures were found. The typical morphologic features included vessel wall infiltration by the neoplastic cells with fibrinoid deposits and geographic necroses within the tumor masses. Characteristic diffuse positivity for melanoma cell adhesion molecule and human leucocyte antigen G was found on immunohistochemical investigation, confirming the diagnosis of placental site trophoblastic tumor. The patient died 1 year later after polychemotherapy. The outcome of this rare tumor is similar to the reported poor clinical outcome in patients with mediastinal choriocarcinomas. 相似文献
37.
Maternal serum beta-HCG and alpha-fetoprotein concentrations in singleton pregnancies following assisted reproduction 总被引:2,自引:0,他引:2
Perheentupa A Ruokonen A Tuomivaara L Ryynänen M Martikainen H 《Human reproduction (Oxford, England)》2002,17(3):794-797
BACKGROUND: The reason for the elevated levels of HCG in assisted reproduction pregnancies remains unknown. Our hypothesis was that this increase is caused by the ovarian superovulation therapy. METHODS: We compared the beta-HCG and alpha-fetoprotein (AFP) multiples of the median (MoM) in singleton pregnancies after IVF or ICSI with those achieved by frozen embryo transfer (FET) in spontaneous cycles. RESULTS: The HCG and AFP MoMs (plus minus SEMs) of 59 FET pregnancies were compared with 144 IVF (including 48 ICSI) pregnancies. The maternal HCG of pregnancies following ovarian stimulation was 1.31 plus minus 0.08 MoM compared with 1.35 plus minus 0.12 MoM in the unstimulated ones. The values for AFP were 1.06 plus minus 0.05 versus 1.11 plus minus 0.05 respectively. No significant differences could be observed between pregnancies following stimulated IVF/ICSI and unstimulated FET cycles. CONCLUSIONS: Our results show that second trimester maternal serum HCG is also elevated in singleton pregnancies following spontaneous FET cycles. The increased maternal serum HCG in IVF pregnancies is thus not related to superovulation therapy. Because of the elevated maternal serum HCG levels, serum screening cannot be performed reliably in pregnancies following assisted reproduction technology. Ultrasonographic detection of the nuchal translucency is unaffected and should be used for this group of women undergoing assisted reproduction. 相似文献
38.
39.
Gold RS Azem F Yovel I Wagman I Amit A Lessing JB 《Human reproduction (Oxford, England)》2000,15(6):1221-1224
This study was conducted to compare early serum human chorionic gonadotrophin (HCG) concentrations in singleton pregnancies achieved after intracytoplasmic sperm injection (ICSI), with those achieved after conventional in-vitro fertilization (IVF). Early serum HCG, 14-16 days after embryo transfer, was analysed in 99 IVF pregnancies achieved after ICSI (group A), and compared to 105 conventional IVF pregnancies (group B). All women were treated at the IVF Unit, Lis Maternity Hospital. Records were studied retrospectively. The mean +/- SE serum HCG concentration on day 14 after embryo transfer in group A was 190.5 +/- 17.4 mIU/ml, compared to 195.7 +/- 14.03 mIU/ml in group B. HCG concentration 14 days after embryo transfer in both groups A and B was higher in women with mechanical factor than in couples with male factor infertility or unexplained infertility (246 +/- 31.4, 183.3 +/- 16.4, 177.98 +/- 14.3 mIU/ml respectively). On the 16th day after embryo transfer, the HCG concentration increased, and the difference between the groups was maintained. Only in the subgroup of unexplained infertility did we find a difference in concentrations of HCG between ICSI and conventional IVF: on the 16th day following embryo transfer in this group there was a significant difference in HCG concentrations (395. 8 +/- 21 and 545.6 +/- 45.7 respectively; P = 0.04). HCG concentrations did not differ overall in the conventional IVF pregnancies compared with those achieved by ICSI. However, a statistical difference in early serum HCG concentrations was found in relation to the aetiology of infertility. 相似文献
40.
BACKGROUND: Exposure to fungi is often assessed by culturing floor dust or air samples. Our objective was to evaluate the relationships between dustborne and airborne fungi and to identify factors that modify these relationships. METHODS: From November 1994 to September 1996 sequential duplicate 45-l air samples were collected in bedrooms of 496 homes in the Boston area, using a Burkard culture plate sampler. After air sampling, bedroom floors were sampled with a vacuum cleaner that was modified to collect dust in a cellulose extraction thimble. Dust was sieved, and the fine dust was dilution-plated onto DG-18 media. RESULTS: Concentrations of total culturable fungi per gram of bedroom-floor dust were correlated weakly, but significantly, with those of indoor air (r = 0.13, P < 0.05). Concentrations of some individual taxa in the dust and indoor air were also weakly associated. Adjusting for the concentrations of fungi in outdoor air, dustborne fungal concentrations were positively associated with those in indoor air for the taxa Cladosporium and Penicillium, but not for total fungi. The indoor air fungal levels were often predicted by different covariates to those predicting fungal levels in dust. The type of housing (house or apartment) and the presence of carpeting were often predictive factors for dust fungi. In contrast, outdoor fungal levels were often predictive of the indoor air fungal levels. CONCLUSIONS: Because our data do not indicate a strong overall relationship between culturable fungi in dust and indoor air, the results from these two methods (dust and air sampling) likely represent different types of potential fungal exposures to residents. It may be essential to collect both air and dust samples, as well as information on housing characteristics, as indicators for fungal exposure. 相似文献