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101.
本文对有自然流产史的妇女及其配偶进行了 HLA—Ⅰ类抗原测定。其中流产仅1~2次者47对,流产3次或以上(习惯性流产)者42对.并以40对正常生育的夫妇作比较.结果显示有流产史的夫妇间存在 HLA 相容性增加的趋向。流产组夫妇间共有2个或以上抗原者显著高于正常对照组。而夫妇间无一抗原相同者,则习流组显著低于对照组。与国外的许多报导一致。提示夫妇间的人类主要组织相容性抗原相容性增加,即双方共有2个或以上的 HLA 抗原,产生 HLA 抗原纯合子胎儿的机会增加,以致妊娠得不到足够的免疫防护,可能是导致自然流产的一个因素。 相似文献
102.
The literature on poisoning accidents or ingestion of toxicsubstances in children is reviewed. Special emphasis is givento the phenomenon of recurrent or repeat episodes. Recommendationsare made concerning means for identifying children who are atrisk for repeat poison episodes, as well as for developing methodsof intervention to prevent such occurrences. 相似文献
103.
Endothelial nitric oxide synthase gene polymorphism in women with idiopathic recurrent miscarriage 总被引:7,自引:0,他引:7
Tempfer C Unfried G Zeillinger R Hefler L Nagele F Huber JC 《Human reproduction (Oxford, England)》2001,16(8):1644-1647
BACKGROUND: Lack of endothelium-derived nitric oxide is associated with vasospasm and vascular infarction. We investigated the relationship between idiopathic recurrent miscarriage and a polymorphism of the gene encoding endothelial nitric oxide synthase (NOS3). METHOD: In a prospective case-control study, 105 women with idiopathic recurrent miscarriage and 91 healthy controls were investigated. We used the polymerase chain reaction to identify the different alleles of a 27 base pair tandem repeat polymorphism in intron 4 of the NOS3 gene. RESULTS: The wild type B allele was identified on 329 out of 392 chromosomes (frequency 0.84). The polymorphic A allele was present on 63 chromosomes (frequency 0.16). The genotype frequencies were as follows: 68% (B/B), 31% (A/B) and.5% (A/A). The distribution of genotype frequencies was significantly different between the study and control groups for allele A/B heterozygotes (NOS3(A/B)) (36.7 versus 23.8%, P = 0.03, OR 1.6, 95% CI 1.1--3.8). Only one individual was homozygous for the A allele (NOS3(A/A)). She was in the study group. Between women with primary and secondary recurrent miscarriages, no statistically significant difference between the distribution of NOS3(A/B) genotypes (28 versus 34%) was observed. CONCLUSIONS: These data support a role for the NOS3 gene as a genetic determinant of the risk of idiopathic recurrent miscarriage. 相似文献
104.
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
105.
The emerging role of immunoregulation of fibrinogen-related procoagulant Fgl2 in the success or spontaneous abortion of early pregnancy in mice and humans. 总被引:12,自引:0,他引:12
D A Clark J W Ding G Chaouat C B Coulam C August G A Levy 《American journal of reproductive immunology (New York, N.Y. : 1989)》1999,42(1):37-43
PROBLEM: Abortion of chromosomally normal embryos in the CBA X DBA/2 mating combination is triggered by release of Th1 cytokines (tumor necrosis factor [TNF]-alpha, interferon [IFN]-gamma, and interleukin [IL]-1), which cause abortion via a novel prothrombinase, Fgl2, and polymorphonuclear leukocytes. The site of activation may be maternal vascular endothelium on arteries and veins nourishing the placenta. Activation of coagulation is also prominent in spontaneous abortion of chromosomally normal human embryos. We asked where is Fgl2 up-regulated in the uterus in murine abortions, and if similar Fgl2 expression occurs in human pregnancy failure. METHODS: Control CBA X DBA/2 pregnant mice, or from mice injected with TNF-alpha + IFN-gamma on day 7.5 of gestation, were removed on day 8.5, fixed, sectioned, and subject to in situ hybridization for Fgl2. Sections were also stained for fibrin. Elective first trimester termination samples or biopsies taken early in the course of a recurrent miscarriage were similarly fixed, sectioned, and analyzed by in situ hybridization. Control and cytokine-treated mice were anticoagulated with heparin, an activator of antithrombin III, and/or the direct anti-thrombin inhibitor hirudin. RESULTS: Low level Fgl2 expression localized to basal decidua remote from the embryo was noted in control mice; cytokine treatment, which causes greater than 80% of abortions, produced a striking up-regulation in this area as well as in a band at the junction of decidua and myometrium. Trophoblast also became strikingly positive. Fgl2 expression was associated with increased fibrin staining. Anticoagulation significantly protected against abortions, but doses were limited by the complication of retroplacental hemorrhage. In tissue from normal first trimester pregnancy, minimal Fgl2 positivity was seen in some villous syncytiotrophoblast, in villous stroma, cytotrophoblast, and in some cells in decidua. In spontaneous abortion of normal embryo, striking Fgl2 positivity was seen in syncytiotrophoblast and extravillous cytotrophoblast, in association with areas of thrombus formation. CONCLUSIONS: Fgl2 appears to be physiologically expressed and may protect against the internal danger of maternal and/or fetal bleeding during pregnancy and at parturition; a role in inhibiting transplacental traffic is also possible. External dangers in the form of stress, endotoxin, and antigens eliciting Th1 cytokine responses upregulate Fgl2 prothrombinase in trophoblast as well as in decidua, which results in spontaneous abortion of immunogenetically "weaker" embryos. 相似文献
106.
LH-RH in picomole concentrations evokes excitation and inhibition of rat arcuate neurones in vitro 总被引:3,自引:0,他引:3
A medial sagittal brain slice was developed, which enabled electrophysiological recording from spontaneously active neurones adjacent to the infundibular recess of the rat arcuate nucleus. Luteinizing hormone-releasing hormone (LH-RH) (10 nM-10 pM) significantly altered the frequency of 21 out of 31 units tested, exciting 14 and inhibiting 7 others. The excitatory responses were often not maintained during the exposure to LH-RH but either returned to pre-exposure frequency or displayed an inhibition of discharge. A neural model incorporating recurrent inhibition of LH-RH-excited neurones is proposed to explain these responses, thought to be endogenously evoked by collateral innervation of the arcuate nucleus by medial preoptic neurones projecting to the median eminence. 相似文献
107.
Rai R Tuddenham E Backos M Jivraj S El'Gaddal S Choy S Cork B Regan L 《Human reproduction (Oxford, England)》2003,18(12):2540-2543
BACKGROUND: Some cases of recurrent miscarriage have a thrombotic basis. Thromboelastography is a rapid, reproducible test of whole-blood haemostasis. METHODS: Thromboelastography was performed in 494 consecutive, non-pregnant women (median age 35 years; range 21-48) with a history of miscarriages at <12 weeks gestation (median 4; range 3-12) and 55 parous women (median age 33 years; range 20-41) with no history of pregnancy loss. The prospective outcome of untreated pregnancies amongst 108 women with recurrent miscarriage was studied. RESULTS: The maximum clot amplitude (MA) (median 66.0 mm; range 48.0-76.0) was significantly higher and the rate of clot lysis (LY30) (median 2.5%; range 0.5-7.8) significantly lower amongst women with recurrent miscarriage compared with controls (MA 61.5 mm; range 50.0-67.0; P = 0.01; LY30 4.9%; range 2.9-9.7; P = 0.01). The pre-pregnancy MA was significantly higher amongst women who subsequently miscarried (median 66.0 mm; range 54.0-73.0) compared with those whose had a live birth (median 61.7 mm; 48.0-71.5; P < 0.01). A pre-pregnancy MA >or=64 mm has a sensitivity of 68% and specificity of 82% to predict miscarriage. CONCLUSIONS: Thromboelastography identifies a subgroup of women with recurrent miscarriage to be in a prothrombotic state outside of pregnancy. Women in such a state are at increased risk of miscarriage in future untreated pregnancies. 相似文献
108.
目的:探讨不孕及反复自然流产与抗精子抗体(AsAb)的关系。方法:用金标法检测有反复自然流产史患者245例(流产组)、原发或继发不孕患者164例(不孕组)及正常妇女40例(对照组)血清中的AsAb。结果:不孕组AsAb总阳性率52.44%,流产组总阳性率48.57%,与对照组比较差异均有统计学意义(P〈0.05)。结论:AsAb与不孕及反复自然流产有着密切关系。 相似文献
109.
Satoru Honma Akinari Tokiyoshi Katsushi Kawai Masahiro Koizumi Kodo Kodama 《Anatomical science international / Japanese Association of Anatomists》2008,83(4):232-238
A radial artery running beneath the biceps tendon was found in the cadaver of a Japanese woman during a student dissection
course at Kumamoto University School of Medicine in 2006. The brachial artery bifurcated into the radial artery and the ulnar
artery in the cubital fossa, and the radial artery twisted laterally running beneath the biceps tendon, and when it was situated
laterally to the tendon, twisted distally at the level of the radial tuberosity, and then twisted medially again. After the
radial artery passed over the biceps tendon, it turned distally and continued as a normal radial artery. The superficial brachial
artery, which coexisted with the brachial artery, was given off from the axillary artery and it continued to the final twist
of the radial artery. The course of this radial artery is similar to the arterial rings surrounding the biceps tendon, found
during the same dissection course. The arterial rings were formed between the brachial artery and the radial artery, and their
proximal origins ran beneath the biceps tendon, while the distal origins were superficial. The present arterial variation
is thought to have occurred when the normal part of the radial artery in the cubital fossa was substituted by the arterial
ring, coexisting with the superficial brachial artery, which usually disappears during normal development. Furthermore, it
is suggested that a part of the arterial ring always remains as a radial recurrent artery. 相似文献
110.