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In-vitro maturation of human oocytes is an important technique in assisted reproduction due to its potential for reducing the use of fertility drugs. We offered this technique as an alternative to cancelling the cycle to a patient who was at risk of ovarian hyperstimulation syndrome (OHSS) after treatment with gonadotrophin- releasing hormone analogue (GnRHa) and human menopausal gonadotrophin (HMG). The patient had 40 visible antral follicles with a maximum diameter of 13 mm and an oestradiol concentration of 14,000 pmol/l on cycle day 12. Immature oocytes were aspirated transvaginally under ultrasound guidance. Ten cumulus-enclosed oocytes were harvested and nine of them completed nuclear maturation to metaphase II after 48 h in culture. By 18 h after an intracytoplasmic sperm injection (ICSI) procedure, seven of these metaphase II stage oocytes displayed two distinct pronuclei and two polar bodies. All fertilized oocytes but one underwent cleaveage; four of these were transferred 2 days later. Endometrial priming was initiated with 8 mg oestradiol valerate daily from the day of oocyte retrieval and 50 mg progesterone was injected i.m. daily starting 2 days after that. A single intrauterine sac was seen containing one fetus with positive fetal heart beat on ultrasound at 7 weeks of gestation. Unfortunately, the pregnancy ended at 24 weeks shortly after premature rupture of membranes; a live healthy-looking girl was delivered who died 18 days later.   相似文献   
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按Bishop方法,在小鼠血液里诱导生成大量网织红细胞,然后提取网织红细胞。用激光衍射法测得小变形指数(DI)d和变形恢复过程(即松驰过程)中细胞变形恢复到最大值(DI)max半的时间t0.5(变形恢复半时间),将测得结果分别代入细胞膜的膜剪切弹性模量(E)公式和表面粘度(μm)公式,计算出网织红细胞和成熟红细胞膜的膜剪切弹性模量(E)和表面粘度(μm),并用荧光偏振法测量它们的膜流动性。发现网织红细胞与成熟红细胞的膜的剪切弹性模量(E)和表面粘度(μm)及膜的流动性有着明显的不同。这对研究由于贫血等原因造成的网织红细胞增多情况下,全血的微观流变特性有着重要的临床意义,对我们认识哺乳类网织红细胞的微观流变特性有重要理论意义及认识哺乳类动物网织红细胞向成熟红细胞转变的微观流变特性变化有着重要理论意义。  相似文献   
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Cryopreservation of single human spermatozoa   总被引:6,自引:5,他引:6  
A procedure is described that allows cryopreservation and efficient post-thaw recovery of either a single or a small group of human spermatozoa. This is achieved by injecting them into cell-free human, mouse or hamster zonae pellucidae before the addition of cryoprotectant. The method involves a combination of physical micromanipulation procedures and glycerol-mediated cryoprotection. Zonae were tracked by positioning them in straws between two small air bubbles prior to freezing. Spermatozoa from poor specimens were cryopreserved and their fertilizing ability after thawing was compared with that of fresh spermatozoa from fertile men. Human eggs used for fertilization testing were either 1 day old or in-vitro matured. Only 2% of the frozen zonae were lost and >75% of spermatozoa cryopreserved in this manner were recovered and prepared for intracytoplasmic sperm injection. The feasibility of cryopreserving a single spermatozoon was assessed. Fifteen motile spermatozoa were frozen in 15 zonae, of which 14 were recovered after thawing. Ten were injected into spare eggs, of which eight became fertilized. Spermatozoa recovered mechanically from human zonae fertilized the same proportion of oocytes as fresh fertile control spermatozoa. The recovery and fertilization rates with spermatozoa frozen in animal zonae were 87 and 78% respectively. The fertilization rate was marginally higher (P < 0.05) than that for spermatozoa frozen in human zonae, perhaps because the latter may have acrosome reacted more frequently. The zona pellucida appears to be an ideally suited sterile vehicle for storage of single spermatozoa.   相似文献   
578.
Both anti-single-stranded (ss) and anti-double-stranded (ds) DNA antibodies are associated with the autoimmune disease systemic lupus erythematosus (SLE), but only anti-dsDNA antibodies are considered one of the diagnostic criteria. Using Ig transgenes coding for anti-DNA we have determined the fate of anti-dsDNA B cells in a non-autoimmune environment. In a Rag-2 wild-type background, B cells expressing the anti-dsDNA Ig transgenes are present in the spleen but dsDNA specificity is disrupted due to expression of endogenous L chains. In a Rag-2-deficient background where co-expression of endogenous Ig is blocked, splenic B cells expressing only the anti-dsDNA transgene Ig are present, indicating that endogenous Ig expression is not required for bone marrow export. The anti-dsDNA B cells that persist are profoundly crippled in that they are unable to proliferate to lipopolysaccharide or anti-Ig stimulation. Furthermore, these anti- dsDNA Ig transgene B cells show a decreased lifespan relative to non- transgene BALB/c B cells. Persistence of anti-dsDNA B cells in the periphery of non-autoimmune mice raises the possibility that their appearance in the context of SLE is due to their reactivation by T cell help.   相似文献   
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Limited information is available about the sonomorphological changes in metastatic neck nodes during radiotherapy. The aim of this study was to evaluate the pattern of sonomorphological changes in metastatic neck nodes with radiotherapy. The study population consisted of 16 consecutive patients planned for radical radiotherapy to the head and neck. All patients were subjected to four ultrasound examinations: before therapy, at 46 Gy, at the conclusion of radiation and at first follow up. A total of 59 ultrasound examinations were performed on 16 patients. The difference between the mean number of nodes detected per patient before (10.6) and after (7.8) radiation was significant (P = 0.05). Sixteen nodes were categorized as malignant at first sonography, half of which reverted back to normal by the end of radiation. Changes in the sonomorphology of malignant cervical lymph nodes occur with radiotherapy with more that half demonstrating reversion to normal pattern. Future studies correlating this with histopathology should be considered.  相似文献   
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