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91.
The Donation of Oocytes to Known Recipients   总被引:2,自引:0,他引:2  
The supply of donated oocytes from an in vitro fertilization programme has always been inadequate, especially following the successful cryopreservation of human embryos. There have been no previous reports of women donating their oocytes to known recipients. All of 7 women who donated all their oocytes to known recipients responded to a posted questionnaire. No differences in social characteristics between this group and another group of infertile women treated on an in vitro fertilization programme, who donated some of their excess oocytes anonymously were noted, except that the known donor group had a relatively high average parity, i.e. 3. No differences in attitudes towards donating oocytes were noted between these groups except that the known donor group felt a significantly greater connection towards the potential child.  相似文献   
92.
The addition of polysialic acid (PSA) to neural cell adhesion molecule (NCAM) facilitates axon growth. Here we use Western blots and immunohistochemistry to examine expression of PSA-NCAM during optic nerve regeneration. In lizard, retinal ganglion cell axons become transiently PSA-NCAM positive. By contrast, goldfish RGC axons are PSA-NCAM negative both in normal animals and throughout regeneration with the exception of a PSA-NCAM-positive fascicle arising from newly generated RGCs. Transient sialylation of NCAM in lizard may assist regeneration in the nonpermissive reptilian visual pathway and facilitate the reestablishment of a crude topographic map; down-regulation in the long term may contribute to the breakdown in topography. The lack of sialylation in goldfish presumably reflects the permissive nature of the substrate allowing axon regeneration and the successful reestablishment of a topographic map.  相似文献   
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To estimate the incidence and causes of secondary thrombocytosis in children, a 12 month study of all patients attending a children's hospital and discovered to have a platelet count over two times the upper normal limit (> 800 x 10(9)/l) was undertaken. Data so obtained were analysed both separately and together with those from two previous studies to gain as broad a perspective as possible. Of 7916 children who had platelet counts during the study period, 36 (0.5%) produced a value > 800 x 10(9)/l; there were 19 boys and 17 girls. There was a preponderance of young infants (median age 13 months). Twenty seven of the 36 had some sort of associated infection, bacterial in 18 and viral in nine. The other nine were either recovering from anti-neoplastic chemotherapy (n = 6), were post-operative (n = 2), or simply iron deficient (n = 1). Combining these patients with those described in previous studies allowed a review of 139 unselected children with very high platelet counts. Fifty three (38%) had infections, 29 (20%) had traumatic or surgical tissue damage, 16 (11%) had malignant disease undergoing chemotherapy or surgery, and 13 (9%) had connective tissue or autoimmune disorders. Secondary thrombocytosis is not rare and is most frequently seen in very young infants after infection. It can arise in a wide variety of other circumstances including rebound from myelosuppression, iron lack, or as part of an acute phase response. It is clinically unimportant in terms of morbidity and requires no treatment other than that for the primary condition.  相似文献   
95.
Two children with acute lymphoblastic leukaemia (ALL) taking daily 6-mercaptopurine as part of a national UK therapeutic trial repeatedly developed profound myelosuppression on 25% of the standard protocol dose. Both were found to have undetectable intracellular activity of thiopurine methyltransferase (TPMT), an enzyme controlling one of the major alternative catabolic pathways of 6-mercaptopurine, and both produced higher concentrations of cytotoxic drug metabolites at 10-25% of the protocol dose than other patients taking 100%. It is supposed that these patients represent the 0.33% of the normal population constitutionally lacking TPMT. It is important to recognise such individuals both to avoid fatal bone marrow failure through inadvertent overdosage, and to be reassured that an adequate drug effect can be achieved at around 10% of the standard dose.  相似文献   
96.
Multiple myeloma: evaluation by CT   总被引:3,自引:0,他引:3  
Schreiman  JS; McLeod  RA; Kyle  RA; Beabout  JW 《Radiology》1985,154(2):483-486
Although patients who have multiple myeloma usually have straightforward clinical symptoms and corroborative radiographs, in some instances, these patients will present atypically, with symptoms suggesting active disease but radiographs that are normal or nonspecific. We reviewed the records of 32 patients who had documented multiple myeloma and had undergone CT examinations, assessing the value of those examinations. Although CT is not indicated in all patients who have multiple myeloma, it is especially useful in patients who have bone pain and normal or nonspecific radiographs. CT provided confirmatory information in all cases in which lesions were seen on radiographs. CT also frequently demonstrated a greater extent of disease than could be appreciated on the radiographs.  相似文献   
97.
The difficulties encountered in producing highly specific antisera to human chorionic gonadotrophin (hCG) were overcome by the use of hybridoma technology. A panel of monoclonal antibodies directed toward hCG and its subunits was produced. Of the four antibodies which were fully characterized, one recognized the intact hCG molecule only, a second recognized only the free beta-subunit, a third recognized only the free alpha-subunit and the fourth bound to the beta-subunit of hCG both when it was in the free form and when it was associated with the alpha-subunit forming the intact hCG molecule. There was no significant cross-reaction of any of these antibodies with the pituitary glycoprotein hormones. The four antibodies had high binding affinities which should permit their use in immunoassays for measurement of circulating levels of hCG and its subunits.  相似文献   
98.
Sleep-disordered breathing and oxygen desaturation in obese patients   总被引:3,自引:0,他引:3  
Fourteen morbidly obese subjects, referred to our institution for bypass surgery for obesity, were studied with regard to pulmonary function and respiratory patterns during sleep. The seven female patients experienced no episodes of desaturation or disordered breathing during sleep. Six of the seven male patients experienced desaturation or disordered breathing. The one who did not had hypogonadism, suggesting that testosterone may have a role in the regulation of breathing during sleep. The two patients with the most frequent episodes of apnea and lowest oxygen saturation had a clinical picture consistent with the pickwickian syndrome. This supports the relationship previously noted between the degree of hypoxia and the presence of hypersomnolence.  相似文献   
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