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571.
For her 40th birthday, Ann O'Hanlon of Saddlebrook gave herself and her family a present: a complete physical. But Mrs. O'Hanlon, who always had experienced heart palpitations, or as she puts it, "a racy heart," did not fare well. She did have an inkling something wasn't quite right. At home she was finding it increasingly difficult to raise her arms or lift her legs. But she had no idea how bad the situation was or was to become.  相似文献   
572.
To understand the cellular and biochemical nature of radioresistance in the strain M5 derived from Chinese hamster V79 cells, the sensitivity of the resistant cells towards CdCl2, Zn(Ac)2, and H2O2 by the colony forming ability has been tested. D0 values for these compounds in Chinese hamster V79 cells were 5.4 microM, 27.8 microM and 4.3 micrograms/ml respectively while for M5 cells these were 8.3 microM, 142.9 microM and 11.9 micrograms/ml respectively. The resistance to heavy metals as well as the oxidative damage could be reversed by the inhibition of glutathione synthesis by the drug buthionine sulfoximine (BSO). These set of data indicate that the cellular antioxidant glutathione plays an important role in the observed oxidant-resistant phenotype as well as heavy metal resistance in M5 cells.  相似文献   
573.
574.
This study investigated the forms of inhibin released into the circulation 1) in very early pregnancy, 2) after stimulation of the corpus luteum by exogenous hCG, and 3) in abnormal and failing human pregnancy. Samples were assayed by enzyme-linked immunosorbent assays for inhibin A, inhibin B, and inhibin pro-alphaC-related immunoreactivity (pro-alphaC-RI). The concentration of inhibin A rose steadily during the conception luteal phase to an initial peak 12 days after ovulation (104 +/- 23 pg/mL), then rose rapidly to a further peak 43 days after ovulation 424 +/- 6 pg/mL). The concentration of pro-alphaC-RI exhibited a much larger peak on day 15 after ovulation (1423 +/- 361 pg/mL), but fell thereafter. The concentration of inhibin B was low after ovulation and subsequently barely detectable in pregnancy. hCG treatment resulted in a significant rise in the concentrations of inhibin A and pro-alphaC-RI, but had no effect on the inhibin B concentration. The pro-alphaC-RI concentration was a better indicator of continuing pregnancy viability than either hCG or inhibin A. Early trophoblast secretes proportionately more bioactive inhibin than the corpus luteum. The corpus luteum and trophoblast do not secrete inhibin B into the circulation. These data support the concept of different physiological roles for different inhibin forms.  相似文献   
575.
576.
A patient is described, who was examined 1 year after surgery for mandibular cyst diagnosed as radicular near the !5 tooth and for plasty of the secondary osseous cavity with hydroxyapatite granulate. X-Ray examination revealed a cystic cavity near the roots of teeth !234. Histologic examination of tissue fragments and the remainder of hydroxyapatite granulate, obtained by cystectomy, helped diagnose a primordial cyst. Intensive bone regeneration was observed at the site of hydroxyapatite granule accumulation and fusion of the new bone with the granules to form a solid osseogranular complex. The authors recommend hydroxyapatite ceramic granules for surgical treatment of minor and medium bone defects and for corrective bone plasty.  相似文献   
577.
Recurrent spontaneous abortion is a frustrating problem for clinicians and their patients. Fortunately, a reasonable amount of research is being conducted to try and identify the causes of this disorder and develop appropriate and effective diagnostic tests and therapies. This review focuses on some of the factors that have been associated with recurrent abortion, such as cell-mediated immune responses to trophoblast antigens, the effect of oxidative stress, and the immunomodulatory properties of placental protein. The risk of recurrence is particularly high when the length of the embryo in early pregnancy is less than the 50th centile, even though cardiac activity may be present. Also, the risk is directly related to the number of previous abortions. Efficacy has been shown for treatment of unexplained recurrent abortion with allogeneic leukocyte immunization and possibly with intravenous immunoglobulin. Patients with oligomenorrhoea may benefit from treatment with human chorionic gonadotropin.  相似文献   
578.
Nijmegen breakage syndrome (NBS), a rare autosomal recessive condition also known as ataxia telangiectasia (AT) variants V1 and V2, is characterised by microcephaly, typical facies, short stature, immunodeficiency, and chromosomal instability. We report the clinical, immunological, chromosomal, and cell biological findings in 42 patients who are included in the NBS Registry in Nijmegen. The immunological, chromosomal, and cell biological findings resemble those in AT, but the clinical findings are quite different. NBS appears to be a separate entity not allelic with AT.  相似文献   
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