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11.
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Novero V; Camus M; Tournaye H; Smitz J; Verheyen G; Joris H; Derde MP; Van Steirteghem AC; Devroey P 《Human reproduction (Oxford, England)》1997,12(1):59-63
Serum follicle stimulating hormone (FSH) is routinely measured when
evaluating the infertile male for intracytoplasmic sperm injection (ICSI).
However, among the sperm parameters, only its relationship with sperm
concentration is well documented. Few investigations concern the
relationship between FSH and sperm motility and morphology, and the results
of ICSI. A retrospective study of 316 couples who underwent ICSI was
carried out to determine the relationships between serum FSH concentrations
in the male and (i) standard sperm parameters_(concentration, motility and
morphology) and (ii) fertilization, cleavage, pregnancy and implantation
rates after ICSI. There was an inverse correlation with sperm concentration
and total motility but no relationship was found with progressive motility
and sperm morphology. Neither was any relationship found between serum FSH
and fertilization, cleavage, pregnancy and implantation rates, and the
results of ICSI. These findings suggest the need to review the routine
measurement of serum FSH in the infertile male when ICSI is the planned
treatment procedure.
相似文献
13.
The metallothionein-null phenotype is associated with heightened sensitivity to lead toxicity and an inability to form inclusion bodies 总被引:2,自引:0,他引:2
Qu W Diwan BA Liu J Goyer RA Dawson T Horton JL Cherian MG Waalkes MP 《The American journal of pathology》2002,160(3):1047-1056
Susceptibility to lead toxicity in MT-null mice and cells, lacking the major forms of the metallothionein (MT) gene, was compared to wild-type (WT) mice or cells. Male MT-null and WT mice received lead in the drinking water (0 to 4000 ppm) for 10 to 20 weeks. Lead did not alter body weight in any group. Unlike WT mice, lead-treated MT-null mice showed dose-related nephromegaly. In addition, after lead exposure renal function was significantly diminished in MT-null mice in comparison to WT mice. MT-null mice accumulated less renal lead than WT mice and did not form lead inclusion bodies, which were present in the kidneys of WT mice. In gene array analysis, renal glutathione S-transferases were up-regulated after lead in MT-null mice only. In vitro studies on fibroblast cell lines derived from MT-null and WT mice showed that MT-null cells were much more sensitive to lead cytotoxicity. MT-null cells accumulated less lead and formed no inclusion bodies. The MT-null phenotype seems to preclude lead-induced inclusion body formation and increases lead toxicity at the organ and cellular level despite reducing lead accumulation. This study reveals important roles for MT in chronic lead toxicity, lead accumulation, and inclusion body formation. 相似文献
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Recessively inherited L-DOPA-responsive parkinsonism in infancy caused by a point mutation (L205P) in the tyrosine hydroxylase gene 总被引:4,自引:0,他引:4
18.
阮强 《中华微生物学和免疫学杂志》1994,(5)
研究资料表明,人巨细胞病毒(HCMv)单一蛋白的单一抗原决定簇只能被部分患者阳性血清识别。组建在血清学诊断中能够替代全病毒抗原的基因工程抗原,需要含有病毒多种主要抗原蛋白的抗原决定簇。为搞清在表达载体中重复插入某一抗原决定簇基因是否能表达出更高抗原效价的融会蛋白,我们用点突变的方法,在表达载体中分别插入了人HCMv的ppUL32蛋白羧基端一个抗原决定簇基因的1个、2个和3个拷贝。在免疫转印检测中,这些克隆表达的融合蛋白与特异性阳性血清的反应性差别不明显。这表明,插入表达载体中目的基因的多寡对表达蛋白的抗原效价没有显著影响。 相似文献
19.
Bhattacharya S; MacLennan F; Hamilton MP; Templeton A 《Human reproduction (Oxford, England)》1997,12(7):1440-1442
Although the conventional method of pain relief during outpatient oocyte
recovery involves physician-administered drugs, patient- controlled
analgesia (PCA) offers an alternative technique with the potential to give
women more control over peroperative analgesia. We conducted a prospective
randomized study to compare the effect of fentanyl administered either
through a PCA delivery system or by a physician. Thirty-nine women were
randomized to PCA during egg collection while 42 were allocated to receive
intermittent doses administered by a physician. Pain was evaluated by means
of a 100 mm linear analogue scale. The mean (SD) pain score in the PCA
group was 38.5 (19.8) while in the other group it was 46.1 (21.3) (P =
0.1). In the PCA group, 64% of women felt very satisfied with their
analgesia as compared with 57% in the non-PCA group (P = 0.6). Among the
PCA users, 39% of demands were successful. Significantly more fentanyl
(97.5 microg) was used in the PCA group than in the other group (84.6
microg) (P = 0.03). Though intraoperative PCA with fentanyl is an effective
alternative to physician-administered techniques, many women still feel the
need for more analgesia during the procedure.
相似文献
20.
Morphological studies have shown that macrophages and microglia undergo
apoptosis in the central nervous system (CNS) in acute experimental
autoimmune encephalomyelitis (EAE) in the Lewis rat. To assess the relative
levels of macrophage and microglial apoptosis, and the molecular mechanisms
involved in this process, we used three-colour flow cytometry to identify
CD45lowCD11b/c+ microglial cells and CD45highCD11b/c+ macrophages in the
inflammatory cells isolated from the spinal cords of Lewis rats 13 days
after immunization with myelin basic protein (MBP) and complete Freund's
adjuvant. Simultaneously, we analyzed the DNA content of these cell
populations to assess the proportions of cells undergoing apoptosis and in
different stages of the cell cycle or examined their expression of three
apoptosis- regulating proteins, i.e. Fas (CD95), Fas ligand (FasL) and
Bcl-2. Microglia were highly vulnerable to apoptosis and were
over-represented in the apoptotic population. Macrophages were less
susceptible to apoptosis than microglia and underwent mitosis more
frequently than microglia. The different susceptibilities of microglia and
macrophages to apoptosis did not appear to be due to variations in Fas,
FasL or Bcl- 2 expression, as the proportions of microglia and macrophages
expressing these proteins were similar, and were relatively high.
Furthermore, in contrast to T cell apoptosis, apoptosis of
microglia/macrophages did not occur more frequently in cells expressing Fas
or FasL, or less frequently in cells expressing Bcl-2. These results
indicate that the apoptosis of microglia and CNS macrophages in EAE is not
mediated through the Fas pathway, and that Bcl-2 expression does not
protect them from apoptosis. Expression of FasL by macrophages and
microglia may contribute to the pathogenesis and immunoregulation of EAE
through interactions with Fas+ oligodendrocytes and Fas+ T cells. The high
level of microglial apoptosis in EAE indicates that microglial apoptosis
may be an important homeostatic mechanism for controlling the number of
microglia in the CNS following microglial activation and proliferation.
相似文献