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排序方式: 共有774条查询结果,搜索用时 15 毫秒
771.
Fabry disease is a genetic disorder caused by the deficiency of α-galactosidase A, resulting in the lysosomal accumulation of glycosphingolipids. Fabry disease may result in cardiac, cerebral and renal complications. Cardiac abnormalities in patients with Fabry disease were first described in the 1960s. In the 1990s a form of Fabry disease confined to the heart was reported; however, this variant is extremely rare and a more appropriate concept is of cardiac predominance of the disease in some patients. Up to 60% of males with classic Fabry disease have cardiac abnormalities, including left ventricular hypertrophy, valvular dysfunction and conduction abnormalities. Recent data suggest that left ventricular mass and systolic function in patients with Fabry disease improve after 12 months of enzyme replacement therapy (ERT); however, many of the patients studied are relatively young and have mild cardiac abnormalities, suggesting that more research into the efficacy of ERT in older patients is necessary.
Conclusion: Cardiac manifestations are common in patients with Fabry disease and are not confined to a 'cardiac variant' of the disease. 相似文献
Conclusion: Cardiac manifestations are common in patients with Fabry disease and are not confined to a 'cardiac variant' of the disease. 相似文献
772.
It has long been known that seminal plasma contains factors that influence
the fertilizing capacity of spermatozoa in many different ways. However,
little is understood of the biochemical cascades triggered when spermatozoa
and seminal plasma interact. In this study, we examined how incubation with
seminal plasma affected protein tyrosine phosphorylation in human
spermatozoa. Increased protein tyrosine phosphorylation is a hallmark of
sperm capacitation in several mammalian species, including human. Seminal
plasma blocks protein tyrosine phosphorylation when added to washed,
non-capacitated spermatozoa. Removal of seminal plasma and incubation in
capacitating medium led to partial recovery of the tyrosine phosphorylation
cascade. Addition of seminal plasma to a suspension of spermatozoa
previously incubated for 5 h under capacitating conditions decreased the
level of tyrosine phosphorylation on all proteins in a dose-dependent
manner. In this case, the phosphotyrosine signal did not increase upon
removal of seminal plasma followed by overnight incubation in fresh
capacitating media, indicating that removal of seminal plasma was necessary
but not sufficient for protein tyrosine phosphorylation to occur. These
results indicate that human seminal plasma contains factors that influence
the tyrosine phosphorylation status of human spermatozoa.
相似文献
773.
11Beta-hydroxysteroid dehydrogenase type 2 in human pregnancy and reduced expression in intrauterine growth restriction 总被引:1,自引:0,他引:1
Shams M; Kilby MD; Somerset DA; Howie AJ; Gupta A; Wood PJ; Afnan M; Stewart PM 《Human reproduction (Oxford, England)》1998,13(4):799-804
The type 2 isoform of 11beta-hydroxysteroid dehydrogenase (11beta- HSD2),
which inactivates cortisol (F) to cortisone (E), has been suggested to play
a role in the ontogeny of the fetal pituitary-adrenal axis and also protect
the developing fetus from the deleterious effects of circulating maternal
glucocorticoids. The abundance of 11beta-HSD2 in the placenta and other
fetal tissues was inferred from the F/E ratio in 17 term deliveries in both
umbilical arterial (1.73 +/- 0.24, mean +/- SE) and umbilical venous blood
(1.16 +/- 0.14) compared with adult peripheral venous blood (7.76 +/- 0.57,
n = 70). Using sensitive assays for 11beta-HSD2 and an in-house human
11beta-HSD2 antibody, the expression and activity of this enzyme in fresh
frozen human placenta increased progressively from first (8-12 weeks, n =
16) and second (13- 20 weeks, n = 9) to third trimester (term) pregnancies
(39-40 weeks, n = 50). Placental 11beta-HSD2 activity was significantly
reduced in deliveries complicated by intrauterine growth restriction (IUGR)
[25-36 weeks, n = 12, activity 380 pmol/mg/h median (225-671; 95%
confidence interval)], compared with the term deliveries [888 (725-1362)]
and with appropriately grown pre-term deliveries [27-36 weeks, n = 14,
activity 810 (585-1269)], P < 0.05. In human pregnancy placental
11beta-HSD2 activity increases markedly in the third trimester of pregnancy
at a time when maternal circulating levels of glucocorticoid are rising.
The finding of attenuated placental 11beta-HSD2 activity in IUGR suggests
that glucocorticoids may, in part, contribute to impaired fetal growth and
that this is closely controlled in normal gestation through placental
11beta-HSD2 expression.
相似文献
774.
Erik F Hensen Jeroen C Jansen Maaike D Siemers Jan C Oosterwijk Annette HJT Vriends Eleonora PM Corssmit Jean-Pierre Bayley Andel GL van der Mey Cees J Cornelisse Peter Devilee 《European journal of human genetics : EJHG》2010,18(1):62-66
Germline mutations in SDHD predispose to the development of head and neck paragangliomas, and phaeochromocytomas. The risk of developing a tumor depends on the sex of the parent who transmits the mutation: paragangliomas only arise upon paternal transmission. In this study, both the risk of paraganglioma and phaeochromocytoma formation, and the risk of developing associated symptoms were investigated in 243 family members with the SDHD.D92Y founder mutation. By using the Kaplan–Meier method, age-specific penetrance was calculated separately for paraganglioma formation as defined by magnetic resonance imaging (MRI) and for paraganglioma-related signs and symptoms. Evaluating clinical signs and symptoms alone, the penetrance reached a maximum of 57% by the age of 47 years. When MRI detection of occult paragangliomas was included, penetrance was estimated to be 54% by the age of 40 years, 68% by the age of 60 years and 87% by the age of 70 years. Multiple tumors were found in 65% and phaeochromocytomas were diagnosed in 8% of paraganglioma patients. Malignant paraganglioma was diagnosed in one patient (3%). Although the majority of carriers of a paternally inherited SDHD mutation will eventually develop head and neck paragangliomas, we find a lower penetrance than previous estimates from studies based on predominantly index cases. The family-based study described here emphasizes the importance of the identification and inclusion of clinically unaffected mutation carriers in all estimates of penetrance. This finding will allow a more accurate genetic counseling and warrants a ‘wait and scan'' policy for asymptomatic paragangliomas, combined with biochemical screening for catecholamine excess in SDHD-linked patients. 相似文献