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11.
Intracranial and spinal haemangiopericytomas are uncommon, durally based tumours. They macroscopically resemble meningiomas
but are distinct histologically, have a more aggressive natural history and require different management. We present a pictorial
review illustrating the radiological manifestations of these tumours that will aid in their preoperative identification. 相似文献
12.
Novel proteins with binding specificity for DNA CTG repeats and RNA CUG repeats: implications for myotonic dystrophy 总被引:7,自引:6,他引:7
While an unstable CTG triplet repeat expansion is responsible for myotonic
dystrophy, the mechanism whereby this genetic defect induces the disease
remains unknown. To detect proteins binding to CTG triplet repeats, we
performed bandshift analysis using as probes double- stranded DNA fragments
having CTG repeats [ds(CTG)6-10] and single- stranded oligonucleotides
having CTG repeats ss(CTG)8 or RNA CUG triplet repeats (CUG)8. The source
of protein was nuclear and cytoplasmic extracts of HeLa cells, fibroblasts
and myotubes. Proteins binding to the double-stranded DNA repeat
[ds(CTG)6-10], were inhibited by nonlabeled ds(CTG)6-10, but not by a
non-specific DNA fragment (USF/AD-ML). Another protein binding to ssCTG
probe and RNA CUG probe was inhibited by nonlabeled (CTG)8 and (CUG)8.
Nonlabeled oligos with different triplet repeat sequences, ss(CAG)8 or
ss(CGG)8, did not inhibit binding to the ss(CTG)8 probe. However, when
labeled as probes, the (CAG)8 and (CGG)8 bound to proteins distinct from
the CTG proteins and binding was inhibited by nonlabeled (CAG)8 or (CGG)8
respectively. The protein binding only to the RNA repeat (CUG)8 was
inhibited by nonlabeled (CUG)8 but not by nonlabeled single- or
double-stranded CTG repeats. Furthermore, the CUG-BP exhibited no binding
to an RNA oligonucleotide of triplet repeats of the same length but having
a different sequence, CGG. The CUG binding protein was localized to the
cytoplasm, whereas dsDNA binding proteins were localized to the nuclear
extract. Thus, several trinucleotide binding proteins exist and their
specificity is determined by the triplet sequence. The novel protein,
CUG-BP, is particularly interesting since it binds to triplet repeats known
to be present in myotonin protein kinase mRNA which is responsible for
myotonic dystrophy.
相似文献
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16.
Bersinger NA; Brandenberger A; Berger E; Baumann CK; Birkhauser MH 《Human reproduction (Oxford, England)》1998,13(7):1962-1967
We have previously observed the repeated presence of low but detectable
amounts of the trophoblast marker pregnancy-specific beta1-glycoprotein
(SP1) in the serum of some women undergoing in-vitro fertilization (IVF)
treatment around the time of oocyte retrieval. The occurrence of these
signals seemed to be restricted to a defined group of patients which also
showed a lower pregnancy success rate in a preliminary study. To test our
hypothesis we have analysed 173 consecutive cycles leading to an embryo
transfer. Fifty-four cycles (31%) had a serum SP1 level of at least 0.1
ng/ml between days embryo transfer -5 and embryo transfer (group A). Five
pregnancies were obtained in this group (pregnancy rate = 9.3%), while in
group B, defined by the absence of detectable SP1 before embryo transfer
(119 cycles), 36 ongoing pregnancies were achieved (30.3%). Ten of the 41
pregnancies were achieved in 33 first-time non-pregnant patients undergoing
further attempts during the study period. Again the pregnancy rate was
higher in the first-time group B women (9/23 versus 1/10 for group A).
Patients tended to remain in their groups A or B, the latter being
associated with a better immediate as well as subsequent chance for
pregnancy. Group A cycles had a significantly lower endometrial thickness
two days before oocyte retrieval than group B (P = 0.0011). We postulate
that the presence of an unknown, maternal and progesterone- or follicle
stimulating hormone-independent factor in some patients could stimulate
tonic ectopic SP1 synthesis and at the same time negatively influence
endometrial development.
相似文献
17.
NJ Hoogenraad JD Mitchell NA Don TM Sutherland AC Mc Leay 《Archives of disease in childhood》1980,55(4):292-295
The activity of urea cycle enzymes was assayed in duodenal biopsy specimens obtained from a female infant who presented with neonatal hyperammonaemia. All enzyme levels were normal except N-acetyl glutamate-dependent carbamyl phosphate synthetase 1 (CPS1) which was half the mean activity in normal control specimens. A similar deficiency of CPS1 was also shown in duodenal specimens from the patient's mother who became slightly symptomatic after relatively high protein meals and during pregnancy, and had spontaneously modified her diet to one with protein restriction. The patient is growing normally on a dietary regimen similar to that spontaneously adopted by her mother. Urea cycle enzyme activity in the duodenal biopsy material from the controls was similar to that found in the normal human liver and appears to have distinct advantages as a means of assaying for urea cycle defects in patients with hyperammonaemia and their relatives. 相似文献
18.
目的探讨在老年2型糖尿病合并缺血性心脏病患者中尿微量蛋白在加重缺血性心脏病进展方面的作用。方法将66例老年2型糖尿病合并缺血性心脏病患者按24h尿微量蛋白排泄量分为:尿微量蛋白正常组及尿微量蛋白阳性组,分别对血脂、空腹血糖、血清胰岛素、胰岛素敏感指数、纤维蛋白原、颈动脉内-中膜厚度、颈总动脉粥样硬化等级积分、硬化斑块指数、心脏彩超室间隔厚度及射血分数等加重缺血性心脏病进展等指标进行比较分析。结果66例老年2型糖尿病合并缺血性心脏病患者尿微量蛋白阳性组高密度脂蛋白、载脂蛋白A、胰岛素敏感指数、年龄、纤维蛋白原、硬化斑块指数、颈总动脉粥样硬化等级积分、室间隔厚度及射血分数显著高于尿微量蛋白阴性组(P<0.05,P<0.01)。结论尿微量蛋白的出现能够加速糖尿病合并缺血性心脏病的发展进程,它的出现预示着缺血性心脏病的预后不良。 相似文献
19.
NA Bridges JA Christopher PC Hindmarsh CG Brook 《Archives of disease in childhood》1994,70(2):116-118
The aetiology of 197 girls and 16 boys presenting with sexual precocity was reviewed. Ninety one girls and four boys had central precocious puberty (M:F 23:1); a cause was identified in all the boys but in only six girls. All boys with precocious puberty need detailed investigation; in girls investigation should be based on clinical findings, particularly the consonance of puberty. 相似文献
20.
Extracts of Monascusus Purpureus beyond Statins——Profile of Efficacy and Safety of the Use of Extracts of Monascus Purpureus 下载免费PDF全文
BIANCHI Antonio 《中国结合医学杂志》2005,(4)
Monascus purpureus is a fungus that has been tradi-tionally used in China for thousands of years to produce ricewine . Traditionally the fungus is used to ferment non-gluti-nous cooking of rice ,to produce a kind of famous red ricewine .Its main traditional indications consist of disordersdue to the accumulation of fats (nosologically linked withthe problems of stasis of circulation in traditional Chinesemedicine) ,liver disorders and some forms of tumor as ithelps i mprove the circulation of … 相似文献