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151.
We present two pregnancies associated with normal live births and the unusual concomitance of chorangioma and placental vascular malformation with mesenchymal hyperplasia. The enlarged placenta had the characteristic findings of chorangioma, dilated and varicose chorionic vessels and multiple vesicle-like villi containing hyaluronic acid. The vesicle-like villi showed diploid cellular DNA contents. Molecular genetic analysis using the polymerase chain reaction amplification of polymorphic microsatellite markers confirmed genetic identity among the chorangioma, the vesicle-like villi and the fetus. Both pregnancies were complicated by polyhydramnios, pre-term labour and prematurity. One neonate suffered from anaemia and thrombocytopenia. Another neonate suffered from haemangiomatosis. Our cases demonstrate that concomitant chorangioma and placental mesenchymal hyperplasia are genetically identical to the fetus and can coexist with a normal viable fetus. Since haemangiomas, chorangiomas, chorionic vessels and villi mesenchymal cells are all derived from the mesoderm, a combination of fetal haemangiomas, placental vascular malformation, chorangiomas and placental mesenchymal hyperplasia may represent a mixed form of congenital malformation of the mesoderm.   相似文献   
152.
A randomized trial was carried out to investigate the effect of 12 months administration of the gonadotrophin-releasing hormone agonist (GnRHa) Zoladex in combination with either placebo or medroxyprogesterone acetate (MPA) from the third month. Bone density, markers of bone resorption, symptoms and uterine volume were monitored in 24 women with symptomatic fibroids or menstrual problems. A total of 21 women were recruited to act as controls for the assessment of bone parameters. Vasomotor side-effects were reduced significantly in the MPA-treated group. The reduction in uterine volume in women with fibroids was not impaired by the addition of MPA. The bone markers osteocalcin and alkaline phosphatase were assessed in plasma, and the cross-links pyridinoline and deoxypyridinoline measured in urine. Changes in these markers are reported which suggest increases in bone resorption during the period of observation. Bone mineral density (BMD) was assessed by dual energy X-ray absorptiometry at the spine and forearm. The net reduction in BMD at the spine in the treated groups was 4.30 +/- 0.59% at 6 months and 7.50 +/- 0.78% at 1 year, with no change in the control group. No change was seen in forearm BMD. No protective effect was observed when MPA was added. At 1 year after the completion of treatment, BMD remained significantly below baseline, and this has implications for the prolonged use of GnRHa.   相似文献   
153.

Background  

A trial was commissioned to evaluate the effectiveness of larval therapy to debride and heal sloughy and necrotic venous leg ulcers. Larval therapy in the trial was to be delivered in either loose or bagged form. Researchers were concerned that resistance to larval therapy may threaten the feasibility of the trial. Additionally there was concern that the use of larval therapy may require a larger effect size in time to healing than originally proposed by the investigators.  相似文献   
154.
The Survival Motor Neuron (SMN) gene shows deletions in the majority of patients with Spinal Muscular Atrophy (SMA), a disease of motor neuron degeneration. To date only two missense mutations have been reported in SMN in patients with SMA. The fact that no SMN-homologues have been forthcoming from data-base searching has resulted in a lack of hypotheses concerning the structural and functional consequences of these mutations. Recently SMN has been shown to interact with heterogeneous nuclear ribonucleoproteins (hnRNPs) suggesting a role in mRNA metabolism. We describe a novel missense mutation and the subsequent identification of a triplicated tyrosine-glycine (Y-G) peptide sequence at the C-terminal of SMN which encompasses each of the three predicted amino acid sequence substitutions. We have identified apparent orthologues of SMN in Caenorhabditis elegans and Schizosaccharomyces pombe. These sequences retain the highly conserved Y-G motif and provide additional support for a role of SMN in mRNA metabolism.   相似文献   
155.
156.
The epilepsies are a group of disorders characterised by recurrent seizures caused by episodes of abnormal neuronal hyperexcitability involving the brain. Up to 60 million people are affected worldwide and genetic factors may contribute to the aetiology in up to 40% of patients. The most common human genetic epilepsies display a complex pattern of inheritance. These are categorised as idiopathic in the absence of detectable structural or metabolic abnormalities. Juvenile myoclonic epilepsy (JME) is a distinctive and common variety of familial idiopathic generalised epilepsy (IGE) with a prevalence of 0.5- 1.0 per 1000 and a ratio of sibling risk to population prevalence (lambda(s)) of 42. The molecular genetic basis of these familial idiopathic epilepsies is entirely unknown, but a mutation in the gene CHRNA4, encoding the alpha4 subunit of the neuronal nicotinic acetylcholine receptor (nAChR), was recently identified in a rare Mendelian variety of idiopathic epilepsy. Chromosomal regions harbouring genes for nAChR subunits were therefore tested for linkage to the JME trait in 34 pedigrees. Significant evidence for linkage with heterogeneity was found to polymorphic loci encompassing the region in which the gene encoding the alpha7 subunit of nAChR (CHRNA7) maps on chromosome 15q14 (HLOD = 4.4 at alpha = 0.65; Z(all) = 2.94, P = 0.0005). This major locus contributes to genetic susceptibility to JME in a majority of the families studied.   相似文献   
157.
We purified by fractionation on 10-40% glycerol gradients, 26S proteasomes from normal human spermatozoa. These proteasomes, which participate in the ATP-dependent degradation of ubiquitinated proteins, share a similar sedimentation coefficient to those purified from other human tissues. Fluorogenic peptide assays reveal they have chymotrypsin, trypsin and peptidyl-glutamyl-like peptide hydrolysing activities; the chymotrypsin activity is ablated by the specific 26S proteasome inhibitor MG132. Confirmation that these large proteases are 26S proteasomes is provided by detection of the 20S proteasome subunits HC2, XAPC7, RN3 and Z and regulatory ATPases MSS1, TBP1, SUG1 and SUG2 by Western analyses with monoclonal antisera. These antigens are found only in the gradient fractions enriched in proteolytic activities. We have also shown that, although mature spermatozoa from mice have considerably reduced amounts of a ubiquitin-conjugating enzyme (E2) and ubiquitin-protein conjugates in comparison with less mature germ cells, they retain relatively high values of 26S proteasome activity. This suggests that proteasomes may have further roles to play in normal sperm physiology.   相似文献   
158.
159.
Oral Diseases (2012) 19 , 65–72 Objective: Heat‐shock protein 27 (hsp27) has been implicated in several biological events. In this experimental study, we aimed at analysing, for the first time, the expression of hsp27 in the diverse stages of oral lichen planus (OLP) lesions. Materials and methods: Thirty‐six biopsy specimens of patients with OLP and 10 of healthy patients were selected. OLP specimens were divided into three groups: G1 – moderate or mildly active OLP; G2 – active or moderately active atrophic OLP; G3 – mild or inactive atrophic OLP. Hsp27 expression was analysed by immunohistochemistry (staining intensity and percentage of stained cells), and results of staining were compared between the different groups. Gender, age and anatomical location were also studied. Results: In the basal layer, an increase of hsp27 expression in both G2 and G3 was observed when compared to G1 and control group. In contrast, a decrease of hsp27 expression in the superficial layer was observed in all groups when compared to control group. Conclusion: The increased expression of Hsp27 in the basal layer observed during the OLP evolution and the less staining in the superficial layers in all cases of OLP suggest that hsp27 may have a role in the OLP pathogenesis.  相似文献   
160.
BACKGROUND:In this phase II trial,we investigated the efficacy of a metronomic temozolomide schedule in the treatment of recurrent malignant gliomas(MGs).METHODS:Eligible patients received daily temozolomide(50 mg/m2)continuously until progression.The primary endpoint was progression-free survival rate at 6 months in the glioblastoma cohort(N=37).In an exploratory analysis,10 additional recurrent grade III MG patients were enrolled.Correlative studies included evaluation of 76 frequent mutations in glioblastoma(iPLEX assay,Sequenom)aiming at establishing the frequency of potentially"drugable"mutations in patients entering  相似文献   
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