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71.
Summary A rare case of a spinal papillary meningioma in a 19-year-old adolescent is described. Six months after radical resection
the patient showed dissemination along the cerebrospinal pathway. Papillary meningiomas are rare tumours with a relatively
high incidence in childhood. Most papillary meningiomas reported in the literature are considered as aggressive variants of
meningioma with often local recurrence, dissemination in the CSF and metastases to remote sites. This case supports that,
although the histogenesis remains unexplained, papillary meningiomas deserve recognition on the basis of their high morbidity
and mortality. 相似文献
72.
Brahim Housni Rachida Bayad Rachid Cherkab Sa?d Salmi Mohamed Miguil 《Hypertension in pregnancy》2004,23(3):269-273
Diffuse neurological manifestations of preeclampsia are due to endothelial involvement that lead to ischemia, hemorrhage, or edema. We analyzed clinical and radiological features and the course of brainstem ischemic strokes in a preeclampsia patient. We report a case of severe preeclampsia in a 30-year-old woman who was admitted 10 hr after a vaginal delivery at home. The pregnancy was at 39 wk, with no prenatal care. At her admission, she was conscious, and she had tetraparesia, swinging deep tendon reflex testing, drowsiness, and dysarthria; the BP was at 160/100 mmHg and 4 + proteinuria; magnetic resonance imaging revealed brainstem ischemic stroke. The evolution was favorable with symptomatic treatment. The patient was discharged on the 16th day; 2 months later she had a normal recovery. Brainstem strokes are rare. They are frequently due to hemorrhage; sometimes, they can also be ischemic. Their course is favorable. 相似文献
73.
RF Lamont 《BJOG : an international journal of obstetrics and gynaecology》2006,113(S3):96-99
Over the past 15 years, the use of β-agonists has declined worldwide. Following the Royal College of Obstetricians and Gynaecologists guidelines in 2002, clinicians in the UK and beyond were faced with the dilemma of continuing to use β-agonists, desist from using tocolytic therapy completely or choosing to change to atosiban or calcium channel blockers (CCBs). While grade A level 1 evidence exists to show that atosiban is significantly more efficacious than placebo and significantly safer than β-agonists for the treatment of spontaneous preterm labour, the evidence for CCBs, such as nifedipine, is much less robust and no placebo-controlled trials have been performed. Published studies on nifedipine are largely investigator-led studies of small sample size, which lack sufficient power. As a result, most of the evidence has been based on meta-analyses of these studies, which look retrospectively at pooled data and are only as good as the quality of the studies included. In light of this, a tool was developed to produce a systematic review of studies on tocolytic effectiveness, which can and should be applied to all tocolytics and which considered both method- and topic-specific markers of quality. In the process of applying this tool to nifedipine, an extensive literature search identified 31 studies for a systematic review of the quality of nifedipine studies assessed by eight paired reviewers with wide experience in the subject of spontaneous preterm labour and preterm birth. Forty topic- and method-specific items of quality were assessed. The paucity of good quality studies of nifedipine used for the treatment of spontaneous preterm labour should be highlighted in meta-analyses or systematic reviews, which measure efficacy and should limit and influence the degree to which recommendations and guidelines are made on the basis of such studies. 相似文献
74.
A Bognár B Csernus C B?d?r L Reiniger A Szepesi E Tóth L Kopper A Matolcsy 《Leukemia》2005,19(9):1656-1662
To characterize the pathways of bone marrow (BM) involvement of follicular lymphoma (FL), we performed morphological and immunophenotypical analysis of tumor cells from lymph nodes (LNs) and corresponding BMs in 21 patients with FL. In three cases, genealogical trees were constructed based on the immunoglobulin variable region heavy chain (IgV(H)) gene sequences of tumor clones from LNs and BMs. Results showed that FLs within the BMs display identical or lower cytological grades than in the LNs. In the majority of cases, different proportions of tumor cells expressed bcl-2, CD10 and Ki67 in LNs and BMs. Tumor cells in the BM showed ongoing somatic hypermutation of the IgV(H) genes; the distribution of these mutations was highly consistent with antigen selection. The topology of the genealogical trees revealed that different subclones populate the LN and BM and BM infiltration may occur at different points of the clonal evolution of FL. Early descendants of the original tumor clone and derivatives of diversified tumor clones may invade the BM. These results suggest that the BM involvement of FL is associated with intensive clonal selection of tumor cells, and the BM provides a microenvironment similar to the germinal centers of LNs, where tumor cells retain their biological nature. 相似文献
75.
Anne Stuedal Inger Torhild Gram Yngve Bremnes Herman Adlercreutz Marit B Veier?d Giske Ursin 《Cancer epidemiology, biomarkers & prevention》2005,14(9):2154-2159
AIMS: Certain phytoestrogens, such as lignans, may protect against developing breast cancer. Enterolactone is a lignan metabolite produced by the intestinal flora from dietary precursors such as whole grains, vegetables, and fruits. Enterolactone has been shown to have weak estrogenic and antiestrogenic properties. We decided to examine the association between plasma levels of enterolactone and mammographic density, a biomarker for breast cancer risk. METHODS: We included data from postmenopausal women ages 55 and older who participated in a cross-sectional mammogram study in Troms?, Norway. Mammograms, plasma enterolactone measurements, as well as information on anthropometric and hormonal/reproduction factors were available on 616 women. We assessed mammographic density using a previously validated computer-assisted method. We estimated correlation coefficients and conducted multiple regression analyses. RESULTS: Mean mammographic density increased slightly across quartiles of enterolactone; the women in the highest quartile had, on average, 3.1% (absolute difference) higher percentage mammographic density compared with the lowest quartile (P(trend) < 0.01). After adjustment for age, body mass index, number of full-term pregnancies, age at first birth, and use of postmenopausal hormone therapy, the mean difference in density was reduced to 2.0% (P(trend) = 0.05). Results were similar when restricted to the 454 current hormone nonusers. The fully adjusted statistical model explained 28.3% of the total variability in mammographic percentage density, with body mass index contributing 18.2% and enterolactone only 0.9%. CONCLUSION: In our study, higher levels of enterolactone were associated with slightly higher percentage mammographic density. Our results suggest that if higher enterolactone levels reduce the risk of developing breast cancer in postmenopausal women, then this effect is not through lowering mammographic density. 相似文献
76.
Saïd Yous Valérie Wallez Mirabelle Belloir Daniel H. Caignard Christopher R. McCurdy Jacques H. Poupaert 《Medicinal chemistry research》2005,14(3):158-168
In an effort to produce a new pharmacological probe with high affinity and selectivity for the sigma-1 receptor, we have synthesized
a series of original 2(3H)-benzothiazolones utilizing compound 4 [3-(1-piperidinoethyl)-6-propylbenzothiazolin-2-one] as a lead. Receptor binding affinities were determined at sigma-1 and
sigma-2 receptors. The best ligand (9, sigma-1 Ki = 0.56 nM, selectivity ratio >1000) was obtained with an azepine side-chain. When tested on a wide battery of receptors,
including 5HT2A(h), 5HT3(h), α1, α 2, β1, β2, H1, H2, opioids, D1(h), D2(h), 5HT uptake, and DOPA uptake, compound 9 showed submicromolar affinity only for α2 (Ki = 205 nM) and H1 (Ki = 311 nM). 相似文献
77.
Grzybowski A Grzybowski G Druzdz A Zaba R 《Documenta ophthalmologica. Advances in ophthalmology》2001,103(3):187-194
Purpose: The aim of this study is an estimation of the visual evoked potentials (VEP) in patients with psoriasis vulgaris. The role of the nervous system was pointed out in the pathogenesis of psoriasis. Also epidemiologic research confirms that patients with psoriasis are at increased risk of MS development. Materials and methods: A group of 30 psoriatic males aged between 18 and 54 was examined. The results were compared with those obtained from a group of 30 healthy age-matched males and they were correlated with the psoriasis area and severity index (PASI), the skin surface area involved, duration of the disease and duration of the last relapse. In neurological and ophthalmological examinations no pathological symptoms were detected in either group. The VEP examination was executed using pattern reversal (pr) and pattern flash (pf) stimulation. Results: Using pf stimulation, in the group of patients with psoriasis vulgaris, a statistically significant elongation in the latency of P-100 and reduction of response amplitude, not related to the PASI, nor the skin surface area involved, nor duration of the last relapse, were observed. Conclusions: The results of the study indicate subclinical damage of the visual pathway in patients with psoriasis vulgaris. 相似文献
78.
Fanny Varenne Ali Makky Mireille Gaucher-Delmas Frédéric Violleau Christine Vauthier 《Pharmaceutical research》2016,33(5):1220-1234
Purpose
Evaluation of particle size distribution (PSD) of multimodal dispersion of nanoparticles is a difficult task due to inherent limitations of size measurement methods. The present work reports the evaluation of PSD of a dispersion of poly(isobutylcyanoacrylate) nanoparticles decorated with dextran known as multimodal and developed as nanomedecine.Methods
The nine methods used were classified as batch particle i.e. Static Light Scattering (SLS) and Dynamic Light Scattering (DLS), single particle i.e. Electron Microscopy (EM), Atomic Force Microscopy (AFM), Tunable Resistive Pulse Sensing (TRPS) and Nanoparticle Tracking Analysis (NTA) and separative particle i.e. Asymmetrical Flow Field-Flow Fractionation coupled with DLS (AsFlFFF) size measurement methods.Results
The multimodal dispersion was identified using AFM, TRPS and NTA and results were consistent with those provided with the method based on a separation step prior to on-line size measurements. None of the light scattering batch methods could reveal the complexity of the PSD of the dispersion.Conclusions
Difference between PSD obtained from all size measurement methods tested suggested that study of the PSD of multimodal dispersion required to analyze samples by at least one of the single size particle measurement method or a method that uses a separation step prior PSD measurement.79.
80.
MarcOlivier Pilon Grgoire Leclair Essaïd Oussaïd Isabelle StJean Martin Jutras MarieJose Gaulin Ian Mongrain David Busseuil Jean Lucien Rouleau JeanClaude Tardif MariePierre Dub Simon de Denus 《CTS Clinical and Translational Science》2022,15(8):2024
ABCG2 is a gene that codes for the human breast cancer resistance protein (BCRP). It is established that rs2231142 G>T, a single nucleotide polymorphism of the ABCG2 gene, is associated with gout and poor response to allopurinol, a uric acid‐lowering agent used to treat this condition. It has also been suggested that oxypurinol, the primary active metabolite of allopurinol, is a substrate of the BCRP. We thus hypothesized that carrying the rs2231142 variant would be associated with decreased oxypurinol concentrations, which would explain the lower reduction in uric acid. We performed a cross‐sectional study to investigate the association between the ABCG2 rs2231142 variant and oxypurinol, allopurinol, and allopurinol riboside concentrations in 459 participants from the Montreal Heart Institute Hospital Cohort. Age, sex, weight, use of diuretics, and estimated glomerular filtration rate were all significantly associated with oxypurinol plasma concentration. No association was found between rs2231142 and oxypurinol, allopurinol and allopurinol riboside plasma concentrations. Rs2231142 was not significantly associated with daily allopurinol dose in the overall population, but an association was observed in men, with T carriers receiving higher doses. Our results do not support a major role of ABCG2 in the pharmacokinetics of allopurinol or its metabolites. The underlying mechanism of the association between rs2231142 and allopurinol efficacy requires further investigation. Study Highlights
- WHAT IS THE CURRENT KNOWLEDGE ON THE TOPIC?
- WHAT QUESTION DID THIS STUDY ADDRESS?
- WHAT DOES THIS STUDY ADD TO OUR KNOWLEDGE?
- HOW MIGHT THIS CHANGE CLINICAL PHARMACOLOGY OR TRANSLATIONAL SCIENCE?