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排序方式: 共有383条查询结果,搜索用时 15 毫秒
91.
92.
M-J Castro AH Stam C Lemos B de Vries KRJ Vanmolkot J Barros GM Terwindt RR Frants J Sequeiros MD Ferrari JM Pereira-Monteiro & AMJM van den Maagdenberg 《Cephalalgia : an international journal of headache》2009,29(3):308-313
Almost all mutations in the SCN1A gene, encoding the α1 subunit of neuronal voltage-gated NaV 1.1 sodium channels, are associated with severe childhood epilepsy. Recently, two mutations were identified in patients with pure familial hemiplegic migraine (FHM). Here, we identified a novel SCN1A L263V mutation in a Portuguese family with partly co-segregating hemiplegic migraine and epilepsy. The L263V mutation segregated in five FHM patients, three of whom also had epileptic attacks, occurring independently from their hemiplegic migraine attacks. L263V is the first SCN1A mutation associated with FHM and co-occurring epilepsy in multiple mutation carriers, and is the clearest molecular link between migraine and epilepsy thus far. The results extend the clinical spectrum associated with SCN1A mutations and further strengthen the molecular evidence that FHM and epilepsy share, at least in part, similar molecular pathways. 相似文献
93.
94.
Visual inspection as a cervical cancer screening method in a primary health care setting in Africa 总被引:3,自引:0,他引:3
Sangwa-Lugoma G Mahmud S Nasr SH Liaras J Kayembe PK Tozin RR Drouin P Lorincz A Ferenczy A Franco EL 《International journal of cancer. Journal international du cancer》2006,119(6):1389-1395
We evaluated the feasibility and performance of visual inspection with acetic acid (VIA) and Lugol's iodine (VILI) for cervical cancer screening in a primary health-care setting in Kinshasa, Congo. Women (1,528) aged > or =30 years were screened independently by nurses and physicians by VIA and VILI and Pap cytology. Biopsy samples were obtained from women with abnormal colposcopies and from 290 randomly chosen women with normal colposcopy. Cytological and histological examinations were performed in Lyon and Montreal, respectively. The prevalence of cervical intraepithelial neoplasia (CIN) of grades 1, 2 and 3 was 4.5, 1.3 and 4%, respectively. Using biopsy as the reference, the sensitivity, specificity and negative predictive value (NPV) for > or =CIN 2 for VIA-nurse were 55.5% (95% CI: 34.7-76.2), 64.6% (95% CI: 62.0-67.1) and 96.8% (95% CI: 93.5-98.7), respectively. The corresponding values for VILI-nurse were 44.0% (95% CI: 24.2-63.8), 74.6% (95% CI: 72.3-76.9) and 96.7% (95% CI: 93.7-98.6). The equivalent parameters for physicians were 71.1% (95% CI: 46.7-95.5), 71.3% (95% CI: 68.9-73.6) and 98.6% (95% CI: 96.0-99.7) for VIA and 68.3% (95% CI: 42.5-94.0), 76.2% (95% CI: 74.0-78.4) and 97.2% (95% CI: 95.3-98.5) for VILI. The sensitivity of cytology ranged between 31 and 72%, depending on the abnormality threshold used to define positivity, with a corresponding specificity range of 94-99% and a NPV range of 97-99%. Our results show that VIA and VILI performed by nurses and physicians are slightly more sensitive but less specific than Pap cytology across multiple combinations of test and lesion thresholds. Given their lower cost and easy deployment, visual inspection methods merit further assessment as cervical cancer screening methods for low-resource countries. 相似文献
95.
Characterization of four N-3-thymidine adducts formed in vitro by the reaction of thymidine and butadiene monoxide 总被引:1,自引:0,他引:1
Four products were characterized from the reaction of thymidine with
butadiene monoxide (BM), a known human mutagen and possible human
carcinogen. These products were purified by HPLC and characterized as
diastereomeric pairs of N-3-(1-hydroxy-3-buten-2-yl)thymidine and N-3-
(2-hydroxy-3-buten-1-yl)thymidine based upon their UV spectra, 1H NMR and
fast atom bombardment mass spectra. Incubation of thymidine with an excess
of BM at pH 7.4 and 37 degrees C allowed calculation of the
pseudo-first-order kinetic rate constants for the adduct formation, but
when these rate constants were compared with the rates we previously
determined with guanosine, adenosine and deoxycytidine, the results
suggested a lower reactivity with thymidine in comparison with the other
nucleosides. When incubations were carried out at lower BM concentrations,
the formation of adducts appeared to be linearly dependent on BM
concentration. The four thymidine adducts were completely stable for 1 week
when incubated at 37 degrees C in pH 7.4 phosphate buffer. These results
suggest that the interactions of BM with thymidine may play a role in the
molecular mechanisms of mutagenesis and carcinogenesis of BM.
相似文献
96.
97.
Simeone JF; Edelman RR; Stark DD; Wittenberg J; White EM; Butch RJ; Mueller PR; Brady TJ; Ferrucci JT Jr 《Radiology》1985,157(2):437-441
Eight healthy volunteers and 11 patients with pancreatic abnormalities were studied using a conventional body coil and a prototype magnetic resonance (MR) surface coil. Final pathologic diagnoses included carcinoma of the head (six), body (one), and tail of the pancreas (two) and chronic pancreatitis (two). In surface coil images of the volunteers, the body and tail of the pancreas was visualized in all cases but one, and the pancreatic duct was seen in five of eight cases. In-plane spatial resolution of 0.9 X 0.9 mm and 5-mm section thickness was obtained. At the same time, pancreatic surface coil images had a twofold improvement in the signal-to-noise ratio (SNR) compared with body coil images. T1-weighted spin-echo images gave greater SNR, reduced motion artifacts, provided superior anatomic detail, and offered more diagnostic information than comparable T2-weighted images. Significant abnormalities detected only by surface coil imaging included a small tumor surrounded by reactive edema and periglandular tumor invasion. This study demonstrates that surface coil imaging of the pancreas not only is feasible but provides an improved method for examining the pancreas by MR. 相似文献
98.
99.
Plasma-derived vitamin D binding protein (DBP) is an important physiologic regulator of the neutrophil chemotactic response to activated complement. A cell-associated form of DBP has been observed in numerous cell types. We now report that mature, circulating human neutrophils also contain cell-associated DBP. Immunofluorescence studies of normal untreated neutrophils showed the presence of DBP on the cell surface. Western blotting of detergent-soluble neutrophil lysates with a polyclonal anti-DBP showed two major immunoreactive bands, one with an apparent molecular weight of 56 Kd (identical to purified plasma-derived DBP) and a second less prominent band at 12 to 14 Kd. Quantitation of the immunoreactive bands by video densitometry indicated that normal human neutrophils contain 1.5 +/- 0.8 ng DBP/10(6) cells (n = 9). Immunoprecipitation of detergent-soluble lysates with the polyclonal anti-DBP showed only the 56-Kd form by Western blotting. In contrast, a monoclonal anti-DBP immunoprecipitated the 12 to 14 Kd form of DBP from lysates of surface-radioiodinated cells. Western blots of subcellular fractions showed that immunoreactive bands were found in the specific (secondary) granule and plasma-membrane fractions. In addition, pretreatment of neutrophils with 10 nmol/L phorbol myristate acetate (PMA) resulted in approximately a 50% reduction in the amount of DBP in both the specific granule and plasma-membrane fractions. Finally, analysis of the cell- free supernates showed that DBP was spontaneously released into the extracellular milieu: moreover, this release was enhanced if the cells were first stimulated with C5a, formyl-norleucyl-leucyl-phenylalanine (fNLP) or PMA. 相似文献
100.
To overcome the problem of recurrence of stenosis after vascular balloon dilatations, we developed an expandable, intraluminal graft that allows dilatation of the lesion and simultaneous placement of a supportive endoprosthesis to prevent recoil of the arterial wall. The graft is made of continuous, woven, stainless steel wire. The resulting tubular mesh has a wall thickness of 200-450 micron and 80% open surface. The grafts, mounted on angioplasty catheters, are introduced through 8-12-F Teflon sheaths. Eleven grafts of 6, 8, and 10 mm in diameter by 20 mm long were placed in the aorta, common carotid, superior mesenteric, iliac, and renal arteries of dogs. Six grafts showed no stenosis in follow-up studies of up to 8 weeks. Two grafts had moderate stenosis as a result of neointimal hyperplasia. Two partial and one complete graft thrombosis occurred in nonheparinized animals in which the graft outflow was restricted. Anticoagulant was not used on a long-term basis. Light and electron microscopy studies showed complete covering of the graft's inner surface by endothelium at 3 weeks. 相似文献