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排序方式: 共有2972条查询结果,搜索用时 15 毫秒
61.
Survey of CAG/CTG repeats in human cDNAs representing new genes: candidates for inherited neurological disorders 总被引:3,自引:2,他引:3
Neri C; Albanese V; Lebre AS; Holbert S; Saada C; Bougueleret L; Meier-Ewert S; Le Gall I; Millasseau P; Bui H; Giudicelli C; Massart C; Guillou S; Gervy P; Poullier E; Rigault P; Weissenbach J; Lennon G; Chumakov I; Dausset J; Lehrach H; Cohen D; Cann HM 《Human molecular genetics》1996,5(7):1001-1009
62.
63.
KM Kanal NJ Hangiandreou AM Sykes HE Eklund PA Araoz JA Leon BJ Erickson 《Journal of digital imaging》2002,14(1):30-37
The aims of this work were to measure the accuracy of one continuous speech recognition product and dependence on the speaker's
gender and status as a native or nonnative English speaker, and evaluate the product's potential for routine use in transcribing
radiology reports. IBM MedSpeak/Radiology software, version 1.1 was evaluated by 6 speakers. Two were nonnative English speakers,
and 3 were men. Each speaker dictated a set of 12 reports. The reports included neurologic and body imaging examinations performed
with 6 different modalities. The dictated and original report texts were compared, and error rates for overall, significant,
and subtle significant errors were computed. Error rate dependence on modality, native English speaker status, and gender
were evaluated by performing ttests. The overall error rate was 10.3 +/- 3.3%. No difference in accuracy between men and women
was found; however, significant differences were seen for overall and significant errors when comparing native and nonnative
English speakers (P = .009 and P = .008, respectively). The speech recognition software is approximately 90% accurate, and
while practical implementation issues (rather than accuracy) currently limit routine use of this product throughout a radiology
practice, application in niche areas such as the emergency room currently is being pursued. This methodology provides a convenient
way to compare the initial accuracy of different speech recognition products, and changes in accuracy over time, in a detailed
and sensitive manner. 相似文献
64.
Autoantibodies to ganglionic acetylcholine receptors in autoimmune autonomic neuropathies 总被引:15,自引:0,他引:15
Vernino S Low PA Fealey RD Stewart JD Farrugia G Lennon VA 《The New England journal of medicine》2000,343(12):847-855
BACKGROUND: Idiopathic autonomic neuropathy is a severe, subacute disorder with a presumed autoimmune basis. It is indistinguishable from the subacute autonomic neuropathy that may accompany lung cancer or other tumors. Autoantibodies specific for nicotinic acetylcholine receptors in the autonomic ganglia are potentially pathogenic and may serve as serologic markers of various forms of autoimmune autonomic neuropathy. METHODS: We tested serum from 157 patients with a variety of types of dysautonomia. Immunoprecipitation assays with iodine-125-labeled epibatidine and solubilized human neuroblastoma acetylcholine receptors were used to detect autoantibodies that bound to or blocked ganglionic receptors. RESULTS: Ganglionic-receptor-binding antibodies were found in 19 of 46 patients with idiopathic or paraneoplastic autonomic neuropathy (41 percent), in 6 of 67 patients with postural tachycardia syndrome, idiopathic gastrointestinal dysmotility, or diabetic autonomic neuropathy (9 percent), and in none of 44 patients with other autonomic disorders. High levels of the binding antibodies correlated with more severe autonomic dysfunction (including the presence of tonic pupils). Levels of these antibodies decreased in patients who had clinical improvement. All seven patients with ganglionic-receptor-blocking antibodies had ganglionic-receptor-binding antibodies and had idiopathic or paraneoplastic autonomic neuropathy. CONCLUSIONS: Seropositivity for antibodies that bind to or block ganglionic acetylcholine receptors identifies patients with various forms of autoimmune autonomic neuropathy and distinguishes these disorders from other types of dysautonomia. The positive correlation between high levels of ganglionic-receptor antibodies and the severity of autonomic dysfunction suggests that the antibodies have a pathogenic role in these types of neuropathy. 相似文献
65.
Canfield MC; Tamarappoo BK; Moses AM; Verkman AS; Holtzman EJ 《Human molecular genetics》1997,6(11):1865-1871
Congenital nephrogenic diabetes insipidus (NDI) is a rare disease caused
most often by mutations in the vasopressin V2 receptor (AVPR2). We studied
a family which included a female patient with NDI with symptoms dating from
infancy. The patient responded to large doses of desmopressin (dDAVP) which
decreased urine volume from 10 to 4 I/day. Neither the parents nor the
three sisters were polyuric. The patient was found to be a compound
heterozygote for two novel recessive point mutations in the aquaporin-2
(AQP2) gene: L22V in exon 1 and C181W in exon 3. Residue Cys181 in AQP2 is
the site for inhibition of water permeation by mercurial compounds and is
located near to the NPA motif conserved in all aquaporins. Osmotic water
permeability (Pf) in Xenopus oocytes injected with cRNA encoding C181W-AQP2
was not increased over water control, while expression of L22V cRNA
increased the Pf to approximately 60% of that for wild-type AQP2.
Co-injection of the mutant cRNAs with the wild-type cRNA did not affect the
function of the wild-type AQP2. Immunolocalization of AQP2-transfected CHO
cells showed that the C181W mutant had an endoplasmic reticulum-like
intracellular distribution, whereas L22V and wild-type AQP2 showed endosome
and plasma membrane staining. Water permeability assays showed a high Pf in
cells expressing wild-type and L22V AQP2. This study indicates that AQP2
mutations can confer partially responsive NDI.
相似文献
66.
Debelenko LV; Brambilla E; Agarwal SK; Swalwell JI; Kester MB; Lubensky IA; Zhuang Z; Guru SC; Manickam P; Olufemi SE; Chandrasekharappa SC; Crabtree JS; Kim YS; Heppner C; Burns AL; Spiegel AM; Marx SJ; Liotta LA; Collins FS; Travis WD; Emmert-Buck MR 《Human molecular genetics》1997,6(13):2285-2290
Lung carcinoids occur sporadically and rarely in association with multiple
endocrine neoplasia type 1 (MEN1). There are no well defined genetic
abnormalities known to occur in these tumors. We studied 11 sporadic lung
carcinoids for loss of heterozygosity (LOH) at the locus of the MEN1 gene
on chromosome 11q13, and for mutations of the MEN1 gene using dideoxy
fingerprinting. Additionally, a lung carcinoid from a MEN1 patient was
studied. In four of 11 (36%) sporadic tumors, both copies of the MEN1 gene
were inactivated. All four tumors showed the presence of a MEN1 gene
mutation and loss of the other allele. Observed mutations included a 1 bp
insertion, a 1 bp deletion, a 13 bp deletion and a single nucleotide
substitution affecting a donor splice site. Each mutation predicts
truncation or potentially complete loss of menin. The remaining seven
tumors showed neither the presence of a MEN1 gene mutation nor 11q13 LOH.
The tumor from the MEN1 patient showed LOH at chromosome 11q13 and a
complex germline MEN1 gene mutation. The data implicate the MEN1 gene in
the pathogenesis of sporadic lung carcinoids, representing the first
defined genetic alteration in these tumors.
相似文献
67.
Maša Davidović Nadine Zielonke Iris Lansdorp-Vogelaar Nereo Segnan Harry J. de Koning Eveline AM. Heijnsdijk 《Value in health》2021,24(3):353-360
ObjectivesTo quantify the impact of mammography-based screening on the quality of life, disability-adjusted life years (DALYs) averted or quality-adjusted life years (QALYs) gained can be used. We aimed to assess whether the use of DALYs averted or QALYs gained will lead to different cost-effective screening strategies.MethodsUsing the microsimulation model MISCAN, we simulated different breast cancer screening strategies varying in starting age (starting at 45, 47, and 50 years), stopping age (stopping at 69, 72, and 74 years), and frequency (annual [A], biennial [B], combination of both [A + B], and triennial [T]). In total, we defined 24 different breast cancer screening strategies, including no screening as a reference strategy. We calculated incremental cost-effectiveness ratios (ICERs) and compared which strategies were on the efficiency frontiers for DALYs and QALYs.ResultsBreast cancer screening averted between 46.00 and 105.58 DALYs and gained between 28.69 and 64.50 QALYs per 1000 women. For DALYs there were 5 strategies on the efficiency frontier (T50-69, T50-74, T45-74, B45-74, and A45-74). The same strategies plus one (B45-72) were on the efficiency frontier for QALYs.ConclusionsUsing DALYs averted instead of QALYs gained to assess the effects on quality of life from breast cancer screening in the Dutch population yields differences in ICERs, but almost the same strategies were on the efficiency frontiers. Whether the choice in outcome measure leads to a difference in optimal policy depends on the cost-effectiveness threshold. 相似文献
68.
John Lennon Silva Cunha Carla Isabelly Rodrigues-Fernandes Ciro Dantas Soares Celeste Snchez-Romero Pablo Agustin Vargas Cleverson Luciano Trento Bruno Augusto Benevenuto de Andrade Sílvia Ferreira de Sousa Ricardo Luiz Cavalcanti de Albuquerque-Júnior 《Head and neck pathology》2021,15(1):303
Myofibroma (MF) is a benign mesenchymal myofibroblast-derived tumor, which occurs most frequently in children, and rarely affects the maxilla. We reported a case of an aggressive intraosseous lesion found in the maxilla of a 9-year-old female child. Intraorally, the swelling extended from tooth 12 to 16, causing displacement of teeth 13, 14, and 15. Computed tomography revealed a large osteolytic lesion causing thinning and cortical erosion. Microscopically, the lesion showed a proliferation of spindle-shaped cells, with elongated nuclei and eosinophilic cytoplasm, arranged in interlaced fascicles. The immunohistochemical analysis revealed cytoplasmic positivity for α-SMA and HHF-35, and negativity for desmin, laminin, S-100, β-catenin, and CD34. Ki-67 was positive in 8% of tumor cells. The diagnosis was MF. Herein, we describe an additional case of central MF arising in the maxilla, including clinical, imaging, microscopical, and immunohistochemical features, as well as a review of the literature. 相似文献
69.
Stinson LW Lennon RL Adams RA Morrey BF 《Journal of shoulder and elbow surgery / American Shoulder and Elbow Surgeons ... [et al.]》1993,2(4):182-189
A prospective study was done on 99 consecutive patients who underwent distraction elbow arthroplasty and postoperative continuous passive motion from 1986 to 1992. Postoperative axillary catheter infusion in 73 patients was compared with patient-controlled analgesia-opioid treatment in 26 patients. Group comparisons for analgesia, complications, time to initiation, and tolerance of postoperative continuous passive motion were made. The postoperative axillary catheter infusion group was more comfortable and had better postoperative continuous passive motion compliance than did the patient-controlled analgesia-opioid group. The postoperative axillary catheter infusion group had a 2.7% (2 of 73) incidence of respiratory toxicity. There was an 11.5% (3 of 26) incidence of respiratory depression in the patient-controlled analgesia-opioid group. Final arc range of motion was similar between postoperative axillary catheter infusion and patient-controlled analgesia-opioid groups. The data support the hypothesis that postoperative axillary catheter infusion provides better patient comfort and earlier postoperative continuous passive motion initiation, but they do not show additional improvement in the final arc of motion after distraction elbow arthroplasty as compared with a patient-controlled analgesia-opioid treatment group. 相似文献
70.
We have identified a novel RPGR gene mutation in a large Dutch family with X-linked retinitis pigmentosa (RP3). In affected members, a G-->T transversion was found at position +1 of the 5' splice site of intron 5 of the RPGR (retinitis pigmentosa GTPase regulator) gene. Analysis of this mutation at the RNA level showed cryptic splicing upstream of the mutation in exon 5 leading to a frameshift and downstream termination codon. Identification of the causative mutation in this family has facilitated the detection of females at risk of having an affected son. 相似文献