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91.
92.
Unusual eustachian tube mass: glomus tympanicum 总被引:1,自引:0,他引:1
Lum C Keller AM Kassel E Blend R Waldron J Rutka J 《AJNR. American journal of neuroradiology》2001,22(3):508-509
SUMMARY: A case of recurrent glomus tympanicum presenting with epistaxis is described. CT and MR imaging revealed a homogeneously enhancing mass extending along the entire course of the eustachian tube, with a portion protruding into the nasopharynx. Glomus tumors tend to spread along the path of least resistance and may extend into the eustachian tube. The unique imaging appearance should place a glomus tumor high on the list of differential diagnoses. 相似文献
93.
94.
Triggle CR Dong H Waldron GJ Cole WC 《Clinical and experimental pharmacology & physiology》1999,26(2):176-179
1. Endothelium-derived relaxing factor is almost universally considered to be synonymous with nitric oxide (NO); however, it is now well established that at least two other chemically distinct species (prostacyclin (PGI2) and a hyperpolarizing factor) may also contribute to endothelium-dependent relaxation. 2. Only relatively few studies have provided definitive evidence that an endothelium-derived hyperpolarizing factor (EDHF), which is neither NO nor PGI2, exists as a chemical mediator. 3. There is a lack of agreement as to the likely chemical identity of this putative factor. Some evidence suggests that EDHF may be a cytochrome P450-derived arachidonic acid product, possibly an epoxyeicosatrienoic acid (EET); conflicting evidence supports an endogenous cannabinoid as the mediator and still other studies infer an unknown mediator that is neither a cytochrome P450 nor a cannabinoid. 4. Data from our laboratory with a rabbit carotid artery 'sandwich' preparation have provided evidence that a mediator that meets the pharmacological expectations of a cytochrome P450 product is an EDHF. 5. Data from guinea-pig mesenteric arterioles suggest that EDHF is not a cytochrome P450 product, whereas in guinea-pig middle cerebral arteries, relaxation mediated by the NO/PGI2-independent mediator(s) is sensitive to cytochrome P450 inhibitors. In addition, in the rabbit middle cerebral artery, it is likely that endothelium-dependent hyperpolarization is mediated by both NO and PGI2. 6. In conclusion, these data indicate that EDHF is unlikely to be a single factor and that considerable tissue and species differences exist for the nature and cellular targets of the hyperpolarizing factors. 相似文献
95.
筛窦癌发病率低,就诊时病期晚,5年无瘤生存率为30%~50%。由于解剖部位的限制以及局部浸润,放射和手术均有一定难度。作者回顾性分析皇家Margret医院1976~1994年收治的29例浸润性筛窦癌根治性放射治疗的疗效和影响预后因素。男性24例,女性4例,中位年龄62岁,中位随访时间4年。常有鼻出血、鼻塞、疼痛及视力改变等。起病到确诊的平均时间为9个月。27例吸烟,10例从事伐木或镍的开采与提炼。 治疗前均经临床及影像学检查。仅3例局限于筛窦,余侵犯鼻腔、蝶窦、眼眶、上颌窦、额窦及脑内等。T1… 相似文献
96.
Ultrasound‐guided percutaneous tenotomy for the treatment of iliopsoas impingement: A description of technique and case study 下载免费PDF全文
Matthew J Sampson Nimah Rezaian James MK Hopkins 《Journal of Medical Imaging and Radiation Oncology》2015,59(2):195-199
Iliopsoas impingement is a commonly recognised source of groin pain following total hip replacement. When conservative measures fail, open or arthroscopic iliopsoas tendon release can reliably alleviate pain and improve function. This article describes an alternative ultrasound‐guided percutaneous technique, achieving iliopsoas tenotomy utilising a modified 18G coaxial needle and thus minimising the morbidity and cost associated with an open or arthroscopic procedure. This method proved successful with resultant complete resolution of patient symptoms. To the knowledge of the authors, this is the first case of ultrasound‐guided percutaneous iliopsoas tenotomy for iliopsoas impingement post total hip replacement. 相似文献
97.
Kaufman PE Harrington LC Waldron JK Rutz DA 《Journal of the American Mosquito Control Association》2005,21(2):171-176
The presence of mosquito species breeding in agricultural "bunker tires" on dairy farms in New York state was evaluated. Twelve species of mosquitoes (Aedes vexans, Anopheles barberi, An. punctipenriis, An. perplexens, Culex pipiens pipiens, Cx. restuans, Cx. salinarius, Cx. territans, Toxorhynchites rutilus septentrionalis, Ochlerotatus atropalpus, Oc. japonicus japonicus, and Oc. triseriatus) were collected from 8 New York state dairy farms in 2001 and from 17 dairy farms in 2002. All but 2 of these species have been found naturally infected with arboviruses and could be important vectors affecting human and animal health. Because of the potential public and animal health importance of the invasive species Oc. j. japonicus, active surveillance to identify breeding sites and distribution of this mosquito is essential. In 2001, Oc. j. japonicus was recovered from 5 of 8 central New York dairy farms surveyed. In 2002, Oc. j. japonicus was recovered from 4 of the same dairy farms plus an additional dairy out of 5 surveyed. This species appears to be established on dairy farms in the south, central, and eastern regions of New York state, with greatest abundance in the southeastern region. A single Oc. j. japonicus larva was collected from the northern region on the final sampling date in September 2002. Our data demonstrate that agricultural tire habitats can be productive breeding sites for arbovirus vectors. As a consequence, these habitats should not be ignored in vector control and surveillance programs. 相似文献
98.
99.
Distribution of mutations in the PEX gene in families with X-linked hypophosphataemic rickets (HYP) 总被引:8,自引:0,他引:8
Rowe PS; Oudet CL; Francis F; Sinding C; Pannetier S; Econs MJ; Strom TM; Meitinger T; Garabedian M; David A; Macher MA; Questiaux E; Popowska E; Pronicka E; Read AP; Mokrzycki A; Glorieux FH; Drezner MK; Hanauer A; Lehrach H; Goulding JN; O'Riordan JL 《Human molecular genetics》1997,6(4):539-549
Mutations in the PEX gene at Xp22.1 (phosphate-regulating gene with
homologies to endopeptidases, on the X-chromosome), are responsible for
X-linked hypophosphataemic rickets (HYP). Homology of PEX to the M13 family
of Zn2+ metallopeptidases which include neprilysin (NEP) as prototype, has
raised important questions regarding PEX function at the molecular level.
The aim of this study was to analyse 99 HYP families for PEX gene
mutations, and to correlate predicted changes in the protein structure with
Zn2+ metallopeptidase gene function. Primers flanking 22 characterised
exons were used to amplify DNA by PCR, and SSCP was then used to screen for
mutations. Deletions, insertions, nonsense mutations, stop codons and
splice mutations occurred in 83% of families screened for in all 22 exons,
and 51% of a separate set of families screened in 17 PEX gene exons.
Missense mutations in four regions of the gene were informative regarding
function, with one mutation in the Zn2+-binding site predicted to alter
substrate enzyme interaction and catalysis. Computer analysis of the
remaining mutations predicted changes in secondary structure,
N-glycosylation, protein phosphorylation and catalytic site molecular
structure. The wide range of mutations that align with regions required for
protease activity in NEP suggests that PEX also functions as a protease,
and may act by processing factor(s) involved in bone mineral metabolism.
相似文献
100.
Speech-controlled generation of radiology reports 总被引:1,自引:0,他引:1
Robbins AH; Horowitz DM; Srinivasan MK; Vincent ME; Shaffer K; Sadowsky NL; Sonnenfeld M 《Radiology》1987,164(2):569-573
Voice entry has been successfully employed to generate radiology reports with a word recognizer with a 1,000-word lexicon capacity. About 50% of reports were able to be dictated with a single 900-word lexicon. This was split into five sections by anatomic or subspecialty application. Each was augmented to 900 words. By switching from one lexicon to another, it was possible to dictate more than 70% of reports. With exclusive use of three lexicons in subspecialty areas (gastrointestinal radiology, neuroradiology, and mammography), and with further modification of the respective vocabulary, it has been possible to employ the system 88% of the time. Twelve percent of cases included wording that was beyond the scope of the lexicon. Computer subsets that allow different translations of some words when used in different contexts have been used. Some of these are used as triggers that will print whole lines, sentences, or even complete reports. Dictation times with voice entry take about 20% longer. Recognition reliability has been greater than 95%. 相似文献