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1.
Artifacts in spectral and color Doppler imaging can be confusing and lead to misinterpretation of flow information. The authors review these artifacts by considering three main causes: inappropriate equipment settings, anatomic factors, and physical and technical limitations of the modality. Incorrect gain, wall-filter, or velocity scale settings can cause loss of clinically important information or distortion of the tracing. Reflection of the Doppler signal from highly reflective surfaces can create a color Doppler mirror image. Vascular motion can introduce artifactual variation in velocity as the sample volume passes through different velocities in a laminar flow state. Unintentional motion can cause a generalized Doppler shift. Increasing the angle of Doppler interrogation degrades the quality of the tracing and gives the impression of spectral broadening. As angulation approaches 90 degrees, directional ambiguity can occur, suggesting bidirectional flow. Grating and side lobes can interrogate areas unrelated to the sample volume and introduce extraneous Doppler information to the apparent area of interrogation. Recognition of these artifacts is essential to proper interpretation of Doppler information and rendering a correct diagnosis. 相似文献
2.
GP SCHWAB AL BLUM E BODNER B DALLEMAGNE K GLASER H KOOP F PACE W RÖSCH JR SIEWERT G WETSCHER 《Journal of gastroenterology and hepatology》1997,12(12):785-789
Gastroesophageal reflux disease (GERD) is the most common disease of the upper gastrointestinal tract. With the introduction of proton pump inhibitors medical treatment of GERD has been significantly improved. However, the development of laparoscopic antireflux surgery resulted in an increasing interest of surgeons in this disease. An interactive meeting was organized in order to develop an agreement between gastoenterologists and surgeons regarding therapeutic decisions and this is the main topic of this paper. 相似文献
3.
Popliteal entrapment as a result of neurovascular compression by the soleus and plantaris muscles. 总被引:4,自引:0,他引:4
Intermittent claudication may occur in well-conditioned athletes because of an unusual form of popliteal artery entrapment that results from overtraining. These patients complain of calf muscle cramping, rapid limb fatigue, and occasional paresthesias on the plantar surface of the foot when running on inclines or when repetitive jumping is performed. Results of plethysmographic screening tests for popliteal entrapment are positive in these patients. Magnetic resonance angiography and intravenous digital subtraction angiography studies, however, do not demonstrate findings typical of anatomic popliteal entrapment. No evidence exists of aberrant positioning of the popliteal artery in foot neutral positioning, but with forced plantar flexion, the neurovascular bundle is deviated and compressed laterally. Surgical exploration of the popliteal fossa demonstrates no obvious musculotendinous abnormality. Symptoms of claudication and arterial compression are relieved by surgical release of the soleus muscle from its tibial attachments, resection of its fascial band, and resection of the plantaris muscle. 相似文献
4.
5.
E J Beck K Tolley A Power S Mandalia P Rutter J Izumi J Beecham A Gray D Barlow P Easterbrook M Fisher J Innes G Kinghorn B Mandel A Pozniak A Tang D Tomlinson I Williams 《PharmacoEconomics》1998,14(6):639-652
OBJECTIVE: The aim of the study was to measure the use and estimate the cost of HIV service provision in England. DESIGN AND SETTING: Standardised activity and case-severity data were collected prospectively in 10 English HIV clinics (5 London and 5 non-London sites) for the periods 1 January 1996 to 30 June 1996 and 1 July 1996 to 31 December 1996 and linked to unit cost data. In total, 5440 patients with HIV infection attended during the first 6 months and 5708 during the second 6 months in 1996. MAIN OUTCOME MEASURES AND RESULTS: The mean number of inpatient days per patient-year for patients with AIDS was 19.7 [95% confidence interval (CI): 13.7 to 25.7] for January to June and 20.8 (95% CI: 15.3 to 26.4) for July to December 1996. The mean number of outpatient visits for asymptomatic patients with HIV infection was 14.8 (95% CI: 11.9 to 17.6) and 13.3 (95% CI: 10.8 to 15.7) for the respective periods and 16.1 (95% CI: 13.21 to 18.97) and 15.7 (95% CI: 11.2 to 20.2), respectively, for patients with symptomatic non-AIDS (i.e. symptomatic patients with HIV infection but without AIDS-defining conditions). Substantial centre-to-centre variation was observed, suggesting that many clinics can continue the shift from an inpatient- to an outpatient-based service. Cost estimates per patient-year for HIV service provision for 1996 varied from 4695 Pounds (95% CI: 3769 Pounds to 5648 Pounds) for asymptomatic patients, to 7605 Pounds (95% CI: 6273 Pounds to 8909 Pounds) for symptomatic non-AIDS patients to 20,358 Pounds (95% CI: 17,681 Pounds to 23,206 Pounds) for patients with AIDS. CONCLUSIONS: Different combinations of antiretroviral therapy affect the cost estimates of HIV service provision differently. Anticipated reduction in inpatient-related activity through the increased use of combination antiretroviral therapy will further shift service provision from an inpatient- to outpatient-based service and reduce costs per patient-year. The extent and duration of such effects are currently unknown. The long term effects of combination treatment on the morbidity and mortality patterns of individuals infected with HIV are also currently unknown, as are their implications on the use and cost of HIV service provision. Multicentre databases like the National Prospective Monitoring System (NPMS) will provide healthcare professionals with information to improve existing services and anticipate the impact of new developments. 相似文献
6.
Missense FGFR3 mutations create cysteine residues in thanatophoric dwarfism type I (TD1) 总被引:10,自引:1,他引:10
Rousseau F; el Ghouzzi V; Delezoide AL; Legeai-Mallet L; Le Merrer M; Munnich A; Bonaventure J 《Human molecular genetics》1996,5(4):509-512
Thanatophoric dwarfism (TD) is a sporadic lethal skeletal dysplasia with
micromelic shortening of the limbs, macrocephaly, platyspondyly and reduced
thoracic cavity. In the most common subtype (TD1), femurs are curved, while
in TD2, straight femurs are associated with cloverleaf skull. Mutations in
the fibroblast growth factor receptor 3 (FGFR3) gene were identified in
both subtypes. While TD2 was accounted for by a single recurrent mutation
in the tyrosine kinase 2 domain, TD1 resulted from either stop codon
mutations or missense mutations in the extracellular domain of the gene.
Here, we report the identification of FGFR3 mutations in 25/26 TD cases.
Two novel missense mutations (Y373C and G370C) were detected in 8/26 and
1/26 TD1 cases respectively. Both mutations created cysteine residues in
the juxta extramembrane domain of the receptor. Sixteen cases carried the
previously reported R248C (9/26 cases), S249C (2/26 cases) or stop codon
FGFR3 mutations (5/26 cases). Our results suggest that TD1 is a genetically
homogeneous condition and give additional support to the view that newly
created cysteine residues in the extracellular domain of the protein play a
key role in the severity of the disease.
相似文献
7.
8.
9.
Identification of the multiple endocrine neoplasia type 1 (MEN1) gene. The European Consortium on MEN1 总被引:10,自引:0,他引:10
Lemmens I; Van de Ven WJ; Kas K; Zhang CX; Giraud S; Wautot V; Buisson N; De Witte K; Salandre J; Lenoir G; Pugeat M; Calender A; Parente F; Quincey D; Gaudray P; De Wit MJ; Lips CJ; Hoppener JW; Khodaei S; Grant AL; Weber G; Kytola S; Teh BT; Farnebo F; Thakker RV 《Human molecular genetics》1997,6(7):1177-1183
10.
Yang GC; Croaker D; Zhang AL; Manglick P; Cartmill T; Cass D 《Human molecular genetics》1998,7(6):1047-1052
Lethal white foal syndrome (LWFS) is a congenital anomaly of horses
characterized by a white coat colour and aganglionosis of the bowel, which
is similar to Hirschsprung disease (HSCR). We decided to investigate
possible mutations of the endothelin-B receptor gene ( EDNRB ) in LWFS as
recent studies in mutant rodents and some patients have demonstrated EDNRB
defects. First, we identified a full-length cDNA for horse EDNRB . This
cDNA fragment contained a 1329 bp open reading frame which encoded 443
amino acid residues. The predicted amino acid sequence was 89, 91 and 85%
identical to human, bovine and mouse as well as rat EDNRB respectively, but
only 55% identical to the human, bovine and rat endothelin A receptor
(EDNRA). Secondly, sequence analysis, together with allele-specific PCR and
the amplification- created restriction site (ACRS) technique, revealed a
dinucleotide TC-- >AG mutation, which changed isoleucine to lysine in
the predicted first transmembrane domain of the EDNRB protein. This was
associated with LWFS when homozygous and with the overo phenotype when
heterozygous.
相似文献