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71.
Petra Mullner Simon E.F. Spencer Daniel J. Wilson Geoff Jones Alasdair D. Noble Anne C. Midwinter Julie M. Collins-Emerson Philip Carter Steve Hathaway Nigel P. French 《Infection, genetics and evolution》2009,9(6):1311-1319
Integrated surveillance of infectious multi-source diseases using a combination of epidemiology, ecology, genetics and evolution can provide a valuable risk-based approach for the control of important human pathogens. This includes a better understanding of transmission routes and the impact of human activities on the emergence of zoonoses. Until recently New Zealand had extraordinarily high and increasing rates of notified human campylobacteriosis, and our limited understanding of the source of these infections was hindering efforts to control this disease. Genetic and epidemiological modeling of a 3-year dataset comprising multilocus sequence typed isolates from human clinical cases, coupled with concurrent data on food and environmental sources, enabled us to estimate the relative importance of different sources of human disease. Our studies provided evidence that poultry was the leading cause of human campylobacteriosis in New Zealand, causing an estimated 58–76% of cases with widely varying contributions by individual poultry suppliers. These findings influenced national policy and, after the implementation of poultry industry-specific interventions, a dramatic decline in human notified cases was observed in 2008. The comparative-modeling and molecular sentinel surveillance approach proposed in this study provides new opportunities for the management of zoonotic diseases. 相似文献
72.
Steve Ramcharitar Mark S Patterson Robert J van Geuns Martin van der Ent Georgios Sianos Gijs M J M Welten Ron T van Domburg Patrick W Serruys 《Catheterization and cardiovascular interventions》2007,70(5):662-668
OBJECTIVES: To directly compare the magnetic navigation system (MNS) guidewires with conventional guidewires in branching tortuous phantoms with operators of varying MNS and percutaneous coronary intervention experience. BACKGROUND: Vessel tortuosity, angulation, and side branches remain limiting factors in coronary interventions. The MNS addresses these limitations by precisely directing the tip of a magnetised guidewire in vivo aided by two permanent adjustable external magnets. METHODS: Crossing and fluoroscopy times of six operators were evaluated in five tortuous Perspex(R) phantom vessels in three consecutive attempts. Standard guidewire (SG) usage was unrestricted. Two 2nd generation magnetic guidewires (MG) were used. Failure was noted if the cross was unsuccessful within 5 min. RESULTS: The magnetic navigation was vastly superior to SG techniques with increasingly tortuous phantoms. It dramatically decreased both the crossing and fluoroscopy times with maximal reduction from 201.7 +/- 111 to 36.4 +/- 13 sec, P < 0.001 and 204.7 +/- 24 to 47.2 +/- 19 sec, P < 0.001, respectively. The MNS had a 98.8% procedural success rate compared to 68% with SG techniques. Moreover it considerably limited the amount of wire usage from 5.5 to 1.3. Operators with prior MG experience performed significantly better than those without, except in the simplest phantom where the difference was nonsignificant (33.8 +/- 13 sec vs. 41.7 +/- 17 sec, P = 0.2). CONCLUSION: MNS significantly reduces both the crossing and fluoroscopy times in tortuous coronary phantom models achieving excellent success rates with dramatic reductions in guidewire usage. Operators with prior MNS experience had an advantage over the inexperienced. 相似文献
73.
Adam M Alessio Steve Kohlmyer Kelley Branch Grace Chen James Caldwell Paul Kinahan 《Journal of nuclear medicine》2007,48(5):794-801
In dual-modality PET/CT systems, the CT scan provides the attenuation map for PET attenuation correction. The current clinical practice of obtaining a single helical CT scan provides only a snapshot of the respiratory cycle, whereas PET occurs over multiple respiratory cycles. Misalignment of the attenuation map and emission image because of respiratory motion causes errors in the attenuation correction factors and artifacts in the attenuation-corrected PET image. To rectify this problem, we evaluated the use of cine CT, which acquires multiple low-dose CT images during a respiratory cycle. We evaluated the average and the intensity-maximum image of cine CT for cardiac PET attenuation correction. METHODS: Cine CT data and cardiac PET data were acquired from a cardiac phantom and from multiple patient studies. The conventional helical CT, cine CT, and PET data of an axially translating phantom were evaluated with and without respiratory motion. For the patient studies, we acquired 2 cine CT studies for each PET acquisition in a rest-stress (13)N-ammonia protocol. Three readers visually evaluated the alignment of 74 attenuation image sets versus the corresponding emission image and determined whether the alignment provided acceptable or unacceptable attenuation-corrected PET images. RESULTS: In the phantom study, the attenuation correction from helical CT caused a major artifactual defect in the lateral wall on the PET image. The attenuation correction from the average and from the intensity-maximum cine CT images reduced the defect by 20% and 60%, respectively. In the patient studies, 77% of the cases using the average of the cine CT images had acceptable alignment and 88% of the cases using the intensity maximum of the cine CT images had acceptable alignment. CONCLUSION: Cine CT offers an alternative to helical CT for compensating for respiratory motion in the attenuation correction of cardiac PET studies. Phantom studies suggest that the average and the intensity maximum of the cine CT images can reduce potential respiration-induced misalignment errors in attenuation correction. Patient studies reveal that cine CT provides acceptable alignment in most cases and suggest that the intensity-maximum cine image offers a more robust alternative to the average cine image. 相似文献
74.
BACKGROUND: Acne vulgaris is an acute inflammatory disease of the pilosebaceous units. The bastion of treatment for acne vulgaris has been the use of topical and systemic therapies. Despite many modalities available for treatment, there exists an imperative need for effective noninvasive treatments that reduce the risks of medication side effects. OBJECTIVE: To study the safety and efficacy of the potassium titanyl phosphate (KTP) 532 nm pulsed laser for the treatment of acne vulgaris. METHODS: Twenty-six subjects, clinically evaluated with moderate facial acne, were enrolled in this single-center prospective trial. The entire facial area for each subject was divided in half and randomly designated as either a treatment or a control side. Each subject was treated with four laser exposures using a KTP 532 nm laser with continuous contact cooling. The results were assessed at 1 and 4 weeks post-final treatment. Primary outcome measures were Micha?lsson acne severity score and adverse treatment effects. Secondary outcome measures included subjective evaluations from the investigator and patients assessing their overall percent satisfaction. RESULTS: Primary outcome analysis in the Micha?lsson acne severity score demonstrated a mean 34.9% (p = .011) and 20.7% (p = .25) reduction at the 1-week and 4-week post-final treatments, respectively. Subjective investigator evaluations of overall percent satisfaction indicated that all patients demonstrated a minimum 50% overall satisfaction in treatment outcomes at the 4-week follow-up period. No side effects were encountered. CONCLUSION: Use of the KTP 532 nm laser for the treatment and management of acne vulgaris is both safe and effective, with positive results enduring up to 4 weeks post-treatment. 相似文献
75.
Hemovigilance for improvement of blood safety. 总被引:2,自引:0,他引:2
76.
77.
78.
Jose A. Acosta MD Joseph A. Greenlee MD K. Dean Gubler DO Cary J. Goepfert MD Jerry J. Ragland MD 《American journal of surgery》1995,170(6)
: The use of needle-localization breast biopsy (NLBB) for the early diagnosis of breast cancer is common. The therapeutic adequacy of tumor-free margins following NLBB is unknown. We hypothesized that the presence of residual tumor after reexcision (mastectomy, tylectomy, or quadrantectomy) does not depend on the margin status following NLBB.
: Retrospective cohort analysis was performed on 890 consecutive NLBBs executed between January 1990 and June 1994. Patients with invasive breast neoplasia were divided into two groups based on the tumor margins after NLBB. Group 1 were the women with positive margins, and group 2 had negative margins. Breast specimens after reexcision were reviewed for evidence of residual invasive carcinoma.
: Invasive neoplasia was present in 107 patients (12%). Surgical margins and definitive records of care were avaliable for 96 of them (90%). All 45 patients in group 1 and 38 (75%) of 51 patients in group 2 underwent reexcision of the initial biopsy site (P = 0.36). Residual invasive carcinoma was present in 10 patients (22%) in group 1 and 3 (8%) in group 2 (P = 0.13).
: Invasive breast neoplasia diagnosed by NLBB requires reexcision regardless of tumor margins to achieve complete local surgical eradication of tumor. 相似文献
79.
80.
Mirjam Gross-Jendroska Christina J Flaxel Steve D Schwartz Frank G Holz Fred W Fitzke Veit-Peter Gabel Alan C Bird 《Clinical & experimental ophthalmology》1998,26(4):311-317
Purpose: To flatten pigment epithelial detachments (PED) cue to age-related macular degeneration in an attempt to visualize the underlying choroidal neovascularization by fluorescein angiography (FA) and reveal a treatment target. Methods: Nine patients with PED received intravitreal gas injections via the pars plana and postured face down. Fluorescein angiograms were obtained before and after gas injection. In two patients, retinal scotopic sensitivity was also measured. Results: Eight patients demonstrated change in the shape and size of the PED following gas injection. Four patients showed a better delineation of underlying structures on FA. Three patients had focal laser treatment to the newly visible choroidal neovascular complex, but this was successful in only one patient with flattening of the PED. Conclusion: Pigment epithelial detachments can be modified by intravitreal gas injection in some patients, but this treatment did not have a major impact on overall outcome or management. 相似文献