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81.
To determine whether polymorphisms of platelet surface glycoprotein associated with arterial thrombosis are risk factors for branch retinal vein occlusion. A case-control study in which 69 patients with branch retinal vein occlusion and 147 controls who attended the eye clinic for nonvascular complications participated. DNA was extracted from whole blood and analyzed for genotyping of platelet glycoprotein polymorphisms by polymerase chain reactions and specific restricted enzymes. No relationship was found between the four platelet glycoprotein polymorphisms i.e. GPIa C807T, VNTR and Kozak of glycoprotein Ibalpha, the HPA-1 of glycoprotein IIIa and the occurrence of branch retinal vein occlusion. The HPA-2 polymorphism was found in 18 out 60 (30%) patients with branch retinal vein occlusion in comparison with 27 out 142 (19%) of controls, with an estimated odds ratio of 1.8 (95% confidence interval, 0.91-3.65). The four platelet glycoprotein polymorphisms are not risk factors for branch retinal vein occlusion and therefore it seems unnecessary to screen those patients for it. A larger study is required, however, to determine whether HPA-2 is a novel risk factor for branch retinal vein occlusion.  相似文献   
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Using an earlier model, which described the critical contact angle for binding from second-order angulation alone, a more generalized model is derived that combines the effects of angulation and torque. From this vantage point, the onset of binding is evaluated for 3 scenarios: second-order angulation alone, third-order torque only, and a combination of second-order angulation and third-order torque. These scenarios are detailed by plotting the critical contact angle for binding against the torque angle as a function of 10 wire dimensions (16 x 16, 16 x 22, 17 x 17, 17 x 22, 17 x 25, 18 x 18, 18 x 22, 18 x 25, 19 x 25, and 21 x 25 mil), 4 bracket widths (70, 100, 130, and 160 mil), and 4 bracket slots (18, 20.5, 22, and 24.5 mil). From these plots, we learn that each wire base dimension (eg, an 18-mil base as found in 18 x 18-mil, 18 x 22-mil and 18 x 25-mil archwires) has a common maximum critical contact angle for binding. Moreover, each wire-slot combination has a common maximum torque angle, which is independent of bracket width. Finally, we learn that archwire-bracket combinations that use a metric 0.5-mm slot might have some advantages with regard to torquing--given the current philosophy that light, continuous forces are more favorable.  相似文献   
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BACKGROUND CONTEXT: The effectiveness of spinal surgery as a treatment option is currently evaluated through the assessment of patient-reported outcomes (PROs). The minimum clinically important difference (MCID) represents the smallest improvement considered worthwhile by a patient. The concept of an MCID is offered as the new standard for determining effectiveness of a given treatment and describing patient satisfaction in reference to that treatment. PURPOSE: Our goal is to review the various definitions of MCID and the methods available to determine MCID. STUDY DESIGN: The primary means of determining the MCID for a specific treatment are divided into anchor-based and distribution-based methods. Each method is further subdivided and examined in detail. METHODS: The overall limitations of the MCID concept are first identified. The basic assumptions, statistical biases, and shortcomings of each method are examined in detail. RESULTS: Each method of determining the MCID has specific shortcomings. Three general limitations in the accurate determination of an MCID have been identified: the multiplicity of MCID determinations, the loss of the patient's perspective, and the relationship between pretreatment baseline and posttreatment change scores. CONCLUSIONS: An ideal means of determining the MCID for a given intervention is yet to be determined. It is possible to develop a useful method provided that the assumptions and methodology are initially declared. Our efforts toward the establishment of a MCID will rely on the establishment of specific external criteria based on the symptoms of the patient and treatment intervention being evaluated.  相似文献   
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Cramer  J.  David  S.  Wich  M. 《Trauma und Berufskrankheit》2007,9(2):S220-S222
Trauma und Berufskrankheit - Nur 0,4–1% aller Frakturen betreffen die Skapula, die meisten davon können erfolgreich konservativ funktionell behandelt werden. Zur Identifikation der...  相似文献   
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Adult low-grade isthmic spondylolisthesis is often treated by posterolateral lumbar fusion (PLF), with a certain rate of complications and non-return to work. Alternatives to fusion, like pars defect repair (PDR), were used with encouraging results in young populations and athletes but their outcomes were rarely evaluated for adult patients. This retrospective study quantitatively analysed the long-term outcomes in adult isthmic spondylolisthesis patients treated by PLF or PDR. At a mean follow-up of 9 years, clinical, socio-professional, radiological data and Stauffer-Coventry score were available for 59 patients (39 cases treated by PLF and 20 treated by PDR). The overall clinical outcomes were comparable in both populations (88% in the PDR and 80% in PLF group 1), with a larger proportion of excellent results (56% vs. 10%) and of return to work in the PDR group. Radiological quantitative analysis highlighted stationary evolution and comparable outcomes for the two groups, except for vertebral slip evolution and adjacent level degeneration rate. Abnormal kinematic patterns outlined for PLF patients 20% of pseudarthrosis and 42% of adjacent levels hypermobility and for PDR ones low mobility for the levels adjacent to instrumented vertebra in 40% of cases. Quantified analysis of biomechanical parameters interpreted altogether with clinical outcome, complications and economic burden of the patient, provided accurate objective data for a better appreciation of global outcome, allowing for a preliminary view on long-term outcomes after PDR in adult low-grade isthmic spondylolisthesis, which were not presented in literature until now.  相似文献   
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Objectives: Heavy smokers are a segment of the smoking population who are at increased risk of smoking-related morbidity and least likely to achieve cessation. This study identifies the impact of heavy smoking on quality of life by gender and describes the subpopulation for improved targeting.Methods: South Australian representative population data (n = 3010) was used to compare the health-related quality of life status of male and female heavy smokers as assessed by the SF-36.  相似文献   
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