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1.
目的 评价调整光学切削直径及Kappa角后对准分子激光原位角膜磨镶术(laser in situ keratomileusis,LASIK)后效果的影响。方法 选取2017年1月至12月在我院行LASIK手术的高度近视患者313例(626眼),根据切削直径分成两组,试验组157例314眼,切削直径设定为6.0 mm,对照组156例312眼,切削直径设定为6.5 mm。试验组患者激光切削前修正Kappa角,对照组不做修正。患者术前进行裸眼视力、主视眼确定、验光、眼压、暗室下瞳孔直径、泪液分泌试验、裂隙灯、散瞳验光、眼底检查、pentacam测量角膜厚度、角膜地形图测量角膜前后表面及Kappa角等检查。术后1 d、1周、1个月随访,并检查裸眼视力、角膜厚度、波前像差及夜间视力、光晕、眩光等情况。比较两组患者角膜厚度变化、手术所用时间以及两组患者术后的高阶像差的差异。结果 试验组与对照组患者年龄分别为18~44(24.19±5.33)岁、18~42(25.08±4.91)岁,屈光度分别为(-7.47±1.04)D、(-7.61±1.12)D。两组年龄、屈光度比较差异均无统计学意义(均为P>0.05)。试验组与对照组患者术前Kappa角分别为,X轴:(210±40)μm、(200±30)μm,Y轴:(190±30)μm、(220±40)μm,差异无统计学意义(P=0.210)。两组手术前后的角膜厚度及术后角膜基质床的厚度差异均无统计学意义(均为P>0.05)。试验组与对照组的手术时间分别为(15.56±1.89)s和(20.83±3.03)s,差异有统计学意义(P=0.000)。试验组的总高阶像差和垂直慧差的变化均明显低于对照组(均为 P<0.01),但两组间的水平慧差差异无统计学意义(P>0.05),对照组的球差低于试验组(P<0.01)。结论 LASIK手术中科学合理地调整Kappa角可有助于提高患者术后的视觉质量。 相似文献
2.
Pulsed ultrasonic Doppler velocimetry (20 MHz) (PUDVM) has evolved considerably in the last 10 years. Engineering development has resulted in a computer-controlled vessel-scanning instrument whose backscattered frequency shift spectra are analyzed using fast Fourier transforms (FFT). Benchtop and theoretic studies indicate accurate (error less than 5%) velocity and volumetric flow rate measurements in vessels with a lumen diameter as small as 1.2 mm. Clinical application of the PUDVM has provided transcutaneous measurements of blood flow variables in normal human digital arteries. Experimental application to arteries 1.0-1.5 mm has provided information on the hemodynamic effects of topical vasodilators, standard microarteriorrhaphy, variations in microvascular technique, interpositional grafts, and early wound repair. With improving computer capabilities and technical modifications, the PUDVM will be an increasingly important tool in clinical and experimental microsurgery. 相似文献
3.
F. Bossa G. Cocomazzi M.R. Valvano A. Andriulli V. Annese 《Digestive and liver disease》2006,38(8):599-602
BACKGROUND AND STUDY AIM: Capsule endoscopy is a non-invasive technique for small bowel examination but its evaluation is time consuming. The aim of this study was to assess whether, following adequate training, an endoscopy nurse is capable of picking up all significant images without reducing the diagnostic accuracy of the procedure. PATIENTS AND METHODS: Between April 2003 and December 2004, a total of 41 consecutive capsule endoscopy studies were blindly reviewed by both an endoscopy nurse and an endoscopist. The two operators had to select all significant images independently and to complete a structured questionnaire. Thirty-nine capsule endoscopy examinations (two studies discharged for premature battery failure) were evaluated. The agreement between the two operators was calculated by kappa statistics (coefficient of agreement). RESULTS: Agreement was excellent for all kind of selected lesions (mean kappa>0.85); the agreement was complete (kappa=1) for site identification, active bleeding, stenosis and negative studies. The greater disagreement (kappa=0.77) was found in cases of subtle mucosal abnormalities (i.e. reduction of villi), which were over-estimated by the nurse. CONCLUSIONS: The preview recordings made by the nurse may increase the cost/effectiveness of the study, by considerably reducing the time needed for the endoscopist to make the final report (about 5-10 min), without compromising final diagnosis. 相似文献
4.
Intra-observer and inter-observer agreement of the manual examination of the lumbar spine in chronic low-back pain 总被引:1,自引:1,他引:0
Etienne Qvistgaard Jens Rasmussen Jes Lætgaard Steen Hecksher-Sørensen Henning Bliddal 《European spine journal》2007,16(2):277-282
Examination is a cornerstone in the manual procedures leading to mobilisation/manipulation of the low back. The observer variation of the more specific segmental tests remains to be investigated. Two skilled specialists in manual medicine examined the segmental changes in the lumbar spine. The patients were unknown to the examiners and no information of the case history was given. All test results were recorded by an observer present in the room who ensured that no conversation was allowed during the examination. The primary outcome measures were the kappa values for each test. The matching was defined as acceptable (acc) within two neighbouring levels and perfect (per) on the same level. Intra-observer variation (tested in 33 patients and 10 subjects without low-back pain): The agreement between first and second segmental diagnosis examination was 70% (per) and 82% (per + acc). Kappa values were: segmental diagnosis 0.60 (per) and 0.70 (per + acc), multifidus test 0.51 (per) and 0.60 (per + acc), sideflexion 0.57 (per) and 0.69 (per + acc), and ventral flexion 0.31 (per) and 0.45 (per + acc). Inter-observer variation (tested in 60 patients): The agreement for segmental diagnosis between the examiner A and B was 42% (per) and 75% (per + acc). Kappa values were: segmental diagnosis 0.21 (per) and 0.57 (acc), multifidus test 0.12 (per) and 0.48 (acc), sideflexion 0.22 (per) and 0.45 (acc), and ventralflexion 0.22 (per) and 0.44 (acc). By manual tests, skilled examiners seem to be able to diagnose segmental dysfunctions in the low back. The clinical implication of these dysfunctions remains to be clarified. 相似文献
5.
Autoradiographic localization of kappa opiate receptors in CNS taste and feeding areas 总被引:1,自引:0,他引:1
Recent evidence suggests that kappa opiate receptors may play a key role in the regulation of appetite. Such evidence implies that kappa receptors might be localized within specific brain areas known to regulate ingestive behaviors. On the basis of this implication we employed an in vitro film autoradiographic technique using 3H-ethylketocyclazozine as ligand to identify putative kappa receptors within CNS "taste" nuclei and surrounding areas. Coronal cryostat sections of rat brain were incubated with ligand in the presence of D-Ala2, D-Leu5-enkephalin (DADLE) and morphine, apposed to LKB Ultrofilm for 60 days, processed and kappa receptor densities evaluated with the aid of a hand held photometer and video image analyzer. Highest kappa receptor densities were found within various gustatory and feeding sites including the rostral pole of the nucleus of the solitary tract, parabrachial nuclei, ventral posterior and medial portions of the thalamus, medial hypothalamus, medial nuclei of the amygdala and bed nucleus of the stria terminalis. Various other midline and medial limbic areas also showed significant kappa densities. 相似文献
6.
作者自行设计的CSS-Ⅱ型心电图微型计算机自动诊断系统试用于临床,受试者1160例,其中波形异常和心律失常共247份心电图,从913份正常心电图中随机抽样106份,两者共计353份图纸,用本研究诊断确定的“金标准”(Gold standard)与该系统的自动诊断结论进行比较。结果:波形诊断及心律失常的诊断一致率均在90%以上,排除了机遇诊断一致率,其波形为90%,心律失常为88%。 相似文献
7.
In binding assays, both dynorphin B and alpha-neoendorphin are relatively selective for the kappa1b site, unlike U50,488H which has high affinity for both kappa1a and kappa1b sites. In vivo, U50,488H, dynorphin B and alpha-neoendorphin analgesia are reversed by the kappa1-selective antagonist, nor-binaltorphimine (norBNI). Antisense mapping the three exons of KOR-1 revealed that probes targeting all three exons blocked U50,488H analgesia, as expected. However, the selectivity profile of dynorphin B and alpha-neoendorphin analgesia towards the various antisense oligodeoxynucleotides differed markedly from U50,488H, implying a different receptor mechanism of action. 相似文献
8.
9.
《Annals of epidemiology》2014,24(4):246-253
PurposeMeasuring ethnicity accurately is important for identifying ethnicity variations in disease risk. We evaluated the degree of agreement and accuracy of maternal ethnicity measured using the new standardized closed-ended geographically based ethnicity question and geographic reclassification of open-ended ethnicity questions from the Canadian census.MethodsA prospectively designed study of respondent agreement of mothers of healthy children aged 1–5 years recruited through the TARGet Kids! practice-based research network. For the primary analysis, the degree of agreement between geographic reclassification of the Canadian census maternal ethnicity variables and the new geographically based closed-ended maternal ethnicity variable completed by the same respondent was evaluated using a kappa analysis.ResultsEight hundred sixty-two mothers who completed both measures of ethnicity were included in the analysis. The kappa agreement statistic for the two definitions of maternal ethnicity was 0.87 (95% confidence interval, 0.84–0.90) indicating good agreement. Overall accuracy of the measurement was 93%. Sensitivity and specificity ranged from 83% to 100% and 96% to 100%, respectively.ConclusionsThe new standardized closed-ended geographically based ethnicity question represents a practical alternative to widely used open-ended ethnicity questions. It may reduce risk of misinterpretation of ethnicity by respondents, simplify analysis, and improve the accuracy of ethnicity measurement. 相似文献
10.
Juan Ruiz Martín Consuelo Pérez Sánchez Alicia de las Heras Camino 《Pathology, research and practice》2013
In the early 21st century, a new way to classify breast cancer appeared, based on their gene expression profiles. Various classifications have been proposed in an attempt to subrogate these molecular groups to an immunohistochemical expression of estrogen and progesterone receptors, HER2 and Ki67. We compared the three major molecular classifications (MCs) of 374 infiltrating breast carcinomas with the assumption that one is better than the others to discriminate the prognosis of patients that are classified by it. We found that [1] there was a significant statistical association with tumor grade and presence of associated HG-DCIS, but with differences in kappa indices [2]; MC3 showed a significant relationship with pathological tumor stage (p = 0.012, CI95% of 0.012–0.017); [3] only MC3 showed convincingly that the observed differences in OS were not due to chance in the univariate analysis (p = 0.04); [4] only MC3 is an independent prognostic factor of OS. In conclusion, these three classifications are not interchangeable; MC3, the only one that includes Ki67 expression in their defining criteria, is better in predicting prognosis than the others. 相似文献