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511.
A new aging method, fluorescent observation of burnt otoliths, was discovered to disclose the age and growth of the conger eel. Under UV light, bright fluorescent zones were visible in the burnt otolith but not in the unburnt otolith. An illumination wavelength around 380 nm was found to be suitable for fluorescence observation of burnt otoliths. Bright zones of the conger eel otolith formed around June–August in Sendai Bay and were validated as annuli. The conger eels caught by net pot fishery were found to be mainly aged from 1+ to 4+ years. Received: March 7, 2001 / Revised: September 12, 2001 / Accepted: October 10, 2001  相似文献   
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This article examines how scientists move from physical measurementsto actual observation of single-cell recordings in the brain. We highlight how easy it is to change the fundamental nature of ourobservations using accepted methodological techniques for manipulatingraw data. Collecting single-cell data is thoroughly pragmatic. Weconclude that there is no deep or interesting difference betweenaccounting for observations by measurements and accounting forobservations by theories.  相似文献   
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ObjectiveActive surveillance (AS) has been shown to be a safe approach that can effectively block transition from overdiagnosis to overtreatment in patients with low-risk papillary thyroid microcarcinoma (PTMC). This study aimed to determine whether the AS approach can be implemented in China and investigate the population characteristics of Chinese patients who underwent AS.MethodsThe epidemiologic and clinical characteristics as well as patient adherence were evaluated in 115 patients who underwent AS management as an alternative to immediate surgery for low-risk (or highly suspected) PTMC.ResultsThe mean patient age was 41.8 ± 10.3 years, with 41.7% and 4.4% of the patients aged <40 and ≥60 years, respectively. The median baseline diameter of index tumors was 4 (range, 3-6) mm, with 73.0% of the tumors being ≤5 mm. A total of 84.4% of the patients had a junior college, college, or graduate degree, and 83.5% were employed by the government, public institutions, companies, or technical posts. After a median 25-month follow-up, a tumor growth of ≥3 mm occurred in 3 patients (2.6%), and no new lymph node metastasis occurred. Surgery was performed in 4 patients because of patient preferences rather than because of disease progression. There was satisfactory adherence in 109 patients (94.8%) in a simulated ideal medical environment.ConclusionThe AS approach can be used as an alternative to low-risk PTMC management in China. Given the difference in epidemiologic and clinical characteristics, Chinese institutions should fully consider the features of the Chinese population while developing candidate criteria, surveillance intervals, and follow-up strategies for AS.  相似文献   
515.
Influence diagnostics for linear measurement error models   总被引:1,自引:0,他引:1  
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At a natural drone congregation area freeflying drones were attracted by a fast-moving queen dummy and the pursuits of drones were stereoscopically recorded (Fig. 1). The reconstruction of 192 flight paths from successfully approaching drones in chronological three dimensional sequences (Fig. 4) lead to the following results: 1. The alignment of the drone's longitudinal body axis coincides fairly well with the line connecting drone and queen (drone-queen-axis), its mean angular deviation from this line being only 14°. Angles between -5° and 5° occur most frequently (Fig. 5B). Thus, drones head straight to the queen. 2. Lateral deviations from the drone-queen-axis most frequently lie between — 30° and 30° (Fig. 5A) which corresponds to the drone's binocular visual field. 3. The drone's heading was continuously adjusted to the actual target, mean turning speed being 1890°/s. 4. The results lead to the conclusion that honeybee drones choose the shortest way to a fast and not predictably moving mate. A comparison with earlier observations suggests that a drone's mating success depends not only on his skills to win a race but also on his persistence within a group.  相似文献   
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摘要 目的:探究阿扎胞苷(Azacitidine,AZA)单药或联合HAG方案治疗骨髓增生异常综合征(Myelodysplastic syndromes,MDS)的临床疗效及安全性。方法:回顾性分析49例MDS患者的临床资料,根据治疗方法不同分为支持治疗组和含AZA组(单药或联合HAG方案),统计分析患者的临床疗效及不良反应情况。结果:支持治疗组的总有效率(Overall response rate,ORR)为30.00 %(6/20),包括0例完全缓解(Complete remission,CR),1例骨髓完全缓解(Marrow complete remission,mCR),2例部分缓解(Partial remission,PR), 3例血液学改善(Hematological improvement,HI)。含AZA组的ORR为65.52 %,包括8例CR、2例mCR、4例PR、5例HI。其中单药组的ORR为46.67 %, 包括2例CR、1例mCR、2例PR、2例HI;联合组的ORR为85.71 %,包括6例CR、1例mCR、2例PR、3例HI。与支持治疗组相比,含AZA组的完全缓解率(CR+mCR)及ORR显著增高,差异有统计学意义(P<0.05)。患者最常见的不良反应是III-IV级骨髓抑制(18/29)及继发感染(10/29),且随着疗程数的增加不良事件逐渐减少。含AZA组患者的中位总生存(Overall survival,OS)时间及中位无进展生存时间(Progression-free survival,PFS)时间显著延长(P<0.05)。结论:该小系列研究的初步结果表明,与支持治疗相比,AZA单药或联合HAG方案治疗MDS有更高的治疗反应,可延长患者总生存期,患者有良好的耐受性,且联合治疗方案可能有更好的疗效。  相似文献   
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