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91.
Color is one of the factors used in quality estimation in many agricultural and food products. Currently, the evaluation of color depends on judgments made by human experts. These are subjective and inevitably affected by physical, physiological and environmental conditions. Suitable instrumental is required to provide objectivity and coherence to color measurements and quantitative expressions. It would be very useful to have tools that allow both practical and precise approaches to chromatic evaluation of products for human consumption. This work suggests a methodology which might contribute to solve that constraint and the analysis of environmental influences on this character in two consecutive wheat growing seasons. This research used 18 cultivars, which were sampled in two crop growth stages. On the first part of this study, a spectrophotometer and a digital camera were used for the analysis of color at the phenological state of tillering. Data analysis showed a correlation between both study methodologies, which would make more practical the work of breeders during data collection. The second part of the study of the genotype-environment interaction (GEI) continued using only a digital camera. The phenological state of tillering did not evidence a marked GEI. On the other hand, an appreciable GEI was found at physiological ripeness. 相似文献
92.
Canopy structure in a temperate old-growth evergreen forest analyzed by using aerial photographs 总被引:2,自引:0,他引:2
We used aerial photographs to create a digital elevation model of the canopy surface of a 10-ha study area in a temperate old-growth evergreen forest. A topographic map of the ground surface in a 4-ha permanent plot within the study area was also drawn from ground measurements. The difference between the two elevation values (i.e., canopy surface – ground surface) at each point in a 5-m grid was considered to be the canopy height, and a canopy height profile was constructed from these data. The canopy structure in the 4-ha plot that was estimated in this way was compared with that obtained by two ground observation methods, i.e., the canopy (vegetation) height profile method and the canopy coverage census method. Large gaps were adequately detected by the aerial photograph method, but small gaps were less often detected. Gap size distribution obtained by the aerial photograph method was similar to that observed on the ground, and was a function of gap depth. This study indicates that if a detailed topographic map can be made, the canopy height profile derived from aerial photography can be effective in analyzing the canopy structure of evergreen forests, such as tropical rain forests, over large areas. 相似文献
93.
94.
目的:探讨颅内静脉系统血栓形成(CVT)的临床表现、影像学特征以及治疗方法对临床诊断的意义。方法:回顾性分析首都医科大学宣武医院收治的6例CVT患者的临床表现及影像学特征与治疗方法。结果:6例临床表现无特殊,4例经MRI+MRV确诊,3例DSA检查确诊,1例介入治疗,4例抗凝治疗,2例保守,无死亡患者。结论:静脉系统血栓形成临床症状缺乏特异性,临床遇到急性起病的头痛、呕吐,伴或不伴有局灶性神经功能缺损或癫痫发作、意识障碍的青中年人,应高度怀疑CVT。早期应用抗凝、溶栓等治疗方法,对改善预后具有较高的临床应用价值。 相似文献
95.
96.
摘要 目的:探讨数字减影血管造影(DSA)引导下肝动脉化疗栓塞(TACE)对肝癌患者肝功能、细胞免疫功能及肿瘤标志物的影响。方法:随机选取2021年1月~2022年1月来我院就诊的行DSA引导下TACE化疗的肝癌患者50例为研究组,另随机选取同期行常规治疗的肝癌患者50例为对照组,对比两组临床总有效率、肝功能、细胞免疫功能及肿瘤标志物和不良反应情况。结果:研究组的临床总有效率为56.00%(28/50)高于对照组的34.00%(17/50),差异有统计学意义(P<0.05)。两组治疗结束后谷草转氨酶(AST)和谷丙转氨酶(ALT)升高,但研究组低于对照组(P<0.05)。两组治疗结束后CD8+升高,但研究组低于对照组(P<0.05);CD4+、CD4+/CD8+、CD3+均下降,但研究组高于对照组(P<0.05)。两组治疗结束后甲胎蛋白(AFP)、糖链抗原(CA)242、CA724、磷脂酰肌醇蛋白聚糖-3(GPC3)下降,且研究组低于对照组(P<0.05)。对照组(30.00%)、研究组(24.00%)的不良反应发生率组间对比无差异(P>0.05)。结论:DSA引导下TACE化疗治疗肝癌患者,疗效可靠,可有效阻止疾病进展,同时减轻化疗所致的肝损伤和细胞免疫功能损伤。 相似文献
97.
Seiji Ito Noriko Mochizuki-Oda Kunio Hori Kazuho Ozaki Atsuo Miyakawa Manabu Negishi 《Journal of neurochemistry》1991,56(2):531-540
We recently reported that prostaglandin E2 (PGE2) stimulates phosphoinositide metabolism accompanied by an increase in intracellular free Ca2+ concentration ([Ca2+]i) in cultured bovine adrenal chromaffin cells. In the present study, temporal and spatial changes in [Ca2+]i induced by PGE2 in fura-2-loaded individual cells were investigated by digital image microscopy and were compared with those induced by nicotine and histamine. Image analysis of single cells revealed that responses to PGE2 showed asynchrony with the onset of [Ca2+]i changes. After a lag time of 10-30 s, PGE2-induced [Ca2+]i changes took a similar prolonged time course in almost all cells: a rapid rise followed by a slower decline to the basal level over 5 min. Few cells exhibited oscillations in [Ca2+]i. In contrast, nicotine and histamine induced rapid and transient [Ca2+]i changes, and these [Ca2+]i changes were characteristic of each stimulant. Whereas pretreatment of the cells with pertussis toxin (100 ng/ml, 6 h) did not block the response to any of these stimulants, treatment with 12-O-tetradecanoylphorbol 13-acetate (100 nM, 10 min) completely abolished [Ca2+]i changes elicited by PGE2 and histamine. In a Ca2(+)-free medium containing 3 mM EGTA, or in medium to which La3+ was added, the [Ca2+]i response to nicotine disappeared, but that to histamine was not affected significantly. Under the same conditions, the percentage of the cells that responded to PGE2 was reduced to 37% and the prolonged [Ca2+]i changes induced by PGE2 became transient in responding cells, suggesting that the maintained [Ca2+]i increase seen in normal medium is the result of a PGE2-stimulated entry of extracellular Ca2+. Whereas the organic Ca2(+)-channel blocker nicardipine inhibited [Ca2+]i changes by all stimulants at 10 microM, these [Ca2+]i changes were not affected by any of the organic Ca2(+)-channel blockers, i.e., verapamil, diltiazem, nifedipine, and nicardipine, at 1 microM, a concentration high enough to inhibit voltage-sensitive Ca2+ channels. These results demonstrate that PGE2 may promote Ca2+ entry with concomitant release of Ca2+ from intracellular stores and that the mechanism(s) triggered by PGE2 is apparently different from that by histamine or nicotine. 相似文献
98.
Fangzheng Wang Chuner Jiang Zhimin Ye Tongxin Liu Quanquan Sun Fengqin Yan Weifeng Qin Zhenfu Fu Yangming Jiang 《Translational oncology》2018,11(1):65-73
OBJECTIVES: To report the long-term outcome and toxicity of locoregionally advanced nasopharyngeal carcinoma (LA NPC) treated with nimotuzumab (h-R3) plus intensity-modulated radiotherapy (IMRT) with or without chemotherapy. METHODS: From May 2008 to March 2014, 3022 newly histology-proven, nonmetastatic NPC patients were retrospectively reviewed; among them, 257 patients treated with h-R3 were enrolled in this study. The patients' age range was between 10 and 76 years. The distribution of patients by disease stage was 150 (58.4%) in stage III, 88 (34.2%) in stage IV A, and 19 (7.4%) in stage IV B. All the patients received the treatment of h-R3 plus IMRT, and from them, 239 cases were also treated with cisplatin-based chemotherapy. Acute and late radiation-related toxicities were graded according to the Acute and Late Radiation Morbidity Scoring Criteria of Radiation Therapy Oncology Group. The accumulated survival was calculated according to the Kaplan-Meier method. Log-rank test was used to compare the survival difference. Multivariate analysis was performed using Cox's proportional-hazard model. RESULTS: All 257 patients had completed combined treatment; 231 patients received h-R3 plus IMRT with induction chemotherapy (IC), while 26 patients received only h-R3 plus IMRT. With a median follow-up of 48 months (range, 13-75 months), the estimated 5-year local recurrence-free survival, regional recurrence-free survival, distant metastases-free survival, progression-free survival, and overall survival (OS) rates were 94.3%, 94.8%, 91.9%, 83.4%, and 86.2%, respectively. Univariate analysis showed that age, T stage, clinical stage, and IC were related with OS. Multivariate analysis indicated that T stage and IC were independent prognostic factors for OS. The incidence of grade 3 to 4 acute mucositis and leukocytopenia was 10.9% and 19.8%, respectively, with no cases of skin rash and infusion reaction. Xerostomia was the most common late complication, and the degree of dry mouth in most survivors was mild to moderate at the last follow-up time. CONCLUSION: h-R3 plus IMRT with or without chemotherapy showed promising outcomes in terms of locoregional control and survival without increasing the incidence of radiation-related toxicities for patients. 相似文献
99.
E Ikoma 《American journal of physical anthropology》1986,69(4):483-487
Hair exhibits many interesting anthropologic and genetic features such as thickness and cross-sectional morphology. Digital hair, though not adequately studied to date, has potential importance as an anthropologic trait. A digital hair score system was devised in which a number of dorsally haired digital segments (nine segments) of the left fingers, excluding onychogenic segments, was used as a measure of the trait. Thickness and cross-section of the parietal hair of the Ojibwas, a tribe of Canadian Indians, and European Canadians residing in Ontario were compared with those of Japanese and Koreans residing in their respective countries. Segmental distribution of the digital hair in both males and females was similar between Ojibwas and Japanese, Koreans or Formosans, and was significantly larger in British and other European Canadians. Parietal hair of Ojibwas, both males and females, was thinner than that of Japanese, and thicker than that of British Canadians. The parietal hair index was almost equal between Ojibwas and Japanese in both sexes. That of British Canadians was significantly smaller. 相似文献
100.
目的:研究黑龙江省不同医疗机构之间新型协同服务模式,加强垦区各级医疗机构的信息化基础建设,建立基于医学影像存档与通信传输系统(Picture Archiving and Communications System,PACS)的数字化医疗区域。方法:将哈尔滨医科大学附属第四医院现有的影像数据归档,集成到IMPAX PACS数据中心(Internet Data Center,IDC),作为整个区域医疗的影像中心。通过IDC交换平台的延伸覆盖,以及医院信息系统(Hospital Information System,HIS)与XERO集成,可经网络调阅IDC中的影像,实现远程影像会诊。结果:建立基于IMPAX PACS的区域医疗;工程覆盖1家省会大医院和垦区2家综合性医院、5家二级医院、11家农场医院,实现联网医院间的影像学远程会诊。结论:PACS区域远程医疗系统的建立为基层百姓就医提供方便,影像学远程会诊可有效避免影像学重复检查,双向转诊、信息共享给患者带来更多的便利和实惠,具有巨大的社会效益。 相似文献