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31.
32.
60Co-γ射线辐射对车前草六项生理指标的影响 总被引:6,自引:0,他引:6
本试验探讨了60Co-γ射线不同剂量对车前草六项生理指标的影响.结果表明:可溶性糖与辐射剂量之间存在显著负相关;淀粉、蛋白质、类胡萝卜素含量以20 Gy辐射处理最高;叶绿素(a b)以30 Gy辐射处理最高,20 Gy辐射处理次之;车前草的六项生理指标以20 Gy辐射处理的表现较好. 相似文献
33.
水氮管理及品种对冬小麦光能利用率的影响 总被引:3,自引:0,他引:3
提高光能利用率(RUE)是作物获得高产的重要因素之一。遗传特性和栽培管理措施等因素通过影响作物冠层结构及冠层形成过程,进而影响作物的光能利用率。为探讨不同冬小麦品种在不同水氮管理条件下的光能利用率,于2012—2013年,在中国科学院栾城农业生态系统试验站,进行了3个冬小麦品种(‘冀麦585’、‘科农199’和‘石新828’)在3个氮水平[135 kg(N)·hm?2,180 kg(N)·hm?2,225 kg(N)·hm?2]和3个灌溉水平(70 mm,140 mm,210 mm)下的大田试验,对关键生育期光合有效辐射截获、生物量和叶面积等参数进行了测定和分析。结果表明:不同冬小麦品种的光能利用率存在显著差异(P0.05),‘冀麦585’、‘科农199’和‘石新828’的光能利用率分别为2.10 g?MJ?1、2.05 g?MJ?1和1.93 g?MJ?1。不同水氮处理对冬小麦光能利用率有一定的影响,其值为1.80~2.20 g?MJ?1;水氮因素对冬小麦光能利用率的影响不同,随着施氮水平的增加,光能利用率增加,适度的水分亏缺会产生较高的光能利用率。光能利用率增加与生物量形成呈正相关,但当生物量增加到一定程度后冬小麦产量并不随生物量的增加而增加,这与干物质量转移率随着生物量增加而降低有关。结果还显示:从拔节期到灌浆期冬小麦的光能利用率与气温存在明显的曲线关系,其在水氮条件下表现不一致。综合上述分析结果,需要适宜水氮供应才能获得适度干物质积累,提高光能利用率和有效干物质运转,最终提升冬小麦产量。 相似文献
34.
35.
K.R. Hume J.L. Johnson L.E. Williams 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2009,23(1):24-30
Background: Concurrent chemo- and radiotherapy improves outcome of certain human neoplasms but with increased signs of toxicity. Reports on adverse effects of concurrent chemo- and radiotherapy in the veterinary literature are scant.
Objective: To report adverse hematologic and gastrointestinal effects of combined carboplatin and radiation therapy in dogs.
Animals: Client-owned dogs with spontaneously occurring neoplasia.
Methods: Retrospective case study. Medical records of 65 dogs were reviewed. Criteria for inclusion were administration of radiation according to 1 of 3 fractionation schemes (19 × 3, 16 × 3, or 12 × 4 Gy) and administration of at least 1 concurrent carboplatin treatment at a dosage of 200–300 mg/m2 . Dog and treatment-related variables were analyzed for association with signs of intoxication.
Results: Median carboplatin dosage was 200 mg/m2 (range, 200–250 mg/m2 ). Twelve of 58 dogs (21%) developed grade 3 or 4 neutropenia. Eleven of 56 dogs (20%) developed grade 3 or 4 thrombocytopenia. Six of 62 dogs (10%) developed grade 3, 4, or 5 gastrointestinal toxicosis. Analysis of association of dog and treatment-related variables with signs of intoxication was hampered by the small numbers of dogs in individual groups, and no statistically significant associations were found.
Conclusions and Clinical Importance: Combined modality therapy resulted in myelosuppression and gastrointestinal toxicosis. Future studies are needed to determine whether the potential benefit of combined modality therapy outweighs the risk of decreasing chemotherapy and radiation treatment intensity. 相似文献
Objective: To report adverse hematologic and gastrointestinal effects of combined carboplatin and radiation therapy in dogs.
Animals: Client-owned dogs with spontaneously occurring neoplasia.
Methods: Retrospective case study. Medical records of 65 dogs were reviewed. Criteria for inclusion were administration of radiation according to 1 of 3 fractionation schemes (19 × 3, 16 × 3, or 12 × 4 Gy) and administration of at least 1 concurrent carboplatin treatment at a dosage of 200–300 mg/m
Results: Median carboplatin dosage was 200 mg/m
Conclusions and Clinical Importance: Combined modality therapy resulted in myelosuppression and gastrointestinal toxicosis. Future studies are needed to determine whether the potential benefit of combined modality therapy outweighs the risk of decreasing chemotherapy and radiation treatment intensity. 相似文献
36.
Hiromi KEINO Atsushi FUNAHASHI Hiroomi KEINO Chihiro MIWA Masanori HOSOKAWA Yoshihiro HAYASHI Kenji KAWAKITA 《Journal of Equine Science》2009,20(4):79-88
In this study, we applied a novel psycho-educational horseback riding (PEHR) program to
the treatment of four Japanese children with pervasive developmental disorders (PDD) in
order to facilitate the acquisition of verbal and nonverbal communication skills. The
behavioral changes in each child were evaluated using a psychological and behavioral
scale. The scale for evaluating the effect of Human-Equips-Interaction on Mental activity
(HEIM scale) was designed to assess the behavioral improvement of children based on the
following 10 items: Human relationships, Imitation, Emotional expression, Sudden physical
movement, Fixative behavior, Adaptation to change, Visual response, Fear or nervousness,
and Verbal and nonverbal communication. After taking part in the PEHR program for several
months, all subjects showed remarkably improved HEIM scores and marked improvements were
observed in eye contact with others (instructors, side walkers, and leaders) in the riding
area. A statistical difference was found in items 1, 2, 3, 6, 7, 8, and 9. However, no
statistical difference was found in items 4, 5, and 10. As the program progressed, the
children showed enhanced verbal and nonverbal communication skills, and became more
expressive in their emotional and empathetic interaction with their parents. These
observations suggest that the normal functioning of pleasurable emotions and empathy may
facilitate further improvements in joint attention, imitation and empathy, and may result
in successful verbal expression by PDD children. Therefore, horseback riding can play a
very important role in the psycho-educational support required for the communication
ability of PDD children. 相似文献
37.
MONIQUE N. MAYER HIROTO YOSHIKAWA NARINDER SIDHU 《Veterinary radiology & ultrasound》2009,50(3):319-322
We quantified the effect of tissue inhomogeneity on dose distribution in a canine distal extremity resulting from treatment with cobalt photons and photons from a 6 MV accelerator. Monitor units for a typical distal extremity treatment were calculated by two methods, using equally weighted, parallel-opposed fields. The first method was a computed tomography (CT)-based, computerized treatment plan, calculated without inhomogeneity correction. The second method was a manual point dose calculation to the isocenter. A computerized planning system was then used to assess the dose distribution achieved by these two methods when tissue inhomogeneity was taken into account. For cobalt photons, the median percentage of the planning target volume (PTV) that received <95% of the prescribed dose was 4.5% for the CT-based treatment plan, and 26.2% for the manually calculated plan. For 6 MV photons, the median percentage of the PTV that received <95% of the prescribed dose was <1% for both planning methods. The PTV dose achieved without using inhomogeneity correction for cobalt photons results in potentially significant under dosing of portions of the PTV. 相似文献
38.
MIRIAM KLEITER KARSTEN VELDE EDMUND HAINISCH ULRIKE AUER MARTIN REIFINGER 《Veterinary radiology & ultrasound》2009,50(5):560-563
A 13-month-old Standardbred Colt had a recurrent hemangioma at the level of the coronary band. Multiple excisions had led to a nonhealing skin and hoof defect. Using 14 MV electrons, a total dose of 36 Gy was administered, given as six fractions of 6 Gy twice a week. Wound healing by second intention was achieved over the next 4 months and the colt began race training 6 months after the end of therapy. Twenty months later the colt is sound and there is no evidence of tumor recurrence. 相似文献
39.
乙型肝炎病毒(HBV)是感染人类最常见的病毒性疾病之一,在慢性患者中每年发生肝硬化和肝细胞癌率分别占2%和1%.因此,乙型肝炎病毒严重威胁着人类的生命健康.我国各个民族对乙肝的治疗均有独特的方法,且效果明显,具有很大的开发潜力.笔者就近年来有关乙肝治疗的民族医药的研究及其应用情况作一概述. 相似文献
40.
乳腺癌是犬、猫等伴侣动物与人类常发疾病,作为人类及动物常患恶性肿瘤和主要致死肿瘤之一,其疾病负担仍呈逐步加重趋势,乳腺癌的预防及治疗形势愈加严峻。上皮间质转化(EMT)是乳腺癌发生发展中重要的生物学过程。EMT还可促进恶性肿瘤的侵袭、扩散及耐药,因此它在肿瘤的研究中日益受到关注,靶向于EMT是治疗乳腺癌的重要研究方向与热点。文章就EMT发生过程中细胞形态功能及标志物的变化、EMT分类及EMT与乳腺癌的关系分别展开论述,详细解析了EMT相关TGF-β/Smad、NF-κB及Wnt信号通路转导途径;随后对乳腺癌治疗药物研究进展,包括TGF-β/Smad通路抑制剂开发,相关药物、基因及细胞因子治疗前景、NF-κB通路与Wnt通路抑制剂的动物试验研究结果进行了详细论述;最后对乳腺癌的治疗发展与趋势进行了展望。深入认识信号通路调控乳腺癌EMT的生物学过程,明确其发生发展机制,寻找关键靶点及开发靶向药物,将为乳腺癌的精准治疗带来曙光。 相似文献