输电塔-螺旋锚基础-土体系相互作用的影响因素分析

提出了2种计算输电塔-螺旋锚基础-土体系相互作用的简化计算模型,用有限元原理编程分析了风荷载作用下计算模型不同、锚杆直径变化、土质状况差异对体系相互作用的影响,为螺旋锚基础的推广和设计理论的完善提供了一定的理论基础。     

A RETROSPECTIVE ANALYSIS OF 140 DOGS WITH ORAL MELANOMA TREATED WITH EXTERNAL BEAM RADIATION

Despite the early notion that canine oral malignant melanoma is radioresistant, recent data suggest that external beam radiotherapy is effective in local tumor control. However, optimal fractionation schedules have not been established. The high rate of regional and distant metastasis is another problem that has hindered long-term control. The role of chemotherapy in the management of canine oral melanoma has also not been determined. In this study, data from 140 dogs irradiated at North Carolina State University were evaluated with the following objectives: (1) to compare the efficacy of three radiation therapy protocols (36 Gy, 9 Gy x 4 fractions; 30 Gy, 10 Gy x 3 fractions; or >45 Gy, 2-4 Gy x 12-19 fractions) for the treatment of dogs with oral malignant melanoma, (2) to identify any host or tumor factors influencing prognosis, and (3) to determine the impact of systemic chemotherapy on treatment outcome. Information regarding response to therapy, disease progression, and survival were determined from the medical records or from information obtained by telephone or mail survey. Relationships between host, tumor, and treatment variables and outcome measures (response, time to first event, and survival) were evaluated using Fisher's exact test (response) and the Cox regression model (time to first event and survival). The median time to first event for the 140 dogs was 5.0 months (95% C.I., 4-6 months) and the median survival was 7.0 months (95% C.I., 6-9 months). In the univariate analysis, the following variables were associated with increased time to first event and survival: (1) rostral tumor sublocation; (2) lack of bone lysis observed on skull imaging, and (3) microscopic tumor burden. In a multivariate analysis of 111 dogs with complete data for these variables, tumor sublocation, bone lysis, and tumor volume were identified as joint predictors of time to first event (p < .001, p < .001, and p = .04, respectively) and survival (p < .001, p < .001, and p = .05, respectively). There were no differences in response, time to first event and survival between the three radiation therapy protocols used. Systemic chemotherapy had no impact on the development of metastatic disease, time to first event, or survival, although the dosages used in this study were suboptimal. External beam radiation therapy is effective in local disease control of canine oral malignant melanoma; however, the optimal fractionation scheme has yet to be determined. The high metastatic rate observed with this disease and the inefficacy of systemic chemotherapy indicate that further investigation into novel therapies is warranted.     

岳阳市南湖水环境污染治理方案优化分析

为了防止南湖水质进一步恶化，改善与提高南湖水环境质量，针对南湖水环境污染现状，提出了集中治理，分散治理及综合治理3种方案，并对这些方案进行了优化分析。     

肥料三要素与日本落叶松苗木生理的关系

对肥料三要素与日本落叶松苗木生理的关系进行了研究，结果表明，叶绿素含量与氮、磷肥关系密切（rN=0.91^**,rp=0.61^**)；混施三要素比单施氮肥能提高苗木根系吸收能力；并且三要素混施比单施氮肥提高苗茎纤维素含量，平均提高10．7％。生产上适宜三要素施肥比例为N：P2O5：K2O＝1：0．6：0．4。     

运用营养调控措施降低动物养殖业环境污染

本文在分析养殖业对环境污染的基础上，探讨了通过营养调控降低动物养殖业对环境污染的潜力和技术方法，包括选用易消化饲料原料；研制最优日粮配方；饲料的合理加工和调制；应用安全高效饲料添加剂；使用生物活性肽调控日粮浓度；禁止某些非营养性添加剂的使用；采用多阶段、公母分开的饲养方式等，以从根本上解决养殖业的环境污染问题。     

影响猪肌肉品质因素的初步研究

通过对华中农业大学种猪场的抗应激品系的猪采用不同屠宰方法，对抗应激品系的猪和应激敏感的猪采用相同的屠宰方法和测定时间，其结果之间差异极显著，表明影响猪肌肉品质的因素既有内因因素，又有外因因素。对抗应激猪和应激猪采用不同时间连续测定，结果应激狸的不同时间测定值差异不显著，抗应激猪的不同时间测定值差异较大，说明时间对抗应激猪的肉质有一定的影响，因此必须选择正确的评定方法才能有效地区别优质肉与劣质肉。研     

Antibody response in sea bass (Dicentrarchus labrax L.) in relation to water temperature and oxygenation

The influence of water temperature and water oxygenation on the specific antibody response was evaluated by indirect ELISA in sea bass (Dicentrarchus labrax L.) immunized against human‐γ‐ globulins emulsified in Freund's complete adjuvant. A higher antibody response was observed in fish reared at 24 and 30 °C, than at 12 and 18 °C. For the fish group reared at 24 °C, the immunological observation was carried out until 300 days after immunization. At the end of this period, fish kept at 24 °C still showed immunological competence, although the antibody response began to decrease significantly from 120 days after the immunization. Fish reared under mild hyperoxia and normoxia conditions had higher antibody responses than fish reared under mild hypoxia conditions. Moreover, at the end of the experimental period of 56 days the antibody response of fish reared under hyperoxia conditions was significantly higher than the immune response detected in fish reared under normoxia and hypoxia conditions.     

蜂群内主要环境因素的研究

采用可测量温度、湿度和CO2 、O2 体积分数的电子显示仪 ,对意蜂 (Apismelliferaligustica)群内的子脾区、无子脾区和隔板外的温度、湿度、CO2 及O2 体积分数 4个主要环境因素进行测量。结果表明 :温度、湿度和CO2体积分数在子脾区最高 ,无子脾区次之 ,隔板外最低 ,但湿度的规律不是十分明显。O2 体积分数则呈相反的规律     

Sequential expression of myogenic regulatory factors in bovine skeletal muscle and the satellite cell culture

Myogenic regulatory factors (MRFs) are important in the control of skeletal muscle development. To understand myogenic regulation by MRFs in bovine adult muscle cells, their expressions, namely that of Myf5, MyoD, myogenin, and MRF4 in the biceps femoris muscle (BF) and in the satellite cell culture, were analyzed by RT-PCR. In the BF, all four MRFs were expressed and in particular, myogenin and MRF4 were strongly expressed, whereas Myf5 was faintly expressed. The satellite cells prepared from the BF expressed Myf5, but only a trace of MyoD, at day 9 of culture. During the growth of the cells to day 14, the MyoD and myogenin expressions gradually increased, and that of MyoD expression reached its maximum at the confluence of the culture. After induction of myogenic differentiation by a serum-free medium at day 14, Myf5 expression gradually decreased, and the up-regulated expression of MyoD was suppressed, whereas myogenin expression continued to increase sharply. Following the myogenin expression, MRF4 also drastically increased toward the myotube formation of the cells. When huge myotubes were formed at day 18, Myf5 was expressed at a low level, whereas the MyoD expression remained at a moderate level.