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11.
本文报告了三明市区家鼠寄生革螨的种类、组成、季节消长情况。观察一周年,共捕鼠711只,带螨鼠143只,带螨率为20.11%,检集革螨871只,鼠革蛲指数为1.23只/鼠,鉴定为3属4种即毒厉螨、纳氏厉螨、柏氏禽刺螨和鼠颚毛厉螨;毒厉螨为优势种,占81.86%,平均螨指数为1.00只/鼠,各宿主动物间带情况存在差异。以褐家鼠最高,达37.20%,螨指数为2.72只/鼠,革螨常年活动,以4-6月、83 相似文献
12.
An experiment was conducted with Saanen goats fed fresh grass ad libitum to compare 51Cr-mordanted fibre and even-chain alkanes sprayed onto either grass leaves or stems to estimate faecal output, total mean retention time (TMRT) and parameters obtained from faecal marker concentration curves, such as k1 (slow rate of passage), k2 (fast rate of passage) and transit time (TT). 51Cr-mordanted grass showed the lowest fractional rates of passage (k1 and k2) and hence the largest value of TMRT. There were not significant (P > 0.05) differences between even-chain alkanes sprayed onto leaves or stems for k2, TT and TMRT, but k1 estimates were higher (P < 0.05) for stems than for sprayed leaves. Despite the marker used, TMRT values were negatively correlated with the level of dry matter intake (r = − 0.81, − 0.80 and − 0.80 for 51Cr-mordanted fibre and even-chain alkanes adsorbed onto leaves or stems, respectively). Average faecal outputs estimated from faecal concentrations of 51Cr-mordanted fibre and even-chain alkanes were not different from the actual outputs but there were differences between markers in the accuracy of estimation. The highest mean square prediction error (MSPE) and the poorest correlation between observed and estimated faecal output values corresponded to even-chain alkanes adsorbed onto stems. Values estimated using 51Cr-mordanted fibre and even-chain alkanes adsorbed onto leaves were significantly correlated with faecal outputs (r = 0.94 and r = 0.92, respectively), with MSPE being greater for the latter marker. 相似文献
13.
蜜蜂是设施农业的重要授粉昆虫,授粉蜂群的状况可能影响授粉效率的高低。通过意大利蜂(Apismellifera)对温室草莓、油桃的6次授粉重复试验,采集授粉蜂群的蜂子比值与出勤率的数据,分析蜂子比值与出勤率的相关性。结果表明,蜂子比值与工蜂出勤率之间呈显著的负相关(P<0.05),其相关系数分别为-0.8470、-0.6543、-0.7616、-0.6969、-0.6740和-0.8477,说明在正常范围内,温室授粉蜂群的出勤率随蜂子比值的减小而提高,也就是说,授粉蜂群内的子脾越好,蜜蜂出勤采集的积极性越高。 相似文献
14.
Deborah S. Greco Rod A.W. Rosychuk Gregory K. Ogilvie Lynn M. Harpold Camilla H. Van Liew 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1998,12(1):7-10
Thirty adult, client-owned dogs were diagnosed with hypothyroidism based on history, physical examination findings, hematologic and biochemical abnormalities, thyrotropin (TSH) response testing, endogenous canine thyrotropin (cTSH) concentration, or both, and total serum thryoxine concentration. All dogs received levothyroxine (L-thyroxine) at an initial dose of 22 μg/kg PO sid in either a tablet (13 dogs) or chewable form (17 dogs). Energy expenditure of each dog during apparent rest was estimated with an open-flow indirect calorimetry system by determining the rates of carbon dioxide production and oxygen consumption. Energy expenditure of apparent rest (EE) was lower in untreated hypothyroid dogs compared with reference values for EE. After treatment with L-thyroxine, EE of the hypothyroid dogs was significantly ( P < .05) higher than pretreatment values. 相似文献
15.
基质和激素对无刺枸骨扦插成活率及其生长影响研究初报 总被引:1,自引:0,他引:1
无刺枸骨在5种不同基质中,以及在经用NAA,IAA和IBA等3种激素处理的山黄土中扦插后,对其下端伤口愈合率、生根率、成苗率以及苗高、地径、新梢长、根数量、最大根长、最小根长、根系幅度和鲜重等11个指标进行了研究。结果表明:在3号基质(山黄土与珍珠岩容积比为1∶1)中插穗下端伤口愈合率、生根率、成苗率分别为90.67%,85.33%和71.33%,高于其他基质中的插穗,且3号基质中苗高、新梢长、最大根长、最小根长和鲜重等5个指标的平均值也都优于其他几种基质,与对照(砻糠灰)相比,增幅分别为0.18%,55.56%,22.80%,30.00%和13.66%;100 mg/L NAA浸泡2 h或1 000 mg/L IBA速蘸5 s,能显著提高插穗的下端伤口愈合率、生根率和成苗率。其中,经100 mg/L NAA处理过后的插穗,其苗高、新梢长、根系数量、鲜重等指标较对照(清水)增幅分别为18.79%,128.57%,43.90%和14.39%,生长优势最强。 相似文献
16.
A modified rate equation, in which the diffusion of reagent was taken into consideration, was proposed and applied to results reported previously for the acetylation of wood. The equation was fitted more successfully to the prolonged as well as the early stage of the reaction than a common first-order rate equation. Although the conclusions were virtually unchanged, the reliability was enhanced because reaction parameters such as the rate constant, ultimate extent of the reaction, and activation energy calculated for the modified equation were based on much more data than those reported previously. The equation proposed here may be applicable not only to acetylation but to other chemical modifications of cellulosic materials in heterogeneous systems. 相似文献
17.
SONG Fu-nan YANG Chuan-ping LIU Xue-mei LI Gong-bin 《林业研究》2006,17(1):13-16
The injury tolerance of cell plasma membrane and the correlative enzymes activities of plasma-membrane protection system in the Ulmuspumila leaves treated by nine concentrations (0.3%, 0.6%, 0,9%, 1,2%, 1.5%, 1.8%, 2,1%, 2.4%, 3.0%) of Na2CO3 and NaHCO3 mixtures were studied in a greenhouse of Northeast Forestry University, Harbin, China. The rate of electrolyte leakage (REL) and SOD (Superoxide dismutase) activity in leaves of different samples were determined. Results showed that the REL in leaves of U. pumila presented a slowly increasing trend at the salt concentrations less than 1.5%, which indicated that cell plasma membrane of U. pumila leaves had rather strong resistance to the injury of salt ion, and had a significant increase at the salt concentrations more than 1.5%. The SOD activities in leaves of U, pumila presented an increased trend at salt concentrations less than 1.5%, the growth of seedlings did not decline, and tress and leaves had no symptom of injury, while the salt concentrations exceeded 1.5%, SOD activities sharply decreased and REL increased promptly. 相似文献
18.
19.
Kenaf (Hibiscus cannabinus) plants are widely known for their contribution to the global and regional environment because of their ability to fix CO2. On the other hand, some scientists have doubts about CO2 fixation by kenaf and have misgivings about the effect of kenaf on the ecosystem. We have characterized the structural characteristics
of cell walls of bast fibers, cores, roots, and leaves of kenaf during the maturation of plants and investigated the rate
of photosynthesis. During maturation of the kenaf plant the cellulose (bast fiber 52–59%, core 44–46%) and lignin (bast fiber
9.3–13.2%, core 18.3–23.2%) contents increased significantly. The aromatic composition of the lignin of bast fiber was significantly
different from that of the core lignin and of other plants. The lignin of bast fiber appears similar to pure syringyl lignin.
Fixation of CO2 by kenaf plants and their contribution to the global environment are discussed. A significatly high rate of photosynthesis
of kenaf plants was observed compared to that of woody plants in Japan, but the amount of CO2 fixation depends on the characteristics of the plantation. If the kenaf was planted in high density, about twice as much
CO2 was fixed as was fixed by trees in a tropical rain forest.
Received: April 22, 2002 / Accepted: July 24, 2002
Acknowledgments This project was supported by the Science and Technology Agency (STA) fellowship of the Japan International Science and Technology
Exchange Center (JISTEC), which has been successfully applied by Dr. Shuji Hosoya, Forestry and Forest Products Research Institute.
We thank Dr. Toshio Sumizono and Mr. Masao Sakurai, Forestry and Forest Products Research Institute, for their kind help in
determining the rate of photosynthesis and cultivating the kenaf plants, respectively. We also express our appreciation to
Dr. Quang Hung Le, College of Agriculture and Forestry, Ho Chi Minh City, Vietnam for offering information about the cultivation
of kenaf at Thu Duc District, Ho Chi Minh City. 相似文献
20.