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951.
The clinical signs of camel sway disease in the Hexi Corridor of Gansu province were defined. The contents of eight minerals in soils, in forage and in the blood and hair of bactrian camels from this region were determined. The related blood indices were also measured. The concentration of molybdenum in soils and forage was 4.8±0.02 and 4.8±0.25 µg/g (dry matter), respectively, the copper to molybdenum ratio in the forage being only 1.3. The concentration of copper in blood and hair from the camels was 0.28±0.17 µg/ml and 3.50±1.00 µg/g, respectively. There was a hypochromic microcytic anaemia and a low level of ceruloplasmin in the blood. It is therefore suggested that sway disease of bactrian camels in this region is caused by secondary copper deficiency, mainly due to the high molybdenum content in soils and forage. The copper deficiency in the camels was aggravated during reproduction. Oral administration of copper sulphate can prevent and cure the disease.Abbreviations AKP alkaline phosphatase - BUN blood urea nitrogen - Chol cholesterol - Cp ceruloplasmin - Crt creatinine - DM dry matter - -GGT -glutamyltransferase - Hb haemoglobin concentration - LDH lactate dehydrogenase - MCH mean corpuscular haemoglobin content - MCHC mean corpuscular haemoglobin concentration - MCV mean corpuscular volume - PCV packed cell volume - RBC red blood cell count  相似文献   
952.
本试验旨在研究饲粮不同铜源及水平对育成期水貂血清铜、锌和铁含量及血清氮代谢、脂类和抗氧化指标影响,以及水貂对不同铜源的相对生物学利用率。选择60日龄健康、体重接近的水貂240只,随机分成10组,每组24个重复,每个重复1只貂。试验采用3×3+1试验设计,对照组饲喂基础饲粮,试验组分别在基础饲粮中添加3种铜源(硫酸铜、碱式氯化铜、蛋氨酸铜)和3个铜添加水平(10、25、40 mg/kg),预试期7 d,正试期45 d。结果表明:水貂血清铜含量随饲粮铜添加水平增加呈极显著线性增加( P=0.0004)。水貂血清总胆固醇( P=0.0015)、甘油三酯( P=0.0021)和高密度脂蛋白胆固醇( P=0.0101)含量随饲粮铜添加水平增加呈显著或极显著线性降低,然而水貂血清低密度脂蛋白胆固醇含量却未受饲粮铜添加水平的影响(P=0.5790)。水貂血清铜蓝蛋白和铜锌超氧化物歧化酶活性均随饲粮铜添加水平增加呈极显著线性升高( P=0.0001)。以血清铜蓝蛋白活性为指标,以硫酸铜为参比标准物(100%),碱式氯化铜和蛋氨酸铜的相对生物学利用率分别为109.93%和131.06%。以血清铜锌超氧化物歧化酶活性为指标,以硫酸铜为参比标准物(100%),碱式氯化铜和蛋氨酸铜的相对生物学利用率分别为111.01%和118.10%。由此可见,饲粮添加40 mg/kg的铜(基础饲粮铜含量8.05 mg/kg)能提高育成期水貂血清抗氧化酶的活性;育成期水貂3组铜源的相对生物学利用率为:蛋氨酸螯合铜>碱式氯化铜>硫酸铜。  相似文献   
953.
954.
Copper and arsenic K-edge X-ray absorption fine structure spectroscopy (EXAFS) of pine wood (Pinus radiata) treated with chromated copper arsenate (CCA) timber preservative have been measured. Refinement of the data is consistent with arsenate anions bound to chromium and copper ions isolated from other heavy elements, regardless of depth into the wood. This constitutes the first substantive analysis of CCA's fixation products and has a number of implications for models of fixation.  相似文献   
955.
临于含双齿膦配体的单、双或多核铜(Ⅰ)配合物具有独特的结构和催化性能,利用双齿膦配体1,1-双(二苯基膦)甲烷(dppm)的还原性,通过配体与二价铜盐的还原反应,合成了2个双核配合物,并通过元素分析、红外光谱(IR)、X射线粉末衍射、电化学性能及热重分析(TG)等对配合物进行了表征。  相似文献   
956.
壳聚糖铜复合物处理后马尾松的防白蚁效果   总被引:1,自引:0,他引:1  
Chitosan is a non-toxic natural biopolymer derived from chitin, which is the second most abundant natural polymer after cellulose in the world. Chitosan is easily cheated with metal salts and form chitosan metal complexes (CMC). In this study, Masson Pine (Pinus massoniana) as test species, chitosan copper complex(CCC), modified chitosan copper complex (M-CCC) and CCB as wood preservatives to termite attack. The experiment was conducted according to AWPA E1-97(AWPA 1999) and GB/T18260-2000 in order to evaluate the termite resistance effects of CCC and M-CCC in comparison with CCB. Results showed that all of the chosen preservatives had good resistance against termites ( Coptotermes formosanus ), among which, M-CCC beheld the best, and the synthetical rating exceeded 100.  相似文献   
957.
Hemibastadin derivatives, including the synthetically-derived 5,5′-dibromohemibastadin-1 (DBHB), are potent inhibitors of blue mussel phenoloxidase (PO), which is a key enzyme involved in the firm attachment of this invertebrate to substrates and, thus, a promising molecular target for anti-fouling research. For a systematic investigation of the enzyme inhibitory activity of hemibastadin derivatives, we have synthesized nine new congeners, which feature structural variations of the DBHB core structure. These structural modifications include, e.g., different halogen substituents present at the aromatic rings, different amine moieties linked to the (E)-2-(hydroxyimino)-3-(4-hydroxyphenyl)propionic acid, the presence of free vs. substituted aromatic hydroxyl groups and a free vs. methylated oxime group. All compounds were tested for their inhibitory activity towards the target enzyme in vitro, and IC50 values were calculated. Derivatives, which structurally closely resemble sponge-derived hemibastadins, revealed superior enzyme inhibitory properties vs. congeners featuring structural moieties that are absent in the respective natural products. This study suggests that natural selection has yielded structurally-optimized antifouling compounds.  相似文献   
958.
Forest gap in alpine forests may redistribute the hydrothermal conditions in winter and growing season, which may affect the releases of copper and zinc in foliar litter during decomposition. However, the details of this process are largely unknown. Foliar litters of willow (Salix paraplesia), larch (Larix mastersiana), fir (Abies faxoniana), azalea (Rhododendron lapponicum), birch (Betula albosinensis) and cypress (Sabina saltuaria) were selected in an alpine forest of eastern Tibetan Plateau. The litterbags were placed on the forest floor from gap center, canopy gap edge and expanded gap edge to closed canopy. Zinc and copper contents were studied as litter decomposition proceeded. After one year of decomposition, zinc accumulated in all foliar litters regardless of gap positions, but copper accumulated in the litters of fir, azalea and cypress. Separately, copper was released from all foliar litters in winter, whereas zinc in litters of larch, azalea, birch and cypress was released in winter. Moreover, both copper and zinc accumulated during the growing season regardless of litter species. Nevertheless, higher accumulation rates were observed under closed canopy compared with other gap positions. These results suggest that forest gap slows the releases of copper and zinc in foliar litter during forest regeneration in these cold biomes.  相似文献   
959.
Long-term effects of integrated application of organics and chemical fertilizers on transformation of copper (Cu) into various chemical pools and their availability under rice (Oryza sativa L.)–wheat (Triticum aestivum L.) cropping system were investigated in the ongoing long-term fertilizer experiment initiated in 1991 kharif season (May–October) at the research farm of Chaudhary Sarwan Kumar Himachal Pradesh Agricultural University on an acidic soil in the Western Himalayas of India. The continuous use of chemical fertilizers alone for 20 years brought about marked depletion in all forms of copper except organically bound Cu (Cu-PYR) compared to buffer plots. Integrated use of organics and chemical fertilizers gave higher content of Cu forms over chemically treated plots except Cu occluded by free oxides (Cu-OX). Residual Cu was the most dominant form of copper contributing about 67% of the total Cu. Soil solution and exchangeable Cu (Cu-CA) was the most important fraction of copper contributing toward DTPA (diethylene triamine pentaacetic acid) extractable Cu. Content of DTPA extractable Cu increased over control when chemical fertilizers were applied in conjunction with different organics, whereas DTPA Cu content declined over control with application of chemical fertilizers alone for the last 20 years.  相似文献   
960.
ABSTRACT

Fingerling channel catfish Ictalurus punctatus were exposed to Ichthyophthirius multifiliis-infested fish until immature trophonts developed. The fish were transferred to individual static fiberglass tanks filled with 600 L of pond water (total alkalinity and total hardness was 220 mg/L and 101 mg/L, respectively) and were treated with 0, 1.1, 2.2, 3.3, or 4.4 mg/L copper sulfate (CuSO4 · 5H2O) every other day for four treatments to evaluate its effectiveness to control mortality associated with ichthyophthiriasis. Water temperature was maintained at 18 ± 1°C. Fish were observed for ten days post-treatment and mortalities were recorded. Results indicate that half of the recommended dose (1.1 mg/L CuSO4) is needed to effectively control an occurrence of ichthyophthiriasis under the conditions of this study. However, fish culturists should be aware that effective CuSO4 treatment of ichthyophthiriasis on channel catfish raised in ponds may be influenced by water chemistry characteristics and suspended materials such as pond sediments.  相似文献   
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