青海白唇鹿公鹿血钾指标和红细胞钾型的研究

采用火焰光度法对青海省大通种牛场18头白唇鹿公鹿三项血钾指标和红细胞钾型进行了研究。结果发现:①被检青海白唇鹿公鹿的血清钾离子浓度为3.7±0.8mmol/L,全血钾离子浓度为27.4±3.0mmol/L,红细胞钾离子浓度为75.4±10.1mmol/L;②按红细胞钾离子浓度判定,全部被检青海白唇鹿公鹿的红细胞钾型为高血钾型。     

Effect of membrane environment at high temperature on delayed rectifier K+ channel in hypothalamus neurons

AIM: To observe the effect of high temperature on the delayed rectifier K⁺ channel(I_K) in hypothalamus neurons METHODS: The kinetic properties of I K were measured by cell-attached mode of patche-clamp technique RESULTS: The conductance, long-term open constant(τ _o2) and open probability(Po) of I_K increased with increase of temperature (P <0.05), while more burst open and multi-order open were recorded Many types of currents occurred after heat stress at 43℃,and voltage-dependent property reduced and even depressed CONCLUSIONS: The activating action of I_K might be affected obviously by high temperature, the coupling between I K and body fever or heatstroke remained to be established.     

柑桔配施氮、磷、钾肥效应研究初报

本试验研究了在同一施氮水平下，不同水平磷、钾配施及施用不同种类钾肥对柑桔营养、产量及品质的效应。结果表明，紫色黄泥土锦橙园采用适当氮、磷、钾肥配合施用对提高单产及改善果实品质具有明显作用，以株施Ｎ４６０９、Ｐ_２Ｏ_４００ｇ、Ｋ_Ｏ５６０ｇ效果最佳，经济效益也最大。在一定范围内，叶片中的磷、钾养分含量都随磷、钾化肥用量的增加而提高。     

A nutritional disorder in pistachio from near Athens,Greece

Abstract

A problem pistachio orchard near Athens, Greece had many trees with severely scorched leaves. Half or more of each leaflet v/as brown and dry but tips and edges were most affected. Affected leaves were also of lighter green color than normal leaves and slightly resembled Fe deficiency. Leaf analysis indicated low K, low Fe, and high Mg. Irrigation water contained moderate levels of Mg and Na chlorides and chloride toxicity was possibly another factor. Improvement was observed when Fe chelate was applied to the orchard but Mg‐induced K deficiency was possibly a major factor. Response to K applied to soil was not observed after four months, however.     

磷钾素处理对红葱生长和品质的影响

以1/2 Hoagland完全营养液配方为基本配方,研究了不同磷钾水平对红葱生长和品质的影响。结果表明：在相同磷浓度下,随着钾浓度升高,红葱单丛质量、单丛叶片数逐渐增加,单丛分蘖数、株高、假茎长和假茎粗有增大趋势|食用部分可溶性糖含量逐渐升高,叶片丙酮酸和大蒜素含量降低。磷浓度为0.25 mmol·L-1时,随着钾浓度升高,红葱食用部分VC含量逐渐增加,硝酸盐含量和可溶性蛋白含量均先增加后降低。P0.125K1.5处理红葱叶片和假茎总酚及总黄酮含量最高。     

中国三大自然区域紫花苜蓿土壤速效钾丰缺指标和推荐施钾量

为给内蒙古高原区、黄土高原区和西北荒漠绿洲区紫花苜蓿测土施肥奠定科学基础,采用零散实验数据整合法以及养分平衡-地力差减法,开展了三大自然区域紫花苜蓿土壤速效钾丰缺指标和推荐施钾量研究.结果表明,内蒙古高原区紫花苜蓿土壤速效钾第1～4级指标依次为≥342mg/kg、89～342mg/kg、24～89mg/kg和<24mg...     

钾对猕猴桃果实品质与贮藏的影响

为提高猕猴桃果实品质与耐贮性,以7年生美味猕猴桃品种米良1号(Actinidiadeliciosacv.Miliang-1)为试材,进行果实生长发育期施钾处理对果实品质与贮藏性能影响的研究。结果表明:适量施钾能提高果实硬度及可溶性固形物与维生素C含量,降低果实含酸量,提高果实耐贮性。在0-4℃贮藏条件下,以株施纯K2O80g+叶面喷施0.3%硫酸钾处理果实贮藏效果最佳,贮藏73d时,其软果率最低(15.56%),果肉硬度最高(0.27MPa)。同时果实维生素C含量的下降趋势较为平缓,果实贮藏寿命延长。贮藏6个月时,株施纯K2O80g+叶面喷施0.3%硫酸钾处理的果实好果率(68.89%)明显高于对照果实(0)。     

Risk Factors for the Development of Hypokalemia in Neonatal Diarrheic Calves

Background

Neonatal diarrheic calves have a clear negative potassium balance because of intestinal losses and decreased milk intake but in the presence of acidemia, they usually show normokalemic or hyperkalemic plasma concentrations.

Objectives

To assess whether marked hypokalemia occurs in response to the correction of acidemia and dehydration and to identify factors that are associated with this condition.

Animals

Eighty‐three calves with a clinical diagnosis of neonatal diarrhea.

Methods

Prospective cohort study. Calves were treated according to a clinical protocol using an oral electrolyte solution and commercially available packages of 8.4% sodium bicarbonate, 0.9% saline and 40% dextrose infusion solutions.

Results

The proportion of hypokalemic calves after 24 hours of treatment (19.3%) was twice as great as it was on admission to the hospital. Plasma K⁺ after 24 hours of treatment was not significantly correlated to venous blood pH values at the same time but positively correlated to venous blood pH values on admission (r = 0.51, P < .001). Base excess on admission (Odds ratio [OR] = 0.81, 95% confidence interval [CI] = 0.70–0.94), duration of diarrhea (OR = 1.37, 95% CI = 1.05–1.80), milk intake during hospitalization (OR = 0.54, 95% CI = 0.37–0.79) and plasma sodium concentrations after 24 hours (OR = 1.12, 95% CI = 1.01–1.25) were identified to be independently associated (P < .05) with a hypokalemic state after 24 hours of treatment.

Conclusions and Clinical Importance

Findings of this study suggest that marked depletion of body potassium stores is evident in diarrheic calves that suffered from marked metabolic acidosis, have a low milk intake and a long history of diarrhea.     

Suppressive effect of potassium silicate on powdery mildew of strawberry in hydroponics

From 1996 to 1997, potassium silicate (SiO₂) was tested at 0, 25, 50, and 100mgl^–1 in hydroponics to control powdery mildew. Other elements were added in the usual amounts, and the strawberries were cultivated hydroponically in a greenhouse for 4 months (from October to January). The powdery mildew spread in the control plot, but little mildew developed in the plot with 25mgl^–1 silicate, and none in plots with more than 50mgl^–1 silicate. The suppressive effect lasted for about 4 months on fruits and even longer on leaves. On analysis of mineral content in the leaves, only the silicate content differed markedly between the control and treated plants. Nitrogen, phosphate, potassium, and calcium contents did not differ greatly. The maximum silicate content was about 24 times that of the control, and disease severity decreased significantly when the content was more than 1.5% in the leaves. The hardness of the strawberry leaves, measured by a creep meter, was increased by the silicate treatment.     

不同形态钾肥对马铃薯产量及品质的影响

采用随机区组设计,研究了在施入等量钾肥的前提下,硫酸钾及氯化钾配施对马铃薯植株生育性状、氨基酸、钾含量等品质和产量及商品薯率的影响.结果表明,等量不同形态钾肥对植株株高和主茎数有一定的影响,对其他生育性状基本无影响;对块茎中蛋氨酸含量无显著影响,对其他类型氨基酸、总氨基酸、还原糖和钾含量有一定影响;对马铃薯产量、经济效...