奶牛难产激发应激性急性肾上腺皮质功能不全——心衰、水电解质严重失调辩析

应激性急性肾上腺皮质功能不全症的病理机制十分复杂,目前人医的各类文献中大都以“垂体—肾上腺轴”功能不全、功能衰竭、或发生广泛性出血坏死性病演作解释。本病在奶牛分娩难产过程中并不少见,病牛的症状表现以心衰和失钠性低血症为主征。但在兽医临床上由于认识不足,曾有不少中外学者将奶牛产后卧地不起的各类疾病,含糊地统称为“母牛睡倒爬不起来综合征”;更由于救治不当,病牛常以淘汰或死亡告终。本文通过对一具体典型病例辨析,着重讨论了本病的基本病理反应和确立诊断依据,强调对本病救护施治时应遵循的基本原则,供同道们在分析和解决这一实际问题时参考。     

Serum lipase determination in the dog: a comparison of a titrimetric method with an automated kinetic method

An enzymatic, kinetic method for determining serum lipase activity was evaluated and compared to a standard manual method for use in dogs. The kinetic method was a commercial kit adapted for use on a tandem access clinical chemistry analyzer and utilized a series of coupled enzymatic reactions based on the hydrolysis of 1,2-diglyceride by lipase. The manual method was the Cherry-Crandall technique based on the titration of base against the acid formed by hydrolysis of an olive oil substrate by lipase. The correlation between the two methods was very good (r = 0.94). The reference range for 56 clinically healthy dogs assayed by the kinetic method was 90 to 527 U/L. Diseases associated with a greater than twofold elevation in serum lipase activity as determined by the kinetic method included pancreatitis, gastritis with liver disease, and oliguric renal failure with metabolic acidosis. In some cases, pancreatitis was seen with other clinical problems, such as gastroenteritis, diabetic ketoacidosis, duodenal mass, disseminated intravascular coagulation, and septic peritonitis. Diseases associated with serum lipase activity within the reference range or elevated less than twofold included gastritis, gastric ulcer, cholestasis, phenobarbital-induced hepatopathy, colitis, copper hepatopathy, abdominal hematoma, apocrine gland adenocarcinoma, and thrombocytopenia with pneumonia.     

Characterisation of energy-dependent efflux of imazalil and fenarimol in isolates of Penicillium italicum with a low,medium and high degree of resistance to DMI-fungicides

Differential accumulation of [¹⁴C]imazalil and [¹⁴C]fenarimol by germlings of wild-type and DMI-resistant isolates ofPenicillium italicum was studied at various pH values. At pH 7 and 8 the low-resistant isolate E_300–3 accumulated 22% and 35%, respectively, less imazalil than the wild-type isolate W₅. Imazalil accumulation at pH 5 and 6 was similar. Isolate E_300–3 also accumulated less fenarimol as compared with the wild-type isolate. This difference was much more obvious than for imazalil and was observed at all pH values tested. Differences in accumulation of both imazalil and fenarimol between low (E_300–3), medium (H₁₇) and high resistant (I₃₃) isolates were not observed. These results suggest that decreased accumulation of DMIs is responsible for a low level of resistance only and that additional mechanisms of resistance might operate in isolates with a medium and high degree of resistance. With all isolates fenarimol accumulation was energy-dependent. This was not obvious for imazalil.The wild-type and DMI-resistant isolates had a similar plasma membrane potential as determined with the probe [¹⁴C]tetraphenylphosphonium bromide ([¹⁴C]TPP⁺). Various test compounds, among which ATPase inhibitors, ionophoric antibiotics and calmodulin antagonists, affected the accumulation of [¹⁴C]TPP⁺, [¹⁴C]imazalil and [¹⁴C]fenarimol. No obvious correlation between the effects of the test compounds on accumulation levels of the fungicides and [¹⁴C]TPP⁺ could be observed. These results indicate that the plasma membrane potential does not mediate the efflux of DMI fungicides byP. italicum.     

某类高阶非线性偏微分方程组弱解的正则性

本文研究一类2k阶非线性偏微分方程组之解的正则性,没有假定通常的椭圆性条件而只假定所谓"无穷远处"的椭圆性条件,证明了解的k-1阶导数为李普希兹连续的.     

Trichoderma harzianum produces nonanoic acid, an inhibitor of spore germination and mycelial growth of two cacao pathogens

An isolate of Trichoderma harzianum Rifai from an infected cacao pod produces and secretes nonanoic (pelargonic) acid into a liquid culture medium. Nonanoic acid (NA) was very inhibitory to spore germination and mycelial growth of two cacao pathogens, Crinipellis perniciosa Stahel and Moniliophthora roreri Cif. H.C. Evans. It was highly active causing 75% inhibition of spore germination in an in vitro assay at a rate as low as 0.09 μM for M. roreri and 0.92 μM for C. perniciosa. Mycelial growth was comparatively less sensitive to inhibition, but still there was a 75% reduction in growth with 0.62 μM in M. roreri and 151 μM NA in C. perniciosa. In contrast, NA did not affect Trichoderma mycelial growth or spore germination at concentrations that were inhibitory to the pathogens. 6-pentyl-α-pyrone was also produced and secreted into the medium by T. harzianum, however; it was not antagonistic to the cacao pathogens. Although a number of metabolites produced by Trichoderma spp. have been identified in the past, this is the first report of NA production and secretion by any Trichoderma. The results suggest that NA may play a role in the successful use of some Trichoderma spp. isolates in the biocontrol of fungal diseases of plants.     

Molecular cloning, expression, and characterization of a phi-type glutathione S-transferase from Oryza sativa

The structural gene for glutathione S-transferase in Oryza sativa was successfully cloned from a cDNA library by the polymerase chain reaction method. The deduced amino acid sequence of this gene showed 44-66% similarity to the sequences of the class phi GSTs from Arabidopsis thaliana and Zea mays. This gene was expressed in Escherichia coli with the pET vector system and the gene product was purified to homogeneity by GSH-Sepharose affinity column chromatography. The expressed OsGSTF3-3 was a homo-dimer composed of 24 kDa subunit and its pI value was approximately 7.3. The OsGSTF3-3 was retained on GSH affinity column and its K_m value for GSH was 0.28 mM. The OsGSTF3-3 displayed high activity toward 1-chloro-2,4-dinitrobenzene, a general GST substrate and also had high activities towards acetanilide herbicides, alachlor, and metolachlor. The OsGSTF3-3 was highly sensitive to inhibition by benastatin A and S-hexyl-GSH. From these results, the expressed OsGSTF3-3 is a phi class GST and seems to play an important role in the conjugation of the chloroacetanilide herbicides.     

甜樱桃芽酚类物质含量及相关酶活性变化与自然休眠的关系

 以7年生甜樱桃‘红灯’和‘早红宝石’为试材, 研究了酚类物质含量及相关酶活性在自然休眠期间的动态变化, 探讨了温度对酚类物质含量的影响。结果表明, 甜樱桃芽酚类物质在自然休眠期间持续缓慢增加, 随休眠的结束, 含量急剧下降, 不同品种之间有差异, 自然休眠结束后总酚含量降至最低。花芽中的酚类物质含量略高于叶芽, 多酚氧化酶( PPO) 、苯丙氨酸解氨酶( PAL) 活性差别不大; 不同需冷量的品种之间差异明显。芽中PAL活性与总酚含量的变化趋势呈正相关。而PPO活性在自然休眠期间逐渐升高。低温(5℃) 促进酚类物质的积累, 中期使其提前达到高峰并进入下降阶段, 后期加速其降低;高温(20℃) 效果相反, 变温(5℃/20℃) 效果不明显。     

用吹扫捕集法测定十字花科蔬菜中挥发性物质

采用吹扫捕集技术(Purge and Trap technique)对不同十字花科蔬菜中的挥发性成分进行了富集,以气质联用仪(GC／MS)进行鉴定。结果在白菜、羽衣甘蓝、芥蓝、青花菜、芥菜和大白菜中共鉴定出86种挥发性物质,化合物的种类包括醇类、醛类、酮类、酯类、硫醚类等,同时还发现了硫苷降解产物异硫氰酸盐和腈类等化合物。