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31.
建立复方磺胺间甲氧嘧啶钠可溶性粉中磺胺间甲氧嘧啶钠(以磺胺间甲氧嘧啶计)和甲氧苄啶含量的HPLC检测方法,采用Inertsil C18色谱柱(4.6mm×250mm,5μm),以乙腈:0.017mol/L磷酸液(20:80)(按1‰的比例加入三乙胺)为流动相,流速为1mL/min,检测波长为230nm。在该色谱条件下,两种药物分离很好,磺胺间甲氧嘧啶在24.89~248.9μg/mL之间,甲氧苄啶在5~50μg/mL之间,线性良好(r〉0.99999),添加回收率在97.46%~100.45%之间。该方法快速简便,准确可靠,能够满足实际样品的检测要求。 相似文献
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芸薹素内酯和复硝酚钠对茭白生长发育和产量的影响 总被引:1,自引:0,他引:1
通过研究芸薹素内酯和复硝酚钠两种植物生长调节剂对茭白生长发育和产量的影响。研究结果表明,喷施1.8%复硝酚钠水剂5.94mgm(有效成分含量,下同)、0.04%芸薹素内酯水剂0.07mg/L以及1.8%复硝酚钠水剂与0.04%芸薹素内酯水剂等体积混配液1.84mg/L等三种处理均能使茭白结茭时间提早4-5d,茭白的有效苗数、结茭率和产量显著提高。建议在茭白孕茭前15~30d喷施1次,隔7d后再喷1次较好。 相似文献
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本研究拟通过分析丁酸钠对脂多糖(LPS)诱导的奶牛乳腺上皮细胞系(MAC-T细胞)炎性损伤的修复作用,进一步从体外角度阐述丁酸钠对奶牛乳腺健康的调控机制。在MAC-T细胞中添加不同浓度(0、1、10、100、1 000、10 000 ng/mL)的LPS,检测细胞活力,以确定LPS的适宜浓度,建立细胞氧化损伤模型;并进一步在MAC-T细胞中添加不同浓度(0、2、4、8、16、32μmol/L)的丁酸钠,检测细胞凋亡率,以确定丁酸钠的适宜浓度。最终选用1 000 ng/mL LPS和16μmol/L丁酸钠用于本试验。试验分为3组,分别为对照组、LPS处理组和LPS+丁酸钠处理组,分别对其细胞形态、氧化应激指标及凋亡蛋白mRNA表达水平进行检测。结果表明:1)对照组MAC-T细胞呈扁平的无规则形态,贴壁状态良好;而LPS处理组MAC-T细胞核固缩、破裂,并出现大面积死亡脱落现象;LPS+丁酸钠处理组MAC-T细胞边缘清楚,胞内颗粒较少,死亡脱落现象明显减少。2)与对照组相比,LPS处理组MAC-T细胞中超氧化物歧化酶(SOD)活性和总抗氧化力(T-AOC)显著降低(P<0.05),丙... 相似文献
36.
The aim of this series of studies was to evaluate two possible feeding strategies as methods for reducing the risk of calcium oxalate (CaOx) formation in two breeds of healthy dog. The studies compared the effect of dietary moisture (Study 1) and dietary sodium (Na), (Study 2) on urine composition of labrador retrievers (LR) and miniature schnauzers (MS). A nutritionally complete dry dog food was fed to 16 dogs (eight LR, eight MS; Study 1) and 15 dogs (seven LR, eight MS; Study 2) for 24 days (Study 1), or 36 days (Study 2). The dogs were fed the diet alone (7% moisture, 0.06 g Na/100 kcal), or supplemented with deionised water to 73% moisture (Study 1), or dietary Na, to deliver 0.20 or 0.30 g Na per 100 kcal (Study 2). Urine pH, volume, specific gravity, and concentrations of 12 analytes were measured for each dog. Urinary relative supersaturations (RSS) with CaOx were calculated from these values. The effects of supplemental Na or water were established using t tests (Study 1) or analysis of variance, and multiple range tests (least significant difference) (Study 2); P<0.05 was considered significant. Increasing dietary moisture significantly increased total moisture intake (P=0.001), and reduced urine specific gravity (P=0.003), urinary oxalate concentration (P=0.04), and CaOx relative supersaturation (P=0.04) in the MS. Urinary parameters remained unchanged in the LR, indicating that feeding a high moisture diet may reduce the risk of CaOx formation in high-risk breeds. Increasing dietary Na led to production of urine with a significantly lower CaOx RSS in both breeds, indicating that sodium supplementation to dry diet formats may reduce the risk of CaOx formation. These feeding strategies should be considered when evaluating methods for preventing CaOx formation within high-risk groups. 相似文献
37.
D.?SivakumarEmail author N.?K.?Hewarathgamagae R.?S.?Wilson Wijeratnam R.?L.?C.?Wijesundera 《Phytoparasitica》2002,30(5):486-492
Colletotrichum gloeosporioides is the causal organism of anthracnose inCarica papaya L. (papaya, papaw). The effect of ammonium carbonate (3%) or sodium bicarbonate (2%) in aqueous solution or when incorporated
into a wax formulation on anthracnose severity in inoculated or naturally infected fruits was examined. Both salts had significant
effects, but that of ammonium carbonate was greater than that of sodium bicarbonate in controlling anthracnose. Ammonium carbonate
(3%) incorporated into the wax formulation effectively reduced anthracnose incidence by 70% in naturally infected papaya and
extended the storage life by maintaining the firmness, color and overall quality of the fruit in low temperature storage (13.5°C)
and 95% r.h. for 21 days followed by 2 days under marketing conditions. The mode of action of ammonium carbonate on the control
of anthroacnose appears to bevia complete inhibition of radial mycelial growth and conidia germination.
http://www.phytoparasitica.org posting Aug. 14, 2002. 相似文献
38.
家兔亚硒酸中毒的病理形态学研究 总被引:1,自引:0,他引:1
给家兔分别肌肉注射不同剂量的亚硒酸钠,历时入周,复制出亚急性硒中毒的动物模型。病理形态学变化为:家兔的生长受到明显抑制,肝,肾,心,脾等组织器官损害严重如肝实质细胞变性,坏死;肾实质退行病变;心肌纤维变性,充血,肺淤血,水肿:脾萎缩,淋巴细胞坏死,肝,肾,心细胞内线粒高度肿胀,嵴减少,断裂或消失成空泡。 相似文献
39.
The Mount Lofty Ranges koala (Phascolarctos cinereus) population in South Australia has a high prevalence of the renal disease oxalate nephrosis, for which an underlying genetic cause is suspected. South Australian koalas primarily originate from those in French Island, Victoria; however, oxalate nephrosis has not previously been reported in Victorian koalas. Examination of kidney tissue sections from 63 koalas across Victoria found that nine koalas were affected by oxalate nephrosis (14.3%). These included 2/5 koalas from French Island (40%), 4/14 koalas from the western regions (29%), 2/11 Raymond Island koalas (18%), and 1/13 Cape Otway koalas (8%). There were no cases of oxalate nephrosis identified in the Strzelecki koalas (n = 12). These findings suggest that oxalate nephrosis occurs in koalas from French Island and populations that have received significant influx of koalas from French Island, but not in the Strzelecki region, which has little to no French Island input. This lends support to the theory that an inherited abnormality of oxalate metabolism could underlie the high prevalence of oxalate nephrosis in the Mount Lofty Ranges koala population, and molecular investigations are currently underway to investigate a genetic cause. 相似文献
40.