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991.
This experiment was aimed to study the antigenicity of prokaryotic expression of the N gene fragment of porcine epidemic diarrhea virus (PEDV),and lay a foundation for establishing an indirect ELISA method of PEDV.The N gene segment was amplified by RT-PCR,then the recombinant plasmid with the vector pET-30a(+) was constructed,which was induced by 0.5 mmol/L IPTG at 37 ℃ for 4 h.Furthermore,the expressed product was analyzed by SDS-PAGE and Western blotting.Sequencing results proved that recombinant plasmid was correctly constructed.The result showed that the PEDV polyclonal antibody could specifically bind to PEDV N protein,which indicated that the recombinant fusion protein had excellent immunogenicity.A prokaryotic expression vector for the fragment of N protein was successfully constructed in this study,which laid a foundation for the development of diagnosis of PEDV.  相似文献   
992.
This study aimed to describe the gross anatomy of the ventral rami of the thoracic spinal nerves in capuchin monkey (Sapajus apella) and compare with humans and other primate species. Eight specimens, prepared in 10% formalin solution and dissected following routine standard techniques, were used. The animals presented 13–14 pairs of thoracic spinal nerves emerging from the intervertebral foramen and divided into dorsal and ventral rami. The ventral rami of the first 12 or 13 pairs represented intercostal nerves and the latter referred to the subcostal nerve. The intercostal and subcostal nerves gave off muscular and cutaneous branches (lateral and ventral), which promote innervation of muscles and skin associated with the chest and abdominal wall. Atypical anatomy was verified for the 1st, 2nd and 7th to 13th intercostal nerves as well as for the subcostal nerve. The morphological characteristics were similar to those observed in humans and some non‐human primates, especially in the absence of collateral branches.  相似文献   
993.
过瘤胃氯化胆碱在泌乳奶牛上的应用   总被引:4,自引:3,他引:1  
将14头荷斯坦奶牛完全随机分为2组,每组7头。试验组从围产前期开始至产后1个月内每天每头饲喂10 g过瘤胃氯化胆碱,测定所有供试牛产后第1个泌乳月内日均产奶量;同时分别在产前1周、产后24 h、产后1、2、3、4周共6个时间点采血,测定血清中血糖、D3 羟丁酸、血脂(甘油三酯、总胆固醇, 包括高密、低密、极低密)、谷丙转氨酶、谷草转氨酶的含量。结果表明,与对照组相比,饲喂过瘤胃氯化胆碱的奶牛产后第1个月内日均产奶量比对照组提高1.7%(P>0.05);围产期及泌乳初期血糖能维持在相对稳定的水平;D3 羟丁酸含量降低(P>0.05),血脂、谷丙转氨酶、谷草转氨酶均无显著差异(P>0.05)。因此,围产期饲喂过瘤胃氯化胆碱能缓解奶牛产后能量负平衡状态,预防酮病,帮助奶牛快速恢复健康,提前进入产奶高峰期,提高牛场经济效益。  相似文献   
994.
研究了不同施肥时期及施肥量对草地早熟禾生长发育特性的影响.研究表明:返青期加强施肥有利于草地早熟禾的生长,同时,可显著提高植株密度以及干物质的积累量.  相似文献   
995.
AIM: To observe effect of rhynchophylline (Rhy) on mortality and organ injury in endotoxemic mice and further investigate the mechanisms of its actions. METHODS: Male mice were randomly assigned into control, LPS, Rhy +LPS and Rhy group, and injected subcutaneously with normal saline (0.05 mL/10 g), or rhynchophylline once a day for 3 d, 1 h after subcutaneously treatment on day 3, LPS (20 mg/kg) or normal saline was injected intraperitoneally. Survival rate was recorded every 12 h for 6 d. In another experiment, 12 h after LPS injection, the left lung and intestine tissue sections were prepared for histological analysis and the right lung were used to determine the ratio of wet to dry lung tissue weight (W/D),the serum was collected to detect the concentrations of alanine aminotransferase(ALT), aspartate aminotransferase (AST ), bloodureanitrogen (BUN) and creatinine (Cr). In addition, the concentrations of tumor necrosis factor-α (TNF-α), interleukin-1β(IL-1β) and interleukin-10 (IL-10) in serum at 2 h after LPS challenge were detected by enzyme-linked immunosorbent assay. The concentration of NO in serum at 8 h was detected by enzymic method. The effect of Rhy on survival rate of mice subjected to cecal ligation and puncture (CLP) was also observed. RESULTS: Mortality of mice challenged with LPS alone was higher significantly than that in control at 24 h after LPS challenge, pretreated with Rhy at a dose of 8 or 16 mg/kg increased markedly the survival rate of LPS-challenged mice. However, Rhy at a dose of 8 mg/kg significantly increased mortality of mice subjected to CLP. In the histological analysis, severe inflammation was observed both in the lung and intestine tissues in the LPS group. LPS elevated lung W/D, the levels of ALT, AST, BUN, Cr, TNF-α, IL-1β, IL-10 and NO in serum. Pretreatment with Rhy had no obvious improvement in the lung and intestine tissue injury, and no significant depression in the lung W/D and the serum levels of ALT, AST, BUN, Cr, IL-1β, IL-10 and NO, but decreased the level of TNF-α in serum significantly in LPS -treated mice. CONCLUSION: Pretreatment with Rhy reduces the mortality in endotoxemic mice, but not decrease the mortality of mice challenged with CLP, at least in part, through inhibiting the synthesis and secretion of TNF-α.  相似文献   
996.
AIM: To study the effect of renal epoxyeicosatrienoic acids (EETs)on juvenile rats with obesity related hypertension induced by high fat diet.METHODS: Sprague-Dawley male rats were fed with high fat diet from 3-week old. The changes of weight and sBP between the rats of high fat diet and normal diet were compared. EETs activity was analyzed with RP HPLC and Western blotting in different parts of kidney.RESULTS: Weight and sBP increased in high fat diet group at the eighth and eleventh weeks [(328±23)g vs (273.0±21.0)g, (153.0±8.6)mmHg vs (134.0±7.7)mmHg, P<0.05]. No significant change of the EETs activity of renal microvessels between two groups was observed. The EETs activity in cortex and papilla decreased in high fat diet group compared with that in normal diet group [(75.4±9.2)nmol·g-1·min-1 vs (138.1±10.3)nmol·g-1·min-1, (55.8±6.2)nmol·g-1·min-1 vs (121.6±11.3)nmol·g-1·min-1, P<0.05], and this was confirmed by Western blotting.CONCLUSION: These results demonstrate that juvenile rats with obesity related hypertension induced by high fat diet might be related to the downregulation of EETs activity in cortex and papilla.  相似文献   
997.
Beef cows’ milk yield is typically determined by measuring milk yield once daily and then doubling this value to estimate daily production. However, it is not known whether this is accurate. Thus, we aimed to determine the association between morning and afternoon milk yield in grazing Nellore cows. Eighty Nellore cows were used, with initial weight of 516.0?±?1.0 kg. The experiment was a completely randomized factorial scheme, with 20 replications and four treatments (i.e., +?or ??pre-partum supplementation in combination with +?or ??post-partum supplementation): PRMM—1 kg of supplement/cow/day for 90 days pre-partum; MMPS—1 kg of supplement/cow/day for 90 days post-partum; PRPS—1 kg of supplement/cow/day for 90 days pre-partum and 90 days post-partum; and MM—only mineral mix ad libitum during pre- and post-partum. Milk was sampled on days 45, 135, and 225 post-partum (early, middle, and late lactation, respectively). No effects were observed of pre- and post-partum supplementation on milk yield (P?>?0.05). The afternoon/morning proportion of 0.45 in the early third of lactation was higher than other stages, which had a proportion of 0.41 (P?<?0.05). Post-partum supplementation increased milk protein in the morning and afternoon milking (P?<?0.05). There was also no effect of pre- and post-partum supplementation on afternoon-morning proportion other milk components (P?>?0.05). We conclude that estimating daily milk production of grazing beef cattle by multiplying a once daily milking amount times two is not accurate. Under the conditions of this study, proportion of total daily production represented by the ratio of afternoon/morning milking was 0.45 in early lactation (first third) and 0.41 in mid- and late lactation.  相似文献   
998.
999.

Objective

To describe a successfully managed case of polyneuropathy and respiratory failure secondary to presumed monensin intoxication.

Case Summary

A 9‐month‐old Australian Shepherd was evaluated for progressive generalized weakness and respiratory distress. Several days preceding presentation, the dog was seen playing with a monensin capsule, and had free access to a barn where the product was stored and where chewed capsules were subsequently found. The dog was presented with flaccid tetraparesis, hyperthermia, and severe respiratory distress. Bloodwork and urinalysis revealed marked increase in serum creatine kinase concentration and presumed myoglobinuria. Cardiac troponin I level was markedly increased. Management included mechanical ventilation for 5 days, fluid‐therapy, active cooling, antimicrobial therapy, analgesia, gastroprotectants, antiemetics, enteral feedings, continuous nursing care, and physiotherapy. Intravenous lipid rescue therapy was administered with lack of improvement in respiratory function and muscle strength. The patient completely recovered and was discharged after 12 days of hospitalization.

New or Unique Information Provided

Monensin intoxication should be considered in the differential diagnosis of acute polyneuromyopathy and respiratory failure in dogs with access to this compound. Respiratory failure secondary to monensin intoxication does not necessarily carry a poor prognosis if mechanical ventilation can be provided as a bridge until return of respiratory function is achieved.  相似文献   
1000.
贝类养殖和育种实践中,贝壳生长纹宽窄是衡量贝类生长速度的重要观测指标,臀角放射肋为呈现生长纹最宽的部位,为了探究臀角放射肋长作为典型生长性状的可行性,本研究分析了1~3龄三角帆蚌臀角放射肋长(X1)与壳长(X2)、壳高(X3)、全高(X4)、壳宽(X5)、活体质量(Y1)、软体质量(Y2)、壳质量(Y3)的相关性,并进行体尺性状对体质量性状(活体质量、软体质量和壳质量)的通径分析。相关性分析结果表明,1~3龄的三角帆蚌臀角放射肋长与体质量均呈极显著正相关(P<0.01)。1龄、2龄三角帆蚌壳长与活体质量的相关系数最高,而3龄三角帆蚌的臀角放射肋长与活体质量的相关性最高,且臀角放射肋长与体质量性状的相关系数均随年龄的增加呈增长趋势。通径分析和多元回归分析表明,影响1~3龄的三角帆蚌活体质量的主要因子为臀角放射肋长、壳长、壳宽,影响3龄的三角帆蚌软体质量的主要因子为壳长、壳宽,影响1龄、2龄的三角帆蚌壳质量的主要因子为壳长、壳宽,影响3龄的三角帆蚌壳质量的主要因子为臀角放射肋长、壳长、壳宽。综上所述,臀角放射肋长可与壳长、壳宽性状一起作为三角帆蚌新的典型生长性状,用以表示三角帆蚌生长速度。  相似文献   
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