Control of postpartum anestrous with an intra-vaginal progesterone device plus eCG or calf removal for 120 h in suckled crossbred cows managed in a pasture-based system

To control postpartum anestrus and reduce calving to conception interval, 167 crossbred non-pregnant cows that were 90–130 days postpartum were allotted randomly to one of the following treatments: PH (n = 59), intra-vaginal sponge with 250 mg of medroxyprogesterone acetate (MAP) for 7 days plus 50 mg of MAP and 5 mg 17-β estradiol (17β-E) in the first day of treatment (day −8), 500 UI eCG (day −3) and 1.5 mg 17β-E in 24 h after sponge removal (day 0); CR (n = 57), temporary calf removal for 120 h; CG (n = 51), control group without treatment. Estrus rate differed among treatments (P < 0.01) being greater in PH (78.2%), followed by CR (52.0%) and CG (22.9%). A greater proportion of cows in the PH (80.0%) and CR (54%) groups had ovulations when compared to CG (35.4%). Intervals to first estrus were 13.5 ± 6.3 days, 26.1 ± 6.4 days and 52.5 ± 7.5 days for the PH, CR and CG groups, respectively. First insemination conception was similar in the three groups. Postpartum intervals to first breeding (PFS) and to conception (PCI) were longer in CG than PH and CR groups (P < 0.05; P < 0.01). The PH and CR groups had a similar PFS but PCI was different (P < 0.02). Accumulated pregnancy rate at 30 and 60 but not at 90 days were different (30 days: P < 0.09; P < 0.01; P < 0.09; 60 days: P < 0.06; P < 0.01; P < 0.03) among treatments. After 90 days post-treatment, 9%, 18% and 33% of cows from the PH, CR and CG groups had not conceived. Similarly, 5.4%, 6.0% and 12.5% of cows from the PH, CR and CG groups, respectively, were culled from the herd because of lack of pregnancy after 180 days post treatment. In the group of cows evaluated by ultrasonography, only those cows having larger ovaries and dominant follicles had ovulations. It was concluded that the hormonal treatment was more efficient in inducing a fertile estrus and reducing calving to conception interval followed by the calf removal for 120 h. Each method can be considered as an important tool to reduce the postpartum anestrous period in dual purpose herds when AI is conduct in the tropics.     

中国穿山甲和马来穿山甲头骨量度的测定及比较

全球共有7种穿山甲。本文报道的是中国穿山甲和马来穿山甲的头骨形态学资料,涉及头骨特征描述和一些形态学指标测定。被测定的指标主要有颅全长、基底长、腭长、眶间宽、后头宽、鼻骨长、鼻骨宽、脑颅高、听泡长和下颌长,并且在这两个物种之间进行了比较。结果表明,(1)这两个物种头骨形态十分相似,但马来穿山甲头骨细长,听泡长小于10mm(n=12),鼻骨狭长,前后部宽窄相似,两鼻骨外侧缘内凹或平行,鼻骨宽长之比值小于0 3000(0 2025～0 2811,n=12);而中国穿山甲头骨较粗短,听泡长大于11mm(n=46),鼻骨宽短,后部较前端宽,外侧缘外凸,鼻骨宽长之比值大于0 3000(0 3154～0 5325,n=33)。这些异同之处,可以作为区分这两个物种的依据。(2)中国穿山甲华南亚种与海南亚种头骨各变量之间的差异不显著(P>0 05),用颅全长是否大于83mm来区分这两个亚种不能成立,但海南亚种头骨上颌骨的颧突和鳞骨的颧突通常越过眶颞窝完全相接触,如果不是这样,则在它们之间有一个小的骨质棒状结构将它们连接起来。     

Increased methionine sulfoxide content of apoA-I in type 1 diabetes

Cardiovascular disease is a major cause of morbidity and premature mortality in diabetes. HDL plays an important role in limiting vascular damage by removing cholesterol and cholesteryl ester hydroperoxides from oxidized low density lipoprotein and foam cells. Methionine (Met) residues in apolipoprotein A-I (apoA-I), the major apolipoprotein of HDL, reduce peroxides in HDL lipids, forming methionine sulfoxide [Met(O)]. We examined the extent and sites of Met(O) formation in apoA-I of HDL isolated from plasma of healthy control and type 1 diabetic subjects to assess apoA-I exposure to lipid peroxides and the status of oxidative stress in the vascular compartment in diabetes. Three tryptic peptides of apoA-I contain Met residues: Q(84)-M(86)-K(88), W(108)-M(112)-R(116), and L(144)-M(148)-R(149). These peptides and their Met(O) analogs were identified and quantified by mass spectrometry. Relative to controls, Met(O) formation was significantly increased at all three locations (Met(86), Met(112), and Met(148)) in diabetic patients. The increase in Met(O) in the diabetic group did not correlate with other biomarkers of oxidative stress, such as N(epsilon)-malondialdehyde-lysine or N(epsilon)-(carboxymethyl)lysine, in plasma or lipoproteins. The higher Met(O) content in apoA-I from diabetic patients is consistent with increased levels of lipid peroxidation products in plasma in diabetes. Using the methods developed here, future studies can address the relationship between Met(O) in apoA-I and the risk, development, or progression of the vascular complications of diabetes.     

Types of voltage—dependent calcium channels involved in high potassium depolarization—induced amylase secretion in the exocrine pancreatic tumour cell line AR4—2J

Ca2 channelsandamylasesecreti0ninAR4-2Jce1lsAR4-2Jisacelllineoriginallyderivedfr0matransp1antable,azaserine-inducedmurinetumour[1,2],whichc0ntainssignificantamount0famylaseandotherdiges-tiveenzymes'Thiscelllinecontainsanumberofreceptorsystems:substanceP[3…     

木栓质组成成分、组织化学特性及其生物合成研究进展

木栓质是一种植物次生代谢产物,是以甘油为基础的多聚脂类和多聚酚类物质的聚合物,定位于细胞壁和质膜之间,主要分布在根皮层和茎的次生边界组织中,可以降低细胞水分和营养物质的外流,限制病原体的入侵,阻碍有毒气体向内扩散。近年来,随着人们对果蔬贮藏和植物抗性的关注,对木栓质的研究越来越深入,尤其是代谢相关酶及基因功能研究。该文系统阐述木栓质组织化学、生物合成及其相关酶和基因的研究动态,介绍木栓质的生理功能,总结木栓质组成物质的转运、聚合及其堆积调控等,以期为木栓质的深入研究和开发利用提供参考。     

RACE法克隆甜菜NR基因及生物信息学分析

硝酸还原酶是氮素代谢的关键酶和限速酶,研究硝酸还原酶的功能对提高甜菜的产量具有重要作用。运用RACE法克隆出甜菜的硝酸还原酶基因,并利用生物信息学对甜菜NR进行主要结构分析和功能预测,并使其在拟南芥中表达,观察根对向重性应答过程中的弯曲情况。结果表〖JP2〗明,利用RACE法克隆得到甜菜NR cDNA全长为2 760 bp;甜菜NR为易溶、亲水性强的蛋白;二级结构预测结果显示,甜菜NR为混合型蛋白;甜菜NR含有钼辅因子、细胞色素b5、FAD及NADH结合域,具有跨膜区域,但不含有信号肽;利用拟南芥突变体观察到野生型比突变体的弯曲较快,暗示甜菜的NR基因可能通过调节NO积〖JP〗累参与植物向重性应答。     

紫藤瘤不同溶剂提取部位抗农作物病原真菌活性研究

采用十字交叉法测定紫藤瘤不同溶剂提取物对农作物病原真菌的抑制作用。结果表明:紫藤瘤水提取物在5 mg?mL 1浓度下几乎无抗真菌活性。石油醚、乙酸乙酯和正丁醇提取物在5 mg?mL 1浓度下对辣椒枯萎、小麦赤霉病菌的抑菌率在50%左右,对油菜菌核菌的抑菌效果显著,抑制率高达100%。     

植物光合作用模型参数的温度依存性研究进展

综述了植物光合作用与温度响应模型研究的进展,围绕光合作用生化模型的4个主要参数：胞间CO₂浓度、RuBP最大碳同化速率(V_{c max})的活化能、RuBP最大再生速率(J_max)的活化能和J_max/V_{c max},讨论了影响光合作用 温度响应曲线的内在机理.随着生长温度的升高,所有物种的V_{c max}活化能均呈增加趋势,而其他参数的变化因物种不同而存在明显差异,说明V_{c max}的活化能可能是决定光合作用温度依存性的首要参数.最后分析了研究中存在的问题并提出研究展望,认为应整合叶片与群落水平的光合作用模型,从叶面积、太阳辐射、冠层结构、冠层小气候和光合能力等方面研究植物群落对全球变化的响应机理.这对于人们理解和准确估算植物生长、群落碳收支和生态系统初级生产力具有重要意义.