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61.
刘宗才  白小玲  焦铸锦 《安徽农业科学》2013,(20):8817-8818,8823
通过半薄切片,研究了比克氏棉休眠种子内色素腺体的分布、发育状态。根据色素腺体的发育状态,分为不具分泌腔的色素腺体即"色素腺体原"以及具有分泌腔的色素腺体2种类型。不具分泌腔的色素腺体主要位于分化程度较低的胚轴、子叶顶端等组织部位。具有分泌腔的色素腺体主要分布在靠近子叶基部分化程度较高的组织部位。该研究验证了比克氏棉休眠种子内子叶和胚轴含有色素腺体,并首次发现子叶内部分色素腺体已发育出分泌腔。  相似文献   
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蜱的免疫预防是目前国内外研究的热点,以抗血清为探针筛选cDNA表达文库是获取功能抗原基因的有效的方法之一,为了获得抗长角血蜱免疫原基因,用兔抗长角血蜱血清和兔抗长角血蜱唾液腺蛋白血清对长角血蜱雌蜱唾液腺cDNA表达文库进行了免疫筛选,经过两轮筛选共获得34个阳性克隆,所得阳性噬菌体转染宿主菌BM25.8使之亚克隆为重组质粒,用此质粒转化宿主菌JM109并进行序列测定和生物信息学分析.结果表明:在长角血蜱雌蜱唾液腺cDNA表达文库中获得26个长角血蜱免疫相关cDNA序列,其编码蛋白与长角血蜱HL35、黏附素hlim3假定蛋白、热休克蛋白、NADH脱氢酶、钙网蛋白以及杂色花蜱和肩突硬蜱的二硫异构酶等具有同源性.所获阳性克隆为长角血蜱保护性抗原基因的筛选奠定了基础.  相似文献   
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Reasons for performing study: Fillies completely devoid of endometrial glands (uterine gland knockout; UGKO) would make ideal experimental models in which to study the role of endometrial histotroph in embryogenesis and early fetal development in the mare. Hypothesis: Administration of a synthetic progestagen plus oestrogen to newborn filly foals and, thereafter, at regular intervals to age 6 months, would permanently suppress endometrial gland development. Methods: Nine half‐sister Thoroughbred filly foals were treated, in 3 groups, with: A) the weakly active progestagen, norgestomet, administered from birth to age 6 months, in subcutaneous implant form plus oestradiol valerate and norgestomet i.m. at fortnightly intervals; B) the strongly active oral progestagen, altrenogest, administered daily from birth to age 6 months plus fortnightly injections of oestradiol valerate and norgestomet; C) nothing (untreated controls). Endometrial biopsies were recovered from all fillies at ages 6 months and 2 years to assess the degree of endometrial gland morphogenesis and to determine immunohistochemically the presence or absence of oestrogen and progesterone receptors in the endometrial tissues. Results: Groups B and C showed no endometrial gland development, whereas Group A fillies showed a high degree of endometrial gland development, plus strong staining for both oestrogen and progesterone receptors at age 6 months. All 9 fillies showed full normal endometrial gland morphogenesis, development and function at age 2 years. Conclusions and relevance: While the administration of a strongly active progestagen over‐rode the actions of the concomitantly administered oestrogen and suppressed endometrial gland development during the period of administration, treatment with oestradiol valerate together with a weakly active progestagen, stimulated precocious endometrial gland development. Neither steroid was able to create the desired UGKO experimental model and all fillies showed normal endometrial gland development and fertility after puberty. Hence, ovarian oestrogen, not progesterone, appears to be the basic stimulus for endometrial gland morphogenesis in the horse.  相似文献   
66.
A 9-year-old neutered male domestic shorthair cat was presented because of coughing, dysphagia, and prostration. Examination revealed firm bilateral anterocervical swellings extensively adhered to the surrounding tissues. Anisocoria with left-side miosis was also evident. X-ray and ultrasound examinations along with a fine-needle aspiration biopsy were performed. Slides were stained with May-Grünwald Giemsa, and a diagnosis of salivary gland carcinoma was made. At surgery, the tumor was found to involve both submandibular salivary glands as well as adjacent lymph nodes and surrounding tissues. The cat was euthanized and necropsy was performed. The majority of tissues and organs examined histologically, including mandibular and retropharyngeal lymph nodes, soft palate, laryngopharynx and lungs, contained neoplastic cells whose appearance was consistent with adenocarcinoma. Bilateral salivary adenocarcinoma has not previously been reported in cats, and extensive metastases are rare.  相似文献   
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The role of nitrogenous compounds in the pest‐host interaction of Aradus cinnamomeus and Pinus sylvestris was studied by analysing free amino acids and related compounds in the insects and the cambial layer of Scots pine. About 35 different compounds were identified by means of thin‐layer and automatic ion‐exchange chromatography. The total content of amino acids in the insects was ca. 0.86% of the fresh weight (65 μmoles/g), ca. 0.075% (7.2 μmoles/g) in the young phloem layer of Scots pine, and ca. 0.078% (6.8 μmoles/g) in the young xylem layer. The most abundant free amino acids in the insects were proline and glutamine, followed by alanine, glutamic acid, taurine, histidine, arginine, and lysine. The amino acid composition was similar in males and females, and almost identical in brachypterous and macropterous females. The concentration of glutamic acid was low in the hemolymph but high in the salivary glands and other tissues. In other respects the amino acid composition of the salivary glands resembled that of the whole insect. No distinctly phytotoxic compounds were identified in the insects. The predominant amino compounds in the cambial layer of the pine saplings were γ‐aminobutyric acid, glutamine, ethanolamine, serine and alanine. The amino acid composition was similar in extracts of phloem and xylem. The bulk of the alcohol‐soluble compounds in the pine cambial layer were carbohydrates (ca. 3.5% of fresh weight).  相似文献   
69.
涎流冰是林区公路的常见病害,它的形成与很多因素有关,由于各种因素的不同而产生了不同类型、规模的涎流冰,该文探讨了涎流冰的形成条件、类型特征及几种常见的治理方法。  相似文献   
70.
为解决养猪生产中传统发情鉴定法工作量大、准确率低等问题,本研究以经产大白母猪为研究对象,将发情周期分为发情前3天(PE),发情期(E)和发情后3天(AE)3个阶段,分别收集口腔中唾液,提取唾液蛋白,使用Lable-free定量蛋白组学技术对3个阶段的唾液蛋白组进行质谱检测,并通过蛋白质组学定性定量软件Maxquant进...  相似文献   
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