不同方法从小鼠胚胎干细胞分化拟胚体

建立简便有效的胚胎干细胞体外分化研究中制备拟胚体的方法。本实验以3种方法形成拟胚体：滋养层过生长法、悬浮法和胶原酶处理法，并与传统的悬滴法进行了比较。在不同的分化培养体系中以最终分化出搏动的心肌细胞评价形成有分化发育能力的拟胚体的效率。以RT—PCR检测了拟胚体和心肌细胞形成中基因的表达。结果表明，4种方法分化出搏动心肌细胞的比例不同。滋养层过生长法形成拟胚体的比例接近悬滴法．而悬浮法和胶原酶处理形成拟胚体的比例显著低于滋养层过生长法和悬滴法。形态学研究显示，拟胚体发育经历了简单拟胚体阶段到囊状拟胚体或成熟拟胚体。在拟胚体成熟过程中特异性胚层分化发育分子标记HNF-4、Bmp-4与Otx-2表达上调，与心肌细胞分化相关的基因α—MHC、β-MHC、GATA-4及Nkx2．5同样表达上调。表明不同途径可获得不同比例的有发育能力的拟胚体，在体外分化研究中滋养层过生长法则是简便有效的获得正常发育拟胚体的方法。     

ULTRASONOGRAPHIC FEATURES OF GRASS AWNS IN THE URINARY BLADDER

Grass awns are a common cause of foreign body disease in animals, but little is known about their presence in the lower urinary tract. The ultrasonographic features of grass awns in vivo and in vitro have been described in detail. The purpose of this report is to describe the clinical and sonographic features of grass awns in the urinary bladder of dogs and cats. Three male Yorkshire terriers (one of which was examined twice) and one female domestic short‐haired cat were evaluated for signs of lower urinary tract disease, and an intravesicular grass awn was suspected based on ultrasound examination. The grass awn appeared ultrasonographically as a bladder stone (n=1) or a linear hyperechoic structure (n=4) with or without acoustic shadowing that was easy to identify due to contrast with surrounding urine. The presence of a grass awn within the urinary bladder was confirmed during exploratory surgery. In all patients, the route of entry of the grass awn was thought to have been retrograde migration from the urethral opening. The ultrasonographic appearance of grass awns in the bladder is consistent with that in other tissues.     

Seed germination and tissue culture of Cymbidium giganteum Wall. ex Lindl.

Efficient protocols were established for in vitro seed germination, neo-formation of secondary (2°) protocorms from primary (1°) protocorms and multiple shoot buds and protocorm-like body (PLB) induction from pseudo-stem segments of in vitro-raised seedlings of Cymbidium giganteum. Four nutrient media, namely Murashige and Skoog (MS), Phytamax (PM), Mitra et al. (M), and Knudson ‘C’ (KC) were evaluated for seed germination and early protocorm development. In addition, the effects of peptone, activated charcoal (AC) and two plant growth regulators [6-benzylaminopurine (BAP) and 2,4-dichlorophenoxyacetic acid (2,4-D)] were also studied. Both M and PM supplemented with 2.0 g l⁻¹ peptone or 1.0 mg l⁻¹ BAP resulted in ∼100% seed germination. Media supplemented with 2.0 g l⁻¹ AC could effectively induce large protocorms (1.6 ± 0.1 mm in diameter). Neo-formation of 2° protocorms from 1° protocorms was achieved in liquid and agar-solidified PM medium fortified with different concentrations and combinations of auxins (α-naphthalene acetic acid (NAA) and 2,4-D) and cytokinins [BAP and kinetin (KN)]. The highest number of 2° protocorms was obtained in liquid medium (10.7 ± 0.9/1° protocorm) supplemented with 2.0 mg l⁻¹ BAP + 1.0 mg l⁻¹ NAA. Although protocorms proliferated profusely in liquid medium, these did not develop further unless transferred to agar-solidified medium within 6–8 weeks. Multiple shoot buds and PLBs were induced from pseudo-stem segments on agar-solidified PM medium fortified with different concentrations and combinations of BAP and NAA and the maximum number of PLBs (6.00 ± 0.20) was recorded when BAP and NAA were applied at 2.0 mg l⁻¹ each. A solid root system was induced from PLBs and shoot buds when these were transferred to half-strength PM or M media fortified with 0.5 mg l⁻¹ indole-3-acetic acid. Well-rooted plants were transferred to the greenhouse with 95% survival.     

瘦西湖不同临水景观空气负离子密度比较

测定扬州瘦西湖景区4种类型水体环境中的空气负离子密度,并以单极系数和安倍空气离子评价系数为标准对扬州瘦西湖景区空气质量进行评价。结果表明:空气负离子密度依次为石壁流淙(瀑水)卷石洞天(跌水)钓鱼台(湖水)凫庄(湖水);空气质量均达到清洁水平,人体舒适度较高,其中,动态水域的空气质量达到A级(极清洁水平)、静态水域的空气质量达到B级(一般清洁水平)。测试数据经SPSS方差分析,4种水体环境中的空气负离子密度差异性显著。     

蝴蝶兰原球茎的增殖研究与解剖学观察

蝴蝶兰是名贵花卉,市场需求量大,工厂生产大多通过组织培养无性繁殖来达到扩增的目的。本研究以蝴蝶兰（Phalaenopsis）的原球茎（Protocorm-like body,以下简称PLB）为外植体在VW + 3.0 mg/L 6-BA+ 0.2 mg/L NAA+ 20 g/L 蔗糖+ 16 g/L琼脂+ 1 g/L活性炭中分别添加不同浓度（10%、15%、20%）的有机物（椰乳、椰汁、马铃薯汁、香蕉泥、水解酪蛋白）进行培养,比较不同浓度的有机添加物对蝴蝶兰PLB增殖的影响。结果表明：5种有机添加物中,对蝴蝶兰PLB增殖效果总体影响由好至差依次为椰乳、椰汁、马铃薯汁、香蕉泥、水解酪蛋白。椰乳的最佳增殖浓度是15%,椰汁的是20%,马铃薯汁的是10%,香蕉泥的是15%,而水解酪蛋白的10%、15%、20%这3个浓度都偏高,抑制了PLB的增殖。对蝴蝶兰初生、次生各阶段PLB和由PLB所诱导分化的叶芽进行了切片观察,结果表明初生PLB的周边细胞排列紧密,中间细胞则稀疏,没有规则;次生PLB的细胞则大小比较均一,次生PLB发生于初生PLB的下半部,叶芽则发生在球茎的上半部区域,在初生PLB中还存在肾型的气孔和未知功能的棒状结构。     

Effects of intracerebroventricular treatment with oleate or octanoate on fatty acid metabolism in Brockmann bodies and liver of rainbow trout

Intracerebroventricular (ICV) treatment with oleate or octanoate induced in Brockmann bodies (BB) and liver of rainbow trout changes in several parameters related to fatty acid (FA) sensing through FA metabolism, FA transport through FA translocase (FAT/CD36) and mitochondrial activity. Changes observed in BB were completely different to those observed in previous studies after treatment with the same FA either intraperitoneal (IP) or in vitro. Therefore, FA sensing in BB is apparently direct and not related to previous FA sensing in hypothalamus, but it could be influenced by changes in the levels of peripheral hormones like insulin. In contrast, results obtained after ICV treatment with FA in liver were comparable to those observed after IP treatment but different to those observed after in vitro treatment. Therefore, FA sensing in liver is apparently indirect and be the consequence of previous hypothalamic FA sensing followed by vagal and/or sympathetic outflow.     

B超技术对犬胃内不同性质异物的诊断价值研究

[目的]探讨B超技术对犬胃内不同密度异物的诊断价值。[方法]利用B超技术对犬胃内9种异物进行超声检查,并对犬胃内不同大小、形状、密度异物的诊断效果进行了归类和比较。[结果]B超对高、中和低密度异物都有一定的诊断价值,但对异物的性质不能辨别。[结论]该研究可为相关病例的临床诊断提供科学方法。     

顶空固相微萃取结合气相色谱-质谱法分析柱状田头菇挥发性成分

以柱状田头菇(Agrocybe cylindracea)子实体干品及其经蒸馏得到的的馏分为萃取样品,采用顶空固相微萃取法(headspace solid-phase micro-extraction,HS-SPME)进行挥发性成分提取,气相色谱-质谱法(gaschromatography-mass spectrometry,GC-MS)进行定性定量分析,综合评价柱状田头菇子实体挥发性成分。试验共检测到99种挥发性成分,其中干品样品59种,主要为酸类;馏分中55种,主要为醛类和酮类;干品和馏分中检测到相同组分有15种。     

AAS测定巨大口蘑子实体及生长土壤微量元素

本文所述用原子吸收法测定巨大口蘑子实体及生长土壤微量元素，其结果是红河菌株和思茅菌株子实体的微量元素富集量有较大差异，生长土壤微量元素富集量与子实体中的微量元素富集量都有密切关系。该方法操作简便、分析快速，测定结果令人满意。     

CONTRAST RADIOGRAPHY OF THE GASTROINTESTINAL TRACT IN SEA TURTLES

Intestinal obstruction by radiolucent foreign bodies is common in sea turtles. The absence of clinical signs and the extended fasting periods in these animals means that intestinal obstructions may not be diagnosed early. Digestive tract radiographic contrast procedures were performed to evaluate the gastrointestinal transit time and intestinal obstructions in loggerhead sea turtles. Barium sulfate and nonionic iodinate contrast medium were used for radiographic contrast procedures. Contrast medium was administered via a gastric tube or into the colon. These procedures are often necessary and are useful to document intestinal obstruction and foreign objects. The diagnostic procedures were not easily performed in some turtles, but often they were adequate for the diagnosis.