不同固定液及保存温度、时间对小鼠组织DNA的影响

比较10％甲醛、95％乙醇、Saccomanno3种固定液及不同保存温度、保存时间对小鼠肝、肺组织DNA的影响。取材后将标本分为无固定液组、甲醛组、乙醇组和Saccomanno组,不同温度保存至一定时间后提取DNA进行比较。结果无固定液时,保存3d后,室温且与低温组差别不大。甲醛固定时,对不同保存温度、时间、不同组织的DNA影响不同。乙醇、Saccomanno法室温放置1个月后DNA仍保存良好。短时间室温保存对DNA影响不大。10％甲醛使DNA降解,95％乙醇、Saccomanno法固定则可以保护DNA的完整性。     

变色素2R水溶液显示神经髓鞘的新方法

本文应用变色素 2R(Chromotrope 2R)显示神经髓鞘的新方法,将神经髓鞘染成红色,形态清晰,颜色鲜艳,操作简便,易于掌握,是显示神经髓鞘较为优良的方法,为神经组织的病理诊断和研究提供了新的技术方法.标本来源:尸检脑组织、脊髓和周围神经组织,经10%甲醛固定,石蜡包埋,切片5μm.试剂的配制:①变色素2R染液:变色素2R(北京化工厂)0.5g,磷钨酸0.6g,冰醋酸1.0g,蒸馏水加至100ml.放置4℃冰箱长期保存,用前回温.②0.2%冰醋酸水溶液:冰醋酸0.2ml,蒸馏水加到100ml.染色步骤:     

洗发液中甲醛的测定和比较

甲醛溶液通常被用作防腐剂。但它能使细胞的正常生理活动收到抑制,所以也是一种原生质毒药。洗发液其中添加了一种叫做DMDM Hydantoin的物质,作用是防腐,它会分解反生少量甲醛.使用时的安全添加浓度是0.2%。洗发液中的甲醛超标会对人们的身体造成严重伤害。使用乙酰丙酮作为显色剂的分光光度法[1]测定洗发液中的甲醛含量优点是受干扰小,操作简单,重复性好,但是光吸收过程显色温度和反应时间都对实验结果稍有影响[2]。     

紫外分光光度法测定珍珠菜中总黄酮含量

目的:建立珍珠菜提取液中总黄酮的含量测定方法。方法:采用紫外分光光度法,通过紫外可见扫描确定最大吸收波长,以芦丁为对照品制定标准曲线,并进行样品溶液稳定性试验和方法回收率与精密度试验。结果:最大吸收波长为405 nm,标准曲线线性范围为4.014-32.112μg/mL,r=0.999 9。样品液经A l3 络合后在0.5-2.5h内稳定性较好,平均加样回收率为102.00%±1.64%,RSD为1.61%,日内、日间精密度RSD小于2%,符合要求。结论:该方法简单方便、准确可靠,可以用来测定珍珠菜中总黄酮的含量。     

不同叶色三叶海棠叶片成色色素分析

三叶海棠秋季叶色丰富,观赏价值良好。该研究以三叶海棠叶色差异明显的绿色、黄色、红色系的叶片为材料,利用紫外—可见分光光度法、高效液相色谱法对色素进行了定性定量检测,并分析了叶色变化的原因。结果表明:三叶海棠叶片中的色素主要有叶绿素、类胡萝卜素和花青苷,其中花青苷主要是矢车菊素半乳糖苷。绿色系叶片中的叶绿素含量与所占比例显著高于红色和黄色系叶片,而花色素苷和类胡萝卜素所占比例均最小;红色系叶片中的花青苷含量高于其它色系的叶片,花青苷所占比例高于叶绿素与类胡萝卜素所占比例;黄色系叶片中类胡萝卜素含量相对较高,花色素苷和叶绿素所占比例位于绿色与红色系之间。该研究结果表明三叶海棠秋季叶色变化最直接的原因是色素含量与比例发生变化;叶片含有的原花青素B1、芦丁、绿原酸等单体酚作为辅色素对叶片成色起到辅助作用;三种色系叶片中的总黄酮含量由高到低依次为红色、黄色、绿色。     

一种半永久玻片标本的制备方法

这里介绍一种用蔗糖液制备半永久玻片标本的方法。用这种蔗糖液制备半永久玻片标本研究染色体是很方便的和有实际意义的。这种用蔗糖液制备的半永久玻片标本,可以保存较长时间(一年或更长)。蔗糖液的制备方法取40克蔗糖(化学纯)溶解在60毫升水中,并加热至沸,直至溶液总体积减少了1/4时为止。为避免蔗糖液冷却后出现结晶,要向蔗糖液滴入2—3滴香柏油,细心搅匀,然后再加0.2克苯酚结晶,该糖液可保存一个月以上。花药制片方法 1.从经卡诺固定剂(95％酒精:冰醋酸3:1)固定的保存在70％酒精中的花序上取出一些花药,用醋酸地衣红色液(醋酸洋红、醋酸间     

植物原色浸制标本的保存

不同植物、不同器官其颜色种类各有不同 ,制成标本如采用一般方法想长久保存原先颜色也很困难。笔者通过查资料 ,长期实践、摸索 ,终于找到较满意的制作方法。现介绍如下 :1　保存绿色　将标本浸入 30 % Cu SO4 溶液中 ,5～ 10天取出 ,用清水冲洗 ,再放入 0 .2 %～ 0 .3%的 H2 SO3溶液标本瓶中 ,密闭瓶盖。2　保存红色　用 2 2 0 g硼酸、150 ml福尔马林、10 0 ml75%～ 90 %酒精、2 0 0 ml蒸馏水制成保存溶液 ,将红色标本 ,如红枣、枸杞子或番茄等洗净浸入 ,然后密封容器口。3　保存紫色　将饱和精盐水 50 0 ml,福尔马林 2 50 ml、蒸馏水 …     

玫瑰切花保鲜剂配方研究

以蔗糖(S)、8-羟基喹啉(8-HQ)、柠檬酸(CA)为保鲜液的基本配方,分别加入CaCl2 、NaCl、Al2(SO4)3、CaCl2+KAl(SO4)2 组成四种保鲜液,进行玫瑰切花保鲜实验。对切花瓶插寿命、花径、水分平衡值、可溶性蛋白含量和还原糖含量进行分析。结果表明,各种配方保鲜液均能延长玫瑰切花的瓶插寿命、增大花径、改善切花水分代谢状况、降低切花蛋白质和还原糖的分解速度。其中,保鲜液2% S + 280 mg/L CA + 200 mg/L 8-HQ + 1% CaCl2的保鲜效果最好。     

柑桔类标本保色浸制法

柑桔类果实长期保持鲜艳颜色的浸制液配方:蒸馏水或凉开水93％,亚硫酸4％,甘油3％。使用时,可按上述比例根据需要量配制。     

峨眉山野生金蝉花孢梗束培养试验

为确定峨眉山金蝉花孢梗束培养的最佳工艺条件,对金蝉花孢梗束生长的常用培养基配方进行筛选试验,选用大米、小米、黄豆等原料进行配方试验,采用均匀设计试验法优化培养基配方。结果表明,金蝉花在以无机盐为主要营养成分的Richard琼脂培养基和Czapek琼脂培养基上均能产生孢梗束。在大米等的配方试验中,以大米为营养物质的金蝉花孢梗束生长最快,金蝉花氨基酸含量为23.4%,粗多糖含量为26.5%,蛋白质含量为29.3%,均高于野生金蝉花中该物质的含量。在均匀设计的配方试验中,10号培养基中的金蝉花孢梗束以珊瑚状为主,菌体形态最好,孢梗束产率可达57.4%。10号配方孢梗束中蛋白质的含量高达42.5%,氨基酸含量高达33.3%,均远高于野生金蝉花。     

Reward Tracking and Memory Decay in the Monarch Butterfly,Danaus plexippus L. (Lepidoptera: Nymphalidae)

Due to their long‐distance migration routes and high longevity, monarch butterflies (Danaus plexippus) are likely to benefit from learning how to discriminate and remember suitable feeding resources. In this study, we assessed monarchs’ abilities to track changing nectar sources over time and to retain learned information presented in two conditioning schedules. Non‐preferred (blue and red) and preferred (yellow) artificial flowers were concomitantly offered to monarchs in a three‐phase experiment. In each phase, flowers of only one color contained sucrose solution, while the others contained water. The rewarding color was changed in each phase. Instantaneous observations were made to assess butterfly visits to each color during each phase; continuous observations over the first 90 min of a new phase allowed us to look in more detail at the transition process. Overall, monarchs tracked sucrose availability, visiting the rewarding flowers more often than the unrewarding ones, regardless of innate preferences. However, butterflies reverted to innate color preferences when the newly rewarding color was different from the initial trained color. In a second experiment, memory decay was compared for butterflies trained according to two schedules: ‘single training’ (sucrose solution in red vs. water in blue artificial flowers in one 15‐min session per day) or ‘intermittent training’ (as above, but in two 7.5‐min sessions per day). Afterwards, butterflies were tested on alternate days for a week in arrays containing unrewarding models of both colors. Following either training schedule, memory persisted for at least 3 d after reinforcement ceased. Our findings reveal that monarchs are able to change their feeding responses according to the flowers’ reward status despite innate preferences, as well as to retain flower information for about half a week regardless of the conditioning dynamics.     

Collodion Fixation and Protection of Cytological Smears for Transportation and for Staining by Papanicolaou's Method

A 1% collodion solution in a 1:1 mixture of 95% alcohol and ether can be used to fix smears and to form a protective coating on them. Such coating permits transportation of dry slides over long distances to a laboratory for staining and diagnosis. The collodion solution can be used several times provided that it is filtered after each specimen is coated. With urine sediments, the application of the coating keeps a large number of cells on the slide, hence facilitates a thorough examination and more reliable diagnosis. Papanicolaou's method is recommended for staining the coated specimens, especially those for the diagnosis of cancer.     

Collodion Fixation and Protection of Cytological Smears for Transportation and for Staining by Papanicolaou's Method

A 1% collodion solution in a 1:1 mixture of 95% alcohol and ether can be used to fix smears and to form a protective coating on them. Such coating permits transportation of dry slides over long distances to a laboratory for staining and diagnosis. The collodion solution can be used several times provided that it is filtered after each specimen is coated. With urine sediments, the application of the coating keeps a large number of cells on the slide, hence facilitates a thorough examination and more reliable diagnosis. Papanicolaou's method is recommended for staining the coated specimens, especially those for the diagnosis of cancer.     

Simultaneous Differential Staining of Cartilage and Bone in Rodent Fetuses: an Alcian Blue and Alizarin Red S Procedure without Glacial Acetic Acid

Differential staining of cartilage and bone has several applications including developmental toxicology studies of new chemical candidates for pharmaceutical, industrial, and environmental use. It has been more common to stain fetal bone only using the dye alizarin red S: however, failure to evaluate the cartilaginous portion of the skeleton may result in the failure to identify toxicologically important alterations in skeletal morphology. Previously, differential staining of fetal cartilage and bone was best achieved by combining alizarin red S for staining bone with alcian blue to stain cartilage in glacial acetic acid solution: however, occupational hazards posed by the use of glacial acetic acid make these methods undesirable. Replacement of the glacial acetic acid with potassium hydrogen phthalate eliminates these hazards without compromising the quality of the stained specimen.     

A One-Solution Triacid General Stain Which Differentiates Oxygenated from Non-Oxygenated Red Blood Corpuscles

Tissues from representative mammals, amphibia and invertebrates were fixed for 5-24 hr in either an aqueous solution of 8% p-toluene sulfonic acid (PTSA) or in 10% formalin to which 5 gm PTSA/100 ml had been added, and processed through embedding in polyethylene glycol 400 distearate in the usual manner. Sections cut at 4-6 μ were floated on 0.2% gelatin containing 1.25% formalin, and spread and dried on slides at a temperature not exceeding 25 C. Wax was removed with xylene, and the sections brought to water through ethanol as usual. The working staining solution was made from three stock solutions: A. Chlorantine fast blue 2RLL, 0.5%; B. Cibacron turquoise blue G-E, 0.5%; C. Procion red M-P, 0.5%—each of which was dissolved in 98.5 ml of distilled water to which 0.5 ml of glacial acetic acid and 0.5 ml of propylene glycol monophenyl ether (a fungicide) had been added. For use, the three solutions were mixed in the proportions: A, 3; B, 4; and C, 3 volumes. Staining time was uncritical, 10-30 min usually sufficing for 6 μ, sections. The chief feature of the staining is the differentiation of oxygenated and nonoxygenated red blood corpuscles, in reds and blues respectively. Connective tissue stained blue or blue-green and mucin, green. Nuclei and cytoplasm stain according to their condition at the time of fixation. The mixed stain keeps well, remaining active after 2 yr of storage.     

Chemotaxonomic value of anthocyanins in Podalyria and Virgilia (tribe Podalyrieae: Fabaceae)

Anthocyanin pigments responsible for purple and pink flower colours in the tribe Podalyrieae have been identified. The considerable variation in flower colour is not reflected in the chemical variation and the flower pigments are surprisingly conservative. Virgilia flowers always have the acetic acid esters of cyanidin-3-glucoside and peonidin-3-glucoside as major compounds, together with trace amounts of the coumaroyl ester of cyanidin-3-glucoside. Podalyria flowers invariably have the rather more stable coumaroyl ester of cyanidin. The data support a close affinity between the two genera but also show that flower colour is only partially homologous.     

怒江石豆兰，中国兰科一新种

在野外和标本研究的基础上, 描述了中国兰科石豆兰属的一新种,怒江石豆兰, 并提供彩色图片和线条图。 怒江石豆兰与大苞石豆兰很近,但这两个种在花的颜色、侧萼片合生程度、花瓣形状等性状上区别明显。     

Differential Staining of Aborted and Nonaborted Pollen

A single staining solution was made by compounding it in the following order (dyes were from British Drug Houses): ethanol, 10 ml; 1% malachite green in 95% ethanol, 1 ml; distilled water, 50 ml; glycerol 25 ml; phenol, 5 gm; chloral hydrate, 5 gm; acid fuchsin 1% in water, 5 ml; orange G, 1% in water 0.5 ml; and glacial acetic acid, 1-4 ml. For best results in differentiation to give green pollen walls and red protoplasm, the staining solution should be acidified with glacial acetic acid. The amount of acid to be added depends upon thickness of the pollen walls: for very thin-walled pollen, 1 ml; for moderately thin walls, 2 ml; and for thick-walled or spiny-walled pollen, 3 ml of acid. For pollen inside non-dehiscent anthers, 4 ml of acid should be used. Staining is hastened by flaming the slide (for loose thin-walled pollen) or by immersing thick-walled pollen or anthers for 24-48 hr at 50 C. In the typical stain, aborted pollen grains are green; nonaborted, red. The method is useful for pollen inside nondehiscent anthers if these are small and not too deeply coloured naturally. The stain is very durable, especially if the coverslips are sealed with param wax. The staining solution will keep well for about a month. It is useful both for angiosperms and gymnosperm microgametes.     

Bulbophyllum nujiangense (Bulbophyllinae,Epidendroideae, Orchidaceae), a New Species from Yunnan,China

Based on field observation and specimen examination, a new species of Orchidaceae, Bulbophyllum nujiangense, is described and illustrated. Bulbophyllum nujiangense is closely related to B. cylindraceum in sect. Brachystachya in having tufted plants, large leaf, long inflorescence, small flowers in raceme, and fleshy lip, but can be easily distinguished from the latter in having flowers deep purplish red and whorl well spaced along the rachis, lateral sepals adhere to each other slightly at base, elliptic petals with obtuse and mucronate apex, lip deep purplish red.     

Control of Anthocyanin Synthesis in PETUNIA HYBRIDA by Multiple Allelic Series of the Genes An1 and An2

A mutable allele of the An1 locus in Petunia hybrida has given rise to a multiple series of stable derivative alleles. Anthocyanin concentration in mature flowers of these mutants (an1^{+/ p}/an1) decreases from the wild-type red to the recessive white in a continuous series. Anthocyanin composition changes regularly: the ratio of peonidin to cyanidin is 3.5 for an an1^+/+/ an1 and 1.2 for an an1^+/p5/an1 mutant. Analysis of anthocyanins during flower development indicates that these differences in composition are due to the specific state of the An1 locus and not to anthocyanin concentration. Anthocyanin concentration in flowers of the allelic series for An1 correlates with the activity of the enzymes UDP-glucose: flavonoid-3-O-glucosyltransferase and SAM: anthocyanin-3'- O-methyltransferase. The same correlations were found for members of a comparable allelic series at the An2 locus. The possibility that the correlation between the enzyme activities is due to the occurrence of a multienzyme complex is discussed.