沙门菌CWDMs苹果酸脱氢酶的检测

目的：了解沙门菌细菌壁缺陷突变株（CWDMs）的生物氧化及遗传特点和探讨细菌壁缺陷变异的性质与机制。方法：采用PAGE电泳法和分光光度法检测伤寒沙门菌和甲型副伤寒沙门菌及其CWDMs和伤寒沙门菌粗糙型和苹果酸脱氢酶（MDH）同工酶的活性与类型。结果：伤寒沙门菌和甲型副伤寒沙门菌的细菌型和伤寒沙门菌粗糙型经PAGE电泳可见一条MDH同工酶带,CWDMs电泳后可见两条MDH同Ⅰ酶带,在CWDMs的MDH中有一条泳动速率与细菌型及粗糙型的相同,另一条则较快。分光光度法检测证实。细菌型与粗糙型的MDH活性相似,CWDMs的MDH活性则明显较低。结论：CWDMs保留了与亲代细菌型一致的MDH和形成了一种新的MDH,并且其MDH的活性已显著降低,此特性可能与CWDMs生物氧化特性的改变有关。     

马占相思林冠蜘蛛群落的结构分析

用杀灭菊酯喷洒林冠,收集得蜘蛛２６种,１９９只。群落组成以不结网为为主,全年均保持较高数量水平。结网类从４月至１０月成指数曲数下降。４个相似样地上的群落结构显著差异。以ＭａｃＡｒｔｈａｒ分布模型为基础,求出每个种在群落中的数量－时间－空间的重要值。结果以斜蛛的ＮＴＤ为最,斑络新妇幼体为次。蜘蛛－昆虫群落的营养结构在各样地上是一致的。蜘蛛作为捕食者,占总数１２－１５％。     

INVESTIGATION OF THE STRUCTURE OF THE CORNIFIED EPITHELIUM OF THE HUMAN SKIN

To explore the submicroscopic structure of the human callus by the polarization optical method, serial sections were prepared in three principal planes and the sign of double refraction as well as optic axes of various regions of the sections was determined. It was concluded that in areas under the grooves keratin is oriented parallel to the surface plane of the callus and to the direction of the grooves. In component structures of ridge areas such as in sweat duct areas a circumferential, in cross-band areas a linear, and in other parts a random structure was seen. The cross-bands of ridge areas in association with groove areas revealed a regular lattice-like submicroscopic pattern which was considered as an important mechanical system of the cornified epithelium.     

A SURVEY OF THE RESULTS OF TREATMENT OF GASTRIC CANCER IN SAN FRANCISCO

A survey was made of all patients treated for gastric cancer on the clinic services of the Stanford University Hospital during the 30-year period 1919 to 1948. During the last decade of the survey there were impressive gains in the surgical treatment of this disease. It was possible from 1944 to 1948 to do a gastric resection on half the patients seen with cancer of the stomach. Also, there was a pronounced decrease in resection mortality so that from 1939 to 1948 the mortality rate for subtotal gastrectomy for cancer was 3 per cent.The over-all five-year survival rate was discouragingly low—4.6 per cent. On the other hand, 23 per cent of those surviving gastric resection lived for five years.A survey of the management of carcinoma of the stomach from 1939 to 1948 was made in 11 general hospitals in San Francisco. A wide range of resectability and resection mortality rates was observed. The cases from these hospitals were combined with those from Stanford for the same period to form a composite group of 1,128 patients. Analysis of this group of cases from 12 representative hospitals in San Francisco showed encouraging trends toward higher resectability rates with a lower resection mortality.     

蛋白质表面疏水性的研究

用Ｐｈｅｎｙｌ－ＳｕｐｅｒｏｓｅＨＲ５／５疏水柱在ＦＰＬＣ仪上测定了一些蛋白的表面疏水性。在被测量的蛋白样品中,细胞色素Ｃ的亲水性最强,胰凝乳蛋白酶的疏水性最强。说明蛋白质的疏水性与其表面性质密切相关,而与蛋白质的分子量、疏水残基总数并不直接相关;去辅基细胞色素Ｃ和Ｃ端缩短的金黄色葡萄球菌核酸酶与天然态比较疏水性变化很大。疏水柱层析还用于监测在低浓度胍的作用下蛋白质的构象变化。以Ｎ－乙酰酪氨酸为模型化合物探测盐酸胍对疏水柱结合能力的影响,在０４Ｍ胍存在时,Ｎ－乙酰酪氨酸在疏水柱上的结合能力略有减弱,但核糖核酸酶Ａ的变化较大,表明胍引起的蛋白质的微小构象变化有效地引起其表面性质的变化;在０．１—０．３Ｍ盐酸胍存在时,甘油醛－３－磷酸脱氢酶表面疏水性明显增大,并伴随聚合态的出现。说明在低胍作用下,酶分子发生的构象变化,导致天然态内埋疏水面的暴露,暴露的疏水面间的相互作用是形成聚合的主要原因。     

三叉神经中脑核神经元膜的电学特性

用大鼠脑干脑片,给三叉神经中脑核79个神经元作了细胞内记录,测算了20个神经元膜的电学特性:静息电位-60.3±5.6mV;输入阻抗为10.5±5.4MΩ;时间常数1.3±0.5ms。电刺激可诱发动作电位,测算32个神经元的有关参数:阈电位-50—-55mV;波幅69.5±6.1mV;超射11.9±3.6mV;波宽0.8±0.2ms。TTX(0.3μmol/L)或无钠使之消失。通以长时程矩形波电流可引起200—250Hz的2—15个重复放电,但在通电停止前终止,TEA或4-AP可延长放电。膜电位-60—-55mV时在动作电位之后可看到阈下电位波动,它不受TTX的影响,无钙时消失,TEA或4-AP使波幅增大。静息电位去极化可使45个神经元中的40个发生外向整流作用,并被TEA,4-AP或无钙抑制,超极化则发生内向整流作用,Cs或无钠抑制之。灌流液中加入各种钾通道阻断药时神经元的稳态I-V曲线发生相应变化,提示I_(DR),l_A,I_(K(Ca))及I_Q可能都与静息时的膜电导有关。     

EFFECT OF CHOLINE ON THE RATES OF SYNTHESIS and OF RELEASE OF ACETYLCHOLINE IN THE ELECTRIC ORGAN OF TORPEDO

Abstract— Slices of electric organ of Torpedo marmorata were chopped and incubated in a saline-urea-sucrose medium. This preparation of minced tissue exhibited a relative enrichment in ACh and nerve endings, which was attributed to a loss of electroplaque cytoplasm. Electron microscopic controls showed nerve endings of normal morphology, some of them forming 'chaplets' separated from electro-plaques. Miniature endplate potentials were recorded on sealed fragments also present in this preparation. ACh levels remained unchanged during incubation periods as long as 19 h. The time course of the incorporation of [1-¹⁴C]acetate of [2-¹⁴C]pyruvate into ACh pools was studied. These incorporations were similarly affected by the choline added to the medium. In the presence of increasing choline concentrations (up to 10^-4 m ), the incorporation of [¹⁴C]acetate or [¹⁴C]pyruvate into ACh increased. They both diminished when choline was added above 10^-4M. The ACh content of the tissue was not affected by added choline. From the constancy of ACh levels in the presence of various choline concentrations and from the steady state of our preparation, we can conclude that the release of transmitter varied in parallel to the incorporation rate of the precursor of the acetyl moiety of ACh. This fact was also found using the efflux of [¹⁴C]acetate as an evaluation of ACh release. The values of release calculated by this method were in good agreement with those determined from the incorporations of acetate and pyruvate into ACh. It is suggested that the primary action of choline is on its high affinity carrier system. This triggers a secondary action on the ACh release mechanisms.     

THE EFFECT OF TIME OF APPLICATION OF NITROGENOUS FERTILIZER ON POWDERY MILDEW OF WINTER WHEAT

Applying nitrogenous fertilizer (N) to wheat plants of different ages affected the incidence of powdery mildew, Erysiphe graminis DC, differently. When N was applied before the flag leaf had emerged, the infection-index (number of pustules per 100 sq.cm. of leaf blade) increased to a maximum and then declined. If N was applied after the flag leaf had emerged, the infection-index increased steadily without reaching a peak, and the increased susceptibility was not associated with an increased relative leaf growth rate as when N was applied earlier.
The integral of the number of pustules per unit area with time, and the number of perithecia on the leaves of the main stem, both increased with increasing delay in the application of N. Plants given N in either April or May had at least three times as many pustules as those given N in January. The time when N was applied did not affect the date when perithecia appeared.
After adding N to nitrogen-deficient plants, the already mature leaves which had resisted mildew infection, became susceptible. This change is not associated with changes in the epidermal wall.     

EFFECT OF HYPERPHENYLALANINEMIA ON FATTY ACID COMPOSITION OF LIPIDS OF RAT BRAIN MYELIN

Abstract— We have studied the fatty acid compositions of cerebral myelin lipids in phenyl-alanine-treated and control rats. The proportion of long chain fatty acids and the ratio of unsaturated to saturated fatty acids of whole brain lipids was low in the penylalanine-treated animals. Both of these reductions were more pronounced in the myelin from phenylalanine-treated rats. The ratio of unsaturated to saturated fatty acids in ethanolamine phosphatides was markedly decreased in the hyperphenylalaninemic condition. The reduction in the proportion of long chain fatty acids was predominant in non-hydroxy fatty acids in cerebrosides and ethanolamine phosphatides. The lipid composition of the myelin expressed as mole percentages of individual phospholipid and sphingolipid components was not significantly different in the two groups of rats, nor did it change with age. Our results indicate a deficiency in the fatty acid elongation and desaturation system in the brains of phenylalanine-treated rats. We suggest that in hyperphenylalaninemic rats, a reduction in the amounts of unsaturated fatty acid and long chain fatty acid alters, respectively, the biochemical reactivity and the stability of the myelin.     

不同食物饲养幼鼠对肝组织化学影响的观察

实验采用刚断乳的幼鼠２０ 只, 分为两组喂养, 每组１０ 只, 对照组和普通饲料喂养（简称Ａ 组）,另一组用奶粉喂养（简称Ｂ组）。分别喂养２０天后, 对其肝组织化学进行了分组定性对比观察。结果显示：Ａ 组肝细胞糖原ＰＡＳ反应, ＳＤＨ、ＣｈＥ活性高于Ｂ组, 分别为强阳性（）, 而Ｂ组ＬＤＨ, ＡＫＰ活性比Ａ组强, 分别为强阳性及最强阳性 （, ）。     

THE USE OF SOLUBILITY AS A CRITERION OF PURITY OF PROTEINS : I. APPLICATION OF THE PHASE RULE TO THE SOLUBILITY OF PROTEINS. II. THE SOLUBILITY CURVES AND PURITY OF CHYMOTRYPSINOGEN

1. The conditions under which the phase rule may be applied to systems containing proteins are formulated. 2. An attempt was made to fractionate chymotrypsinogen, by crystallization in stages with increasing concentration of magnesium sulfate. No significant fractionation of the protein was achieved, but a small amount of impurity which affects the solubility, while having little influence on other properties of the material, was concentrated in the fractions first precipitated. 3. The solubility of the final fraction was independent of the amount of the saturating solid, from the first appearance of a solid phase, in solvents of three different pH''s. The solubility was independent of the environment in which the crystals were formed (within the limits in which crystallization can be carried out) and the same value was reached from the supersaturated as from the undersaturated side. This material, therefore, conforms closely with the phase rule criteria of a pure protein.     

ULTRASTRUCTURE OF THE METABASIDIUM OF AURICULARIA FUSCOSUCCINEA

Maturation of the metabasidium of Auricularia fuscosuccinea was followed with light microscopy and transmission electron microscopy. The basidium was divided into four compartments by septa which developed centripetally as in hyphae. Each septum formed a septal pore apparatus with imperforate pore caps. A band of electron-dense material was situated in the middle of the septal pore. There was a large increase in the volume of cytoplasm, excluding vacuoles, in each compartment during sterigmal outgrowth. Compartments were evacuated in basipetal sequence and vacuole enlargement began at the base of a compartment only when sterigmal formation was well advanced. The septal pore apparatus was intact until late in maturation of a compartment when septal swellings occluded the pore. The metabasidial wall was differentiated from those of other hymenial and subhymenial cells. The pattern of basidial maturation is compared with that in other phragmobasidiate and holobasidiate fungi. Use of the septal pore apparatus for phylogenetic and taxonomic purposes is discussed, as is the concept of primary and adventitious septa.     

IMPROVEMENT OF TRIANGLE TEST DATA BY USE OF INCENTIVES

The objectives of this study were to determine the distribution of the sensory panelists' ability to detect differences and to improve the triangle test by minimizing unnecessary guessing. The triangle test was modified to include the use of economic incentives through which panelists voluntarily revealed their ability to detect differences. Panelists were asked to estimate their ability to detect differences and the probability of identifying the odd sample in a triangle test. They were then organized into three ability groups according to their responses. Double triangle tests, followed by triangle tests with economic incentives, were used to evaluate a cereal product and a beverage. The ability to detect differences was modeled as a probability, and the distribution of panelists was estimated. The economic incentives test was more effective when used with the beverage in which differences were less difficult to detect. We found that the economic incentive test discouraged the panelists from guessing unnecessarily, thus increasing the motivation of the panelists to detect differences, and allowing researchers to determine the distribution of discrimination ability.     

COMPARISON OF THE FATTY ACIDS OF LIPIDS OF SUBCELLULAR BRAIN FRACTIONS

Abstract— Rat brain grey and white matter were fractionated to yield myelin, nerve terminal, synaptic vesicle, nerve terminal 'ghost', and microsomal fractions of white and grey matter. Ester-type glycolipids were found in all fractions except myelin, while cerebrosides occurred in significant concentrations only in myelin and white microsomes. Comparison of the fatty acid profile of the ethanolamine- and serine-containing phospholipids showed marked differences between myelin and the particles from grey matter, while the microsomes of white matter were of intermediate composition. Docosahexaenoic acid, a minor acid in myelin, was a major fatty acid in microsomes of grey and white matter. The fatty acid composition of sphingomyelin was distinctly different in the fractions derived from grey and white matter, clustering about stearate and nervonate in the latter, but only about stearate in the grey. Marked differences in the positional distribution of fatty acids were seen within phosphatidyl choline from myelin and nerve terminals. Ribonucleic acid was found in nerve terminal and synaptic vesicle fractions. The sphingosine found in the ganglioside from microsomes of both grey and white matter was similar with respect to distribution of the C₁₈ and C₂₀ homologues.
The possibility is discussed that microsomes furnish characteristic lipids for the synthesis or renewal of specific membranes, and that these lipids are accumulated somewhat before being released.     

自然三倍体韭的发现

韭(Allium tuberosum Rottl. ex Spreng.) 原产我国,由于抗逆性强,栽培容易,又具有特异的辛香气味,自古以来就是群众喜爱的蔬菜品种之一。据文献记载,栽培的韭有二倍体和四倍体两类,分别由野生的二倍体韭和四倍体韭经长期驯化而来。栽培的四倍体韭产量比二倍体高。目前各地的商品韭多为四倍体,二倍体已不多见,而     

EFFECT OF INSULIN ON LEVELS AND TURNOVER OF INTERMEDIATES OF BRAIN CARBOHYDRATE METABOLISM IN VIVO

Abstract— –The rates of incorporation of ¹⁴C from [U-^l4C]glucose into intermediary metabolites have been measured in rat brain in vivo. The time course of labelling of glycogen was similar to that of glutamate and of glucose, which were all maximally labelled between 20 and 40min, but different from lactate, which lost radioactivity rapidly after 20min. The extent of labelling of glycogen (d.p.m./ μ mol of glucose) was of the same order as that of glutamate at 20 and 40 min after injection of [¹⁴C]glucose. However, calculations of turnover rates showed that glutamate turns over some 8-10 times faster than glycogen. Insulin, intracisternally applied, produced after 4-5 h a 60 per cent increase in glucose-6-P and a 50 per cent increase in glycogen. There was no change in the levels of glucose, glutamate or lactate, nor in the activity or properties of the particulate and soluble hexokinase of the brain. The injection of insulin affected neither the glycogen nor glucose contents of skeletal muscle from the same animals. The effects of insulin on the incorporation of ^l4C into the metabolites contrasted with its effects on their levels. The specific activities of glycogen and glucose were unchanged and there was a slight but non-significant increase in the specific activity of glutamate. The time course of incorporation into lactate was unaffected up to 20 min, but a significant delay in the loss of ¹⁴C after 20 min occurred as a result of the insulin injection. At 40 min, the specific activity of cerebral lactate was 60 per cent higher in insulin-treated animals than in control animals. The results are interpreted in terms of an effect of insulin on glucose uptake to the brain, with possibly an additional effect on a subsequent stage in metabolism, which involves lactate.     

THE EFFECT OF TENSION OF DISSOLVED OXYGEN ON THE TOXICITY OF UN-IONIZED AMMONIA TO SEVERAL SPECIES OF FISH

The resistance to rapidly lethal concentrations of un-ionized ammonia ranging from about 2.0 to 8.8 p. p. m. N was determined for rainbow trout ( Salmo gairdnerii Richardson), perch ( Perca fluviatilis L.), roach ( Rutilus rutilus (L.)), and gudgeon ( Gobio gobio (L.)) in tensions of dissolved oxygen 53.4 and 96.7% of air-saturation value at 15.2°C.
The relation between concentration of un-ionized ammonia and period of survival from a few hours to 13 days was investigated for rainbow trout in two tensions of dissolved oxygen, 45.7 and 100.3% of air-saturation value, at 20.1°C.
Period of survival of all the species tested decreased with rise in concentration of un-ionized ammonia.
Decrease in tension of dissolved oxygen increased the toxicity of un-ionized ammonia to all species except gudgeon, for which there was no significant difference in period of survival at the two levels of oxygen.
The effect of oxygen tension on period of survival was greatest in the lowest concentrations of un-ionized ammonia.
Resistance of perch and roach to lack of oxygen was not significantly affected, but that of rainbow trout was reduced significantly, by the presence of a small concentration of ammonia (not toxic to trout within at least 13 days).     

柳江化石智人的身高

作者将柳江人的右侧股骨残段作了复原。根据华南人由肢骨测量身高的公式,如果柳江人股骨属男性,其身高为156.69±3.74厘米,比现代当地居民的平均身高偏矮。     

亚热带地区部队皮肤真菌病及其病原菌的调查研究

亚热带地区是皮肤真菌病的高发地区,据报道,云南边防某部皮肤真菌病发病率为57.8％,占皮肤病发病率的第一位,美军在越南战争期间,发生的所有皮肤病中,最常见的是皮肤真菌感染,而且造成了非战斗减员。战争后期,美军把皮肤病的防治作为其疾病防治的重点。因此,我们于1992年10月底对海南地区部队皮肤真菌病的发病情况进行了流行病学凋查,并对皮肤真菌病的病原菌进行了分离鉴定,现报告如下。     

MODE OF NUCLEAR DIVISION IN SYNCHRONOUS CULTURES OF CHLORELLA: COMPARISON OF VARIOUS METHODS OF SYNCHRONIZATION

1. Chlorella ellipsoidea was grown synchronously using variouspossible techniques and the mode of nuclear division in eachcase was followed by staining the nuclei according to FEULGEN.
2. A satisfactory synchrony in respect to nuclear and cellulardivision was obtained by starting the culture from a homogeneouspopulation of young and small cells and by discontinuing theillumination at the stage which was called the L₃-stage. Thestarting young cells were invariably mononuclear and the L₃-cellswere either dinuclear or tetranuclear. When the L₃ were incubatedin the dark, they ripened further, and after passing througha tetranuclear stage (referred to as the L₄) divided into fourmononuclear daughter cells which have been called the D_n-cells.The most clear-cut and repetitive synchronous culture was obtainedwhen the culture (in the light) was started from the D_n-cellsand the illumination was discontinued at the L₃-stage untilthe fully ripened cells divided into four each of D_n-cells.
3. An apparently "synchronous" culture was also obtained by themethod of programmed light-and-dark regimen, in which a randomculture is subjected to a regular alternation of light and darkperiods of adequate durations. In this case, however, the cellsat different stages of culture showed irregular nuclear patterns,and the average "division number" of mother cells was not constant,being subject to change between 4.0 and 4.9.

(Received May 25, 1961; )