Shear dependence of effective cell volume as a determinant of blood viscosity

The viscosity of suspensions of human erythrocytes (normal cells in plasma, normal cells in Ringer's solution containing albumin, and hardened cells in Ringer's solution containing albumin) was measured over a wide range of shear rates, and the macrorheological data were correlated with the microrheological behavior of erythrocytes and rigid particles. The formation of rouleaux increases the effective volume of erythrocytes as a result of (i) the increase in axial ratio and (ii) the limitation of deformation of individual erythrocytes. The effective cell volume is the fundamental determinant of blood viscosity.     

Synthesis of the pyrrole porphobilinogen by sepharose-linked -aminolevulinic acid dehydratase

delta-Aminolevulinic acid dehydratase from Rhodopseudomonas spheroides was covalently linked to Sepharose 4B, which had been activated with cyanogen bromide. A column containing this enzyme gel readily catalyzed the synthesis of the pyrrole porphobilinogen on continuous passage of a solution of delta-aminolevulinic acid. Under the conditions of the procedures, product inhibition was minimized and a 50 to 94 percent yield was attained. A column containing about 1 milligram of enzyme was continuously operated for 27 days. Although its total activity appeared to be reduced about 30 percent at the end of this time, the bound enzyme produced approximately 200 milligrams of porphobilinogen each day, and about 5 grams of the pyrrole were isolated.     

金菇露的营养价值与保健作用初报

用金针菇固体培养物经生化水解加工的金菇露营养液,含有18种游离氨基酸,氨基酸总量比栽培的及野生的子实体高1.2-1.85倍,8种人体必需的氨基酸含量也比鲜菇高,但在氨基酸总量中所占的比例较低,它与鲜菇类似含有多种维生素如 VA 原、VB、VB_2、VC 等,还含有维生素 E,对小白鼠肉瘤 S_(180)、S_(37)及宫颈癌 U_(14)有明显的抑制作用,抑瘤率都在40%左右,最高达48.2%。还观察了一些疾病患者服用金菇露后的初步疗效.     

Synthesis of reverse osmosis membranes by plasma polymerization of allylamine

The polymerization of allylamine in a radio-frequency electrodeless plasma to form thin polymer films on microporous filter media provides very effective dry composite membranes for reverse osmosis. Salt and urea rejections as high as 98 percent and 46 percent, respectively, have been achieved from a solution containing 10 grams of sodium chloride per liter and 10 grams of urea per liter. The plasma conditions and polymerization technique are discussed.     

Cohenite in meteorites: a proposed origin

Cohenite [(Fe, Ni)(3)C] is found almost exclusively in meteorites containing from 6 to 8 percent nickel (by weight). On the basis of iron-nickel-carbon phase diagrams at 1 atmosphere and of kinetic data, the occurrence of cohenite within this narrow composition range as a low-pressure metastable phase and the nonoccurrence of cohenite in meteorites outside the range 6 to 8 percent nickel can be explained. Cohenite formed in meteorites containing less than 6 to 8 percent nickel decomposed to metal and graphite during cooling; it cannot form in meteorites containing more than about 8 percent. The presence of cohenite in meteorites cannot be used as an indicator of pressure of formation. However, the absence of cohenite in meteorites containing the assemblage, metal plus graphite, requires low pressures during cooling.     

Germination and appressorium formation of Pyricularia oryzae Cavara can be inhibited by reduced concentration of Blasin®Flowable with carbon dioxide microbubbles

We investigated the possibility to reduce the usage of Blasin^®Flowable (BF), a disinfectant inhibiting the germination and appressorium formation of Pyricularia oryzae Cavara conidia, by using carbon dioxide microbubbles (CO₂MB). Germination was significantly inhibited by 10 000-fold diluted BF solution containing CO₂MB generated by the decompression-type generator compared to CO₂ millibubbles (CO₂MMB) and CO₂MB generated by the gas-water circulating-type generator. Appressorium formation in the 10 000-fold diluted BF solution containing both CO₂MBs was less than that in CO₂MMB. Scanning electron microscopy showed wrinkles and dents on the surface of conidia treated with 5 000-fold diluted BF solution containing both CO₂MBs. Via transmission electron microscopy, we observed the expansion of the vacuole and the intracellular space and bloated or absent lipid granules in the conidia treated with BF solution containing both CO₂MBs. Our results show that inhibition of the conidium germination and appressorium formation of P. oryzae Cavara by 10 000-fold diluted BF solution could be achieved by using the decompression-type CO₂MB.     

Fatty Acids: In vivo Synthesis by the Green Peach Aphid, Myzus persicae (Sulzer)

After feeding through an artificial membrane on an 18 percent sucrose solution containing either acetate-1-C(14) or uniformly-labeled glucose-C(14), Myzus persicae incorporated 75 percent of the carbon-14 into palmitoleic, stearic, and oleic acids. Small amounts were incorporated into myristic, linoleic, and linolenic acids; no significant amounts were incorporated into the short-chain fatty acids.     

Brush border particulates of renal tissue

Particulates containing a large part of the alkaline phosphatase activity of renal tissue were separated from homogenates and from ribosomal preparations by zonal centrifugation. The particles had a high content of phospholipid and cholesterol that was not removed by treatment with I percent deoxycholate. Enzymatic activities concentrated with the particles were the alkaline phosphatase, a peptidase resistant to proteolysis, glucose-6-phosphatase, inorganic pyrophos-phatase, and adenosine triphosphatase. The particles accumulated leucine with no stimulation from soluble factors and with inhibition by other amino acids; the accumulation was stimulated by adenosine triphosphate and was not inhibited by puromycin. The particles appear to be derived from the membranes of the brush borders of tubular cells.     

烤烟专业分级散叶收购烟叶等级质量评价

为探讨烤烟专业分级散叶收购的等级质量,提高分级合格率,对2009~2012年毕节市烤烟专业分级散叶收购、把烟收购的烟叶等级质量进行分类、对比分析,结果表明:烤烟专业分级散叶收购等级纯度高,混有非原等级1~3个,原级比例≥60%、原级与邻级之和比例≥90%,比把烟收购解把后片烟混有非原级平均减少2.7个;烤烟专业分级散叶收购较把烟收购,含邻级比例、原级与邻级比例平均高9.61、18.82百分点;在工商交接中,经过专业分级散叶原级比例≥65%、原级与邻级之和比例≥95%,达到了烟草工业企业要求。     

不同清洗方法对果蔬表面敌敌畏的去除效果分析

为研究不同清洗方法对果蔬表面敌敌畏的去除效果,将黄瓜、娃娃菜、桃子、苹果4种果蔬分别用清水冲洗、清水浸泡、碱水浸泡、淘米水浸泡、盐水浸泡、果蔬清洁剂浸泡,温度40℃处理10min后,利用酶抑制剂法快速检测敌敌畏的去除效果。结果表明:各清洗方式均对果蔬表面敌敌畏有一定去除效果,但去除效果存在差异,其中果蔬清洁剂效果最好,对高残留的桃子也具有较好的去除效果,从而使其对乙酰胆碱脂酶的抑制率从79.6%降至24.5%,采用清水冲洗效果则有限,对于低残留的苹果,残留敌敌畏对乙酰胆碱酯酶的抑制率从46.5%降至25.2%,而高残留的桃子从79.6%降至56.8%,未达到食用标准。     

Contributions of two types of calcium channels to synaptic transmission and plasticity

In Aplysia sensory and motor neurons in culture, the contributions of the major classes of calcium current can be selectively examined while transmitter release and its modulation are examined. A slowly inactivating, dihydropyridine-sensitive calcium current does not contribute either to normal synaptic transmission or to any of three different forms of plasticity: presynaptic inhibition, homosynaptic depression, and presynaptic facilitation. This current does contribute, however, to a fourth form of plasticity--modulation of transmitter release by tonic depolarization of the sensory neuron. By contrast, a second calcium current, which is rapidly inactivating and dihydropyridine-insensitive, contributes to release elicited by the transient depolarization of an action potential and to the other three forms of plasticity.     

Flow Characteristics of Human Erythrocytes through Polycarbonate Sieves

We used polycarbonate sieves with uniform cylindrical pores (2.4 to 6.8 microns in diameter) to filter suspensions of human erythrocytes (mean major diameter is 7.2 microns) in Eagle-albumin solution. With 6.8-micron sieves the pressure-flow curves are convexed to the pressure-axis at low pressures and become linear with high pressures. With 4.5-micron sieves, however, the pressure-flow relationship is linear throughout the range of study. In both types of sieves, flow rate is reduced progressively with increasing concentration of red blood cells (RBC) over a range of 0.5 to 95 percent. The resistance to flow of RBC suspensions is higher in 4.5-micron than in 6.8-micron pores. With filter pore diameters of 3.0 microns or more, the RBC concentration in the filtrate was 100 percent of that in the solution being filtered, but only 70 percent with 2.4-micron pores. The observed critical pore diameter for 100 percent cell transmission agrees with theoretical calculation based on the assumption that the RBC membrane is deformable but nonextensible. The importance of cell deformation in the passage of RBC's through small pores is shown by the inability of RBC hardened in acetaldehyde to pass pores with 6.8-micron diameter.     

Antagonism of veratrine by calcium ion in monolayers of stearic acid

Force-area diagrams for monolayers of stearic acid on Ringer's solution demonstrate a competition between veratrine and calcium for carboxyl groups of the films. The competition occurs at customary concentrations. Local anesthetics act quite differently. The interactions suggest those observed less directly in living cells and therefore indicate that such surface films may serve as models for the study of drug and ion effects.     

Respiration of heart muscle as affected by oxygen tension

Isolated cat papillary muscles were exposed to gas mixtures containing carbon dioxide and oxygen. In muscles exposed during the second of three periods to 25 percent oxygen, the volume of oxygen consumed (Q(o2)) was depressed by 50 percent, but returned to the control level during a third period at 98 percent oxygen. The work capacity was not significantly altered if the partial pressure of oxygen was low.     

Corchorus pascuorum: transmission of chemically induced fruit formation with environmental change

When Corchorus pascuorum (Tiliaceae), native to Australia, was grown in the arid region of West Pakistan, it flowered abundantly but produced no fruit. It was induced to form fruit by treatment with 25 percent sucrose solution containing indolebutyric acid (300 parts per million). When plants were raised from the induced fruits, they fruited without any further treatment and retained the ability to produce fruits in two subsequent generations, whereas those raised from the original seeds produced no fruit.     

Calcium current and activation of contraction in ventricular myocardial fibers

In thin bundles of dog ventricular myocardium, a slow inward current (distinct from the sodium inward current) could be recorded under voltageclamp conditions. This inward current was influenced by changes in external calcium concentration, but it was not dependent on external sodium concentration. Therefore, this current which contributes an appreciable amount of charge transfer during the plateau of the action potential, is carried by calcium ions. In sodium-free solution, the flow of calcium ions into the fiber is directly related to activation of contraction. In sodium-containing solution, however, calcium inward current serves primarily to fill up some intracellular stores from which calcium can be released by moderate depolarization.     

Venting of carbon dioxide-rich fluid and hydrate formation in mid-okinawa trough backarc basin

Carbon dioxide-rich fluid bubbles, containing approximately 86 percent CO(2), 3 percent H(2)S, and 11 percent residual gas (CH(4) + H(2)), were observed to emerge from the sea floor at 1335- to 1550-m depth in the JADE hydrothermal field, mid-Okinawa Trough. Upon contact with seawater at 3.8 degrees C, gas hydrate immediately formed on the surface of the bubbles and these hydrates coalesced to form pipes standing on the sediments. Chemical composition and carbon, sulfur, and helium isotopic ratios indicate that the CO(2)-rich fluid was derived from the same magmatic source as dissolved gases in 320 degrees C hydrothermal solution emitted from a nearby black smoker chimney. The CO(2)-rich fluid phase may be separated by subsurface boiling of hydrothermal solutions or by leaching of CO(2)-rich fluid inclusion during posteruption interaction between pore water and volcanogenic sediments.     

Phytotoxic Substance from a Species of Penicillium

A Penicillium urticae Bainer, isolated from subsurface-tilled plots showing reduced wheat growth, produced a phytotoxic substance. The melting point and infrared and ultraviolet spectra of the crystalline material showed this substance to be patulin. Wheat shoot growth inhibition of 50 percent required 20, 20, and 75 parts per million of patulin in solution, sand, and soil culture, respectively.     

新疆乳菀属时表皮特征及其分类学意义

本研究在扫描电镜（ＳＥＭ）和光镜（ＬＭ）水平上对产于新疆的轧菀属（ＧａｌａｔｅｌｌａＣａｓｓ．）１１种植物叶表皮进行了比较观察，表明该属植物叶表皮细胞和气孔也均为不规则型。文章认为，乳菀属叶表皮特征较稳定，且具有类群特异性，在确定亲缘关面具有重要意义。     

Inhibition of human acute lymphoblastic leukemia cells by immunotoxins: potentiation by chloroquine

Immunotoxins containing pokeweed antiviral protein and monoclonal antibodies against human T cells or human transferrin receptor efficiently killed acute lymphoblastic leukemia cells. Chloroquine specifically enhanced the rate of protein synthesis inhibition by immunotoxin. Depending on its concentration, chloroquine (10 to 100 micromolar) reduced by up to 65-fold the amount of immunotoxin required to inhibit protein synthesis in the target cells 50 percent.