Failure to Maintain Glycolysis in Anoxic Nerve Terminals

Synaptosomal glycolysis is stimulated eight- to 10-fold when the respiratory chain is inhibited by cyanide or by anoxia. However, the stimulation is transient and after 15 min declines toward the preanoxic rate. The decline is not seen when Ca2+ is absent or when the respiratory chain is inhibited by rotenone. The decline in glycolysis is reversible, is not due to substrate exhaustion, and is the cause, rather than the effect, of lowered synaptosomal ATP/ADP ratios. The failure to maintain glycolysis when the terminal oxidase of the respiratory chain is inhibited may have relevance to the sensitivity of the brain to anoxic damage.     

沙冬青淀粉粒及其与叶绿体发育的关系

沙冬青叶绿体中的淀粉粒一般为１－３个,主要有４种类型。第１种外周部分电子密度较高,中央部分较低,但每个部分的电子密度十分均匀。它们近似椭圆形,附近的类囊体形态正常,结构清晰。第２种电子密度由外向内逐渐变低,多为椭圆形,附近的类囊体较清晰。第３种外周部分的电子密度很高,中央部分不均匀,形状多种多样,附近的类囊体有的不清晰。第４种电子密度很低,十分均匀,形状不规则,附近的类囊体已经解体或正在解体。分析表明,淀粉的形态变化明显与叶绿体发育有关。     

糖、糖、“糖”——什么是糖?

糖类是自然界中最常见的一类生物分子,但是糖类因不同的人群可以有三种不同的理解.一是科学上的糖类,二是生活中的糖类,三是作为甜味剂的"糖"类.因为甜味是一个生理上的感觉,凡能与甜味受体相互作用的均是甜味剂,其中有些是糖的"糖",也有不是糖的"糖".     

杉木人工林水量平衡和蒸散的研究

 本文根据我们严密设计的小集水区径流场连续6年的水文测定数据,进行了杉木人工林水量平衡和蒸散的研究。结果表明：集水区年平均降雨量1065.5mm, 在林冠作用面降雨量的分配中,林冠截留雨量264.6mm,截留率24.8%;穿透过林冠层的雨量799.82mm,树干径流量1.08mm,分别占降雨量的75.1%和0.1%。林内降水到达林地时,在枯枝落叶层这个作用面上净降水进行再分配,其中,地表径流量9.27mm,地下径流量203.00mm,总径流系数0.199。土壤蓄水量月变化较大,但年变化很小,占降雨量的1.2%。系统水量最大的输出是蒸散,每年以气态形式返回大气的水量866.03mm,占降雨量81.3%。在蒸散的水量中,林冠截留雨量的直接物理蒸发量为264.6mm,占总蒸散量的31.6%。     

药敏药片对临床235株细菌实验观察报告

药敏药片经临床对金黄色葡萄球菌、大肠埃希氏菌、铜绿假单胞菌等２３５株考核．表明药片工艺研究先进,药片与培养基结合牢固,无断裂、崩解,不渗出颗粒,抑菌圈呈同心园扩散．边缘清楚。药物含量均匀,释放度好。药片抑菌差仅１～３ｍｍ;而纸片抑菌差为２～１２ｍｍ。药片变黑系数ＣＶ为２．７１～４．２１;而纸片ＣＶ为３．８２～１４．３６。表明纸片片间差大,药片精密度明显好于纸片。     

矮沙冬青雌配子体及胚胎发育研究

矮沙冬青子房单心皮1室,边缘胎座,弯生胚珠,胚珠具双珠被、厚珠心。大孢子孢原细胞发生于珠心表皮下,大孢子母细胞减数分裂形成直线排列的四分体,合点端大孢子具功能,并按蓼型胚囊发育,雌配子体成熟于4月中旬。双受精后,胚乳发育为核型。在矮沙冬青大孢子发生、雌配子体和胚胎发育过程中未发现异常现象,因此认为矮沙冬青濒危不存在雌性生殖结构与发育过程异常的内在因素。     

Site of graviperception in roots: a re-examination

Two lines of evidence have been cited to support the assertion that the root cap is the sole site of graviperception in the root. The first evidence is based on surgical removal of the cap, which abolishes the response to gravity. This is sufficient to conclude that the cap is involved in gravitropism, but not to conclude that the cap is the site of graviperception. The second is based on the results of centrifugation experiments, in which different parts of the plant are subjected to different centrifugal forces. The data from such experiments have been cited to support the conclusion that the perception of gravity is limited to the rootcap. However, these data actually support the conclusion that gravity is perceived throughout the root tip, and not only in the root cap. We believe that the data support the conclusion that the root cap is involved in root gravitropism, but that there is inadequate evidence to conclude that the cap is the sole site of graviperception.     

Discrete three-stage population model: persistence and global stability results

A general three-stage discrete-time population model is studied. The inherent net reproductive number for this model is derived. Global stability of the origin is established provided that the inherent net reproductive number is less than one. If it is larger than one the existence of a unique positive fixed point is proved and the persistence of the system is established. Finally, for certain parameter ranges global stability of the positive fixed point is proved.     

扬子鳄视觉器官组织学研究

本文用光镜和电镜研究了扬子鳄(Alligator sinensis)的组织学,同时测量了其眼球的一些光学参数.扬子鳄眼球呈扁圆球形,角膜径与球径的比值为1:1.44;晶状体与角膜的比值为1:1.40。角膜内具鲍氏膜;虹膜内的括约肌、睫状体内的睫状肌均属横纹肌,视细胞椭圆体内线粒体嵴突与线粒体长轴相平行,这与报道的其它鳄类不同。虹膜内未见扩瞳肌纤维,角膜缘缺巩膜小骨片,晶状体环垫薄,因而其视觉调节能力仍然很弱。视网膜中视细胞由视杆细胞、单锥细胞、双锥细胞组成,其中以视杆细胞占多数。视细胞与神经节细胞核比值平均为2.5:1,表明扬子鳄的组织结构与其弱光视觉相适应。     

羚牛(Budorcas taxicolor)部分脏器特点的观察

本文对2只羚牛的雌性生殖器官及肝、肾、脾等脏器进行了形态描述,并与黄牛及羊的相应器官进行了比较,为探讨羚牛的分类地位提供了解剖学资料。     

短柄五加大,小孢子发生和雌,雄配子体发育的研究

短柄五加花药５枚,每个花药四个花粉囊。小孢子母细胞减数分裂时,胞质分裂为同时型,产生正四面体形的四分体。花药壁由表皮、药室内壁、中层和绒毡层四层细胞组成,其发育类型为双子叶型。腺质绒毡层,其细胞为二核。三细胞型花粉。子房５室,每室两个胚珠,上胚珠败育,下胚珠可育。下胚珠倒生,具单珠被,厚珠心。大孢子母细胞减数分裂形成线性排列的四个大孢子,雌配子体发育属蓼型。开花当天,花粉散开,雌配子体尚未成熟,处     

Visual and buying sequence features-based product image recommendation using optimization based deep residual network

A recommendation system is an imaginative resolution for managing the restrictions in e-commerce services with item details and user details. Also, it is used to determine the user preferences to recommend the items they expected to buy. Several conventional collaborative filtering techniques are devised in the recommender model, but it has some complexities. Hence, an innovative optimization-driven deep residual network is devised in this paper for a product recommendation system. Here, the product of images is used for extracting features where the Convolutional neural network (CNN) features are computed, and then it is given as input to the deep residual network aimed at product recommendation. The deep residual network is trained using developed Elephant Herding Feedback Artificial Optimization (EHFAO), which is obtained by integrating Elephant Herding optimization (EHO) into the Feedback Artificial Tree (FAT). Here, the item grouping is carried out on input data based on K-means clustering. After item grouping, Cosine similarity is used to perform matching of groups, where the best group is acquired among all the available groups. Extraction of list of visitors is done from the best group. Then, the list of items is obtained from the sequence of best visitor. Next, the corresponding binary sequence is obtained for the applicable sequence of visitor. From this sequence of best visitor, the recommended product is acquired. Then, the recommended product is subjected to the sentiment analysis for which the score is determined. Here, the sentiment analysis helps to decide whether the product is recommended or not recommended. If the score is positive, then the same product is recommended; otherwise, the new product is recommended. The proposed EHFAO-based deep residual network attained better performance in comparison to the other techniques with a maximal F-measure at 84.061%, 84.061% precision, 87.845% recall along with minimal Mean Squared Error (MSE) of 0.216.     

黑鸢消化系统形态学的初步研究

对黑鸢消化系统的形态学作了初步的观察与研究,结果表明：黑鸢舌尖钝圆,舌根分叉,叉粘膜上具有尖端指向后方的栉状突;食管宽而扁,无明显可见的嗉囊;肌胃无明显的类角质膜;肠道长是体长2．3倍,小肠较发达,K1275mm,古肠道总长的93．6％,具有不发达的双侧盲肠：胰腺短而厚、并与蛇雌、毛脚鸢的消化系统进行了比较。     

从姜黄中提取姜黄素的研究

本文利用75％乙醇浸提姜黄得到姜黄素粗提物,然后分别采用吸附分离法和沉淀法对粗提物进一步分离提纯得到纯度较高的姜黄素产品。在吸附分离法提取姜黄素实验中,考察了不同洗脱剂组成对洗脱率的影响,实验发现90％乙醇洗脱效果最好;在沉淀法实验中,考察了不同pH值条件下的姜黄素沉淀量,发现pH值为7．0时,姜黄素沉淀量最大。实验结果表明,沉淀法得到的姜黄素产品纯度比吸附分离法得到的高,但沉淀法产品收率比吸附分离法低,吸附分离法比沉淀法更适合工业应用。     

The taxonomy and biology of further aeolidacean and arminacean nudibranch molluscs with symbiotic zooxanthellae

The occurrence of symbiotic zooxanthellae in further aeolid and arminacean nudibranch molluscs is described for the first time. The aeolid Aeolidiopsis ransoni Pruvot-Fol is redescribed, and a new species of Aeolidiopsis , also feeding on the colonial zoantharian Palythoa , is described. Both have symbiotic zooxanthellae. The taxonomy of the family Aeolidiidae is discussed and the genus Berghia Trinchese, 1877 is considered a synonym of Spurilla Bergh, 1864. Spurilla major (Eliot, 1903) and a new species of Spurilla are reported to have zooxanthellae while another new species of Spurilla is without zooxanthellae. The glaucid aeolid Pteraeolidia ianthina (Angas) is shown to have symbiotic zooxanthellae, as is the arminacean Doridomorpha gardineri Eliot, which is reported to feed on the alcyonarian blue coral, Heliopora. In all cases, the morphological adaptations developed for this symbiosis are described. Further notes on the Porites-fetding arminacean Pinufius rebus Marcus & Marcus and the aeolid Phestilla lugubris (Bergh) are included and a facultative symbiosis with zooxanthellae is suggested for the latter. The tion of symbiosis with zooxanthellae within nudibranchs is discussed and it is suggested that the relationship has evolved independently on several occasions.     

The consequences of dominance and gene flow for local adaptation and differentiation at two linked loci

For a subdivided population the consequences of dominance and gene flow for the maintenance of multilocus polymorphism, local adaptation, and differentiation are investigated. The dispersing population inhabits two demes in which selection acts in opposite direction. Fitness is determined additively by two linked diallelic loci with arbitrary intermediate dominance (no over- or underdominance). For weak as well as strong migration, the equilibrium structure is derived. As a special case, a continuous-time continent–island model (CI model) is analyzed, with one-way migration from the continent to the island. For this CI model, the equilibrium and stability configuration is obtained explicitly for weak migration, for strong migration, for independent loci, and for complete linkage. For independent loci, the possible bifurcation patterns are derived as functions of the migration rate. These patterns depend strongly on the degree of dominance. The effects of dominance, linkage, and migration on the amount of linkage disequilibrium (LD) and the degree of local adaptation are explored. Explicit formulas are obtained for $D$   $(=x_1{x}_4-x_2{x}_3)$ and $r^2$ (the squared correlation in allelic state). They demonstrate that dominant island alleles increase $D$ and decrease $r^2$. Local adaptation is elevated by dominance of the locally adaptive alleles. The effective migration rate at a linked neutral locus is calculated. If advantageous alleles are dominant, it is decreased only slightly below the actual migration rate. For a quantitative trait that is determined by two additive loci, the influence of dominance on measures of differentiation is studied. Explicit expressions for $Q_{ST}$ and two types of $F_{ST}$ at equilibrium are deduced and their relation is discussed.     

The effect of gene flow on the coalescent time in the human-chimpanzee ancestral population

The coalescent process in the human-chimpanzee ancestral population is investigated using a model, which incorporates a certain time period of gene flow during the speciation process. a is a parameter to represent the degree and time of gene flow, and the model is identical to the null model with an instantaneous species split when a=infinity. A maximum likelihood (ML) method is developed to estimate a, and its power and reliability is investigated by coalescent simulations. The ML method is applied to nucleotide divergence data between human and chimpanzee. It is found that the null model with an instantaneous species split explains the data best, and no strong evidence for gene flow is detected. The result is discussed in the view of the mode of speciation. Another ML method is developed to estimate the male-female ratio (alpha) of mutation rate, in which the coalescent process in the ancestral population is taken into account.     

香樟、枸树主茎水分传导能力分布研究

本文从植物生长发育的机理发出,从理论推导出植物主茎传导能力与主茎长度、导管长度的关系式,导管越长,榈传导能力越大,香樟主茎长度大于１８ｃｍ、枸树大于１２ｃｍ时,传导能力随样品长度线笥变化;较知时,传导能力随样品长度的缩短迅速增加,出现短路现象。试验测定了香樟、枸树主茎水分长距离运输的传导能力分布,结果与理论预示的安全一致,表明理论分析是正确可靠的,这一规律具有普遍意义。     

Vanadate-stimulated NADH oxidation in plasma membrane

The rate of NADH oxidation with oxygen as the acceptor is very low in mouse liver plasma membrane and erythrocyte membrane. When vanadate is added, this rate is stimulated 10- to 20-fold. The absorption spectrum of vanadate does not change with the disappearance of NADH. The reaction is inhibited by superoxide dismutase, and there is no activity under an argon atmosphere. This indicates that oxygen is the electron acceptor and the reaction is mediated by superoxide. The vanadate stimulation is not limited to plasma membrane. Golgi apparatus and endoplasmic reticulum show similar increase in NADH oxidase activity when vanadate is added. The endomembranes have significant vanadate-stimulated activity with both NADH and NADPH. The vanadate-stimulated NADH oxidase in plasma membrane is inhibited by compounds, which inhibit NADH dehydrogenase activity: catechols, anthracycline drugs and manganese. This activity is stimulated by high phosphate and sulfate anion concentrations.     

大黄鱼精子的超微结构

大黄鱼的精子由头产和尾部两部分组成。头部结构较为独特,其腹侧有一较大的细胞核,背部有中心粒复合体。头部的后端是袖套。细胞核的腹面稍向外突出背面则稍向内凹。细胞核中的染以质浓缩成致密的团块状。团块状的染色质之间分布着松散的纤维状染色质。植入窝位于细胞核的背部表面,由细胞核背面向内凹陷而成,呈一沟状,其走向与精子的长轴平行。