中蜂越夏及秋季繁殖试验

在贵州锦屏进行的中蜂越夏及秋繁试验表明，４框以上的群势越夏较为安全。越夏期间每框足蜂约需补喂白糖１．５公斤。越夏后，蜂群群势约下降１／３左右。蜂群在越夏期间飞逃的主要原因是缺蜜及巢虫危害。当地中蜂在秋季大流蜜初期发生分蜂，分蜂群势均为８框足蜂以上，７框左右不分群。为控制不同起繁群势的蜂群在秋季大流蜜初期正好繁殖到７框左右，不致因分蜂影响秋冬蜜的采集，应分期起步秋繁。根据本试验所建秋季起繁群势（ｘ）与达７框群势所需繁殖天数（ｙ）之间的回归直线方程推算，在起繁群势为１～５框蜂量时，最适的秋繁开始期，１框群为７月３１日，２框群８月１０日……蜂群的基础群势每增加一框，则秋繁开始期应相应推迟１０～１１天。     

Transfer of chlorinated hydrocarbon insecticides and polychlorinated biphenyls from particles to membranes studied by quenching of fluorescence

Hydrophobic chlorinated hydrocarbons are adsorbed onto particles in the environment. Thus, uptake of chlorinated hydrocarbons into organisms is likely to be from the particle-adsorbed state. We investigated the transfer of chlorinated hydrocarbons from particles to phospholipid membranes, quantified by quenching of the fluorescence of a carbazole-labeled phospholipid which was used to label the membranes. The chlorinated hydrocarbons studied included DDT, DDE, methoxychlor, lindane, stirofos, and several polychlorinated biphenyls. The particles studied were porous glass, kaolinite, cellulose, and silica. Transfer of chlorinated hydrocarbons from particles to vesicles was independent of the chlorinated hydrocarbon concentration. The transfer rate did not depend on binding of lipids to particles, and was independent of the lipid composition of the vesicles. Membrane uptake of chlorinated hydrocarbons from the particle-adsorbed state was more rapid than uptake from the microcrystalline state, and uptake was faster when the chlorinated hydrocarbons were dispersed over larger particle surface areas. The transfer rates of chlorinated hydrocarbons correlated with their aqueous solubilities. In total, these results indicate that chlorinated hydrocarbons are transferred through the aqueous phase. We judge the rate-limiting step in membrane uptake to be the rate of solubilization of the chlorinated hydrocarbons from the particles into the bulk aqueous phase. Adsorption of chlorinated hydrocarbons onto particles may enhance the transfer rate by dispersing the chlorinated hydrocarbons and making them more available for solubilization in the bulk aqueous phase. The data are correlated with a model that assumes diffusion across an unstirred aqueous layer which interfaces with the bulk aqueous phase and the particle.     

Serum and abomasal antibody response of sheep to infections with Haemonchus contortus

Serum and abomasal IgA, IgG and IgM antibody response against adult worm, L3 and egg antigens of Haemonchus contortus was monitored by the ELISA technique after one or two infections with this nematode. Following the first infection, antibody levels in serum did not change materially. After administration of a challenge dose of infective larvae, antibodies of the three immunoglobulin classes in infected animals rose slightly, but this rise appeared later than the fall in the faecal egg counts. In contrast, in abomasal mucosa, IgA anti-larval antibody levels, which did not increase materially after the primary infection, rose rapidly after a transient inhibition when sheep were challenged. A close temporal relationship was observed between the rise in local anti-worm IgA antibodies and the self-cure reaction, but antibody levels fell rapidly after worm diminution. The local antibody response was thus considered to be related to immunity of sheep to H. contortus.     

中国确立沉默权制度是大势所趋

沉默权是现代法治国家刑事司法制度的一项重要内容，它体现了对犯罪嫌疑人、被告人人格尊严和自由意志的尊重，为其充分行使辩护权提供程序上的保证，反映一个国家刑事诉讼法律制度的文明与进步状况，被认为是‘人类通向文明的斗争中最重要的里程碑”之一。本文主要介绍了沉默权的内涵、我国确立沉默权制度的必要性和可行性，并对如何建立符合我国国 情的沉默权制度提出若干建议。     

Effect of Sowing Date on the Yield of Lentil (Lens culinaris Medik.)

A sowing date experiment was conducted over 6 years (1978–1983) to determine the optimum sowing date for lentil on vertisols in Debre Zeit area, Ethiopia. The results showed that sowing between the last week of June and the second week of July maximizes lentil yield. Later planting after mid-July, reduced both yield and time to maturity.     

Fine structure and invasive behaviour of the early developmental stages of Theileria annulata in vitro

The interaction, in vitro, between bovine peripheral blood lymphocytes and sporozoites of Theileria annulata (Ankara) was studied by light and electron microscopy. Beginning five minutes following incubation, samples were taken for Giemsa-stained smears and glutaraldehyde-fixed pellets, for light and electron microscopy, respectively. Sporozoites of T. annulata measure an average of 0.9 microns long, 0.8 microns broad and possess a limiting unit membrane, the pellicle; a round-to-ovoid, eccentrically situated, non-chromocentric nucleus; double-membraned, tubular, acristate mitochondria; varying numbers of anisocytic, densely osmiophilic and pleomorphic organelles, the rhoptries which together with the polar ring form the apical complex; and numerous, loosely scattered, electron-dense ribosomal particles. As early as 5 min of incubation, sporozoites had made contact with, and penetrated, lymphocytes. Sporozoites consistently attached to the lymphocyte plasmalemma by their basal end, possibly at specific receptor sites. Apparently only a proportion of lymphocytes (up to 40% and more commonly 10-20%) were susceptible. Two subpopulations of the susceptible lymphocytes were observed; one which appeared to have receptor sites localized on one pole of the plasmalemma and the other subpopulation in which the receptor sites were distributed evenly around the plasmalemmal surface. Within individual susceptible lymphocytes, the number of interiorized sporozoites increased from 1 to 3 at 5-10 min to as many as 15 or more parasites at around 60 min of incubation. Theileria annulata sporozoites were interiorized by the invagination of the host cell plasmalemma which remained intact throughout the process but later fragmented. Within 30 min of interiorization, each sporozoite underwent dedifferentiation by the loss of its rhoptries and transformed into a trophozoite. Around 24 h, the trophozoite, a uninucleate, motile and feeding stage of the parasite, developed into a schizont by an acentric, closed mitosis.     

In vitro properties of diffuse cytoplasmic esterase-positive canine mononuclear leukocytes

Depletion of cytoplasmic esterase-positive canine peripheral blood monocytes from mononuclear cell suspensions was attempted using plastic adherence, carbonyl iron ingestion and/or Sephadex G-10 filtration. An esterase-positive, nonadherent, nonphagocytic subpopulation was identified and further characterized by the presence or absence of cell membrane receptors for the Fc portions of immunoglobulin and the activated third component of complement. The majority of these nonadherent cells lacked these receptors. The data suggests that canine peripheral blood monocytes are a heterogenous cell population.     

极早熟丝瓜早冠的选育

早冠丝瓜是以H-04为母本，H-02为父本配制而成的一代杂交种，极早熟，第一雌花节位着生于主蔓第4-7节，从定植至始收30天左右，前期产量1500-2000kg/667m^2，总产量4500-6000kg/667m^2。     

The effects of dl-tetramisole and rafoxanide on tricarboxylic acid cycle enzymes of Haemonchus contortus, in vitro

Various enzymes of the tricarboxylic acid cycle (TCA) viz., aconitase (E.C. 4.2.1.3), isocitrate dehydrogenase (E.C. 1.1.1.42), succinate dehydrognease (E.C. 1.3.99.1), fumarate reductase (NADH: fumarate oxido-reductase), fumarase (E.C. 4.2.1.2) and maltate dehydrogenase (E.C. 1.1.1.37) were detected in adult Haemonchus contortus (Nematoda: Trichostrongylidae), in vitro. Low activities of aconitase and isocitrate dehydrogenase suggested that the TCA cycle has a minor function and the pathway of CO₂ fixation is the major pathway in the energy metabolism of the parasite. In vitro incubation in Tyrode's solution had no significant effect on TCA cycle enzymes and the worm was able to maintain normal metabolism for 12 h.The effects of dl-tetramisole and rafoxanide on various enzymes of the TCA cycle were studied in adult H. contortus. At 50 μg ml^?1 varying degrees of succinate dehydrogenase and fumarate reductase activities were observed. At the same concentration, the activities of other enzymes remained unaltered.     

Distribution of Serotypes of Group-B Streptococci in Herds and Cows Within an Area of Denmark

During a 3-year period strains of Group-B streptococci from 1227 (94.6 %) of a total of 1297 cases of bovine mastitis were serologically typed. Twenty-seven different antigenic combinations were found. Ab. 70 % of the strains carried polysaccharide antigens among which Type III was predominant (57 %). The protein antigen X was widespread (62 %), and 5 % of the strains were non-type able.Type Ic predominated among “false positive” bulk milk isolates (52.2 %, 12/23), but was rarely isolated from quarter milk samples (3%).Variation in the antigenic structure of infecting strains occurred to some extent and involved at least 10.8 % (132/1227) and probably 25.2 % (132/523) of the strains. Within a herd the antigenic variation was limited, however. Hence a definition of a herd type was possible. During the period of investigation infections caused by Herd Type III decreased numerically while the number of herds infected by other types remained almost stable.