一种植物生长激素-N'-(5-硝基-2-羟基苯亚甲基)-3,5-二羟基苯甲酰肼的合成、晶体结构和抗菌活性

目的:合成并表征一种属于植物生长激素的席夫碱类化合物.方法:由5-硝基水杨醛和3,5-二羟基苯甲酰肼在甲醇溶液中反应得到N′-(5-硝基-2-羟基苯亚甲基)-3,5-二羟基苯甲酰肼.结果:用单晶X-射线衍射法测得其结构并表征,同时通过抗菌实验证明其在一定浓度下具有明显的抗菌活性.结论:这种席夫碱类化合物在某种程度上具有明显的抗菌活性.     

Multipurpose Intensive Care Unit in a District General Hospital

The advantages of a four-bedded purpose-built general intensive care unit in a district general hospital are described. In addition to 1,447 inpatients treated between January 1968 and December 1971 the unit was used to conduct outpatient investigations. This has filled an important gap in conventional arrangements, and is practical and economical. The unit has proved to have advantages, not only for seriously ill patients but also has benefited the hospital in other ways. It has been of material assistance in recruiting and training nursing and medical staff and has been welcomed and supported by patients and their relatives. It has also attracted practical support from voluntary organizations whose generosity has enabled much additional equipment to be purchased.     

一些小麦白粉病抗源抗性基因鉴定分析

研究鉴定了我国３７份小麦白粉病抗源的抗性基因,１９份材料不具有任何抗性基因;６份材料具有来自１ＢＬ／１ＲＳ易位系的抗性基因Ｐｍ８;５份材料具有抗性基因Ｐｍ５ａ;３份分别具有对目前欧洲所有生理小种均抗的抗性基因Ｐｍ２１、Ｐｍ１６和Ｐｍ１２;４份材料具有新的抗性基因。     

Purification and substrate specificity of BcmI restriction endonuclease

A strain producing the new specific restriction endonuclease BcmI has been found in the Bacillus generum. The enzyme has been purified by chromatography on the blue sepharose, phosphocellulose PII, heparin sepharose. The analogous purification has been obtained when the blue sepharose has been substituted for the orange sepharose, the home produced sorbent. The BcmI enzyme has been shown by the substrate specificity definition to be an isoschizomer of the restriction endonuclease ClaI.     

Ivermectin 20 years on: maturation of a wonder drug

Ivermectin has been on the veterinary market for almost a quarter of a century and has been approved for human use for 18 years. Its use has revolutionized the treatment of nematode and arthropod parasites in animals and has provided hope for the control or even eradication of filariases in humans. Although much remains to be learned about how the drug works and how resistance to it will develop, it has earned the title of "wonder drug".     

Prejudice and tolerance in a period of increasing ethnic diversity and growing unemployment: Denmark since 1970

Abstract

Since the end of the 1960s Denmark, once an ethnically homogeneous country, has become more heterogeneous as a result of immigration by foreign workers and refugees. The question is how has this development influenced the attitudes in Denmark towards immigrants? The saliency of the immigrant issue has certainly grown, but contrary to expectations, the level of ethnocentrism has changed very little. If anything, the Danish population has become less prejudiced and more tolerant during the last thirty years. This conclusion, based on a number of national surveys, is even more conspicuous as the level of unemployment has increased in the same period.     

Binding specificity of a HeLa DNA-binding protein to DNA and homopolymers

A protein which has affinity for single-stranded DNA but not for double-stranded DNA has been isolated from HeLa cells by DNA-cellulose chromatography. This protein having a molecular weight of 34,000 was accounted for approximately 3% of total soluble proteins. Its binding specificity to DNA and nucleotide homopolymers has been investigated by Sephadex G-200 column chromatography. Specific binding to single-stranded DNA has been confirmed also by this method and furthermore strong binding to poly U has been found.     

The unidirectional flagellar motor of Rhodobacter sphaeroides WS8 can rotate either clockwise or counterclockwise: characterization of the flagellum under both conditions by antibody decoration.

A variant of Rhodobacter sphaeroides WS8 has been isolated which when tethered has a cell body that rotates counterclockwise instead of clockwise. Antibody decoration in vivo has shown that the filament on the variant has handedness opposite to that of the normal form. In both cases the cell body is pushed by the rotating flagellum.     

三维重建在口腔解剖生理学教学中的应用*

口腔解剖生理学是口腔专业重要的基础课程,本学科理论知识内容复杂,实践操作技能要求高,给老师和初学者在教与学的过程中带来很大的压力。本学科自开课以来一直在探讨选择最佳的教学方法,随着计算机图像技术的不断完善,CT三维重建也随之问世,颌面部三维重建模型,逼真形象,便于操作和理解,大大降低了学习难度,显著提高了教学质量,取得相当客观的效果。     

Transmission acoustic microscopy of tissue sections (1 GHz). Histoacoustics and acoustic staining

The acoustic microstructure of mouse small intestine has been studied with a transmission acoustic microscope working at 1 GHz and the influence of the histologic processing on the microacoustic pattern has been tested. Unstained thin sections provide pictures rich in details and highly contrasted. Gelatin has been used as hydrosoluble embedding medium and has been compared to paraffin. The former embedding procedure retained the viscoelastic properties of the specimen far more and provided the most detailed pictures. Osmiun tetroxide has been used to demonstrate acoustic staining.     

Transmission acoustic microscopy of tissue sections (1 GHz)

Summary The acoustic microstructure of mouse small intestine has been studied with a transmission acoustic microscope working at 1 GHz and the influence of the histologic processing on the microacoustic pattern has been tested. Unstained thin sections provide pictures rich in details and highly contrasted. Gelatin has been used as hydrosoluble embedding medium and has been compared to paraffin. The former embedding procedure retained the viscoelastic properties of the specimen far more and provided the most detailed pictures. Osmiun tetroxide has been used to demonstrate acoustic staining.     

Sensitivity of the rabbit embryonal Leydig cells to the action of different pituitary hormones

Leydig cells reaction of rabbits testis to choriogonin action has been investigated during the prenatal period of ontogenesis. It has been found, that these cells sensitivity to the hormones studied has been detected at the early stages of embryogenesis. The specialization of Leydig cells response to choriogonin, thyrotrophin and prolactin in the process of prenatal period has been shown.     

Structural and functional aspects of the heart ventricle myoglobin of bluefin tuna

The heart ventricle myoglobin of bluefin tuna has been purified to an apparent homogeneity. The amino acid analysis has revealed only a limited number of substitutions between the myoglobins of yellowfin and bluefin tuna. The alpha-helix content of tuna myoglobin has been found considerably lower than that of mammalian myoglobin. No correlation has been discovered between the conformational stability and alpha-helix content. Denaturation experiments have shown that the whole structure of tuna myoglobin results from the interaction of two structural units which represent the product of independent folding processes. The structure of tuna myoglobin has been found more open and disorganized than that of sperm whale. This result has been related to the low content of electrostatic interactions and explained in terms of evolutive adaptations.     

Novel alpha- and omega-conotoxins from Conus striatus venom.

Three neurotoxic peptides from the venom of Conus striatus have been purified, biochemically characterized, and chemically synthesized. One of these, an acetylcholine receptor blocker designated alpha-conotoxin SII, has the sequence GCCCNPACGPNYGCGTSCS. In contrast to all other alpha-conotoxins, SII has three disulfide bonds (instead of two), has no net positive charge, and has a free C-terminus. The other two paralytic peptides are Ca channel-targeted omega-conotoxins, SVIA and SVIB. omega-SVIA is the smallest natural omega-conotoxin so far characterized and has the sequence CRSSGSPCGVTSICCGRCYRGKCT-NH2. Although omega-conotoxin SVIA is a potent paralytic toxic in lower vertebrate species, it was much less effective in mammals. The third toxin, omega-conotoxin SVIB, has the sequence CKLKGQSCRKTSYDCCSGSCGRSGKC-NH2. This peptide has a different pharmacological specificity from other omega-conotoxins previously purified from Conus venoms; only omega-conotoxin SVIB has proven to be lethal to mice upon ic injection. Binding competition experiments with rat brain synaptosomal membranes indicate that the high-affinity binding site for omega-conotoxin SVIB is distinct from the high-affinity omega-conotoxin GVIA or MVIIA site.     

The effect of oligomycin on rat liver mitochondria respiring in state 4

It has been found that oligomycin inhibits up to at least 50% state-4 mitochondrial respiration. A time dependence of oligomycin inhibition has been shown. A titration curve for state-4 respiration of sigmoidal profile has been presented. The possibility of misreading this oligomycin effect, so far never reported, has been excluded by evaluating the quality of mitochondrial preparations used in respect to their morphological, functional and electrochemical properties. The conclusion has therefore been put forward that the most part of respiration in steady-state-4 is driven by ATP synthesis.     

Characteristics of Symmetric Surface Plasmon Polariton Mode in Glass–Metal–Glass Waveguide

The propagation characteristics of symmetric surface plasmon polariton mode in a glass–metal–glass waveguide are presented. Gallium lanthanum sulfide has been taken as the glass and silver (Ag) has been used as the metal. The analysis has been done both numerically and analytically. A two-dimensional finite-difference time-domain-based simulation model has been developed in order to analyze the propagation characteristics numerically. The obtained results using numerical and analytical methods have been compared and a very good agreement has been found.     

An archeozoological analysis of teeth of lower jaw of pigs coming from the Kostolac culture (3,250-3,000 B.C.), originating from Vucedol,including comparison with recent

An investigation has been made within the expertise regarding teeth of 10 left halves of mandibles of recent sows as well as teeth of 18 pig mandibles originating from Kostolac culture (3,250-3,000 B.C.) from Vucedol archaeological location. TWS (Tooth Wear Stage) has been determined at all molars, according to Grant method and a corresponding numerical equivalent has been added, so MWS (Mandibular Wear Stage) has been obtained by summing up the above. On the basis of these values and ranges of MWS, an approximate age at the time of death has been determined for each unit. All the recent units have been older than 17 months, while the age of Kostolac units has come out to be between 14 and 17 months.