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1.
W. Blake Christensbn 《Biotechnic & histochemistry》1949,24(3):165-170
Albert's method, of staining diphtheria cultures consists of staining a fixed smear for one minute (some laboratories stain for five minutes) with a solution containing toluidine blue and malachite (or methyl) green, washing with water, and applying Albert's iodine for one minute. This procedure is discussed and criticized, and in addition the mechanism of the stain is elucidated. Also, the procedure which involves staining a fixed smear for one minute with Loeffler's alkaline methylene blue solution is discussed and criticized.
To overcome the objections to the above staining methods, a different method is proposed. This consists of staining a fixed smear with an acid solution of toluidine blue, washing with water, applying Albert's iodine for one minute, washing with water, and finally applying a safranin solution for 15-20 seconds. The theoretical basis for this method is presented. 相似文献
To overcome the objections to the above staining methods, a different method is proposed. This consists of staining a fixed smear with an acid solution of toluidine blue, washing with water, applying Albert's iodine for one minute, washing with water, and finally applying a safranin solution for 15-20 seconds. The theoretical basis for this method is presented. 相似文献
2.
Robert Blake II Elizabeth A. Shute James Waskovsky Arthur P. Harrison JR. 《Geomicrobiology journal》2013,30(3-4):173-192
Abstract Microorganisms capable of aerobic respiration on ferrous ions are spread throughout eubacterial and archaebacterial phyla. Phylogenetically distinct organisms were shown to express spectrally distinct redox‐active biomolecules during autotrophic growth on soluble iron. A new iron‐oxidizing eubacterium, designated as strain Funis, was investigated. Strain Funis was judged to be different from other known iron‐oxidizing bacteria on the bases of comparative lipid analyses, 16S rRNA sequence analyses, and cytochrome composition studies. When grown autotrophically on ferrous ions, Funis produced conspicuous levels of a novel acid‐stable, acid‐soluble yellow cytochrome with a distinctive absorbance peak at 579 nm in the reduced state. Stopped‐flow spectrophotometric kinetic studies were conducted on respiratory chain components isolated from cell‐free extracts of Thiobacillus ferrooxidans. Experimental results were consistent with a model where the primary oxidant of ferrous ions is a highly aggregated c‐type cytochrome that then reduces the periplasmic rusticyanin. The Fe(II)‐dependent, cytochrome c‐catalyzed reduction of the rusticyanin possessed three kinetic properties in common with corresponding intact cells that respire on iron: the same anion specificity, a similar dependence of the rate on the concentration of ferrous ions, and similar rates at saturating concentrations of ferrous ions 相似文献
3.
M.S. Blake K.H. Johnston G.J. Russell-Jones E.C. Gotschlich 《Analytical biochemistry》1984,136(1):175-179
A rapid, sensitive method has been developed to detect antibody-antigen complexes on “Western blots.” The methods of H. Towbin, T. Staehlin, and J. Gordon were used to separate and blot the antigens onto nitrocellulose. The remaining sites of attachment were blocked and the nitrocellulose was washed with polyoxyethylenesorbitan monolaurate (Tween 20). The blot was then reacted with the antiserum or hybridoma supernate to be tested. After the antigen-antibody reaction was completed, the blot was washed and treated with anti-antibody which has been conjugated to alkaline phosphatase. The alkaline phosphatase was detected by the reduction of the tetrazolium salt to diformazan by the hydrogen ions released in the formation of indigo by the reaction of the phosphatase on the indoxyl phosphate. The advantages of this method over previously described techniques are (1) use of Tween 20 allows the blot to be stained with Coomassie blue, (2) the substrates of the alkaline phosphatase reaction are stable for long periods of time, (3) the reaction products form an intense blue color which does not fade, (4) the resolution is extremely good with little to no band broadening, (5) the reaction is sensitive to picogram quantities of antigen, and (6) the reaction is quantitative. 相似文献
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J Blake D M Helmeste C H Li 《International journal of peptide and protein research》1985,25(6):575-579
Two analogs of human beta-endorphin (beta-EP) which contain cystine bridges, [Cys15-Cys26,Phe27,Gly31]-beta-EP (I) and [Cys16-Cys26,Phe27,Gly31]-beta-EP (II), were synthesized by the solid-phase method. Peptides I and II were shown to contain 2-2.5 times the opiate receptor binding activity of beta-endorphin. We also synthesized two analogs with reduced alkylated cysteine residues and these peptides, [Arg9,19,24,28,29 Cys(Cam)11,26,Phe27,Gly31] and [Arg9,19,24,28,29,Cys-(Cam)12,26,Phe27,Gly31], were shown to have approximately the same opiate receptor activity as beta-endorphin. 相似文献
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Experiments are described which were designed to investigate the significance of individual differences in aggressiveness between polecats and the relation between the familiarity of the opponent and the pattern and outcome of fighting.
The behaviour of Mustela putorius, M. furo and hybrids between the two species was investigated in an indoor arena of 16 m2 .
Two kinds of fighting between male polecats were recorded, "companion fighting" between cage mates, in which biting was inhibited and neither of the opponents became intimidated and "uninhibited fighting" between unfamiliar individuals from which a winner and loser generally emerged and a rank order formed.
Individual differences in aggressiveness were assessed by means of a scoring system which statistical analysis showed, generally, to be consistent for any one individual. The rank of an animal, however, was found not to be invariably related to its aggression score.
A number of other factors influencing fighting were investigated, the earlier introduction of one individual into the arena increases its chances of winning a fight; when offered a choice, male polecats fight strangers in preference to cage mates; and the separation of a group of cage mates for as little as 48 hours induces them to behave towards one another like strangers with the result that a rank order is formed. Factors which had no apparent effect on fighting between males were the weight of the individual or the presence of females.
The attributes of familiar and unfamiliar opponents are discussed in the light of these findings. 相似文献
The behaviour of Mustela putorius, M. furo and hybrids between the two species was investigated in an indoor arena of 16 m
Two kinds of fighting between male polecats were recorded, "companion fighting" between cage mates, in which biting was inhibited and neither of the opponents became intimidated and "uninhibited fighting" between unfamiliar individuals from which a winner and loser generally emerged and a rank order formed.
Individual differences in aggressiveness were assessed by means of a scoring system which statistical analysis showed, generally, to be consistent for any one individual. The rank of an animal, however, was found not to be invariably related to its aggression score.
A number of other factors influencing fighting were investigated, the earlier introduction of one individual into the arena increases its chances of winning a fight; when offered a choice, male polecats fight strangers in preference to cage mates; and the separation of a group of cage mates for as little as 48 hours induces them to behave towards one another like strangers with the result that a rank order is formed. Factors which had no apparent effect on fighting between males were the weight of the individual or the presence of females.
The attributes of familiar and unfamiliar opponents are discussed in the light of these findings. 相似文献
10.
We investigated the reason for the high mortality we had observed in hypophysectomized-orchidectomized Golden Syrian hamsters that were anesthetized with intraperitoneal (i.p.) injections of chloral hydrate (CH). Intact male Golden Syrian hamsters were injected intraperitoneally with 0.1cc/100g BW of a 35% solution of CH, a 35% solution of sodium chloride, or double-distilled water. Equal numbers of hamsters in each group were injected on the right or left side of the abdomen. Within 10 days, 35% of the CH-injected hamsters were dead or had to be euthanized. Autopsy revealed severe peritonitis and adynamic ileus. CH-injected hamsters that survived gained weight at a rate similar to that of the controls. All surviving hamsters were killed 18 days after the injections. Among the surviving CH-injected hamsters, 84.6% had intra-abdominal adhesions, 61.5% had unilateral testicular atrophy, and 53.8% had a yellowish necrotic mass in the epididymal fat pad (EFP). All the lesions occurred on the side that was injected. The atrophied testes had been rendered cryptorchid due to involvement with intra-abdominal adhesions. In the water-treated controls, there were no abnormalities; whereas, in the saline controls, 75% had a mass in the EFP. Histology of the EFP mass was similar in hamsters injected with CH or hypertonic saline and suggested a diagnosis of fat necrosis. The results suggest that the mortality, the intra-abdominal adhesions, and the unilateral cryptorchidism were caused by a single i.p. injection of CH, but the fat necrosis in the EFP was probably caused by high concentrations of salt. The results further suggest that high concentrations of CH should not be injected intraperitoneally for anesthesia in chronic studies, particularly of the male reproductive system. 相似文献