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1.
The following procedure for staining Negri bodies in sections is based on methods previously described by MacNeal, by Haynes, and by Richter:

Fixation:
  1. 1. Zenker's solution 4 hours at 37°C or Dominici's 3 hours.

  2. 2. 70% alcohol, 12 to 18 hours at room temperature.

  3. 3. 80% alcohol, about 5 to 6 hours.

  4. 4. 90% alcohol, about 4 to 6 hours.

  5. 5. Absolute alcohol about 16 hours.

  6. 6. Ether and absolute alcohol aa, about 8 hours.

  7. 7. 16 to 24 hours in the following mixture: celloidin 1 g., methyl salycilate 25 cc., abs. alcohol 25 cc., ether 25 cc.

  8. 8. Chloroform and paraffin, 2 to 3 hours.

  9. 10. Paraffin, 1 to 1 1/2 hours.

  10. 11. Embed.

staining:
  1. 1. Cut sections 4 to 5 μ.

  2. 2. Bring section to water and cover with Lugol's iodine for 10 minutes.

  3. 3. Decolorize with a 2% sodium thiosulfate (hypo).

  4. 4. Wash thoroly with water.

  5. 5. Cover with a mixture of equal parts of 0.5% phloxine and 1% eosin Y (National Aniline brand) and leave for 15 minutes.

  6. 6. Wash with water and stain 2 to 5 minutes in 0.1% azure B (National Aniline).

  7. 7. Wash with 96% alcohol and decolorize in a mixture of 2 parts absolute alcohol with 1 part clove oil, ordinarily for not more than 1/2 to 1 minute.

  8. 8. Dehydrate rapidly, clear, and mount in Yucatan Elemi.

  相似文献   

2.
3.
Riassunto

L'A. ha studiato l'embriogia della Vinea difformis Pourr. ed ha potuto stabilire che:

  1. l'archisporio è pluricellulare e possono svilupparis talvolta pi[ugrave] cellule madri;

  2. normalmente solo una cellula madre arriva a maturità;

  3. delle quattro megaspore solo una è fertile e precisamente la pi[ugrave] calazale;

  4. lo sviluppo del gametofito è del tipo Normale cioè Monomegasporiale con oangio emisporiale.

Ha inoltre risontrato una anomalia di sviluppo constituita da un gametofito binucleato abnorme per ritardo delle divisioni nucleari cispetto all'acerescimento che è quello di un gametofito ottonucleato.  相似文献   

4.
5.
Gallic acid acts as a precursor molecule to synthesize various tannin molecules. These are plant polyphenols and were proved to be good anti-oxidant, anti-cancerous, anti-inflammatory, anti-microbial compounds. In order to fully exploit prominent biological activities of specific tannins and to develop tannin-based new medicines, it is necessary to obtain their pure preparations with an aim of high yield and specificity. In the present study, gallic acid is synthesized by the hydrolysis of tannic acid using a microbial based transformation process. The microorganism was isolated and identified. The ability of the isolated microorganism to covert tannic acid into gallic acid was determined by HPLC and enzyme production.
  • Highlights
  • The present investigation signifies the role of Enterobacter spp. in various processes:

  • ??To synthesize gallic acid (a precursor for food oxidant such as propyl gallate) and a bacteriostatic antibiotic (trimethoprim).

  • ??To protect the environment from tannery’s discharge through the process of biodegradation.

  • ??To reduce the toxicity of tannins in animal feed.

  相似文献   

6.
The quantitative determination of sarcosine is of great importance in clinical chemistry, food and fermentation industries. Elevated sarcosine levels are associated with Alzheimer, dementia, prostate cancer, colorectal cancer, stomach cancer and sarcosinemia. This review summarizes the various methods for quantitative analysis of sarcosine with special emphasis on various strategies of biosensors and their analytical performance. The current bio sensing methods have overcome the drawbacks of conventional methods. Sarcosine biosensors work optimally at pH 7.0 to 8.0 in the linear range of 0.1 to 100?μM within 2 to 17?s and between 25 and 37?°C, within a limit of detection (LOD) between 0.008 and 500?mM. The formulated biosensors can be reused within a stability period of 3–180?days. Future research could be focused to modify existing sarcosine biosensors, leading to simple, reliable, and economical sensors ideally suited for point-of-care treatment.
  • Clinical significance
  • Elevated sarcosine levels are associated with prostate and colorectal cancer, Alzheimer, dementia, stomach cancer and sarcosinemia.

  • Quantitative determination of sarcosine is of great importance in clinical chemistry as well as food and fermentation industries.

  • Attempts made in development of sarcosine biosensors have been reviewed with their advantages and disadvantages, so that scientist and clinicians can improvise the methods of developing more potent sarcosine biosensor applicable in multitudinous fields.

  • This is the first comprehensive review which compares the various immobilization methods, sensing principles, strategies used in biosensors and their analytical performance in detail.

  相似文献   

7.
Summary

The Author studies the action of the presence of the ear and its parts in the growth of the stem and in the value of the water of traspiration and of assimilation in the higher leaf. The stet shows:

  1. A removed ear, not yet mature, exerts a depressing effect upon the development of the stem and ucon the leaf's functions.

  2. The threads and the pistils removed inhibit the enlongament of the stem and alter the functions of leaves.

  3. Maturing seeds removed cause trubles on the function of the vegetative organ.

This phenomen is due to the presence of an hormonical substances elaborated in the riproduction's orgas, which are considerated the centre of functional correlation.  相似文献   

8.
Abstract

The Influence of Short Periods of Lighting with Different Wavelengths on the Orcadian Changes of the Enzymatic Digestive Activities in Palaemon serratus (Crustacea, Natantia)

The effect of light on the circadian rhythms of digestive activities in the Shrimp Palaemon serratus have been studied.

  1. Continuous darkness leads in a few days to a disappearance of the variations of the circadian rhythms of digestive enzymes while these rhythms go on in continuous light.

  2. Short (1 or 2 hrs) and low intensity flashes of white light are effective in bringing on the reappearance of rhythmic variations in darkness.

  3. We have been able to establish an isoquantic spectrum of action of the light. Two values of wavelength appears to account for a maximum sensibility of the shrimp: one in ultraviolet light and an other one, more important, in the green (λ=544 nm).

  4. In green light it is possible to obtain the same effect of light by decreasing the time of stimulation to 5 or 10 mn and in increasing the total quantity of energy. Significant responses are obtained with total energy greater than 10000 pE. cm‐2.

  相似文献   

9.
  1. The catalase activity of Candida tropicalis pK 233 was induced by hydrocarbons but not by glucose, galactose, ethanol, acetate or lauryl alcohol.

  2. The induction of the catalase activity depending upon hydrocarbons was sensitive to cycloheximide but not to chloramphenicol.

  3. Glucose repressed strongly the induction of the catalase activity by hydrocarbons but galactose did not affect seriously.

  4. When C. tropicalis was incubated with hydrocarbons, the appearance of microbodies was observed electronmicroscopicaliy.

  相似文献   

10.
Inmunoglobulin isolated from human sera, be it by the cryo-alcohol, rivanol, multi membrane electrodecantation or polyethylene glycol process, alvays contains denatured material. This may result from the influence either singly or in combination, of acme of the follwing factors:
  1. inefficiency of the purification procedure;

  2. surface denaturation;

  3. imperfect freeze-drying of the final product; and

  4. factors yet unknown vhich cause alteration in the immoglobulins or other protein components not ellminated by the purification procedures.

  相似文献   

11.
The nutritional values of nonessential amino acids as the nitrogen source in the crystalline amino acid diet for the chick growth were examined. The nitrogen of the nonessential amino acids in the basal diet for chick was substituted for a nonessential amino acid to be tested on the nitrogen base. The experimental methods were the same as in the evaluation of the nutritional value of d-amino acids previously reported. Nonessential amino acids were classified into four groups.
  1. Very useful nitrogen source: Glutamic acid, Aspartic acid

  2. Useful nitrogen source: Alanine, Diammonium citrate

  3. Insufficient nitrogen source: Glycine, Proline

  4. Harmful for chick growth: Serine

At the end of experiment chicks were killed and the concentration of free amino acids in the serum were measured. The concentration of glycine and serine in the serum increased when glycine was tested, but that of serine in the serum only increased when serine was tested. This result suggested the pathway from glycine to serine was fast and the opposite one was very slow.  相似文献   

12.
  1. l-Aspartate was found to replace l-asparagine in the protective action from acid inactivation of l-asparaginase (EC 3.5.1.1) produced by Escherichia coli A–1–3 and at the same time to inhibit the proteolytic inactivation by α-chymotrypsin.

  2. l-Asparaginase changed in its chromatographic properties in the presence of l-aspartate and became to be absorbed on the CM Sephadex column.

  3. The sedimentation patterns of l-asparaginase at pH 3.5 were identical either in the presence or absence of l-aspartate, showing partial dissociation. But the reversibility to the active state was observed only in the enzyme dissolved in the solution containing l-aspartate.

  4. l-Aspartate did not prevent the enzyme either from the dissociation into subunits or from decrease in the activity by urea.

  5. High concentration of l-aspartate was shown to inhibit the l-asparagine hydrolysis reaction.

  6. l-Aspartate was suggested from ORD measurements to cause changes in the higher structure as well as the ionic properties or proteolytic inactivation.

  相似文献   

13.
Abstract

Inactivation and riactivation of enzymes in endosperms of castor bean seeds. — On the basis of previous results, the possibility has been investigated of the reversible interconversion of active and inactive form of enzymes in castor bean seeds, during their development.

The results described here indicate that:

  1. the activity of some glycolytic enzymes increases greatly (81% and 400% increase of, respectively, Gl-6-P-dehydrogenase and aldolase) upon incubation of dry seeds for few hours at 4 °C.

  2. The decrease of enzyme activity upon dehydration of seeds and the increase during the subsequent imbibition can be shown reproducibly.

  3. This same observation is made for oxygen uptake.

These results are interpreted to indicate the reversible inactivation of enzymes caused by dehydration of seeds.  相似文献   

14.
Using a total of 43 craneological data obtained from any of 73 vicugna and 25 alpaca skulls, three problems were analyzed:
  • Identification of skulls

  • Taxonomic situation of the vicugna

  • Origin of the alpaca.

For rapid identification of New World cameloid skulls it is recommended to use the condilobasal length, the length to heigth ratio and the presence of the Fissura nasolacrimalis.

Some characteristics of the skulls considered essential for the evaluation of domestication processes exclude the vicugna from the alpaca's ancestors.  相似文献   

15.
Abstract

We have developed an improved and effective method to immobilize lipase on hydrophobic polyurethane foam (PUF) with different modifications. PUF was treated with hydrochloric acid to increase the active sites and then the active carboxyl groups and amino groups were exposed. Enzyme activity of lipase immobilized on PUF-HCL (8000?U/g) was 50% higher than that of lipase immobilized on PUF (5300?U/g). There is an increase in the activity of the immobilized lipase on AA/PEI-modified support (115,000?U/g), a 2.17-fold increase compared to lipase immobilized on the native support was observed. The activity of immobilized lipases was dependent on the PEI molecular weight, with best results from enzyme immobilized on PUF-HCL-AA/PEI (MW 70,000?Da, 12,800?U/g)), which was 2.41 times higher compared to that of the same enzyme immobilized on PUF. These results suggest that the activity of immobilized lipase is influenced by the support surface properties, and a moderate support surface micro-environment is crucial for improving enzyme activity. Finally, the immobilized lipase was used for the production of vitamin A palmitate. The immobilized lipase can be reused for up to 18 times with a conversion rate above 90% for 12?h in a 3?L bioreactor.
  • Research highlights
  • An efficient immobilization protocol on polyurethane foam was developed

  • Polyethyleneimine and acetic acid were used to regulate the micro-environment concurrently

  • The activity of lipase immobilized on PUF-HCL-AA/PEI was improved by 2.41 times

  • Immobilized lipase exhibited excellent operational stability for vitamin A palmitate synthesis

  相似文献   

16.
Summary

The Author studies with the weighing method the action of plant-eater insects on the alteration of the substances fresch and dry in the hust leaves and he comes to the following conclusions:

  1. The fresh substance stand less alterations in the leaves with the excavated border than in the sound leaves, the dry substance is less in the hust leaves than in those sound.

  2. The fresh substance shows little waverigs in the leaves notched on alone side of the border, but the dry substance is always inferior in the hust leaves than in the sound half and in those entire.

  3. The substances fresh and dry are less in the bored leaves than in the sound, the dry substance shows little alternations in those bored in one or the other half of the border.

This would indicate that the traumatic action of insects causes in the leaves a depresson of the cellular swuelling, whih determines a bigger mobilization of the dry substanc's elements than in the sound leaves.  相似文献   

17.
Summary

In order to study a side of the influence of ultra-violet light on plants, the A. has harvested, 10 days after fertilisation, 1040 plants of Triticum vulgare Vill. and made many groups of them; then he sheared differently the ears and screened them partially from light so as to obtain, from the same subject, treated and untreated grains. Such ears he treated for different times of exposure with the light of a quarzlamp giving almost only ultra-violet rays. For the present, are here reported only results concerning the influence of ultra-violet light upon both germinating energy and power:

  • ultra-violet light stimulates the germinating power of grains, born from subjects treated no longer than 240 hours at a distance of 1 m from the lamp; longer treatments abate germinating power;

  • ultra-violet light stimulates, the germinating energy of grains born from subjects treated no longer than 120 hours; treatments during 120–240 hours don't notably modify it; treatments of over 240 hours reduce it very much;

  • according to the conditions in which this work has been done, a 10 days-irradiation seems to be, under every point of view, for the best. A 71/2 — days irradiation seems to be insufficient, a 121/2 — days one excessive, and hence prejudicial;

  • glumes are strong screening-organ for ultra-violet light;

  • ultra-violet light gives late appearing effects.

Since great difficulties usually occur whenever tests such as the present one are undertaken, the A. proposes some leading ways to previously settle the U.V.-rays dosimetry fit for every plant, in order to avoid wast of time and to get data of general value.  相似文献   

18.
In Fortführung seiner Untersuchungen über neotropische Acanthocinini veröffentlicht der Verfasser hiermit Beschreibungen von folgenden neuen Gattungen:
  • Nyssodrysilla nov. gen. mit N. irrorata (Melzer) aus Brasilien als Generotype, N. viliata (Melzer), comb, nov., aus Brasilien und N. lineata nov. spec, aus Peru.

  • Nyssodrysola nov. gen. mit N. stictica nov. spec. aus Peru als Generotype.

  • Sciadosurus nov. gen. mit S. albobrunneus nov. spec. aus Peru als Generotype.

  • Acarinozineus nov. gen. mit A. striatus nov. spec. aus Peru als Generotype und A. spinicornis nov. spec, aus Mexiko.

  • Alcathousites nov. gen. mit A. chaclacayoi nov. spec. aus Peru als Generotype.

  • Xylergatina nov. gen. mit X. pulcher (Lane) aus Peru als Generotype.

  • Xylergatoides nov. gen. mit X. asper (Bates) aus Brasilien und Argentinien als Generotype.

Ferner werden revidiert die Gattungen:
  • Xylergates Bates, Generotype X. lacteus (Bates), mit Beschreibung der beiden neuen Arten X. elaineae aus Peru und X. dorotheae aus Britisch‐Guayana.

  • Chaetanes Bates, Generotype C. setiger (Bates), mit Beschreibung der drei neuen Arten C. costulatus aus Peru, C. nigrobasalis aus Brasilien und C. apicalis aus Französisch‐Guayana.

  • Wo es erforderlich ist, sind Bestimmungstabellen gebracht und die Arten abgebildet.

  相似文献   

19.
SUMMARY

It is nearly sixty years since the first studies were undertaken on the nutrient chemistry of African lakes. There have been numerous studies on the chemical composition of African waters in the intervening years. Yet as recently as five years ago it was stated that little was known about nutrient cycling in lakes. Nutrient ‘species’ simply formed an additional list compiled along with lists of species of algae, zooplankton, aquatic plants and fish. A spate of monographs, papers and reports in recent years, however, has begun to fill some of the gaps in our knowledge of nutrient cycling in African lake ecosystems. This paper reviews the recent literature of nutrients in African lakes from the point of view of nutrient sources, in-lake nutrient kinetics and nutrient sinks, with particular reference to nitrogen and phosphorus, and their cycling rates into and out of various biotic and abiotic compartments. The principle conclusions that can be drawn from the review are as follows:

  1. Allochthonous inputs, particularly in terms of external nutrient loading, have been relatively well-studied in recent years, but little is known of autochthonous nutrient inputs, despite numerous observations that nutrient regeneration is likely to be substantial in African lakes.

  2. The rôle of microbial processes in nutrient cycling in African lakes is almost totally unknown, except in relation to nitrification and denitrification.

  3. Recent studies have begun to examine the kinetics of the uptake of phosphorus by algae in African lakes; nitrogen uptake, other than nitrification, and nutrient release have only rarely been examined.

  4. Nutrient uptake and release by aquatic macrophytes is reasonably well known, especially in the ‘nuisance’ weed species.

  5. The role of zooplankton, zoobenthos and fish in nutrient cycling in African lakes has largely been ignored.

  6. A great deal of study has been devoted to the rôle of abiotic process, particularly at the sediment-water interface, in the nutrient dynamics of African lakes.

As yet, little emphasis has been placed on inter-compartmental exchanges in studies on nutrient cycles but it would appear that these processes are now beginning to receive attention and, as nutrient cycling in African lake ecosystems becomes better known, research will tend toward a more numerical approach.  相似文献   

20.
Abstract

This study evaluated remediation of the herbicide sulfentrazone in soils with three different mineralogies (kaolinite, hematite, and gibbsite) and three remediation sulfentrazone treatments (Canavalia ensiformis L., Crotalaria juncea L., and natural attenuation). This study was conducted in a factorial scheme, in triplicate with randomized block design. Sulfentrazone was applied at 0 and 400?g ha?1. We analyzed sulfentrazone residue in the soils by high-performance liquid chromatography and confirmed the results with bioassays of Pennisetum glaucum. Herbicide movement was greater in the kaolinitic soil without plant species. The retention of herbicide in the kaolinitic soil occurred in larger quantities in the 0–12?cm layer, with higher levels found in the treatments with plants. In the hematitic soil with C. juncea, all applied herbicides were concentrated in the 0–12?cm layer. In the other hematitic soil treatments, sulfentrazone was not detected by chemical analysis at any soil depth, although in many treatments, it was detected in the bioassay. Phytoremediation was more efficient with C. ensiformis grown in gibbsitic soil, reducing the sulfentrazone load by approximately 27%. Natural attenuation was more efficient than phytoremediation in oxidic soils due to soil pH and texture soils favored microbial degradation of the compound.
  • Highlights
  • The influence of soil mineralogy of herbicide sulfentrazone retention was evaluated.

  • Canavalia ensiformis and Crotalaria juncea were evaluated as phytoremediation plants.

  • Kaolinite soils presented great movement of sulfentrazone in the soil.

  • Natural attenuation is more efficient in oxide soils than phytoremediation.

  相似文献   

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