Showing papers by "Cairo University published in 1973"

Use of aloe iim treating leg ulcers and dermatoses

Abstract: The use of aloe species for healing by man dates back to tliousands of years before the Christian age. Aloe vera, known by the ancient Egyptians, was described in the Ebers papyrus. Drawings of the plant found on the walls of ancient Egyptian temples sliow that its pul}^ was used externally for treatment of burns, ulcers and parasitic infections of the skin. Hippocrates described aloe vera and its medicinal uses.̂ t Aloe has been used by the Arabs many centuries for the treatment of wounds.\"* It was a popular remedy for various diseases in China several thousands of years ago. It is reported that Alexander the Great used aloe gel extensively.^ A species of aloe was referred to in the Bible (John 19:39). Many species of aloe are currently recognized in various pharmacopoeias, namely Aloe perryi Baker, Aloe vera linni {Aloe barbadensis Miller), Aloe spicala Baker, Aloe ferox Lamarck, and Aloe Africana Miller.2. fi. î , is However, limited chemical, pharmacological and clinical research data on aloe have been recorded in the literature. It has been used with some success in the treatment of various dermatological condiions,i3 radiation ulcers,''-1\"'̂ internal diseases such as peptic ulceri and btu'ns.'' There are reports on its use for cosmetic

Reactions with the Arylhydrazones of some α-cyanoketones

Abstract: Ethereal diazomethane reacts with the arylhydrazones of mesoxalic acid dinitrile 1a–c and of ethyl α-cyanoglyoxalate 2b, d–g to yield the methylarylhydrazones 3a–c and 4a–e respectively. Treatment of 4b–e with phenylmagnesium bromide results in the formation of the imino derivatives 5a–d. Whereas 2a–g react with phenylhydrazine to yield the aminopyrazoles 8a–g, the hydrazides 10a, b are formed on treatment of 4c, e with hydrazine hydrate. 1a–c react with hydrazine hydrate and with phenylhydrazine to yield 3-amino-4-arylhydrazono-5-imino-2-pyrazoline derivatives 11a–f11a, b react with acrylonitrile to yield 3-amino-1(β-cyanoethyl)-4-arylhydrazono-5-imino-2-pyrazoline derivatives 12a, b which can be readily cyclised to the pyrazolo[3,2-b]pyrimidine derivatives 13a, b by the action of hot acetic acid.

General Field Theory Treatment of H-Plane Waveguide Junction Circulators

Abstract: In this paper an exact field theory treatment for the waveguide junction circulators is presented. The treatment is general, being dependent on neither the geometrical symmetry of the junction nor the number of ports. The electromagnetic fields in the joining waveguides are written in the form of infinite summation of waveguide modes. The solutions of the wave equations in the ferrite rod and in the surrounding air are obtained in the form of infinite summation of cylindrical modes. The fields at the ferrite air interface and at an imaginary boundary chosen arbitrarily between the air region and the waveguides are then matched. This process leads to an infinite system of nonhomogeneous equations in the field amplitudes. Three types of waveguide junction circulators using this technique are analyzed: the simple ferrite-rod Y junction, the simple ferrite-rod T junction, and the latching Y junction. Point-matching techniques are used to get numerical results for the field distributions and the circulator characteristics. Excellent agreement has been found between the published experimental measurements and the numerical results obtained by this technique.

Eco-physiological studies on desert plants : VIII. Root penetration of Leptadenia pyrotechnica (Forsk.) Decne. in relation to its water balance

Abstract: 1. Leptadenia pyrotechnica (Forsk.) Decne. is a leafless tree growing under, adverse arid conditions in the valleys of the Eastern Desert in Egypt. 2. The plant cover in areas inhabited by this species is very low and amounts to only 1% in some localities. In such an open vegetation competition between roots is lacking and each root system monopolizes a huge volume of soil. 3. The root system of a small Leptadenia bush penetrates to a depth of 11.5 m and has a lateral extension of 10 m. The root system exploits about 850 m3 of soil. The distribution of the roots and their branching is closely related to the availability of the soil moisture in the different strata. 4. The available soil moisture is not uniform throughout the whole profile. Depending on the average available soil moisture at the different depths, the total available moisture in the soil volume occupied by the root system of Leptadenia bush is found to be about 23000 kg. 5. The annual water output by the studied bush is found to be 5700 kg. This means that the available water in the soil occupied by the root system is sufficient to supply the plant for a period of four years without replenishment by rainfall. 6. The present study shows that the plant can live safely for several years under the severe conditions of the desert. The plant possesses some characteristics which help it to keep its water balance positive through increased absorption.

Habitat features and vegetation of deserts and semi-deserts in egypt

Abstract: Egypt forms the north-eastern corner of Africa and embraces a total area of almost exactly a million square kilometres. Desert conditions prevail throughout the country, and the population of nearly 34 millions is mainly concentrated in an area of some 355oo sq. kin. The cultivated area amounts to about 25oo sq. km. Without the Nile, Egypt would be the harshest desert all over the world. The Nile traverses the country from south to north for a distance of 15oo kin. A glance to the map of Egypt (Fig. I), with the cultivated lands coloured green and the deserts in shades of brown, will show that the cultivated land has the shape of a lotus plant. The Nile represents the stem, the Delta is the flower and Fayioum depression is the bud. Egypt, due to its peculiar situation, has been considered to belong to more than one floral region. The northern coastal region adjacent to the Mediterranean sea belongs to the Mediterranean region and forms a natural extention of the Algerian-Tunisian flora. While the major part of the country belongs to the African-Indian desert region. Relics of the western and central Asiatic flora are met with in Sinai. In the southeastern corner of Egypt viz. Gebel Elba, the flora of the Sudanese Park Steppe is found. Egypt occupies a key position between the Asiatic and African continents, and its floristic composition shows affinities in different directions.

The functional morphology of Haemaphysalis spiracles (Ixodoidea: Ixodidae).

Abstract: The spiracular structure of Haemaphysalis hoodi, H. kinneari, H. punctata, H. longicorms, and Boophilus microplus is described as seen by light and scanning electron microscopy (SEM), and is discussed in relation to previous reports on the structure and function of tick spiracles. Surface pores and a prominent lip-guarded ostium in the spiracular plate are readily observed by SEM and also in histological sections. Goblets in the peripheral part of the spiracular plate open to the exterior by pores and connect the hypodermal epithelium with fine canals apparently containing sensory sensilla. Experimental CO2 and cyanide gas exposure provide evidence of a mechanism for opening and closing the spiracle and involving the ostial lip and atrial valve. This mechanism appears to depend on hemolymph pressure and action of atrial and other body muscles.

Studies on 1,2,4‐triazine derivatives. III. The Behaviour of some Derivatives of 1,2,4‐Triazine toward diazomethane, amines, ethyl monobromoacetate and tetra‐O‐acetyl‐α‐D‐glucopyranosyl bromide

Abstract: The reaction of diazomethane with 6-phenyl-3-thioxo-5-oxo-2,3,4,5-tetrahydro-1,2,4-triazine 2a, and with 6-phenyl-3-methylmercapto-5-oxo-4,5-dihydro-1,2-triazine 3a effected N-methylation to 2b and 3b, respectively. Compound 3a and 3-methyl-mercapto-5, 6-diphenyl-1,2,4,-triazine 4a react with amines to give 3-N-substituted-amino-triazines 5a–h and 6a–h, respectively. 3-Mercapto-5,6-diphenyl-1,2,4-triazine 4b underwent S-alkylation with ethyl monobromoacetate and with tetra-O-acetyl-α-D-glucopyraosyl bromide.

Revision ofFagonia species (Zygophyllaceae) with tri- to unifoliolate and simple leaves

Abstract: A taxonomical revision of3Fagonia groups, viz. the complexes ofF. arabica, F. bruguieri andF. indica, including the interrelationships between their species, is presented. These complexes are characterized by their compound tri- or reduced unifoliolate leaves. Among the truly simple-leaved species, viz.F. socotrana, F. harpago andF. ovalifolia, the confusion betweenF. socotrana and some other taxa described is considered. The different patterns of the leaf trace of simple and compound tri- to unifoliolate leaves may prove to be of systematic value.

Intermittent trifascicular block: Different mechanisms of conduction disturbances in the bundle branches

Abstract: Analysis of the electrocardiograms of a patient with acute anterior wall myocardial infarction revealed the development of fixed left anterior hemiblock and tachycardia-dependent intermittent conduction in the left posterior branch and right bundle branch systems, with a higher critical rate for conduction in the former system. The electrocardiograms provided a classic illustration of this type of trifascicular block. Both grade I and type I (Mobitz) blocks of atrioventricular (A-V) conduction are attributed to conduction disturbance in the left posterior branch system. The distinction made between the functional nature of type I (Mobitz) block and the organic nature of type II block is criticized especially in the presence of a bundle branch block pattern. Failure of conduction of 3 consecutive impulses in the left posterior branch system, shown in some tracings, is attributed to 3 different electrophysiologic mechanisms: (1) conduction through an incompletely repolarized posterior branch due to pathologic prolongation of its functional refractory period (phase 3 block); (2) enhanced phase 4 depolarization (phase 4 block); and (3) retrograde activation of the posterior branch by an impulse traveling down the right bundle. Regular alternation of the second and third mechanisms occasionally gave rise to long periods of consistent block in the posterior branch. Other tracings demonstrated that successful conduction in the posterior branch could perpetuate transmission failure in the right bundle through retrograde activation of the right bundle branch system. The value of deductive analysis in unraveling complex disturbances of the cardiac rhythm is illustrated.