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Showing papers by "Cairo University published in 1987"


Book ChapterDOI
TL;DR: In this paper, the chemistry and biological properties of pyrazolopyrimidines and pyrazolo[3,4-d]pyrimidine were discussed. But the authors focused on theoretical methods, spectra, and tautomerism.
Abstract: Publisher Summary The interesting biological activities reported for pyrazolopyrimidines have stimulated chemists to develop the chemistry of this class of compounds. This chapter appears to be the first survey of the chemistry and biological activity of this class of compounds. Condensation of β-keto esters with 3( 5)-aminopyrazoles has been used extensively to synthesize pyrazolo[ 1,5-a]pyrimidines. Theoretically, two isomeric pyrazolo[ 1,5-a] pyrimidines can be produced. The parent pyrazolo pyrimidine has been synthesized via cyclocondensation of 1-unsubstituted 3(5)-aminopyrazoles (12) with malonodialdehyde tetramethylacetate. This approach was used to synthesize several substituted pyrazolo pyrimidines. 3- Oxoalkanonitriles and their functional derivatives condense readily with 12 to yield 7-aminopyrazolo. And benzoylacetonitrile and its p-chlorophenylazo and acetylbenzyl cyanide derivatives react with β-cyanoethylhydrazine (74) to yield pyrazolo pyrimidines formed via l-β-cyanoethyl-5-aminopyrazole intermediates. The chapter also discusses chemical properties of pyrazolo[ 1,5-a]pyrimidines and pyrazolo[3,4-d]pyrimldines and elaborates on theoretical methods, spectra, and tautomerism.

112 citations


Journal ArticleDOI
A.B. Elwishy1
TL;DR: The breeding season in the camel appears to be longer than was previously thought, and the presence of a large and well developed CL which is maintained throughout pregnancy can be a valuable tool for assessing early pregnancy in camels.

72 citations


Journal ArticleDOI
TL;DR: The essential oil of the oleogum resin "Olibanum" was prepared by direct steam distillation as well as by steam distilled of an N-hexane extract as mentioned in this paper.
Abstract: The essential oil of the oleogum resin "Olibanum" was prepared by direct steam distillation as well as by steam distillation of an N-hexane extract. Physical and chemical constants of the oil were determined. GC-MS was used for the analysis of the oil. Thirty-three components were identified in the steam distilled oil by their Kovats indices on stabilized OV-1 columns and by mass spectral data. The oil contains 62.1% esters, 15.4% alcohols, 9.9% monoterpene hydrocarbons, and 7.1% diterpenes. Certain minor constituents of the steam distilled oil failed to show up in the oil prepared by steam distillation of the N-hexane extract. Both oils exhibit antimicrobial activity, the activity of the steam distilled oil being higher than that of the oil prepared by steam distillation of the N-hexane extract.

65 citations


Journal ArticleDOI
TL;DR: The philosophy is to be aware of the amount and direction of variation for a particular landmark, which will enable the orthodontists to look on their cephalometric numbers with a mental awareness of the possible variations.

55 citations


Journal ArticleDOI
Ahmed Shafik1
TL;DR: The communicating veins, identified between the hemorrhoidal and vesical plexuses, offer an explanation for the vague pathologic aspects of recurrent bacteriuria, urethral discharge, cervicitis, and vaginitis, and provide a proper line for their treatment.
Abstract: A review of the new concepts of the anatomy of the anal sphincter mechanism and the physiology of defecation is presented. The external sphincter is a triple-loop system; each loop can function as a separate sphincter through voluntary inhibition action and mechanical compression. Stress defecation resulting from internal sphincter damage is described. A new technique for repair of rectal incontinence is presented, which depends on inducing continence not only by mechanical compression, but also by voluntary inhibition. The mechanism of defecation and rectal continence is described and four types of incontinence presented. Also, the mechanism of both the levator dysfunction syndrome and prolapse is demonstrated and a technique of repair is presented. The study defines two types of rectal anomalies; suprahiatal and infrahiatal. The role of the embryonic anorectal sinus, anorectal band, and epithelial debris in the genesis of perirectal suppuration, chronic anal fissure, pruritus ani, and hemorrhoids is described. The communicating veins, identified between the hemorrhoidal and vesical plexuses, offer an explanation for the vague pathologic aspects of recurrent bacteriuria, urethral discharge, cervicitis, and vaginitis, and provide a proper line for their treatment. They also serve to perform a new radiographic technique--anal cystography--and to administer drugs, including chemotherapeutics, in the treatment of pelvic malignancies.

49 citations


Journal ArticleDOI
TL;DR: In this paper, the behavior of 2-amino-3-cyano-4H-pyran derivatives toward a variety of nucleophilic reagents is reported.

47 citations


Journal ArticleDOI
Armed Shafik1, A. Moftah1, S. Olfat1, M. Mohi-el-Din1, Adly H. El-Sayed1 
01 Jun 1987-Urology
TL;DR: The anatomy of the testicular veins of 42 male cadavers were studied to determine the extent of their role in varicocelogenesis and other pathologic conditions and the results are presented.

47 citations


Journal ArticleDOI
M. Kassas1
TL;DR: In this article, the authors argue that drought does not necessarily cause desertification, but that the actions of mankind do, and that desertification is bound to continue in the absence of effective policy, planning and development.

36 citations


Journal Article
Tawfik Hn1
TL;DR: It is indicated that other factors also play a role in the induction of tumors that are enhanced by the schistosomal infection, and urine cytology as a screening tool is effective in detecting early bladder cancer.
Abstract: Carcinoma of the urinary bladder is the most common malignancy in Egyptians. At the National Cancer Institute in Cairo, it accounts for 27.6% of all cancers--38.5% of cancers in the male and 11.3% in the female. This very high frequency is attributed to underlying schistosomiasis. The infection can lead to malignancy through local tissue damage, mechanical irritation, bilharzial toxins or through secondary bacterial infection. Bacterial products include nitrate reductase capable of synthesizing nitrosoamines and beta glucuronidase enzymes, active at pH 7. Through liver involvement and dysfunction, tryptophan metabolism is disturbed, with the excretion of carcinogenic metabolites. Vitamin A deficiency is responsible for the squamous metaplasia and the high frequency of squamous cell carcinoma observed in the bladder. The characteristic clinico-pathological features of cancer of the urinary bladder are outlined, mainly the occurrence at a young age, the male predominance, especially farmers, and the high association with schistosomiasis. The tumors are often first seen in an advanced stage, arising from the posterior bladder wall and vault. The trigone is only affected in 8.5% of the cases. Histologically, squamous cell carcinomas of low grade are the most frequent cell type. Lymph node involvement is low in spite of the advanced stage of the tumor. Therefore, the results of radical surgery are encouraging. The results of a special study correlating the above parameters with the intensity of ova deposition are presented. Patients with heavy infection at a slightly earlier age but other tumor parameters the same are similar to those of egg-negative cases. This study indicates that other factors also play a role in the induction of tumors that are enhanced by the schistosomal infection. In Fayoum Province, schistosomiasis is decreasing while bladder cancer is increasing. Urine cytology as a screening tool is effective in detecting early bladder cancer. Studies are now in progress to detect tumor associated antigens in sera and urine of patients.

34 citations


Journal ArticleDOI
TL;DR: In this paper, VC membrane electrodes were used to select tetracycline (TC), doxycycline (DC), and oxytetracycine (OTC) for antibiotic applications.

32 citations


Journal ArticleDOI
TL;DR: It is suggested that, in vivo, during change of posture from recumbent to erect, collapse of the IJV occurs and increases the resistance to blood flow in it, which acts as a natural self-regulating antisiphon device, which counteracts the effect of gravity and regulates the pressure above the vein.
Abstract: The internal jugular vein (IJV) of an adult human cadaver was used to study the effect of its behavior as a collapsible tube in regulating its upstream pressure. The results suggested that the resistance to flow in the IJV varies according to changes in its contour, which occur as a result of changes in its transmural pressure. This suggested that, in vivo, during change of posture from recumbent to erect, collapse of the IJV occurs and increases the resistance to blood flow in it. The increase in the resistance to blood flow acts as a natural self-regulating antisiphon device, which counteracts the effect of gravity and regulates the pressure above the vein, i.e., in the sigmoid sinus and, consequently, the intracranial pressure, within narrow limits, regardless of the position of the individual.

Journal ArticleDOI
TL;DR: Three four-week-old calves were used in a study on serological responses in combined Sarcocystis cruzi and Toxoplasma gondii infections and reacted as expected regarding the general antibody responses to the S cruz and T gondius infections.

Journal ArticleDOI
TL;DR: Alkylation of 5-cyano-4-oxo-6-phenyl-2-thioxo-1,2,3,4-tetrahydropyrimidine I with methyl iodide, chloroacetic acid or 3-chloro-2,4 -pentanedione, afforded the S-alkyl derivatives IIa-c. 2-Carboxymethylthio and 2-(2′,4′-dioxopentan-3-ylthio) derivatives IIb and IIc could be cyclised by

Journal ArticleDOI
TL;DR: In this article, the activation energy of the conduction mechanism and log ϱ27°C increase with increasing cadmium content, which affects the exchange interaction mechanism in tetrahedral (A) sites and octahedral (B) sites.
Abstract: Polycrystalline samples of mixed ferrite Mnl −xCdxFe2O4, wherex = 0, 0.2, 0.4, 0.6 and 0.8, were studied by X-ray analysis and d.c. electrical conductivity. lt was found that the calculated lattice parameter (a0) increases from 0155 to 0.861 nm according to increases inx from 0 to 0.8. The apparent density and theoretical density exhibit the same behaviour. lt was also found that the activation energy of the conduction mechanism and log ϱ27° C increase with increasing cadmium content, which affect the exchange interaction mechanism in tetrahedral (A) sites and octahedral (B) sites.

Journal ArticleDOI
TL;DR: In this paper, the dissolution behavior of an anodized niobium electrode in NaOH solutions was investigated as a function of alkali concentration, formation voltage, formation current density and temperature using potential and impedance measurements.
Abstract: The dissolution behaviour of the anodized niobium electrode in NaOH solutions was investigated as a function of alkali concentration, formation voltage, formation current density and temperature using potential and impedance measurements The rate of dissolution is dependent on the alkali concentration In dilute NaOH solutions (1 N) the anodic oxide film formed in 05 M H2SO4 is reasonably stable On the other hand, at higher concentrations of NaOH (≥2 M), the anodized electrode is subject to continuous dissolution depending on the alkali concentration Also, the dissolution process is considerably affected by temperature; at temperatures greater than 320 K the oxide film is destroyed in less than 30 min The results show that the current density used during the formation of the oxide film has no effect on its dissolution rate

Journal ArticleDOI
TL;DR: It was concluded that the physiologically correct way of shunting the CSF to the IJV is against the direction of blood flow.
Abstract: An experimental model for shunting the cerebrospinal fluid (CSF) to the internal jugular vein (IJV) using a valveless shunting catheter was used in two experiments to study the differences between shunting the CSF either in or against the direction of blood flow. The results of the first experiment suggested that: if the CSF is shunted to the IJV in the direction of blood flow, the intracranial pressure (ICP) will stabilize at a lower level than the venous pressure (VP); blood will regurgitate into the shunting catheter during periods of rise in the intrathoracic pressure (ITP) and during change of posture from erect to recumbent; siphonage will develop when the erect posture is assumed and will lead to CSF overdrainage and intracranial hypotension; the flow of CSF to the venous circulation will be intermittent. The results of the second experiment suggested that: if the CSF is shunted to the IJV against the direction of blood flow, the ICP will stabilize at a higher level than the VP; blood will not regurgitate into the shunting catheter during periods of rise in the ITP or during changes in posture; siphonage will not develop in the erect posture; the flow of CSF to the IJV will be continuous, and its rate will be equal to and dependent on the rate of CSF formation. It was concluded that the physiologically correct way of shunting the CSF to the IJV is against the direction of blood flow.

Journal ArticleDOI
TL;DR: New pyrazolo[1,5-a]pyrimidines, pyrano[2,3-c]pyrazoles and Pyrano[3,4-c]-pyrazole were synthesised by reaction of the α,β-unsaturated nitriles 1, 13 and 16 with 3-amino-2-pyrazolin-5-one (2), 1-phenylpyrazolidine-3, 5-dione (5), and 5-aminimally-polyphenyl pyrazole (10)
Abstract: New pyrazolo[1,5-a]pyrimidines, pyrano[2,3-c]pyrazoles and pyrano[3,4-c]pyrazoles were synthesised by reaction of the α,β-unsaturated nitriles 1, 13 and 16 with 3-amino-2-pyrazolin-5-one (2), 1-phenylpyrazolidine-3,5-dione (5), and 5-amino-3-phenylpyrazole (10). Nitrile in der Heterocyclen-Synthese: Synthese einiger neuer Pyrazolo[1,5-a]pyrimidine, Pyrano[2,3-c]pyrazole und Pyrano[3,4-c]pyrazole Einige neue Pyrazolo[1,5-a]pyrimidine, Pyrano[2,3-c]pyrazole und Pyrano[3,4-c]pyrazole wurden durch Reaktion der α,β-ungesattigten Nitrile 1, 13 und 16 mit 3-Amino-2-pyrazolin-5-on (2), 1-Phenyl-3,5-pyrazolidin-dione (5) und 5-Amino-3-phenylpyrazole (10) synthetisiert.

Journal ArticleDOI
TL;DR: In the 82 patients who benefitted from the shunt, the clinical improvement was dramatic and regression of the ventriculomegaly was inversely proportional to the degree of preoperative ventricular dilatation.
Abstract: One hundred hydrocephalic patients were treated over a 5-year period by shunting the cerebrospinal fluid (CSF) to the internal jugular vein (IJV) against the direction of blood flow. The patients were divided into two groups according to rigidity of their craniums. The pressures recorded during the operations confirmed the results of the experiments in Part II of this investigation. Fifteen patients had their shunting catheters removed or died due to infection (14 patients) or hemorrhage inside a brain tumor (1 patient). The shunts of 12 patients were revised due to technical faults that were corrected in 9 cases. There were no failures or complications related to the dynamics of the shunt. In the 82 patients who benefitted from the shunt, the clinical improvement was dramatic. Regression of the ventriculomegaly was inversely proportional to the degree of preoperative ventricular dilatation. In 5 infants the size of the enlarged head was reduced during surgery. Valveless shunting catheters were used in the first 4 patients, and specially designed valved catheters were used in 96 patients. The follow-up period was up to 5 years.

Journal ArticleDOI
TL;DR: The 5‐(ethoxymethylene)‐4‐thioxothiazolidin‐2‐ones 2a‐c were synthesized and reacted with acrylonitrile, ethyl acrylate under different conditions to yield cycloaddition products 3–14.
Abstract: The 5-(ethoxymethylene)-4-thioxothiazolidin-2-ones 2a-c were synthesized and reacted with acrylonitrile, ethyl acrylate. β-nitrostyrene, N-phenylmaleimide and malononitrile under different conditions, to yield the cycloaddition products 3–14. The antibacterial and antifungal activities of the new products were tested. Reaktionen mit 5-Ethoxymethylenthiazolidin-2,4-dion-Derivaten und ihre biologische Wirksamkeit Die 5-Ethoxymethylen-4-thioxo-2-one 2a-c wurden synthetisiert und mit Acrylnitril, Ethylacrylat, β-Nitrostyrol, N-Phenylmaleinsaureimid und Malonodinitril unter verschiedenen Bedingungen umgesetzt. Die Wirkungen der neuen Verbindungen gegen Bakterien und Pilze wurde gepruft.


Journal ArticleDOI
K.H. Batanouny1
01 Aug 1987-Catena
TL;DR: In this article, a compilation of the available information about the plant ecology and the plant life in the Arab Gulf countries is presented, including Bahrain, Kuwait, Oman, Qatar, Saudi Arabia and United Arab Emirates.
Abstract: The study is a compilation of the available information about the plant ecology and the plant life in the Arab Gulf Countries. These countries include: Bahrain, Kuwait, Oman, Qatar, Saudi Arabia and United Arab Emirates; with an area of 2560074 sq.km. Records obtained by the author during the excursion and botanical studies in these countries are included. The climatological data and the physiography of the area are investigated as regards their influence on the plant life. The plant communities recorded by the different investigators and by the author are given. These communities comprise three main groups, namely, a) desert plant communities, dominated by grasses (5), sedges (1), under-shrubs (17), shrubs and trees (13), b) halophytic plant communities (9), c) mountainous plant communities (5). The rhythmic, irregular, developmental and retrogressive changes in the vegetation are investigated. The direct and indirect effects of the human activities on the desert vegetation are discussed.

Journal ArticleDOI
S.T. Ismail1
TL;DR: This review consolidates several widely scattered reports as projected against the author's own experience on reproduction in the dromedary and is hoped that the information is of particular help for those in charge of the breeding of dromingaries in zoological gardens and animal parks in countries where the one-humped camel is a rare species.

Journal ArticleDOI
TL;DR: On the basis of its sporogonic development in the mosquito, the haemogregarine from Mabuya quinquetaeniata which Wenyon (1909) named Karyolysus gracilis is transferred to the genus Hepatozoon.
Abstract: Developmental stages of Hepatozoon gracilis (Wenyon, 1909) comb. nov. are described from the tissues of Mabuya quinquetaeniata, an Egyptian skink, and from the mosquito Culex pipiens molestus. Schizogony occurred in the parenchyma cells of the skink liver. There were two types of schizonts: one with 25–50, average 40, micromerozoites and the other with 3–16, average 11, macromerozoites. Gametocytes developed in erythrocytes and measured 18–22.5 Μm in length and 0.9–1.4 Μm in width (mean of 21.3×1.14). After syzygy in the haemocoel of the mosquito, the microgamont produces four uniflagellated microgametes (8×3 Μm with a flagellum of about 22.5 Μm); on day 3 post infection (p.i.) one of them fertilizes the macrogamete. Development of the oocysts took place in the mosquito haemocoel leading to formation of an average of 28 sporoblasts/oocyst (range 8–50)on days 10–12 p.i. Beginning at day 16 p.i. (8–24) averaged by 17 sporozoites per sporocyst were observed. Each sporozoite is curved and banana-shaped with round ends measuring 10×32 Μm. On the basis of its sporogonic development in the mosquito, the haemogregarine from Mabuya quinquetaeniata which Wenyon (1909) named Karyolysus gracilis is transferred to the genus Hepatozoon. Experimental transmission was successful by oral administration or by i.p. inoculation of the infectious stages (sporozoites) to uninfected skinks and led to the appearance of blood stages after 5 or 4 weeks, respectively.

Journal ArticleDOI
TL;DR: Statistical analysis showed that Azospirillum strains 5631, Sp Br 14, E15 and SC22 significantly increased the plant dry weight and nitrogen uptake while inoculation with strains M4 and SE had no significant effect in that respect.
Abstract: The response of the cotton plant to inoculation with six strains of Azospirillum brasilense was investigated under subtropical conditions in Egypt. Azospirilla populations and activities were increased as a result of root inoculation with liquid inoculum of Azospirillum sp. Highest C2H2 — reduction activities on roots were obtained with strains S631 and Sp Br 14 (means of 216.85 and 209.50 nmol C2H4g−1 root h−1 respectively) while strain M4 gave the lowest activity (mean of 100.8 nmol C2H4g−1 root h−1). Statistical analysis showed that Azospirillum strains 5631, Sp Br 14, E15 and SC22 significantly increased the plant dry weight and nitrogen uptake while inoculation with strains M4 and SE had no significant effect in that respect.

Journal ArticleDOI
15 Sep 1987-Wear
TL;DR: In this paper, a comparison between the cutting edge durabilities of uncoated and coated tools when oblique turning mild steel at different cutting speeds has been carried out and wear curves have been plotted and Taylor equations have been derived.

Journal ArticleDOI
TL;DR: In this paper, the temperature dependence of structural channges of (NH4)2SO4 has been investigated using X-ray, DTA, and TMA measurements from room temperature down to 5 K.
Abstract: X-ray, DTA, and TMA are used to study the temperature dependence of structural channges of (NH4)2SO4. The measurements are made from room temperature down to 5 K. The lattice parameters and unit cell volume as a function of temperature, the DTA and MTA show a first order transition from the paraelectric phase to the ferroelectric phase at 233 K. The phase transformation is neither of order-disorder type nor ferrielectric type, and involves a symmetry change from the orthorhombic space group Pnam-D in the paraelectric phase to the orthorhombic space group Pna21-C in the ferroelectric phase where all atoms are in general positions. The unit cell contains four formula units consisting of two nonequivalent kinds of ammonium ions, namely, NH(I) and NH(II), and one kind of sulphate ion in both the phases. The tetrahedral molecules of NH and SO are distorted from regular tetrahedra, being accompanied with permanent dipoles. Rontgenbeugung, DTA und TMA werden benutzt, um die Temperaturabhangigkeit von Strukturanderungen in (NH4)2SO4 zu untersuchen. Die Messungen werden zwischen Zimmertemperatur und 5 K durchgefuhrt. Die Gitterparameter und das Volumen der Einheitszelle in Abhangigkeit von der Temperatur, DTA und MTA zeigen einen Ubergang erster Ordnung von der paraelektrischen Phase zur ferroelektrischen Phase bei 223 K. Der Phasenubergang ist weder vom Typ Ordnung-Fehlordnung noch vom ferrielektrischen Typ und schliest eine Symmetrieanderung von der rhombischen Raumgruppe Pnam-D in der paraelektrischen Phase zur rhombischen Raumgruppe Pna21-C in der ferroelektrischen Phase, in der alle Atome sich in allgemeinen Positionen befinden. Die Einheitszelle enthalt vier Formeleinheiten und besteht aus zwei nichtaquivalenten Arten von Ammoniumionen, NH(I) und NH(II) und einer Art von Sulfation in beiden Phasen. Die Tetraedermolekule von NH und sind gegenuber regularen Tetraedern verzerrt und von permannenten Dipolen begleitet.

Journal ArticleDOI
TL;DR: In this paper, the authors describe and summarize the results of new interdisciplinary techniques for recovering and analyzing historical and paleoenvironmental data from mid-Holocene archaeological and geological deposits in the modern Nile floodplain at the site of Hierakonpolis in Upper Egypt.
Abstract: We describe and summarize the results of new interdisciplinary techniques for recovering and analyzing historical and paleoenvironmental data from mid-Holocene archaeological and geological deposits in the modern Nile floodplain at the site of Hierakonpolis in Upper Egypt. Application of these techniques has produced the first stratigraphic link between historic (Early Dynastic) and late prehistoric (Predynastic) periods in the Nile Valley at a site which played a central role in the evolution of Egyptian civilization.

Journal ArticleDOI
TL;DR: In this paper, a 2D numerical model incorporating nonstationary electron dynamics is used to investigate the complex transport phenomena governing the operation of sub-micron gate GaAs MESFET's.
Abstract: A novel 2-D numerical model incorporating nonstationary electron dynamics is used to investigate the complex transport phenomena governing the operation of sub-micron gate GaAs MESFET's. A detailed theoretical analysis of different phenomena observed in subhalf micron devices is given. These include velocity overshoot, stationary and travelling domain formation, soft pinch off, excess drain current etc. The small signal parameters g m , g d and C gs and their dependence on bias condition are evaluated. The effects of physical quantities such as mobility and interface barrier on carrier injection and transport and consequently on device performance are presented.

Journal ArticleDOI
TL;DR: In this paper, four 15-membered ring cyclic compounds with two oxygen and two nitrogen atoms incorporated in the ring were prepared and evaluated as neutral carriers in lithium ion-selective electrodes.
Abstract: Four 15-membered ring cyclic compounds with two oxygen and two nitrogen atoms incorporated in the ring were prepared and evaluated as neutral carriers in lithium ion-selective electrodes. These ionophores, along with potassium tetrakis (p-chlorophenyl)borate and o-nitrophenyloctyl ether (NPOE), were included in the PVC matrix that coated the tip of a silver-wire electrode. The potentiometric selectivities of the electrodes towards lithium over sodium, potassium, calcium and magnesium were determined. Selectivity coefficients, KLi, Napot., as low as 9.5×10−3 were obtained and smaller coefficients for other metals, KLi, Mpot., were found. A calibration curve for lithium in the presence of 140 mmol/l sodium, with a linear portion having a slope of 51 mV/decade, was obtained. The effect of incorporating 1% trioctylphosphine oxide (TOPO) in the electrodes was studied. Comparison with the results obtained with 15-crown-4-ethers is made.

Journal ArticleDOI
M.F. El-Refaie1
TL;DR: In this article, the performance of the basic vertical and horizontal types of external shading devices was studied in detail, and the different performance modes are presented in the form of shading masks featured by the cutoff angles.