Showing papers by "Cairo University published in 1972"

Carcinoma of the bilharzial urinary bladder.A study of the associated mucosal lesions in 86 cases

Abstract: The mucosal lesions in the lower urinary tract were examined in 86 cystectomy specimens of bilharzial bladder cancer. Squamous cell carcinoma occurred in 66 cases, transitional cell carcinoma in 18 cases, and adenocarcinoma in two cases. Multiple infiltrative carcinomas were found in 19 cases (22.1%), and these were commonly of the transitional cell type (63.9%). Squamous metaplasia was found in 65.1%, columnar metaplasia in 52.3%, and carcinoma in situ in 40.7%. The ureters, trigone, and urethra were rarely affected by these lesions. Carcinoma in situ was more commonly associated with multiple carcinomas (68.4%) than with single tumors (32.8%). Squamous metaplasia was found in 81.8% of squamous cell carcinomas and in 16.7% of transitional cell carcinomas. The two cases of adenocarcinoma were associated with columnar metaplasia in the adjacent mucosa. Squamous cell carcinoma and adenocarcinoma probably arise from metaplastic epithelium. Total or subtotal cystectomy is recommended because of the high incidence of carcinoma in situ (40.7%) and multiple carcinomas (22.1%).

The fasciomuscular tube of the spermatic cord. A study of its surgical anatomy and relation to varicocele. A new concept for the pathogenesis of varicocele.

Abstract: SUMMARY The anatomical, histological and morphological structure of the fasciomuscular tube which surrounds the spermatic cord was studied in 20 cadavers of full mature neonatal foetal death and in 10 varicocele patients. The spermatic and cremasteric fasciae are composed of elastic fibres impregnated with collagen, and act as an elastic stocking to the cord. Together with the cremasteric muscle they form a fasciomuscular pump which may play an important role in the haemodynamics of the venous return from the cord. Tubal atrophy and subluxation were found in varicocele. Tubal subluxation resulting in inefficiency of fasciomuscular pumping mechanism is discussed as an aetiological factor in varicocele.

Simulating the Small-Sample Properties of Econometric Estimators

Abstract: This note examines the use of indirect Monte Carlo methods in investigating the finite-sample properties of econometric estimators. It is found that the two-antithetic-variate method is far better than straight-forward simulation in estimating the biases of the estimators, but that a method combining the control-variate and the two-antithetic-variate techniques is better for estimating the dispersions. Comparisons with Nagar's approximations to the biases and dispersions are presented.

Eco-physiological studies on desert plants

Abstract: 1. Leptadenia pyrotechnica (Forsk.) Decne. grows in valleys of the Eastern Desert in Egypt where the climatic and edaphic drought is very severe. 2. The transpiration rate is low in winter months and rises by the onset of summer. The rise in transpiration rate is not comparable with that of the evaporation. 3. The maximum transpiration rate is generally attained earlier than the maximum of the evaporating factors, specially in summer. The transpiration curves show a rapid decrease after this maximum despite the continuous rise of the evaporating power of the atmosphere. This points to an effective stomatal regulation. 4. The osmotic pressure ofLeptadenia is relatively low. The osmotic pressure values show narrow daily and seasonal fluctuations. 5. Leptadenia pyrotechnica is one of the most drought resistant plants. Its xeromorphic leafless habit implies reduction in the transpiring surface, while its deep extensive roots and low transpiration rate ensure a favourable water balance. The mechanisms of drought resistance in this plant were discussed.

The development of the chondrocranium of the lacertid lizard, Acanthodactylus boskiana.

Abstract: The trabeculae cranii are at first quite separate from each other, after few days their anterior two fifths are connected by a trabecular plate which is obliterated throughout development. The paired origin of the parachordal plate is not observed. The fused posterior orbital cartilages chondrify in the form of a wide short plate, traversed by the oculomotor and trochlear nerves. The basicranial fenestra and fenestra ovalis are formed by the degeneration of pre-existing cartilage. The cochlear portion is completely fused with the parachordal plate from the very beginning. The elements of the pterygoquadrate are fused together. The quadrate and Meckel's cartilage are in close contact from the very beginning. While the lower part of the interorbital septum is derived from the trabecula communis, its upper part is derived from the anterior orbital cartilages. The lateral parts of the fused posterior orbital cartilages give rise to most of the taeniae and pilae of the orbitotemporal region. There is only one commissure between the auditory capsule and parachordal plate. A cartilaginous connection between the distal portion of the columella auris and ceratohyal persists for some time. The parietotectal and paranasal cartilages are fused together from the very beginning. The processus paroticus originates from the columella auris. In the fully formed stage the notochord is completely embedded in the occipital condyle. The union between the condyle and odontoid process persists. The auditory capsules and occipital arches contribute to the formation of the tectum synoticum plus posterius. The prefacial commissure and facial foramen lie in front of the cochlear portion. The columella auris possesses a processus internus (connected with the quadrate), but the processes a dorsalis has completely disappeared. The orbitotemporal region is quite complete. A medial fenestra is formed in the planum supraseptale. A fenestra is observed in each of the interorbital and nasal septa. The lamina transversalis anterior is fused with the parietotectal cartilage. A complete zona annularis is present. The outer wall of the paranasal cartilage is perforated by a large fenestra lateralis. The parietotectal and paranasal cartilages and the posterior process of the lamina transversalis anterior contribute to the formation of the concha nasalis. There is a contact between the planum antorbitale and nasal septum. The pterygoid process has disappeared. The common characters of the lacertid chondrocranuium are deduced.

Plication operation: a new technique for the radical cure of varicocele.

Abstract: SUMMARY A new technique for varicocele treatment is described. It consists of plication of the fascio-muscular tube of the spermatic cord, aiming at correction of the tubal subluxation commonly found in varicocele. Fifty-two patients were operated on with encouraging results. The factors to which the results may be attributed are discussed. In contrast to the other commonly practised procedures, the plication operation is an attempt at correction of a basic factor responsible for varicocele initiation.

The Bias of the Two-Stage Least Squares Estimator

Abstract: This article derives the bias of the two-stage least squares estimator to the order of T-2, T being the number of observations. It is found that when the degree of overidentification in the equation concerned is unity, the 2SLS bias is zero to this order of approximation.

Our present knowledge on the flora and vegetation of libya bibliography

Abstract: SUMMARY A short account on the geography and climate of Libya is given. The estimated number of epithets in the Libyan flora is 1,600 species and 600 infraspecific epithets. The history of botanical exploration in Libya is chronologically dealt with. Important collections and their contributors from 1703 till the present time are mentioned. A comprehensive bibliography on the natural history of Libya is given. It includes 791 references covering studies dealing with flora and vegetation and such related topics as forestry, horticulture, climatology, geography and travels. Literature on cryptogams is excluded. The accumulation of this bibliography will be a step towards preparing a flora of Libya.

Reactions with 4,5-Disubstituted 2-Mercaptoimidazoles and their derivatives

Abstract: 4,5-Disubstituted 2-mercaptoimidazoles react with chloroacetic acid to form S-carboxy-methyl derivatives, which readily cyclise to the corresponding 2,3-dihydro-imidazo[2,1-b]-thiazol-3-ones. Substituted amides of 2-imidazolylthioacetic acids have now been obtained by the action of amines on the latter compounds. The 2-arylidene and 2-arylazo derivatives of 2,3-dihydroimidazo[2,1-b]thiazol-3-ones are prepared. The action of GRIGNARD reagents on the 2-arylidene derivatives results in addition to the exocylic double bond.

Reactions with 5‐Substituted Isorhodanines. I

Abstract: Treatment of 5-arylideneisorhodanines 1 with GRIGNARD reagents, effects addition of the reagent to the double bound of the lateral chain to yield products, proved to have structure 2. The thiono group in 1 and 2 condenses with aniline to yield the corresponding 5-substituted-4-phenylimino-2-thiazolidinones 3 and 4. Alkylation of 1 and 2 with alkyl halides or with ethereal diazomethane results in the formation of the S-alkyl derivatives 5 and 6, respectively.

The aetiology of impetigo contagiosa.

Abstract: Summary.— The study egtailed bacteriological investigation of 131 cases of impetigo contagiosa, including the isolation and identification of the offending organisms. The data showed the presence of Staphylococcus aureus in pure culture in 40.5% of the cases, and in mixed growth with betahaemolytic streptococci and other organisms in 47% of the cases. Streptococci came next in frequency and were isolated in pure culture from 9.1% of cases, and in combination with other organisms in 36.7% of the cases. A haemolytic diphtheroid having the characteristics of Corynebacterium pyogenes was isolated in pure culture from one case and in mixed growth in 5.3% of the cases.

Lactation patterns in Egyptian women. II. Chemical composition of milk during the first year of lactation.

Abstract: The composition of human milk during the first year of lactation was studied. The effect of age, parity and the length of inter-delivery interval on the composition is described. Of the three parameters, the length of inter-delivery intervals was the most important, while the other two were weakly correlated. (Summary in Arabic, p. 409.)

Spectroscopic Studies on Some Benzenethiols

Abstract: The electronic absorption spectra of some derivatives of benzenethiol were studied in the visible ultraviolet regions in a number of solvents. Solvent effects on the position of band maxima helped in identifying the different types of transitions obtained, namely n → π*, π → π*, and intramolecular charge transfer transitions. Energies of the charge transfer bands were computed theoretically and agreed well with the experimental results. Transition probability coefficients and oscillator strength were calculated for the different transitions. Numerical values of the oscillator strength helped to differentiate between the various types of transitions.

Systemic action of benomyl against late-wilt disease of maize.

Abstract: SUMMARY Benomyl (methyl-I-(butyl carbamoyl)-2-benzimidazole carbamate) at 2.5 to 100 ppm completely inhibited the growth in vitro of Cephalosporium maydis Samra, Sabet & Hingorani, the causal fungus of late-wilt of maize. In pot experiments, late-wilt was controlled by applications equivalent to 10 ppm benomyl/unit wt dry soil at sowing but not by applications 30 days after sowing or by seed treatments (dusts and dips). A fungitoxic substance was detected in benomyl-treated soil, planted with maize, 120–150 days after treatment and for 150–180 days in unplanted soil. Sap expressed from maize grown in benomyl-treated soil was also fungitoxic, especially that from the roots and distal parts of the leaf blades. In the field, soil applications of benomyl to 10 kg/feddan (4200 m2) failed to control late-wilt. Tests indicated little fungitoxicity in the sap of maize plants 25 days after sowing.

Reactions of Arylhydrazones of Some α‐Cyanoketones with GRIGNARD Reagents

Abstract: The arylhydrazones of ethyl α-oxo-cyanoacetate 1a–e and the α-arylhydrazones of β-phenyl-α,β-diketopropionitrile 2a–e, react with GRIGNARD reagents at room temperature to yield the cyanocarbinols 3a–h. On the other hand, 1 and 2 react with phenylmagnesium bromide in refluxing ether-benzene mixture, to yield the imino derivatives 4a–d. 3a–e are dehydrated by hot acetic acid to yield compounds 5a–d. Similar treatment of 41–d affords the α-arylazo-β-phenylchalcones 6a–d which react with hydroxylamine to yield isoxazoline derivatives 7a–d. Treatment of 1b, d with ethereal diazomethane results in the formation of the N-methylarylhydrazones 8a, b. The arylhydrazono-malodinitriles 9 react with GRIGNARD reagents to yield the imino derivatives 10.

Factors in the Determination of Preference Judgments for Polygonal Figures: A Comparative Study

Abstract: On demande a de larges echantillons egyptiens d'etudiants en Arts et d'etudiants d'autres disciplines de juger une serie de polygones d'apres leurs preferences esthetiques et a l'aide d'une echelle en 7 points. Les jugements sont soumis a une intercorrelation separee pour 3 groupes (etudiants en Arts du sexe masculin, etudiants en Arts du sexe feminin et etudiants d'autres disciplines du sexe feminin) et on procede a une analyse factorielle des matrices obtenues. Quinze facteurs sont extraits et soumis a une rotation Varimax. Les facteurs retenus sont compares a des facteurs similaires obtenus precedemment chez des sujets anglais. Il est possible d'interpreter une douzaine de facteurs pour l'echantillon egyptien et ceux-ci s'averent tres semblables aux facteurs observes chez les Anglais. Les A. concluent que les resultats ne sont pas en faveur d'une interpretation purement culturelle des determinants des jugements esthetiques preferentiels.

Iron metabolism in Egyptian infants with protein-calorie deficiency.

Abstract: I . Studies were made of iron absorption in eighty-five infants who were suffering from protein-calorie deficiency (kwashiorkor and marasmus) and in eight infants who were suffering from Fe-deficiency anaemia : twenty-one healthy infants were used as control subjects. Factors affecting absorption concentration of serum total protein and its fractions; serum Fe; transferrin (as indicated by total Fe-binding capacity) and its percentage saturation; blood haemoglobin; total blood Fe; and the state of Fe stores in the liver were also investigated. Four of the infants who were suffering from severe kwashiorkor were selected for a follow-up study and were given a high-protein diet and blood transfusions. 2. Alimentary Fe absorption was retarded in infants with protein-calorie deficiency. Total serum proteins and its fractions were reduced. Blood haemoglobin, total blood Fe, serum Fe and total Fc-binding capacity were also decreased but the percentage of transferring saturation was increased. Liver proteins per g wet weight of liver were decreased, whereas liver non-haem Fe was increased. The extent of these changes varied according to the clinical condition. 3. In infants with Fe-deficiency anaemia there was no change in liver protein concentrations or total serum proteins, except for a slight increase in the P-globulin fraction of the latter. Blood haemoglobin and total Fe were reduced, whereas serum total Fe-binding capacity was raised and the percentage of transferrin saturation was lowered. A fall in the liver non-hacm Fe concentration was observed. 4. After giving a high-protein diet to infants with severe kwashiorkor, the characteristic anaemia associated with protein-calorie deficiency changed and the general manifestations of Fe-deficiency anaemia emerged. After blood transfusion, these infants showed a marked clinical improvement.

Investigations on the effect of drift-field-dependent mobility on MOST characteristics—Part II: Q B field dependent

Abstract: The MOST V-I static characteristics were investigated in Part I [1], taking the mobility µ only as variable with the drift field. In this part, the analysis is extended to include the simultaneous variations of the mobility µ and the bulk charge Q B along the channel. From the mobility point of view, the analysis follows that of Part I with the two approaches of piecewise and continuous mobility variations. However, in this case the resulting equations are only solvable numerically, and the computed results are plotted. The results show that effects due to the additional variation in Q B along the channel are in the same sense and enhance those due to variation in mobility alone. Also, higher doping and greater oxide thickness show themselves in a way as though the mobility were approaching the limit of velocity saturation. The overall effects show more reduction in current levels as well as output and mutual conductances, and increased tendency of earlier saturation. As far as these effects are concerned, the results favor a MOST of small oxide thickness and long channel. However, since a long channel impairs the gain and high-frequency characteristics, the results given in this paper help to show how a compromise may be obtained.

Anodic polarization of tungsten in neutral and alkaline solutions under conditions of anode film growth

Abstract: Anodic polarization of W has been studied in neutral (Na2SO4, NaCl) and alkaline solutions (ammonium borate, Na2CO3, Na3PO4, and NaOH) by the galvanostatic method under conditions which lead to anode film growth. The rate of oxide growth has been calculated as a function of current density, nature and concentration of electrolyte. Film growth to potentials above 100 V is achieved in alkaline solutions, provided the solution is dilute and the current density is high. The applicability of the high field ionic conduction has been verified from the dependence of both reciprocal capacity and potential on the logarithm of current density. Data are recorded for the coulometric increase of oxide thickness. The constants of the exponential law, and the electric field. Anodische Polarisation von Wolfram in neutralen und alkalischen Losungen bei anodischem Filmwachstum Die anodische Polarisation von Wolfram wurde in neutralen (Na2SO4, 1 NaCl) und alkalischen Losungen (Ammoniumborat, Na2CO3, Na3PO4, NaOH) galvanostatisch und unter Bedingungen untersucht, welche Deckschichtbildung an der Anode ermoglichen. Die Geschwindigkeit der Oxidschichtbildung wurde in Abhangigkeit von der Stromdichte sowie der Art und der Konzentration des Elektrolyten berechnet. In alkalischen Losungen findet Deckschichtbildung bei Potentialen oberhalb 100 V statt, sofern mit verdunnten Losungen und hoher Stromdichte gearbeitet wird. Aufgrund der Tatsache, das die reziproke Kapazitat und das Potential vom Logarithmus der Stromdichte abhangig sind, wird nachgewiesen, das fur diesen Fall die Ionenleitung im starken elektrischen Feld Gultigkeit hat. Abschliesend werden Angaben zur Zunahme der Oxidschichtdicke mit dem Stromdurchgang, zu den Konstanten des Exponentialgesetzes und dem elektrischen Feld gemacht und der Zusammenbruch der Oxidschicht beschrieben.