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"إنْ" الناسخة ؟! بين مقولات النحويين وواقع استخدامها
No full textترى هذه الدراسة "إنْ" التي يسميها النحويين النافية هي نفسها "إنْ" المخففة من الثقيلة "إنّ" , ووظيفتها توكيد مضمون الجملة بعدها , فالأولى تؤكد النفي والثانية تؤكد الإثبات , وفي توكيد "إنْ" للنفي تحذف أداته لقرينة تركيبية هي في الغالب "إلا" الحاصرة ,وغير ذلك من قرائن النفي التركيبية , وقد تكون قرينة الحذف سياقية كتآلف تركيب "إنْ" مع تراكيب يكون الحدث فيها غير متحقق الوقوع كالنفي والاستفهام وغيرها ,و تربط الدراسة بين "إنْ" و "إنما" في الوظيفة الدلالية حصرًا وتأكيدا, فهما فرعان لأصل واحد "إنّ" . أما ما أورده النحويون من شواهد نصب فيها الاسم بعد "إنْ" فترى الدراسة صلاحية نصبه على أنه حال سدت مسد الخبر, أو أنه خبر لكون محذو
"الحماية الدولية لحقوق الطفل في الظروف الاستثنائية – دراسة في ضوء أحكام العرف الدولي والقانون الدولي الإنساني"
No full textيهدف المؤلف إلى التوعية بحقوق الطفل في أثناء الظروف الاستثنائية في محاولة للسعي إلى تعديل بعض الأطر الموضوعية للحماية على المستوى الدولي ولعل أبرزها نظام روما الأساسي
Analytic Solution for the Magnetohydrodynamic Rotating Flow of Jeffrey Fluid in a Channel
No full textIn this work, the homotopy analysis method is applied to enable discussion of the three-dimensional shrinking flow of Jeffrey fluid in a rotating system. The fluid is electrically conducting in the presence of a uniform applied magnetic field, and the induced magnetic field is neglected. The similarity transformations reduce the nonlinear partial differential equations into ordinary differential equations. The convergence of the obtained solutions is checked. Graphs are plotted and discussed for various parameters of interest
Peristaltic Motion of Power-Law Fluid with Heat and Mass Transfer
No full textThe effects of wall properties and heat and mass transfer on the peristalsis in a power-law fluid are investigated. The solutions for the stream function, temperature, concentration and heat transfer coefficient are obtained. The axial velocity, temperature and mass concentration are studied for different emerging parameter
Influence of wall properties on peristaltic transport of second grade fluid with heat and mass transfer
No full textThis paper discusses the effects of heat and mass transfer on the magnetohydrodynamic (MHD) peristaltic flow of second grade fluid in a channel with flexible walls. Expressions of stream function, temperature, concentration field, and heat transfer coefficient have been computed. The effects of sundry parameters are sketched and examined. The known results of viscous fluid are obtained as the limiting cases of the present expressions
Saudi nursing student’s perception of effective clinical instructors’ characteristics
No full textThe clinical experience has been recognized as a significant and very essential component of nursing education. Clinical instructors have a responsibility not only to their students but also to clients and the nursing profession to identify and exhibit effective clinical teacher characteristics. Moreover, as the clinical experiences and its resources are limited, students must optimize clinical practice opportunities; they must therefore, work with effective clinical instructors.
The purpose of this study is to determine the characteristics of effective clinical instructors as perceived by Saudi nursing students.
The Nursing Clinical Teacher Effective Inventory (NCTEI) developed a 48-item Likert scale checklist describing discrete teachers characteristics clustered into five subscales or categories: teaching ability, nursing competence, personality traits, interpersonal relationships and evaluation.
300 Saudi female nursing students, enrolled in the 4th to 8th term of their study in different colleges of nursing will be asked to participate. This sample also includes students from the college of health sciences, who are enrolled in the second term, of the first year, till those in the second term of the third year
Polypharmacy and patterns in drug prescribing at a primary healthcare centre in the Riyadh region of Saudi Arabia.
No full textOBJECTIVE:
To elucidate the various patterns in drug prescribing in a non-Ministry of Health-affiliated primary healthcare centre model (Riyadh Kharj Military Hospital) in Saudi Arabia.
METHODS:
A retrospective analysis of pharmacy records of the Riyadh Kharj Military Hospital was undertaken. A total of 4781 prescriptions archived over a period of 6 months (January-June 2001) were statistically analysed using Statistical Package for the Social Sciences (SPSS). Number, types, therapeutic duration and distribution of drugs were evaluated. Age distribution and documentation adequacy were also reviewed and monitored. Therapeutic classification of drugs was carried out according to the British National Formulary system.
KEY FINDINGS:
Of the total prescriptions, 47.8% were for male patients and 50.1% for females. Prescriptions for the paediatric population accounted for 19.5% whereas 13.7% of drugs were prescribed to the geriatric cohort. A mean of 2.7±1.6 drugs were prescribed per patient. In multidrug prescriptions, 32.3% contained two drugs and 22.1% prescriptions had four drugs or more. Mono-drug prescriptions accounted for 21.6% of prescriptions. Paracetamol (13.9%) was the most commonly prescribed drug followed by multivitamins and cough syrups with 5.0 and 3.7%, respectively. The most common therapeutic classes of drugs prescribed were analgesics, antipyretics, antihistamines, and vitamins and minerals, making up a third of all prescriptions. Dosage form, dose and routes of administration were not present in 21.7, 8.8 and 99.6%, respectively.
CONCLUSION:
Polypharmacy appears to be a problem in primary health care, which requires stricter pharmacovigilance and constant reviewing. We recommend the establishment of an efficient local prescribing policy through an effective practice-based Pharmacy and Therapeutic Committee, training in prescribing to be introduced in medical schools and the lending of support to continuous education programmes targeting prescribing skills
"علاقة الموقف الدرامي بإيقاع الخطاب و بنيته في الشعر المسرحي ، مسرحية " العباسة " لعزيز أباظة أنموذجًا"
No full textحاول بعض العروضيين والنقاد القدماء والمحدثين إعطاء بحور الشعر العربي صفات بهدف التعرف على ما يمكن أن يُسمى بالذائقة العربية كما تبدت في انطباعات النقاد عن الأوزان. ويرى البعض أن هذه الأحكام لا تعدو أن تكون انطباعًا لحس مُدرَّب وذوق خبير، إنْ صدق على بعض القصائد فقد لا يصدق على بعضها الآخر . و أنها أحكام تتنافى مع الإبداع الشعري النابع من التركيب و اختيار مفردات من مجالات دلالية معينة محكومة بسياق مخصوص يساعد الوزن بوصفه أحد العوامل التي تُبنى القصيدة عليها . وهو بذلك يعادل التنغيم في النثر بوصفه أحد عناصر شكل الخطاب الشفهي بالإضافة إلى المستوى التركيبي والدلالي " فالمرسل لا يركن في خطابه فقط إلى المستوى الصرفي والمعجمي والتركيبي ؛ لتحديد مقاصده ، بل يوظف إلى جانب ذلك اختلاف مستويات التنغيم " كما أنه يعد أحد عناصر قوة المنطوق الإنجازية التي بها يمكن تقويته أو إضعافه تبعًا لسياق الموقف ، وهو ما يسمى بالتشكيل الصوتي أو الوسائل التطريزية. انطلقتْ هذه الآراء بناء على القصيدة الشعرية الغنائية ، التي قد تكون ذات موضوع واحد أو ذات موضوعات متعددة . فكيف يكون الحال بالنسبة للشعر المسرحي ؟
إن الشعر المسرحي يختلف عن الشعر الغنائي ، فالحوار في الشعر المسرحي يقتضي الشاعر كثيرًا من ألوان الانقباض والانبساط ، والانتقال من حال نفسية إلى حال أخرى تمليها أحوال أبطال المسرحية ، وتغير اتجاهاتهم الذهنية . فإلى أي مدى يمكن أن يصدق أحد هذين الرأيين على الشعر المسرحي ؟ وإلى أي مدى يمكن أن تكون علاقة الترابط بين الموقف الدرامي ، أو ما يسمى بسياق الموقف ، والإيقاع الشعري ، وما يشمله من بحور الشعر المستعملة في كل موقف ، وكذلك أنواع القوافي ، وأصوات الروي ؟ وهل يستطيع الإيقاع الشعري أن يقوم بمهمة التعبير عن الحالة النفسية لأبطال الموقف و مقاصدهم وحده، أو أن هناك عوامل أخرى تتلاحم معه لأداء هذه المهمة ؟ وهل يمكن أن يتراجع دور الإيقاع الشعري في بعض المواقف ؛ فيفسح المجال لعوامل التركيب ودلالات الكلمات والصيغ الصرفية لتقوم بهذه المهمة دونه
Leptin level in serum of men donating blood at KKUH in relation to anthropometric measurements
No full textIn recent years leptin hormone has a great importance to its relationship with obesity by regulating eating and energy expended in its impact in some centers in the brain.
The objective of the study assessing the level of the hormone leptin of Saudi men donating blood at king khaled university hospital at the donation centre, and its relationship to anthropometric measurements, the
donors were 212 healthy volunteer from different regions of the Kingdom and they were randomly selected to estimate the level of leptin in the serum of the blood, different weights was estimated that the body mass index BMI was calculated, measuring blood pressure, and the social and economic situation, education, and the question for some of the practices related to nutrition for all volunteers.
The results of analysis of previous data that 35.4% aged <25, while the proportion of the age from 25 -< 40 is 51.4%, and the age of 40 and above by 13.2%. The previous results also showed similar in terms of marital status 50% married and unmarried couples equally, and the proportion of 46.2% estimated monthly income of between from 5000 - <10000, and 50% of them university graduates, and the proportion of those living in the Central Region 56.6%, and the proportion of non- smokers is 61.4%, and the percentage of the sport is practiced consistently 27.8%. The study showed that 40% of the volunteers were overweight, and about 30% are obese, while 27.4% have a normal weight
The study showed high levels of leptin with increasing body weight ,and high level of hormone when married. In conclusion increasing of leptin hormone to healthy individuals is an indicator of weight gain
ERYTHROCYTES AS A POTENTIAL CARRIER FOR WATER SOLUBLE DRUGS: PRAVASTATIN AS A MODEL DRUG
No full textMastersRed blood cells (RBCs) can provide a natural, safe and abundant carrier to prolong the life span in the bloodstream and thus enhance the efficacy of certain therapeutic agents, while restricting their accessibility to the extravascular compartment and thus reducing side effects. Methods for encapsulation of different drugs into RBCs have been proposed, including endocytosis, osmosis based and erythrocyte membrane perturbation. Drug loaded erythrocytes retain biological activity and circulate in a functionally active form in the bloodstream without hemolysis or elimination by reticuloendothelial system. Therefore, erythrocytes allow prolongation of the functional half-life of therapeutic drugs.
Pravastatin is one of the most potent 3-hydroxy-3- methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors that are used in the treatment of hyperlipidaemia. Recent evidence is now emerging indicating that statins may have beneficial actions apart from its hypolipidaemic effect. The statin drugs are now found also useful in the treatment of several diseases such as osteoporosis, Alzheimer, cardiac diseases, organ transplantation, stroke and diabetes. Pravastatin has low bioavailability (17%) due to many reasons. The major one is the high destruction by gastric secretions, also, due to incomplete absorption via efflux effect of both CYP450 and phosphrylated glycoprotein (Pgp). The aim of this study is to enhance drug bioavailability, decreasing its dose and develop a sustained release delivery system of pravastatin by using erythrocytes as drug carriers. In the current study pravastatin was loaded by two methods at different loading conditions to obtain optimum loading parameters. In addition to this, a new analytical method for pravastatin bioassay was developed to quantitate pravastatin sodium in the loaded erythrocytes. Chapter 1: Literature review: Application and Safety of Erythrocytes as Novel Therapeutic Delivery Systems Carrier erythrocytes are one of biological drug delivery systems investigated in recent years. The erythrocytes are biocompatible, biodegradable as well as they have long half-life. The drugs with high toxicity, such as cardiotoxic and neurotoxic are selected to encapsulate in the erythrocytes because of their potential for delivery for the liver, spleen and lung. Physical methods like endocytosis and osmotic based methods are used for drug loading into erythrocytes, as well chemical methods are used for the same purpose. After loading of therapeutic agent on erythrocytes, the carrier cells are exposed to physical, cellular as well as biological characterizations. The resealed erythrocytes were used either for sustained release or targeted release of therapeutic agents.
The targeted resealed erythrocytes are structurally modified either by glutaraldehyde, oxidizing agents or by drug itself. The modified carrier erythrocytes have
tendency to be phagocytosed and this accelerates their removal from the circulation and facilitates in their targeting to the organs of reticuloendothelial system. Chapter 2: Ultra performance liquid chromatography as a new validated method for determination of pravastatin sodium in erythrocytes In this part of work, a new method for pravastatin sodium bioanalysis in erythrocytes was developed using ultra performance liquid chromatography (UPLC). UPLC is a relatively new trend giving possibilities in liquid chromatography for, reducing analysis time, solvent consumption and maintaining good efficiency. Also, liquid/liquid extraction method of the drug from erythrocytes was assessed and validated. Pravastatin sodium was extracted from erythrocytes by addition of equal amounts of distilled water with vigorous shaking for blood hemolysis. After erythrocytes hemolysis, double amount of methanol was added, mixed and vortexed for complete protein precipitation. The final mix was centrifuged at 13000 rpm for 15 minutes, and then the supernatant was aspirated and diluted to known volume to be ready for analysis. The extraction method was validated, and average recovery was found between 108.18 and 96.09% which is acceptable according to FDA guidelines. Pravastatin sodium extracted from pravastatin loaded erythrocytes was assayed according to the new developed method. The method was performed on AcquityR UPLC system, AcquityR UPLC BEH C18 column (2.1 mm x 50 mm, 1.7 ƒÊm). The mobile phase was a mixture of 0.25% formic acid in distilled water and acetonitrile (65:35, v/v), with flow rate of 0.5 ml/min and injection volume was 1 ƒÊl. Photodiode Array (PDA) detector was set to acquire 3D data from 210 to 280 nm while the 2D channel was recording at 237 nm, the Column temperature was kept at 50oC while sample temperature was kept ambient. This method was validated and found to be linear with R2 (0.9987 }0.0001), LLOD (0.1 ƒÊg/ml) and LLOQ (0.5 ƒÊg/ml).
Inter and intraday accuracy and precision at LLOQ and range containing low, medium and high concentrations of pravastatin sodium in loaded erythrocytes were also within acceptable limits. Intraday and inter-day accuracy range was (97.93%-102.61%)
and (96.91%-104.75%), respectively. Precision (RSD) within days were less than 6.43 and 0.31, and found to be less than 0.29 and 7.11 between three days. The major advantage of this method is the short retention time (0.6 minutes) that allows running of large number of sample in shorter time. Chapter 3: Loading of pravastatin sodium in human erythrocytes using endocytosis method In this chapter endocytosis was used to load pravastatin sodium in erythrocytes. In endocytosis, the cell engulfs some of its extracellular fluid (ECF) including material dissolved or suspended. A portion of the plasma membrane is invaginated and pinched off forming a membrane-bounded vesicle called an endosome. Erythrocytes were separated from the whole blood by centrifugation at 5000 rpm for 5 minutes, and then the packed erythrocytes were washed and suspended in phosphate buffer saline (PBS) to final hematocrite 45%. The erythrocytes f suspension was incubated with equal volume of PBS containing the drug and incubated for different times to study the effect of time, concentration and temperature. The drug concentrations selected were 2, 4, 8 and 10 mg/ml. The incubation times were 15, 30, 60 and 120 minutes at temperatures 25oC and 37oC. Erythrocytes subjected to loading procedure were separated by centrifugation for 5 minutes at 5000 rpm. The loaded erythrocytes were washed three times, and then the drug was extracted by liquid/liquid extraction and evaluated using UPLC as described in analysis chapter.( chapter 2). Pravastatin was loaded successfully into human erythrocytes with cell recovery 87-93%, and no significant difference in morphology, hematology and osmotic fragility behavior of the loaded erythrocytes.
An elevated loading of pravastatin into erythrocytes was associated with a higher concentration of pravastatin in the incubation medium, in the 2-10 mg/ml concentration range. The highest level of loaded pravastatin by endocytosis was attained using 10 mg/ml of pravastatin with a 2 h incubation time at temperature 37oC. The highest loaded
amount at 25oC was 0.32 mg/100 ƒÊl with loading efficiency 34%, while at 37oC, the highest loaded amount was 0.69 mg/100 ƒÊl with loading efficiency 94%. Chapter 4: Loading of pravastatin sodium in human erythrocytes using hypotonic dilution method. In this chapter pravastatin loading by hypotonic dilution method is described. Hypotonic dilution technique depending on the fact that erythrocytes volume increases by 40-50%, giving rise to holes on cell membrane ranging from 10 nm up to 500 nm by incubation in hypotonic solution. Water and its contents (dissolved drug) flow into the cell through the holes. Afterward, the erythrocytes were removed to an isotonic solution and gain its normal volume, shape and characters with entrapping dissolved drug. Washed erythrocytes are adjusted by PBS to form RBCs suspension with hematocrite 45%. One volume of erythrocytes suspension is added to nine volumes of hypotonic PBS containing known concentration of the drug and incubated for different times at 4oC. PBS was used in 3 different tonicities 0.7, 0.6 and 0.6%. After incubation period, erythrocytes were separated by centrifugation at 3000 rpm for 5 minutes and the supernatant were removed. The packed erythrocytes are resealed in resealing buffer containing 2.5 mmol of (ATP), 2.5 mmol (MgCl2) and 2.5 mmol of (CaCl2). This was done by gently mixing to avoid blood hemolysis and then, incubated for 60 minutes at 37oC. The erythrocytes f suspension was centrifuged for 5 min at 5000 rpm and then, the supernatant was discarded and they were washed for 2 times in cold BPS with centrifugation for 5 min at 5000 rpm. In this study the effect of drug concentration and incubation time were studied, in addition to study the effect of degree of hypotonicity by using hypotonic buffers with different salt (NaCl) concentrations (0.7, 0.6 and 0.5%) for loading.
The results revealed that, human erythrocytes have been successfully loaded with pravastatin using hypotonic dilution method at salt concentration 0.5%, 0.6% and 0.7%, with acceptable loading parameters and moderate morphological changes. However, loading at salt concentration 0.7% exhibit morphological and hematological parameters as same as normal, but 0.6% was selected as optimum condition for drug loading due to
combination of both, higher loaded amount with negligible effects on fragility and hematological parameters of erythrocytes. Chapter 5: From the previous experiments, it was concluded that the pravastatin sodium can be loaded successfully and efficiently into erythrocytes either by endocytosis or hypotonic dilution method with different loading efficiencies and different effects on morphological, hematological and fragility characters. In this part of work, pravastatin was loaded in erythrocytes and the release of pravastatin was studied to determine the possibility of using carrier erythrocytes as extended release system for pravastatin, and also to measure the release kinetics of the pravastatin from loaded erythrocytes in PBS and plasma as well as loaded erythrocytes treated with glutaraldehyde as across linking agent in PBS. Pravastatin was loaded by endocytosis and hypotonic dilution method to compare between them. Pravastatin release in PBS is rapid process compared to release in plasma and after glutaraldehyde treatment, it reaches 76% in PBS after 20 hours and 83% after 23 hours and decreased to 65% after treat with glutaraldehyde after 20 hours and 72% after 23 hours while in plasma it reaches only 66% after 20 hours and 72% after 23 hours. Erythrocytes loading by hypotonic dilution method produce 66% release in PBS and 57% after glutaraldhyde treatment after 20 hours. The releasing pattern of the drug from loaded erythrocytes obeyed first order kinetics. These results suggested that erythrocyte is suitable carrier for retarded released pravastatin. However, the relative impacts of different in vitro findings on the overall in vivo drug delivery efficacy of these cellular carriers remain to be evaluated during the future in vivo studies