I would like to query an XDocument object for a given path, (e.g. "/path/to/element/I/want") but I don't know how to proceed. Something similar to this might work: You can use methods from System.Xml.XPath.Extensions to do this. For example, if you want to select a single element, you would use XPathSelectElement() : The queries don't have to be simple paths like what you described, they use the XPath language.
Even though this is a somewhat older post, it should be noted that LINQ-to-XML can be used as an alternative to System.XML.XPath to find elements based on a path within an XDocument. Note: The LINQ to XML command may need to be altered to accommodate for the actual structure and/or cardinality of the XML. Presented By Qirtas Tauheed (100-E-14) Ointments 2. Definition: “Ointments are semi-solid preparations for application to the skin.” 3. Types of Ointments Medicated ointments Non-medicated ointments 4. Medicated ointments These contain the medicament either dissolved or dispersed in the vehicle as fine powders or in the form of micronized powder e.g. Non medicated ointments These are used as vehicles for preparation of medicated ointments or can be used for their physical effects e.g. Properties of ideal ointments Non sensitizing Non irritating Pharmaceutically elegant Efficient release of medicament at the site of application Water -washable 7.
Ointment Bases Ointment bases are generally classified by the USP into four groups I. Absorption bases III.Water removable bases IV.Water soluble bases 8. 1)Oleaginous bases Oleaginous bases are also termed as hydrocarbon bases. On application to the skin emollient effect occlusive dressings protect against the escape of moisture 9. Examples of Oleaginous Bases a)Petrolatum (USP) is a purified mixture of semisolid hydrocarbons obtained from petroleum. b) White Petrolatum(USP) is a purified mixture of semisolid hydrocarbons from petroleum that has been wholly or nearly decolorized. c)Yellow ointment (USP) is mixture (1000g) of yellow wax (50g) and petrolatum (950g). d)White ointment (USP) This ointment differs from yellow ointment by substituting white wax and white petrolatum in the formula. 2) Absorption bases Absorption bases are of two types: Those that permit the incorporation of aqueous solutions resulting in the formation of water-in-oil emulsions (e.g., hydrophilic petrolatum) Those that are water-in-oil emulsions and permit the incorporation of additional quantities of aqueous solutions (e.g., Lanolin) 12. Examples of Absorption bases a) Hydrophilic petrolatum Hydrophilic petrolatum, USP has the following formula for the preparation of 1000 g: Cholesterol 30 g Stearyl alcohol 30 g White wax 80 g White petrolatum 860 g b) Lanolin obtained from the wool of sheep; is a purified, wax-like substance that has been cleaned, deodorized, and decolorized. 3) Water-removable bases Water-removable bases are oil-in-water emulsions resembling creams in appearance. Because the external phase of the emulsion is aqueous, they are easily washed from skin and are often called ‘water washable’ bases. They may be diluted with water or aqueous solutions e.g. 4) Water-soluble bases Water-soluble bases do not contain oleaginous components. They are completely water-washable and often referred to as ‘greaseless’. Because they soften greatly with the addition of water, large amounts of aqueous solutions are not effectively incorporated into these bases. They mostly are used for the incorporation of solid substances. Selection of appropriate Base • Release rate • Topical or percutaneous drug absorption • Occlusion • Stability of drug • Effect of drug on ointment base • Easily removable • Characteristics of surface for application 16. Preparation of ointments Ointments are prepared by two general methods: - Incorporation - Fusion Incorporation By the incorporation method, the components are mixed until a uniform preparation is attained. Incorporation of solids: The ointment base is placed on one side of the working surface and the powdered components, previously reduced to fine powders and thoroughly blended in a mortar, on the other side. Incorporation of solids The drug (the pink powder) is usually the smaller quantity of the two ingredients. Add an amount of the ointment that is approximately equal in size to the drug. Continue adding until all of the ointment is used. Incorporation of Liquids • Liquid substances are added to an ointment after consideration of an ointment bases capacity to accept the volume required. • Small amount of an aqueous solution may be incorporated into an oleaginous ointment • Hydrophilic ointment bases readily accept aqueous solution. Addition of aqueous preparation to a hydrophobic base • First the aqueous solution incorporated into a small amount of a hydrophilic base.
• Second that mixture then added to the hydrophobic abase. Fusion Method Fusion is the act or procedure of liquefying or melting by the application of heat.
By the fusion method, all or some of the components of an ointment are combined by melted together and cooled with constant stirring until congealed. Heat labile substances added last, when the temperature of the mixture is low enough not to cause decomposition of the ingredients. Fusion Method: In a small scale, the fusion process conducted in a porcelain dish or glass beaker. In large scale, it is carried out in large steam-jacketed kettles. After congealing the ointment may be passed through an ointment mill (in large scale), in small scale rubbed with spatula or in a mortar to ensure uniform texture.