Chapter 057 Photosensitivity and Other Reactions to Light (Part 6) ppsx

... photosensitivity is known as chronic actinic dermatitis. These patients are typically elderly men with a long history of Chapter 057. Photosensitivity and Other Reactions to Light (Part 6) ... energy, become photoexcited, generate ROS, and evoke cutaneous photosensitivity. The mechanism of porphyrin photosensitization is known to be photodynamic, or oxygen-depen...

Ngày tải lên: 07/07/2014, 01:20

... penetrates to the dermis and is capable of altering structural and matrix proteins that contribute to photoaging of chronically sun- exposed skin, particularly in individuals of light complexion. ... between 290 and Photosensitivity occurs when a photon-absorbing chemical (chromophore) present in the skin absorbs incident energy, becomes excited, and transfers the absorbed...

Ngày tải lên: 07/07/2014, 01:20

... extent in the Chapter 057. Photosensitivity and Other Reactions to Light (Part 2) Molecular Targets for UVR-Induced Skin Effects Epidermal DNA, predominantly in keratinocytes and in Langerhans ... released into the circulation from the bone marrow and the liver and are transported to the skin, where they absorb incident energy both in the Soret band, around 400...

Ngày tải lên: 07/07/2014, 01:20

... Chapter 057. Photosensitivity and Other Reactions to Light (Part 5) Polymorphous Light Eruption After sunburn, the most common type of photosensitivity disease is polymorphous light eruption ... exposure. Phototoxicity and Photoallergy These photosensitivity disorders are related to the topical or systemic administration of drugs and other chemicals....

Ngày tải lên: 07/07/2014, 01:20

... Fig. 57-1. Figure 57-1 Chapter 057. Photosensitivity and Other Reactions to Light (Part 7) Porphyria cutanea tarda is the most common type of human porphyria and is associated with decreased ... include an acute photosensitivity characterized by subjective burning and stinging of exposed skin that often An algorithm for the diagnosis of a patient with photo...

Ngày tải lên: 07/07/2014, 01:20

... dioxide 25 Chapter 057. Photosensitivity and Other Reactions to Light (Part 8) Natural photoprotection is provided by structural proteins in the epidermis, particularly keratins and melanin. ... effects of long-term UV-B phototherapy and PUVA photochemotherapy mimic those seen in individuals with chronic sun exposure and include skin dryness, actinic keratoses,...

Ngày tải lên: 07/07/2014, 01:20

... including the face, the neck, and the hands. Major risk factors include male sex, childhood sun exposures, older age, fair skin, and residence at latitudes closer to the equator. Whites of darker complexions ... but this is likely due to failure to control for confounding factors such as sunscreen stability and frequency of application. Since no prospective studies are availab...

Ngày tải lên: 07/07/2014, 01:20

... ability to discriminate disease is described by four indices: sensitivity, specificity, positive predictive value, and negative Chapter 078. Prevention and Early Detection of Cancer (Part 6) ... early in asymptomatic individuals, with the goal of decreasing morbidity and mortality. While screening can potentially save lives and has been shown to do so in cervical, co...

Ngày tải lên: 07/07/2014, 01:20

... as ideomotor apraxia. Commands to perform a specific motor act ("cough," "blow out a match") or to pantomime the use of a common tool (a comb, hammer, straw, or toothbrush) ... network from pyramidal motor systems: commands to execute complex movements are understood but cannot be conveyed to the appropriate motor areas, even though the relevant motor mechanis...

Ngày tải lên: 06/07/2014, 13:20

... objects x and y if and only if either x bears Rtoy, or x bears Rto some z 1 that itself bears R to y, or x bears R to some z 2 that bears R to a z 1 that bears R to y, or . . . Thus, ‘ancestor’ is ... first millennium bc to the middle of the first millennium ad—from Thales and the earliest Pre- Socratics to late Neoplatonists and Aristotelian commen- tators, such as Simplic...

Ngày tải lên: 02/07/2014, 09:20