Author: Albert

Hereditary hemorrhagic telangiectasia, also referred to as Osler-Weber-Rendu syndrome, is a rare autosomal dominant disorder that is characterized by multiple telangiectatic lesions involving the skin, mucous membranes, and viscera. One form of the disorder, characterized by a high frequency of symptomatic pulmonary arteriovenous malformations and cerebral abscesses, has been identified. Both ENG and ALK-1 encode putative receptors for transforming growth factor-beta (TGF-β) superfamily that play a critical role for proper development of the blood vessels.17 lary venules with connections to dilated arterioles, initially through capillaries and later directly. Perivascular mononuclear cell infiltrates also are observed. The vessels of HHT show…

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Hereditary hemorrhagic telangiectasia (HHT). HHT is a condition in which occult blood loss in the gut may lead to severe iron deficiency anemia. The diagnosis usually is clear from a careful clinical examination, although the telangiectasia are not always as obvious, as in this patient with multiple lesions on the face, lip, and tongue. The patient had received multiple blood transfusions over many years because of HHT-associated gastrointestinal blood loss, and he had developed cirrhosis associated with hepatitis B antigen positivity, probably as a result of transmission of hepatitis B in transfused blood. (From Forbes CD, Jackson WF: Color atlas…

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Hemarthrosis and soft tissue hematomas are seldom found in these patients.4, 8, 11 Patients with hemophilia usually do not bleed abnormally from small cuts such as razor nicks. After larger injuries, however, bleeding out of proportion to the extent of injury is common. This bleeding may be massive and life threatening or it may persist as a slow, continuous oozing for days, weeks, or months. The onset of excessive bleeding usually is delayed. At the time of surgery or injury, hemostasis appears to be normal. Bleeding of sudden onset and serious proportions may develop several hours or even several days…

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Loosely speaking, if the graph of a function fx has no jumps then fx is continuous function. A discontinuity is a jump in value. For instance the reciprocal function, fx = x−1  also written fx = 1 x  has a graph that has a shape called a hyperbola. It has a discontinuity at the point x = 0, where its value jumps from −to +, as shown in Figure I.1.3. But the reciprocal function is continuous at all other points. Loosely speaking, if the graph of a continuous function fx has no corners then fx is a differentiable function. If…

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The first derivative of a function at the point x is the slope of the tangent line at x. All linear functions have a constant derivative because the tangent at every point is the line itself. For instance, the linear function fx = 3x + 2 shown in Figure I.1.1 has first derivative 3. But non-linear functions have derivatives whose value depends on the point x at which it is measured. For instance, the quadratic function fx = 2×2 + 4x + 1 has a first derivative that is increasing with x. It has value 0 at the point x…

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For the first time in its 32-year history, the Lancaster Insurance Classic Motor Show is inviting privately owned classics to be part of a Pride of Ownership display at the 13-15 November fixture. The 15 vehicles will includeMark Stewart’s’37Austin Seven van andLuke Greenwood’s ’68 Ford Mustang Rainbow, one of only two survivors. There should be plenty of scope for clubs to interpret the theme – She’s a Beauty – which is one of the centrepieces at the NEC. The organiser also plans to profile the womeninvolved inthe classic scene. If you fancy sitting inEd Daniels’ beautiful Gullwing, you can do…

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Perhaps one of the most hostile environments for many micro-organisms is the atmosphere. Suspended in the air, the tiny microbial propagule may be subjected to desiccation, to the damaging effects of radiant energy from the sun, and the chemical activity of elemental gaseous oxygen (O2) to which it will be intimately exposed. Many micro-organisms, especially Gram-negative bacteria, do indeed die very rapidly when suspended in air and yet, although none is able to grow and multiply in the atmosphere, a significant number of microbes are able to survive and use the turbulence of the air as a means of dispersal.…

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A number of procedures that are performed in dentistry may cause bleeding. Under normal circumstances, these procedures can be performed with little risk; however, patients whose ability to control bleeding is altered by congenital defects in coagulation factors, platelets, or blood vessels may be in grave danger unless the dentist identifies the problem before performing any dental procedure. In most cases, after a patient with a congenital bleeding problem has been identified, steps can be taken to greatly reduce the risks associated with dental procedures. The following disorders are discussed in this chapter: hereditary hemorrhagic telangiectasia (Osler-Weber-Rend syndrome), von Will…

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The foods that we eat are rarely if ever sterile, they carry microbial associations whose composition depends upon which organisms gain access and how they grow, survive and interact in the food over time. The micro-organisms present will originate from the natural micro-flora of the raw material and those organisms introduced in the course of harvesting/slaughter, processing, storage and distribution (see Chapters 2 and The numerical balance between the various types will be determined by the properties of the food, its storage environment, properties of the organisms themselves and the effects of processing. These factors are discussed in more detail…

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