In zootomy and dermatology, skin is an organ of the integumentary system composed of a layer of tissues that protect underlying muscles and organs. As the interface with the surroundings, it plays the most important role in protecting against pathogens. Its other main functions are insulation and temperature regulation, sensation and vitamin D and B synthesis. Skin is composed of the epidermis and the dermis. Below these layers lies the hypodermis(subcutaneous adipose layer), which is not usually classified as a layer of skin. The outermost epidermis is consists of stratified squamous epithelium with an underlying basement membrane. It contains no blood vessels, and is nourished by diffusion from the dermis. The main type of cells which make up the epidermis are keratinocytes, with melanocytes and Langerhans cells also present. The epidermis can be further subdivided into the following strata (beginning with the outermost layer): corneum, lucidum, granulosum, spinosum, basale. Cells are formed through mitosis at the innermost layers. They move up the strata changing shape and composition as they differentiate, inducing expression of new types of keratin genes. They eventually reach the corneum and become sloughed off (desquamation). This process is called keratinization and takes place within about 30 days. This layer of skin is responsible for keeping water in the body and keeping other harmful chemicals and pathogens out. The dermis lies below the epidermis and contains a number of structures including blood vessels, nerves, hair follicles, smooth muscle, glands and lymphatic tissue. It consists of loose connective tissue otherwise called areolar connective tissue - collagen, elastin and reticular fibres are present. Erector muscles, attached between the hair papilla and epidermis, can contract, resulting in the hair fibre pulled upright and consequentially goose bumps. The hypodermis is not part of the skin, and lies below the dermis. Its purpose is to attach the skin to underlying bone and muscle as well as supplying it with blood vessels and nerves. It consists of loose connective tissue and elastin. The main cell types are fibroblasts, macrophages and adipocytes (the hypodermis contains 50% of body fat). Fat serves as padding and insulation for the body. Functions of the skin are disturbed when it is dirty and it becomes more easily damaged. The release of antibacterial compounds decreases. Dirty skin is more prone to develop infections. Cosmetics should be used carefully because these may cause allergic reactions. Each season requires suitable clothing in order to facilitate the evaporation of the sweat. Sunlight, water and air play an important role in keeping the skin healthy.
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Orgasm disorders are a persistent delay or absence of orgasm following a normal sexual excitement phase. The disorder can occur in both women and men. Again, the SSRI antidepressants are frequent culprits -- these can delay the achievement of orgasm or eliminate it entirely. Sexual dysfunction is more common in people who abuse alcohol and drugs. It is also more likely in people suffering from diabetes and degenerative neurological disorders. Ongoing psychological problems, difficulty maintaining relationships or chronic disharmony with the current sexual partner can also interfere with sexual function. A recent study estimates that 30 million men suffer from various degrees of erectile dysfunction. This can range from mild to severe. It is clearly an age-related phenomenon with the prevalence of erectile dysfunction increasing significantly with age. Surprisingly, by the time men reach 40, 5% of them are completely impotent never achieving an erection rigid enough for penetration. Approximately 15% have significant problems achieving or maintaining an erection. The best way for men to begin solving erectile problems is by reading about men's sexual system - anatomy, physiology, diseases, drugs, diagnosis and treatments. Some problems may be solved simply and others may require a visit to your family doctor or a urologist. In either case, we encourage you to become an educated health care consumer, which should help you regardless of the cause or cure for your problem. An erection occurs when the nervous system activates a rapid increase in blood flow. The vascular muscle in the spongy area becomes engorged with blood and the outflow of blood is cut off. An erection can occur as a reflex as we see in spinal cord patients, or can be caused by psychogenic (originating in the mind) stimulation. Numerous sexual stimuli are processed by the brain and transmitted to the penis via the nervous system. Little is known about how to prevent erectile dysfunction. However, avoiding cigarette smoking and maintaining normal blood pressure and cholesterol levels can help because smoking and high cholesterol can affect blood vessels. Men with diabetes should strive to keep blood sugar levels under control. Because certain medications have been associated with erectile dysfunction, ask your doctor about possible side effects before you start using any new prescription.
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Both fear and anxiety send signals through the body that prepare all systems for possible danger. Hormones, such as adrenaline and catecholamine, are released in what is known as the "fight or flight" response. The sudden increase in hormone levels speeds up the heart and increases the amount of blood being pumped. At the same time, the muscles tighten, increasing the individual's ability to fight or flee from danger. The intensity of these physiological responses varies according to the seriousness of the event or thought that sparked the emotion, the strength of the individual's fear or anxiety, and his or her previous experience and genetic makeup. Thousands of scientific studies over the past several years show that high blood pressure, ulcers, migraine headaches, strokes, alcoholism, depression, anger, fatigue, drug addiction and many other medical conditions are often due to the long-term effects of stress. 1. Remember that though your feelings and symptoms are very frightening, they are not dangerous or harmful.
2. Understand that what you are experiencing is an exaggeration of your normal bodily reactions to stress.
3. Do not fight your feelings or try to wish them away. The more you are willing to face them, the less intense they will become.
4. Do not add to your panic by thinking about what "might" happen.
5. Stay in the present. Notice what is really happening to you as opposed to what you think might happen.
6. Label your fear level from zero to 10 and watch it go up and down. Notice that it does not stay at a very high level for more than a few seconds.
7. When the fear begins to trigger "what if" thinking, focus on and carry out a simple and manageable task such as counting backwards from 100 by threes or snapping a rubber band on your wrist.
8. Notice that when you stop adding frightening thoughts to your fear, it begins to fade.
9. When the fear comes, expect and accept it. Wait and give it time to pass without running away from it.
10. Be proud of the progress you make, and think about how good you will feel when you succeed this time. Also, research indicates that other brain parts called the basal ganglia and striatum are involved in obsessive-compulsive disorder. Psychopharmacology, the treatment of psychiatric disorders and emotional distress with medication, has developed over the last fifty years, as our understanding of the workings of the brain has increased in sophistication. When medication is prescribed for mental and emotional illness, the most frequent goal is to restore the chemical balance within the brain, thereby restoring equilibrium to the entire system. Certain drugs function to address certain symptoms, such as when sedatives are prescribed for insomnia. Medications can work to slow disease processes, such as when anti-oxidants are used to treat Alzheimer's. Still other drugs control cravings and curb other problematic behaviors, such as taken to control alcoholism.
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