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09-20-2008, 11:43 AM
#211
Blood
Blood is a specialized bodily fluid (technically a tissue). It is composed of blood cells suspended in a liquid called blood plasma. Plasma, which comprises 55% of blood fluid, is mostly water (90% by volume), and contains dissolved proteins, glucose, mineral ions, hormones, carbon dioxide (plasma being the main medium for excretory product transportation), platelets and blood cells themselves. The blood cells present in blood are mainly red blood cells (also called RBCs or erythrocytes) and white blood cells, including leukocytes and platelets (also called thrombocytes).
Blood performs many important functions within the body including:
* Supply of oxygen to tissues (bound to hemoglobin which is carried in red cells)
* Supply of nutrients such as glucose, amino acids and fatty acids (dissolved in the blood or bound to plasma proteins
* Removal of waste such as carbon dioxide, urea and lactic acid
* Immunological functions, including circulation of white cells, and detection of foreign material by antibodies
* Coagulation, which is one part of the body's self-repair mechanism
* Messenger functions, including the transport of hormones and the signaling of tissue damage
* Regulation of body pH (the normal pH of blood is in the range of 7.35 - 7.45)
* Regulation of core body temperature
* Hydraulic functions
Blood accounts for 7% of the human body weight. One microliter of blood contains 4.7 to 6.1 million (male), 4.2 to 5.4 million (female) erythrocytes, 4,000-11,000 leukocytes, 200,000-500,000 thrombocytes.
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09-20-2008, 11:44 AM
#212
Blood Circulation
Blood Circulation
Blood is circulated around the body through blood vessels by the pumping action of the heart. In humans, blood is pumped from the strong left ventricle of the heart through arteries to peripheral tissues and returns to the right atrium of the heart through veins. It then enters the right ventricle and is pumped through the pulmonary artery to the lungs and returns to the left atrium through the pulmonary veins. Blood then enters the left ventricle to be circulated again.
Arterial blood carries oxygen from inhaled air to all of the cells of the body, and venous blood carries carbon dioxide, a waste product of metabolism by cells, to the lungs to be exhaled. However, one exception includes pulmonary arteries which contains the most deoxygenated blood in the body, while the pulmonary veins contain oxygenated blood.
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09-20-2008, 11:49 AM
#213
Blood Donation Facts
Blood Donation Facts
1. Blood is collected only after proper medical examination.
2. All adult males and females in the age range of 18 to 60 years can safely donate blood.
3. Blood donation is completely safe and painless.
4. Out of your total body blood - 5 l -500 ml at a time is taken and that too is restored by your body in 48 hours.
5. It takes only 15 minutes for blood donation. These 15 min will be most precious for someone, because your gift of blood will be a gift of life for him/her.
6. After blood donation, you can perform your routine duties with out any harm.
7. You can safely donate blood once in 3 months.
The donor is also asked about medical history and given a short physical examination to make sure that the donation is not
hazardous to their health. Donors are examined for signs and symptoms of diseases that can be transmitted in a blood transfusion, such as HIV, malaria, and viral hepatitis.
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09-20-2008, 11:50 AM
#214
Blood Donation Facts
The donor's blood type must be determined if the blood will be used for transfusions. The collecting agency usually identifies whether the blood is type A, B, AB, or O and the donor's Rh (D) type and will screen for antibodies to less common antigens. More testing, including a crossmatch, is usually done before a transfusion. Group O is often cited as the "universal donor" but this only refers to red cell transfusions. For plasma transfusions the system is reversed and AB is the universal donor type.
The most common method is collecting the blood from the donor's vein into a container. The collected blood is typically separated into parts, usually red blood cells and plasma, since most recipients need only a specific component for transfusions. The blood is usually stored in a plastic bag that also contains sodium citrate, phosphate, dextrose, and sometimes adenine. This combination keeps the blood from clotting and preserves it during storage.
Donors are usually kept at the donation site for 10-15 minutes after donating since most adverse reactions take place during or immediately after the donation. Blood centers typically provide light refreshments such as tea and biscuits or a lunch allowance to help the donor recover.
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09-20-2008, 11:56 AM
#215
Blood Donation Facts
The collection can be done manually or with automated equipment that only takes specific portions of the blood. Most of the components of blood used for transfusions have a short shelf life (7 days). The limited storage time means that it is difficult to have a stockpile of blood to prepare for a disaster.
In autologous donation, the blood stored will be transfused back to the donor at a later date, usually after surgery.
The World Health Organization recognizes World Blood Donor Day on 14th June each year to promote blood donation. This is the birthday of Karl Landsteiner, the scientist that discovered the ABO blood group system.
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09-20-2008, 12:00 PM
#216
56 Facts About Blood and Blood Donation
56 Facts About Blood and Blood Donation
One for each day between your blood donation!
1. More than 4.5 million patients need blood transfusions each year in the U.S. and Canada.
2. 43,000 pints: amount of donated blood used each day in the U.S. and Canada.
3. Someone needs blood every two seconds.
4. Only 37 percent of the U.S. population is eligible to donate blood – less than 10 percent do annually**.
5. About 1 in 7 people entering a hospital need blood.
6. One pint of blood can save up to three lives.
7. Healthy adults who are at least 17 years old, and at least 110 pounds may donate about a pint of blood—the most common form of donation—every 56 days, or every two months. Females receive 53 percent of blood transfusions; males receive 47 percent.
8. 94 percent of blood donors are registered voters.
9. Four main red blood cell types: A, B, AB and O. Each can be positive or negative for the Rh factor. AB is the universal recipient; O negative is the universal donor of red blood cells.
10. Dr. Karl Landsteiner first identified the major human blood groups – A, B, AB and O – in 1901.
11. One unit of blood can be separated into several components: red blood cells, plasma, platelets and cryoprecipitate.
12. Red blood cells carry oxygen to the body's organs and tissues.
13. Red blood cells live about 120 days in the circulatory system.
14. Platelets promote blood clotting and give those with leukemia and other cancers a chance to live.
15. Plasma is a pale yellow mixture of water, proteins and salts.
16. Plasma, which is 90 percent water, makes up 55 percent of blood volume.
17. Healthy bone marrow makes a constant supply of red cells, plasma and platelets.
18. Blood or plasma that comes from people who have been paid for it cannot be used to human transfusion.
19. Granulocytes, a type of white blood cell, roll along blood vessel walls in search of bacteria to engulf and destroy.
20. White cells are the body's primary defense against infection.
21. Apheresis is a special kind of blood donation that allows a donor to give specific blood components, such as platelets.
22. 42 days: how long most donated red blood cells can be stored.
23. Five days: how long most donated platelets can be stored.
24. One year: how long frozen plasma can be stored.
25. Much of today's medical care depends on a steady supply of blood from healthy donors.
26. 2.7 pints: the average whole blood and red blood cell transfusion.*
27. Children being treated for cancer, premature infants and children having heart surgery need blood and platelets from donors of all types, especially type O.
28. Anemic patients need blood transfusions to increase their red blood cell levels.
29. Cancer, transplant and trauma patients, and patients undergoing open-heart surgery may require platelet transfusions to survive.
30. Sickle cell disease is an inherited disease that affects more than 80,000 people in the United States, 98 percent of whom are of African descent.
31. Many patients with severe sickle cell disease receive blood transfusions every month.
32. A patient could be forced to pass up a lifesaving organ, if compatible blood is not available to support the transplant.
33. Thirteen tests (11 for infectious diseases) are performed on each unit of donated blood.
34. 17 percent of non-donors cite "never thought about it" as the main reason for not giving, while 15 percent say they're too busy.
35. The #1 reason blood donors say they give is because they "want to help others."
36. Shortages of all blood types happen during the summer and winter holidays.
37. Blood centers often run short of types O and B red blood cells.
38. The rarest blood type is the one not on the shelf when it’s needed by a patient.
39. There is no substitute for human blood.
40. If all blood donors gave three times a year, blood shortages would be a rare event (The current average is about two.).
41. If only one more percent of all Americans would give blood, blood shortages would disappear for the foreseeable future.
42. 46.5 gallons: amount of blood you could donate if you begin at age 17 and donate every 56 days until you reach 79 years old.
43. Four easy steps to donate blood: medical history, quick physical, donation and snacks.
44. The actual blood donation usually takes about 10 minutes. The entire process – from the time you sign in to the time you leave – takes about an hour.
45. After donating blood, you replace the fluid in hours and the red blood cells within four weeks. It takes eight weeks to restore the iron lost after donating.
46. You cannot get AIDS or any other infectious disease by donating blood.
47. 10 pints: amount of blood in the body of an average adult.
48. One unit of whole blood is roughly the equivalent of one pint.
49. Blood makes up about 7 percent of your body's weight.
50. A newborn baby has about one cup of blood in his body.
51. Giving blood will not decrease your strength.
52. Any company, community organization, place of worship or individual may contact their local community blood center to host a blood drive.
53. Blood drives hosted by companies, schools, places of worship and civic organizations supply roughly half of all blood donations across the United States.
54. People who donate blood are volunteers and are not paid for their donation.
55. 500,000: the number of Americans who donated blood in the days following the September 11 attacks.
56. Blood donation. It's about an hour of your time. It's About Life.
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09-21-2008, 01:36 PM
#217
Fun Swiss Facts
Thank You Sanil for Sharing the Blood Donation Facts.
Fun Swiss Facts
* Did you know that Switzerland legalized use of marijuana in 2002? (But sales are not legal).
* The Swiss Guard have been famously fierce mercenaries from the 15th to 19th centuries, but now only 100 are left, serving just the Pope & Vatican City.
* Switzerland stayed neutral in both world wars, yet today every fit man serves in the army and stays in the reserves, and every household contains a bomb shelter and gun!.
* In 2002, Switzerland finally joined the United Nations. More recently, the Swiss almost voted away their military.
* Swiss commas are decimal points, and vice versa: €1,50 is one and a half euros, and an American mile contains 5.280 feet. Also, when counting on your fingers, #1 is your thumb!.
* Switzerland has 3 official languages: German=64%, French=20%, and Italian=7%. A fourth language, Romansh (or Romansch), is spoken by only 0.5%. Other languages include: Serbo-Croatian=1.5%, Albanian=1.3%, Portuguese=1.2%, Spanish=1.1%, and English=1% (2000 census).
* An American’s “second floor” of a building is the first floor in Europe.
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10-10-2008, 04:11 AM
#218
Morphing
Morphing is a special effect in motion pictures and animations that changes (or morphs) one image into another through a seamless transition. Most often it is used to depict one person turning into another through some magical or technological means or as part of a fantasy or surreal sequence. Traditionally such a depiction would be achieved through cross-fading techniques on film.
In the early 1990s computer techniques that often produced more convincing results began to be widely used. These involved distorting one image at the same time that it faded into another through marking corresponding points and vectors on the "before" and "after" images used in the morph. For example, one would morph one face into another by marking key points on the first face, such as the contour of the nose or location of an eye, and mark where these same points existed on the second face. The computer would then distort the first face to have the shape of the second face at the same time that it faded the two faces.

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10-14-2008, 03:47 PM
#219
Cannabis (marijuana)
Cannabis, also known as marijuana or marihuana, or ganja is a psychoactive product of the plant Cannabis sativa, or more often, Cannabis sativa subsp. indica. The herbal form of the drug consists of dried mature flowers and subtending leaves of pistillate (female) plants. The resinous form, known as hashish, consists primarily of glandular trichomes collected from the same plant material. The major biologically active chemical compound in cannabis is delta-9-tetrahydrocannabinol, commonly referred to as THC.
Humans have been consuming cannabis since prehistory, although in the 20th century there was a rise in its use for recreational, religious or spiritual, and medicinal purposes. It is estimated that about four percent of the world's adult population use cannabis annually and 0.6 percent daily. Cannabis is the world's most often used illegal drug. The possession, use, or sale of psychoactive cannabis products became illegal in most parts of the world in the early 20th century. Since then, some countries have intensified the enforcement of cannabis prohibition while others have reduced the priority of enforcement.
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10-14-2008, 03:48 PM
#220
Methods of consumption : Cannabis
Methods of consumption
Cannabis is consumed in myriad ways, most of which either involve inhaling smoke from ignited plant or administering orally. Various devices exist for smoking, most common are implements such as bongs, chillums and smoking pipes, joints or blunts. Local methods differ by the preparation of the cannabis plant before use, the parts of the cannabis plant which are used, and the treatment of the smoke before inhalation.
Vaporizer heats herbal cannabis to 185–210 °C, which causes the active ingredients to evaporate into a gas without burning the plant material (the boiling point of THC is 200°C at 0.02 mm Hg pressure, and somewhat higher at standard atmospheric pressure), A lower proportion of toxic chemicals are released than by smoking, although this may vary depending on the design of the vaporizer and the temperature at which it is set.
An e-cigarette has a rechargeable battery and a heating element which vaporizes (in most brands) liquid nicotine from an insertable cartridge. If THC is loaded into the cartridge instead of nicotine, cannabis users may receive the benefits of a vaporizer at lower initial cost.
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